bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Novel Oral mTORC1/2 Inhibitor TAK-228 Has Synergistic Antitumor Effects When Combined with Paclitaxel or PI3Kα Inhibitor TAK-117 in Preclinical Bladder Cancer Models
Authors: Hernández-Prat Anna , Rodriguez-Vida Alejo , Juanpere-Rodero Nuria , Arpi Oriol , Menéndez Silvia , Soria-Jiménez Luis , Martínez Alejandro , Iarchouk Natalia , Rojo Federico , Albanell Joan , Brake Rachael , Rovira Ana , Bellmunt Joaquim
Published: April 2023

Abstract
Advanced bladder cancer is associated with a poor prognosis and limited treatment options. The PI3K/AKT/mTOR pathway is frequently activated in this disease and can be a potential therapeutic target for treatment intervention. We studied the antitumor efficacy of a new targeted therapy, TAK-228 (oral mTORC1/2 inhibitor), in preclinical models of bladder cancer. We evaluated the effects of TAK-228 in combination with a PI3Kα inhibitor (TAK-117) or with chemotherapy (paclitaxel). We used six bladder cancer cell lines and in vivo xenografts models. TAK-228 strongly inhibited cell proliferation in vitro, and reduced tumor growth and angiogenesis in vivo. Three possible biomarkers of response to TAK-228 (basal levels of 4E-BP1, p-4E-BP1/4E-BP1 ratio, or eIF4E/4E-BP1 ratio) were identified. The combination of TAK-228 and TAK-117 had synergistic effects in vitro and in vivo. Furthermore, TAK-228 demonstrated greater efficiency when combined with paclitaxel. TAK-228 also showed ex vivo activity in tumor tissue from patients with treatment-naïve bladder cancer. TAK-228 is a promising investigational agent that induces a strong effect on cell proliferation, tumor growth, and angiogenesis in bladder cancer models. High synergistic effects were observed with TAK-228 combined with a PI3K inhibitor or with chemotherapy. These results are currently being investigated in a clinic trial of TAK-228 plus paclitaxel in patients with metastatic bladder cancer (NCT03745911).
Implications:
Strong synergistic effects were observed when combining TAK-228 with TAK-117 (a PI3Kα inhibitor) or with paclitaxel chemotherapy. A phase II study at our institution is currently evaluating the efficacy of TAK-228 combined with paclitaxel in patients with metastatic bladder cancer.
Data from Circular RNA ciRS-7 Maintains Metastatic Phenotypes as a ceRNA of miR-1299 to Target MMPs
Authors: Sang Meixiang , Meng Lingjiao , Liu Sihua , Ding Pingan , Chang Sheng , Ju Yingchao , Liu Fei , Gu Lina , Lian Yishui , Geng Cuizhi
Published: April 2023

Abstract
Circular RNA ciRS-7 has been reported to act as a competing endogenous RNA (ceRNA) of the miRNA miR-7, resulting in reduced miR-7 activity and increased miR-7–targeted transcripts. However, it is unknown if ciRS-7 harbors other miRNAs with regulatory roles in triple-negative breast cancer (TNBC). The present study determined that the expression of ciRS-7 in TNBC clinical specimens and representative cells is significantly higher than other breast cancer subtypes. Functionally, downregulation of ciRS-7 inhibited cell migration and invasion of TNBC cells. Knockdown of ciRS-7 expression also inhibited the liver and lung metastasis of TNBC cells in vivo. Mechanistic studies revealed that ciRS-7 contains 20 miR-1299–binding sites and functions as a ceRNA of miR-1299 in TNBC cells. High expression of ciRS-7 maintains the high migration and invasion properties of TNBC cells by acting as a ceRNA of miR-1299 to enhance the expression of matrix metalloproteinases family members (MMP).

Implications: Circular RNA ciRS-7 is highly expressed in TNBC tumor specimens and cells, and its downregulation inhibits cell migration and invasion of TNBC cells in vitro and in vivo. In addition, ciRS-7 functions as a ceRNA of miR-1299 to enhance the expression of MMPs, which maintains the high migration and invasion properties of TNBC cells. Mol Cancer Res; 16(11); 1665–75. ©2018 AACR.
Data from Chemokine Signaling Facilitates Early-Stage Breast Cancer Survival and Invasion through Fibroblast-Dependent Mechanisms
Authors: Brummer Gage , Acevedo Diana S. , Hu Qingting , Portsche Mike , Fang Wei Bin , Yao Min , Zinda Brandon , Myers Megan , Alvarez Nehemiah , Fields Patrick , Hong Yan , Behbod Fariba , Cheng Nikki
Published: April 2023

Abstract
Ductal carcinoma in situ (DCIS) is the most common form of breast cancer, with 50,000 cases diagnosed every year in the United States. Overtreatment and undertreatment remain significant clinical challenges in patient care. Identifying key mechanisms associated with DCIS progression could uncover new biomarkers to better predict patient prognosis and improve guided treatment. Chemokines are small soluble molecules that regulate cellular homing through molecular gradients. CCL2-mediated recruitment of CCR2+ macrophages are a well-established mechanism for metastatic progression. Although the CCL2/CCR2 pathway is a therapeutic target of interest, little is known about the role of CCR2 expression in breast cancer. Here, using a mammary intraductal injection (MIND) model to mimic DCIS formation, the role of CCR2 was explored in minimally invasive SUM225 and highly invasive DCIS.com breast cancer cells. CCR2 overexpression increased SUM225 breast cancer survival and invasion associated with accumulation of CCL2 expressing fibroblasts. CCR2-deficient DCIS.com breast cancer cells formed fewer invasive lesions with fewer CCL2+ fibroblasts. Cografting CCL2-deficient fibroblasts with DCIS.com breast cancer cells in the subrenal capsule model inhibited tumor invasion and survival associated with decreased expression of aldehyde dehydrogenase (ALDH1), a proinvasive factor, and decreased expression of HTRA2, a proapoptotic serine protease. Through data mining analysis, high expression of CCR2 and ALDH1 and low HTRA2 expression were correlated with poor prognosis of breast cancer patients.

