bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from CHP2 Promotes Cell Proliferation in Breast Cancer via Suppression of FOXO3a
Authors: Zhao Xiaohui , Xie Tian , Dai Ting , Zhao Wenhui , Li Jing , Xu Rui , Jiang Chao , Li Peiqiong , Deng Junyao , Su Xiaobo , Ma Ningfang
Published: March 2024

Abstract
Calcineurin B homologous protein isoform 2 (CHP2), an essential cofactor for Na+/H+ exchanger isoform 1 (NHE1), is identified to be expressed in various malignant cell lines. However, the clinical significance and biological role of CHP2 in breast cancer remain to be established. Here, CHP2 was markedly overexpressed in breast cancer cells and clinical tumor specimens. Immunohistochemical analysis revealed that the expression of CHP2 was significantly correlated with patients' clinicopathologic characteristics like clinical stage, and breast cancer patients with high CHP2 expression had shorter overall survival compared with patients with low CHP2 expression. Moreover, it was demonstrated that overexpressing CHP2 significantly enhanced, whereas silencing endogenous CHP2 inhibited, the proliferation and tumorigenicity of breast cancer cells in vitro and in vivo. In addition, overexpression of CHP2 accelerated, whereas inhibition of CHP2 retarded, G1–S phase cell-cycle transition in breast cancer cells. Mechanistically, overexpression of CHP2 activated AKT signaling and suppressed the transactivation of the forkhead box O3 (FOXO3/FOXO3a) transcription factor.

Implications: This study discovers a previously unrecognized role of CHP2 in the progression of breast cancer and supports the significance of this gene as a novel prognostic biomarker and a potential therapeutic target for breast cancer. Mol Cancer Res; 16(10); 1512–22. ©2018 AACR.
Data from AR Expression in Breast Cancer CTCs Associates with Bone Metastases
Authors: Aceto Nicola , Bardia Aditya , Wittner Ben S. , Donaldson Maria C. , O'Keefe Ryan , Engstrom Amanda , Bersani Francesca , Zheng Yu , Comaills Valentine , Niederhoffer Kira , Zhu Huili , Mackenzie Olivia , Shioda Toshi , Sgroi Dennis , Kapur Ravi , Ting David T. , Moy Beverly , Ramaswamy Sridhar , Toner Mehmet , Haber Daniel A. , Maheswaran Shyamala
Published: March 2024

Abstract
Molecular drivers underlying bone metastases in human cancer are not well understood, in part due to constraints in bone tissue sampling. Here, RNA sequencing was performed of circulating tumor cells (CTC) isolated from blood samples of women with metastatic estrogen receptor (ER)+ breast cancer, comparing cases with progression in bone versus visceral organs. Among the activated cellular pathways in CTCs from bone-predominant breast cancer is androgen receptor (AR) signaling. AR gene expression is evident, as is its constitutively active splice variant AR-v7. AR expression within CTCs is correlated with the duration of treatment with aromatase inhibitors, suggesting that it contributes to acquired resistance to endocrine therapy. In an established breast cancer xenograft model, a bone-tropic derivative displays increased AR expression, whose genetic or pharmacologic suppression reduces metastases to bone but not to lungs. Together, these observations identify AR signaling in CTCs from women with bone-predominant ER+ breast cancer, and provide a rationale for testing androgen inhibitors in this subset of patients.

Implications: This study highlights a role for the AR in breast cancer bone metastasis, and suggests that therapeutic targeting of the AR may benefit patients with metastatic breast cancer. Mol Cancer Res; 16(4); 720–7. ©2018 AACR.
Data from HuR Suppresses Fas Expression and Correlates with Patient Outcome in Liver Cancer
Authors: Zhu Haifeng , Berkova Zuzana , Mathur Rohit , Sehgal Lalit , Khashab Tamer , Tao Rong-Hua , Ao Xue , Feng Lei , Sabichi Anita L. , Blechacz Boris , Rashid Asif , Samaniego Felipe
Published: March 2024

