bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Regulatory T Cell–Resistant CD8+ T Cells Induced by Glucocorticoid-Induced Tumor Necrosis Factor Receptor Signaling
Authors: Nishikawa Hiroyoshi , Kato Takuma , Hirayama Michiko , Orito Yuki , Sato Eiichi , Harada Naozumi , Gnjatic Sacha , Old Lloyd J. , Shiku Hiroshi
Published: March 2023

Abstract
We previously found that a Salmonella typhimurium vector engineered to secrete soluble tumor antigen induces CD4+ T cells resistant to CD4+CD25+ regulatory T cells (Treg) and that glucocorticoid-induced tumor necrosis factor receptor family-related gene (GITR) signal is involved in the development of this resistance. In this study, we address the potential of incorporating GITR ligand (GITRL) as a way to augment the immunogenicity of cancer vaccines. BALB/c mice were immunized by gene gun with plasmids encoding the mutated extracellular signal-regulated kinase 2 (mERK) with or without plasmids encoding mouse GITRL. Coadministration with GITRL during primary and secondary immunization enhanced the induction of mERK-specific CD8+ T cells. Antibody depletion and minigene analysis suggested that GITRL directly activated CTL epitope-specific CD8+ T cells independently of CD4+ T cells. Immunization with plasmids encoding a CTL epitope and GITRL resulted in strong tumor inhibition in a CD8+ T cell–dependent manner. Furthermore, CTL epitope-specific CD8+ T cells induced by immunization with plasmids encoding CTL epitope coadministered with GITRL were refractory to suppression by CD4+CD25+ Tregs compared with CD8+ T cells induced without GITR signaling. We propose that coadministration of GITR signaling agents with tumor antigens constitutes a promising novel strategy for cancer vaccine development. [Cancer Res 2008;68(14):5948–54]
Data from Epithelial-Mesenchymal Transition in Breast Cancer Relates to the Basal-like Phenotype
Authors: Sarrió David , Rodriguez-Pinilla Socorro María , Hardisson David , Cano Amparo , Moreno-Bueno Gema , Palacios José
Published: March 2023

Abstract
Epithelial-mesenchymal transition (EMT) is defined by the loss of epithelial characteristics and the acquisition of a mesenchymal phenotype. In carcinoma cells, EMT can be associated with increased aggressiveness, and invasive and metastatic potential. To assess the occurrence of EMT in human breast tumors, we conducted a tissue microarray–based immunohistochemical study in 479 invasive breast carcinomas and 12 carcinosarcomas using 28 different markers. Unsupervised hierarchical clustering of the tumors and statistical analysis showed that up-regulation of EMT markers (vimentin, smooth-muscle-actin, N-cadherin, and cadherin-11) and overexpression of proteins involved in extracellular matrix remodeling and invasion (SPARC, laminin, and fascin), together with reduction of characteristic epithelial markers (E-cadherin and cytokeratins), preferentially occur in breast tumors with the “basal-like phenotype.” Moreover, most breast carcinosarcomas also had a basal-like phenotype and showed expression of mesenchymal markers in their sarcomatous and epithelial components. To assess whether basal-like cells have intrinsic phenotypic plasticity for mesenchymal transition, we performed in vitro studies with the MCF10A cell line. In response to low cell density, MCF10A cells suffer spontaneous morphologic and phenotypic EMT-like changes, including cytoskeleton reorganization, vimentin and Slug up-regulation, cadherin switching, and diffuse cytosolic relocalization of the catenins. Moreover, these phenotypic changes are associated with modifications in the global genetic differentiation program characteristic of the EMT process. In summary, our data indicate that in breast tumors, EMT likely occurs within a specific genetic context, the basal phenotype, and suggests that this proclivity to mesenchymal transition may be related to the high aggressiveness and the characteristic metastatic spread of these tumors. [Cancer Res 2008;68(4):989–97]
Data from Overcoming Glutathione S-Transferase P1–Related Cisplatin Resistance in Osteosarcoma
Authors: Pasello Michela , Michelacci Francesca , Scionti Isabella , Hattinger Claudia Maria , Zuntini Monia , Caccuri Anna Maria , Scotlandi Katia , Picci Piero , Serra Massimo
Published: March 2023

Abstract
Cisplatin (cis-diamminedichloroplatinum, CDDP) is one of the most used drugs for osteosarcoma chemotherapy. By using a series of CDDP-resistant variants, which were established from the U-2OS and Saos-2 human osteosarcoma cell lines, we found that CDDP resistance was mainly associated with the increase of both the intracellular level and enzymatic activity of glutathione S-transferase P1 (GSTP1). On the basis of these findings, we evaluated the clinical effect of GSTP1 in a series of 34 high-grade osteosarcoma patients and we found that the increased expression of GSTP1 gene was associated with a significantly higher relapse rate and a worse clinical outcome. These indications prompted us to assess the in vitro effectiveness of 6-(7-nitro-2,1,3-benzoxadiazol-4-ylthio)hexanol (NBDHEX), a promising new anticancer agent that is a highly efficient inhibitor of GSTP1. NBDHEX was tested on a panel of 10 human osteosarcoma cell lines and 20 variants of the U-2OS or Saos-2 cell lines that were resistant to CDDP, doxorubicin, or methotrexate. NBDHEX proved to be very active on the vast majority of these cell lines, including those with higher GSTP1 levels and enzymatic activity. Drug combination studies showed that NBDHEX can be used in association with CDDP and provided useful information about the best modality of their combined administration. In conclusion, our findings show that GSTP1 has a relevant effect for both CDDP resistance and clinical outcome of high-grade osteosarcoma and that targeting GSTP1 with NBDHEX may be considered a promising new therapeutic possibility for osteosarcoma patients who fail to respond to conventional chemotherapy. [Cancer Res 2008;68(16):6661–8]
Data from The Potential Role of Systemic Buffers in Reducing Intratumoral Extracellular pH and Acid-Mediated Invasion
Authors: Silva Ariosto S. , Yunes Jose A. , Gillies Robert J. , Gatenby Robert A.
Published: March 2023

