bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Sleeping Beauty–Mediated Somatic Mutagenesis Implicates CSF1 in the Formation of High-Grade Astrocytomas
Authors: Bender Aaron M. , Collier Lara S. , Rodriguez Fausto J. , Tieu Christina , Larson Jon D. , Halder Chandralekha , Mahlum Eric , Kollmeyer Thomas M. , Akagi Keiko , Sarkar Gobinda , Largaespada David A. , Jenkins Robert B.
Published: March 2024

Abstract
The Sleeping Beauty (SB) transposon system has been used as an insertional mutagenesis tool to identify novel cancer genes. To identify glioma-associated genes, we evaluated tumor formation in the brain tissue from 117 transgenic mice that had undergone constitutive SB-mediated transposition. Upon analysis, 21 samples (18%) contained neoplastic tissue with features of high-grade astrocytomas. These tumors expressed glial markers and were histologically similar to human glioma. Genomic DNA from SB-induced astrocytoma tissue was extracted and transposon insertion sites were identified. Insertions in the growth factor gene Csf1 were found in 13 of the 21 tumors (62%), clustered in introns 5 and 8. Using reverse transcription-PCR, we documented increased Csf1 RNAs in tumor versus adjacent normal tissue, with the identification of transposon-terminated Csf1 mRNAs in astrocytomas with SB insertions in intron 8. Analysis of human glioblastomas revealed increased levels of Csf1 RNA and protein. Together, these results indicate that SB-insertional mutagenesis can identify high-grade astrocytoma-associated genes and they imply an important role for CSF1 in the development of these tumors. Cancer Res; 70(9); 3557–65. ©2010 AACR.
Data from Blockade of CCN6 (WISP3) Activates Growth Factor–Independent Survival and Resistance to Anoikis in Human Mammary Epithelial Cells
Authors: Huang Wei , Gonzalez Maria E. , Toy Kathy A. , Banerjee Mousumi , Kleer Celina G.
Published: March 2024

Abstract
CCN6 is a secreted cysteine-rich matricellular protein (36.9 kDa) that exerts growth-inhibitory functions in breast cancer. Reduction or loss of CCN6 protein has been reported in invasive carcinomas of the breast with lymph node metastasis and in inflammatory breast cancer. However, the mechanism by which CCN6 loss promotes breast cancer growth remains to be defined. In the present study, we developed lentiviral-mediated short hairpin RNA CCN6 knockdown (KD) in nontumorigenic mammary epithelial cells MCF10A and HME. We discovered that CCN6 KD protects mammary epithelial cells from apoptosis and activates growth factor–independent survival. In the absence of exogenous growth factors, CCN6 KD was able to promote growth under anchorage-independent conditions and triggered resistance to detachment-induced cell death (anoikis). On serum starvation, CCN6 KD was sufficient for activation of the phosphatidylinositol 3-kinase (PI3K)/Akt pathway. Growth factor–independent cell survival was stunted in CCN6 KD cells when treated with either human recombinant CCN6 protein or the PI3K inhibitor LY294002. Targeted inhibition of Akt isoforms revealed that the survival advantage rendered by CCN6 KD requires specific activation of Akt-1. The relevance of our studies to human breast cancer is highlighted by the finding that low CCN6 protein levels are associated with upregulated expression of phospho-Akt-1 (Ser473) in 21% of invasive breast carcinomas. These results enable us to pinpoint one mechanism by which CCN6 controls survival of breast cells mediated by the PI3K/Akt-1 pathway. Cancer Res; 70(8); 3340–50. ©2010 AACR.
Data from Tissue-Specific Pathways for Estrogen Regulation of Ovarian Cancer Growth and Metastasis
Authors: Spillman Monique A. , Manning Nicole G. , Dye Wendy W. , Sartorius Carol A. , Post Miriam D. , Harrell Joshua Chuck , Jacobsen Britta M. , Horwitz Kathryn B.
Published: March 2024

Abstract
Menopausal estrogen (E2) replacement therapy increases the risk of estrogen receptor (ER)–positive epithelial ovarian cancers (EOC). Whether E2 is tumorigenic or promotes expansion of undiagnosed preexisting disease is unknown. To determine E2 effects on tumor promotion, we developed an intraperitoneal mouse xenograft model using ZsGreen fluorescent ER− 2008 and ER+ PEO4 human EOC cells. Tumor growth was quantified by in vivo fluorescent imaging. In ER+ tumors, E2 significantly increased size, induced progesterone receptors, and promoted lymph node metastasis, confirming that ERs are functional and foster aggressiveness. Laser-captured human EOC cells from ER− and ER+ xenografted tumors were profiled for expression of E2-regulated genes. Three classes of E2-regulated EOC genes were defined, but <10% were shared with E2-regulated breast cancer genes. Because breast cancer selective ER modulators (SERM) are therapeutically ineffective in EOC, we suggest that our EOC-specific E2-regulated genes can assist pharmacologic discovery of ovarian-targeted SERM. Cancer Res; 70(21); 8927–36. ©2010 AACR.
Data from PTPH1 Dephosphorylates and Cooperates with p38γ MAPK to Increase Ras Oncogenesis through PDZ-Mediated Interaction
Authors: Hou Song-Wang , Zhi Hui-Ying , Pohl Nicole , Loesch Mathew , Qi Xiao-Mei , Li Rong-Shan , Basir Zainab , Chen Guan
Published: March 2024

