bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from PTEN Loss Promotes rasHa-Mediated Papillomatogenesis via Dual Up-Regulation of AKT Activity and Cell Cycle Deregulation but Malignant Conversion Proceeds via PTEN-Associated Pathways
Authors: Yao Denggao , Alexander Claire L. , Quinn Jean A. , Porter Michael J. , Wu Hong , Greenhalgh David A.
Published: March 2023

Abstract
PTEN tumor suppressor gene failure in rasHa-activated skin carcinogenesis was investigated by mating exon 5 floxed-PTEN (Δ5PTEN) mice to HK1.ras mice that expressed a RU486-inducible cre recombinase (K14.creP). PTEN inactivation in K14.cre/PTENflx/flx keratinocytes resulted in epidermal hyperplasia/hyperkeratosis and novel 12-O-tetradecanoylphorbol-13-acetate (TPA)–promoted papillomas, whereas HK1.ras/K14.cre/PTENflx/flx cohorts displayed a rapid onset of papillomatogenesis due to a synergism of increased AKT activity and extracellular signal-regulated kinase (ERK) elevation. High 5-bromo-4-deoxyuridine labeling in Δ5PTEN papillomas showed that a second promotion mechanism centered on failures in cell cycle control. Elevated cyclin D1 was associated with both HK1.ras/ERK– and Δ5PTEN-mediated AKT signaling, whereas cyclin E2 overexpression seemed dependent on PTEN loss. Spontaneous HK1.ras/Δ5PTEN malignant conversion was rare, whereas TPA promotion resulted in conversion with high frequency. On comparison with all previous HK1.ras carcinomas, such TPA-induced carcinomas expressed atypical retention of keratin K1 and lack of K13, a unique marker profile exhibited by TPA-induced K14.cre/PTENflx/flx papillomas that also lacked endogenous c-rasHa activation. Moreover, in all PTEN-null tumors, levels of rasHa-associated total ERK protein became reduced, whereas phosphorylated ERK and cyclin D1 were lowered in late-stage papillomas returning to elevated levels, alongside increased cyclin E2 expression, in TPA-derived carcinomas. Thus, during early papillomatogenesis, PTEN loss promotes rasHa initiation via elevation of AKT activity and synergistic failures in cyclin regulation. However, in progression, reduced rasHa-associated ERK protein and activity, increased Δ5PTEN-associated cyclin E2 expression, and unique K1/K13 profiles following TPA treatment suggest that PTEN loss, rather than rasHa activation, gives rise to a population of cells with greater malignant potential. (Cancer Res 2006; 66(3): 1302-12)
Data from PRKAR1A Inactivation Leads to Increased Proliferation and Decreased Apoptosis in Human B Lymphocytes
Authors: Robinson-White Audrey J. , Leitner Wolfgang W. , Aleem Eiman , Kaldis Philipp , Bossis Ioannis , Stratakis Constantine A.
Published: March 2023

Abstract
The multiple neoplasia syndrome Carney complex (CNC) is caused by heterozygote mutations in the gene, which codes for the RIα regulatory subunit (PRKAR1A) of protein kinase A. Inactivation of PRKAR1A and the additional loss of the normal allele lead to tumors in CNC patients and increased cyclic AMP signaling in their cells, but the oncogenetic mechanisms in affected tissues remain unknown. Previous studies suggested that PRKAR1A down-regulation may lead to increased mitogen-activated protein kinase (MAPK) signaling. Here, we show that, in lymphocytes with PRKAR1A-inactivating mutations, there is increased extracellular signal-regulated kinase (ERK) 1/2 and B-raf phosphorylation and MAPK/ERK kinase 1/2 and c-Myc activation, whereas c-Raf-1 is inhibited. These changes are accompanied by increased cell cycle rates and decreased apoptosis that result in an overall net gain in proliferation and survival. In conclusion, inactivation of PRKAR1A leads to widespread changes in molecular pathways that control cell cycle and apoptosis. This is the first study to show that human cells with partially inactivated RIα levels have increased proliferation and survival, suggesting that loss of the normal allele in these cells is not necessary for these changes to occur. (Cancer Res 2006; 66(21): 10603-12)
Data from The Possible Role of EWS-Fli1 in Evasion of Senescence in Ewing Family Tumors
Authors: Matsunobu Tomoya , Tanaka Kazuhiro , Nakamura Tomoyuki , Nakatani Fumihiko , Sakimura Riku , Hanada Masuo , Li Xu , Okada Takamitsu , Oda Yoshinao , Tsuneyoshi Masazumi , Iwamoto Yukihide
Published: March 2023

Abstract
The chromosomal translocation t(11;22) yields the EWS-Fli1 fusion gene and is associated with oncogenesis of Ewing family tumors (EFT). In this study, using the RNA interference method, we show that EWS-Fli1–targeting small interfering RNAs (siRNA) depleted EWS-Fli1 protein and caused growth inhibition in EFT cells with the accumulation of p27 protein and the down-regulation of Skp2 protein in dose-dependent, time-dependent, and sequence-specific manners. Depletion of EWS-Fli1 subacutely elicited a senescence-like phenotype, but not apoptosis, in EFT cells. Furthermore, not only the knockdown of p27, but also the forced expression of Skp2, reduced the expression levels of p27 protein and partially rescued senescence-like phenotype caused by EWS-Fli1–targeting siRNAs. The accumulation of p27 protein in EWS-Fli1–depleted cells inhibited cdk2 kinase activity and was related to the stability of p27 protein, which resulted from a decrease in Skp2 protein. Immunohistochemical analysis of p27 and Skp2 proteins in EFT samples revealed that there was an inverse relationship between the expression profiles of p27 and Skp2 proteins. These findings indicate an important role of EWS-Fli1 in the prevention of senescence, leading to the unlimited growth and oncogenesis of EFT cells through a decrease in the stability of p27 protein due to increased action of Skp2-mediated 26S proteasome degradation. (Cancer Res 2006; 66(2): 803-11)
Data from Genetic Ablation of the Amplified-in-Breast Cancer 1 Inhibits Spontaneous Prostate Cancer Progression in Mice
Authors: Chung Arthur C-K. , Zhou Suoling , Liao Lan , Tien Jean Ching-Yi , Greenberg Norman M. , Xu Jianming
Published: March 2023

