bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Pesticide Use Modifies the Association Between Genetic Variants on Chromosome 8q24 and Prostate Cancer
Authors: Koutros Stella , Beane Freeman Laura E. , Berndt Sonja I. , Andreotti Gabriella , Lubin Jay H. , Sandler Dale P. , Hoppin Jane A. , Yu Kai , Li Qizhai , Burdette Laura A. , Yuenger Jeffrey , Yeager Meredith , Alavanja Michael C.R.
Published: March 2024

Abstract
Genome-wide association studies have identified 8q24 region variants as risk factors for prostate cancer. In the Agricultural Health Study, a prospective study of licensed pesticide applicators, we observed increased prostate cancer risk with specific pesticide use among those with a family history of prostate cancer. Thus, we evaluated the interaction among pesticide use, 8q24 variants, and prostate cancer risk. The authors estimated odds ratios (OR) and 95% confidence intervals (95% CI) for interactions among 211 8q24 variants, 49 pesticides, and prostate cancer risk in 776 cases and 1,444 controls. The ORs for a previously identified variant, rs4242382, and prostate cancer increased significantly (P < 0.05) with exposure to the organophosphate insecticide fonofos, after correction for multiple testing, with per allele ORnonexposed of 1.17 (95% CI, 0.93–1.48), per allele ORlow of 1.30 (95% CI, 0.75–2.27), and per allele ORhigh of 4.46 (95% CI, 2.17–9.17; P-interaction = 0.002, adjusted P-interaction = 0.02). A similar effect modification was observed for three other organophosphate insecticides (coumaphos, terbufos, and phorate) and one pyrethroid insecticide (permethrin). Among ever users of fonofos, subjects with three or four risk alleles at rs7837328 and rs4242382 had approximately three times the risk of prostate cancer (OR, 3.14; 95% CI, 1.41–7.00) compared with subjects who had zero risk alleles and never used fonofos. We observed a significant interaction among variants on chromosome 8q24, pesticide use, and risk of prostate cancer. Insecticides, particularly organophosphates, were the strongest modifiers of risk, although the biological mechanism is unclear. This is the first report of effect modification between 8q24 and an environmental exposure on prostate cancer risk. Cancer Res; 70(22); 9224–33. ©2010 AACR.
Data from Loss of Osteoclasts Contributes to Development of Osteosarcoma Pulmonary Metastases
Authors: Endo-Munoz Liliana , Cumming Andrew , Rickwood Danny , Wilson Danielle , Cueva Claudia , Ng Charlotte , Strutton Geoffrey , Cassady A. Ian , Evdokiou Andreas , Sommerville Scott , Dickinson Ian , Guminski Alexander , Saunders Nicholas A.
Published: March 2024

Abstract
We conducted a transcriptomic screen of osteosarcoma (OS) biopsies and found that expression of osteoclast-specific tartrate-resistant acid phosphatase 5 (ACP5/TRAP) is significantly downregulated in OS compared with nonmalignant bone (P < 0.0001). Moreover, lesions from OS patients with pulmonary metastases had 2-fold less ACP5/TRAP expression (P < 0.018) than lesions from patients without metastases. In addition, we found a direct correlation (P = 0.0166) between ACP5/TRAP expression and time to metastasis. Therefore, we examined whether metastasis-competent (MC) OS cells could induce loss of ACP5+ osteoclasts and contribute to metastasis. We found that MC OS cell lines can inhibit osteoclastogenesis in vitro and in vivo. In addition, osteoclasts can inhibit the migration of MC OS cells in vitro. Finally, ablation of osteoclasts with zoledronic acid increases the number of metastatic lung lesions in an orthotopic OS model, whereas fulvestrant treatment increases osteoclast numbers and reduces metastatic lesions. These data indicate that the metastatic potential of OS is determined early in tumor development and that loss of osteoclasts in the primary lesion enhances OS metastasis. Cancer Res; 70(18); 7063–72. ©2010 AACR.
Data from Epigenetically Deregulated microRNA-375 Is Involved in a Positive Feedback Loop with Estrogen Receptor α in Breast Cancer Cells
Authors: de Souza Rocha Simonini Pedro , Breiling Achim , Gupta Nibedita , Malekpour Mahdi , Youns Mahmoud , Omranipour Ramesh , Malekpour Fatemeh , Volinia Stefano , Croce Carlo M. , Najmabadi Hossein , Diederichs Sven , Sahin Özgür , Mayer Doris , Lyko Frank , Hoheisel Jörg D. , Riazalhosseini Yasser
Published: March 2024

Abstract
Estrogen receptor α (ERα) upregulation causes abnormal cell proliferation in about two thirds of breast cancers, yet understanding of the underlying mechanisms remains incomplete. Here, we show that high expression of the microRNA miR-375 in ERα-positive breast cell lines is a key driver of their proliferation. miR-375 overexpression was caused by loss of epigenetic marks including H3K9me2 and local DNA hypomethylation, dissociation of the transcriptional repressor CTCF from the miR-375 promoter, and interactions of ERα with regulatory regions of miR-375. Inhibiting miR-375 in ERα-positive MCF-7 cells resulted in reduced ERα activation and cell proliferation. A combination of expression profiling from tumor samples and miRNA target prediction identified RASD1 as a potential miR-375 target. Mechanistic investigations revealed that miR-375 regulates RASD1 by targeting the 3′ untranslated region in RASD1 mRNA. Additionally, we found that RASD1 negatively regulates ERα expression. Our findings define a forward feedback pathway in control of ERα expression, highlighting new strategies to treat ERα-positive invasive breast tumors. Cancer Res; 70(22); 9175–84. ©2010 AACR.
Data from Liver Cancer Protease Activity Profiles Support Therapeutic Options with Matrix Metalloproteinase–Activatable Oncolytic Measles Virus
Authors: Mühlebach Michael D. , Schaser Thomas , Zimmermann Martina , Armeanu Sorin , Hanschmann Kay-Martin O. , Cattaneo Roberto , Bitzer Michael , Lauer Ulrich M. , Cichutek Klaus , Buchholz Christian J.
Published: March 2024