Abstract
A number of studies have shown that the extracellular pH (pHe) in cancers is typically lower than that in normal tissue and that an acidic pHe promotes invasive tumor growth in primary and metastatic cancers. Here, we investigate the hypothesis that increased systemic concentrations of pH buffers reduce intratumoral and peritumoral acidosis and, as a result, inhibit malignant growth. Computer simulations are used to quantify the ability of systemic pH buffers to increase the acidic pHe of tumors in vivo and investigate the chemical specifications of an optimal buffer for such purpose. We show that increased serum concentrations of the sodium bicarbonate (NaHCO3) can be achieved by ingesting amounts that have been used in published clinical trials. Furthermore, we find that consequent reduction of tumor acid concentrations significantly reduces tumor growth and invasion without altering the pH of blood or normal tissues. The simulations also show that the critical parameter governing buffer effectiveness is its pKa. This indicates that NaHCO3, with a pKa of 6.1, is not an ideal intratumoral buffer and that greater intratumoral pHe changes could be obtained using a buffer with a pKa of ∼7. The simulations support the hypothesis that systemic pH buffers can be used to increase the tumor pHe and inhibit tumor invasion. [Cancer Res 2009;69(6):2677–84]
Data from Epidermal Growth Factor Receptor/β-Catenin/T-Cell Factor 4/Matrix Metalloproteinase 1: A New Pathway for Regulating Keratinocyte Invasiveness after UVA Irradiation
Authors: Jean Christine , Blanc Amandine , Prade-Houdellier Naïs , Ysebaert Loïc , Hernandez-Pigeon Hélène , Al Saati Talal , Haure Marie-José , Coluccia Addolorata-Maria-Luce , Charveron Marie , Delabesse Eric , Laurent Guy
Published: March 2023

Abstract
Previous studies have established that UV irradiation results in epidermal growth factor receptor (EGFR) activation in keratinocytes. However, the signaling pathways and cellular effects related to this process remain incompletely elucidated. Herein, we describe for the first time that UVA-mediated EGFR activation results in β-catenin tyrosine phosphorylation at the Y654 residue responsible for the dissociation of E-cadherin/α-catenin/β-catenin complexes. Moreover, UVA induces an EGFR-dependent, but Wnt-independent, β-catenin relocalization from the membrane to the nucleus followed by its association with T-cell factor 4 (TCF4). This newly formed β-catenin/TCF4 complex binds to a specific site on matrix metalloproteinase 1 (MMP1) promoter and governs MMP1 gene and protein expression, as well as cell migration in collagen and gelatin. Altogether, these results suggest that UVA stimulates keratinocyte invasiveness through two coordinated EGFR-dependent processes: loss of cell-to-cell contact due to β-catenin/E-cadherin/α-catenin dissociation and increased cell migration through extracellular matrix component degradation due to β-catenin/TCF4–dependent MMP1 regulation. These events may represent an important step in epidermis repair following UVA injury and their abnormal regulation could contribute to photoaging and photocarcinogenesis. [Cancer Res 2009;69(8):3291–9]
Data from A CreER-Based Random Induction Strategy for Modeling Translocation-Associated Sarcomas in Mice
Authors: Haldar Malay , Hedberg Matthew L. , Hockin Matthew F. , Capecchi Mario R.
Published: March 2023

Abstract
Previously, we reported modeling synovial sarcomas in mice by conditionally expressing the human t(X;18) translocation–derived SYT-SSX2 fusion protein in Myf5-expressing myoblasts. Using a tamoxifen-inducible CreER system in mice, we show here that sporadic expression of SYT-SSX2 across multiple tissue types leads to exclusive formation of synovial sarcoma–like tumors, whereas its widespread expression is lethal. Certain clinical and histologic features of tumors in this new model suggest additional nonmyoblast origin for synovial sarcoma. CreER-based sporadic expression both avoids the severe early developmental phenotypes associated with widespread SYT-SSX2 expression and better models natural pathogenesis of cancers in which transformed cells usually arise within an environment of largely normal cells. Furthermore, this strategy may recapitulate multiple potential cellular origins within a single model system. [Cancer Res 2009;69(8):3657–64]
Data from Diaphanous-Related Formins Are Required for Invadopodia Formation and Invasion of Breast Tumor Cells
Authors: Lizárraga Floria , Poincloux Renaud , Romao Maryse , Montagnac Guillaume , Le Dez Gaëlle , Bonne Isabelle , Rigaill Guillem , Raposo Graça , Chavrier Philippe
Published: March 2023

Abstract
Proteolytic degradation of the extracellular matrix by metastatic tumor cells is initiated by the formation of invadopodia, i.e., actin-driven filopodia-like membrane protrusions endowed with matrix-degradative activity. A signaling cascade involving neural Wiskott-Aldrich syndrome protein and the Arp2/3 actin nucleating complex is involved in actin assembly at invadopodia. Yet, the mechanism of invadopodia formation is poorly understood. Based on their role as actin nucleators in cytoskeletal rearrangements, including filopodia formation, we examined the function of Diaphanous-related formins (DRF) in invadopodia formation and invasion by breast tumor cells. Using small interfering RNA silencing of protein expression in highly invasive MDA-MB-231 breast adenocarcinoma cells, we show that three members of the DRF family (DRF1–DRF3) are required for invadopodia formation and two-dimensional matrix proteolysis. We also report that invasion of a three-dimensional Matrigel matrix involves filopodia-like protrusions enriched for invadopodial proteins, including membrane type 1 matrix metalloproteinase, which depend on DRFs for their formation. These data identify DRFs as critical components of the invasive apparatus of tumor cells in two-dimensional and three-dimensional matrices and suggest that different types of actin nucleators cooperate during the formation of invadopodia. [Cancer Res 2009;69(7):2792–800]
Data from Telomere Dysfunction and DNA-PKcs Deficiency: Characterization and Consequence
Authors: Williams Eli S. , Klingler Rebekah , Ponnaiya Brian , Hardt Tanja , Schrock Evelin , Lees-Miller Susan P. , Meek Katheryn , Ullrich Robert L. , Bailey Susan M.
Published: March 2023