Abstract
Although the amplified-in-breast cancer 1 (AIB1; SRC-3, ACTR, or NCoA3) was defined as a coactivator for androgen receptor (AR) by in vitro studies, its role in AR-mediated prostate development and prostate cancer remained unexplored. We report here that AIB1 is expressed in the basal and stromal cells but not in the epithelial cells of the normal mouse prostates. AIB1 deficiency only slightly delayed prostate growth and had no effect on androgen-dependent prostate regeneration, suggesting an unessential role of AIB1 in AR function in the prostate. Surprisingly, when prostate tumorigenesis was induced by the SV40 transgene in transgenic adenocarcinoma of the mouse prostate (TRAMP) mice, AIB1 expression was observed in certain epithelial cells of the prostate intraepithelial neoplasia (PIN) and well-differentiated carcinoma and in almost all cells of the poorly differentiated carcinoma. After AIB1 was genetically inactivated in AIB1−/−/TRAMP mice, the progression of prostate tumorigenesis in most AIB1−/−/TRAMP mice was arrested at the well-differentiated carcinoma stage. Wild-type (WT)/TRAMP mice developed progressive, multifocal, and metastatic prostate tumors and died between 25 and 34 weeks. In contrast, AIB1−/−/TRAMP mice only exhibited PIN and early-stage well-differentiated carcinoma by 39 weeks. AIB1−/−/TRAMP prostates showed much lower cell proliferation than WT/TRAMP prostates. Most AIB1−/−/TRAMP mice could survive more than 35 weeks and died with other types of tumors or unknown reasons. Our results indicate that induction of AIB1 expression in partially transformed epithelial cells is essential for progression of prostate tumorigenesis into poorly differentiated carcinoma. Inhibition of AIB1 expression or function in the prostate epithelium may be a potential strategy to suppress prostate cancer initiation and progression. [Cancer Res 2007;67(12):5965–75]
Data from Characterization of Murine JAK2V617F-Positive Myeloproliferative Disease
Authors: Bumm Thomas G.P. , Elsea Collin , Corbin Amie S. , Loriaux Marc , Sherbenou Daniel , Wood Lisa , Deininger Jutta , Silver Richard T. , Druker Brian J. , Deininger Michael W.N.
Published: March 2023

Abstract
The JAK2V617F mutation is present in almost all patients with polycythemia vera (PV), large proportions of patients with essential thrombocythemia and idiopathic myelofibrosis, and less frequently in atypical myeloproliferative disorders (MPD). We show that transplantation of JAK2V617F-transduced bone marrow into BALB/c mice induces MPD reminiscent of human PV, characterized by erythrocytosis, granulocytosis, extramedullary hematopoiesis, and bone marrow fibrosis, but not thrombocytosis. Fluorescence-activated cell sorting of bone marrow and spleen showed proportional expansion of common myeloid progenitors, granulocyte-monocyte and megakaryocyte-erythrocyte progenitors. Megakaryocyte and late erythroid progenitors were dramatically increased, with only modest expansion of early erythroid progenitors. Erythropoietin (Epo) receptor expression was reduced on early, but normal on late erythroblasts. Serum levels of Epo and granulocyte colony-stimulating factor, but not granulocyte macrophage colony-stimulating factor, were reduced, whereas tumor necrosis factor-α was increased, possibly exerting a negative effect on JAK2V617F-negative hematopoiesis. These data suggest that erythrocytosis and granulocytosis in JAK2V617F mice are the net result of a complex interplay between cell intrinsic and extrinsic factors. There were no thromboembolic events and no animals succumbed to their disease, implicating additional factors in the manifestation of human disease. The disease was not transplantable and prolonged observation showed normalization of blood counts in most JAK2V617F mice, suggesting that the mutation may not confer self-renewal capacity. (Cancer Res 2006; 66(23): 11156-65)
Data from Disruption of the Y-Box Binding Protein-1 Results in Suppression of the Epidermal Growth Factor Receptor and HER-2
Authors: Wu Joyce , Lee Cathy , Yokom Daniel , Jiang Helen , Cheang Maggie C.U. , Yorida Erika , Turbin Dmitry , Berquin Isabelle M. , Mertens Peter R. , Iftner Thomas , Gilks C. Blake , Dunn Sandra E.
Published: March 2023

Abstract
The overexpression of the epidermal growth factor receptor (EGFR) and HER-2 underpin the growth of aggressive breast cancer; still, it is unclear what governs the regulation of these receptors. Our laboratories recently determined that the Y-box binding protein-1 (YB-1), an oncogenic transcription/translation factor, induced breast tumor cell growth in monolayer and in soft agar. Importantly, mutating YB-1 at Ser102, which resides in the DNA-binding domain, prevented growth induction. We reasoned that the underlying cause for growth attenuation by YB-1(Ser102) is through the regulation of EGFR and/or HER-2. The initial link between YB-1 and these receptors was sought by screening primary tumor tissue microarrays. We determined that YB-1 (n = 389 cases) was positively associated with EGFR (P < 0.001, r = 0.213), HER-2 (P = 0.008, r = 0.157), and Ki67 (P < 0.0002, r = 0.219). It was inversely linked to the estrogen receptor (P < 0.001, r = −0.291). Overexpression of YB-1 in a breast cancer cell line increased HER-2 and EGFR. Alternatively, mutation of YB-1 at Ser102 > Ala102 prevented the induction of these receptors and rendered the cells less responsive to EGF. The mutant YB-1 protein was also unable to optimally bind to the EGFR and HER-2 promoters based on chromatin immunoprecipitation. Furthermore, knocking down YB-1 with small interfering RNA suppressed the expression of EGFR and HER-2. This was coupled with a decrease in tumor cell growth. In conclusion, YB-1(Ser102) is a point of molecular vulnerability for maintaining the expression of EGFR and HER-2. Targeting YB-1 or more specifically YB-1(Ser102) are novel approaches to inhibiting the expression of these receptors to ultimately suppress tumor cell growth. (Cancer Res 2006; 66(9): 4872-9)
Data from Epigenetic Silencing of Novel Tumor Suppressors in Malignant Melanoma
Authors: Muthusamy Viswanathan , Duraisamy Sekhar , Bradbury C. Matthew , Hobbs Cara , Curley David P. , Nelson Betsy , Bosenberg Marcus
Published: March 2023