Abstract
Hepatocellular carcinomas (HCC) show resistance to chemotherapy and have blunt response to apoptotic stimuli. HCC cell lines express low levels of the Fas death receptor and are resistant to FasL stimulation, whereas immortalized hepatocytes are sensitive. The variable Fas transcript levels and consistently low Fas protein in HCC cells suggest posttranscriptional regulation of Fas expression. The 3′-untranslated region (UTR) of Fas mRNA was found to interact with the ribonucleoprotein Human Antigen R (HuR) to block mRNA translation. Silencing of HuR in HCC cells increased the levels of cell surface Fas and sensitized HCC cells to FasL. Two AU-rich domains within the 3′-UTR of Fas mRNA were identified as putative HuR-binding sites and were found to mediate the translational regulation in reporter assay. Hydrodynamic transfection of HuR plasmid into mice induced downregulation of Fas expression in livers and established functional resistance to the killing effects of Fas agonist. Human HCC tumor tissues showed significantly higher overall and cytoplasmic HuR staining compared with normal liver tissues, and the high HuR staining score correlated with worse survival of patients with early-stage HCC. Combined, the protumorigenic ribonucleoprotein HuR blocks the translation of Fas mRNA and effectively prevents Fas-mediated apoptosis in HCC, suggesting that targeting HuR would sensitize cells to apoptotic stimuli and reverse tumorigenic properties.

Implications: Demonstrating how death receptor signaling pathways are altered during progression of HCC will enable the development of better methods to restore this potent apoptosis mechanism. Mol Cancer Res; 13(5); 809–18. ©2015 AACR.
Data from RNF8 Promotes Epithelial–Mesenchymal Transition in Lung Cancer Cells via Stabilization of Slug
Authors: Kuang Jingyu , Min Lu , Liu Chuanyang , Chen Si , Gao Changsong , Ma Jiaxin , Wu Xiaomin , Li Wenying , Wu Lei , Zhu Lingyun
Published: March 2024

Abstract
RNF8 (ring finger protein 8), a RING finger E3 ligase best characterized for its role in DNA repair and sperm formation via ubiquitination, has been found to promote tumor metastasis in breast cancer recently. However, whether RNF8 also plays a role in other types of cancer, especially in lung cancer, remains unknown. We show here that RNF8 expression levels are markedly increased in human lung cancer tissues and negatively correlated with the survival time of patients. Overexpression of RNF8 promotes the EMT process and migration ability of lung cancer cells, while knockdown of RNF8 demonstrates the opposite effects. In addition, overexpression of RNF8 activates the PI3K/Akt signaling pathway, knockdown of RNF8 by siRNA inhibits this activation, and pharmacologic inhibition of PI3K/Akt in RNF8-overexpressing cells also reduces the expression of EMT markers and the ability of migration. Furthermore, RNF8 is found to directly interact with Slug and promoted the K63-Ub of Slug, and knockdown of Slug disrupts RNF8-dependent EMT in A549 cells, whereas overexpression of Slug rescues RNF8-dependent MET in H1299 cells, and depletion of RNF8 expression by shRNA inhibits metastasis of lung cancer cells in vivo. Taken together, these results indicate that RNF8 is a key regulator of EMT process in lung cancer and suggest that inhibition of RNF8 could be a useful strategy for lung cancer treatment.
Implications:
This study provides a new mechanistic insight into the novel role of RNF8 and identifies RNF8 as a potential new therapeutic target for the treatment of lung cancer.
Data from Targeting Mutant PPM1D Sensitizes Diffuse Intrinsic Pontine Glioma Cells to the PARP Inhibitor Olaparib
Authors: Wang Zhaohui , Xu Cheng , Diplas Bill H. , Moure Casey J. , Chen Chin-Pu Jason , Chen Lee H. , Du Changzheng , Zhu Huishan , Greer Paula K. , Zhang Liwei , He Yiping , Waitkus Matthew S. , Yan Hai
Published: March 2024