Abstract
Primary and secondary cancers of the liver are a significant health problem with limited treatment options. We sought here to develop an oncolytic measles virus (MV) preferentially activated in liver tumor tissue, thus reducing infection and destruction of healthy tissue. We documented that in primary tumor tissue, urokinase-type plasminogen activator and especially matrix metallproteinase-2 (MMP-2) are significantly more active than in adjacent nontumorous tissue. We then generated variants of the MV fusion protein by inserting different MMP substrate motifs at the protease cleavage site and identified the motif PQGLYA as the most efficient cleavage site as determined by syncytia formation on protease-positive tumor cells. The corresponding MMP-activatable oncolytic MV-MMPA1 virus was rescued and shown to be strongly restricted on primary human hepatocytes and healthy human liver tissue, while remaining as effective as the parental MV in the tumor tissue sections. Our findings underline the clinical potency of the MMP activation concept as a strategy to generate safer oncolytic viruses for the treatment of primary and secondary cancers of the liver. Cancer Res; 70(19); 7620–9. ©2010 AACR.
Data from Implication of Metastasis Suppressor NM23-H1 in Maintaining Adherens Junctions and Limiting the Invasive Potential of Human Cancer Cells
Authors: Boissan Mathieu , De Wever Olivier , Lizarraga Floria , Wendum Dominique , Poincloux Renaud , Chignard Nicolas , Desbois-Mouthon Christèle , Dufour Sylvie , Nawrocki-Raby Béatrice , Birembaut Philippe , Bracke Marc , Chavrier Philippe , Gespach Christian , Lacombe Marie-Lise
Published: March 2024

Abstract
Loss of NM23-H1 expression correlates with the degree of metastasis and with unfavorable clinical prognosis in several types of human carcinoma. However, the mechanistic basis for the metastasis suppressor function of NM23-H1 is obscure. We silenced NM23-H1 expression in human hepatoma and colon carcinoma cells and methodologically investigated effects on cell-cell adhesion, migration, invasion, and signaling linked to cancer progression. NM23-H1 silencing disrupted cell-cell adhesion mediated by E-cadherin, resulting in β-catenin nuclear translocation and T-cell factor/lymphoid-enhancing factor-1 transactivation. Further, NM23-H1 silencing promoted cellular scattering, motility, and extracellular matrix invasion by promoting invadopodia formation and upregulating several matrix metalloproteinases (MMP), including membrane type 1 MMP. In contrast, silencing the related NM23-H2 gene was ineffective at promoting invasion. NM23-H1 silencing activated proinvasive signaling pathways involving Rac1, mitogen-activated protein kinases, phosphatidylinositol 3-kinase (PI3K)/Akt, and src kinase. Conversely, NM23-H1 was dispensable for cancer cell proliferation in vitro and liver regeneration in NM23-M1 null mice, instead inducing cellular resistance to chemotherapeutic drugs in vitro. Analysis of NM23-H1 expression in clinical specimens revealed high expression in premalignant lesions (liver cirrhosis and colon adenoma) and the central body of primary liver or colon tumors, but downregulation at the invasive front of tumors. Our findings reveal that NM23-H1 is critical for control of cell-cell adhesion and cell migration at early stages of the invasive program in epithelial cancers, orchestrating a barrier against conversion of in situ carcinoma into invasive malignancy. Cancer Res; 70(19); 7710–22. ©2010 AACR.
Data from ADAMTS1 Contributes to the Acquisition of an Endothelial-like Phenotype in Plastic Tumor Cells
Authors: Casal Carmen , Torres-Collado Antoni Xavier , Plaza-Calonge María del Carmen , Martino-Echarri Estefanía , Ramón y Cajal Santiago , Rojo Federico , Griffioen Arjan W. , Rodríguez-Manzaneque Juan Carlos
Published: March 2024

Abstract
Cancer stem cells have been hypothesized to explain tumor plasticity, including the capability to adopt distinct differentiation commitments. Among the mechanisms of tumor neovascularization, the ability of some malignant cells to mimic an endothelial phenotype has been recognized by a capacity to form matrix-enriched pseudovascular structures. In addition to the expression of genes associated with an endothelial nature, the molecular dynamism of specific microenvironments may also be critical. Here, we report the identification of the extracellular protease ADAMTS1 as a critical molecule for tumor cells to acquire endothelial-like properties. In a fibrosarcoma model, ADAMTS1 increased tumor growth rate in an angiogenesis-independent manner, influencing the tumor cells to display an exclusive endothelial-like gene signature. We documented the relevant expression of ADAMTS1 in aggressive and highly plastic melanoma and Ewing sarcoma cells. Notably, inhibiting ADAMTS1 action compromised the endothelial mimetic attributes observed in this setting. Our findings provide insights into how the tumor microenvironment can elicit endothelial mimicry by tumor cells. Cancer Res; 70(11); 4676–86. ©2010 AACR.
Data from Novel Metastasis-Related Gene CIM Functions in the Regulation of Multiple Cellular Stress–Response Pathways
Authors: Yanagisawa Kiyoshi , Konishi Hiroyuki , Arima Chinatsu , Tomida Shuta , Takeuchi Toshiyuki , Shimada Yukako , Yatabe Yasushi , Mitsudomi Tetsuya , Osada Hirotaka , Takahashi Takashi
Published: March 2024