Abstract
Malignant melanoma is a common and frequently lethal disease. Current therapeutic interventions have little effect on survival, emphasizing the need for a better understanding of the genetic, epigenetic, and phenotypic changes in melanoma formation and progression. We identified 17 genes that were not previously known to be silenced by methylation in melanoma using a microarray-based screen following treatment of melanoma cell lines with the DNA methylation inhibitor 5-Aza-2′-deoxycytidine. Eight of these genes have not been previously shown to undergo DNA methylation in any form of cancer. Three of the genes, QPCT, CYP1B1, and LXN, are densely methylated in >95% of uncultured melanoma tumor samples. Reexpression of either of two of the silenced genes, HOXB13 and SYK, resulted in reduced colony formation in vitro and diminished tumor formation in vivo, indicating that these genes function as tumor suppressors in melanoma. (Cancer Res 2006; 66(23): 11187-93)
Data from Tumor-Suppressive Effects of Pannexin 1 in C6 Glioma Cells
Authors: Lai Charles P.K. , Bechberger John F. , Thompson Roger J. , MacVicar Brian A. , Bruzzone Roberto , Naus Christian C.
Published: March 2023

Abstract
Mammalian gap junction proteins, connexins, have long been implicated in tumor suppression. Recently, a novel family of proteins named pannexins has been identified as the mammalian counterpart of the invertebrate gap junction proteins, innexins. To date, pannexin 1 (Panx1) and pannexin 2 (Panx2) mRNAs are reported to be expressed in the brain. Most neoplastic cells, including rat C6 gliomas, exhibit reduced connexin expression, aberrant gap junctional intercellular communication (GJIC), and an increased proliferation rate. When gap junctions are up-regulated by transfecting C6 cells with connexin43, GJIC is restored and the proliferation is reduced. In this study, we examined the tumor-suppressive effects of Panx1 expression in C6 cells. Reverse transcription-PCR analysis revealed that C6 cells do not express any of the pannexin transcripts, whereas its nontumorigenic counterpart, rat primary astrocytes, exhibited mRNAs for all three pannexins. On generation of stable C6 transfectants with tagged Panx1 [myc or enhanced green fluorescent protein (EGFP)], a localization of Panx1 expression to the Golgi apparatus and plasma membrane was observed. In addition, Panx1 transfectants exhibited a flattened morphology, which differs greatly from the spindle-shaped control cells (EGFP only). Moreover, Panx1 expression increased gap junctional coupling as shown by the passage of sulforhodamine 101. Finally, we showed that stable expression of Panx1 in C6 cells significantly reduced cell proliferation in monolayers, cell motility, anchorage-independent growth, and in vivo tumor growth in athymic nude mice. Altogether, we conclude that the loss of pannexin expression may participate in the development of C6 gliomas, whereas restoration of Panx1 plays a tumor-suppressive role. [Cancer Res 2007;67(4):1545–54]
Data from Antitumor Activity of a Small-Molecule Inhibitor of Human Silent Information Regulator 2 Enzymes
Authors: Heltweg Birgit , Gatbonton Tonibelle , Schuler Aaron D. , Posakony Jeff , Li Hongzhe , Goehle Sondra , Kollipara Ramya , DePinho Ronald A. , Gu Yansong , Simon Julian A. , Bedalov Antonio
Published: March 2023

Abstract
SIRT1 and other NAD-dependent deacetylases have been implicated in control of cellular responses to stress and in tumorigenesis through deacetylation of important regulatory proteins, including p53 and the BCL6 oncoprotein. Hereby, we describe the identification of a compound we named cambinol that inhibits NAD-dependent deacetylase activity of human SIRT1 and SIRT2. Consistent with the role of SIRT1 in promoting cell survival during stress, inhibition of SIRT1 activity with cambinol during genotoxic stress leads to hyperacetylation of key stress response proteins and promotes cell cycle arrest. Treatment of BCL6-expressing Burkitt lymphoma cells with cambinol as a single agent induced apoptosis, which was accompanied by hyperacetylation of BCL6 and p53. Because acetylation inactivates BCL6 and has the opposite effect on the function of p53 and other checkpoint pathways, the antitumor activity of cambinol in Burkitt lymphoma cells may be accomplished through a combined effect of BCL6 inactivation and checkpoint activation. Cambinol was well tolerated in mice and inhibited growth of Burkitt lymphoma xenografts. Inhibitors of NAD-dependent deacetylases may constitute novel anticancer agents. (Cancer Res 2006; 66(8): 4368-77)
Data from Transcriptional Cooperation between the Transforming Growth Factor-β and Wnt Pathways in Mammary and Intestinal Tumorigenesis
Authors: Labbé Etienne , Lock Lisa , Letamendia Ainhoa , Gorska Agnieszka E. , Gryfe Robert , Gallinger Steven , Moses Harold L. , Attisano Liliana
Published: March 2023