Abstract
The mechanisms by which cells accurately distinguish between DNA double-strand break (DSB) ends and telomeric DNA ends remain poorly defined. Recent investigations have revealed intriguing interactions between DNA repair and telomeres. We were the first to report a requirement for the nonhomologous end-joining (NHEJ) protein DNA-dependent protein kinase (DNA-PK) in the effective end-capping of mammalian telomeres. Here, we report our continued characterization of uncapped (as opposed to shortened) dysfunctional telomeres in cells deficient for the catalytic subunit of DNA-PK (DNA-PKcs) and shed light on their consequence. We present evidence in support of our model that uncapped telomeres in this repair-deficient background are inappropriately detected and processed as DSBs and thus participate not only in spontaneous telomere-telomere fusion but, importantly, also in ionizing radiation–induced telomere-DSB fusion events. We show that phosphorylation of DNA-PKcs itself (Thr-2609 cluster) is a critical event for proper telomere end-processing and that ligase IV (NHEJ) is required for uncapped telomere fusion. We also find uncapped telomeres in cells from the BALB/c mouse, which harbors two single-nucleotide polymorphisms that result in reduced DNA-PKcs abundance and activity, most markedly in mammary tissue, and are both radiosensitive and susceptible to radiogenic mammary cancer. Our results suggest mechanistic links between uncapped/dysfunctional telomeres in DNA-PKcs–deficient backgrounds, radiation-induced instability, and breast cancer. These studies provide the first direct evidence of genetic susceptibility and environmental insult interactions leading to a unique and ongoing form of genomic instability capable of driving carcinogenesis. [Cancer Res 2009;69(5):2100–7]
Data from Breast Cancer Cell Lines Contain Functional Cancer Stem Cells with Metastatic Capacity and a Distinct Molecular Signature
Authors: Charafe-Jauffret Emmanuelle , Ginestier Christophe , Iovino Flora , Wicinski Julien , Cervera Nathalie , Finetti Pascal , Hur Min-Hee , Diebel Mark E. , Monville Florence , Dutcher Julie , Brown Marty , Viens Patrice , Xerri Luc , Bertucci François , Stassi Giorgio , Dontu Gabriela , Birnbaum Daniel , Wicha Max S.
Published: March 2023

Abstract
Tumors may be initiated and maintained by a cellular subcomponent that displays stem cell properties. We have used the expression of aldehyde dehydrogenase as assessed by the ALDEFLUOR assay to isolate and characterize cancer stem cell (CSC) populations in 33 cell lines derived from normal and malignant mammary tissue. Twenty-three of the 33 cell lines contained an ALDEFLUOR-positive population that displayed stem cell properties in vitro and in NOD/SCID xenografts. Gene expression profiling identified a 413-gene CSC profile that included genes known to play a role in stem cell function, as well as genes such as CXCR1/IL-8RA not previously known to play such a role. Recombinant interleukin-8 (IL-8) increased mammosphere formation and the ALDEFLUOR-positive population in breast cancer cell lines. Finally, we show that ALDEFLUOR-positive cells are responsible for mediating metastasis. These studies confirm the hierarchical organization of immortalized cell lines, establish techniques that can facilitate the characterization of regulatory pathways of CSCs, and identify potential stem cell markers and therapeutic targets. [Cancer Res 2009;69(4):1302–13]
Data from Pharmacologic Abrogation of the Mitotic Spindle Checkpoint by an Indolocarbazole Discovered by Cellular Screening Efficiently Kills Cancer Cells
Authors: Stolz Ailine , Vogel Celia , Schneider Verena , Ertych Norman , Kienitz Anne , Yu Hongtao , Bastians Holger
Published: March 2023

Abstract
The mitotic spindle checkpoint represents a signal transduction pathway that prevents the onset of anaphase until all chromosomes are properly aligned on a metaphase plate. Partial inactivation of this checkpoint allows premature separation of sister chromatids and results in aneuploidy, which might contribute to tumorigenesis. Unlike other cell cycle checkpoints, the spindle checkpoint is essential for cell viability, giving rise to the idea that the spindle checkpoint itself might represent a valuable target for anticancer therapy. We used a cell-based screen and identified the indolocarbazole compound Gö6976 as a pharmacologic inhibitor of the spindle checkpoint. Gö6976 potently overrides a spindle checkpoint–mediated mitotic arrest by abrogating the phosphorylation and kinetochore localization of several spindle checkpoint proteins. We identified the Aurora-A and Aurora-B kinases, which have been previously implicated in proper mitotic progression and spindle checkpoint function, as targets for Gö6976. Accordingly, Gö6976 treatment causes severe mitotic abnormalities and chromosome alignment defects, which are not properly detected by the drug-inactivated spindle checkpoint. This results in an aberrant progression of mitosis, leading to apoptosis in various human cancer cell lines, including spindle checkpoint–compromised cancer cells. Thus, our work describes a novel and promising strategy for anticancer treatment that targets the mitotic spindle checkpoint. [Cancer Res 2009;69(9):3874–83]
Data from ADP-Ribosylation Factor 6 Regulates Tumorigenic and Invasive Properties In vivo
Authors: Muralidharan-Chari Vandhana , Hoover Holly , Clancy James , Schweitzer Jill , Suckow Mark A. , Schroeder Valerie , Castellino Francis J. , Schorey Jeffrey S. , D'Souza-Schorey Crislyn
Published: March 2023