Abstract
Various stresses of the tumor microenvironment produced by insufficient nutrients, pH, and oxygen can contribute to the generation of altered metabolic and proliferative states that promote the survival of metastatic cells. Among many cellular stress–response pathways activated under such conditions are the hypoxia-inducible factor (HIF) pathway and the unfolded protein response (UPR), which is elicited as a response to endoplasmic reticulum (ER) stress. In this study, we report the identification of a novel cancer invasion and metastasis-related gene (hereafter referred to as CIM, also called ERLEC1), which influences both of these stress–response pathways to promote metastasis. CIM was identified by comparing the gene expression profile of a highly metastatic human lung cancer cell line with its weakly metastatic parental clone. We showed that CIM is critical for metastatic properties in this system. Proteomic approaches combined with bioinformatic analyses revealed that CIM has multifaceted roles in controlling the response to hypoxia and ER stress. Specifically, CIM sequestered OS-9 from the HIF-1α complex and PHD2, permitting HIF-1α accumulation by preventing its degradation. Ectopic expression of CIM in lung cancer cells increased their tolerance to hypoxia. CIM also modulated UPR through interaction with the key ER stress protein BiP, influencing cell proliferation under ER stress conditions. Our findings shed light on how tolerance to multiple cellular stresses at a metastatic site can be evoked by an integrated mechanism involving CIM, which can function to coordinate those responses in a manner that promotes metastatic cell survival. Cancer Res; 70(23); 9949–58. ©2010 AACR.
Data from Selective BRAFV600E Inhibition Enhances T-Cell Recognition of Melanoma without Affecting Lymphocyte Function
Authors: Boni Andrea , Cogdill Alexandria P. , Dang Ping , Udayakumar Durga , Njauw Ching-Ni Jenny , Sloss Callum M. , Ferrone Cristina R. , Flaherty Keith T. , Lawrence Donald P. , Fisher David E. , Tsao Hensin , Wargo Jennifer A.
Published: March 2024

Abstract
Targeted therapy against the BRAF/mitogen-activated protein kinase (MAPK) pathway is a promising new therapeutic approach for the treatment of melanoma. Treatment with selective BRAF inhibitors results in a high initial response rate but limited duration of response. To counter this, investigators propose combining this therapy with other targeted agents, addressing the issue of redundancy and signaling through different oncogenic pathways. An alternative approach is combining BRAF/MAPK-targeted agents with immunotherapy. Preliminary evidence suggests that oncogenic BRAF (BRAFV600E) contributes to immune escape and that blocking its activity via MAPK pathway inhibition leads to increased expression of melanocyte differentiation antigens (MDA). Recognition of MDAs is a critical component of the immunologic response to melanoma, and several forms of immunotherapy capitalize on this recognition. Among the various approaches to inhibiting BRAF/MAPK, broad MAPK pathway inhibition may have deleterious effects on T lymphocyte function. Here, we corroborate the role of oncogenic BRAF in immune evasion by melanoma cells through suppression of MDAs. We show that inhibition of the MAPK pathway with MAPK/extracellular signal-regulated kinase kinase (MEK) inhibitors or a specific inhibitor of BRAFV600E in melanoma cell lines and tumor digests results in increased levels of MDAs, which is associated with improved recognition by antigen-specific T lymphocytes. However, treatment with MEK inhibitors impairs T lymphocyte function, whereas T-cell function is preserved after treatment with a specific inhibitor of BRAFV600E. These findings suggest that immune evasion of melanomas mediated by oncogenic BRAF may be reversed by targeted BRAF inhibition without compromising T-cell function. These findings have important implications for combined kinase-targeted therapy plus immunotherapy for melanoma. Cancer Res; 70(13); 5213–9. ©2010 AACR.
Data from Nucleotide Excision Repair Gene Expression after Cisplatin Treatment in Melanoma
Authors: Bowden Nikola A. , Ashton Katie A. , Avery-Kiejda Kelly A. , Zhang Xu Dong , Hersey Peter , Scott Rodney J.
Published: March 2024

Abstract
Two of the hallmark features of melanoma are its development as a result of chronic UV radiation exposure and the limited efficacy of cisplatin in the disease treatment. Both of these DNA-damaging agents result in large helix-distorting DNA damage that is recognized and repaired by nucleotide excision repair (NER). The aim of this study was to examine the expression of NER gene transcripts, p53, and p21 in melanoma cell lines treated with cisplatin compared with melanocytes. Basal expression of all genes was greater in the melanoma cell lines compared with melanocytes. Global genome repair (GGR) transcripts showed significantly decreased relative expression (RE) in melanoma cell lines 24 hours after cisplatin treatment. The basal RE of p53 was significantly higher in the melanoma cell lines compared with the melanocytes. However, induction of p53 was only significant in the melanocytes at 6 and 24 hours after cisplatin treatment. Inhibition of p53 expression significantly decreased the expression of all the GGR transcripts in melanocytes at 6 and 24 hours after cisplatin treatment. Although the RE levels were lower with p53 inhibition, the induction of the GGR genes was very similar to that in the control melanocytes and increased significantly across the time points. The findings from this study revealed reduced GGR transcript levels in melanoma cells 24 hours after cisplatin treatment. Our findings suggest a possible mechanistic explanation for the limited efficacy of cisplatin treatment and the possible role of UV light in melanoma. Cancer Res; 70(20); 7918–26. ©2010 AACR.
Data from Cell-Permeable Peptide DEPDC1-ZNF224 Interferes with Transcriptional Repression and Oncogenicity in Bladder Cancer Cells
Authors: Harada Yosuke , Kanehira Mitsugu , Fujisawa Yoshiko , Takata Ryo , Shuin Taro , Miki Tsuneharu , Fujioka Tomoaki , Nakamura Yusuke , Katagiri Toyomasa
Published: March 2024

Abstract
Bladder cancer is the second most common genitourinary cancer worldwide, yet its oncogenic origins remain poorly understood. The cancer-testis antigen DEPDC1 was shown recently to contribute to bladder cancer oncogenesis. In this study, we examined the biological functions of DEPDC1 and defined a potential therapeutic strategy to target this molecule. Coimmunoprecipitation and immunocytochemistry revealed that DEPDC1 interacted and colocalized with zinc finger transcription factor ZNF224, a known transcriptional repressor. Inhibiting this interaction with a cell-permeable peptide corresponding to the ZNF224-interacting domain in DEPDC1 induced apoptosis of bladder cancer cells in vitro and in vivo. By inhibiting DEPDC1-ZNF224 complex formation, this peptide triggered transcriptional activation of A20, a potent inhibitor of the NF-κB signaling pathway. Our findings indicate that the DEPDC1-ZNF224 complex is likely to play a critical role in bladder carcinogenesis. Cancer Res; 70(14); 5829–39. ©2010 AACR.
Data from SG2285, a Novel C2-Aryl-Substituted Pyrrolobenzodiazepine Dimer Prodrug That Cross-links DNA and Exerts Highly Potent Antitumor Activity
Authors: Hartley John A. , Hamaguchi Anzu , Coffils Marissa , Martin Christopher R.H. , Suggitt Marie , Chen Zhizhi , Gregson Stephen J. , Masterson Luke A. , Tiberghien Arnaud C. , Hartley Janet M. , Pepper Christopher , Lin Thet Thet , Fegan Christopher , Thurston David E. , Howard Philip W.
Published: March 2024

