bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from PPARδ Interacts with the Hippo Coactivator YAP1 to Promote SOX9 Expression and Gastric Cancer Progression
Authors: Song Shumei , Wang Zhenning , Li Yuan , Ma Lang , Jin Jiankang , Scott Ailing W. , Xu Yan , Estrella Jeannelyn Santiano , Song Yongxi , Liu Bin , Johnson Randy L. , Ajani Jaffer A.
Published: March 2024

Abstract
Despite established functions of PPARδ in lipid metabolism and tumorigenesis, the mechanisms underlying its role in gastric cancer are undefined. Here, we demonstrate that SOX9 was dramatically induced by stably expressing PPARδ and by its agonist GW501516 in human gastric cancer cell lines. PPARδ knockdown in patient-derived gastric cancer cells dramatically reduced SOX9 expression and transcriptional activity, with corresponding decreases in invasion and tumor sphere formation. Mechanistically, PPARδ induced SOX9 transcription through direct interaction with and activation of the Hippo coactivator YAP1. PPARδ–YAP1 interaction occurred via the C-terminal domain of YAP1, and both TEAD- and PPARE-binding sites were required for SOX9 induction. Notably, CRISPR/Cas9-mediated genetic ablation of YAP1 or SOX9 abolished PPARδ-mediated oncogenic functions. Finally, expression of PPARδ, YAP1, and SOX9 were significantly correlated with each other and with poor survival in a large cohort of human gastric cancer tissues. Thus, these findings elucidate a novel mechanism by which PPARδ promotes gastric tumorigenesis through interaction with YAP1 and highlights the PPARδ/YAP1/SOX9 axis as a novel therapeutic target in human gastric cancer.
Implications:
Our discovery of a new model supports a distinct paradigm for PPARδ and a crucial oncogenic function of PPARδ in gastric cancer through convergence on YAP1/TEAD signaling. Therefore, PPARδ/YAP1/SOX9 axis could be a novel therapeutic target that can be translated into clinics.
Data from UBE2C Is Upregulated by Estrogen and Promotes Epithelial–Mesenchymal Transition via p53 in Endometrial Cancer
Authors: Liu Yan , Zhao Rong , Chi Shuqi , Zhang Wei , Xiao Chengyu , Zhou Xing , Zhao Yingchao , Wang Hongbo
Published: March 2024

Abstract
Ubiquitin-conjugating enzyme E2C (UBE2C) plays important roles in tumor progression; nevertheless, its function in endometrial cancer remains unclear. This study elucidated the impact of UBE2C on endometrial cancer and its underlying mechanism. Human endometrial cancer and normal endometrial tissues were acquired from patients at Wuhan Union Hospital and UBE2C expression was detected by Western blotting and qRT-PCR. Endometrial cancer cells were transfected with a UBE2C overexpression plasmid or UBE2C-specific short hairpin RNA (shRNA) to up- or downregulate UBE2C expression, respectively. CCK8 and transwell assays were applied to assess the effects of UBE2C on cell proliferation, migration, and invasion. We found a significant elevation of UBE2C expression in patients with endometrial cancer, and that UBE2C upregulation was associated with advanced histologic grade, FIGO stage, recurrence, and shorter overall survival. UBE2C knockdown inhibited endometrial cancer cell proliferation, migration, invasion, and epithelial–mesenchymal transition (EMT), whereas UBE2C overexpression exerted the opposite effects. UBE2C downregulation increased p53 and its downstream p21 expression, with p53 overexpression reversing the EMT-promoting effects of UBE2C. UBE2C enhanced p53 ubiquitination to facilitate its degradation in endometrial cancer cells. Estradiol (E2) induced UBE2C expression via estrogen receptor α, which binds directly to the UBE2C promoter element. Silencing of UBE2C inhibited E2-promoted migration, invasion, and EMT in vitro and in vivo.
Implications:
UBE2C-mediated tumor EMT promotion by estrogen is a novel mechanism for the progression of estrogen-induced endometrial cancer, which could offer new biomarkers for diagnosis and therapy of endometrial cancer in the future.
Data from Activation of AXL as a Preclinical Acquired Resistance Mechanism Against Osimertinib Treatment in EGFR-Mutant Non–Small Cell Lung Cancer Cells
Authors: Namba Kei , Shien Kazuhiko , Takahashi Yuta , Torigoe Hidejiro , Sato Hiroki , Yoshioka Takahiro , Takeda Tatsuaki , Kurihara Eisuke , Ogoshi Yusuke , Yamamoto Hiromasa , Soh Junichi , Tomida Shuta , Toyooka Shinichi
Published: March 2024

Abstract
Osimertinib (AZD9291) has an efficacy superior to that of standard EGFR-tyrosine kinase inhibitors for the first-line treatment of patients with EGFR-mutant advanced non–small cell lung cancer (NSCLC). However, patients treated with osimertinib eventually acquire drug resistance, and novel therapeutic strategies to overcome acquired resistance are needed. In clinical or preclinical models, several mechanisms of acquired resistance to osimertinib have been elucidated. However, the acquired resistance mechanisms when osimertinib is initially used for EGFR-mutant NSCLC remain unclear. In this study, we experimentally established acquired osimertinib-resistant cell lines from EGFR-mutant NSCLC cell lines and investigated the molecular profiles of resistant cells to uncover the mechanisms of acquired resistance. Various resistance mechanisms were identified, including the acquisition of MET amplification, EMT induction, and the upregulation of AXL. Using targeted next-generation sequencing with a multigene panel, no secondary mutations were detected in our resistant cell lines. Among three MET-amplified cell lines, one cell line was sensitive to a combination of osimertinib and crizotinib. Acquired resistance cell lines derived from H1975 harboring the T790M mutation showed AXL upregulation, and the cell growth of these cell lines was suppressed by a combination of osimertinib and cabozantinib, an inhibitor of multiple tyrosine kinases including AXL, both in vitro and in vivo. Our results suggest that AXL might be a therapeutic target for overcoming acquired resistance to osimertinib.
Implications:
Upregulation of AXL is one of the mechanisms of acquired resistance to osimertinib, and combination of osimertinib and cabozantinib might be a key treatment for overcoming osimertinib resistance.
Data from FAK Expression, Not Kinase Activity, Is a Key Mediator of Thyroid Tumorigenesis and Protumorigenic Processes
Authors: Kessler Brittelle E. , Sharma Vibha , Zhou Qiong , Jing Xia , Pike Laura A. , Kerege Anna A. , Sams Sharon B. , Schweppe Rebecca E.
Published: March 2024