Abstract
Protein phosphatases are believed to coordinate with kinases to execute biological functions, but examples of such integrated activities, however, are still missing. In this report, we have identified protein tyrosine phosphatase H1 (PTPH1) as a specific phosphatase for p38γ mitogen-activated protein kinase (MAPK) and shown their cooperative oncogenic activity through direct binding. p38γ, a Ras effector known to act independent of its phosphorylation, was first shown to require its unique PDZ-binding motif to increase Ras transformation. Yeast two-hybrid screening and in vitro and in vivo analyses further identified PTPH1 as a specific p38γ phosphatase through PDZ-mediated binding. Additional experiments showed that PTPH1 itself plays a role in Ras-dependent malignant growth in vitro and/or in mice by a mechanism depending on its p38γ-binding activity. Moreover, Ras increases both p38γ and PTPH1 protein expression and there is a coupling of increased p38γ and PTPH1 protein expression in primary colon cancer tissues. These results reveal a coordinative oncogenic activity of a MAPK with its specific phosphatase and suggest that PDZ-mediated p38γ/PTPH1 complex may be a novel target for Ras-dependent malignancies. Cancer Res; 70(7); 2901–10
Data from Pancreatic Stellate Cells Radioprotect Pancreatic Cancer Cells through β1-Integrin Signaling
Authors: Mantoni Tine S. , Lunardi Serena , Al-Assar Osama , Masamune Atsushi , Brunner Thomas B.
Published: March 2024

Abstract
Pancreatic ductal adenocarcinoma (PDAC) is characterized by a strong desmoplastic reaction where the stromal compartment often accounts for more than half of the tumor volume. Pancreatic stellate cells (PSC) are a central mediator of desmoplasia. There is increasing evidence that desmoplasia is contributing to the poor therapeutic response of PDAC. We show that PSCs promote radioprotection and stimulate proliferation in pancreatic cancer cells (PCC) in direct coculture. Our in vivo studies show PSC-dependent radioprotection in response to a single dose and to fractionated radiation. Abrogating β1-integrin signaling abolishes the PSC-mediated radioprotection in PCCs. Furthermore, this effect is independent of PI3K (phosphoinositide 3-kinase) but dependent on FAK. Taken together, we show for the first time that PSCs promote radioprotection of PCCs in a β1-integrin–dependent manner. Cancer Res; 71(10); 3453–8. ©2011 AACR.
Data from Peptides and Aptamers Targeting HSP70: A Novel Approach for Anticancer Chemotherapy
Authors: Rérole Anne-Laure , Gobbo Jessica , De Thonel Aurelie , Schmitt Elise , Pais de Barros Jean Paul , Hammann Arlette , Lanneau David , Fourmaux Eric , Deminov Oleg , Micheau Olivier , Lagrost Laurent , Colas Pierre , Kroemer Guido , Garrido Carmen
Published: March 2024

Abstract
The inhibition of heat shock protein 70 (HSP70) is an emerging strategy in cancer therapy. Unfortunately, no specific inhibitors are clinically available. By yeast two-hybrid screening, we have identified multiple peptide aptamers that bind HSP70. When expressed in human tumor cells, two among these peptide aptamers—A8 and A17—which bind to the peptide-binding and the ATP-binding domains of HSP70, respectively, specifically inhibited the chaperone activity, thereby increasing the cells' sensitivity to apoptosis induced by anticancer drugs. The 13-amino acid peptide from the variable region of A17 (called P17) retained the ability to specifically inhibit HSP70 and induced the regression of subcutaneous tumors in vivo after local or systemic injection. This antitumor effect was associated with an important recruitment of macrophages and T lymphocytes into the tumor bed. Altogether, these data indicate that peptide aptamers or peptides that target HSP70 may be considered as novel lead compounds for cancer therapy. Cancer Res; 71(2); 484–95. ©2011 AACR.
Data from Induction of Cancer Cell Death by Self-assembling Nanostructures Incorporating a Cytotoxic Peptide
Authors: Standley Stephany M. , Toft Daniel J. , Cheng Hao , Soukasene Stephen , Chen Jing , Raja Srikumar M. , Band Vimla , Band Hamid , Cryns Vincent L. , Stupp Samuel I.
Published: March 2024

Abstract
Nanotechnology offers novel delivery vehicles for cancer therapeutics. Potential advantages of nanoscale platforms include improved pharmacokinetics, encapsulation of cytotoxic agents, enhanced accumulation of therapeutics in the tumor microenvironment, and improved therapeutic structures and bioactivity. Here, we report the design of a novel amphiphilic molecule that self-assembles into nanostructures for intracellular delivery of cytotoxic peptides. Specifically, a cationic α-helical (KLAKLAK)2 peptide that is known to induce cancer cell death by membrane disruption was integrated into a peptide amphiphile (PA) that self-assembles into bioactive, cylindrical nanofibers. PAs are composed of a hydrophobic alkyl tail, a β-sheet forming peptide, and a bioactive peptide that is displayed on the surface of the nanofiber after self-assembly. PA nanostructures that included (KLAKLAK)2 were readily internalized by breast cancer cells, in contrast to the (KLAKLAK)2 peptide that on its own was not cell permeable. (KLAKLAK)2 nanostructures, but not the peptides alone, also induced breast cancer cell death by caspase-independent and Bax/Bak–independent mechanisms associated with membrane disruption. Significantly, (KLAKLAK)2 nanostructures induced cell death more robustly in transformed breast epithelial cells than in untransformed cells, suggesting a degree of tumor selectivity. Our results provide proof-of-principle that self-assembling PAs can be rationally designed to generate nanostructures that can efficiently deliver cytotoxic peptides to cancer cells. Cancer Res; 70(8); 3020–6. ©2010 AACR.
Data from MicroRNA-375 Is Downregulated in Gastric Carcinomas and Regulates Cell Survival by Targeting PDK1 and 14-3-3ζ
Authors: Tsukamoto Yoshiyuki , Nakada Chisato , Noguchi Tsuyoshi , Tanigawa Masato , Nguyen Lam Tung , Uchida Tomohisa , Hijiya Naoki , Matsuura Keiko , Fujioka Toshio , Seto Masao , Moriyama Masatsugu
Published: March 2024