Abstract
The pyrrolobenzodiazepines (PBD) are naturally occurring antitumor antibiotics, and a PBD dimer (SJG-136, SG2000) is in phase II trials. Many potent PBDs contain a C2-endo-exo unsaturated motif associated with the pyrrolo C-ring. The novel compound SG2202 is a PBD dimer containing this motif. SG2285 is a water-soluble prodrug of SG2202 in which two bisulfite groups inactivate the PBD N10-C11 imines. Once the bisulfites are eliminated, the imine moieties can bind covalently in the DNA minor groove, forming an interstrand cross-link. The mean in vitro cytotoxic potency of SG2285 against human tumor cell lines is GI50 20 pmol/L. SG2285 is highly efficient at producing DNA interstrand cross-links in cells, but they form more slowly than those produced by SG2202. Cellular sensitivity to SG2285 was primarily dependent on ERCC1 and homologous recombination repair. In primary B-cell chronic lymphocytic leukemia samples, the mean LD50 was significantly lower than in normal age-matched B and T lymphocytes. Antitumor activity was shown in several human tumor xenograft models, including ovarian, non–small cell lung, prostate, pancreatic, and melanoma, with cures obtained in the latter model with a single dose. Further, in an advanced-stage colon model, SG2285 administered either as a single dose, or in two repeat dose schedules, was superior to irinotecan. Our findings define SG2285 as a highly active cytotoxic compound with antitumor properties desirable for further development. Cancer Res; 70(17); 6849–58. ©2010 AACR.
Data from p53 Is a Direct Transcriptional Target of MYCN in Neuroblastoma
Authors: Chen Lindi , Iraci Nunzio , Gherardi Samuele , Gamble Laura D. , Wood Katrina M. , Perini Giovanni , Lunec John , Tweddle Deborah A.
Published: March 2024

Abstract
MYCN amplification occurs in ∼25% of neuroblastomas, where it is associated with rapid tumor progression and poor prognosis. MYCN plays a paradoxical role in driving cellular proliferation and inducing apoptosis. Based on observations of nuclear p53 accumulation in neuroblastoma, we hypothesized that MYCN may regulate p53 in this setting. Immunohistochemical analysis of 82 neuroblastoma tumors showed an association of high p53 expression with MYCN expression and amplification. In a panel of 5 MYCN-amplified and 5 nonamplified neuroblastoma cell lines, and also in the Tet21N-regulatable MYCN expression system, we further documented a correlation between the expression of MYCN and p53. In MYCN-amplified neuroblastoma cell lines, MYCN knockdown decreased p53 expression. In Tet21N MYCN+ cells, higher levels of p53 transcription, mRNA, and protein were observed relative to Tet21N MYCN- cells. In chromatin immunoprecipitation and reporter gene assays, MYCN bound directly to a Myc E-Box DNA binding motif located close to the transcriptional start site within the p53 promoter, where it could initiate transcription. E-Box mutation decreased MYCN-driven transcriptional activation. Microarray analysis of Tet21N MYCN+/− cells identified several p53-regulated genes that were upregulated in the presence of MYCN, including MDM2 and PUMA, the levels of which were reduced by MYCN knockdown. We concluded that MYCN transcriptionally upregulates p53 in neuroblastoma and uses p53 to mediate a key mechanism of apoptosis. Cancer Res; 70(4); 1377–88
Data from MiR-199a-3p Regulates mTOR and c-Met to Influence the Doxorubicin Sensitivity of Human Hepatocarcinoma Cells
Authors: Fornari Francesca , Milazzo Maddalena , Chieco Pasquale , Negrini Massimo , Calin George Adrian , Grazi Gian Luca , Pollutri Daniela , Croce Carlo Maria , Bolondi Luigi , Gramantieri Laura
Published: March 2024

Abstract
MicroRNAs (miRNA) have rapidly emerged as modulators of gene expression in cancer in which they may have great diagnostic and therapeutic import. MicroRNA-199a-3p (miR-199a-3p) is downregulated in several human malignancies including hepatocellular carcinoma (HCC). Here, we show that miR-199a-3p targets mammalian target of rapamycin (mTOR) and c-Met in HCC cells. Restoring attenuated levels of miR-199a-3p in HCC cells led to G1-phase cell cycle arrest, reduced invasive capability, enhanced susceptibility to hypoxia, and increased sensitivity to doxorubicin-induced apoptosis. These in vitro findings were confirmed by an analysis of human HCC tissues, which revealed an inverse correlation linking miR-199a-3p and mTOR as well as a shorter time to recurrence after HCC resection in patients with lower miR-199a-3p expression. These results suggest that tactics to regulate mTOR and c-Met by elevating levels of miR-199a-3p may have therapeutic benefits in highly lethal cancers such as HCC. Cancer Res; 70(12); 5184–93. ©2010 AACR.
Data from Myxoma Virus Virotherapy for Glioma in Immunocompetent Animal Models: Optimizing Administration Routes and Synergy with Rapamycin
Authors: Lun XueQing , Alain Tommy , Zemp Franz J. , Zhou Hongyuan , Rahman Masmudur M. , Hamilton Mark G. , McFadden Grant , Bell John , Senger Donna L. , Forsyth Peter A.
Published: March 2024