Abstract
This study shows that the small GTP-binding protein ADP-ribosylation factor 6 (ARF6) is an important regulator of tumor growth and metastasis. Using spontaneous melanoma tumor growth assays and experimental metastasis assays in nude mice, we show that sustained activation of ARF6 reduces tumor mass growth but significantly enhances the invasive capacity of tumor cells. In contrast, mice injected with tumor cells expressing a dominantly inhibitory ARF6 mutant exhibited a lower incidence and degree of invasion and lung metastasis compared with control animals. Effects on tumor growth correlate with reduced cell proliferation capacity and are linked at least in part to alterations in mitotic progression induced by defective ARF6 cycling. Furthermore, phospho-ERK levels in subcultured cells from ARF6(GTP) and ARF6(GDP) tumor explants correlate with invasive capacity. ARF6-induced extracellular signal-regulated kinase (ERK) signaling leads to Rac1 activation to promote invadopodia formation and cell invasion. These findings document an intricate role for ARF6 and the regulation of ERK activation in orchestrating mechanisms underlying melanoma growth, invasion, and metastases. [Cancer Res 2009;69(6):2201–9]
Data from Targeted Disruption of the S1P2 Sphingosine 1-Phosphate Receptor Gene Leads to Diffuse Large B-Cell Lymphoma Formation
Authors: Cattoretti Giorgio , Mandelbaum Jonathan , Lee Nancy , Chaves Alicia H. , Mahler Ashley M. , Chadburn Amy , Dalla-Favera Riccardo , Pasqualucci Laura , MacLennan A. John
Published: March 2023

Abstract
S1P2 sphingosine 1-phosphate receptor signaling can regulate proliferation, survival, morphology, and migration in many cell types in vitro. Here, we report that S1P2−/− mice develop clonal B-cell lymphomas with age, such that approximately half of the animals display this neoplasm by 1.5 to 2 years of age. Histologic, immunophenotypic, and molecular analyses revealed a uniform tumor phenotype with features of germinal center (GC)–derived diffuse large B-cell lymphoma (DLBCL). Tumor formation was preceded by increases in GC B cells and CD69+ T cells, as well as an increased formation of spontaneous GCs, suggesting that S1P2 loss may promote lymphomagenesis in part by disrupting GC B-cells homeostasis. With the sole exception of rare lung tumors, the effect of S1P2 gene disruption is remarkably restricted to DLBCL. In humans, 28 of 106 (26%) DLBCL samples were found to harbor multiple somatic mutations in the 5′ sequences of the S1P2 gene. Mutations displayed features resembling those generated by the IgV-associated somatic hypermutation mechanism, but were not detected at significant levels in normal GC B cells, indicating a tumor-associated aberrant function. Collectively, our data suggest that S1P2 signaling may play a critical role in suppressing DLBCL formation in vivo. The high incidence of DLBCL in S1P2−/− mice, its onset at old age, and the relative lack of other neoplasms identify these mice as a novel, and potentially valuable, model for this highly prevalent and aggressive human malignancy. [Cancer Res 2009;69(22):8686–92]
Data from A Gonadotropin-Releasing Hormone-II Antagonist Induces Autophagy of Prostate Cancer Cells
Authors: Kim Dong-Ki , Yang Ji Sook , Maiti Kaushik , Hwang Jong-Ik , Kim Kyungjin , Seen Dongseung , Ahn Younghee , Lee Cheolju , Kang Byeong-Cheol , Kwon Hyuk Bang , Cheon Jun , Seong Jae Young
Published: March 2023

Abstract
Gonadotropin-releasing hormone-I (GnRH-I) is known to directly regulate prostate cancer cell proliferation. However, the role of GnRH-II in prostate cancer is unclear. Here, we investigated the effect of the GnRH-II antagonist trptorelix-1 (Trp-1) on growth of PC3 prostate cancer cells. Trp-1 induced growth inhibition of PC3 cells in vitro and inhibited growth of PC3 cells xenografted into nude mice. FITC-N3, an FITC-conjugated Trp-1 analogue, was largely present in the mitochondria of prostate cancer cells, but not in other cells that are not derived from the prostate. Trp-1–induced PC3 growth inhibition was associated with decreased mitochondrial membrane potential and increased levels of mitochondrial and cytosolic reactive oxygen species (ROS). Growth inhibition was partially prevented by cotreating cells with N-acetyl cysteine, an antioxidant. Cytochrome c release and caspase-3 activation were not detected in Trp-1–treated cells. However, Trp-1 induced autophagosome formation, as seen by increased LysoTracker staining and recruitment of microtubule-associated protein 1 light chain 3 to these new lysosomal compartments. Trp-1–induced autophagy was accompanied by decreased AKT phosphorylation and increased c-Jun NH2 terminal kinase phosphorylation, two events known to be linked to autophagy. Taken together, these data suggest that Trp-1 directly induces mitochondrial dysfunction and ROS increase, leading to autophagy of prostate cancer cells. GnRH-II antagonists may hold promise in the treatment of prostate cancer. [Cancer Res 2009;69(3):923–31]
Data from Interleukin 12 Stimulates IFN-γ–Mediated Inhibition of Tumor-Induced Regulatory T-Cell Proliferation and Enhances Tumor Clearance
Authors: Cao Xuefang , Leonard Karen , Collins Lynne I. , Cai Sheng F. , Mayer Joshua C. , Payton Jacqueline E. , Walter Michael J. , Piwnica-Worms David , Schreiber Robert D. , Ley Timothy J.
Published: March 2023