Abstract
Diffuse intrinsic pontine glioma (DIPG) is an invariably fatal brain tumor occurring predominantly in children. Up to 90% of pediatric DIPGs harbor a somatic heterozygous mutation resulting in the replacement of lysine 27 with methionine (K27M) in genes encoding histone H3.3 (H3F3A, 65%) or H3.1 (HIST1H3B, 25%). Several studies have also identified recurrent truncating mutations in the gene encoding protein phosphatase 1D, PPM1D, in 9%–23% of DIPGs. Here, we sought to investigate the therapeutic potential of targeting PPM1D, alone or in combination with inhibitors targeting specific components of DNA damage response pathways in patient-derived DIPG cell lines. We found that GSK2830371, an allosteric PPM1D inhibitor, suppressed the proliferation of PPM1D-mutant, but not PPM1D wild-type DIPG cells. We further observed that PPM1D inhibition sensitized PPM1D-mutant DIPG cells to PARP inhibitor (PARPi) treatment. Mechanistically, combined PPM1D and PARP inhibition show synergistic effects on suppressing a p53-dependent RAD51 expression and the formation of RAD51 nuclear foci, possibly leading to impaired homologous recombination (HR)-mediated DNA repair in PPM1D-mutant DIPG cells. Collectively, our findings reveal the potential role of the PPM1D–p53 signaling axis in the regulation of HR-mediated DNA repair and provide preclinical evidence demonstrating that combined inhibition of PPM1D and PARP1/2 may be a promising therapeutic combination for targeting PPM1D-mutant DIPG tumors.
Implications:
The findings support the use of PARPi in combination with PPM1D inhibition against PPM1D-mutant DIPGs.
Data from lincRNA-RoR and miR-145 Regulate Invasion in Triple-Negative Breast Cancer via Targeting ARF6
Authors: Eades Gabriel , Wolfson Benjamin , Zhang Yongshu , Li Qinglin , Yao Yuan , Zhou Qun
Published: March 2024

Abstract
Triple-negative (ER−, HER2−, PR−) breast cancer (TNBC) is an aggressive disease with a poor prognosis with no available molecularly targeted therapy. Silencing of microRNA-145 (miR-145) may be a defining marker of TNBC based on molecular profiling and deep sequencing. Therefore, the molecular mechanism behind miR-145 downregulation in TNBC was examined. Overexpression of the long intergenic noncoding RNA regulator of reprogramming, lincRNA-RoR, functions as a competitive endogenous RNA sponge in TNBC. Interestingly, lincRNA-RoR is dramatically upregulated in TNBC and in metastatic disease and knockdown restores miR-145 expression. Previous reports suggest that miR-145 has growth-suppressive activity in some breast cancers; however, these data in TNBC indicate that miR-145 does not affect proliferation or apoptosis but instead, miR-145 regulates tumor cell invasion. Investigation of miR-145-regulated pathways involved in tumor invasion revealed a novel target, the small GTPase ADP-ribosylation factor 6 (Arf6). Subsequent analysis demonstrated that ARF6, a known regulator of breast tumor cell invasion, is dramatically upregulated in TNBC and in breast tumor metastasis. Mechanistically, ARF6 regulates E-cadherin localization and affects cell–cell adhesion. These results reveal a lincRNA-RoR/miR-145/ARF6 pathway that regulates invasion in TNBCs.

Implications: The lincRNA-RoR/miR-145/ARF6 pathway is critical to TNBC metastasis and could serve as biomarkers or therapeutic targets for improving survival. Mol Cancer Res; 13(2); 330–8. ©2014 AACR.
Data from AGO2 Mediates MYC mRNA Stability in Hepatocellular Carcinoma
Authors: Zhang Kai , Pomyen Yotsawat , Barry Anna E. , Martin Sean P. , Khatib Subreen , Knight Lucy , Forgues Marshonna , Dominguez Dana A. , Parhar Ravinder , Shah Ashesh P. , Bodzin Adam S. , Wang Xin Wei , Dang Hien
Published: March 2024

Abstract
Deregulated RNA-binding proteins (RBP), such as Argonaute 2 (AGO2), mediate tumor-promoting transcriptomic changes during carcinogenesis, including hepatocellular carcinoma (HCC). While AGO2 is well characterized as a member of the RNA-induced silencing complex (RISC), which represses gene expression through miRNAs, its role as a bona fide RBP remains unclear. In this study, we investigated AGO2′s role as an RBP that regulates the MYC transcript to promote HCC. Using mRNA and miRNA arrays from patients with HCC, we demonstrate that HCCs with elevated AGO2 levels are more likely to have the mRNA transcriptome deregulated and are associated with poor survival. Moreover, AGO2 overexpression stabilizes the MYC transcript independent of miRNAs. These observations provide a novel mechanism of gene regulation by AGO2 and provide further insights into the potential functions of AGO2 as an RBP in addition to RISC.
Implications:
Authors demonstrate that the RBP Argonaute 2 stabilizes the MYC transcript to promote HCC.
Data from Circular RNA hsa_circ_0014130 Inhibits Apoptosis in Non–Small Cell Lung Cancer by Sponging miR-136-5p and Upregulating BCL2
Authors: Geng Ying , Bao Yongxia , Deng Lili , Su Dongju , Zheng Hongyan , Zhang Wei
Published: March 2024