Implications: This study demonstrates that CCR2 overexpression in breast cancer drives early-stage breast cancer progression through stromal-dependent expression of CCL2 with important insight into prognosis and treatment of DCIS. Mol Cancer Res; 16(2); 296–308. ©2017 AACR.
Data from Ubiquitin-Specific Protease 3 Promotes Glioblastoma Cell Invasion and Epithelial–Mesenchymal Transition via Stabilizing Snail
Authors: Fan Ligang , Chen Zhengxin , Wu Xiaoting , Cai Xiaomin , Feng Shuang , Lu Jiacheng , Wang Huibo , Liu Ning
Published: April 2023

Abstract
Epithelial–mesenchymal transition (EMT) represents one of the most important events in the invasion of glioblastomas (GBM); therefore, better understanding of mechanisms that govern EMT is crucial for the treatment of GBMs. In this study, we report that the deubiquitinase ubiquitin-specific protease 3 (USP3) is significantly upregulated in GBMs and correlates with a shorter median overall and relapse-free survival. Silencing of USP3 attenuates the migration and invasion abilities of GBM cells in vitro and tumor growth in an orthotopic xenograft mouse model. Mechanistically, we identify USP3 as a bona fide deubiquitinase for Snail, a master transcription factor that promotes EMT, in GBM cells. USP3 interacts directly with Snail and stabilizes Snail via deubiquitination. Ectopic expression of Snail could largely rescue the inhibitory effects of USP3 depletion on migration, invasion, and tumor growth of GBM cells. In addition, we found that USP3 strongly correlates with Snail expression in primary human GBM samples. Overall, our findings reveal a critical USP3–Snail signaling axis in EMT and invasion, and provide an effective therapeutic approach against GBM.
Implications:
Our study establishes USP3-mediated Snail stabilization as an important mechanism underlying GBM invasion and progression, and provides a rationale for potential therapeutic interventions in the treatment of GBM.
Data from PDCD4 Is an Androgen-Repressed Tumor Suppressor that Regulates Prostate Cancer Growth and Castration Resistance
Authors: Zennami Kenji , Choi Su Mi , Liao Ross , Li Ying , Dinalankara Wikum , Marchionni Luigi , Rafiqi Fatema H. , Kurozumi Akira , Hatano Koji , Lupold Shawn E.
Published: April 2023

Abstract
Androgen receptor (AR) transcriptional activity contributes to prostate cancer development and castration resistance. The growth and survival pathways driven by AR remain incompletely defined. Here, we found PDCD4 to be a new target of AR signaling and a potent regulator of prostate cancer cell growth, survival, and castration resistance. The 3′ untranslated region of PDCD4 is directly targeted by the androgen-induced miRNA, miR-21. Androgen treatment suppressed PDCD4 expression in a dose responsive and miR-21–dependent manner. Correspondingly, AR inhibition dose-responsively induced PDCD4 expression. Using data from prostate cancer tissue samples in The Cancer Genome Atlas (TCGA), we found a significant and inverse correlation between miR-21 and PDCD4 mRNA and protein levels. Higher Gleason grade tumors exhibited significantly higher levels of miR-21 and significantly lower levels of PDCD4 mRNA and protein. PDCD4 knockdown enhanced androgen-dependent cell proliferation and cell-cycle progression, inhibited apoptosis, and was sufficient to drive androgen-independent growth. On the other hand, PDCD4 overexpression inhibited miR-21–mediated growth and androgen independence. The stable knockdown of PDCD4 in androgen-dependent prostate cancer cells enhanced subcutaneous tumor take rate in vivo, accelerated tumor growth, and was sufficient for castration-resistant tumor growth.
Implications:
This study provides the first evidence that PDCD4 is an androgen-suppressed protein capable of regulating prostate cancer cell proliferation, apoptosis, and castration resistance. These results uncover miR-21 and PDCD4-regulated pathways as potential new targets for castration-resistant prostate cancer.
Data from Identification of De Novo Enhancers Activated by TGFβ to Drive Expression of CDKN2A and B in HeLa Cells
Authors: Liu Yen-Ting , Xu Lin , Bennett Lynda , Hooks Jared C. , Liu Jing , Zhou Qinbo , Liem Priscilla , Zheng Yanbin , Skapek Stephen X.
Published: April 2023

Abstract
Disruption of the CDKN2A (INK4A/ARF) and B (INK4B) genes, which encode three function-independent tumor suppressors, is one of the most common events in human cancer. Because their relative importance in tumor prevention appears to be species- and context-specific, studying their regulation can shed light on mechanisms by which they are bypassed in malignant transformation. We previously unveiled a new pathway in which TGFβ selectively induces Arf at mouse Cdkn2a in eye development and cultured fibroblasts. As TGFβ signaling is often derailed in cancer development or progression, we investigated its control of CDKN2A/B in human cancer. Computational analyses of sequencing and array data from nearly 11,000 patients with cancer in TCGA showed discordant expression of ARF and INK4A in most cancer subtypes, with gene copy-number loss and promoter methylation involved in only a subset. Using HeLa cells as a model, we found that exogenous TGFβ induced ARF mRNA and protein, and ARF knockdown limited TGFβ-mediated growth suppression. TGFβ-mediated ARF mRNA induction required SMAD2/3, p38MAPK, and SP1, and ARF mRNA was induced without added RNAPII recruitment. Chromatin immunoprecipitation unveiled a remote enhancer element engaged by TGFβ by a mechanism that partially depended on p38MAPK. CRISPR-based editing of this enhancer limited induction of ARF and INK4B by TGFβ, but not by oncogenic RAS.
Implications:
Our findings reveal new molecular mechanisms by which CDKN2A/B regulation is coupled to external cues, and those findings represent entry points to further explore pharmacologic strategies to restore their expression in cancer.
Data from TRPM7 Regulates AKT/FOXO1–Dependent Tumor Growth and Is an Independent Prognostic Indicator in Renal Cell Carcinoma
Authors: Zhao Zhijian , Zhang Mengping , Duan Xiaolu , Chen Yiwen , Li Ermao , Luo Lianmin , Wu Wenqi , Peng Zhenwei , Qiu Huijuan , Zeng Guohua
Published: April 2023

