bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Tumor Necrosis Factor α Mediates Homogeneous Distribution of Liposomes in Murine Melanoma that Contributes to a Better Tumor Response
Authors: Seynhaeve Ann L.B. , Hoving Saske , Schipper Debby , Vermeulen Cindy E. , aan de Wiel-Ambagtsheer Gisela , van Tiel Sandra T. , Eggermont Alexander M.M. , ten Hagen Timo L.M.
Published: March 2023

Abstract
Successful treatment of solid tumors with chemotherapeutics requires that adequate levels reach the tumor cells. Tumor vascular normalization has been proposed to enhance drug delivery and improve tumor response to chemotherapy. Differently, augmenting leakage of the tumor-associated vasculature, and as such enhance vascular abnormality, may improve tumor response as well. In the present study, we show that addition of low-dose tumor necrosis factor α (TNF) to systemic injections with pegylated long circulating liposomes augmented the tumor accumulation of these liposomes 5- to 6-fold, which strongly correlated with enhanced tumor response. Using intravital microscopy, we could study the liposomal distribution inside the tumor in more detail. Especially 100 nm liposomes effectively extravasate in the surrounding tumor tissue in the presence of TNF and this occurred without any effect on tumor vascular density, branching, and diameter. Next to that, we observed in living animals that tumor cells take up the liposomes intact, followed by intracellular degradation. To our knowledge, this is an unprecedented observation. Taken together, TNF renders more tumor vessels permeable, leading to a more homogeneous distribution of the liposomes throughout the tumor, which is crucial for an optimal tumor response. We conclude that delivery of nanoparticulate drug formulations to solid tumor benefits from augmenting the vascular leakage through vascular manipulation with vasoactive drugs like TNF. [Cancer Res 2007;67(19):9455–62]
Data from A Novel Bioluminescent Mouse Model and Effective Therapy for Adult T-Cell Leukemia/Lymphoma
Authors: Shu Sherry T. , Nadella Murali V.P. , Dirksen Wessel P. , Fernandez Soledad A. , Thudi Nanda K. , Werbeck Jillian L. , Lairmore Michael D. , Rosol Thomas J.
Published: March 2023

Abstract
Adult T-cell /lymphomaleukemia (ATLL) is caused by human T-cell lymphotropic virus type 1 (HTLV-1). Approximately 80% of ATLL patients develop humoral hypercalcemia of malignancy (HHM), a life-threatening complication leading to a poor prognosis. Parathyroid hormone–related protein (PTHrP) and macrophage inflammatory protein-1α (MIP-1α) are important factors in the pathogenesis of HHM in ATLL and the expression of PTHrP can be activated by nuclear factor κB (NF-κB). NF-κB is constitutively activated in ATLL cells and is essential for leukemogenesis including transformation of lymphocytes infected by HTLV-1. Our goal was to evaluate the effects of NF-κB disruption by a proteasomal inhibitor (PS-341) and osteoclastic inhibition by zoledronic acid (Zol) on the development of ATLL and HHM using a novel bioluminescent mouse model. We found that PS-341 decreased cell viability, increased apoptosis, and down-regulated PTHrP expression in ATLL cells in vitro. To investigate the in vivo efficacy, nonobese diabetic/severe combined immunodeficient (NOD/SCID) mice were xenografted with ATLL cells and treated with vehicle control, PS-341, Zol, or a combination of PS-341 and Zol. Bioluminescent imaging and tumor cell count showed a significant reduction in tumor burden in mice from all treatment groups. All treatments also significantly reduced the plasma calcium concentrations. Zol treatment increased trabecular bone volume and decreased osteoclast parameters. PS-341 reduced PTHrP and MIP-1α expression in tumor cells in vivo. Our results indicate that both PS-341 and Zol are effective treatments for ATLL and HHM, which are refractory to conventional therapy. [Cancer Res 2007;67(24):11859–66]
Data from Metallothionein Expression Is Suppressed in Primary Human Hepatocellular Carcinomas and Is Mediated through Inactivation of CCAAT/Enhancer Binding Protein α by Phosphatidylinositol 3-Kinase Signaling Cascade
Authors: Datta Jharna , Majumder Sarmila , Kutay Huban , Motiwala Tasneem , Frankel Wendy , Costa Robert , Cha Hyuk C. , MacDougald Ormond A. , Jacob Samson T. , Ghoshal Kalpana
Published: March 2023

Abstract
Reactive oxygen species (ROS) resulting from chronic inflammation cause liver injury leading to transformation of regenerating hepatocytes. Metallothioneins (MT), induced at high levels by oxidative stress, are potent scavengers of ROS. Here, we report that the levels of MT-1 and MT-2A are drastically reduced in primary human hepatocellular carcinomas (HCCs) and in diethylnitrosamine-induced liver tumors in mice, which is primarily due to transcriptional repression. Expression of the transcription factor, MTF-1, essential for MT expression, and its target gene Zn-T1 that encodes the zinc transporter-1 was not significantly altered in HCCs. Inhibitors of both phosphatidylinositol 3-kinase (PI3K) and its downstream target AKT increased expression of MT genes in HCC cells but not in liver epithelial cells. Suppression of MT-1 and MT-2A by ectopic expression of the constitutively active PI3K or AKT and their up-regulation by dominant-negative PI3K or AKT mutant confirmed negative regulation of MT expression by PI3K/AKT signaling pathway. Further, treatment of cells with a specific inhibitor of glycogen synthase kinase-3 (GSK-3), a downstream effector of PI3K/AKT, inhibited MT expression specifically in HCC cells. Short interfering RNA–mediated depletion of CCAAT/enhancer binding protein α (C/EBPα), a target of GSK-3, impeded MT expression, which could not be reversed by PI3K inhibitors. DNA binding activity of C/EBPα and its phosphorylation at T222 and T226 by GSK-3 are required for MT expression. MTF-1 and C/EBPα act in concert to increase MT-2A expression, which probably explains the high level of MT expression in the liver. This study shows the role of PI3K/AKT signaling pathway and C/EBPα in regulation of MT expression in hepatocarcinogenesis. [Cancer Res 2007;67(6):2736–46]
Data from Aurora-A Kinase Regulates Breast Cancer–Associated Gene 1 Inhibition of Centrosome-Dependent Microtubule Nucleation
Authors: Sankaran Satish , Crone Donna E. , Palazzo Robert E. , Parvin Jeffrey D.
Published: March 2023