Abstract
Previous studies indicated that circular RNAs (circRNA) played vital roles in the development of non–small cell lung cancer (NSCLC). Although hsa_circ_0014130 might be a potential NSCLC biomarker, its function in NSCLC remains unknown. Thus, this study aimed to investigate the role of hsa_circ_0014130 in the progression of NSCLC. The levels of hsa_circ_0014130 in NSCLC tissues and adjacent normal tissues were determined by qRT-PCR. In addition, the expressions of Bcl-2 and cleaved caspase-3 in A549 cells were detected with Western blot analysis. Meanwhile, the dual luciferase reporter system assay was used to determine the interaction of hsa_circ_0014130 and miR-136-5p or Bcl-2 and miR-136-5p in NSCLC, respectively. The level of hsa_circ_0014130 was significantly upregulated in NSCLC tissues. Downregulation of hsa_circ_0014130 markedly inhibited the proliferation and invasion of A549 cells via inducing apoptosis. In addition, downregulation of hsa_circ_0014130 inhibited the tumorigenesis of subcutaneous A549 xenograft in mice in vivo. Meanwhile, mechanistic analysis indicated that downregulation of hsa_circ_0014130 decreased the expression of miR‐136‐5p–targeted gene Bcl-2 via acting as a competitive “sponge” of miR‐136-5p. In this study, we found that hsa_circ_0014130 was upregulated in NSCLC tissues. In addition, hsa_circ_0014130 functions as a tumor promoter in NSCLC to promote tumor growth through upregulating Bcl-2 partially via “sponging” miR‐136-5p.
Implications:
In conclusion, hsa_circ_0014130 might function as a prognostic factor for patients with NSCLC and might be a therapeutic target for the treatment of NSCLC in future.
Data from Gas1 Inhibits Metastatic and Metabolic Phenotypes in Colorectal Carcinoma
Authors: Li Qingguo , Qin Yi , Wei Ping , Lian Peng , Li Yaqi , Xu Ye , Li Xinxiang , Li Dawei , Cai Sanjun
Published: March 2024

Abstract
Growth arrest–specific 1 (Gas1) plays a critical role in growth suppression. Previous study indicated that Gas1 was closely associated with survival in patients with colorectal cancer; however, the underlying molecular mechanism remains unclear. In this study, we sought to determine the role of Gas1 in tumorigenesis and metastasis, and elucidate the possible mechanism. First, Gas1 was determined as a negative regulator of oncogenesis and metastasis in colorectal cancer. Mechanistically, Gas1 negatively regulated the aerobic glycolysis, a process that contributed to tumor progression and metastasis by providing energy source and building blocks for macromolecule synthesis. To further consolidate the role of Gas1 in glycolysis, the impact of Gas1 in the transcription of key glycolytic enzymes for glucose utilization was examined. As expected, GLUT4, HK2, and LDHB exhibited a decreased expression pattern. Consistent with this observation, an in vivo subcutaneous xenograft mouse model also confirmed the hypothesis that Gas1 is a negative regulator of glycolysis as reflected by the decreased 18FDG uptake in PET/CT system. Moreover, Gas1 negatively regulated the AMPK/mTOR/p70S6K signaling axis, a well-established cascade that regulates malignant cancer cell behaviors including proliferation, metastasis, and aberrant cancer metabolism. In the end, it was determined that Gas1 is a transcriptional target of FOXM1, whose role in colorectal cancer has been widely studied. Taken together, these studies establish Gas1 as a negative regulator in colorectal cancer.

Implications: Gas1 suppresses cell proliferation, invasion, and aerobic glycolysis of colorectal cancer both in vitro and in vivo. Mechanistically, Gas1 inhibited EMT and the Warburg effect via AMPK/mTOR/p70S6K signaling, and Gas1 itself was directly regulated by the transcription factor FOXM1. Mol Cancer Res; 14(9); 830–40. ©2016 AACR.
Data from PTPN3 Inhibits the Growth and Metastasis of Clear Cell Renal Cell Carcinoma via Inhibition of PI3K/AKT Signaling
Authors: Peng Xing-Si , Yang Jun-Ping , Qiang Yuan-Yuan , Sun Rui , Cao Yun , Zheng Li-Sheng , Peng Li-Xia , Lang Yan-Hong , Mei Yan , Li Chang-Zhi , Meng Dong-Fang , Liu Zhi-Jie , Wang Ming-Dian , Zhou Fang-Jian , Huang Bi-Jun , Qian Chao-Nan
Published: March 2024