Abstract
Transforming growth factor-β (TGF-β) and Wnt ligands function in numerous developmental processes, and alterations of both signaling pathways are associated with common pathologic conditions, including cancer. To obtain insight into the extent of interdependence of the two signaling cascades in regulating biological responses, we used an oligonucleotide microarray approach to identify Wnt and TGF-β target genes using normal murine mammary gland epithelial cells as a model. Combination treatment of TGF-β and Wnt revealed a novel transcriptional program that could not have been predicted from single ligand treatments and included a cohort of genes that were cooperatively induced by both pathways. These included both novel and known components or modulators of TGF-β and Wnt pathways, suggesting that mutual feedback is a feature of the coordinated activities of the ligands. The majority of the cooperative targets display increased expression in tumors derived from either Min (many intestinal neoplasia) or mouse mammary tumor virus (MMTV)–Wnt1 mice, two models of Wnt-induced tumors, with nine of these genes (Ankrd1, Ccnd1, Ctgf, Gpc1, Hs6st2, IL11, Inhba, Mmp14, and Robo1) showing increases in both. Reduction of TGF-β signaling by expression of a dominant-negative TGF-β type II receptor in bigenic MMTV-Wnt1/DNIIR mice increased mammary tumor latency and was correlated with a decrease in expression of Gpc1, Inhba, and Robo1, three of the TGF-β/Wnt cooperative targets. Our results indicate that the TGF-β and Wnt/β-catenin pathways are firmly intertwined and generate a unique gene expression pattern that can contribute to tumor progression. [Cancer Res 2007;67(1):75–84]
Data from Oncogenic Serine-Threonine Kinase Receptor-Associated Protein Modulates the Function of Ewing Sarcoma Protein through a Novel Mechanism
Authors: Anumanthan Govindaraj , Halder Sunil K. , Friedman David B. , Datta Pran K.
Published: March 2023

Abstract
Although much is known about the oncogenic functions of chimeric Ewing sarcoma (EWS) fusion proteins that result from chromosomal translocations, the cellular role of the normal EWS protein is not well characterized. We have previously identified a WD domain–containing protein, serine-threonine kinase receptor-associated protein (STRAP), which inhibits transforming growth factor β (TGF-β) signaling through interaction with receptors and Smad7 and promotes growth and enhances tumorigenicity. Here, we report the interaction between STRAP and EWS using matrix-assisted laser desorption/ionization, time-of-flight and tandem mass spectrometry. Although STRAP is localized in both cytoplasm and nucleus, nuclear STRAP colocalizes and associates specifically with EWS in the nucleus through its NH2 and COOH termini. We have found that normal EWS protein is up-regulated in human cancers, which correlates with the up-regulation of STRAP in 71% of colorectal cancers and 54% of lung cancers, suggesting a cooperative role of these two proteins in human cancers. TGF-β has no effect on STRAP and EWS interaction. However, EWS, like STRAP, attenuates TGF-β-dependent transcription. STRAP inhibits EWS-dependent p300-mediated transactivation of EWS target genes, such as ApoCIII and c-fos, in a TGF-β-independent manner. Interestingly, we have shown that STRAP blocks the interaction between EWS and p300, whereas the complex formation between STRAP and EWS is not affected by p300. These results suggest that STRAP inhibits the transactivation function of EWS by displacing p300 from the functional transcriptional complex. Thus, this study provides a novel TGF-β-independent function of STRAP and describes a mechanism by which STRAP regulates the function of oncogenic EWS protein. (Cancer Res 2006; 66(22): 10824-32)
Data from Modeling Breast Cancer–Associated c-Src and EGFR Overexpression in Human MECs: c-Src and EGFR Cooperatively Promote Aberrant Three-dimensional Acinar Structure and Invasive Behavior
Authors: Dimri Manjari , Naramura Mayumi , Duan Lei , Chen Jing , Ortega-Cava Cesar , Chen Gengsheng , Goswami Rasna , Fernandes Norvin , Gao Qingshen , Dimri Goberdhan P. , Band Vimla , Band Hamid
Published: March 2023

Abstract
Epidermal growth factor receptor (EGFR), a member of the ErbB family of receptor tyrosine kinases, is overexpressed in as many as 60% cases of breast and other cancers. EGFR overexpression is a characteristic of highly aggressive molecular subtypes of breast cancer with basal-like and BRCA1 mutant phenotypes distinct from ErbB2-overexpressing breast cancers. Yet, EGFR is substantially weaker compared with ErbB2 in promoting the oncogenic transformation of nontumorigenic human mammary epithelial cells (human MEC), suggesting a role for cooperating oncogenes. Here, we have modeled the co-overexpression of EGFR and a biologically and clinically relevant potential modifier c-Src in two distinct immortal but nontumorigenic human MECs. Using a combination of morphologic analysis and confocal imaging of polarity markers in three-dimensional Matrigel culture together with functional analyses of early oncogenic traits, we show for the first time that EGFR and c-Src co-overexpression but not EGFR or c-Src overexpression alone unleashes an oncogenic signaling program that leads to hyperproliferation and loss of polarity in three-dimensional acinar cultures, marked enhancement of migratory and invasive behavior, and anchorage-independent growth. Our results establish that EGFR overexpression in an appropriate context (modeled here using c-Src overexpression) can initiate oncogenic transformation of nontumorigenic human MECs and provide a suitable in vitro model to interrogate human breast cancer–relevant oncogenic signaling pathways initiated by overexpressed EGFR and to identify modifiers of EGFR-mediated breast oncogenesis. [Cancer Res 2007;67(9):4164–72]
Data from Diagnostic Markers of Ovarian Cancer by High-Throughput Antigen Cloning and Detection on Arrays
Authors: Chatterjee Madhumita , Mohapatra Saroj , Ionan Alexei , Bawa Gagandeep , Ali-Fehmi Rouba , Wang Xiaoju , Nowak James , Ye Bin , Nahhas Fatimah A. , Lu Karen , Witkin Steven S. , Fishman David , Munkarah Adnan , Morris Robert , Levin Nancy K. , Shirley Natalie N. , Tromp Gerard , Abrams Judith , Draghici Sorin , Tainsky Michael A.
Published: March 2023