Abstract
We investigated expression profiles of microRNA (miRNA) in gastric carcinomas by use of a miRNA microarray platform covering a total of 470 human miRNAs. We identified 39 differentially expressed miRNAs in gastric carcinoma, of which six were significantly downregulated and the other 33 were upregulated. We found that miRNA-375 (miR-375) was the most downregulated and that its ectopic expression in gastric carcinoma cells markedly reduced cell viability via the caspase-mediated apoptosis pathway. Interestingly, we found that expression of miR-375 inhibited expression of PDK1, which is a direct target of miR-375, followed by suppression of Akt phosphorylation. Further analysis by gene expression microarray revealed that 14-3-3ζ, a potent antiapoptotic gene, was significantly downregulated at both the mRNA and protein levels in cells transfected with miR-375. The activity of a luciferase reporter containing the miR-375 binding sequence at the 3′ untranslated region (UTR) of 14-3-3ζ mRNA was repressed by the ectopic expression of miR-375, suggesting that miR-375 targets the 3′ UTR of 14-3-3ζ. In addition, knockdown of either PDK1 or 14-3-3ζ in gastric carcinoma cells induced caspase activation, which was also observed in miR-375–transfected cells, suggesting that miR-375 may exert its proapoptotic function, at least in part, through the downregulation of PDK1 and 14-3-3ζ. Taken together, we propose that miR-375 is a candidate tumor suppressor miRNA in gastric carcinoma. Cancer Res; 70(6); 2339–49
Data from The Neurofibromatosis Type 1 Tumor Suppressor Controls Cell Growth by Regulating Signal Transducer and Activator of Transcription-3 Activity In vitro and In vivo
Authors: Banerjee Sutapa , Byrd Jonathan N. , Gianino Scott M. , Harpstrite Scott E. , Rodriguez Fausto J. , Tuskan Robert G. , Reilly Karlyne M. , Piwnica-Worms David R. , Gutmann David H.
Published: March 2024

Abstract
Neurofibromatosis type 1 (NF1) is a common cancer predisposition syndrome in which affected individuals develop benign and malignant nerve tumors. The NF1 gene product neurofibromin negatively regulates Ras and mammalian target of rapamycin (mTOR) signaling, prompting clinical trials to evaluate the ability of Ras and mTOR pathway inhibitors to arrest NF1-associated tumor growth. To discover other downstream targets of neurofibromin, we performed an unbiased cell-based high-throughput chemical library screen using NF1-deficient malignant peripheral nerve sheath tumor (MPNST) cells. We identified the natural product, cucurbitacin-I (JSI-124), which inhibited NF1-deficient cell growth by inducing apoptosis. We further showed that signal transducer and activator of transcription-3 (STAT3), the target of cucurbitacin-I inhibition, was hyperactivated in NF1-deficient primary astrocytes and neural stem cells, mouse glioma cells, and human MPNST cells through Ser727 phosphorylation, leading to increased cyclin D1 expression. STAT3 was regulated in NF1-deficient cells of murine and human origin in a TORC1- and Rac1-dependent manner. Finally, cucurbitacin-I inhibited the growth of NF1-deficient MPNST cells in vivo. In summary, we used a chemical genetics approach to reveal STAT3 as a novel neurofibromin/mTOR pathway signaling molecule, define its action and regulation, and establish STAT3 as a tractable target for future NF1-associated cancer therapy studies. Cancer Res; 70(4); 1356–66
Data from Serologic Markers of Effective Tumor Immunity against Chronic Lymphocytic Leukemia Include Nonmutated B-Cell Antigens
Authors: Marina Ovidiu , Hainz Ursula , Biernacki Melinda A. , Zhang Wandi , Cai Ann , Duke-Cohan Jonathan S. , Liu Fenglong , Brusic Vladimir , Neuberg Donna , Kutok Jeffery L. , Alyea Edwin P. , Canning Christine M. , Soiffer Robert J. , Ritz Jerome , Wu Catherine J.
Published: March 2024

Abstract
Patients with chronic lymphocytic leukemia (CLL) who relapse after allogeneic transplant may achieve durable remission following donor lymphocyte infusion (DLI), showing the potency of donor-derived immunity in eradicating tumors. We sought to elucidate the antigenic basis of the effective graft-versus-leukemia (GvL) responses associated with DLI for the treatment of CLL by analyzing the specificity of plasma antibody responses developing in two DLI-treated patients who achieved long-term remission without graft-versus-host disease. By probing high-density protein microarrays with patient plasma, we discovered 35 predominantly intracellular antigens that elicited high-titer antibody reactivity greater in post-DLI than in pre-DLI plasma. Three antigens—C6orf130, MDS032, and ZFYVE19—were identified by both patients. Along with additional candidate antigens DAPK3, SERBP1, and OGFOD1, these proteins showed higher transcript and protein expression in B cells and CLL cells compared with normal peripheral blood mononuclear cells. DAPK3 and the shared antigens do not represent minor histocompatibility antigens, as their sequences are identical in both donor and tumor. Although ZFYVE19, DAPK3, and OGFOD1 elicited minimal antibody reactivity in 12 normal subjects and 12 chemotherapy-treated CLL patients, 5 of 12 CLL patients with clinical GvL responses were serologically reactive to these antigens. Moreover, antibody reactivity against these antigens was temporally correlated with clinical disease regression. These B-cell antigens represent promising biomarkers of effective anti-CLL immunity. Cancer Res; 70(4); 1344–55
Data from Definition of Ubiquitination Modulator COP1 as a Novel Therapeutic Target in Human Hepatocellular Carcinoma
Authors: Lee Yun-Han , Andersen Jesper B. , Song Ho-Taek , Judge Adam D. , Seo Daekwan , Ishikawa Tsuyoshi , Marquardt Jens U. , Kitade Mitsuteru , Durkin Marian E. , Raggi Chiara , Woo Hyun Goo , Conner Elizabeth A. , Avital Itzhak , MacLachlan Ian , Factor Valentina M. , Thorgeirsson Snorri S.
Published: March 2024