Abstract
There are limited therapy options for advanced thyroid cancer, including papillary and anaplastic thyroid cancer (PTC and ATC). Focal adhesion kinase (FAK) regulates cell signaling by functioning as a scaffold and kinase. Previously, we demonstrated that FAK is overexpressed and activated in thyroid cancer cells and human PTC clinical specimens. However, it remains unclear whether patients with advanced thyroid cancer will benefit from FAK inhibition. Therefore, the dual functions of FAK in mediating protumorigenic processes and thyroid tumorigenesis were investigated. Evidence here shows that FAK expression predominantly regulates thyroid cancer cell growth, viability, and anchorage-independent growth. FAK inhibition, with PF-562,271 treatment, modestly reduced tumor volumes, while FAK depletion, through shRNA knockdown, significantly reduced tumor volumes in vivo. A role for FAK expression in tumor establishment was demonstrated in a model of PTC, where FAK knockdown tumors did not develop. FAK depletion also led to a significant decrease in overall metastatic burden. Interestingly, pretreatment with a FAK inhibitor resulted in a paradoxical increase in metastasis in a model of ATC, but decreased metastasis in a model of PTC. These data provide the first evidence that FAK expression is critical for the regulation of thyroid tumorigenic functions.

Implications: This study demonstrates that FAK expression, but not kinase activity alone, predominantly mediates thyroid tumor growth and metastasis, indicating that targeting the scaffolding function(s) of FAK may be an important therapeutic strategy for advanced thyroid cancer, as well as other FAK-dependent tumors. Mol Cancer Res; 14(9); 869–82. ©2016 AACR.
Data from MELK and EZH2 Cooperate to Regulate Medulloblastoma Cancer Stem-like Cell Proliferation and Differentiation
Authors: Liu Hailong , Sun Qianwen , Sun Youliang , Zhang Junping , Yuan Hongyu , Pang Shuhuan , Qi Xueling , Wang Haoran , Zhang Mingshan , Zhang Hongwei , Yu Chunjiang , Gu Chunyu
Published: March 2024

Abstract
Medulloblastoma is the most common malignant brain tumor in children. Although accumulated research has suggested that cancer stem-like cells play a key role in medulloblastoma tumorigenesis, the specific molecular mechanism regarding proliferation remains elusive. Here, we reported more abundant expression of maternal embryonic leucine-zipper kinase (MELK) and enhancer of zeste homolog 2 (EZH2) in medulloblastoma stem-like cells than in neural stem cells and the interaction between the two proteins could mediate the self-renewal of sonic hedgehog subtype medulloblastoma. In human medulloblastoma, extensive nodularity and large-cell/anaplastic subgroups differed according to the staining levels of MELK and EZH2 from the other two subgroups. The proportion of MELK- or EZH2-positive staining status could be considered as a potential indicator for survival. Mechanistically, MELK bound to and phosphorylated EZH2, and its methylation was induced by EZH2 in medulloblastoma, which could regulate the proliferation of cancer stem-like cells. In xenografts, loss of MELK or EZH2 attenuated medulloblastoma stem-like cell-derived tumor growth and promoted differentiation. These findings indicate that MELK-induced phosphorylation and EZH2-mediated methylation in MELK/EZH2 pathway are essential for medulloblastoma stem-like cell-derived tumor proliferation, thereby identifying a potential therapeutic strategy for these patients.

Implications: This study demonstrates that the interaction occurring between MELK and EZH2 promotes self-proliferation and stemness, thus representing an attractive therapeutic target and potential candidate for diagnosis of medulloblastoma. Mol Cancer Res; 15(9); 1275–86. ©2017 AACR.
Data from PARP1 Trapping by PARP Inhibitors Drives Cytotoxicity in Both Cancer Cells and Healthy Bone Marrow
Authors: Hopkins Todd A. , Ainsworth William B. , Ellis Paul A. , Donawho Cherrie K. , DiGiammarino Enrico L. , Panchal Sanjay C. , Abraham Vivek C. , Algire Mikkel A. , Shi Yan , Olson Amanda M. , Johnson Eric F. , Wilsbacher Julie L. , Maag David
Published: March 2024

Abstract
PARP inhibitors have recently been approved as monotherapies for the treatment of recurrent ovarian cancer and metastatic BRCA-associated breast cancer, and ongoing studies are exploring additional indications and combinations with other agents. PARP inhibitors trap PARP onto damaged chromatin when combined with temozolomide and methyl methanesulfonate, but the clinical relevance of these findings remains unknown. PARP trapping has thus far been undetectable in cancer cells treated with PARP inhibitors alone. Here, we evaluate the contribution of PARP trapping to the tolerability and efficacy of PARP inhibitors in the monotherapy setting. We developed a novel implementation of the proximity ligation assay to detect chromatin-trapped PARP1 at single-cell resolution with higher sensitivity and throughput than previously reported methods. We further demonstrate that the PARP inhibitor–induced trapping appears to drive single-agent cytotoxicity in healthy human bone marrow, indicating that the toxicity of trapped PARP complexes is not restricted to cancer cells with homologous recombination deficiency. Finally, we show that PARP inhibitors with dramatically different trapping potencies exhibit comparable tumor growth inhibition at MTDs in a xenograft model of BRCA1-mutant triple-negative breast cancer. These results are consistent with emerging clinical data and suggest that the inverse relationship between trapping potency and tolerability may limit the potential therapeutic advantage of potent trapping activity.
Implications:
PARP trapping contributes to single-agent cytotoxicity of PARP inhibitors in both cancer cells and healthy bone marrow, and the therapeutic advantage of potent trapping activity appears to be limited.
Data from ERG Oncoprotein Inhibits ANXA2 Expression and Function in Prostate Cancer
Authors: Griner Nicholas B. , Young Denise , Chaudhary Pankaj , Mohamed Ahmed A. , Huang Wei , Chen Yongmei , Sreenath Taduru , Dobi Albert , Petrovics Gyorgy , Vishwanatha Jamboor K. , Sesterhenn Isabell A. , Srivastava Shiv , Tan Shyh-Han
Published: March 2024