Abstract
The underlying molecular mechanism driving clear cell renal cell carcinoma (ccRCC) progression is still to be explored. The significant downregulation of protein tyrosine phosphatase nonreceptor type 3 (PTPN3) expression in the tumor tissues suggested its protective role in ccRCC progression. IHC analysis of PTPN3 protein in 172 ccRCC tissue revealed that PTPN3 was an independently favorable prognostic factor for progression-free survival (P = 0.0166) and overall survival (P = 0.0343) of patients. The ccRCC cell lines SN12C, 1932, ACHN, and Caki-1 were used to evaluate, both in vitro and in vivo, the biological roles of PTPN3. We observed that overexpression of PTPN3 significantly inhibited the proliferation, migration, and invasion of ccRCC cells. In contrast, the knocking down of PTPN3 elicited opposite effects. Overexpressing PTPN3 inhibited xenograft tumor growth and lung metastasis displayed by the in vivo mice models. PTPN3 inhibited tumor cell motility by suppressing the phosphorylation of AKT, and subsequently inactivating the PI3K/AKT signaling pathway of renal cell carcinoma cells. Furthermore, the inhibition of phospho-AKTThr308 and phospho-AKTSer473 reversed PTPN3-induced silencing in tumor cell migration. Our work revealed that the overexpression of PTPN3 could suppress kidney cancer progression by negatively regulating the AKT signaling pathway, and served as a favorable prognostic factor in patients with ccRCC. Our findings provided insight that PTPN3 could be a potential target for therapy aiming to inhibit the malignant behaviors of ccRCC.
Implications:
PTPN3 is an independent favorable prognostic factor for patients with ccRCC and could be a potential target for therapy aiming to inhibit the malignant behaviors of ccRCC.
Data from EZH2 Represses Target Genes through H3K27-Dependent and H3K27-Independent Mechanisms in Hepatocellular Carcinoma
Authors: Gao Shu-Bin , Zheng Qi-Fan , Xu Bin , Pan Chang-Bao , Li Kang-Li , Zhao Yue , Zheng Qi-Lin , Lin Xiao , Xue Li-Xiang , Jin Guang-Hui
Published: March 2024

Abstract
Alterations of polycomb group (PcG) genes directly modulate the trimethylation of histone H3 lysine 27 (H3K27me3) and may thus affect the epigenome of hepatocellular carcinoma (HCC), which is crucial for controlling the HCC cell phenotype. However, the extent of downstream regulation by PcGs in HCC is not well defined. Using cDNA microarray analysis, we found that the target gene network of PcGs contains well-established genes, such as cyclin-dependent kinase inhibitors (CDKN2A), and genes that were previously undescribed for their regulation by PcG, including E2F1, NOTCH2, and TP53. Using chromatin immunoprecipitation assays, we demonstrated that EZH2 occupancy coincides with H3K27me3 at E2F1 and NOTCH2 promoters. Interestingly, PcG repress the expression of the typical tumor suppressor TP53 in human HCC cells, and an increased level of PcG was correlated with the downregulation of TP53 in certain HCC specimens. Unexpectedly, we did not find obvious H3K27me3 modification or an EZH2 binding signal at the TP53 promoters, suggesting that PcG regulates TP53 expression in an H3K27me3-independent manner. Finally, the reduced expression of PcGs effectively blocked the aggressive signature of liver cancer cells in vitro and in vivo.

Implications: Taken together, our results establish the functional and mechanistic significance of certain gene regulatory networks that are regulated by PcGs in HCC.

Visual Overview: http://mcr.aacrjournals.org/content/12/10/1388/F1.large.jpg.