Abstract
The development of targeted therapeutics for hepatocellular carcinoma (HCC) remains a major challenge. The ubiquitination modulator COP1 regulates p53 activity by ubiquitination and it is frequently overexpressed in human HCC. In this study, we tested the hypothesis that COP1 blockade by short interfering RNA (siRNA)–mediated inhibition could affect the course of HCC progression. The COP1 isoform COP1-1 was selected as the most effective target for siRNAs in terms of growth inhibition and apoptotic induction in several HCC cell lines. Growth inhibition occurred in HCC cells that retained wild-type p53 or expressed mutant p53 (Y220C or R249S), whereas p53-null Hep3B cells were resistant. Microarray expression analysis revealed that the antiproliferative effects of COP1 blockade were driven by a common subset of molecular alterations including a p53-associated functional network. In an orthotopic mouse xenograft model of HCC, systemic delivery of a modified COP1 siRNA by stable nucleic acid–lipid particles suppressed neoplastic growth in liver without unwanted immune responses. Our findings offer a first proof of principle that COP1 can be a promising target for systemic therapy of HCC. Cancer Res; 70(21); 8264–9. ©2010 AACR.
Data from Genetic Polymorphisms in Vitamin D Receptor VDR/RXRA Influence the Likelihood of Colon Adenoma Recurrence
Authors: Egan Jan B. , Thompson Patricia A. , Ashbeck Erin L. , Conti David V. , Duggan David , Hibler Elizabeth , Jurutka Peter W. , LeRoy Elizabeth C. , Martínez María Elena , Mount David , Jacobs Elizabeth T.
Published: March 2024

Abstract
Low circulating levels of vitamin D affect colorectal cancer risk. The biological actions of the hormonal form of vitamin D, 1,25(OH)2D3, are mediated by the vitamin D receptor (VDR), which heterodimerizes with retinoid X receptors (RXR). Using a single nucleotide polymorphism (SNP) tagging approach, we assessed the association between genetic variations in RXRA and VDR and odds of recurrent (metachronous) colorectal neoplasia in a pooled population of two studies. A total of 32 tag SNPs in RXRA and 42 in VDR were analyzed in 1,439 participants. A gene-level association was observed for RXRA and any (P = 0.04) or proximal (P = 0.03) metachronous neoplasia. No gene-level associations were observed for VDR, nor was any single SNP in VDR related to any metachronous adenoma after correction for multiple comparisons. In contrast, the association between RXRA SNP rs7861779 and proximal metachronous neoplasia was of borderline statistical significance [odds ratio (OR), 0.68; 95% confidence interval (95% CI), 0.53-0.86; unadjusted P = 0.001; adjusted P = 0.06], including when observed independently in each individual study. Haplotypes within linkage blocks of RXRA support an ∼30% reduction in odds of metachronous neoplasia arising in the proximal colon among carriers of specific haplotypes, which was strongest (ORproximal, 0.67; 95% CI, 0.52–0.86) for carriers of a CGGGCA haplotype (rs1805352, rs3132297, rs3132296, rs3118529, rs3118536, and rs7861779). Our results indicate that allelic variation in RXRA affects metachronous colorectal neoplasia, perhaps of particular importance in the development of proximal lesions. Cancer Res; 70(4); 1496–504
Data from Sustained Small Interfering RNA Delivery by Mesoporous Silicon Particles
Authors: Tanaka Takemi , Mangala Lingegowda S. , Vivas-Mejia Pablo E. , Nieves-Alicea René , Mann Aman P. , Mora Edna , Han Hee-Dong , Shahzad Mian M.K. , Liu Xuewu , Bhavane Rohan , Gu Jianhua , Fakhoury Jean R. , Chiappini Ciro , Lu Chunhua , Matsuo Koji , Godin Biana , Stone Rebecca L. , Nick Alpa M. , Lopez-Berestein Gabriel , Sood Anil K. , Ferrari Mauro
Published: March 2024

Abstract
RNA interference (RNAi) is a powerful approach for silencing genes associated with a variety of pathologic conditions; however, in vivo RNAi delivery has remained a major challenge due to lack of safe, efficient, and sustained systemic delivery. Here, we report on a novel approach to overcome these limitations using a multistage vector composed of mesoporous silicon particles (stage 1 microparticles, S1MP) loaded with neutral nanoliposomes (dioleoyl phosphatidylcholine, DOPC) containing small interfering RNA (siRNA) targeted against the EphA2 oncoprotein, which is overexpressed in most cancers, including ovarian. Our delivery methods resulted in sustained EphA2 gene silencing for at least 3 weeks in two independent orthotopic mouse models of ovarian cancer following a single i.v. administration of S1MP loaded with EphA2-siRNA-DOPC. Furthermore, a single administration of S1MP loaded with-EphA2-siRNA-DOPC substantially reduced tumor burden, angiogenesis, and cell proliferation compared with a noncoding control siRNA alone (SKOV3ip1, 54%; HeyA8, 57%), with no significant changes in serum chemistries or in proinflammatory cytokines. In summary, we have provided the first in vivo therapeutic validation of a novel, multistage siRNA delivery system for sustained gene silencing with broad applicability to pathologies beyond ovarian neoplasms. Cancer Res; 70(9); 3687–96. ©2010 AACR.
Data from Activation and Involvement of Ral GTPases in Colorectal Cancer
Authors: Martin Timothy D. , Samuel Jonathan C. , Routh Elizabeth D. , Der Channing J. , Yeh Jen Jen
Published: March 2024