Abstract
Overexpression of ERG in the prostate epithelium, due to chromosomal translocations, contributes to prostate tumorigenesis. Here, genomic analysis of ERG siRNA-treated prostate cells harboring the endogenous TMPRSS2–ERG fusion revealed an inverse relationship between ERG and Annexin A2 (ANXA2) expression at both the RNA and protein level. ANXA2, a Ca2+-dependent and phospholipid-binding protein, is involved in various cellular functions, including maintenance of epithelial cell polarity. Mechanistic studies defined the prostate-specific transcription start site of ANXA2 and showed that the recruitment of ERG to the ANXA2 promoter is required for transcriptional repression by ERG. Knockdown of ERG enhanced the apical localization of ANXA2, the bundling of actin filaments at cell–cell junctions and formation of a polarized epithelial phenotype. ERG overexpression disrupted ANXA2-mediated cell polarity and promoted epithelial–mesenchymal transition (EMT) by inhibiting CDC42 and RHOA, and by activating cofilin. Immunohistochemistry demonstrated a reciprocal relationship of ANXA2 and ERG expression in a large fraction of primary prostate cancer clinical specimens. ANXA2 was absent or markedly reduced in ERG(+) tumors, which were mostly well differentiated. ERG(−) tumors, meanwhile, expressed moderate to high levels of ANXA2, and were either poorly differentiated or displayed subsets of poorly differentiated cells. Taken together, the transcriptional repression of ANXA2 by ERG in prostate epithelial cells plays a critical role in abrogating differentiation, promoting EMT, and in the reciprocal correlation of ERG and ANXA2 expression observed in human prostate cancer.

Implications: ANXA2 is a new component of the ERG network with potential to enhance biologic stratification and therapeutic targeting of ERG-stratified prostate cancers. Mol Cancer Res; 13(2); 368–79. ©2014 AACR.
Data from Targeting RRM2 and Mutant BRAF Is a Novel Combinatorial Strategy for Melanoma
Authors: Fatkhutdinov Nail , Sproesser Katrin , Krepler Clemens , Liu Qin , Brafford Patricia A. , Herlyn Meenhard , Aird Katherine M. , Zhang Rugang
Published: March 2024

Abstract
The majority of patients with melanoma harbor mutations in the BRAF oncogene, thus making it a clinically relevant target. However, response to mutant BRAF inhibitors (BRAFi) is relatively short-lived with progression-free survival of only 6 to 7 months. Previously, we reported high expression of ribonucleotide reductase M2 (RRM2), which is rate-limiting for de novo dNTP synthesis, as a poor prognostic factor in patients with mutant BRAF melanoma. In this study, the notion that targeting de novo dNTP synthesis through knockdown of RRM2 could prolong the response of melanoma cells to BRAFi was investigated. Knockdown of RRM2 in combination with the mutant BRAFi PLX4720 (an analog of the FDA-approved drug vemurafenib) inhibited melanoma cell proliferation to a greater extent than either treatment alone. This occurred in vitro in multiple mutant BRAF cell lines and in a novel patient-derived xenograft (PDX) model system. Mechanistically, the combination increased DNA damage accumulation, which correlated with a global decrease in DNA damage repair (DDR) gene expression and increased apoptotic markers. After discontinuing PLX4720 treatment, cells showed marked recurrence. However, knockdown of RRM2 attenuated this rebound growth both in vitro and in vivo, which correlated with maintenance of the senescence-associated cell-cycle arrest.

Implications: Inhibition of RRM2 converts the transient response of melanoma cells to BRAFi to a stable response and may be a novel combinatorial strategy to prolong therapeutic response of patients with melanoma. Mol Cancer Res; 14(9); 767–75. ©2016 AACR.
Data from p53 and ΔNp63α Coregulate the Transcriptional and Cellular Response to TGFβ and BMP Signals
Authors: Balboni Amanda L. , Cherukuri Pratima , Ung Matthew , DeCastro Andrew J. , Cheng Chao , DiRenzo James
Published: March 2024

Abstract
The TGFβ superfamily regulates a broad range of cellular processes, including proliferation, cell-fate specification, differentiation, and migration. Molecular mechanisms underlying this high degree of pleiotropy and cell-type specificity are not well understood. The TGFβ family is composed of two branches: (i) TGFβs, activins, and nodals, which signal through SMAD2/3, and (ii) bone morphogenetic proteins (BMP), which signal through SMAD1/5/8. SMADs have weak DNA-binding affinity and rely on coactivators and corepressors to specify their transcriptional outputs. This report reveals that p53 and ΔNp63α act as transcriptional partners for SMAD proteins and thereby influence cellular responses to TGFβ and BMPs. Suppression of p53 or overexpression of ΔNp63α synergistically enhance BMP-induced transcription. Mechanistically, p53 and ΔNp63α physically interact with SMAD1/5/8 proteins and co-occupy the promoter region of inhibitor of differentiation (ID2), a prosurvival BMP target gene. Demonstrating further convergence of these pathways, TGFβ-induced canonical BMP regulated transcription in a ΔNp63α- and p53-dependent manner. Furthermore, bioinformatic analyses revealed that SMAD2/3 and ΔNp63α coregulate a significant number of transcripts involved in the regulation of epithelial-to-mesenchymal transition. Thus, p53 and ΔNp63α are transcriptional partners for a subset of TGFβ- and BMP-regulated SMAD target genes in the mammary epithelium. Collectively, these results establish an integrated gene network of SMADs, p53, and ΔNp63α that contribute to EMT and metastasis.