Abstract
Oncolytic myxoma virus (MYXV) is being developed as a novel virotherapeutic against human brain cancer and has promising activity against human brain tumor models in immunocompromised hosts. Because an intact immune system could reduce its efficacy, the purpose of this study was to evaluate the oncolytic potential of MYXV in immunocompetent racine glioma models. Here, we report that MYXV infects and kills all racine cell glioma lines and that its effects are enhanced by rapamycin. Intratumoral administration of MYXV with rapamycin improved viral replication in the tumor and significantly prolonged host survival. Similarly, coadministration via a method of convection-enhanced delivery (CED) enhanced viral replication and efficacy in vivo. Mechanisms by which rapamycin improved MYXV oncolysis included an inhibition of type I IFN production in vitro and a reduction of intratumoral infiltration of CD68+ microglia/macrophages and CD163+ macrophages in vivo. Our findings define a method to improve MYXV efficacy against gliomas by rapamycin coadministration, which acts to promote immune responses engaged by viral delivery. Cancer Res; 70(2); 598–608
Data from Fibroblast Growth Factor Receptor 4 Regulates Tumor Invasion by Coupling Fibroblast Growth Factor Signaling to Extracellular Matrix Degradation
Authors: Sugiyama Nami , Varjosalo Markku , Meller Pipsa , Lohi Jouko , Hyytiäinen Marko , Kilpinen Sami , Kallioniemi Olli , Ingvarsen Signe , Engelholm Lars H. , Taipale Jussi , Alitalo Kari , Keski-Oja Jorma , Lehti Kaisa
Published: March 2024

Abstract
Aberrant expression and polymorphism of fibroblast growth factor receptor 4 (FGFR4) has been linked to tumor progression and anticancer drug resistance. We describe here a novel mechanism of tumor progression by matrix degradation involving epithelial-to-mesenchymal transition in response to membrane-type 1 matrix metalloproteinase (MT1-MMP, MMP-14) induction at the edge of tumors expressing the FGFR4-R388 risk variant. Both FGFR4 and MT1-MMP were upregulated in tissue biopsies from several human cancer types including breast adenocarcinomas, where they were partially coexpressed at the tumor/stroma border and tumor invasion front. The strongest overall coexpression was found in prostate carcinoma. Studies with cultured prostate carcinoma cell lines showed that the FGFR4-R388 variant, which has previously been associated with poor cancer prognosis, increased MT1-MMP–dependent collagen invasion. In this experimental model, knockdown of FGFR4-R388 or MT1-MMP by RNA interference blocked tumor cell invasion and growth in collagen. This was coupled with impaired phosphorylation of FGFR substrate 2 and Src, upregulation of E-cadherin, and suppression of cadherin-11 and N-cadherin. These in vitro results were substantiated by reduced MT1-MMP content and in vivo growth of prostate carcinoma cells after the FGFR4-R388 gene silencing. In contrast, knockdown of the alternative FGFR4-G388 allele enhanced MT1-MMP and invasive tumor cell growth in vivo and within three-dimensional collagen. These results will help to explain the reported association of the FGFR4-R388 variant with the progression and poor prognosis of certain types of tumors. Cancer Res; 70(20); 7851–61. ©2010 AACR.
Data from Immune Stimulatory Receptor CD40 Is Required for T-Cell Suppression and T Regulatory Cell Activation Mediated by Myeloid-Derived Suppressor Cells in Cancer
Authors: Pan Ping-Ying , Ma Ge , Weber Kaare J. , Ozao-Choy Junko , Wang George , Yin Bingjiao , Divino Celia M. , Chen Shu-Hsia
Published: March 2024

Abstract
Immune tolerance to tumors is often associated with accumulation of myeloid-derived suppressor cells (MDSC) and an increase in the number of T-regulatory cells (Treg). In tumor-bearing mice, MDSCs can themselves facilitate the generation of tumor-specific Tregs. In this study, we demonstrate that expression of the immune stimulatory receptor CD40 on MDSCs is required to induce T-cell tolerance and Treg accumulation. In an immune reconstitution model, adoptive transfer of Gr-1+CD115+ monocytic MDSCs derived from CD40-deficient mice failed to recapitulate the ability of wild-type MDSCs to induce tolerance and Treg development in vivo. Agonistic anti-CD40 antibodies phenocopied the effect of CD40 deficiency and also improved the therapeutic efficacy of IL-12 and 4-1BB immunotherapy in the treatment of advanced tumors. Our findings suggest that CD40 is essential not only for MDSC-mediated immune suppression but also for tumor-specific Treg expansion. Blockade of CD40-CD40L interaction between MDSC and Treg may provide a new strategy to ablate tumoral immune suppression and thereby heighten responses to immunotherapy. Cancer Res; 70(1); 99–108
Data from Tetraspanin CD151 Regulates Transforming Growth Factor β Signaling: Implication in Tumor Metastasis
Authors: Sadej Rafał , Romanska Hanna , Kavanagh Dean , Baldwin Gouri , Takahashi Takashi , Kalia Neena , Berditchevski Fedor
Published: March 2024

Abstract
Tetraspanin CD151 is associated with laminin-binding integrins and controls tumor cell migration and invasion. By analyzing responses of breast cancer cells to various growth factors, we showed that depletion of CD151 specifically attenuates transforming growth factor β1 (TGFβ1)–induced scattering and proliferation of breast cancer cells in three-dimensional Matrigel. CD151-dependent cell scattering requires its association with either α3β1 or α6 integrins, but it is independent of the recruitment of CD151 to tetraspanin-enriched microdomains. We also found that CD151 regulates the compartmentalization of TGF-β type I receptor (TβRI/ALK-5) and specifically controls the TGFβ1-induced activation of p38. In contrast, signaling leading to activation of Smad2/3, c-Akt, and Erk1/2 proteins was comparable in CD151(+) and CD151(−) cells. Attenuation of TGFβ1-induced responses correlated with reduced retention in the lung vascular bed, inhibition of pneumocyte-induced scattering of breast cancer cells in three-dimensional Matrigel, and decrease in experimental metastasis to the lungs. These results identify CD151 as a positive regulator of TGFβ1-initiated signaling and highlight the important role played by this tetraspanin in TGFβ1-induced breast cancer metastasis. Cancer Res; 70(14); 6059–70. ©2010 AACR.
Data from Induction of Human Epithelial Stem/Progenitor Expansion by FOXM1
Authors: Gemenetzidis Emilios , Elena-Costea Daniela , Parkinson Eric K. , Waseem Ahmad , Wan Hong , Teh Muy-Teck
Published: March 2024