Abstract
Current approaches to block KRAS oncogene function focus on inhibition of K-Ras downstream effector signaling. We evaluated the antitumor activity of selumetinib (AZD6244, ARRY-142886), a potent and selective MEK1/2 inhibitor, on a panel of colorectal carcinoma (CRC) cells and found no inhibition of KRAS mutant CRC cell anchorage-independent growth. Although AKT activity was elevated in KRAS mutant cells, and PI3K inhibition did impair the growth of MEK inhibitor-insensitive CRC cell lines, concurrent treatment with selumetinib did not provide additional antitumor activity. Therefore, we speculated that inhibition of the Ral guanine exchange factor (RalGEF) effector pathway may be a more effective approach for blocking CRC growth. RalGEFs are activators of the related RalA and RalB small GTPases and we found activation of both in CRC cell lines and patient tumors. Interfering RNA stable suppression of RalA expression reduced CRC tumor cell anchorage-independent growth, but surprisingly, stable suppression of RalB greatly enhanced soft agar colony size and formation frequency. Despite their opposing activities, both RalA and RalB regulation of anchorage-independent growth required interaction with RalBP1/RLIP76 and components of the exocyst complex. Interestingly, RalA interaction with the Exo84 but not Sec5 exocyst component was necessary for supporting anchorage-independent growth, whereas RalB interaction with Sec5 but not Exo84 was necessary for inhibition of anchorage-independent growth. We suggest that anti-RalA–selective therapies may provide an effective approach for KRAS mutant CRC. Cancer Res; 71(1); 206–15. ©2010 AACR.
Data from A Placental Growth Factor Variant Unable to Recognize Vascular Endothelial Growth Factor (VEGF) Receptor-1 Inhibits VEGF-Dependent Tumor Angiogenesis via Heterodimerization
Authors: Tarallo Valeria , Vesci Loredana , Capasso Onofrio , Esposito Maria Teresa , Riccioni Teresa , Pastore Lucio , Orlandi Augusto , Pisano Claudio , De Falco Sandro
Published: March 2024

Abstract
Angiogenesis is one of the crucial events for cancer development and growth. Two members of the vascular endothelial growth factor (VEGF) family, VEGF-A and placental growth factor (PlGF), which are able to heterodimerize if coexpressed in the same cell, are both required for pathologic angiogenesis. We have generated a PlGF1 variant, named PlGF1-DE in which the residues Asp72 and Glu73 were substituted with Ala, which is unable to bind and activate VEGF receptor-1 but is still able to heterodimerize with VEGF. Here, we show that overexpression in tumor cells by adenoviral delivery or stable transfection of PlGF1-DE variant significantly reduces the production of VEGF homodimer via heterodimerization, determining a strong inhibition of xenograft tumor growth and neoangiogenesis, as well as significant reduction of vessel lumen and stabilization, and monocyte-macrophage infiltration. Conversely, the overexpression of PlGF1wt, also reducing the VEGF homodimer production comparably with PlGF1-DE variant through the generation of VEGF/PlGF heterodimer, does not inhibit tumor growth and vessel density compared with controls but induces increase of vessel lumen, vessel stabilization, and monocyte-macrophage infiltration. The property of PlGF and VEGF-A to generate heterodimer represents a successful strategy to inhibit VEGF-dependent angiogenesis. The PlGF1-DE variant, and not PlGF1wt as previously reported, acts as a “dominant negative” of VEGF and is a new candidate for antiangiogenic gene therapy in cancer treatment. Cancer Res; 70(5); 1804–13
Data from Matrix Metalloproteinase (MMP)-13 Regulates Mammary Tumor–Induced Osteolysis by Activating MMP9 and Transforming Growth Factor-β Signaling at the Tumor-Bone Interface
Authors: Nannuru Kalyan C. , Futakuchi Mitsuru , Varney Michelle L. , Vincent Thomas M. , Marcusson Eric G. , Singh Rakesh K.
Published: March 2024

Abstract
The tropism of breast cancer cells for bone and their tendency to induce an osteolytic phenotype are a result of interactions between breast cancer cells and stromal cells and are of paramount importance for bone metastasis. However, the underlying molecular mechanisms remain poorly understood. We hypothesize that tumor-stromal interaction alters gene expression in malignant tumor cells and stromal cells creating a unique expression signature that promotes osteolytic breast cancer bone metastasis and that inhibition of such interactions can be developed as targeted therapeutics. Microarray analysis was performed to investigate gene expression profiling at the tumor-bone (TB) interface versus the tumor alone area from syngenic mice injected with three different syngenic mammary tumor cell lines that differ in their metastatic potential. We identified matrix metalloproteinase 13 (MMP13), receptor activator of NF-κB ligand (RANKL), and integrins binding sialoprotein to be genes upregulated at the TB interface and validated. To determine the functional role of MMP13 in tumor-induced osteolysis, mice with Cl66 mammary tumors were treated with MMP13 antisense oligonucleotides (MMP13-ASO) or control scrambled oligonucleotides (control-ASO). Knockdown of MMP13 expression at the TB interface leads to significant reduction in bone destruction and in the number of activated osteoclasts at the TB interface. Further analysis to evaluate the mechanism of MMP13-dependent osteolytic bone metastasis revealed that MMP13-ASO treatment decreased active MMP9, RANKL levels, and transforming growth factor-β signaling at the TB interface. Together, our data indicate that upregulation of MMP13 at the TB interface is important in tumor-induced osteolysis and suggest that MMP13 is a potential therapeutic target for breast cancer bone metastasis. Cancer Res; 70(9); 3494–504. ©2010 AACR.
Data from Mathematical and Experimental Approaches to Identify and Predict the Effects of Chemotherapy on Neuroglial Precursors
Authors: Hyrien Ollivier , Dietrich Jörg , Noble Mark
Published: March 2024

Abstract
The adverse effects of chemotherapy on normal cells of the body create substantial clinical problems for many cancer patients. However, relatively little is known about the effects, other than promotion of cell death, of such agents on the function of normal precursor cells critical in tissue homeostasis and repair. We have combined mathematical and experimental analyses to identify the effects of sublethal doses of chemotherapy on glial precursor cells of the central nervous system. We modeled the temporal development of a population of precursor and terminally differentiated cells exposed to sublethal doses of carmustine (BCNU), a classic alkylating chemotherapeutic agent used in treatment of gliomas and non-Hodgkin's lymphomas, as a multitype age-dependent branching process. We fitted our model to data from in vitro clonal experiments using the method of pseudo-likelihood. This approach identifies several novel drug effects, including modification of the cell cycle length, the time between division and differentiation, and alteration in the probability of undergoing self-renewal division in precursor cells. These changes of precursor cell function in the chemotherapy-exposed brain may have profound clinic implications.