Mol Cancer Res; 12(10); 1388–97. ©2014 AACR.
Data from OLR1 Promotes Pancreatic Cancer Metastasis via Increased c-Myc Expression and Transcription of HMGA2
Authors: Yang Gang , Xiong Guangbing , Feng Mengyu , Zhao Fangyu , Qiu Jiangdong , Liu Yueze , Cao Zhe , Wang Huanyu , Yang Jinshou , You Lei , Zheng Lianfang , Zhang Taiping , Zhao Yupei
Published: March 2024

Abstract
Pancreatic cancer is one of the most lethal human malignancies, partly because of its propensity for metastasis. However, the mechanisms of metastasis in pancreatic cancer remain unclear. Oxidized low-density lipoprotein receptor 1 (OLR1), a lectin-like scavenger receptor that recognizes several ligands, such as oxidized low-density lipoprotein, was previously reported in cardiovascular and metabolic diseases. The role and mechanism of OLR1 in pancreatic cancer is unclear. In this study, we found that OLR1 expression was significantly higher in pancreatic cancer tissues than that in adjacent normal tissues and closely associated with reduced overall survival. OLR1 promoted proliferation and metastasis of pancreatic cancer cells in vitro and in vivo. Mechanistically, OLR1 increased HMGA2 transcription by upregulating c-Myc expression to promote the metastasis of pancreatic cancer cells. In addition, patients with pancreatic cancer with high expression of OLR1–c-Myc–HMGA2 axis showed worse prognosis compared with patients with low expression of OLR1–c-Myc–HMGA2 axis.
Implications:
Our findings suggested that the OLR1–c-Myc–HMGA2 axis promotes metastasis of pancreatic cancer cells and may serve as potential therapeutic targets and prognosis markers for patients with pancreatic cancer.
Data from miR-29a Is Repressed by MYC in Pancreatic Cancer and Its Restoration Drives Tumor-Suppressive Effects via Downregulation of LOXL2
Authors: Dey Shatovisha , Kwon Jason J. , Liu Sheng , Hodge Gabriel A. , Taleb Solaema , Zimmers Teresa A. , Wan Jun , Kota Janaiah
Published: March 2024

Abstract
Pancreatic ductal adenocarcinoma (PDAC) is an intractable cancer with a dismal prognosis. miR-29a is commonly downregulated in PDAC; however, mechanisms for its loss and role still remain unclear. Here, we show that in PDAC, repression of miR-29a is directly mediated by MYC via promoter activity. RNA sequencing analysis, integrated with miRNA target prediction, identified global miR-29a downstream targets in PDAC. Target enrichment coupled with gene ontology and survival correlation analyses identified the top five miR-29a–downregulated target genes (LOXL2, MYBL2, CLDN1, HGK, and NRAS) that are known to promote tumorigenic mechanisms. Functional validation confirmed that upregulation of miR-29a is sufficient to ablate translational expression of these five genes in PDAC. We show that the most promising target among the identified genes, LOXL2, is repressed by miR-29a via 3′-untranslated region binding. Pancreatic tissues from a PDAC murine model and patient biopsies showed overall high LOXL2 expression with inverse correlations with miR-29a levels. Collectively, our data delineate an antitumorigenic, regulatory role of miR-29a and a novel MYC–miR-29a–LOXL2 regulatory axis in PDAC pathogenesis, indicating the potential of the molecule in therapeutic opportunities.
Implications:
This study unravels a novel functional role of miR-29a in PDAC pathogenesis and identifies an MYC–miR-29a–LOXL2 axis in regulation of the disease progression, implicating miR-29a as a potential therapeutic target for PDAC.
Visual Overview:
http://mcr.aacrjournals.org/content/molcanres/18/2/311/F1.large.jpg.
Data from Novel Small-Molecule CX3CR1 Antagonist Impairs Metastatic Seeding and Colonization of Breast Cancer Cells
Authors: Shen Fei , Zhang Yun , Jernigan Danielle L. , Feng Xin , Yan Jie , Garcia Fernando U. , Meucci Olimpia , Salvino Joseph M. , Fatatis Alessandro
Published: March 2024

Abstract
Recent evidence indicates that cancer cells, even in the absence of a primary tumor, recirculate from established secondary lesions to further seed and colonize skeleton and soft tissues, thus expanding metastatic dissemination and precipitating the clinical progression to terminal disease. Recently, we reported that breast cancer cells utilize the chemokine receptor CX3CR1 to exit the blood circulation and lodge to the skeleton of experimental animals. Now, we show that CX3CR1 is overexpressed in human breast tumors and skeletal metastases. To assess the clinical potential of targeting CX3CR1 in breast cancer, a functional role of CX3CR1 in metastatic seeding and progression was first validated using a neutralizing antibody for this receptor and transcriptional suppression by CRISPR interference (CRISPRi). Successively, we synthesized and characterized JMS-17-2, a potent and selective small-molecule antagonist of CX3CR1, which was used in preclinical animal models of seeding and established metastasis. Importantly, counteracting CX3CR1 activation impairs the lodging of circulating tumor cells to the skeleton and soft-tissue organs and also negatively affects further growth of established metastases. Furthermore, nine genes were identified that were similarly altered by JMS-17-2 and CRISPRi and could sustain CX3CR1 prometastatic activity. In conclusion, these data support the drug development of CX3CR1 antagonists, and promoting their clinical use will provide novel and effective tools to prevent or contain the progression of metastatic disease in breast cancer patients.