Abstract
A noninvasive screening test would significantly facilitate early detection of epithelial ovarian cancer. This study used a combination of high-throughput selection and array-based serologic detection of many antigens indicative of the presence of cancer, thereby using the immune system as a biosensor. This high-throughput selection involved biopanning of an ovarian cancer phage display library using serum immunoglobulins from an ovarian cancer patient as bait. Protein macroarrays containing 480 of these selected antigen clones revealed 65 clones that interacted with immunoglobulins in sera from 32 ovarian cancer patients but not with sera from 25 healthy women or 14 patients having other benign or malignant gynecologic diseases. Sequence analysis data of these 65 clones revealed 62 different antigens. Among the markers, we identified some known antigens, including RCAS1, signal recognition protein-19, AHNAK-related sequence, nuclear autoantogenic sperm protein, Nijmegen breakage syndrome 1 (Nibrin), ribosomal protein L4, Homo sapiens KIAA0419 gene product, eukaryotic initiation factor 5A, and casein kinase II, as well as many previously uncharacterized antigenic gene products. Using these 65 antigens on protein microarrays, we trained neural networks on two-color fluorescent detection of serum IgG binding and found an average sensitivity and specificity of 55% and 98%, respectively. In addition, the top 6 of the most specific clones resulted in an average sensitivity and specificity of 32% and 94%, respectively. This global approach to antigenic profiling, epitomics, has applications to cancer and autoimmune diseases for diagnostic and therapeutic studies. Further work with larger panels of antigens should provide a comprehensive set of markers with sufficient sensitivity and specificity suitable for clinical testing in high-risk populations. (Cancer Res 2006; 66(2): 1181-90)
Data from A Gene Expression Signature that Can Predict Green Tea Exposure and Chemopreventive Efficacy of Lung Cancer in Mice
Authors: Lu Yan , Yao Ruisheng , Yan Ying , Wang Yian , Hara Yukihiko , Lubet Ronald A. , You Ming
Published: March 2023

Abstract
Green tea has been shown to be a potent chemopreventive agent against lung tumorigenesis in animal models. Previously, we found that treatment of A/J mice with either green tea (0.6% in water) or a defined green tea catechin extract (polyphenon E; 2.0 g/kg in diet) inhibited lung tumor tumorigenesis. Here, we described expression profiling of lung tissues derived from these studies to determine the gene expression signature that can predict the exposure and efficacy of green tea in mice. We first profiled global gene expressions in normal lungs versus lung tumors to determine genes which might be associated with the tumorigenic process (TUM genes). Gene expression in control tumors and green tea–treated tumors (either green tea or polyphenon E) were compared to determine those TUM genes whose expression levels in green tea–treated tumors returned to levels seen in normal lungs. We established a 17-gene expression profile specific for exposure to effective doses of either green tea or polyphenon E. This gene expression signature was altered both in normal lungs and lung adenomas when mice were exposed to green tea or polyphenon E. These experiments identified patterns of gene expressions that both offer clues for green tea's potential mechanisms of action and provide a molecular signature specific for green tea exposure. (Cancer Res 2006; 66(4): 1956-63)
Data from Haplotype Analysis of the HSD17B1 Gene and Risk of Breast Cancer: A Comprehensive Approach to Multicenter Analyses of Prospective Cohort Studies
Authors: Feigelson Heather Spencer , Cox David G. , Cann Howard M. , Wacholder Sholom , Kaaks Rudolf , Henderson Brian E. , Albanes Demetrius , Altshuler David , Berglund Goran , Berrino Franco , Bingham Sheila , Buring Julie E. , Burtt Noel P. , Calle Eugenia E. , Chanock Stephen J. , Clavel-Chapelon Francoise , Colditz Graham , Diver W. Ryan , Freedman Matthew L. , Haiman Christopher A. , Hankinson Susan E. , Hayes Richard B. , Hirschhorn Joel N. , Hunter David , Kolonel Laurence N. , Kraft Peter , LeMarchand Loic , Linseisen Jakob , Modi William , Navarro Carmen , Peeters Petra H. , Pike Malcolm C. , Riboli Elio , Setiawan V. Wendy , Stram Daniel O. , Thomas Gilles , Thun Michael J. , Tjonneland Anne , Trichopoulos Dimitrios
Published: March 2023

Abstract
The 17β-hydroxysteroid dehydrogenase 1 gene (HSD17B1) encodes 17HSD1, which catalyzes the final step of estradiol biosynthesis. Despite the important role of HSD17B1 in hormone metabolism, few epidemiologic studies of HSD17B1 and breast cancer have been conducted. This study includes 5,370 breast cancer cases and 7,480 matched controls from five large cohorts in the Breast and Prostate Cancer Cohort Consortium. We characterized variation in HSD17B1 by resequencing and dense genotyping a multiethnic sample and identified haplotype-tagging single nucleotide polymorphisms (htSNP) that capture common variation within a 33.3-kb region around HSD17B1. Four htSNPs, including the previously studied SNP rs605059 (S312G), were genotyped to tag five common haplotypes in all cases and controls. Conditional logistic regression was used to estimate odds ratios (OR) for disease. We found no evidence of association between common HSD17B1 haplotypes or htSNPs and overall risk of breast cancer. The OR for each haplotype relative to the most common haplotype ranged from 0.98 to 1.07 (omnibus test for association: X2 = 3.77, P = 0.58, 5 degrees of freedom). When cases were subdivided by estrogen receptor (ER) status, two common haplotypes were associated with ER-negative tumors (test for trend, Ps = 0.0009 and 0.0076; n = 353 cases). HSD17B1 variants that are common in Caucasians are not associated with overall risk of breast cancer; however, there was an association among the subset of ER-negative tumors. Although the probability that these ER-negative findings are false-positive results is high, these findings were consistent across each cohort examined and warrant further study. (Cancer Res 2006; 66(4): 2468-75)
Data from Par-4-Dependent Apoptosis by the Dietary Compound Withaferin A in Prostate Cancer Cells
Authors: Srinivasan Sowmyalakshmi , Ranga Rama S. , Burikhanov Ravshan , Han Seong-Su , Chendil Damodaran
Published: March 2023