Implications: This study identifies aberrant BMP activation as a result of p53 mutation or ΔNp63α expression. Mol Cancer Res; 13(4); 732–42. ©2015 AACR.
Data from Let-7e Suppresses DNA Damage Repair and Sensitizes Ovarian Cancer to Cisplatin through Targeting PARP1
Authors: Xiao Man , Guo Jianfeng , Xie Lisha , Yang Chun , Gong Lanqing , Wang Zehua , Cai Jing
Published: March 2024

Abstract
Increased DNA damage repair is one of the mechanisms implicated in cisplatin resistance. Our previous study indicated that the deregulation of let-7e promoted cisplatin resistance and that let-7e could suppress DNA double-strand break repair in ovarian cancer. In this study, we further characterized the role of let-7e in DNA damage repair and cisplatin resistance in ovarian cancer, and investigated the underlying mechanisms. The alkaline and neutral comet assay indicated that let-7e impeded both DNA single- and double-strand break repairs through downregulating its target gene PARP1. In vitro and in vivo experiments provided evidence that the let-7e–PARP1–DNA repair axis was involved in the modulation of cisplatin sensitivity in ovarian cancer. Contrary to let-7e, PARP1 was overexpressed in cisplatin-resistant ovarian cancer tissues, and patients with high PARP1 expression exhibited poor progression-free survival (PFS) and overall survival (OS). Multivariate logistic and Cox regression analyses showed that let-7e and FIGO stage were independent prognostic factors for PFS and OS, whereas let-7e and PARP1 were able to independently predict chemotherapy response. Taken together, our results indicated that low expression of let-7e promoted DNA single- and double-strand break repairs and subsequently contributed to cisplatin resistance by relieving the suppression on PARP1 in ovarian cancer.
Implications:
Targeting the let-7e–PARP1–DNA repair axis might be an effective strategy for the treatment of chemoresistant ovarian cancer.
Data from Systematic siRNA Screen Unmasks NSCLC Growth Dependence by Palmitoyltransferase DHHC5
Authors: Tian Hui , Lu Jui-Yun , Shao Chunli , Huffman Kenneth E. , Carstens Ryan M. , Larsen Jill E. , Girard Luc , Liu Hui , Rodriguez-Canales Jaime , Frenkel Eugene P. , Wistuba Ignacio I. , Minna John D. , Hofmann Sandra L.
Published: March 2024

Abstract
Protein S-palmitoylation is a widespread and dynamic posttranslational modification that regulates protein–membrane interactions, protein–protein interactions, and protein stability. A large family of palmitoyl acyl transferases, termed the DHHC family due to the presence of a common catalytic motif, catalyzes S-palmitoylation; the role of these enzymes in cancer is largely unexplored. In this study, an RNAi-based screen targeting all 23 members of the DHHC family was conducted to examine the effects on the growth in non–small cell lung cancer (NSCLC). Interestingly, siRNAs directed against DHHC5 broadly inhibited the growth of multiple NSCLC lines but not normal human bronchial epithelial cell (HBEC) lines. Silencing of DHHC5 by lentivirus-mediated expression of DHHC5 shRNAs dramatically reduced in vitro cell proliferation, colony formation, and cell invasion in a subset of cell lines that were examined in further detail. The phenotypes were restored by transfection of a wild-type DHHC5 plasmid but not by a plasmid expressing a catalytically inactive DHHC5. Tumor xenograft formation was severely inhibited by DHHC5 knockdown and rescued by DHHC5 expression, using both a conventional and tetracycline-inducible shRNA. These data indicate that DHHC5 has oncogenic capacity and contributes to tumor formation in NSCLC, thus representing a potential novel therapeutic target.

Implications: Inhibitors of DHHC5 enzyme activity may inhibit non–small cell lung cancer growth. Mol Cancer Res; 13(4); 784–94. ©2015 AACR.
Data from Development of a Novel c-MET–Based CTC Detection Platform
Authors: Zhang Tian , Boominathan Rengasamy , Foulk Brad , Rao Chandra , Kemeny Gabor , Strickler John H. , Abbruzzese James L. , Harrison Michael R. , Hsu David S. , Healy Patrick , Li Jing , Pi Cinthia , Prendergast Katherine M. , Hobbs Carey , Gemberling Sarah , George Daniel J. , Hurwitz Herbert I. , Connelly Mark , Garcia-Blanco Mariano A. , Armstrong Andrew J.
Published: March 2024

Abstract
Amplification of the MET oncogene is associated with poor prognosis, metastatic dissemination, and drug resistance in many malignancies. We developed a method to capture and characterize circulating tumor cells (CTC) expressing c-MET using a ferromagnetic antibody. Immunofluorescence was used to characterize cells for c-MET, DAPI, and pan-CK, excluding CD45+ leukocytes. The assay was validated using appropriate cell line controls spiked into peripheral blood collected from healthy volunteers (HV). In addition, peripheral blood was analyzed from patients with metastatic gastric, pancreatic, colorectal, bladder, renal, or prostate cancers. CTCs captured by c-MET were enumerated, and DNA FISH for MET amplification was performed. The approach was highly sensitive (80%) for MET-amplified cells, sensitive (40%–80%) for c-MET–overexpressed cells, and specific (100%) for both c-MET–negative cells and in 20 HVs. Of 52 patients with metastatic carcinomas tested, c-MET CTCs were captured in replicate samples from 3 patients [gastric, colorectal, and renal cell carcinoma (RCC)] with 6% prevalence. CTC FISH demonstrated that MET amplification in both gastric and colorectal cancer patients and trisomy 7 with gain of MET gene copies in the RCC patient. The c-MET CTC assay is a rapid, noninvasive, sensitive, and specific method for detecting MET-amplified tumor cells. CTCs with MET amplification can be detected in patients with gastric, colorectal, and renal cancers.