Implications: This work conclusively validates the instrumental role of CX3CR1 in the seeding of circulating cancer cells and is expected to pave the way for pairing novel inhibitors of this receptor with current standards of care for the treatment of breast cancer patients. Mol Cancer Res; 14(6); 518–27. ©2016 AACR.
Data from Identification of TRIML2, a Novel p53 Target, that Enhances p53 SUMOylation and Regulates the Transactivation of Proapoptotic Genes
Authors: Kung Che-Pei , Khaku Sakina , Jennis Matthew , Zhou Yan , Murphy Maureen E.
Published: March 2024

Abstract
The tumor-suppressor protein p53, encoded by TP53, inhibits tumorigenesis by inducing cell-cycle arrest, senescence, and apoptosis. Several genetic polymorphisms exist in TP53, including a proline to arginine variant at amino acid 72 (P72 and R72, respectively); this polymorphism alters p53 function. In general, the P72 variant shows increased ability to induce cell-cycle arrest, whereas the R72 variant possesses increased ability to induce apoptosis, relative to P72. At present, the underlying mechanisms for these functional differences are not fully understood. Toward elucidating the molecular basis for these differences, a gene-expression microarray analysis was conducted on normal human fibroblast cells that are homozygous for P72 and R72 variants, along with subclones of these lines that express a p53 short hairpin (shp53). Approximately three dozen genes were identified whose transactivation is affected by the codon 72 polymorphism. One of these is the tripartite-motif family-like 2 (TRIML2) gene, which is preferentially induced by the R72 variant. Importantly, the accumulated data indicate that TRIML2 interacts with p53, and facilitates the modification of p53 with SUMO2. TRIML2 also enhances the ability of p53 to transactivate a subset of proapoptotic target genes associated with prolonged oxidative stress, including PIDD, PIG3 (TP53I3), and PIG6 (PRODH). These data indicate that TRIML2 is part of a feed-forward loop that activates p53 in cells expressing the R72 variant, particularly after prolonged stress.

Implications: The defined actions of TRIML2, in part, explain the underlying molecular basis for increased apoptotic potential of the R72 variant of p53. Mol Cancer Res; 13(2); 250–62. ©2014 AACR.
Data from Tumor Suppressor NF2 Blocks Cellular Migration by Inhibiting Ectodomain Cleavage of CD44
Authors: Hartmann Monika , Parra Liseth M. , Ruschel Anne , Böhme Sandra , Li Yong , Morrison Helen , Herrlich Andreas , Herrlich Peter
Published: March 2024

Abstract
Ectodomain cleavage (shedding) of transmembrane proteins by metalloproteases (MMP) generates numerous essential signaling molecules, but its regulation is not totally understood. CD44, a cleaved transmembrane glycoprotein, exerts both antiproliferative or tumor-promoting functions, but whether proteolysis is required for this is not certain. CD44-mediated contact inhibition and cellular proliferation are regulated by counteracting CD44 C-terminal interacting proteins, the tumor suppressor protein merlin (NF2) and ERM proteins (ezrin, radixin, moesin). We show here that activation or overexpression of constitutively active merlin or downregulation of ERMs inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced [as well as serum, hepatocyte growth factor (HGF), or platelet-derived growth factor (PDGF)] CD44 cleavage by the metalloprotease ADAM10, whereas overexpressed ERM proteins promoted cleavage. Merlin- and ERM-modulated Ras or Rac activity was not required for this function. However, latrunculin (an actin-disrupting toxin) or an ezrin mutant which is unable to link CD44 to actin, inhibited CD44 cleavage, identifying a cytoskeletal C-terminal link as essential for induced CD44 cleavage. Cellular migration, an important tumor property, depended on CD44 and its cleavage and was inhibited by merlin. These data reveal a novel function of merlin and suggest that CD44 cleavage products play a tumor-promoting role. Neuregulin, an EGF ligand released by ADAM17 from its pro-form NRG1, is predominantly involved in regulating cellular differentiation. In contrast to CD44, release of neuregulin from its pro-form was not regulated by merlin or ERM proteins. Disruption of the actin cytoskeleton however, also inhibited NRG1 cleavage. This current study presents one of the first examples of substrate-selective cleavage regulation.