Abstract
Stem cells are permanent residents of tissues and thought to be targets of cancer initiation. The frequent, and often early, upregulation of the FOXM1 transcription factor in the majority of human cancers suggests that it may participate in the initiation of human tumorigenesis. However, this hypothesis has not been tested. Herein, we show that targeting the ectopic expression of FOXM1 to the highly clonogenic cells of primary human keratinocytes with stem/progenitor cell properties, but not to differentiating cells, caused clonal expansion in vitro. We show, using a functional three-dimensional organotypic epithelial tissue regeneration system, that ectopic FOXM1 expression perturbed epithelial differentiation generating a hyperproliferative phenotype reminiscent of that seen in human epithelial hyperplasia. Furthermore, transcriptional expression analysis of a panel of 28 epithelial differentiation-specific genes reveals a role for FOXM1 in the suppression of epithelial differentiation. This study provides the first evidence that FOXM1 participates in an early oncogenic pathway that predisposes cells to tumorigenesis by expanding the stem/progenitor compartment and deregulating subsequent keratinocyte terminal differentiation. This finding reveals an important window of susceptibility to oncogenic signals in epithelial stem/progenitor cells prior to differentiation, and may provide a significant benefit to the design of cancer therapeutic interventions that target oncogenesis at its earliest incipient stage. Cancer Res; 70(22); 9515–26. ©2010 AACR.
Data from Preventing the Activation or Cycling of the Rap1 GTPase Alters Adhesion and Cytoskeletal Dynamics and Blocks Metastatic Melanoma Cell Extravasation into the Lungs
Authors: Freeman Spencer A. , McLeod Sarah J. , Dukowski Janet , Austin Pamela , Lee Crystal C.Y. , Millen-Martin Brandie , Kubes Paul , McCafferty Donna-Marie , Gold Michael R. , Roskelley Calvin D.
Published: March 2024

Abstract
The Rap1 GTPase is a master regulator of cell adhesion, polarity, and migration. We show that both blocking Rap1 activation and expressing a constitutively active form of Rap1 reduced the ability of B16F1 melanoma cells to extravasate from the microvasculature and form metastatic lesions in the lungs. This correlated with a decreased ability of the tumor cells to undergo transendothelial migration (TEM) in vitro and form dynamic, F-actin–rich pseudopodia that penetrate capillary endothelial walls in vivo. Using multiple tumor cell lines, we show that the inability to form these membrane protrusions, which likely promote TEM and extravasation, can be explained by altered adhesion dynamics and impaired cell polarization that result when Rap1 activation or cycling is perturbed. Thus, targeting Rap1 could be a useful approach for reducing the metastatic dissemination of tumor cells that undergo active TEM. Cancer Res; 70(11); 4590–601. ©2010 AACR.
Data from ERBB Receptor Activation Is Required for Profibrotic Responses to Transforming Growth Factor β
Authors: Andrianifahanana Mahefatiana , Wilkes Mark C. , Repellin Claire E. , Edens Maryanne , Kottom Theodore J. , Rahimi Rod A. , Leof Edward B.
Published: March 2024

Abstract
Engagement of the transforming growth factor-β (TGF-β) receptor complex activates multiple signaling pathways that play crucial roles in both health and disease. TGF-β is a key regulator of fibrogenesis and cancer-associated desmoplasia; however, its exact mode of action in these pathologic processes has remained poorly defined. Here, we report a novel mechanism whereby signaling via members of the ERBB or epidermal growth factor family of receptors serves as a central requirement for the biological responses of fibroblasts to TGF-β. We show that TGF-β triggers upregulation of ERBB ligands and activation of cognate receptors via the canonical SMAD pathway in fibroblasts. Interestingly, activation of ERBB is commonly observed in a subset of fibroblast but not epithelial cells from different species, indicating cell type specificity. Moreover, using genetic and pharmacologic approaches, we show that ERBB activation by TGF-β is essential for the induction of fibroblast cell morphologic transformation and anchorage-independent growth. Together, these results uncover important aspects of TGF-β signaling that highlight the role of ERBB ligands/receptors as critical mediators in fibroblast responses to this pleiotropic cytokine. Cancer Res; 70(19); 7421–30. ©2010 AACR.
Data from Cell Selection as Driving Force in Lung and Colon Carcinogenesis
Authors: Schöllnberger Helmut , Beerenwinkel Niko , Hoogenveen Rudolf , Vineis Paolo
Published: March 2024

Abstract
Carcinogenesis is the result of mutations and subsequent clonal expansions of mutated, selectively advantageous cells. To investigate the relative contributions of mutation versus cell selection in tumorigenesis, we compared two mathematical models of carcinogenesis in two different cancer types: lung and colon. One approach is based on a population genetics model, the Wright-Fisher process, whereas the other approach is the two-stage clonal expansion model. We compared the dynamics of tumorigenesis predicted by the two models in terms of the time period until the first malignant cell appears, which will subsequently form a tumor. The mean waiting time to cancer has been calculated approximately for the evolutionary colon cancer model. Here, we derive new analytic approximations to the median waiting time for the two-stage lung cancer model and for a multistage approximation to the Wright-Fisher process. Both equations show that the waiting time to cancer is dominated by the selective advantage per mutation and the net clonal expansion rate, respectively, whereas the mutation rate has less effect. Our comparisons support the idea that the main driving force in lung and colon carcinogenesis is Darwinian cell selection. Cancer Res; 70(17); 6797–803. ©2010 AACR.
Data from CD4+ T-Cell Help in the Tumor Milieu Is Required for Recruitment and Cytolytic Function of CD8+ T Lymphocytes
Authors: Bos Rinke , Sherman Linda A.
Published: March 2024