Major Findings: We applied our computational approach to analyze the effects of BCNU on clonal cultures of oligodendrocyte progenitor cells—one of the best-characterized neural progenitor cells in the mammalian brain. Our analysis reveals that transient exposures to BCNU increased the cell cycle length of progenitor cells and decreased their time to differentiation, while also decreasing the likelihood that they will undergo self-renewing divisions. By investigating the behavior of our mathematical model, we demonstrate that precursor cell populations should recover spontaneously from transient modifications of the timing of division and of differentiation, but such recovery will not happen after alteration of cell fate. These studies identify means by which precursor cell function can be critically compromised by transient exposure to chemotherapy with long-term consequences on the progenitor cell pool even in the absence of drug-induced apoptosis. These analyses also provide novel tools that apply broadly to identify effects of chemotherapeutic agents and other physiological stressors. Cancer Res; 70(24); 10051–9. ©2010 AACR.
Data from Exon Array Analyses across the NCI-60 Reveal Potential Regulation of TOP1 by Transcription Pausing at Guanosine Quartets in the First Intron
Authors: Reinhold William C. , Mergny Jean-Louis , Liu Hongfang , Ryan Michael , Pfister Thomas D. , Kinders Robert , Parchment Ralph , Doroshow James , Weinstein John N. , Pommier Yves
Published: March 2024

Abstract
Because topoisomerase 1 (TOP1) is critical for the relaxation of DNA supercoils and because it is the target for the anticancer activity of camptothecins, we assessed TOP1 transcript levels in the 60 cell line panel (the NCI-60) of the National Cancer Institute's anticancer drug screen. TOP1 expression levels varied over a 5.7-fold range across the NCI-60. HCT116 colon and MCF-7 breast cancer cells were the highest expressers; SK-MEL-28 melanoma and HS578T breast carcinoma cells were the lowest. TOP1 mRNA expression was highly correlated with Top1 protein levels, indicating that TOP1 transcripts could be conveniently used to monitor Top1 protein levels and activity in tissues. Assessment of the TOP1 locus by array comparative genomic hybridization across the NCI-60 showed copy numbers ranging from 1.71 to 4.13 and a statistically significant correlation with TOP1 transcript levels (P < 0.01). Further analyses of TOP1 expression on an exon-specific basis revealed that exon 1 expression was generally higher and less variable than expression of the other exons, suggesting some form of transcriptional pausing regulation between exons 1 and 2. Accordingly, we found the presence of multiple evolutionarily conserved potential G-quadruplex–forming sequences in the first TOP1 intron. Physicochemical tests for actual quadruplex formation by several of those sequences yielded quadruplex formation for two of them and duplex formation for one. The observations reported here suggest the hypothesis that there is a conserved negative transcription regulator within intron 1 of the TOP1 gene associated with a quadruplex-prone region. Cancer Res; 70(6); 2191–203
Data from Insulin-Like Growth Factor I Suppresses Bone Morphogenetic Protein Signaling in Prostate Cancer Cells by Activating mTOR Signaling
Authors: Wahdan-Alaswad Reema S. , Song Kyung , Krebs Tracy L. , Shola Dorjee T.N. , Gomez Jose A. , Matsuyama Shigemi , Danielpour David
Published: March 2024

Abstract
Insulin-like growth factor (IGF) I and bone morphogenetic proteins (BMP) are critical regulators of prostate tumor cell growth. In this report, we offer evidence that a critical support of IGF-I in prostate cancer is mediated by its ability to suppress BMP4-induced apoptosis and Smad-mediated gene expression. Suppression of BMP4 signaling by IGF-I was reversed by chemical inhibitors of phosphoinositide 3-kinase (PI3K), Akt, or mTOR; by enforced expression of wild-type PTEN or dominant-negative PI3K; or by small hairpin RNA–mediated silencing of mTORC1/2 subunits Raptor or Rictor. Similarly, IGF-I suppressed BMP4-induced transcription of the Id1, Id2, and Id3 genes that are crucially involved in prostate tumor progression through PI3K-dependent and mTORC1/2-dependent mechanisms. Immunohistochemical analysis of non-malignant and malignant prostate tissues offered in vivo support for our model that IGF-I–mediated activation of mTOR suppresses phosphorylation of the BMP-activated Smad transcription factors. Our results offer the first evidence that IGF-I signaling through mTORC1/2 is a key homeostatic regulator of BMP4 function in prostate epithelial cells, acting at two levels to repress both the proapoptotic and pro-oncogenic signals of BMP-activated Smads. We suggest that deregulation of this homeostatic control may be pivotal to the development and progression of prostate cancer, providing important implications and new potential targets for the therapeutic intervention of this malignancy. Cancer Res; 70(22); 9106–17. ©2010 AACR.
Data from ANCCA/ATAD2 Overexpression Identifies Breast Cancer Patients with Poor Prognosis, Acting to Drive Proliferation and Survival of Triple-Negative Cells through Control of B-Myb and EZH2
Authors: Kalashnikova Ekaterina V. , Revenko Alexey S. , Gemo Abigael T. , Andrews Nicolas P. , Tepper Clifford G. , Zou June X. , Cardiff Robert D. , Borowsky Alexander D. , Chen Hong-Wu
Published: March 2024