Implications: This study developed a novel c-MET CTC assay for detecting c-MET CTCs in patients with MET amplification and warrants further investigation to determine its clinical applicability. Mol Cancer Res; 14(6); 539–47. ©2016 AACR.
Data from Cells Comprising the Prostate Cancer Microenvironment Lack Recurrent Clonal Somatic Genomic Aberrations
Authors: Bianchi-Frias Daniella , Basom Ryan , Delrow Jeffrey J. , Coleman Ilsa M. , Dakhova Olga , Qu Xiaoyu , Fang Min , Franco Omar E. , Ericson Nolan G. , Bielas Jason H. , Hayward Simon W. , True Lawrence , Morrissey Colm , Brown Lisha , Bhowmick Neil A. , Rowley David , Ittmann Michael , Nelson Peter S.
Published: March 2024

Abstract
Prostate cancer–associated stroma (CAS) plays an active role in malignant transformation, tumor progression, and metastasis. Molecular analyses of CAS have demonstrated significant changes in gene expression; however, conflicting evidence exists on whether genomic alterations in benign cells comprising the tumor microenvironment (TME) underlie gene expression changes and oncogenic phenotypes. This study evaluates the nuclear and mitochondrial DNA integrity of prostate carcinoma cells, CAS, matched benign epithelium and benign epithelium–associated stroma by whole-genome copy-number analyses, targeted sequencing of TP53, and FISH. Array comparative genomic hybridization (aCGH) of CAS revealed a copy-neutral diploid genome with only rare and small somatic copy-number aberrations (SCNA). In contrast, several expected recurrent SCNAs were evident in the adjacent prostate carcinoma cells, including gains at 3q, 7p, and 8q, and losses at 8p and 10q. No somatic TP53 mutations were observed in CAS. Mitochondrial DNA (mtDNA) extracted from carcinoma cells and stroma identified 23 somatic mtDNA mutations in neoplastic epithelial cells, but only one mutation in stroma. Finally, genomic analyses identified no SCNAs, LOH, or copy-neutral LOH in cultured cancer-associated fibroblasts, which are known to promote prostate cancer progression in vivo.

Implications: The gene expression changes observed in prostate cancer–adjacent stroma and the attendant contribution of the stroma to the development and progression of prostate cancer are not due to frequent or recurrent genomic alterations in the TME. Mol Cancer Res; 14(4); 374–84. ©2016 AACR.
Data from Helicobacter pylori Induces a Novel NF-kB/LIN28A/let-7a/hTERT Axis to Promote Gastric Carcinogenesis
Authors: Shen Li , Zeng Jiping , Ma Lin , Li Shuyan , Chen Chunyan , Jia Jihui , Liang Xiuming
Published: March 2024

Abstract
Reactivated telomerase is a crucial event in the development and progression of a variety of tumors. However, how telomerase is activated in gastric carcinogenesis has not been fully uncovered yet. Here, we identified a key role of the NF-κB/LIN28A/let-7a axis to promote human telomerase reverse transcriptase (hTERT) expression for gastric cancer initiation. Mechanistically, LIN28A expression was upregulated by H. pylori–induced NF-κB activation. And LIN28A, in turn, suppressed let-7a expression, forming the NF-κB/LIN28A/let-7a axis to regulate gene expression upon H. pylori infection. Of note, we first discovered hTERT as a direct target of let-7a, which inhibited hTERT expression by binding to its 3′UTR of mRNA. Therefore, H. pylori–triggered let-7a downregulation enhanced hTERT protein translation, resulting in telomerase reactivation. Furthermore, hTERT enhanced LIN28A expression, forming the positive feedback regulation between hTERT and NF-κB/LIN28A/let-7a axis to maintain the sustained overexpression of hTERT in gastric cancer.
Implications:
The NF-κB/LIN28A/Let-7a axis was crucial for the overexpression of hTERT upon H. pylori infection during gastric cancer development and may serve as a potential target to suppress hTERT expression for gastric cancer prevention and treatment.
Data from Hypoxic Cancer-Secreted Exosomal miR-182-5p Promotes Glioblastoma Angiogenesis by Targeting Kruppel-like Factor 2 and 4
Authors: Li Junjun , Yuan Hongliang , Xu Hao , Zhao Hongyang , Xiong Nanxiang
Published: March 2024

Abstract
Glioblastoma (GBM) is the most lethal primary brain tumor and has a complex molecular profile. Hypoxia plays a critical role during tumor progression and in the tumor microenvironment (TME). Exosomes released by tumor cells contain informative nucleic acids, proteins, and lipids involved in the interaction between cancer and stromal cells, thus leading to TME remodeling. Accumulating evidence indicates that exosomes play a pivotal role in cell-to-cell communication. However, the mechanism by which hypoxia affects tumor angiogenesis via exosomes derived from tumor cells remains largely unknown. In our study, we found that, compared with the parental cells under normoxic conditions, the GBM cells produced more exosomes, and miR-182-5p was significantly upregulated in the exosomes from GBM cells under hypoxic conditions. Exosomal miR-182-5p directly suppressed its targets Kruppel-like factor 2 and 4, leading to the accumulation of VEGFR, thus promoting tumor angiogenesis. Furthermore, exosome-mediated miR-182-5p also inhibited tight junction-related proteins (such as ZO-1, occludin, and claudin-5), thus enhancing vascular permeability and tumor transendothelial migration. Knockdown of miR-182-5p reduced angiogenesis and tumor proliferation. Interestingly, we found elevated levels circulating miR-182-5p in patient blood serum and cerebrospinal fluid samples, and its expression level was inversely related to the prognosis.
Implications:
Overall, our data clarify the diagnostic and prognostic value of tumor-derived exosome-mediated miR-182-5p and reveal the distinctive cross-talk between tumor cells and human umbilical vein endothelial cells mediated by tumor-derived exosomes that modulate tumor vasculature.
Data from 14-3-3σ Contributes to Radioresistance By Regulating DNA Repair and Cell Cycle via PARP1 and CHK2
Authors: Chen Yifan , Li Zhaomin , Dong Zizheng , Beebe Jenny , Yang Ke , Fu Liwu , Zhang Jian-Ting
Published: March 2024