Abstract
CD4 help for CD8+ T lymphocytes prevents tolerance and promotes the survival of effector and memory CD8+ T cells. Here, we describe additional helper functions that require CD4+ T cells within the tumor environment. CD8+ T-cell recruitment, proliferation, and effector function within the tumor were greatly enhanced by tumor-specific CD4+ T cells. Recruitment of CD8+ T cells was accelerated by IFN-γ–dependent production of chemokines. Production of interleukin-2 by tumor resident CD4+ T cells enhanced CD8+ T-cell proliferation and upregulated expression of granzyme B. These results highlight a novel role for tumor-specific CD4+ T cells in promoting CD8+ T-cell recruitment and cytolytic function, two previously unappreciated aspects of tumor-specific CD4 help. Cancer Res; 70(21); 8368–77. ©2010 AACR.
Data from Xg Expression in Ewing's Sarcoma Is of Prognostic Value and Contributes to Tumor Invasiveness
Authors: Meynet Ophélie , Scotlandi Katia , Pradelli Emmanuelle , Manara Maria C. , Colombo Mario P. , Schmid-Antomarchi Heidy , Picci Piero , Bernard Alain , Bernard Ghislaine
Published: March 2024

Abstract
Ewing's sarcoma (EWS) is an aggressive tumor of children and young adults that requires intensive treatment. The search for new prognostic factors is very important to choose the most appropriate therapy and to better understand the biology of the disease for the development of new therapeutic tools. We found that Xg, a thus far poorly described molecule and member of the CD99 family, is expressed in EWS cell lines and EWS primary tumors. Immunohistochemical analysis confirmed the expression of Xg in 24% of patients. We found that Xg expression in EWS defines a subgroup of patients with worse prognosis compared with those with Xg-negative localized tumors, indicating a clinical relevance of Xg expression in EWS. Forced expression of Xg in an EWS cell line upregulated cell migration and invasion in vitro. Furthermore, knockdown of Xg expression with specific short hairpin RNA significantly reduced migration and invasion of EWS cells. Consistent with these data, in vivo xenotransplant studies in nude mice revealed that Xg expression increased the incidence and the number of metastases of EWS cells. Thus, Xg expression is associated with lower overall survival in EWS patients with localized tumors and is implicated in metastasis. Cancer Res; 70(9); 3730–8. ©2010 AACR.
Data from Combined Delivery and Magnetic Resonance Imaging of Neural Cell Adhesion Molecule–Targeted Doxorubicin-Containing Liposomes in Experimentally Induced Kaposi's Sarcoma
Authors: Grange Cristina , Geninatti-Crich Simonetta , Esposito Giovanna , Alberti Diego , Tei Lorenzo , Bussolati Benedetta , Aime Silvio , Camussi Giovanni
Published: March 2024

Abstract
Specific targeting of tumors by combined delivery of drugs and of imaging agents represents an attractive strategy for treatment of cancer. The aim of the present study was to investigate whether neural cell adhesion molecule (NCAM)–targeted liposomes may enhance drug delivery and allow magnetic resonance imaging (MRI) in a severe combined immunodeficient mouse model of NCAM-positive Kaposi's sarcoma. NCAM-binding peptide–coated liposomes loaded with both doxorubicin and a lipophilic gadolinium (Gd) derivative were generated. NCAM-targeted liposomes induced an enhanced in vitro doxorubicin internalization within Kaposi's cells as detected by MRI with respect to untargeted polyethylene glycol liposomes. Internalization resulted in enhanced apoptosis. In vivo weekly administration of NCAM-targeted liposomes containing 5 mg/kg doxorubicin for 4 consecutive weeks induced a significant reduction of tumor mass and vascularization and enhanced cell necrosis and apoptosis with respect to untargeted liposomes. These effects were associated with an enhanced concentration of doxorubicin within the tumor and a reduced systemic toxicity of doxorubicin. By electron microscopy, NCAM-targeted liposomes were detected mainly within tumor cells whereas the untargeted liposomes were mainly accumulated in the extracellular space. Gd-labeled liposomes allowed the MRI visualization of drug delivery in the tumor region. The intensity of MRI signal was partially hampered by the “quenching” of the attainable relaxation enhancement on endosomal entrapment of the Gd-labeled liposomes. In conclusion, targeting NCAM may be a suitable strategy for specific drug delivery and imaging by liposomes in NCAM-expressing tumors. Moreover, treatment with NCAM-targeted liposomes showed enhanced therapeutic effect and reduced toxicity with respect to untargeted liposomes. Cancer Res; 70(6); 2180–90
Data from A New Paradigm for Aptamer Therapeutic AS1411 Action: Uptake by Macropinocytosis and Its Stimulation by a Nucleolin-Dependent Mechanism
Authors: Reyes-Reyes E. Merit , Teng Yun , Bates Paula J.
Published: March 2024

Abstract
AS1411 is a first-in-class anticancer agent, currently in phase II clinical trials. It is a quadruplex-forming oligodeoxynucleotide that binds to nucleolin as an aptamer, but its mechanism of action is not completely understood. Mechanistic insights could lead to clinically useful markers for AS1411 response and to novel targeted therapies. Previously, we proposed a model where cell surface nucleolin serves as the receptor for AS1411, leading to selective uptake in cancer cells. Here, we compare uptake of fluorophore-labeled AS1411 (FL-AS1411) in DU145 prostate cancer cells (sensitive to AS1411) and Hs27 nonmalignant skin fibroblasts (resistant to AS1411). Uptake of FL-AS1411 occurred by endocytosis in both cell types and was much more efficient than an inactive, nonquadruplex oligonucleotide. Unexpectedly, uptake of FL-AS1411 was lower in cancer cells compared with Hs27 cells. However, the mechanism of uptake was different, occurring by macropinocytosis in cancer cells, but by a nonmacropinocytic pathway in Hs27 cells. Additionally, treatment of various cancer cells with AS1411 caused hyperstimulation of macropinocytosis, provoking an increase in its own uptake, whereas no stimulation was observed for nonmalignant cells. Nucleolin was not required for initial FL-AS1411 uptake in DU145 cells but was necessary for induced macropinocytosis and FL-AS1411 uptake at later times. Our results are inconsistent with the previous mechanistic model but confirm that nucleolin plays a role in mediating AS1411 effects. The data suggest a new model for AS1411 action as well as a new role for nucleolin in stimulating macropinocytosis, a process with potential applications in drug delivery. Cancer Res; 70(21); 8617–29. ©2010 AACR.
Data from Jun Proteins Are Starvation-Regulated Inhibitors of Autophagy
Authors: Yogev Orli , Goldberg Rachel , Anzi Shira , Yogev Ohad , Shaulian Eitan
Published: March 2024