Abstract
Transient receptor potential melastatin 7 (TRPM7) is important for the tumorigenesis and progression of several cancers. However, little is known about TRPM7 expression and its clinical significance in clear cell renal cell carcinoma (ccRCC). The expression dynamics of TRPM7 was examined in a clinical cohort of RCC specimens by qPCR, immunoblotting, and IHC staining. A series of in vitro and in vivo assays were performed to elucidate the function of TRPM7 in RCC and the underlying mechanisms. For the first time, results demonstrate that TRPM7 expression is markedly higher in RCC cell lines and clinical samples and had a positive correlation with T status, tumor size, and poor patients' overall survival and progression-free survival. Preclinical studies using multiple RCC cells and a mouse model indicate that TRPM7 promotes cell proliferation and colony formation in vitro and tumor growth in vivo. Mechanistically, TRPM7 promotes AKT phosphorylation, leading to repression of the FOXO1 expression and transcriptional activity. Moreover, luciferase reporter assays demonstrate that miR-129-3p directly targets the 3′-UTR of TRPM7 and acts as a negative regulator of TRPM7. These findings reveal an important role for TRPM7 in the regulation of RCC growth and represent a novel prognostic biomarker for this disease.

Implications: TRPM7 is an independent prognostic indicator in RCC, and targeting the TRPM7 signaling pathway may be a novel therapeutic approach for the treatment of RCC. Mol Cancer Res; 16(6); 1013–23. ©2018 AACR.
Data from PTPN11 Plays Oncogenic Roles and Is a Therapeutic Target for BRAF Wild-Type Melanomas
Authors: Hill Kristen S. , Roberts Evan R. , Wang Xue , Marin Ellen , Park Taeeun D. , Son Sorany , Ren Yuan , Fang Bin , Yoder Sean , Kim Sungjune , Wan Lixin , Sarnaik Amod A. , Koomen John M. , Messina Jane L. , Teer Jamie K. , Kim Youngchul , Wu Jie , Chalfant Charles E. , Kim Minjung
Published: April 2023

Abstract
Melanoma is one of the most highly mutated cancer types. To identify functional drivers of melanoma, we searched for cross-species conserved mutations utilizing a mouse melanoma model driven by loss of PTEN and CDKN2A, and identified mutations in Kras, Erbb3, and Ptpn11. PTPN11 encodes the SHP2 protein tyrosine phosphatase that activates the RAS/RAF/MAPK pathway. Although PTPN11 is an oncogene in leukemia, lung, and breast cancers, its roles in melanoma are not clear. In this study, we found that PTPN11 is frequently activated in human melanoma specimens and cell lines and is required for full RAS/RAF/MAPK signaling activation in BRAF wild-type (either NRAS mutant or wild-type) melanoma cells. PTPN11 played oncogenic roles in melanoma by driving anchorage-independent colony formation and tumor growth. In Pten- and Cdkn2a-null mice, tet-inducible and melanocyte-specific PTPN11E76K expression significantly enhanced melanoma tumorigenesis. Melanoma cells derived from this mouse model showed doxycycline-dependent tumor growth in nude mice. Silencing PTPN11E76K expression by doxycycline withdrawal caused regression of established tumors by induction of apoptosis and senescence, and suppression of proliferation. Moreover, the PTPN11 inhibitor (SHP099) also caused regression of NRASQ61K-mutant melanoma. Using a quantitative tyrosine phosphoproteomics approach, we identified GSK3α/β as one of the key substrates that were differentially tyrosine-phosphorylated in these experiments modulating PTPN11. This study demonstrates that PTPN11 plays oncogenic roles in melanoma and regulates RAS and GSK3β signaling pathways.
Implications:
This study identifies PTPN11 as an oncogenic driver and a novel and actionable therapeutic target for BRAF wild-type melanoma.
Data from Capping Protein Regulator and Myosin 1 Linker 3 Is Required for Tumor Metastasis
Authors: Wang Huan , Wang Chao , Peng Guang , Yu Doudou , Cui Xin-Gang , Sun Ying-Hao , Ma Xiaojing
Published: April 2023

Abstract
Metastasis accounts for 90% of deaths caused by solid tumors, but the multitude of mechanisms underlying tumor metastasis remains poorly understood. CARMIL1 and 2 proteins are capping protein (CP) interactants and multidomain regulators of actin-based mobility. However, CARMIL3′s function has not been explored. Through bioinformatic metadata analysis, we find that high CARMIL3 expression correlates with poor survival of patients with breast and prostate cancer. Functional studies in murine and xenograft tumor models by targeted diminution of CARMIL3 expression or forced expression demonstrate that CARMIL3 is vitally important for tumor metastasis, especially for metastatic colonization. Consistent with a predominantly cell-intrinsic mode of action, CARMIL3 is also crucial for tumor cell migration and invasion in vitro. Coimmunoprecipitation coupled with mass spectrometric analyses identifies a group of CARMIL3-interacting proteins, including capping protein, that are involved in actin cytoskeletal organization, which is required for cell polarization and focal adhesion formation. Moreover, molecular pathway enrichment analysis reveals that lack of CARMIL3 leads to loss of cell adhesions and low CARMIL3 expression in breast cancer patient specimens is implicated in epithelial–mesenchymal transition. We also find that CARMIL3 sustains adherens junction between tumor cells. This is accomplished by CARMIL3 maintaining E-cadherin transcription downstream of HDACs through inhibiting ZEB2 protein level, also via protecting β-catenin from ubiquitination-mediated degradation initiated by the destruction complex.
Implications:
This study uncovers CARMIL3 as a novel and critical regulator of metastatic progression of cancers and suggests therapeutic potentials to target CARMIL3.
Data from SINE Retrotransposons Cause Epigenetic Reprogramming of Adjacent Gene Promoters
Authors: Estécio Marcos R.H. , Gallegos Juan , Dekmezian Mhair , Lu Yue , Liang Shoudan , Issa Jean-Pierre J.
Published: April 2023