Abstract
Breast cancer–associated gene 1 (BRCA1) regulates the duplication and the function of centrosomes in breast cells. We have previously shown that BRCA1 ubiquitin ligase activity directly inhibits centrosome-dependent microtubule nucleation. However, there is a paradox because centrosome microtubule nucleation potential is highest during mitosis, a phase when BRCA1 is most abundant at the centrosome. In this study, we resolve this conundrum by testing whether centrosomes from cells in M phase are regulated differently by BRCA1 when compared with other phases of the cell cycle. We observed that BRCA1-dependent inhibition of centrosome microtubule nucleation was high in S phase but was significantly lower during M phase. The cell cycle–specific effects of BRCA1 on centrosome-dependent microtubule nucleation were detected in living cells and in cell-free experiments using centrosomes purified from cells at specific stages of the cell cycle. We show that Aurora-A kinase modulates the BRCA1 inhibition of centrosome function by decreasing the E3 ubiquitin ligase activity of BRCA1. In addition, dephosphorylation of BRCA1 by protein phosphatase 1α enhances the E3 ubiquitin ligase activity of BRCA1. These observations reveal that the inhibition of centrosome microtubule nucleation potential by the BRCA1 E3 ubiquitin ligase is controlled by Aurora-A kinase and protein phosphatase 1α–mediated phosphoregulation through the different phases of the cell cycle. [Cancer Res 2007;67(23):11186–94]
Data from Frequent Loss of Brm Expression in Gastric Cancer Correlates with Histologic Features and Differentiation State
Authors: Yamamichi Nobutake , Inada Ken-ichi , Ichinose Masao , Yamamichi-Nishina Mitsue , Mizutani Taketoshi , Watanabe Hirotaka , Shiogama Kazuya , Fujishiro Mitsuhiro , Okazaki Takuya , Yahagi Naohisa , Haraguchi Takeshi , Fujita Shuji , Tsutsumi Yutaka , Omata Masao , Iba Hideo
Published: March 2023

Abstract
The mammalian SWI/SNF chromatin remodeling complex, an essential epigenetic regulator, contains either a single Brm or BRG1 molecule as its catalytic subunit. We observed frequent loss of Brm expression but not of BRG1 in human gastric cancer cell lines. Treatment with histone deacetylase inhibitor rescued Brm expression, indicating epigenetic regulation of this gene, and an RNA interference–based colony formation assay revealed antioncogenic properties of Brm. Brm immunostaining of 89 primary gastric cancers showed an obvious reduction in 60 cases (67%) and a severe decrease in 37 cases (42%). Loss of Brm is frequent in the major gastric cancer types (well- or moderately-differentiated tubular adenocarcinoma and poorly-differentiated adenocarcinoma) and positively correlates with the undifferentiated state. Among the minor gastric cancer types, Brm expression persists in signet-ring cell carcinoma and mucinous adenocarcinoma, but a marked decrease is observed in papillary adenocarcinoma. Intestinal metaplasia never shows decreased expression, indicating that Brm is a valid marker of gastric oncogenesis. In contrast, BRG1 is retained in most cases; a concomitant loss of BRG1 and Brm is rare in gastric cancer, contrary to other malignancies. We further show that Brm is required for villin expression, a definitive marker of intestinal metaplasia and differentiation. Via regulating such genes important for gut differentiation, Brm should play significant roles in determining the histologic features of gastric malignancy. [Cancer Res 2007;67(22):10727–35]
Data from Elucidating the Function of Secreted Maspin: Inhibiting Cathepsin D–Mediated Matrix Degradation
Authors: Khalkhali-Ellis Zhila , Hendrix Mary J.C.
Published: March 2023

Abstract
Cellular interaction with the extracellular milieu plays a significant role in normal biological and pathologic processes. Excessive degradation of basement membrane matrix by proteolytic enzymes is a hallmark of tumor invasion and metastasis, and aspartyl proteinase cathepsin D is implicated as a major contributor to this process. Maspin, a non-inhibitory serpin, plays an important role in mammary gland development and remodeling. Expression of Maspin is decreased in primary tumors and lost in metastatic lesions. Maspin is mostly cytoplasmic and is partially secreted; however, the fate and function of secreted Maspin has remained mostly unexplored. We hypothesized that secreted Maspin is incorporated into the matrix deposited by normal mammary epithelial cells and thus could play a critical role in cathepsin D–mediated matrix degradation and remodeling of mammary tissue. In the absence of Maspin, as is the case with most cancer cells, matrix degradation proceeds unrestricted, thus facilitating the progression to metastasis. To test this, we employed an in vitro model where gels containing both types I and IV collagen were preconditioned with normal mammary epithelial cells to allow the incorporation of secreted Maspin. This conditioned matrix was used to examine cathepsin D–mediated collagen degradation by human breast cancer cell lines. Our results indicate that secretion of Maspin and its deposition into the extracellular milieu play an important role in matrix degradation. In this capacity, Maspin could potentially regulate mammary tissue remodeling occurring under normal and pathologic conditions. In addition, these findings could have a potential effect on future therapeutic intervention strategies for breast cancer. [Cancer Res 2007;67(8):3535–9]
Data from Frequently Methylated Tumor Suppressor Genes in Head and Neck Squamous Cell Carcinoma
Authors: Bennett Kristi L. , Karpenko Matthew , Lin Mau-ting , Claus Rainer , Arab Khelifa , Dyckhoff Gerhard , Plinkert Peter , Herpel Esther , Smiraglia Dominic , Plass Christoph
Published: March 2023