Abstract
The growing number of biological functions affected by autophagy ascribes a special significance to identification of factors regulating it. The activator protein-1 (AP-1) transcription factors are involved in most aspects of cellular proliferation, death, or survival, yet no information regarding their involvement in autophagy is available. Here, we show that the AP-1 proteins JunB and c-Jun, but not JunD, c-Fos, or Fra-1, inhibit autophagy. JunB inhibits autophagy induced by starvation, overexpression of a short form of ARF (smARF), a potent inducer of autophagy, or even after rapamycin treatment. In agreement, acute repression of JunB expression, by JunB knockdown, potently induces autophagy. As expected from autophagy-inhibiting proteins, Jun B and c-Jun expression is reduced by starvation. Decrease in JunB mRNA expression and posttranscriptional events downregulate JunB protein expression after starvation. The inhibition of autophagy by JunB is not mediated by mammalian target of rapamycin (mTOR) regulation, as it occurs also in the absence of mTOR activity, and autophagy induced by JunB knockdown is not correlated with changes in mTOR activity. Nevertheless, the transcriptional activities of c-Jun and JunB are required for autophagy inhibition, and JunB incapable of heterodimerizing is a less effective inhibitor of autophagy. Most importantly, inhibition of autophagy in starved HeLa cells by JunB enhances apoptotic cell death. We suggest that JunB and c-Jun are regulators of autophagy whose expression responds to autophagy-inducing signals. Cancer Res; 70(6); 2318–27
Data from Identification of Breast Tumor Mutations in BRCA1 That Abolish Its Function in Homologous DNA Recombination
Authors: Ransburgh Derek J.R. , Chiba Natsuko , Ishioka Chikashi , Toland Amanda Ewart , Parvin Jeffrey D.
Published: March 2024

Abstract
Effects of breast cancer–associated gene 1 (BRCA1) missense mutations on the function of BRCA1 protein in DNA recombination have been little studied. In this report, we adapted a homology-directed recombination (HDR) assay to analyze the effects of BRCA1 mutations on this function. Using a HeLa-derived cell line with a genomically integrated recombination substrate, we expressed an endonuclease creating a double-stranded break in the substrate that the HDR assay scores by generation of green fluorescent protein–positive cells. By combining RNA interference (RNAi) that targets cellular BRCA1 mRNA with expression of RNAi-resistant BRCA1 mutants, we could effectively substitute selected point mutants to test these in the cellular recombination assay. We found that ∼300 residues at both termini of the BRCA1 protein were essential for HDR. Whereas some mutations analyzed were neutral, mutations that altered any zinc-coordinating residue or generated M18T and T37R alterations were defective for recombination. This study established a robust assay system to analyze the function of BRCA1 in regulating homologous recombination, which is critical for its tumor suppressor function. Cancer Res; 70(3); 988–95
Data from The Chemokine Receptor CXCR7 Is Highly Expressed in Human Glioma Cells and Mediates Antiapoptotic Effects
Authors: Hattermann Kirsten , Held-Feindt Janka , Lucius Ralph , Müerköster Susanne Sebens , Penfold Mark E.T. , Schall Thomas J. , Mentlein Rolf
Published: March 2024

Abstract
The chemokine CXCL12/stromal cell–derived factor-1 and its receptor CXCR4 play a major role in tumor invasion, proliferation, and metastasis. Recently, CXCR7 was identified as a novel, alternate receptor for CXCL12 and CXCL11/I-TAC. Because both chemokines are expressed abundantly in human astrocytomas and glioblastomas, we investigated the occurrence and function of both receptors in astroglial tumors. In situ, CXCR7 is highly expressed on tumor endothelial, microglial, and glioma cells whereas CXCR4 has a much more restricted localization; CXCL12 is often colocalized with CXCR7. CXCR7 transcription in tumor homogenates increased with malignancy. In vitro, CXCR7 was highly expressed in all glioma cell lines investigated whereas CXCR4 was only scarcely transcribed on one of eight lines. In contrast, a tumor stem-like cell line preferentially expressed CXCR4 which diminished upon differentiation, whereas CXCR7 increased drastically. Stimulation of CXCR7-positive glioma cells (CXCR4- and CXCR3-negative) by CXCL12 induced transient phosphorylation of extracellular signal-regulated kinases Erk1/2, indicating that the receptor is functionally active. The phosphoinositide-specific phospholipase C inhibitor U73122 effectively inhibited Erk activation and suggests that the mitogen-activated protein kinase pathway is activated indirectly. Whereas proliferation and migration were little influenced, chemokine stimulation prevented camptothecin- and temozolomide-induced apoptosis. The selective CXCR7 antagonist CCX733 reduced the antiapoptotic effects of CXCL12 as shown by nuclear (Nicoletti) staining, caspase-3/7 activity assays, and cleavage of poly(ADP-ribose) polymerase-1. Thus, CXCR7 is a functional receptor for CXCL12 in astrocytomas/glioblastomas and mediates resistance to drug-induced apoptosis. Whereas CXCR7 is found on “differentiated” glioma cells, the alternate receptor CXCR4 is also localized on glioma stem-like cells. Cancer Res; 70(8); 3299–308. ©2010 AACR.