Abstract
14-3-3σ has been implicated in the development of chemo and radiation resistance and in poor prognosis of multiple human cancers. While it has been postulated that 14-3-3σ contributes to these resistances via inhibiting apoptosis and arresting cells in G2–M phase of the cell cycle, the molecular basis of this regulation is currently unknown. In this study, we tested the hypothesis that 14-3-3σ causes resistance to DNA-damaging treatments by enhancing DNA repair in cells arrested in G2–M phase following DNA-damaging treatments. We showed that 14-3-3σ contributed to ionizing radiation (IR) resistance by arresting cancer cells in G2–M phase following IR and by increasing non-homologous end joining (NHEJ) repair of the IR-induced DNA double strand breaks (DSB). The increased NHEJ repair activity was due to 14-3-3σ–mediated upregulation of PARP1 expression that promoted the recruitment of DNA-PKcs to the DNA damage sites for repair of DSBs. On the other hand, the increased G2–M arrest following IR was due to 14-3-3σ–induced Chk2 expression.

Implications: These findings reveal an important molecular basis of 14-3-3σ function in cancer cell resistance to chemo/radiation therapy and in poor prognosis of human cancers. Mol Cancer Res; 15(4); 418–28. ©2017 AACR.
Data from miR-122-5p Expression and Secretion in Melanoma Cells Is Amplified by the LPAR3 SH3–Binding Domain to Regulate Wnt1
Authors: Byrnes Charnel C. , Jia Wei , Alshamrani Ali A. , Kuppa Sudeepti S. , Murph Mandi M.
Published: March 2024

Abstract
The lysophosphatidic acid receptor-3 (LPAR3) is a G protein–coupled receptor that mediates viability among malignant cells and aggressiveness among certain tumors. The study's objective was to determine the interplay between LPAR3 and miRNAs to impact key cellular signaling pathways. Using SK-Mel-2 and SK-Mel-5 melanoma cells, wild-type and mutated receptors were stably expressed to explore molecular mechanisms. LPAR3 signaling induced miR-122-5p intracellularly and subsequently its inclusion into exosomes. This amplification resulted in less abundant Wnt1, maintenance of GSK3 inactivation and to a lesser extent, partial degradation of β-catenin. The surge in miR-122-5p and reduction in Wnt1 originated from signaling at the Src homology 3 (SH3) ligand–binding motif within the third intracellular loop of LPAR3, because mutant receptors did not increase miR-122-5p and had a weakened capacity to reduce Wnt1. In addition, a key mediator of melanoma survival signaling, the peroxisome proliferator-activated receptor gamma coactivator 1-α (PPARGC1A/PGC1), was involved in miR-122-5p transcription. In conclusion, this study highlights the powerful role miRNAs have in fine-tuning specific G protein–coupled receptor-mediated signaling events by altering the transcription of signaling transduction pathway components. This study also identifies that LPAR3 increases miR-122-5p expression, which occurs mechanistically through the SH3 domain and helps explain why miR-122-5p increases are detected in cancer patient serum.
Implications:
LPAR3 is partially responsible for the production and secretion of miR-122-5p, found in the serum of a wide variety of patients with cancer.
Data from β2-adrenoreceptor Signaling Increases Therapy Resistance in Prostate Cancer by Upregulating MCL1
Authors: Hassan Sazzad , Pullikuth Ashok , Nelson Kyle C. , Flores Anabel , Karpova Yelena , Baiz Daniele , Zhu Sinan , Sui Guangchao , Huang Yue , Choi Young A. , D'Agostino Ralph , Hemal Ashok , von Holzen Urs , Debinski Waldemar , Kulik George
Published: March 2024

Abstract
There is accumulating evidence that continuous activation of the sympathetic nervous system due to psychosocial stress increases resistance to therapy and accelerates tumor growth via β2-adrenoreceptor signaling (ADRB2). However, the effector mechanisms appear to be specific to tumor type. Here we show that activation of ADRB2 by epinephrine, increased in response to immobilization stress, delays the loss of MCL1 apoptosis regulator (MCL1) protein expression induced by cytotoxic drugs in prostate cancer cells; and thus, increases resistance of prostate cancer xenografts to cytotoxic therapies. The effect of epinephrine on MCL1 protein depended on protein kinase A (PKA) activity, but was independent from androgen receptor expression. Furthermore, elevated blood epinephrine levels correlated positively with an increased MCL1 protein expression in human prostate biopsies. In summary, we demonstrate that stress triggers an androgen-independent antiapoptotic signaling via the ADRB2/PKA/MCL1 pathway in prostate cancer cells.
Implications:
Presented results justify clinical studies of ADRB2 blockers as therapeutics and of MCL1 protein expression as potential biomarker predicting efficacy of apoptosis-targeting drugs in prostate cancer.
Data from Synergistic Activity with NOTCH Inhibition and Androgen Ablation in ERG-Positive Prostate Cancer Cells
Authors: Mohamed Ahmed A. , Tan Shyh-Han , Xavier Charles P. , Katta Shilpa , Huang Wei , Ravindranath Lakshmi , Jamal Muhammad , Li Hua , Srivastava Meera , Srivatsan Eri S. , Sreenath Taduru L. , McLeod David G. , Srinivasan Alagarsamy , Petrovics Gyorgy , Dobi Albert , Srivastava Shiv
Published: March 2024