Abstract
Head and neck squamous cell carcinoma (HNSCC) is a very aggressive cancer. In advanced stages, the patient has poor chances of receiving effective treatment, and survival rates are low. To facilitate timely diagnosis and improve treatment, elucidation of early detection markers is crucial. DNA methylation markers are particularly advantageous because DNA methylation is an early event in tumorigenesis, and the epigenetic modification, 5-methylcytosine, is a stable mark. A genome-wide screen using Restriction Landmark Genomic Scanning found a set of genes that are most commonly methylated in head and neck cancers. Five candidate genes: septin 9 (SEPT9), sodium-coupled monocarboxylate transporter 1 (SLC5A8), functional smad-suppressing element on chromosome 18 (FUSSEL18), early B-cell factor 3 (EBF3), and iroquois homeobox 1 (IRX1) were methylated in 27% to 67% of the HNSCC patient samples tested. Furthermore, ∼50% of the methylated tumor samples shared methylation between two of the five genes (most commonly between EBF3 and IRX1), and 15% shared methylation between three of the five genes. Expression analysis revealed candidate gene down-regulation in 25% to 93% of the HNSCC samples, and 5-aza-2′-deoxycytidine treatment was able to restore expression in at least 2 of 5 HNSCC cell lines for all of the genes tested. Overexpression of the three most frequently down-regulated candidates, SLC5A8, IRX1, and EBF3, validated their tumor suppressor potential by growth curve analysis and colony formation assay. Interestingly, all of the candidates identified may be involved in the transforming growth factor β signaling pathway, which is often disrupted in HNSCC. [Cancer Res 2008;68(12):4494–99]
Data from RAD51 Up-regulation Bypasses BRCA1 Function and Is a Common Feature of BRCA1-Deficient Breast Tumors
Authors: Martin Richard W. , Orelli Brian J. , Yamazoe Mitsuyoshi , Minn Andy J. , Takeda Shunichi , Bishop Douglas K.
Published: March 2023

Abstract
The breast cancer susceptibility gene BRCA1 encodes a large protein thought to contribute to a variety of cellular processes, although the critical determinants of BRCA1-deficient tumorigenesis remain unclear. Given that BRCA1 is required for cell proliferation, suppressor mutations are believed to modify BRCA1 phenotypes and contribute to the etiology of BRCA1-deficient tumors. Here, we show that overexpression of the homologous recombinase RAD51 in a DT40 BRCA1Δ/Δ mutant rescues defects in proliferation, DNA damage survival, and homologous recombination (HR). In addition, epistasis analysis with BRCA1 and the DNA end-joining factor KU70 indicates that these factors operate independently of one another to repair double-strand breaks. Consistent with this genetic finding, cell synchronization studies show that the ability of BRCA1 to promote radioresistance is restricted to the late S and G2 phases of the cell cycle, as predicted for genes whose function is specific to homology-mediated repair rather than nonhomologous end-joining. Notably, retrospective analyses of microarray expression data reveal elevated expression of RAD51 and two of its late-acting cofactors, RAD54 and RAD51AP1, in BRCA1-deficient versus sporadic breast tumors. Taken together, our results indicate that up-regulation of HR provides a permissive genetic context for cells lacking BRCA1 function by circumventing its requirement in RAD51 subnuclear assembly. Furthermore, the data support a model in which enhanced HR activity contributes to the etiology of BRCA1-deficient tumors. [Cancer Res 2007;67(20):9658–65]
Data from Overexpression of N-Myc Rapidly Causes Acute Myeloid Leukemia in Mice
Authors: Kawagoe Hiroyuki , Kandilci Ayten , Kranenburg Tanya A. , Grosveld Gerard C.
Published: March 2023

Abstract
N-MYC encodes a basic helix-loop-helix/leucine zipper (bHLH/LZ) transcription factor that is frequently overexpressed in human neuroblastoma. N-MYC overexpression has also been reported in human acute myeloid leukemias (AML), which we show here is a frequent event. Myeloid cells in N-Myc–overexpressing mouse bone marrow hyperproliferate but those in c-MYC–overexpressing bone marrow do not. The NH2-terminal transactivation domain, nuclear localization signal, and bHLH/LZ domain of N-Myc are essential for this effect. Microarray analysis revealed 969 differentially expressed genes between N-Myc– and c-MYC–overexpressing myeloid cells. N-Myc–overexpressing cells showed decreased transforming growth factor β signaling and increased c-Jun-NH2-kinase signaling, both of which are associated with proliferation and leukemic transformation of myeloid cells. Mice transplanted with bone marrow expressing wild-type N-Myc developed clonal and transplantable AML after ∼1 month; those transplanted with bone marrow expressing mutant N-Myc did not. Twist, a known suppressor of the p19Arf/p53 pathway, was up-regulated in all tumors. These results show that N-Myc overexpression is highly oncogenic in mouse myeloid cells and suggest that N-MYC up-regulation contributes to human myeloid leukemogenesis. [Cancer Res 2007;67(22):10677–85]
Data from Deregulated CDC25A Expression Promotes Mammary Tumorigenesis with Genomic Instability
Authors: Ray Dipankar , Terao Yasuhisa , Fuhrken Peter G. , Ma Zhi-Qing , DeMayo Francesco J. , Christov Konstantin , Heerema Nyla A. , Franks Roberta , Tsai Sophia Y. , Papoutsakis Eleftherios T. , Kiyokawa Hiroaki
Published: March 2023