Abstract
To define the factors that modulate regulatory T (Treg) cells in the tumor setting, we cocultured various tumor cells with either purified Treg cells, or with unfractionated splenocytes. We found that Treg expansion occurred only with unfractionated splenocytes, suggesting that accessory cells and/or factors produced by them play an essential role in tumor-induced Treg expansion. We performed gene expression profiling on tumor-associated Treg cells to identify candidate signaling molecules and studied their effects on tumor-induced Treg expansion. We inadvertently discovered that interleukin (IL)-12 treatment blocked Treg expansion in an IL-12 receptor–dependent fashion. Additional studies showed that IL-12 acts by stimulating IFN-γ mediated inhibition of Treg cell proliferation, which may partially account for the antitumor effects of IL-12. Furthermore, IL-12 treatment was found to decrease IL-2 production, which may lead to IFN-γ–independent inhibition of Treg cells, as IL-2 is required for their survival and expansion. Mechanistic studies revealed that IFN-γ signaling directly causes cell cycle arrest in Treg cells. This study shows that an IL-12–IFN-γ axis can suppress tumor-induced Treg proliferation. This mechanism may counteract the ability of Treg cells to promote tumor growth in vivo. [Cancer Res 2009;69(22):8700–9]
Data from Non–Small Cell Lung Cancer Exhibits Transcript Overexpression of Genes Associated with Homologous Recombination and DNA Replication Pathways
Authors: Saviozzi Silvia , Ceppi Paolo , Novello Silvia , Ghio Paolo , Lo Iacono Marco , Borasio Piero , Cambieri Alberto , Volante Marco , Papotti Mauro , Calogero Raffaele A. , Scagliotti Giorgio V.
Published: March 2023

Abstract
Genes involved in DNA repair and replication have been recently investigated as predictive markers of response to chemotherapy in non–small cell lung cancer (NSCLC). However, few data on the expression of these genes in tumor compared with corresponding normal lung are available. The aim of this study was to evaluate differential mRNA levels of 22 DNA repair genes of five different DNA repair pathways: direct, base excision, nucleotide excision (NER), double-strand break (DSBR), and postreplicative repair. In addition, six genes involved in DNA replication (REP) and three telomere maintenance genes were investigated. Total RNAs extracted from fresh-frozen tumors and corresponding normal tissues of 50 consecutive chemo-naïve resected NSCLC patients were analyzed. Transcript levels were quantified by real-time PCR. A significant overexpression was detected in 20 of 30 (67%) genes, mostly belonging to DSBR pathways, whereas others (XPA, XPC, and UBE2N; 10%) were significantly underexpressed. For 7 of 30 (23%) genes, mostly belonging to NER pathway, no significant difference between paired tumor and normal samples was observed. Transcript overexpression of DSBR and REP genes was significantly higher in poorly differentiated carcinomas and DSBR levels were higher in men compared with women. The transcriptional overexpression of four genes (XRCC5, TOP3B, TYMS, and UNG) showed significant correlation with a shorter patients' outcome at the univariate, whereas only stage of disease appeared as an independent factor affecting prognosis, as assessed by multivariate analysis. In conclusion, genes belonging to DNA repair/replication pathways are overexpressed in NSCLC and are associated with a more aggressive phenotype. [Cancer Res 2009;69(8):3390–6]
Data from Introducing Nanochemoprevention as a Novel Approach for Cancer Control: Proof of Principle with Green Tea Polyphenol Epigallocatechin-3-Gallate
Authors: Siddiqui Imtiaz A. , Adhami Vaqar M. , Bharali Dhruba J. , Hafeez Bilal B. , Asim Mohammad , Khwaja Sabih I. , Ahmad Nihal , Cui Huadong , Mousa Shaker A. , Mukhtar Hasan
Published: March 2023

Abstract
Chemoprevention, especially through the use of naturally occurring phytochemicals capable of impeding the process of one or more steps of carcinogenesis process, is a promising approach for cancer management. Despite promising results in preclinical settings, its applicability to humans has met with limited success largely due to inefficient systemic delivery and bioavailability of promising chemopreventive agents. Here, we introduce the concept of nanochemoprevention, which uses nanotechnology for enhancing the outcome of chemoprevention. We encapsulated green tea polyphenol epigallocatechin-3-gallate (EGCG) in polylactic acid–polyethylene glycol nanoparticles and observed that encapsulated EGCG retains its biological effectiveness with over 10-fold dose advantage for exerting its proapoptotic and angiogenesis inhibitory effects, critically important determinants of chemopreventive effects of EGCG in both in vitro and in vivo systems. Thus, this study could serve as a basis for the use of nanoparticle-mediated delivery to enhance bioavailability and limit any unwanted toxicity of chemopreventive agents, such as EGCG. [Cancer Res 2009;69(5):1712–6]
Data from Chemokine Expression in Melanoma Metastases Associated with CD8+ T-Cell Recruitment
Authors: Harlin Helena , Meng Yuru , Peterson Amy C. , Zha Yuanyuan , Tretiakova Maria , Slingluff Craig , McKee Mark , Gajewski Thomas F.
Published: March 2023

Abstract
Despite the frequent detection of circulating tumor antigen–specific T cells, either spontaneously or following active immunization or adoptive transfer, immune-mediated cancer regression occurs only in the minority of patients. One theoretical rate-limiting step is whether effector T cells successfully migrate into metastatic tumor sites. Affymetrix gene expression profiling done on a series of metastatic melanoma biopsies revealed a major segregation of samples based on the presence or absence of T-cell–associated transcripts. The presence of lymphocytes correlated with the expression of defined chemokine genes. A subset of six chemokines (CCL2, CCL3, CCL4, CCL5, CXCL9, and CXCL10) was confirmed by protein array and/or quantitative reverse transcription-PCR to be preferentially expressed in tumors that contained T cells. Corresponding chemokine receptors were found to be up-regulated on human CD8+ effector T cells, and transwell migration assays confirmed the ability of each of these chemokines to promote migration of CD8+ effector cells in vitro. Screening by chemokine protein array identified a subset of melanoma cell lines that produced a similar broad array of chemokines. These melanoma cells more effectively recruited human CD8+ effector T cells when implanted as xenografts in nonobese diabetic/severe combined immunodeficient mice in vivo. Chemokine blockade with specific antibodies inhibited migration of CD8+ T cells. Our results suggest that lack of critical chemokines in a subset of melanoma metastases may limit the migration of activated T cells, which in turn could limit the effectiveness of antitumor immunity. [Cancer Res 2009;69(7):3077–85]
Data from Cyclic AMP Signaling as a Mediator of Vasculogenic Mimicry in Aggressive Human Melanoma Cells In vitro
Authors: Lissitzky Jean-Claude , Parriaux Danielle , Ristorcelli Elodie , Vérine Alain , Lombardo Dominique , Verrando Patrick
Published: March 2023