Abstract
The oncogenic activation of the ETS-related gene (ERG) due to gene fusions is present in over half of prostate cancers in Western countries. Because of its high incidence and oncogenic role, ERG and components of ERG network have emerged as potential drug targets for prostate cancer. Utilizing gene expression datasets, from matched normal and prostate tumor epithelial cells, an association of NOTCH transcription factors with ERG expression status was identified, confirming that NOTCH factors are direct transcriptional targets of ERG. Inhibition of ERG in TMPRSS2-ERG–positive VCaP cells led to decreased levels of NOTCH1 and 2 proteins and downstream transcriptional targets and partially recapitulated the phenotypes associated with ERG inhibition. Regulation of NOTCH1 and 2 genes by ERG were also noted with ectopic ERG expression in LNCaP (ERG-negative prostate cancer) and RWPE-1 (benign prostate–derived immortalized) cells. Furthermore, inhibition of NOTCH by the small-molecule γ-secretase inhibitor 1, GSI-1, conferred an increased sensitivity to androgen receptor (AR) inhibitors (bicalutamide and enzalutamide) or the androgen biosynthesis inhibitor (abiraterone) in VCaP cells. Combined treatment with bicalutamide and GSI-1 showed strongest inhibition of AR, ERG, NOTCH1, NOTCH2, and PSA protein levels along with decreased cell growth, cell survival, and enhanced apoptosis. Intriguingly, this effect was not observed in ERG-negative prostate cancer cells or immortalized benign/normal prostate epithelial cells. These data underscore the synergy of AR and NOTCH inhibitors in reducing the growth of ERG-positive prostate cancer cells.

Implications: Combinational targeting of NOTCH and AR signaling has therapeutic potential in advanced ERG-driven prostate cancers. Mol Cancer Res; 15(10); 1308–17. ©2017 AACR.
Data from Growth Factor–Independent 1 Is a Tumor Suppressor Gene in Colorectal Cancer
Authors: Chen Min-Shan , Lo Yuan-Hung , Chen Xi , Williams Christopher S. , Donnelly Jessica M. , Criss Zachary K. , Patel Shreena , Butkus Joann M. , Dubrulle Julien , Finegold Milton J. , Shroyer Noah F.
Published: March 2024

Abstract
Colorectal cancer is the third most common cancer and the third leading cause of cancer death in the United States. Growth factor–independent 1 (GFI1) is a zinc finger transcriptional repressor responsible for controlling secretory cell differentiation in the small intestine and colon. GFI1 plays a significant role in the development of human malignancies, including leukemia, lung cancer, and prostate cancer. However, the role of GFI1 in colorectal cancer progression is largely unknown. Our results demonstrate that RNA and protein expression of GFI1 are reduced in advanced-stage nonmucinous colorectal cancer. Subcutaneous tumor xenograft models demonstrated that the reexpression of GFI1 in 4 different human colorectal cancer cell lines inhibits tumor growth. To further investigate the role of Gfi1 in de novo colorectal tumorigenesis, we developed transgenic mice harboring a deletion of Gfi1 in the colon driven by CDX2-cre (Gfi1F/F; CDX2-cre) and crossed them with ApcMin/+ mice (ApcMin/+; Gfi1F/F; CDX2-cre). Loss of Gfi1 significantly increased the total number of colorectal adenomas compared with littermate controls with an APC mutation alone. Furthermore, we found that compound (ApcMin/+; Gfi1F/F; CDX2-cre) mice develop larger adenomas, invasive carcinoma, as well as hyperplastic lesions expressing the neuroendocrine marker chromogranin A, a feature that has not been previously described in APC-mutant tumors in mice. Collectively, these results demonstrate that GFI1 acts as a tumor suppressor gene in colorectal cancer, where deficiency of Gfi1 promotes malignancy in the colon.
Implications:
These findings reveal that GFI1 functions as a tumor suppressor gene in colorectal tumorigenesis.
Data from Combinations of Tyrosine Kinase Inhibitor and ERAD Inhibitor Promote Oxidative Stress–Induced Apoptosis through ATF4 and KLF9 in Medullary Thyroid Cancer
Authors: Bagheri-Yarmand Rozita , Sinha Krishna M. , Li Ling , Lu Yue , Cote Gilbert J. , Sherman Steven I. , Gagel Robert F.
Published: March 2024

Abstract
Medullary thyroid carcinoma (MTC) originates from the C cells of the thyroid gland, which secrete calcitonin. Lymph node and distant metastases are frequently present at diagnosis. Activating mutations of RET, a driver oncogene in MTC that encodes a tyrosine kinase receptor, prevents apoptosis through inhibition of ATF4, a key transcriptional regulator of endoplasmic reticulum (ER) stress. We hypothesized that the combination of a tyrosine kinase inhibitor (TKI) and an ATF4 inducer promotes cell death by triggering catastrophic oxidative stress and apoptotic cell death. Here, we report that the ER-associated protein degradation (ERAD) inhibitor eeyarestatin sensitized MTC cells to the TKIs, sunitinib and vandetanib, thereby leading to synergistic upregulation of ATF4 expression, accumulation of reactive oxygen species, and subsequent cell death. Genome-wide analysis of ATF4 interaction sites by chromatin immunoprecipitation (ChIP) sequencing revealed that among ATF4 target genes was KLF9 (Kruppel-like factor 9), which induces MTC apoptosis. ChIP assays revealed that ATF4 occupancy at the KLF9 promoter was increased in MTC cells treated with eeyarestatin or vandetanib alone and was further enhanced in cells treated with both drugs, leading to increased KLF9 transcription. Depletion of ATF4 by shRNA led to downregulation of KLF9 expression and prevented oxidative stress–induced cell death. Furthermore, we identified ATF4 target genes (LZTFL1, MKNK2, and SIAH1 with known tumor suppressor function) that were synergistically upregulated with the combination of TKI and ERAD inhibitor.
Implications:
These findings reveal a combination therapy that induces reactive oxygen species–dependent catastrophic cell death through induction of ATF4 and KLF9 transcriptional activity.
Data from Blockade of AP-1 Potentiates Endocrine Therapy and Overcomes Resistance
Authors: Malorni Luca , Giuliano Mario , Migliaccio Ilenia , Wang Tao , Creighton Chad J. , Lupien Mathieu , Fu Xiaoyong , Hilsenbeck Susan G. , Healy Nuala , De Angelis Carmine , Mazumdar Abhijit , Trivedi Meghana V. , Massarweh Suleiman , Gutierrez Carolina , De Placido Sabino , Jeselsohn Rinath , Brown Myles , Brown Powel H. , Osborne C. Kent , Schiff Rachel
Published: March 2024