Abstract
Chromatin coregulators are important factors in tumorigenesis and cancer progression. ANCCA is an AAA+ ATPase and a bromodomain-containing nuclear coactivator for the estrogen and androgen receptors that is crucial for assembly of chromatin-modifying complexes and proliferation of hormone-responsive cancer cells. In this study, we show that ANCCA is overexpressed in >70% of breast tumors and that its high protein level correlates well with tumor histologic grades (P < 0.0001), highlighting ANCCA as a prognostic factor for poor overall survival and disease recurrence. Strikingly, high-level ANCCA correlated with triple-negative tumors that represent highly aggressive disease. Analysis of ANCCA transcript levels in multiple expression profiles of breast cancer identified ANCCA as a common signature gene, indicating that elevated transcripts also strongly correlate with tumor metastasis and poor survival. Biological and mechanistic investigations revealed that ANCCA is crucial for proliferation and survival of triple-negative/basal-like cancer cells and that it controls the expression of B-Myb, histone methyltransferase EZH2, and an Rb-E2F core program for proliferation, along with a subset of key mitotic kinesins and cell survival genes (IRS2, VEGF, and Akt1). In particular, ANCCA overexpression correlated strongly with EZH2 in tumors. Our results suggest that ANCCA may integrate multiple oncogenic programs in breast cancer, serving in particular as a prognostic marker and a therapeutic target for triple-negative cancers. Cancer Res; 70(22); 9402–12. ©2010 AACR.
Data from p190RhoGEF (Rgnef) Promotes Colon Carcinoma Tumor Progression via Interaction with Focal Adhesion Kinase
Authors: Yu Hong-Gang , Nam Ju-Ock , Miller Nichol L. G. , Tanjoni Isabelle , Walsh Colin , Shi Lei , Kim Linda , Chen Xiao Lei , Tomar Alok , Lim Ssang-Taek , Schlaepfer David D.
Published: March 2024

Abstract
Focal adhesion kinase (FAK) functions downstream of integrins and growth factor receptors to promote tumor cell motility and invasion. In colorectal cancer, FAK is activated by amidated gastrin, a protumorigenic hormone. However, it is unclear how FAK receives signals from the gastrin receptor or other G-protein–coupled receptors that can promote cell motility and invasion. The Rho guanine-nucleotide exchange factor p190RhoGEF (Rgnef) binds FAK and facilitates fibroblast focal adhesion formation on fibronectin. Here we report that Rgnef mRNA and protein expression are significantly increased during colorectal tumor progression. In human colon carcinoma cells, Rgnef forms a complex with FAK and upon gastrin stimulation, FAK translocates to newly-forming focal adhesions where it facilitates tyrosine phosphorylation of paxillin. short hairpin (shRNA)-mediated knockdown of Rgnef or FAK, or pharmacological inhibition of FAK activity, is sufficient to block gastrin-stimulated paxillin phosphorylation, cell motility, and invadopodia formation in a manner dependent upon upstream cholecystokinin-2 receptor expression. Overexpression of the C-terminal region of Rgnef (Rgnef-C, amino acid 1,279–1,582) but not Rgnef-CΔFAK (amino acid 1,302–1,582 lacking the FAK binding site) disrupted endogenous Rgnef-FAK interaction and prevented paxillin phosphorylation and cell motility stimulated by gastrin. Rgnef-C–expressing cells formed smaller, less invasive tumors with reduced tyrosine phosphorylation of paxillin upon orthotopic implantation, compared with Rgnef-CΔFAK–expressing cells. Our studies identify Rgnef as a novel regulator of colon carcinoma motility and invasion, and they show that a Rgnef–FAK linkage promotes colon carcinoma progression in vivo. Cancer Res; 71(2); 360–70. ©2011 AACR.
Data from Unraveling Cancer Chemoimmunotherapy Mechanisms by Gene and Protein Expression Profiling of Responses to Cyclophosphamide
Authors: Moschella Federica , Valentini Mara , Aricò Eleonora , Macchia Iole , Sestili Paola , D'Urso Maria Teresa , Alessandri Cristiano , Belardelli Filippo , Proietti Enrico
Published: March 2024

Abstract
Certain chemotherapeutic drugs, such as cyclophosphamide (CTX), can enhance the antitumor efficacy of immunotherapy because of their capacity to modulate innate and adaptive immunity. Indeed, it has been argued that this capacity may be more significant to chemotherapeutic efficacy in general than is currently appreciated. To gain insights into the core mechanisms of chemoimmunotherapy, we methodically profiled the effects of CTX on gene expression in bone marrow, spleen, and peripheral blood, and on cytokine expression in plasma and bone marrow of tumor-bearing mice. Gene and protein expression were modulated early and transiently by CTX, leading to upregulation of a variety of immunomodulatory factors, including danger signals, pattern recognition receptors, inflammatory mediators, growth factors, cytokines, chemokines, and chemokine receptors. These factors are involved in sensing CTX myelotoxicity and activating repair mechanisms, which, in turn, stimulate immunoactivation events that promote efficacy. In particular, CTX induced a T-helper 17 (Th17)-related gene signature associated with an increase in Th17, Th1, and activated CD25+CD4+Foxp3− T lymphocytes and a slight recovery of regulatory T cells. By analyzing gene and protein expression kinetics and their relationship to the antitumor efficacy of different therapeutic schedules of combination, we determined that optimal timing for performing adoptive immunotherapy is approximately 1 day after CTX treatment. Together, our findings highlight factors that may propel the efficacy of chemoimmunotherapy, offering a mechanistic glimpse of the important immune modulatory effects of CTX. Cancer Res; 71(10); 3528–39. ©2011 AACR.
Data from Tumor Galectin-1 Mediates Tumor Growth and Metastasis through Regulation of T-Cell Apoptosis
Authors: Banh Alice , Zhang Jing , Cao Hongbin , Bouley Donna M. , Kwok Shirley , Kong Christina , Giaccia Amato J. , Koong Albert C. , Le Quynh-Thu
Published: March 2024

Abstract
Galectin-1 (Gal-1), a carbohydrate-binding protein whose secretion is enhanced by hypoxia, promotes tumor aggressiveness by promoting angiogenesis and T-cell apoptosis. However, the importance of tumor versus host Gal-1 in tumor progression is undefined. Here we offer evidence that implicates tumor Gal-1 and its modulation of T-cell immunity in progression. Comparing Gal-1–deficient mice as hosts for Lewis lung carcinoma cells where Gal-1 levels were preserved or knocked down, we found that tumor Gal-1 was more critical than host Gal-1 in promoting tumor growth and spontaneous metastasis. Enhanced growth and metastasis associated with Gal-1 related to its immunomodulatory function, insofar as the benefits of Gal-1 expression to Lewis lung carcinoma growth were abolished in immunodeficient mice. In contrast, angiogenesis, as assessed by microvessel density count, was similar between tumors with divergent Gal-1 levels when examined at a comparable size. Our findings establish that tumor rather than host Gal-1 is responsible for mediating tumor progression through intratumoral immunomodulation, with broad implications in developing novel targeting strategies for Gal-1 in cancer. Cancer Res; 71(13); 4423–31. ©2011 AACR.
Data from Targeting the p53 Pathway in Retinoblastoma with Subconjunctival Nutlin-3a
Authors: Brennan Rachel C. , Federico Sara , Bradley Cori , Zhang Jiakun , Flores-Otero Jacqueline , Wilson Matthew , Stewart Clinton , Zhu Fangyi , Guy Kip , Dyer Michael A.
Published: March 2024