Abstract
Almost half of the human genome and as much as 40% of the mouse genome is composed of repetitive DNA sequences. The majority of these repeats are retrotransposons of the SINE and LINE families, and such repeats are generally repressed by epigenetic mechanisms. It has been proposed that these elements can act as methylation centers from which DNA methylation spreads into gene promoters in cancer. Contradictory to a methylation center function, we have found that retrotransposons are enriched near promoter CpG islands that stay methylation-free in cancer. Clearly, it is important to determine which influence, if any, these repetitive elements have on nearby gene promoters. Using an in vitro system, we confirm here that SINE B1 elements can influence the activity of downstream gene promoters, with acquisition of DNA methylation and loss of activating histone marks, thus resulting in a repressed state. SINE sequences themselves did not immediately acquire DNA methylation but were marked by H3K9me2 and H3K27me3. Moreover, our bisulfite sequencing data did not support that gain of DNA methylation in gene promoters occurred by methylation spreading from SINE B1 repeats. Genome-wide analysis of SINE repeats distribution showed that their enrichment is directly correlated with the presence of USF1, USF2, and CTCF binding, proteins with insulator function. In summary, our work supports the concept that SINE repeats interfere negatively with gene expression and that their presence near gene promoters is counter-selected, except when the promoter is protected by an insulator element. Mol Cancer Res; 10(10); 1332–42. ©2012 AACR.
Data from Interplay between Cytoplasmic and Nuclear Androgen Receptor Splice Variants Mediates Castration Resistance
Authors: Zhan Yang , Zhang Guanyi , Wang Xiaojie , Qi Yanfeng , Bai Shanshan , Li Dongying , Ma Tianfang , Sartor Oliver , Flemington Erik K. , Zhang Haitao , Lee Peng , Dong Yan
Published: April 2023

Abstract
Androgen receptor splice variants (AR-V) are implicated in resistance of prostate cancer to androgen-directed therapies. When expressed alone in cells, some AR-Vs (e.g., AR-V7) localize primarily to the nucleus, whereas others (e.g., AR-V1, AR-V4, and AR-V6) localize mainly to the cytoplasm. Significantly, the latter are often coexpressed with the nucleus-predominant AR-Vs and the full-length AR (AR-FL). An important question to be addressed is whether the cytoplasmic-localized AR-Vs play a role in castration-resistant prostate cancer (CRPC) through interaction with the nucleus-predominant AR-Vs and AR-FL. Here, it is demonstrated that AR-V1, -V4, and -V6 can dimerize with both AR-V7 and AR-FL. Consequently, AR-V7 and androgen-bound AR-FL induced nuclear localization of AR-V1, -V4, and -V6, and these variants, in turn, mitigated the ability of the antiandrogen enzalutamide to inhibit androgen-induced AR-FL nuclear localization. Interestingly, the impact of nuclear localization of AR-V4 and -V6 on AR transactivation differs from that of AR-V1. Nuclear localization leads to an increased ability of AR-V4 and -V6 to transactivate both canonical AR targets and AR-V–specific targets and to confer castration-resistant cell growth. However, although AR-V1, which lacks inherent transcriptional activity, appears to activate AR-FL in an androgen-independent manner, it significantly antagonizes AR-V7 transactivation. Together, these data demonstrate that the complex interactions among different AR-Vs and AR-FL play a significant role in castration-resistant disease.

Implications: This study suggests important consequences for clinical castration resistance due to simultaneous expression of AR-FL and AR-Vs in patient tumors and suggests that dissecting these interactions should help develop effective strategies to disrupt AR-V signaling. Mol Cancer Res; 15(1); 59–68. ©2016 AACR.
Data from Gain-of-Function Mutations in the Extracellular Domain of KIT Are Common in Canine Mast Cell Tumors
Authors: Letard Sébastien , Yang Ying , Hanssens Katia , Palmérini Fabienne , Leventhal Phillip S. , Guéry Stéphanie , Moussy Alain , Kinet Jean-Pierre , Hermine Olivier , Dubreuil Patrice
Published: April 2023

Abstract
In the current study, we examined the types and frequency of KIT mutations in mast cell tumors from 191 dogs. Sequencing of reverse transcription-PCR products revealed alterations in 50 (26.2%) of the dogs. Most mutations were in exon 11 (n = 32), and of these, most were internal tandem duplications (n = 25) between residues 571 and 590. Within exon 11, there were two hotspots for mutations at codons 555-559 and 571-590. In addition, nine dogs had mutations in exon 8 and eight had mutations in exon 9. We selected the two most common mutants and two representative exon 11 mutants for further analysis. When expressed in Ba/F3 cells, they were constitutively tyrosine phosphorylated and induced growth factor–independent cell proliferation. AG1296, a tyrosine kinase inhibitor, dose dependently inhibited both the tyrosine phosphorylation of these mutants and their induction of growth factor–independent proliferation. This study shows that activating mutations in not only exon 11 but also exons 8 and 9 are common in canine mast cell tumors. These results also show that Ba/F3 cells can be used for the direct characterization of canine KIT mutants, eliminating the need to make equivalent mutations in the mouse or human genes. (Mol Cancer Res 2008;6(7):1137–45)
Data from Cross-talk between Phospho-STAT3 and PLCγ1 Plays a Critical Role in Colorectal Tumorigenesis
Authors: Zhang Peng , Zhao Yiqing , Zhu Xiaofeng , Sedwick David , Zhang Xiaodong , Wang Zhenghe
Published: April 2023