Abstract
Checkpoint pathways help cells maintain genomic integrity, delaying cell cycle progression in response to various risks of fidelity, such as genotoxic stresses, compromised DNA replication, and impaired spindle control. Cancer cells frequently exhibit genomic instability, and recent studies showed that checkpoint pathways are likely to serve as a tumor-suppressive barrier in vivo. The cell cycle–promoting phosphatase CDC25A is an activator of cyclin-dependent kinases and one of the downstream targets for the CHK1-mediated checkpoint pathway. Whereas CDC25A overexpression is observed in various human cancer tissues, it has not been determined whether deregulated CDC25A expression triggers or promotes tumorigenesis in vivo. Here, we show that transgenic expression of CDC25A cooperates markedly with oncogenic ras or neu in murine mammary tumorigenesis. MMTV-CDC25A transgenic mice exhibit alveolar hyperplasia in the mammary tissue but do not develop spontaneous mammary tumors. The MMTV-CDC25A transgene markedly shortens latency of tumorigenesis in MMTV-ras mice. The MMTV-CDC25A transgene also accelerates tumor growth in MMTV-neu mice with apparent cell cycle miscoordination. CDC25A-overexpressing tumors, which invade more aggressively, exhibit various chromosomal aberrations on fragile regions, including the mouse counterpart of human 1p31-36, according to array-based comparative genomic hybridization and karyotyping. The chromosomal aberrations account for substantial changes in gene expression profile rendered by transgenic expression of CDC25A, including down-regulation of Trp73. These data indicate that deregulated control of cellular CDC25A levels leads to in vivo genomic instability, which cooperates with the neu-ras oncogenic pathway in mammary tumorigenesis. [Cancer Res 2007;67(3):984–91]
Data from The Tyrosine Phosphatase Shp2 Interacts with NPM-ALK and Regulates Anaplastic Lymphoma Cell Growth and Migration
Authors: Voena Claudia , Conte Chiara , Ambrogio Chiara , Boeri Erba Elisabetta , Boccalatte Francesco , Mohammed Shabaz , Jensen Ole N. , Palestro Giorgio , Inghirami Giorgio , Chiarle Roberto
Published: March 2023

Abstract
Anaplastic large cell lymphomas (ALCL) are mainly characterized by the reciprocal translocation t(2;5)(p23;q35) that involves the anaplastic lymphoma kinase (ALK) gene and generates the fusion protein NPM-ALK with intrinsic tyrosine kinase activity. NPM-ALK triggers several signaling cascades, leading to increased cell growth, resistance to apoptosis, and changes in morphology and migration of transformed cells. To search for new NPM-ALK interacting molecules, we developed a mass spectrometry–based proteomic approach in HEK293 cells expressing an inducible NPM-ALK and identified the tyrosine phosphatase Shp2 as a candidate substrate. We found that NPM-ALK was able to bind Shp2 in coprecipitation experiments and to induce its phosphorylation in the tyrosine residues Y542 and Y580 both in HEK293 cells and ALCL cell lines. In primary lymphomas, antibodies against the phosphorylated tyrosine Y542 of Shp2 mainly stained ALK-positive cells. In ALCL cell lines, Shp2-constitutive phosphorylation was dependent on NPM-ALK, as it significantly decreased after short hairpin RNA (shRNA)–mediated NPM-ALK knock down. In addition, only the constitutively active NPM-ALK, but not the kinase dead NPM-ALKK210R, formed a complex with Shp2, Gab2, and growth factor receptor binding protein 2 (Grb2), where Grb2 bound to the phosphorylated Shp2 through its SH2 domain. Shp2 knock down by specific shRNA decreased the phosphorylation of extracellular signal-regulated kinase 1/2 and of the tyrosine residue Y416 in the activation loop of Src, resulting in impaired ALCL cell proliferation and growth disadvantage. Finally, migration of ALCL cells was reduced by Shp2 shRNA. These findings show a direct involvement of Shp2 in NPM-ALK lymphomagenesis, highlighting its critical role in lymphoma cell proliferation and migration. [Cancer Res 2007;67(9):4278–86]
Data from Identification of Candidate Molecular Markers Predicting Sensitivity in Solid Tumors to Dasatinib: Rationale for Patient Selection
Authors: Huang Fei , Reeves Karen , Han Xia , Fairchild Craig , Platero Suso , Wong Tai W. , Lee Francis , Shaw Peter , Clark Edwin
Published: March 2023

Abstract
Dasatinib is a multitargeted kinase inhibitor that was recently approved for the treatment of chronic myelogenous leukemia and Philadelphia chromosome–positive acute lymphoblastic leukemia with resistance or intolerance to prior therapy. It is also in clinical trials for treating patients with solid tumors. The identification of molecular markers predictive of response to dasatinib could assist in clinical development by selecting patients most likely to derive clinical benefit. Using baseline gene expression profiling of a panel of 23 breast cancer cell lines, we identified genomic signatures highly correlated with in vitro sensitivity to dasatinib. The ability of these signatures to predict dasatinib sensitivity was further confirmed and validated in independent test cell lines. A six-gene model was used to correctly predict dasatinib sensitivity in 11 out of 12 (92%) additional breast and 19 out of 23 (83%) lung cancer cell lines. Quantitative real-time PCR and immunohistochemical assays further confirmed the differential expression pattern of selected markers. Finally, these gene signatures were observed in a subset of primary breast, lung, and ovarian tumors suggesting potential utility in patient selection. The subset of breast cancer patients expressing the dasatinib-sensitive signature includes a distinct clinical and molecular subgroup: the so-called “triple negative” (i.e., estrogen receptor–negative, progesterone receptor–negative, and HER2-negative) or “basal” breast cancer subtype. This patient population has a poor prognosis and currently has few effective treatment options. Our results implicate that dasatinib may represent a valuable treatment option in this difficult-to-treat population. To test this hypothesis, clinical studies are now under way to determine the activity of dasatinib in these patients. [Cancer Res 2007;67(5):2226–38]
Data from EphB4 Overexpression in B16 Melanoma Cells Affects Arterial-Venous Patterning in Tumor Angiogenesis
Authors: Huang Xiaoyong , Yamada Yoshihiro , Kidoya Hiroyasu , Naito Hisamichi , Nagahama Yumi , Kong Lingyu , Katoh Shin-Ya , Li Weng-lin , Ueno Masaya , Takakura Nobuyuki
Published: March 2023