Abstract
Retinoblastoma is a rare childhood cancer of the retina that begins in utero and is diagnosed in the first years of life. The goals of retinoblastoma treatment are ocular salvage, vision preservation, and reduction of short- and long-term side effects without risking mortality because of tumor dissemination. To identify better chemotherapeutic combinations for the treatment of retinoblastoma, several groups have developed genetic mouse models and orthotopic xenograft models of human retinoblastoma for preclinical testing. Previous studies have implicated the MDMX protein in the suppression of the p53 pathway in retinoblastoma and shown that the MDM2/MDMX antagonist, Nutlin-3a, can efficiently induce p53-mediated cell death in retinoblastoma cell lines. However, Nutlin-3a cannot be administered systemically to treat retinoblastoma, because it has poor penetration across the blood–ocular barrier. Therefore, we developed an ocular formulation of Nutlin-3a, Nutlin-3aOC, and tested the pharmacokinetics and efficacy of this new formulation in genetic and human retinoblastoma orthotopic xenograft models of retinoblastoma. Here, we show that Nutlin-3aOC specifically and efficiently targets the p53 pathway and that the combination of Nutlin-3aOC with systemic topotecan is a significantly better treatment for retinoblastoma than currently used chemotherapy in human orthotopic xenografts. Our studies provide a new standardized approach to evaluate and prioritize novel agents for incorporation into future clinical trials for retinoblastoma. Cancer Res; 71(12); 4205–13. ©2011 AACR.
Data from Oncogenic Kras Promotes Chemotherapy-Induced Growth Factor Shedding via ADAM17
Authors: Van Schaeybroeck Sandra , Kyula Joan N. , Fenton Audrey , Fenning Catherine S. , Sasazuki Takehiko , Shirasawa Senji , Longley Daniel B. , Johnston Patrick G.
Published: March 2024

Abstract
Oncogenic mutations in Kras occur in 40% to 45% of patients with advanced colorectal cancer (CRC). We have previously shown that chemotherapy acutely activates ADAM17, resulting in growth factor shedding, growth factor receptor activation, and drug resistance in CRC tumors. In this study, we examined the role of mutant Kras in regulating growth factor shedding and ADAM17 activity, using isogenic Kras mutant (MT) and wild-type (WT) HCT116 CRC cells. Significantly higher levels of TGF-α and VEGF were shed from KrasMT HCT116 cells, both basally and following chemotherapy treatment, and this correlated with increased pErk (phosphorylated extracellular signal regulated kinase)1/2 levels and ADAM17 activity. Inhibition of Kras, MEK (MAP/ERK kinase)1/2, or Erk1/2 inhibition abrogated chemotherapy-induced ADAM17 activity and TGF-α shedding. Moreover, we found that these effects were not drug or cell line specific. In addition, MEK1/2 inhibition in KrasMT xenografts resulted in significant decreases in ADAM17 activity and growth factor shedding in vivo, which correlated with dramatically attenuated tumor growth. Furthermore, we found that MEK1/2 inhibition significantly induced apoptosis both alone and when combined with chemotherapy in KrasMT cells. Importantly, we found that sensitivity to MEK1/2 inhibition was ADAM17 dependent in vitro and in vivo. Collectively, our findings indicate that oncogenic Kras regulates ADAM17 activity and thereby growth factor ligand shedding in a MEK1/2/Erk1/2-dependent manner and that KrasMT CRC tumors are vulnerable to MEK1/2 inhibitors, at least in part, due to their dependency on ADAM17 activity. Cancer Res; 71(3); 1071–80. ©2010 AACR.
Data from IRF-1 Expression Is Essential for Natural Killer Cells to Suppress Metastasis
Authors: Ksienzyk Antje , Neumann Berit , Nandakumar Ramya , Finsterbusch Katja , Grashoff Martina , Zawatzky Rainer , Bernhardt Günter , Hauser Hansjörg , Kröger Andrea
Published: March 2024

Abstract
IFN-γ promotes tumoral immune surveillance, but its involvement in controlling metastases is less clear. Using a mouse model of pulmonary metastases, we show that local IFN-γ treatment inhibits formation of metastases through its regulation of IRF-1 in tumor cells. IRF-1 is an IFN-γ–induced transcription factor pivotal in the regulation of infection and inflammation. IRF-1 blockade abolished the inhibitory effect of IFN-γ on tumor metastases, whereas ectopic expression of IRF-1 phenocopied the inhibitory effects of IFN-γ. IRF-1 did not affect the survival of tumor cells in the circulation or their infiltration into lungs, but it was essential to support the pulmonary attraction and activation of natural killer (NK) cells. Depleting NK cells from mice abolished the protective effect of IFN-γ or IRF-1 on metastases. In addition, cytotoxicity assays revealed that tumor cells expressing IRF-1 were targeted more effectively by NK cells than IRF-1 nonexpressing tumor cells. Moreover, NK cells isolated from lungs inoculated with IRF-1–expressing tumor cells exhibit a greater cytotoxic activity. Mechanistic investigations revealed that IRF-1–induced NK cell cytotoxicity was independent of perforin and granzyme B but dependent on the NK cell activating receptor DNAM-1. Taken together, our findings establish IRF-1 as an essential mediator of the cross-talk between tumor cells and NK cells that mediate immune surveillance in the metastatic niche. Cancer Res; 71(20); 6410–8. ©2011 AACR.