Abstract
Hyperphosphorylation at the Y705 residue of signal transducer and activator of transcription 3 (STAT3) is implicated in tumorigenesis of leukemia and some solid tumors. However, its role in the development of colorectal cancer is not well defined. To rigorously test the impact of this phosphorylation on colorectal tumorigenesis, we engineered a STAT3 Y705F knock-in to interrupt STAT3 activity in HCT116 and RKO colorectal cancer cells. These STAT3 Y705F mutant cells fail to respond to cytokine stimulation and grow slower than parental cells. These mutant cells are also greatly diminished in their abilities to form colonies in culture, to exhibit anchorage-independent growth in soft agar, and to grow as xenografts in nude mice. These observations strongly support the premise that STAT3 Y705 phosphorylation is crucial in colorectal tumorigenesis. Although it is generally believed that STAT3 functions as a transcription factor, recent studies indicate that transcription-independent functions of STAT3 also play an important role in tumorigenesis. We show here that wild-type STAT3, but not STAT3 Y705F mutant protein, associates with phospholipase Cγ1 (PLCγ1). PLCγ1 is a central signal transducer of growth factor and cytokine signaling pathways that are involved in tumorigenesis. In STAT3 Y705F mutant colorectal cancer cells, PLCγ1 activity is reduced. Moreover, overexpression of a constitutively active form of PLCγ1 rescues the transformation defect of STAT3 Y705F mutant cells. In aggregate, our study identifies previously unknown cross-talk between STAT3 and the PLCγ signaling pathways that may play a critical role in colorectal tumorigenesis. Mol Cancer Res; 9(10); 1418–28. ©2011 AACR.
Data from Autocrine Endothelin-3/Endothelin Receptor B Signaling Maintains Cellular and Molecular Properties of Glioblastoma Stem Cells
Authors: Liu Yue , Ye Fei , Yamada Kazunari , Tso Jonathan L. , Zhang Yibei , Nguyen David H. , Dong Qinghua , Soto Horacio , Choe Jinny , Dembo Anna , Wheeler Hayley , Eskin Ascia , Schmid Ingrid , Yong William H. , Mischel Paul S. , Cloughesy Timothy F. , Kornblum Harley I. , Nelson Stanley F. , Liau Linda M. , Tso Cho-Lea
Published: April 2023

Abstract
Glioblastoma stem cells (GSC) express both radial glial cell and neural crest cell (NCC)-associated genes. We report that endothelin 3 (EDN3), an essential mitogen for NCC development and migration, is highly produced by GSCs. Serum-induced proliferative differentiation rapidly decreased EDN3 production and downregulated the expression of stemness-associated genes, and reciprocally, two glioblastoma markers, EDN1 and YKL-40 transcripts, were induced. Correspondingly, patient glioblastoma tissues express low levels of EDN3 mRNA and high levels of EDN1 and YKL-40 mRNA. Blocking EDN3/EDN receptor B (EDNRB) signaling by an EDNRB antagonist (BQ788), or EDN3 RNA interference (siRNA), leads to cell apoptosis and functional impairment of tumor sphere formation and cell spreading/migration in culture and loss of tumorigenic capacity in animals. Using exogenous EDN3 as the sole mitogen in culture does not support GSC propagation, but it can rescue GSCs from undergoing cell apoptosis. Molecular analysis by gene expression profiling revealed that most genes downregulated by EDN3/EDNRB blockade were those involved in cytoskeleton organization, pause of growth and differentiation, and DNA damage response, implicating the involvement of EDN3/EDNRB signaling in maintaining GSC migration, undifferentiation, and survival. These data suggest that autocrine EDN3/EDNRB signaling is essential for maintaining GSCs. Incorporating END3/EDNRB-targeted therapies into conventional cancer treatments may have clinical implication for the prevention of tumor recurrence. Mol Cancer Res; 9(12); 1668–85. ©2011 AACR.
Data from Cancer Cell Dependence on Unsaturated Fatty Acids Implicates Stearoyl-CoA Desaturase as a Target for Cancer Therapy
Authors: Roongta Urvashi V. , Pabalan Jonathan G. , Wang Xinyu , Ryseck Rolf-Peter , Fargnoli Joseph , Henley Benjamin J. , Yang Wen-Pin , Zhu Jun , Madireddi Malavi T. , Lawrence R. Michael , Wong Tai W. , Rupnow Brent A.
Published: April 2023

Abstract
Emerging literature suggests that metabolic pathways play an important role in the maintenance and progression of human cancers. In particular, recent studies have implicated lipid biosynthesis and desaturation as a requirement for tumor cell survival. In the studies reported here, we aimed to understand whether tumor cells require the activity of either human isoform of stearoyl-CoA-desaturase (SCD1 or SCD5) for survival. Inhibition of SCD1 by siRNA or a small molecule antagonist results in strong induction of apoptosis and growth inhibition, when tumor cells are cultured in reduced (2%) serum conditions, but has little impact on cells cultured in 10% serum. Depletion of SCD5 had minimal effects on cell growth or apoptosis. Consistent with the observed dependence on SCD1, but not SCD5, levels of SCD1 protein increased in response to decreasing serum levels. Both induction of SCD1 protein and sensitivity to growth inhibition by SCD1 inhibition could be reversed by supplementing growth media with unsaturated fatty acids, the product of the enzymatic reaction catalyzed by SCD1. Transcription profiling of cells treated with an SCD inhibitor revealed strong induction of markers of endoplasmic reticulum stress. Underscoring its importance in cancer, SCD1 protein was found to be highly expressed in a large percentage of human cancer specimens. SCD inhibition resulted in tumor growth delay in a human gastric cancer xenograft model. Altogether, these results suggest that desaturated fatty acids are required for tumor cell survival and that SCD may represent a viable target for the development of novel agents for cancer therapy. Mol Cancer Res; 9(11); 1551–61. ©2011 AACR.
Data from MicroRNA-138 Modulates DNA Damage Response by Repressing Histone H2AX Expression
Authors: Wang Yemin , Huang Jen-Wei , Li Ming , Cavenee Webster K. , Mitchell Patrick S. , Zhou Xiaofeng , Tewari Muneesh , Furnari Frank B. , Taniguchi Toshiyasu
Published: April 2023