Abstract
EphB4 receptor and its ligand ephrinB2 play an important role in vascular development during embryogenesis. In blood vessels, ephrinB2 is expressed in arterial endothelial cells (EC) and mesenchymal supporting cells, whereas EphB4 is only expressed in venous ECs. Previously, we reported that OP9 stromal cells, which support the development of both arterial and venous ECs, in which EphB4 was overexpressed, could inhibit ephrinB2-positive (ephrinB2+) EC development in an embryonic tissue organ culture system. Although the EphB4 receptor is expressed in a variety of tumor cells, its exact function in regulating tumor progression has not been clearly shown. Here we found that overexpression of EphB4 in B16 melanoma cells suppressed tumor growth in a s.c. transplantation tumor model. Histologic examination of these tumors revealed that EphB4 overexpression in B16 cells selectively suppressed arterial ephrinB2+ EC development. By coculturing ephrinB2-expressing SV40-transformed mouse ECs (SVEC) with EphB4-overexpressing B16 cells, we found that EphB4 induced the apoptosis of SVECs. However, ephrinB2 did not induce the apoptosis of EphB4-overexpressing B16 cells. Based on results from these experiments, we concluded that EphB4 overexpression in B16 tumor cells suppresses the survival of arterial ECs in tumors by a reverse signaling via ephrinB2. [Cancer Res 2007;67(20):9800–8]
Data from Integrated Profiling of Basal and Luminal Breast Cancers
Authors: Adélaïde José , Finetti Pascal , Bekhouche Ismahane , Repellini Laetitia , Geneix Jeannine , Sircoulomb Fabrice , Charafe-Jauffret Emmanuelle , Cervera Nathalie , Desplans Jérôme , Parzy Daniel , Schoenmakers Eric , Viens Patrice , Jacquemier Jocelyne , Birnbaum Daniel , Bertucci François , Chaffanet Max
Published: March 2023

Abstract
Basal and luminal are two molecular subtypes of breast cancer with opposite histoclinical features. We report a combined, high-resolution analysis of genome copy number and gene expression in primary basal and luminal breast cancers. First, we identified and compared genomic alterations in 45 basal and 48 luminal tumors by using 244K oligonucleotide array comparative genomic hybridization (aCGH). We found various genome gains and losses and rare high-level gene amplifications that may provide therapeutic targets. We show that gain of 10p is a new alteration in basal breast cancer and that a subregion of the 8p12 amplification is specific of luminal tumors. Rare high-level amplifications contained BCL2L2, CCNE, EGFR, FGFR2, IGF1R, NOTCH2, and PIK3CA. Potential gene breaks involved ETV6 and FLT3. Second, we analyzed both aCGH and gene expression profiles for 42 basal and 32 luminal breast cancers. The results support the existence of specific oncogenic pathways in basal and luminal breast cancers, involving several potential oncogenes and tumor suppressor genes (TSG). In basal tumors, 73 candidate oncogenes were identified in chromosome regions 1q21-23, 10p14, and 12p13 and 28 candidate TSG in regions 4q32-34 and 5q11-23. In luminal breast cancers, 33 potential oncogenes were identified in 1q21-23, 8p12-q21, 11q13, and 16p12-13 and 61 candidate TSG in 16q12-13, 16q22-24, and 17p13. HORMAD1 (P = 6.5 × 10−5) and ZNF703 (P = 7 × 10−4) were the most significant basal and luminal potential oncogenes, respectively. Finally, among 10p candidate oncogenes associated with basal subtype, we validated CDC123/C10orf7 protein as a basal marker. [Cancer Res 2007;67(24):11565–75]
Data from Phosphatidylcholine-Specific Phospholipase C Activation in Epithelial Ovarian Cancer Cells
Authors: Spadaro Francesca , Ramoni Carlo , Mezzanzanica Delia , Miotti Silvia , Alberti Paola , Cecchetti Serena , Iorio Egidio , Dolo Vincenza , Canevari Silvana , Podo Franca
Published: March 2023

Abstract
Elucidation of the mechanisms responsible for aberrant phosphatidylcholine (PC) metabolism in cancer cells may allow identification of novel biomarkers of tumor progression and design of new targeted anticancer therapies. We recently reported up-regulation of PC-specific phospholipases in epithelial ovarian cancer cells (EOC) compared with nontumoral (normal or immortalized) counterparts (EONT). In the present study, we focused, in the same cell systems, on levels, subcellular localization, and activity of PC-specific phospholipase C (PC-PLC), for which a key role in cell proliferation, differentiation, and apoptosis has been shown in several mammalian cells. A 66-kDa PC-PLC isoform, detected in nuclear and cytoplasmic compartments of both EOC and EONT cells, accumulated on the external plasma membrane of cancer cells only, where it colocalized with β1 integrin, in nonraft membrane domains. PC-PLC activity was 3-fold higher in total cell lysates and 5-fold higher in membrane-enriched fractions of EOC compared with EONT cells. Serum deprivation induced in EOC, but not in EONT, cells a 3-fold decrease in PC-PLC activity, associated with a 40% drop in S-phase fraction. The recovery of both variables to their original levels in serum-restimulated (or lysophosphatidic acid–restimulated) EOC cells was strongly delayed, for at least 24 h, in the presence of the PC-PLC inhibitor tricyclodecan-9-yl-potassium xanthate (D609). The S-phase of serum-restimulated EONT cells was not sensitive to D609. These findings warrant further investigations on the role of PC-PLC and on the effects of its inhibition on the pathways responsible for constitutive EOC cell stimulation and cell proliferation. [Cancer Res 2008;68(16):6541–9]
Data from Live Attenuated Listeria Monocytogenes Effectively Treats Hepatic Colorectal Cancer Metastases and Is Strongly Enhanced by Depletion of Regulatory T Cells
Authors: Yoshimura Kiyoshi , Laird Lindsay S. , Chia Christina Y. , Meckel Kristen F. , Slansky Jill E. , Thompson John M. , Jain Ajay , Pardoll Drew M. , Schulick Richard D.
Published: March 2023