Abstract
Aggressive melanoma cells can engage in a process termed vasculogenic mimicry (VM) that reflects the ability of tumor cells to express a multipotent, stem cell–like phenotype. Melanoma cell plasticity contributes to the lack of efficient therapeutic strategies targeting metastatic tumors. This study reveals cyclic AMP as a mediator of VM in vitro. In uveal and cutaneous metastatic aggressive human melanoma cells, an increase in cyclic AMP by forskolin, dibutyryl cyclic AMP, or G protein–coupled receptor (GPCR) ligands such as adrenaline and vasoactive intestinal peptide inhibited VM to different extents. Although chemical modulators of protein kinase A (PKA) had no effect, a specific pharmacologic activator of Exchange protein directly activated by cyclic AMP (Epac) impaired VM. Ras-associated protein-1 (Rap1) activation assays revealed that cyclic AMP–elevating agents induce a PKA-independent activation of Epac/Rap1. Pharmacologic inhibition of extracellular signal-regulated kinase 1/2 (ERK1/2) activity abolished VM. Phosphorylation of ERK1/2 was PKA-independently inhibited by forskolin but not inhibited by Epac/Rap1 signaling, PKA modulation, or GPCR ligands. Furthermore, the forskolin also inhibited phosphatidyl inositol-3-kinase (PI3K)-mediated activation of protein kinase Akt, as monitored by Ser473 phosphorylation. The pharmacologic activation of Epac and GPCR ligands slightly stimulated Akt, a likely concomitant process of VM modulation. Collectively, these data show that forskolin strongly inhibits VM through PKA-independent activation of Epac/Rap1, PKA-, and Epac-independent inactivation of ERK1/2 and inhibition of PI3K/Akt. The data also show that VM inhibition by GPCR ligands involves mainly the Epac/Rap1-activated signal. Thus cyclic AMP inhibits VM through multiple signaling pathways. [Cancer Res 2009;69(3):802–9]
Data from PIK3CA Mutations in Colorectal Cancer Are Associated with Clinical Resistance to EGFR-Targeted Monoclonal Antibodies
Authors: Sartore-Bianchi Andrea , Martini Miriam , Molinari Francesca , Veronese Silvio , Nichelatti Michele , Artale Salvatore , Di Nicolantonio Federica , Saletti Piercarlo , De Dosso Sara , Mazzucchelli Luca , Frattini Milo , Siena Salvatore , Bardelli Alberto
Published: March 2023

Abstract
The monoclonal antibodies (moAb) panitumumab and cetuximab target the epidermal growth factor receptor (EGFR) and have proven valuable for the treatment of metastatic colorectal cancer (mCRC). EGFR-mediated signaling involves two main intracellular cascades: on one side KRAS activates BRAF, which in turn triggers the mitogen-activated protein kinases. On the other, membrane localization of the lipid kinase PIK3CA counteracts PTEN and promotes AKT1 phosphorylation, thereby activating a parallel intracellular axis. Constitutive activation of KRAS bypasses the corresponding signaling cascade and, accordingly, patients with mCRC bearing KRAS mutations are clinically resistant to therapy with panitumumab or cetuximab. We hypothesized that mutations activating PIK3CA could also preclude responsiveness to EGFR-targeted moAbs through a similar mechanism. Here, we present the mutational analysis of PIK3CA and KRAS and evaluation of the PTEN protein status in a cohort of 110 patients with mCRC treated with anti-EGFR moAbs. We observed 15 (13.6%) PIK3CA and 32 (29.0%) KRAS mutations. PIK3CA mutations were significantly associated with clinical resistance to panitumumab or cetuximab; none of the mutated patients achieved objective response (P = 0.038). When only KRAS wild-type tumors were analyzed, the statistical correlation was stronger (P = 0.016). Patients with PIK3CA mutations displayed a worse clinical outcome also in terms of progression-free survival (P = 0.035). Our data indicate that PIK3CA mutations can independently hamper the therapeutic response to panitumumab or cetuximab in mCRC. When the molecular status of the PIK3CA/PTEN and KRAS pathways are concomitantly ascertained, up to 70% of mCRC patients unlikely to respond to EGFR moAbs can be identified. [Cancer Res 2009;69(5):1851–7]
Data from Wilms' Tumor 1 Gene Expression in Hepatocellular Carcinoma Promotes Cell Dedifferentiation and Resistance to Chemotherapy
Authors: Perugorria Maria J. , Castillo Josefa , Latasa M. Ujue , Goñi Saioa , Segura Victor , Sangro Bruno , Prieto Jesús , Avila Matías A. , Berasain Carmen
Published: March 2023