Abstract
Precise regulation of DNA damage response is crucial for cellular survival after DNA damage, and its abrogation often results in genomic instability in cancer. Phosphorylated histone H2AX (γH2AX) forms nuclear foci at sites of DNA damage and facilitates DNA damage response and repair. MicroRNAs (miRNA) are short, nonprotein-encoding RNA molecules, which posttranscriptionally regulate gene expression by repressing translation of and/or degrading mRNA. How miRNAs modulate DNA damage response is largely unknown. In this study, we developed a cell-based screening assay using ionizing radiation (IR)-induced γH2AX foci formation in a human osteosarcoma cell line, U2OS, as the readout. By screening a library of human miRNA mimics, we identified several miRNAs that inhibited γH2AX foci formation. Among them, miR-138 directly targeted the histone H2AX 3′-untranslated region, reduced histone H2AX expression, and induced chromosomal instability after DNA damage. Overexpression of miR-138 inhibited homologous recombination and enhanced cellular sensitivity to multiple DNA-damaging agents (cisplatin, camptothecin, and IR). Reintroduction of histone H2AX in miR-138 overexpressing cells attenuated miR-138–mediated sensitization to cisplatin and camptothecin. Our study suggests that miR-138 is an important regulator of genomic stability and a potential therapeutic agent to improve the efficacy of radiotherapy and chemotherapy with DNA-damaging agents. Mol Cancer Res; 9(8); 1100–11. ©2011 AACR.
Data from Functional Analysis of Secreted Caveolin-1 in Mouse Models of Prostate Cancer Progression
Authors: Watanabe Masami , Yang Guang , Cao Guangwen , Tahir Salahaldin A. , Naruishi Koji , Tabata Ken-ichi , Fattah Elmoataz Abdel , Rajagopalan Kartik , Timme Terry L. , Park Sanghee , Kurosaka Shinji , Edamura Kohei , Tanimoto Ryuta , Demayo Francesco J. , Goltsov Alexei A. , Thompson Timothy C.
Published: April 2023

Abstract
Previously, we reported that caveolin-1 (cav-1) is overexpressed in metastatic prostate cancer and that virulent prostate cancer cells secrete biologically active cav-1. We also showed that cav-1 expression leads to prosurvival activities through maintenance of activated Akt and that cav-1 is taken up by other cav-1–negative tumor cells and/or endothelial cells, leading to stimulation of angiogenic activities through PI-3-K-Akt-eNOS signaling. To analyze the functional consequences of cav-1 overexpression on the development and progression of prostate cancer in vivo, we generated PBcav-1 transgenic mice. Adult male PBcav-1 mice showed significantly increased prostatic wet weight and higher incidence of epithelial hyperplasia compared with nontransgenic littermates. Increased immunostaining for cav-1, proliferative cell nuclear antigen, P-Akt, and reduced nuclear p27Kip1 staining occurred in PBcav-1 hyperplastic prostatic lesions. PBcav-1 mice showed increased resistance to castration-induced prostatic regression and elevated serum cav-1 levels compared with nontransgenic littermates. Intraprostatic injection of androgen-sensitive, cav-1–secreting RM-9 mouse prostate cancer cells resulted in tumors that were larger in PBcav-1 mice than in nontransgenic littermates (P = 0.04). Tail vein inoculation of RM-9 cells produced significantly more experimental lung metastases in PBcav-1 males than in nontransgenic male littermates (P = 0.001), and in cav-1+/+ mice than in cav-1−/− mice (P = 0.041). Combination treatment with surgical castration and systemic cav-1 antibody dramatically reduced the number of experimental metastases. These experimental data suggest a causal association of secreted cav-1 and prostate cancer growth and progression. (Mol Cancer Res 2009;7(9):1446–55)
Data from KIAA0101 Interacts with BRCA1 and Regulates Centrosome Number
Authors: Kais Zeina , Barsky Sanford H. , Mathsyaraja Haritha , Zha Alicia , Ransburgh Derek J.R. , He Gang , Pilarski Robert T. , Shapiro Charles L. , Huang Kun , Parvin Jeffrey D.
Published: April 2023

Abstract
To find genes and proteins that collaborate with BRCA1 or BRCA2 in the pathogenesis of breast cancer, we used an informatics approach and found a candidate BRCA interactor, KIAA0101, to function like BRCA1 in exerting a powerful control over centrosome number. The effect of KIAA0101 on centrosomes is likely direct, as its depletion does not affect the cell cycle, KIAA0101 localizes to regions coincident with the centrosomes, and KIAA0101 binds to BRCA1. We analyzed whether KIAA0101 protein is overexpressed in breast cancer tumor samples in tissue microarrays, and we found that overexpression of KIAA0101 correlated with positive Ki67 staining, a biomarker associated with increased disease severity. Furthermore, overexpression of the KIAA0101 gene in breast tumors was found to be associated with significantly decreased survival time. This study identifies KIAA0101 as a protein important for breast tumorigenesis, and as this factor has been reported as a UV repair factor, it may link the UV damage response to centrosome control. Mol Cancer Res; 9(8); 1091–9. ©2011 AACR.
Data from Mechanisms of Drug Sensitization to TRA-8, an Agonistic Death Receptor 5 Antibody, Involve Modulation of the Intrinsic Apoptotic Pathway in Human Breast Cancer Cells
Authors: Amm Hope M. , Zhou Tong , Steg Adam D. , Kuo Huichien , Li Yufeng , Buchsbaum Donald J.
Published: April 2023