Abstract
The liver represents a major and frequently sole site of metastases for many types of cancer, particularly gastrointestinal cancers. We showed previously that coadministration of an engineered hepatic-targeting Listeria monocytogenes (LM) with a cancer vaccine enhanced the antitumor effect of vaccine-induced T cells selectively against hepatic metastases. Here, we show that administration of multiple doses of LM, in the absence of vaccine, generates therapeutic responses against hepatic metastases. LM treatment of mice bearing hepatic metastases induced tumor-specific CD8+ T-cell responses that were enhanced by depletion of regulatory T (Treg) cells by either anti-CD25 or cyclophosphamide treatment. Antitumor activity of LM further depended on natural killer (NK) cell activation but was inhibited by presence of a subset of NK T cells. These results show the utility of LM in the treatment of hepatic metastases even in the absence of vaccine administration and further suggest that blockade of Treg cells and NK T cells will enhance antitumor activity. [Cancer Res 2007;67(20):10058–66]
Data from Fhit-Deficient Hematopoietic Stem Cells Survive Hydroquinone Exposure Carrying Precancerous Changes
Authors: Ishii Hideshi , Mimori Koshi , Ishikawa Kazuhiro , Okumura Hiroshi , Pichiorri Flavia , Druck Teresa , Inoue Hiroshi , Vecchione Andrea , Saito Toshiyuki , Mori Masaki , Huebner Kay
Published: March 2023

Abstract
The fragile FHIT gene is among the first targets of DNA damage in preneoplastic lesions, and recent studies have shown that Fhit protein is involved in surveillance of genome integrity and checkpoint response after genotoxin exposure. We now find that Fhit-deficient hematopoietic cells, exposed to the genotoxin hydroquinone, are resistant to the suppression of stem cell in vitro colony formation observed with wild-type (Wt) hematopoietic cells. In vivo–transplanted, hydroquinone-exposed, Fhit-deficient bone marrow cells also escaped the bone marrow suppression exhibited by Wt-transplanted bone marrow. Comparative immunohistochemical analyses of bone marrow transplants showed relative absence of Bax in Fhit-deficient bone marrow, suggesting insensitivity to apoptosis; assessment of DNA damage showed that occurrence of the oxidized base 8-hydroxyguanosine, a marker of DNA damage, was also reduced in Fhit-deficient bone marrow, as was production of intracellular reactive oxygen species. Treatment with the antioxidant N-acetyl-l-cysteine relieved hydroquinone-induced suppression of colony formation by Wt hematopoietic cells, suggesting that the decreased oxidative damage to Fhit-deficient cells, relative to Wt hematopoietic cells, accounts for the survival advantage of Fhit-deficient bone marrow. Homology-dependent recombination repair predominated in Fhit-deficient cells, although not error-free repair, as indicated by a higher incidence of 6-thioguanine–resistant colonies. Tissues of hydroquinone-exposed Fhit-deficient bone marrow–transplanted mice exhibited preneoplastic alterations, including accumulation of histone H2AX-positive DNA damage. The results indicate that reduced oxidative stress, coupled with efficient but not error-free DNA damage repair, allows unscheduled long-term survival of genotoxin-exposed Fhit-deficient hematopoietic stem cells carrying deleterious mutations. [Cancer Res 2008;68(10):3662–70]
Data from Human T-Cell Leukemia Virus I Tax Protein Sensitizes p53-Mutant Cells to DNA Damage
Authors: Mihaylova Valia T. , Green Allison M. , Khurgel Moshe , Semmes Oliver J. , Kupfer Gary M.
Published: March 2023

Abstract
Mutations in p53 are a common cause of resistance of cancers to standard chemotherapy and, thus, treatment failure. Reports have shown that Tax, a human T-cell leukemia virus type I encoded protein that has been associated with genomic instability and perturbation of transcription and cell cycle, sensitizes HeLa cells to UV treatment. The extent to which Tax can sensitize cells and the mechanism by which it exerts its effect are unknown. In this study, we show that Tax sensitizes p53-mutant cells to a broad range of DNA-damaging agents, including mitomycin C, a bifunctional alkylator, etoposide, a topoisomerase II drug, and UV light, but not ionizing radiation, a double-strand break agent, or vinblastine, a tubulin poison. Tax caused hypersensitivity in all p53-deleted cell lines and several, but not all, mutant-expressed p53–containing cell lines, while unexpectedly being protective in p53 wild-type (wt) cells. The effect observed in p53-deleted lines could be reversed for this by transfection of wt p53. We also show that Tax activates a p53-independent proapoptotic program through decreased expression of the retinoblastoma protein and subsequent increased E2F1 expression. The expression of several proapoptotic proteins was also induced by Tax, including Puma and Noxa, culminating in a substantial increase in Bax dimerization. Our results show that Tax can sensitize p53-mutant cells to DNA damage while protecting p53 wt cells, a side benefit that might result in reduced toxicity in normal cells. Such studies hold the promise of a novel adjunctive therapy that could make cancer chemotherapy more effective. [Cancer Res 2008;68(12):4843–52]
Data from Gene Expression Profiling of Breast, Prostate, and Glioma Cells following Single versus Fractionated Doses of Radiation
Authors: Tsai Mong-Hsun , Cook John A. , Chandramouli Gadisetti V.R. , DeGraff William , Yan Hailing , Zhao Shuping , Coleman C. Norman , Mitchell James B. , Chuang Eric Y.
Published: March 2023