Abstract
The Wilms' tumor 1 gene (WT1) encodes a transcription factor involved in cell growth and development. As we previously reported, WT1 expression is hardly detectable in normal hepatic tissue but is induced in liver cirrhosis. Although WT1 has been found to be overexpressed in a number of malignancies, the role of WT1 in hepatocarcinogenesis has not been clarified. We found that WT1 is expressed in several human hepatocellular carcinoma (HCC) cell lines, including PLC/PRF/5 and HepG2, and in HCC tumor tissue in 42% of patients. WT1 small interfering RNAs did not affect proliferation rate of HCC cells but abrogated their resistance to anoikis. Transcriptome analysis of PLC/PRF/5 cells after WT1 knockdown showed up-regulation of 251 genes and down-regulation of 321. Ninety percent of the former corresponded to metabolic genes, mostly those characterizing the mature hepatocyte phenotype. On the contrary, genes that decreased upon WT1 inhibition were mainly related to defense against apoptosis, cell cycle, and tumor progression. In agreement with these findings, WT1 expression increased the resistance of liver tumor cells to doxorubicin, a compound used to treat HCC. Interestingly, doxorubicin strongly enhanced WT1 expression in both HCC cells and normal human hepatocytes. Among different chemotherapeutics, induction of WT1 transcription was restricted to topoisomerase 2 inhibitors. When WT1 expression was prohibited, doxorubicin caused a marked increase in caspase-3 activation. In conclusion, WT1 is expressed in a substantial proportion of HCC contributing to tumor progression and resistance to chemotherapy, suggesting that WT1 may be an important target for HCC treatment. [Cancer Res 2009;69(4):1358–67]
Data from Coordinated Expression of Stathmin Family Members by Far Upstream Sequence Element-Binding Protein-1 Increases Motility in Non–Small Cell Lung Cancer
Authors: Singer Stephan , Malz Mona , Herpel Esther , Warth Arne , Bissinger Michaela , Keith Martina , Muley Thomas , Meister Michael , Hoffmann Hans , Penzel Roland , Gdynia Georg , Ehemann Volker , Schnabel Philipp Albert , Kuner Ruprecht , Huber Peter , Schirmacher Peter , Breuhahn Kai
Published: March 2023

Abstract
Dynamic instability of the microtubule network modulates processes such as cell division and motility, as well as cellular morphology. Overexpression of the microtubule-destabilizing phosphoprotein stathmin is frequent in human malignancies and represents a promising therapeutic target. Although stathmin inhibition gives rise to antineoplastic effects, additional and functionally redundant microtubule-interacting proteins may attenuate the efficiency of this therapeutic approach. We have systematically analyzed the expression and potential protumorigenic effects of stathmin family members in human non–small cell lung cancer (NSCLC). Both stathmin and stathmin-like 3 (SCLIP) were overexpressed in adenocarcinoma as well as squamous cell carcinoma (SCC) tissues and induced tumor cell proliferation, migration, and matrix invasion in respective cell lines. Accordingly, reduced stathmin and SCLIP levels affected cell morphology and were associated with a less malignant phenotype. Combined inhibition of both factors caused additive effects on tumor cell motility, indicating partial functional redundancy. Because stathmin and SCLIP expression significantly correlated in NSCLC tissues, we searched for common upstream regulators and identified the far upstream sequence element-binding protein-1 (FBP-1) as a pivotal inducer of several stathmin family members. Our results indicate that the coordinated overexpression of microtubule-destabilizing factors by FBP-1 is a critical step to facilitate microtubule dynamics and subsequently increases proliferation and motility of tumor cells. [Cancer Res 2009;69(6):2234–43]
Data from Control of HIF-1α Expression by eIF2α Phosphorylation–Mediated Translational Repression
Authors: Zhu Keyi , Chan WaiKin , Heymach John , Wilkinson Miles , McConkey David J.
Published: March 2023

Abstract
Hypoxia inducible factor 1α (HIF-1α) plays a central role in regulating tumor angiogenesis via its effects on vascular endothelial growth factor (VEGF) transcription, and its expression is regulated through proteasome-mediated degradation. Paradoxically, previous studies have shown that proteasome inhibitors (PI) block tumor angiogensis by reducing VEGF expression, but the mechanisms have not been identified. Here, we report that PIs down-regulated HIF-1α protein levels and blocked HIF-1α transcriptional activity in human prostate cancer cells. PIs induced phosphorylation of the translation initiation factor 2α (eIF2α), which caused general translational repression to inhibit HIF-1α expression. Furthermore, PIs induced HIF-1α accumulation in LNCaP-Pro5 cells depleted of eIF2α via siRNA transfection and in MEFs expressing a phosphorylation-deficient mutant form of eIF2α. Finally, PIs failed to induce eIF2α phosphorylation or translational attenuation in DU145 or 253JB-V cells, and, in these cells, PIs promoted HIF-1α accumulation. Our data established that PIs down-regulated HIF-1α expression in cells that display activation of the unfolded protein response by stimulating phosphorylation of eIF2α and inhibiting HIF-1α translation. [Cancer Res 2009;69(5):1836–43]
Data from WNT16B Is a New Marker of Cellular Senescence That Regulates p53 Activity and the Phosphoinositide 3-Kinase/AKT Pathway
Authors: Binet Romuald , Ythier Damien , Robles Ana I. , Collado Manuel , Larrieu Delphine , Fonti Claire , Brambilla Elisabeth , Brambilla Christian , Serrano Manuel , Harris Curtis C. , Pedeux Rémy
Published: March 2023

Abstract
Senescence is a tumor suppression mechanism that is induced by several stimuli, including oncogenic signaling and telomere shortening, and controlled by the p53/p21WAF1 signaling pathway. Recently, a critical role for secreted factors has emerged, suggesting that extracellular signals are necessary for the onset and maintenance of senescence. Conversely, factors secreted by senescent cells may promote tumor growth. By using expression profiling techniques, we searched for secreted factors that were overexpressed in fibroblasts undergoing replicative senescence. We identified WNT16B, a member of the WNT family of secreted proteins. We found that WNT16B is overexpressed in cells undergoing stress-induced premature senescence and oncogene-induced senescence in both MRC5 cell line and the in vivo murine model of K-RasV12–induced senescence. By small interfering RNA experiments, we observed that both p53 and WNT16B are necessary for the onset of replicative senescence. WNT16B expression is required for the full transcriptional activation of p21WAF1. Moreover, WNT16B regulates activation of the phosphoinositide 3-kinase (PI3K)/AKT pathway. Overall, we identified WNT16B as a new marker of senescence that regulates p53 activity and the PI3K/AKT pathway and is necessary for the onset of replicative senescence. [Cancer Res 2009;69(24):9183–91]
Data from Tumor-Infiltrating Regulatory Dendritic Cells Inhibit CD8+ T Cell Function via l-Arginine Metabolism
Authors: Norian Lyse A. , Rodriguez Paulo C. , O'Mara Leigh A. , Zabaleta Jovanny , Ochoa Augusto C. , Cella Marina , Allen Paul M.
Published: March 2023