Abstract
TRA-8, a monoclonal antibody to death receptor 5 induces apoptosis in various cancer cells; however, the degree of sensitivity varies from highly sensitive to resistant. We have previously shown that resistance to TRA-8 can be reversed by using chemotherapeutic agents, but the mechanism underlying this sensitization was not fully understood. Here, we examined the combination of TRA-8 with doxorubicin or bortezomib in breast cancer cells. In TRA-8–resistant BT-474 and T47D cells, both chemotherapy agents synergistically sensitized cells to TRA-8 cytotoxicity with enhanced activation of apoptosis shown by cleavage of caspases and PARP, reduced Bid, increased proapoptotic Bcl-2 proteins, and increased mitochondrial membrane depolarization. Doxorubicin or bortezomib combined with TRA-8 also reduced Bcl-XL and X-linked inhibitors of apoptosis (XIAP) in treated cells. Furthermore, targeting these proteins with pharmacologic modulators, AT-101, BH3I-2′ and AT-406, produced sensitization to TRA-8. TRA-8 combined with AT-101 or BH3I-2′, inhibitors of antiapoptotic Bcl-2 proteins, produced synergistic cytotoxicity against ZR-75-1, BT-474, and T47D cells. The IAP-targeting compound, AT-406, was synergistic with TRA-8 in BT-474 cells, and to a lesser extent T47D cells. Activation of the intrinsic apoptotic pathway was a common mechanism associated with sensitization of TRA-8–resistant breast cancer cell lines. Collectively, these studies show that the Bcl-2 and IAP families of proteins are involved in TRA-8 and chemotherapy resistance via their modulation of the intrinsic apoptotic pathway. Targeting these proteins with novel agents sensitized TRA-8–resistant breast cancer cells, suggesting this approach may represent a potent therapeutic strategy in the treatment of breast cancer. Mol Cancer Res; 9(4); 403–17. ©2011 AACR.
Data from Loss of Trop2 Promotes Carcinogenesis and Features of Epithelial to Mesenchymal Transition in Squamous Cell Carcinoma
Authors: Wang Jianbo , Zhang Kaihua , Grabowska Dorota , Li Aimin , Dong Yiyu , Day Ryan , Humphrey Peter , Lewis James , Kladney Raleigh D. , Arbeit Jeffrey M. , Weber Jason D. , Chung Christine H. , Michel Loren S.
Published: April 2023

Abstract
Trop2, an oncogenic cell surface protein under investigation as a therapeutic target, is commonly overexpressed in several epithelial tumor types yet its function in tumor biology remains relatively unexplored. To investigate the role of Trop2 in epithelial carcinogenesis, we generated Trop2−/− mice, which are viable and possess a normal lifespan. Contrary to expectations, Trop2 loss fails to suppress keratinocyte transformation. Instead, ras-transformed Trop2−/− keratinocytes preferentially pass through an epithelial to mesenchymal transition (EMT) and form tumors with spindle cell histology. Furthermore, Trop2 loss renders Arf-null mice susceptible to the formation of biphasic sarcomatoid carcinomas containing both squamous and spindle cell components upon carcinogen exposure in an otherwise skin cancer–resistant strain (C57BL/6). Immortalized keratinocytes derived from Trop2−/−Arf−/− mice exhibit enhanced proliferative and migratory capacity as well as increased activation of mitogen-activated protein kinase and Src prior to transformation. The clinical relevance of these findings was supported by studying the molecular epidemiology of Trop2 in primary head and neck squamous cell carcinomas. This analysis revealed that Trop2 mRNA levels are decreased in a subset of tumors with features of EMT, and total loss of Trop2 protein expression is observed in the spindle cell component of sarcomatoid carcinomas. Therefore, while previous studies have emphasized the potential importance of Trop2 gain of function, these results uncover a role for Trop2 loss in tumorigenesis and the mesenchymal transdifferentiation observed in a subset of squamous cell carcinomas. Mol Cancer Res; 9(12); 1686–95. ©2011 AACR.
Data from DOC45, a Novel DNA Damage–Regulated Nucleocytoplasmic ATPase That Is Overexpressed in Multiple Human Malignancies
Authors: Sun Hong , Luo Xiuquan , Montalbano JoAnne , Jin Weixin , Shi Jingxue , Sheikh M. Saeed , Huang Ying
Published: April 2023

Abstract
In this article, we report the characterization of a novel DNA damage–regulated gene, named DNA damage–regulated overexpressed in cancer 45 (DOC45). Our results indicate that DNA damage–inducing agents, including doxorubicin (adriamycin), etoposide, and ionizing and UV radiation, strongly downregulate DOC45 expression, whereas endoplasmic reticulum stress–inducing agents do not. Our results also indicate that DOC45 is overexpressed in several human malignancies, including cancers of the colon, rectum, ovary, lung, stomach, and uterus. DOC45 harbors conserved nucleotide triphosphate–binding motifs and is capable of ATP hydrolysis, findings that highlight its function as a novel ATPase. Although predominantly cytoplasmic, DOC45 exhibits a characteristic nucleocytoplasmic distribution and, on inhibition of nuclear export, predominantly accumulates in the nucleoli. These results suggest that DOC45 may shuttle between nucleus and cytoplasm to carry out its function. Our results also indicate that DOC45 expression is enhanced during oncogenic Ras-mediated transformation and that its expression is linked to phosphoinositide 3-kinase signaling pathway. Furthermore, short hairpin RNA–mediated knockdown of DOC45 in human colon cancer cells inhibits their proliferation and enhances cellular sensitivity to doxorubicin-induced cell death, suggesting that DOC45 plays an important role in cell proliferation and survival. Collectively, our results indicate that DOC45 is a novel ATPase that is linked to cellular stress response and tumorigenesis, and may also serve as a valuable tumor marker. Mol Cancer Res; 8(1); 57–66
Data from Sox7 Is an Independent Checkpoint for β-Catenin Function in Prostate and Colon Epithelial Cells
Authors: Guo Lizheng , Zhong Diansheng , Lau Stephen , Liu Xiuju , Dong Xue-Yuan , Sun Xiaodong , Yang Vincent W. , Vertino Paula M. , Moreno Carlos S. , Varma Vijay , Dong Jin-Tang , Zhou Wei
Published: April 2023