Abstract
Studies were conducted to determine whether gene expression profiles following a single dose of radiation would yield equivalent profiles following fractionated radiation in different tumor cell lines. MCF7 (breast), DU145 (prostate), and SF539 (gliosarcoma) cells were exposed to a total radiation dose of 10 Gy administered as a single dose (SD) or by daily multifractions (MF) of 5 × 2 Gy. Following radiation treatment, mRNA was isolated at 1, 4, 10, and 24 h and processed for cDNA microarray analysis. To determine the influence of the tumor microenvironment on gene expression, one cell type (DU145) was evaluated growing as a solid tumor in athymic nude mice for both radiation protocols. Unsupervised hierarchical cluster map analysis showed significant differences in gene expression profiles between SD and MF treatments for cells treated in vitro, with MF yielding a more robust induction compared with SD. Several genes were uniquely up-regulated by MF treatment, including multiple IFN-related genes (STAT1, G1P2, OAS1, OAS3, G1P3, IFITM1) and TGF-β–associated genes (EGR1, VEGF, THBS1, and TGFB2). DU145 cells grown in vivo exhibited a completely different set of genes induced by both SD and MF compared with the same cells exposed in vitro. The results of the study clearly show distinct differences in the molecular response of cells between SD and MF radiation exposures and show that the tumor microenvironment can significantly influence the pattern of gene expression after radiation exposures. [Cancer Res 2007;67(8):3845–52]
Data from Cortactin Is an Essential Regulator of Matrix Metalloproteinase Secretion and Extracellular Matrix Degradation in Invadopodia
Authors: Clark Emily S. , Whigham Amy S. , Yarbrough Wendell G. , Weaver Alissa M.
Published: March 2023

Abstract
Invadopodia are branched actin-rich structures associated with extracellular matrix (ECM) degradation that collectively form the invasive machinery of aggressive cancer cells. Cortactin is a prominent component and a specific marker of invadopodia. Amplification of cortactin is associated with poor prognosis in head and neck squamous cell carcinomas (HNSCC), possibly because of its activity in invadopodia. Although the role of cortactin in invadopodia has been attributed to signaling and actin assembly, it is incompletely understood. We made HNSCC cells deficient in cortactin by RNA interference knockdown methods. In these cortactin knockdown cells, invadopodia were reduced in number and lost their ability to degrade ECM. In the reverse experiment, overexpression of cortactin dramatically increased ECM degradation, far above and beyond the effect on formation of actin/Arp3–positive invadopodia puncta. Secretion of matrix metalloproteinases (MMP) MMP-2 and MMP-9, as well as plasma membrane delivery of MT1-MMP correlated closely with cortactin expression levels. MMP inhibitor treatment of control cells mimicked the cortactin knockdown phenotype, with abolished ECM degradation and fewer invadopodia, suggesting a positive feedback loop in which degradation products from MMP activity promote new invadopodia formation. Collectively, these data suggest that a major role of cortactin in invadopodia is to regulate the secretion of MMPs and point to a novel mechanism coupling dynamic actin assembly to the secretory machinery, producing enhanced ECM degradation and invasiveness. Furthermore, these data provide a possible explanation for the observed association between cortactin overexpression and enhanced invasiveness and poor prognosis in HNSCC patients. [Cancer Res 2007;67(9):4227–35]
Data from Batracylin (NSC 320846), a Dual Inhibitor of DNA Topoisomerases I and II Induces Histone γ-H2AX as a Biomarker of DNA Damage
Authors: Rao V. Ashutosh , Agama Keli , Holbeck Susan , Pommier Yves
Published: March 2023

Abstract
Batracylin (8-aminoisoindolo [1,2-b]quinazolin-10(12H)-one; NSC320846) is an investigational clinical anticancer agent. Previous animal studies showed activity against solid tumors and Adriamycin-resistant leukemia. We initially sought to test the proposed Top2-mediated DNA cleavage activity of batracylin and identify potential biomarkers for activity. COMPARE analysis in the NCI-60 cell lines showed batracylin activity to be most closely related to the class of Top2 inhibitors. The 50% growth inhibition (GI50) value for batracylin in HT29 colon carcinoma cells was 10 μmol/L. DNA-protein cross-links, consistent with Top2 targeting, were measured by alkaline elution. DNA single-strand breaks were also detected and found to be protein associated. However, only a weak induction of DNA double-strand breaks was observed. Because batracylin induced almost exclusively DNA single-strand breaks, we tested batracylin as a Top1 inhibitor. Batracylin exhibited both Top1- and Top2α/β-mediated DNA cleavage in vitro and in cells. The phosphorylation of histone (γ-H2AX) was tested to measure the extent of DNA damage. Kinetics of γ-H2AX “foci” showed early activation with low μmol/L concentrations, thus presenting a useful early biomarker of DNA damage. The half-life of γ-H2AX signal reversal after drug removal was consistent with reversal of DNA-protein cross-links. The persistence of the DNA-protein complexes induced by batracylin was markedly longer than by etoposide or camptothecin. The phosphorylated DNA damage–responsive kinase, ataxia telangiectasia mutated, was also found activated at sites of γ-H2AX. The cell cycle checkpoint kinase, Chk2, was only weakly phosphorylated. Thus, batracylin is a dual Top1 and Top2 inhibitor and γ-H2AX could be considered a biomarker in the ongoing clinical trials. [Cancer Res 2007;67(20):9971–9]
Data from The Nuclear Matrix Protein, NRP/B, Enhances Nrf2-Mediated Oxidative Stress Responses in Breast Cancer Cells
Authors: Seng Seyha , Avraham Hava Karsenty , Jiang Shuxian , Yang Suping , Sekine Masayuki , Kimelman Noam , Li Huchun , Avraham Shalom
Published: March 2023