Abstract
The transcription factor AP-1 is downstream of growth factor (GF) receptors (GFRs) and stress-related kinases, both of which are implicated in breast cancer endocrine resistance. Previously, we have suggested that acquired endocrine resistance is associated with increased activity of AP-1 in an in vivo model. In this report, we provide direct evidence for the role of AP-1 in endocrine resistance. First, significant overlap was found between genes modulated in tamoxifen resistance and a gene signature associated with GF-induced estrogen receptor (ER) cistrome. Interestingly, these overlapping genes were enriched for key signaling components of GFRs and stress-related kinases and had AP-1 motifs in their promoters/enhancers. Second, to determine a more definitive role of AP-1 in endocrine resistance, AP-1 was inhibited using an inducible dominant-negative (DN) cJun expressed in MCF7 breast cancer cells in vitro and in vivo. AP-1 blockade enhanced the antiproliferative effect of endocrine treatments in vitro, accelerated xenograft tumor response to tamoxifen and estrogen deprivation in vivo, promoted complete regression of tumors, and delayed the onset of tamoxifen resistance. Induction of DN-cJun after the development of tamoxifen resistance resulted in dramatic tumor shrinkage, accompanied by reduced proliferation and increased apoptosis. These data suggest that AP-1 is a key determinant of endocrine resistance by mediating a global shift in the ER transcriptional program.

Implications: AP-1 represents a viable therapeutic target to overcome endocrine resistance. Mol Cancer Res; 14(5); 470–81. ©2016 AACR.
Data from Loss of Fas Expression and Function Is Coupled with Colon Cancer Resistance to Immune Checkpoint Inhibitor Immunotherapy
Authors: Xiao Wei , Ibrahim Mohammed L. , Redd Priscilla S. , Klement John D. , Lu Chunwan , Yang Dafeng , Savage Natasha M. , Liu Kebin
Published: March 2024

Abstract
Despite the remarkable efficacy of immune checkpoint inhibitor (ICI) immunotherapy in various types of human cancers, colon cancer, except for the approximately 4% microsatellite-instable (MSI) colon cancer, does not respond to ICI immunotherapy. ICI acts through activating CTLs that use the Fas–FasL pathway as one of the two effector mechanisms to suppress tumor. Cancer stem cells are often associated with resistance to therapy including immunotherapy, but the functions of Fas in colon cancer apoptosis and colon cancer stem cells are currently conflicting and highly debated. We report here that decreased Fas expression is coupled with a subset of CD133+CD24lo colon cancer cells in vitro and in vivo. Consistent of the lower Fas expression level, this subset of CD133+CD24loFaslo colon cancer cells exhibits decreased sensitivity to FasL-induced apoptosis. Furthermore, FasL selectively enriches CD133+CD24loFaslo colon cancer cells. CD133+CD24loFaslo colon cancer cells exhibit increased lung colonization potential in experimental metastatic mouse models and decreased sensitivity to tumor-specific CTL adoptive transfer and ICI immunotherapies. Interestingly, FasL challenge selectively enriched this subset of colon cancer cells in microsatellite-stable (MSS) but not in the MSI human colon cancer cell lines. Consistent with the downregulation of Fas expression in CD133+CD24lo cells, lower Fas expression level is significantly correlated with decreased survival in patients with human colon cancer.
Implications:
Our data determine that CD133+CD24loFaslo colon cancer cells are capable to evade Fas-FasL cytotoxicity of tumor-reactive CTLs and targeting this subset of colon cancer cells is potentially an effective approach to suppress colon cancer immune evasion.
Data from Inhibition of Aurora-A Promotes CD8+ T-Cell Infiltration by Mediating IL10 Production in Cancer Cells
Authors: Han Jing , Jiang Zhen , Wang Chennan , Chen Xin , Li Rongqing , Sun Na , Liu Xiangye , Wang Hui , Hong Li , Zheng Kuiyang , Yang Jing , Ikezoe Takayuki
Published: March 2024

Abstract
Intratumoral tumor-specific activated CD8+ T cells with functions in antitumor immune surveillance predict metastasis and clinical outcome in human colorectal cancer. Intratumoral CD8+ T cells also affect treatment with immune checkpoint inhibitors. Interestingly, inhibition of Aurora kinase A (Aurora-A) by its selective inhibitor alisertib obviously induced infiltration of CD8+ T cells. However, the mechanisms by which inhibition of Aurora-A promotes infiltration of intratumoral CD8+ T cells remain unclear. Our recent results demonstrated that conditional deletion of the AURKA gene or blockade of Aurora-A by alisertib slowed tumor growth in association with an increase in the infiltration of intratumoral CD8+ T cells as well as the mRNA levels of their IL10 receptor α (IL10Rα). The antitumor effects of targeting Aurora-A were attenuated in the absence of CD8+ T cells. In addition, antibody-mediated blockade of IL10Rα dramatically decreased the percentage of intratumoral CD8+ T cells. In further experiments, we found that the levels of IL10 were elevated in the serum of azoxymethane/dextran sodium sulfate-treated AURKAflox/+;VillinCre+ mice. Unexpectedly, we found that in addition to Aurora-A's mitotic role, inhibition of Aurora-A elevated IL10 transcription, which in turn increased the IL10Rα mRNA levels in CD8+ T cells. Thus, inhibition of Aurora-A could be a useful treatment strategy for recruiting tumor-specific intratumoral CD8+ T cells.
Implications:
Understanding the mechanisms by which inhibition of Aurora-A promotes CD8+ T-cell infiltration and activation, as mediated by the IL10 pathway could provide a potential strategy for tumor immunotherapy.