Abstract
The presence of somatic β-catenin mutations in some prostate cancers implies that aberrant WNT signaling is involved in the cancer development. Although β-catenin stability is regulated by a multicomponent destruction complex, mutational alterations of β-catenin or other components of the destruction complexes are rare in prostate tumors. Therefore, β-catenin may be regulated by another protein in the prostate. In fact, recent linkage and somatic deletion analyses in prostate cancers reveal a 1.4-Mb candidate tumor suppressor locus on 8p23.1, which includes the Sox7 gene. Here we show that Sox7 protein expression was indeed down-regulated in 47% (15 of 32) of prostate adenocarcinomas. In addition, Sox7 mRNA was down-regulated in 60% of snap-frozen tumors. This down-regulation was found to be due to tumor-specific promoter hypermethylation, which was present in 48% (10 of 21) of primary prostate tumors and 44% (11 of 25) of prostate cancer cell lines/xenografts. We discovered that Sox7 protein physically interacts with β-catenin and suppresses β-catenin–mediated transcription by depleting active β-catenin. Furthermore, in HCT116 colorectal cancer cell lines with Sox7 inactivation, ectopic Sox7 expression suppressed cell proliferation and inhibited transcription that was activated by an endogenous mutant β-catenin. Although nearly all colorectal cancers contain mutations in β-catenin or adenomatous polyposis coli/axin, epigenetic silencing of Sox7 was still observed. These data suggest that Sox7 is a tumor suppressor that functions as an independent checkpoint for β-catenin transcriptional activity. Inactivation of Sox7 could promote the development of a majority of colorectal tumors and approximately half of prostate tumors. (Mol Cancer Res 2008;6(9):1421–10)
Data from Ataxia Telangiectasia-Mutated–Dependent DNA Damage Checkpoint Functions Regulate Gene Expression in Human Fibroblasts
Authors: Zhou Tong , Chou Jeff , Zhou Yingchun , Simpson Dennis A. , Cao Feng , Bushel Pierre R. , Paules Richard S. , Kaufmann William K.
Published: April 2023

Abstract
The relationships between profiles of global gene expression and DNA damage checkpoint functions were studied in cells from patients with ataxia telangiectasia (AT). Three telomerase-expressing AT fibroblast lines displayed the expected hypersensitivity to ionizing radiation (IR) and defects in DNA damage checkpoints. Profiles of global gene expression in AT cells were determined at 2, 6, and 24 h after treatment with 1.5-Gy IR or sham treatment and were compared with those previously recognized in normal human fibroblasts. Under basal conditions, 160 genes or expressed sequence tags were differentially expressed in AT and normal fibroblasts, and these were associated by gene ontology with insulin-like growth factor binding and regulation of cell growth. On DNA damage, 1,091 gene mRNAs were changed in at least two of the three AT cell lines. When compared with the 1,811 genes changed in normal human fibroblasts after the same treatment, 715 were found in both AT and normal fibroblasts, including most genes categorized by gene ontology into cell cycle, cell growth, and DNA damage response pathways. However, the IR-induced changes in these 715 genes in AT cells usually were delayed or attenuated in comparison with normal cells. The reduced change in DNA damage response genes and the attenuated repression of cell cycle–regulated genes may account for the defects in cell cycle checkpoint function in AT cells. (Mol Cancer Res 2007;5(8):813–22)
Data from Integrative Genomic Analysis of Small-Cell Lung Carcinoma Reveals Correlates of Sensitivity to Bcl-2 Antagonists and Uncovers Novel Chromosomal Gains
Authors: Olejniczak Edward T. , Van Sant Charles , Anderson Mark G. , Wang Gang , Tahir Stephen K. , Sauter Guido , Lesniewski Rick , Semizarov Dimitri
Published: April 2023

Abstract
Cancer is a highly heterogeneous disease in terms of the genetic profile and the response to therapeutics. An early identification of a genomic marker in drug discovery may help select patients that would respond to treatment in clinical trials. Here we suggest coupling compound screening with comparative genomic hybridization analysis of the model systems for early discovery of genomic biomarkers. A Bcl-2 antagonist, ABT-737, has recently been discovered and shown to induce regression of solid tumors, but its activity is limited to a fraction of small-cell lung carcinoma (SCLC) models tested. We used comparative genomic hybridization on high-density single-nucleotide polymorphism genotyping arrays to carry out a genome-wide analysis of 23 SCLC cell lines sensitive and resistant to ABT-737. The screen revealed a number of novel recurrent gene copy number abnormalities, which were also found in an independent data set of 19 SCLC tumors and confirmed by real-time quantitative PCR. A previously unknown amplification was identified on 18q and associated with the sensitivity of SCLC cell lines to ABT-737 and another Bcl-2 antagonist. The region of gain contains Bcl-2 and NOXA, two apoptosis-related genes. Expression microarray profiling showed that the genes residing in the amplified region of 18q are also overexpressed in the sensitive lines relative to the resistant lines. Fluorescence in situ hybridization analysis of tumors revealed that Bcl-2 gain is a frequent event in SCLC. Our findings suggest that 18q21-23 copy number will be a clinically relevant predictor for sensitivity of SCLC to Bcl-2 family inhibitors. The 18q21-23 genomic marker may have a broader application in cancer because Bcl-2 is associated with apoptosis evasion and chemoresistance. (Mol Cancer Res 2007;5(4):331–39)
Data from Expression of PGK1 by Prostate Cancer Cells Induces Bone Formation
Authors: Jung Younghun , Shiozawa Yusuke , Wang Jianhua , Wang Jingcheng , Wang Zhuo , Pedersen Elisabeth A. , Lee Clara H. , Hall Christopher L. , Hogg Phillip J. , Krebsbach Paul H. , Keller Evan T. , Taichman Russell S.
Published: April 2023

Abstract
Prostate cancer (PCa) is one of the solid tumors that metastasize to the bone. Once there, the phenotype of the bone lesions is dependent upon the balance between osteoblastogenesis and osteoclastogenesis. We previously reported that overexpression of phosphoglycerate kinase 1 (PGK1) in PCa cell lines enhanced bone formation at the metastatic site in vivo. Here, the role of PGK1 in the bone formation was further explored. We show that PCa-derived PGK1 induces osteoblastic differentiation of bone marrow stromal cells. We also found that PGK1 secreted by PCa inhibits osteoclastogenesis. Finally, the expression levels of the bone-specific markers in PCa cells were higher in cells overexpressing PGK1 than controls. Together, these data suggest that PGK1 secreted by PCa regulates bone formation at the metastatic site by increasing osteoblastic activity, decreasing osteoclastic function, and expressing an osteoblastic phenotype by PCa cells. (Mol Cancer Res 2009;7(10):1595–604)