Abstract
Deletion or mutation of the androgen receptor (AR) renders prostate tumors refractory to apoptosis by androgen ablation, the mainstay of prostate cancer therapy. To identify novel therapeutics that can induce apoptosis regardless of the AR status of prostate cancer cells, we screened dietary herbal compounds using a reporter assay for the prostate apoptosis response-4 (Par-4) gene, which induces p53- and PTEN-independent and cancer-selective apoptosis. One of the compounds, withaferin A (WA), a major constituent of the dietary compound Withania somnifera, induced Par-4-dependent apoptosis in androgen-refractory prostate cancer cells and regression of PC-3 xenografts in nude mice. Interestingly, restoration of wild-type AR in PC-3 (AR negative) cells abrogated both Par-4 induction and apoptosis by WA. Individually, WA and anti-androgens induced neither Par-4 nor apoptosis in androgen-responsive prostate cancer cells, yet in combination, WA and anti-androgen synergistically induced Par-4 and apoptosis in androgen-responsive prostate cancer cells. Thus, when judiciously combined with anti-androgens, WA inhibits survival of both androgen-responsive and androgen-refractory prostate cancer cells by a Par-4-dependent mechanism. As Par-4 up-regulation induces apoptosis in most tumor cells, our findings can be extended to high-throughput screens to identify synergistic combinations for both therapy-sensitive and therapy-resistant cancers. [Cancer Res 2007;67(1):246–53]
Data from Differential Gene Expression Analysis Reveals Generation of an Autocrine Loop by a Mutant Epidermal Growth Factor Receptor in Glioma Cells
Authors: Ramnarain Deepti B. , Park Seongmi , Lee Diana Y. , Hatanpaa Kimmo J. , Scoggin Shane O. , Otu Hasan , Libermann Towia A. , Raisanen Jack M. , Ashfaq Raheela , Wong Eric T. , Wu Julian , Elliott Robert , Habib Amyn A.
Published: March 2023

Abstract
The epidermal growth factor receptor (EGFR) gene is commonly amplified and rearranged in glioblastoma multiforme leading to overexpression of wild-type and mutant EGFRs. Expression of wild-type EGFR ligands, such as transforming growth factor-α (TGF-α) or heparin-binding EGF (HB-EGF), is also often increased in gliomas resulting in an autocrine loop that contributes to the growth autonomy of glioma cells. Glioblastoma multiformes express a characteristic EGFR mutant (EGFRvIII, de 2-7) that does not bind ligand, signals constitutively, and is more tumorigenic than the wild-type receptor. However, the downstream signals that mediate this increased tumorigenicity are not well understood. We hypothesized that signals induced specifically by EGFRvIII and not the wild-type receptor are more likely to mediate its increased tumorigenic activity and examined the gene expression profiles resulting from inducible expression of comparable levels of either wild-type EGFR or EGFRvIII in a U251-MG glioma cell line. Expression of EGFRvIII resulted in specific up-regulation of a small group of genes. Remarkably, all these genes, which include TGFA, HB-EGF, EPHA2, IL8, MAP4K4, FOSL1, EMP1, and DUSP6, influence signaling pathways known to play a key role in oncogenesis and function in interconnected networks. Increased expression of EGFRvIII-induced genes was validated by real-time PCR. The mutant receptor does not bind ligand, and EGFRvIII-induced expression of TGF-α and HB-EGF suggests that EGFRvIII plays a role in generating an autocrine loop using the wild-type EGFR in glioma. It also raises the possibility that EGFRvIII may signal, at least in part, through the wild-type receptor. Indeed, we show that inhibiting the activity of HB-EGF, a potent mitogen, with neutralizing antibodies reduces cell proliferation induced by expression of EGFRvIII. This suggests that the EGFRvIII-HB-EGF-wild-type EGFR autocrine loop plays an important role in signal transduction by EGFRvIII in glioma cells. We also show by immunohistochemistry that HB-EGF expression correlates with the presence of EGFRvIII in glioblastoma multiforme. Thus, our study provides a new insight into oncogenic signaling by EGFRvIII and improves our understanding of how autocrine loops are generated in glioma. (Cancer Res 2006; 66(2): 867-74)
Data from Human Bone Marrow Activates the Akt Pathway in Metastatic Prostate Cells through Transactivation of the α-Platelet–Derived Growth Factor Receptor
Authors: Dolloff Nathan G. , Russell Mike R. , Loizos Nick , Fatatis Alessandro
Published: March 2023

Abstract
The factors regulating the bone tropism of disseminated prostate cancer cells are still vaguely defined. We report that prostate cancer cells that metastasize to the skeleton respond to human bone marrow with a robust stimulation of the phosphatidylinositol 3-kinase/Akt pathway, whereas prostate cells that lack bone-metastatic potential respond negligibly. The majority of this Akt activation is dependent on α-platelet–derived growth factor receptor (α-PDGFR) signaling, which was shown using the small-molecule inhibitor of PDGFR signaling AG1296. Low concentrations of PDGF-AA and PDGF-BB found in bone marrow aspirates, which were detected by ELISA, do not account for the high levels of α-PDGFR signaling. Additionally, neutralizing PDGF binding using a α-PDGFR–specific antibody (IMC-3G3) failed to produce a significant inhibition of bone marrow–induced Akt activation. However, the inhibitory effect of IMC-3G3 rivaled that of AG1296 when incubation was done under conditions that stimulated α-PDGFR internalization. We conclude that α-PDGFR is activated by multiple soluble factors contained within human bone marrow, in addition to its natural ligands, and this transactivation is dependent on receptor localization to the plasma membrane. Therefore, α-PDGFR expression may provide select prostate phenotypes with a growth advantage within the bone microenvironment. [Cancer Res 2007;67(2):555–62]
Data from Demonstration of a Genetic Therapeutic Index for Tumors Expressing Oncogenic BRAF by the Kinase Inhibitor SB-590885
Authors: King Alastair J. , Patrick Denis R. , Batorsky Roberta S. , Ho Maureen L. , Do Hieu T. , Zhang Shu Yun , Kumar Rakesh , Rusnak David W. , Takle Andrew K. , Wilson David M. , Hugger Erin , Wang Lifu , Karreth Florian , Lougheed Julie C. , Lee Jae , Chau David , Stout Thomas J. , May Earl W. , Rominger Cynthia M. , Schaber Michael D. , Luo Lusong , Lakdawala Ami S. , Adams Jerry L. , Contractor Rooja G. , Smalley Keiran S.M. , Herlyn Meenhard , Morrissey Michael M. , Tuveson David A. , Huang Pearl S.
Published: March 2023