Abstract
Dendritic cells (DC) have a critical effect on the outcome of adaptive immune responses against growing tumors. Whereas it is generally assumed that the presence of phenotypically mature DCs should promote protective antitumor immunity, evidence to the contrary does exist. We describe here a novel mechanism by which tumor-infiltrating dendritic cells (TIDC) actively contribute to the suppression of protective CD8+ T-cell–based antitumor immunity. Using the BALB/NeuT model of spontaneously arising mammary carcinoma, we found that canonical MHC II+/CD11b+/CD11chigh TIDCs act as regulatory DCs to suppress CD8+ T-cell function, resulting in diminished T-cell–based antitumor immunity in vivo. Stimulation of naive T cells with regulatory TIDCs resulted in an altered cell fate program characterized by minimal T-cell expansion, impaired IFNγ production, and anergy. Suppression by regulatory TIDCs overcame stimulatory signals provided by standard DCs, occurred in the absence of cognate interactions with T cells, and was mediated primarily by arginase metabolism of l-arginine. Immunosuppressive TIDCs were found in every murine tumor type examined and were phenotypically distinct from tumor-infiltrating CD11cint-low/CD11b+/Gr-1+ myeloid-derived suppressor cells. Thus, within the tumor microenvironment, MHC II+ TIDCs can function as potent suppressors of CD8+ T-cell immunity. [Cancer Res 2009;69(7):3086–94]
Data from Steroid Sulfatase and Estrogen Sulfotransferase in Colon Carcinoma: Regulators of Intratumoral Estrogen Concentrations and Potent Prognostic Factors
Authors: Sato Ryuichiro , Suzuki Takashi , Katayose Yu , Miura Koh , Shiiba Kenichi , Tateno Hiroo , Miki Yasuhiro , Akahira Junichi , Kamogawa Yukiko , Nagasaki Shuji , Yamamoto Kuniharu , Ii Takayuki , Egawa Shinichi , Evans Dean B. , Unno Michiaki , Sasano Hironobu
Published: March 2023

Abstract
Previous epidemiologic and in vitro studies have indicated a potential involvement of estrogens in the pathogenesis of human colon carcinoma, but the precise roles of estrogens have remained largely unknown. Therefore, in this study, we first measured intratumoral concentrations of estrogens in 53 colon carcinomas using liquid chromatography-electrospray ionization tandem mass spectrometry (LC-ESI-MS). Tissue concentrations of total estrogen [estrone (E1) + estradiol] and E1 were significantly (2.0- and 2.4-fold, respectively) higher in colon carcinoma tissues than in nonneoplastic colonic mucosa (n = 31), and higher intratumoral concentrations of total estrogen and E1 were significantly associated with adverse clinical outcome. Intratumoral concentration of total estrogen was significantly associated with the combined status of steroid sulfatase (STS) and estrogen sulfotransferase (EST), but not with that of aromatase. Thus, we subsequently examined the STS/EST status in 328 colon carcinomas using immunohistochemistry. Immunoreactivities for STS and EST were detected in 61% and 44% of the cases, respectively. The −/+ group of the STS/EST status was inversely associated with Dukes' stage, depth of invasion, lymph node metastasis, and distant metastasis and positively correlated with Ki-67 labeling index of the carcinomas. In addition, this −/+ group had significantly longer survival, and a multivariate analysis revealed the STS/EST status as an independent prognostic factor. Results from our present study showed that the STS/EST status of carcinoma tissue determined intratumoral estrogen levels and could be a significant prognostic factor in colon carcinoma, suggesting that estrogens are locally produced mainly through the sulfatase pathway and play important roles in the progression of the disease. [Cancer Res 2009;69(3):914–22]
Data from Global Histone Modifications in Breast Cancer Correlate with Tumor Phenotypes, Prognostic Factors, and Patient Outcome
Authors: Elsheikh Somaia E. , Green Andrew R. , Rakha Emad A. , Powe Des G. , Ahmed Rabab A. , Collins Hilary M. , Soria Daniele , Garibaldi Jonathan M. , Paish Claire E. , Ammar Amr A. , Grainge Matthew J. , Ball Graham R. , Abdelghany Magdy K. , Martinez-Pomares Luisa , Heery David M. , Ellis Ian O.
Published: March 2023

Abstract
Post-translational histone modifications are known to be altered in cancer cells, and loss of selected histone acetylation and methylation marks has recently been shown to predict patient outcome in human carcinoma. Immunohistochemistry was used to detect a series of histone lysine acetylation (H3K9ac, H3K18ac, H4K12ac, and H4K16ac), lysine methylation (H3K4me2 and H4K20me3), and arginine methylation (H4R3me2) marks in a well-characterized series of human breast carcinomas (n = 880). Tissue staining intensities were assessed using blinded semiquantitative scoring. Validation studies were done using immunofluorescence staining and Western blotting. Our analyses revealed low or absent H4K16ac in the majority of breast cancer cases (78.9%), suggesting that this alteration may represent an early sign of breast cancer. There was a highly significant correlation between histone modifications status, tumor biomarker phenotype, and clinical outcome, where high relative levels of global histone acetylation and methylation were associated with a favorable prognosis and detected almost exclusively in luminal-like breast tumors (93%). Moderate to low levels of lysine acetylation (H3K9ac, H3K18ac, and H4K12ac), lysine (H3K4me2 and H4K20me3), and arginine methylation (H4R3me2) were observed in carcinomas of poorer prognostic subtypes, including basal carcinomas and HER-2-positive tumors. Clustering analysis identified three groups of histone displaying distinct pattern in breast cancer, which have distinct relationships to known prognostic factors and clinical outcome. This study identifies the presence of variations in global levels of histone marks in different grades, morphologic types, and phenotype classes of invasive breast cancer and shows that these differences have clinical significance. [Cancer Res 2009;69(9):3802–9]