Abstract
The transcription factor NF-E2–related factor 2 (Nrf2) translocates into the nucleus and activates phase II genes encoding detoxification enzymes and antioxidant proteins, resulting in the protection of cells from oxidative insults. However, the involvement of Nrf2-mediated oxidative stress responses in breast cancer cells is largely unknown. Notably, during our study of the Nrf2 pathway in breast cancer cells, we observed that the nuclear matrix protein NRP/B was expressed and colocalized with Nrf2 in these cells, suggesting that NRP/B is involved in Nrf2-mediated oxidative stress responses. The expression level of NRP/B was variable in different breast cancer cells and breast cancer tissues, and was found to be localized in the nucleus. NRP/B expression was increased after exposure to the oxidative stress agent, hydrogen peroxide (H2O2), particularly in the highly aggressive MDA-MB-231 breast cancer cells. Association of NRP/B with Nrf2 in vitro and in vivo was observed in MDA-MB-231 breast cancer cells, and this association was up-regulated upon exposure to H2O2, but not to sodium nitroprusside, SIN-1, and DETA-NO. NRP/B also enhanced Nrf2-mediated NAD(P)H:quinine oxidoreductase 1 promoter activity. Thus, this study reveals that NRP/B enhances oxidative stress responses in breast cancer cells via the Nrf2 pathway, identifying a novel role of nuclear matrix protein(s) in oxidative stress responses. [Cancer Res 2007;67(18):8596–604]
Data from Cancer Immunotherapy Using Irradiated Tumor Cells Secreting Heat Shock Protein 70
Authors: Chang Chih-Long , Tsai Ya-Chea , He Liangmei , Wu T.-C. , Hung Chien-Fu
Published: March 2023

Abstract
Ovarian cancer is responsible for the highest mortality rate among patients with gynecologic malignancies. Therefore, there is an emerging need for innovative therapies for the control of advanced ovarian cancer. Immunotherapy has emerged as a potentially plausible approach for the control of ovarian cancer. In the current study, we have generated heat shock protein 70 (Hsp70)-secreting murine ovarian cancer cells that express luciferase (MOSEC/luc). Hsp70 has been shown to target and concentrate antigenic peptides in dendritic cells and is also able to activate dendritic cells. We characterized the antigen-specific immune response and the antitumor effect of the MOSEC/luc cells expressing Hsp70 using noninvasive luminescence images to measure the amount of ovarian tumors in the peritoneal cavity of mice. We found that mice challenged with MOSEC/luc cells expressing Hsp70 generate significant antigen-specific CD8+ T-cell immune responses. Furthermore, we also found that mice vaccinated with irradiated MOSEC/luc cells expressing Hsp70 generate significant therapeutic effect against MOSEC/luc cells. In addition, we have shown that CD8+, natural killer, and CD4+ cells are important for protective antitumor effect generated by irradiated tumor cell–based vaccines expressing Hsp70. Moreover, we also found that CD40 receptor is most important, followed by Toll-like receptor 4 receptor, for inhibiting in vivo tumor growth of the viable MOSEC/luc expressing Hsp70. Thus, the use of Hsp70-secreting ovarian tumor cells represents a potentially effective therapy for the control of lethal ovarian cancer. [Cancer Res 2007;67(20):10047–57]
Data from Association of Genetic Variation in the Transforming Growth Factor β-1 Gene with Serum Levels and Risk of Colorectal Neoplasia
Authors: Saltzman Barbara S. , Yamamoto Jennifer F. , Decker Robert , Yokochi Lance , Theriault Andre G. , Vogt Thomas M. , Le Marchand Loïc
Published: March 2023

Abstract
In the normal intestinal epithelium transforming growth factor β-1 (TGFβ-1) acts as a growth inhibitor, but in malignant cells it may act as a tumor promoter. However, only limited information is available on genetic variation in the TGFB1 gene and its relationship to circulating levels and risk of colorectal cancer. To characterize associations of genetic variation [tagging single-nucleotide polymorphisms (tagSNP) and haplotypes with frequency >0.05] at the TGFB1 locus with circulating TGFβ-1 and risk of colorectal neoplasia, we conducted two case-control studies (including 271 colorectal adenoma cases and 544 controls, and 535 colorectal adenocarcinoma cases and 656 controls) among Japanese Americans, Caucasians, and Native Hawaiians in Hawaii. Serum TGFβ-1 was measured by sandwich ELISA among the subjects of the first study. The variant A allele for tagSNP rs6957 was associated with higher serum TGFβ-1 [means (in ng/mL) and 95% confidence interval (95% CI) for AA or AG, 32.6 (30.6–34.7); GG, 29.0 (25.1–32.9); Pdifference = 0.05] after adjusting for age and other factors. Homozygous carriers of the variant G allele for tagSNP rs11466345 had a statistically significantly lower risk of adenocarcinoma [AG versus AA: odds ratio (OR), 0.9 (95% CI, 0.7–1.2); GG versus AA: OR, 0.4 (95% CI, 0.2–0.7); Ptrend = 0.01]. The haplotype carrying both variants was also statistically significantly associated with a reduced risk of adenocarcinoma (OR, 0.3; 95% CI, 0.1–0.8). Although not statistically significant, the direction and magnitude of the corresponding ORs were similar for adenoma. These results suggest that a haplotype containing SNP rs11466345 at the 3′ end of TGFB1 is associated with genetic susceptibility to colorectal neoplasia. [Cancer Res 2008;68(4):1236–44]
Data from Role of the Aggresome Pathway in Cancer: Targeting Histone Deacetylase 6–Dependent Protein Degradation
Authors: Rodriguez-Gonzalez Agustin , Lin Tara , Ikeda Alan K. , Simms-Waldrip Tiffany , Fu Cecilia , Sakamoto Kathleen M.
Published: March 2023

Abstract
Misfolded or aggregated proteins have two fates: they are either refolded with the help of chaperones or degraded by the proteasome. Cells also have an alternative pathway that involves intracellular “storage bins” for misfolded intracellular proteins known as aggresomes. Aggresomes recruit motor proteins that transport misfolded or aggregated proteins to chaperones and proteasomes for subsequent destruction. There is emerging evidence that inhibiting the aggresome pathway leads to accumulation of misfolded proteins and apoptosis in tumor cells through autophagy. We discuss the role of aggresomes in cancer and the potential to target this pathway for therapy. [Cancer Res 2008;68(8):2557–60]