Abstract
Oncogenic BRAF alleles are both necessary and sufficient for cellular transformation, suggesting that chemical inhibition of the activated mutant protein kinase may reverse the tumor phenotype. Here, we report the characterization of SB-590885, a novel triarylimidazole that selectively inhibits Raf kinases with more potency towards B-Raf than c-Raf. Crystallographic analysis revealed that SB-590885 stabilizes the oncogenic B-Raf kinase domain in an active configuration, which is distinct from the previously reported mechanism of action of the multi-kinase inhibitor, BAY43-9006. Malignant cells expressing oncogenic B-Raf show selective inhibition of mitogen-activated protein kinase activation, proliferation, transformation, and tumorigenicity when exposed to SB-590885, whereas other cancer cell lines and normal cells display variable sensitivities or resistance to similar treatment. These studies support the validation of oncogenic B-Raf as a target for cancer therapy and provide the first evidence of a correlation between the expression of oncogenic BRAF alleles and a positive response to a selective B-Raf inhibitor. (Cancer Res 2006; 66(23): 11100-5)
Data from Pten Deficiency Activates Distinct Downstream Signaling Pathways in a Tissue-Specific Manner
Authors: Yoo Lina I. , Liu David W. , Vu Sandrine Le , Bronson Roderick T. , Wu Hong , Yuan Junying
Published: March 2023

Abstract
PTEN deficiency predisposes to a subset of human cancers, but the mechanism that underlies such selectivity is unknown. We have generated a mouse line that conditionally deletes Pten in urogenital epithelium. These mice develop carcinomas at high frequency in the prostate but at relatively low frequency in the bladder, despite early and complete penetrance of hyperplasia in both organs. Cell proliferation is initially high in the bladder of newborn Pten-deficient mice but within days is inhibited by p21 induction. In contrast, proliferation remains elevated in Pten-deficient prostate, where p21 is never induced, suggesting that p21 induction is a bladder-specific compensatory mechanism to inhibit proliferation caused by Pten deletion. Furthermore, the AKT/mammalian target of rapamycin growth pathway, which is highly activated in Pten-deficient prostate, is not activated in bladder epithelium. Our results reveal alternative downstream signaling pathways activated by Pten deficiency that lead to tissue-specific susceptibilities to tumorigenesis. (Cancer Res 2006; 66(4): 1929-39)
Data from Diverse Gene Expression and DNA Methylation Profiles Correlate with Differential Adaptation of Breast Cancer Cells to the Antiestrogens Tamoxifen and Fulvestrant
Authors: Fan Meiyun , Yan Pearlly S. , Hartman-Frey Cori , Chen Lei , Paik Henry , Oyer Samuel L. , Salisbury Jonathan D. , Cheng Alfred S.L. , Li Lang , Abbosh Phillip H. , Huang Tim H-M. , Nephew Kenneth P.
Published: March 2023

Abstract
The development of targeted therapies for antiestrogen-resistant breast cancer requires a detailed understanding of its molecular characteristics. To further elucidate the molecular events underlying acquired resistance to the antiestrogens tamoxifen and fulvestrant, we established drug-resistant sublines from a single colony of hormone-dependent breast cancer MCF7 cells. These model systems allowed us to examine the cellular and molecular changes induced by antiestrogens in the context of a uniform clonal background. Global changes in both basal and estrogen-induced gene expression profiles were determined in hormone-sensitive and hormonal-resistant sublines using Affymetrix Human Genome U133 Plus 2.0 Arrays. Changes in DNA methylation were assessed by differential methylation hybridization, a high-throughput promoter CpG island microarray analysis. By comparative studies, we found distinct gene expression and promoter DNA methylation profiles associated with acquired resistance to fulvestrant versus tamoxifen. Fulvestrant resistance was characterized by pronounced up-regulation of multiple growth-stimulatory pathways, resulting in estrogen receptor α (ERα)–independent, autocrine-regulated proliferation. Conversely, acquired resistance to tamoxifen correlated with maintenance of the ERα-positive phenotype, although receptor-mediated gene regulation was altered. Activation of growth-promoting genes, due to promoter hypomethylation, was more frequently observed in antiestrogen-resistant cells compared with gene inactivation by promoter hypermethylation, revealing an unexpected insight into the molecular changes associated with endocrine resistance. In summary, this study provides an in-depth understanding of the molecular changes specific to acquired resistance to clinically important antiestrogens. Such knowledge of resistance-associated mechanisms could allow for identification of therapy targets and strategies for resensitization to these well-established antihormonal agents. (Cancer Res 2006; 66(24): 11954–66)
Data from Decreased NKX3.1 Protein Expression in Focal Prostatic Atrophy, Prostatic Intraepithelial Neoplasia, and Adenocarcinoma: Association with Gleason Score and Chromosome 8p Deletion
Authors: Bethel Carlise R. , Faith Dennis , Li Xiang , Guan Bin , Hicks Jessica L. , Lan Fusheng , Jenkins Robert B. , Bieberich Charles J. , De Marzo Angelo M.
Published: March 2023

Abstract
NKX3.1 is a homeobox gene located at chromosome 8p21.2, and one copy is frequently deleted in prostate carcinoma. Prior studies of NKX3.1 mRNA and protein in human prostate cancer and prostatic intraepithelial neoplasia (PIN) have been conflicting, and expression in focal prostate atrophy lesions has not been investigated. Immunohistochemical staining for NKX3.1 on human tissue microarrays was decreased in most focal atrophy and PIN lesions. In carcinoma, staining was inversely correlated with Gleason grade. Fluorescence in situ hybridization showed that no cases of atrophy had loss or gain of 8p, 8 centromere, or 8q24 (C-MYC) and only 12% of high-grade PIN lesions harbored loss of 8p. By contrast, NKX3.1 staining in carcinoma was correlated with 8p loss and allelic loss was inversely related to Gleason pattern. Quantitative reverse transcription-PCR for NKX3.1 mRNA using microdissected atrophy revealed a concordance with protein in five of seven cases. In carcinoma, mRNA levels were decreased in 6 of 12 cases but mRNA levels correlated with protein levels in only 4 of 12 cases, indicating translational or post-translational control. In summary, NKX3.1 protein is reduced in focal atrophy and PIN but is not related to 8p allelic loss in these lesions. Therefore, whereas genetic disruption of NKX3.1 in mice leads to PIN, nongenetic mechanisms reduce NKX3.1 protein levels early in human prostate carcinogenesis, which may facilitate both proliferation and DNA damage in atrophic and PIN cells. Monoallelic deletions on chromosome 8p are associated with more advanced invasive and aggressive disease. (Cancer Res 2006; 66(22): 10683-90)
Data from Expression and Regulatory Role of GAIP-Interacting Protein GIPC in Pancreatic Adenocarcinoma
Authors: Muders Michael H. , Dutta Shamit K. , Wang Ling , Lau Julie S. , Bhattacharya Resham , Smyrk Thomas C. , Chari Suresh T. , Datta Kaustubh , Mukhopadhyay Debabrata
Published: March 2023

Abstract
Regulator of G-protein signaling–GAIP-interacting protein COOH terminus (GIPC) is involved in protein trafficking, endocytosis, and receptor clustering and is associated with insulin-like growth factor I receptor (IGF-IR), a receptor important for proliferation and anchorage-independent growth. Here, we described GIPC expression in different human pancreatic adenocarcinoma (PCA) cell lines and we examined the role of GIPC in the regulation of IGF-IR protein levels in PCA. Interestingly, inhibition of GIPC expression by RNA interference led to reduced IGF-IR protein levels and a subsequent decrease in proliferation of PCA cells. We also determined that the PDZ domain of GIPC is essential for the post-translational regulation and the binding of IGF-IR. The importance of GIPC in pancreatic cancer development and progression is supported by tissue microarray data of 300 pancreatic cancer specimens where GIPC is highly expressed in PCA. Taken together, our data suggest that GIPC is a central molecule for the stability of IGF-IR and could be a target for future therapy. (Cancer Res 2006; 66(21): 10264-8)
Data from Frequent Met Oncogene Amplification in a Brca1/Trp53 Mouse Model of Mammary Tumorigenesis
Authors: Smolen Gromoslaw A. , Muir Beth , Mohapatra Gayatry , Barmettler Anne , Kim Woo J. , Rivera Miguel N. , Haserlat Sara M. , Okimoto Ross A. , Kwak Eunice , Dahiya Sonika , Garber Judy E. , Bell Daphne W. , Sgroi Dennis C. , Chin Lynda , Deng Chu-Xia , Haber Daniel A.
Published: March 2023

Abstract
In a screen for gene copy number alterations in mouse mammary tumors initiated by loss of the Brca1 and Trp53 genes, we observed that the majority (11 of 15; 73%) had high-level amplification of wild-type Met, encoding a growth factor receptor implicated in tumor progression. Met amplification was localized to unstable double minute chromosomes and was uniquely found in mouse breast tumors driven by loss of Brca1 and Trp53. Whereas analogous MET amplification was not found in human breast cancers, the identification of a dominant somatic genetic lesion in the Brca1/Trp53 mouse model suggests that recurrent secondary hits may also exist in BRCA1-initiated human breast cancer. (Cancer Res 2006; 66(7): 3452-5)
Data from Up-regulation of GPR48 Induced by Down-regulation of p27Kip1 Enhances Carcinoma Cell Invasiveness and Metastasis
Authors: Gao Yun , Kitagawa Kyoko , Hiramatsu Yoshihiro , Kikuchi Hirotoshi , Isobe Tomoyasu , Shimada Mai , Uchida Chiharu , Hattori Takayuki , Oda Toshiaki , Nakayama Keiko , Nakayama Keiichi I. , Tanaka Tatsuo , Konno Hiroyuki , Kitagawa Masatoshi
Published: March 2023

Abstract
A reduced expression level of the cyclin-dependent kinase inhibitor p27Kip1 is associated with increased tumor malignancy and poor prognosis in individuals with various types of cancer. To investigate the basis for this relation, we applied microarray analysis to screen for genes differentially expressed between p27+/− and parental (p27+/+) HCT116 human colon carcinoma cells. Expression of the gene for G protein–coupled receptor 48 (GPR48) was increased in the p27+/− cells. Forced expression of GPR48 increased both in vitro invasive activity and lung metastasis potency of HCT116 cells. In contrast, depletion of endogenous GPR48 by RNA interference reduced the invasive potential of HeLa and Lewis lung carcinoma cells not only in vitro but also in vivo. Moreover, GPR48 expression was significantly associated with lymph node metastasis and inversely correlated with p27 expression in human colon carcinomas. GPR48 may thus play an important role in invasiveness and metastasis of carcinoma and might therefore represent a potential prognostic marker or therapeutic target. (Cancer Res 2006; 66(24): 11623-31)
Data from Amplification and Overexpression of CTTN (EMS1) Contribute to the Metastasis of Esophageal Squamous Cell Carcinoma by Promoting Cell Migration and Anoikis Resistance
Authors: Luo Man-Li , Shen Xiao-Ming , Zhang Yu , Wei Fang , Xu Xin , Cai Yan , Zhang Xun , Sun Yun-Tian , Zhan Qi-Min , Wu Min , Wang Ming-Rong
Published: March 2023

Abstract
Gain of chromosome 11q13 is a common event in esophageal squamous cell carcinoma (ESCC). The cortactin gene (CTTN, also EMS1), located at 11q13, plays a pivotal role in coupling membrane dynamics to cortical actin assembly. This gene has been implicated in the motility of several types of cells. In the present study, we found that the amplification and overexpression of the CTTN gene was associated with lymph node metastasis in ESCC. Functional analysis by small interfering RNA–mediated silencing of CTTN revealed that in addition to the effect on cell migration, CTTN influenced cell invasiveness by anoikis resistance. In vivo assay showed that inhibition of CTTN expression also decreased tumor growth and lung metastasis of ESCC cells. At the molecular level, we showed for the first time that the protective role of CTTN in anoikis resistance was correlated with the activation of the phosphatidylinositol 3-kinase/Akt pathway. Overall, the data suggest that CTTN is an oncogene in the 11q13 amplicon and exerts functions on tumor metastasis in ESCC. (Cancer Res 2006; 66(24): 11690-9)