Implications: Investigating transmembrane protein cleavage and their regulatory pathways have provided new molecular insight into their important role in cancer formation and possible treatment. Mol Cancer Res; 13(5); 879–90. ©2015 AACR.
Data from Phosphoproteomics Reveals MAPK Inhibitors Enhance MET- and EGFR-Driven AKT Signaling in KRAS-Mutant Lung Cancer
Authors: Kim Jae-Young , Welsh Eric A. , Fang Bin , Bai Yun , Kinose Fumi , Eschrich Steven A. , Koomen John M. , Haura Eric B.
Published: March 2024

Abstract
Pathway inhibition of the RAS-driven MAPK pathway using small-molecule kinase inhibitors has been a key focus for treating cancers driven by oncogenic RAS, yet significant clinical responses are lacking. Feedback reactivation of ERK driven by drug-induced RAF activity has been suggested as one of the major drug resistance mechanisms, especially in the context of oncogenic RAS. To determine whether additional adaptive resistance mechanisms may coexist, we characterized global phosphoproteomic changes after MEK inhibitor selumetinib (AZD6244) treatment in KRAS-mutant A427 and A549 lung adenocarcinoma cell lines employing mass spectrometry–based phosphoproteomics. We identified 9,075 quantifiable unique phosphosites (corresponding to 3,346 unique phosphoproteins), of which 567 phosphosites were more abundant and 512 phosphosites were less abundant after MEK inhibition. Selumetinib increased phosphorylation of KSR-1, a scaffolding protein required for assembly of MAPK signaling complex, as well as altered phosphorylation of GEF-H1, a novel regulator of KSR-1 and implicated in RAS-driven MAPK activation. Moreover, selumetinib reduced inhibitory serine phosphorylation of MET at Ser985 and potentiated HGF- and EGF-induced AKT phosphorylation. These results were recapitulated by pan-RAF (LY3009120), MEK (GDC0623), and ERK (SCH772984) inhibitors, which are currently under early-phase clinical development against RAS-mutant cancers. Our results highlight the unique adaptive changes in MAPK scaffolding proteins (KSR-1, GEF-H1) and in RTK signaling, leading to enhanced PI3K–AKT signaling when the MAPK pathway is inhibited.

Implications: This study highlights the unique adaptive changes in MAPK scaffolding proteins (KSR-1, GEF-H1) and in RTK signaling, leading to enhanced PI3K/AKT signaling when the MAPK pathway is inhibited. Mol Cancer Res; 14(10); 1019–29. ©2016 AACR.
Data from VDR Status Arbitrates the Prometastatic Effects of Tumor-Associated Macrophages
Authors: Zhang Yan , Guo Quanjun , Zhang Zhujun , Bai Nan , Liu Ze , Xiong Min , Wei Yuquan , Xiang Rong , Tan Xiaoyue
Published: March 2024

Abstract
The relationship between tumor-associated macrophages (TAM) and epithelial-to-mesenchymal transition (EMT) during the initiation and progression of metastasis is still unclear. Here, a role for the vitamin D receptor (VDR) in metastasis was identified, as well as a role in the relationship between TAMs and EMT. First, the expression level of VDR was examined in clinical tissue from human patients with breast cancer or a mouse model of breast cancer with differential metastasis. These results revealed that VDR expression negatively correlates with metastasis in breast cancer. Second, coculture of VDR-overexpressing breast cancer cells with a macrophage cell line demonstrated that overexpression of VDR alleviated the prometastatic effect of cocultured macrophages on breast cancer cells. Furthermore, VDR overexpression abrogated the induction of EMT in breast cancer cells by cocultured macrophage cells, as measured by a loss of E-cadherin (CDH1) and induction of α-smooth muscle actin (α-SMA). TNFα in macrophage conditioned media inhibited VDR expression, whereas downregulation of VDR further mediated the promotion of TGFβ-induced EMT by TNFα. In addition, β-catenin expression was inhibited in VDR-overexpressing breast cancer cells and tumor xenografts. Finally, administration of calcitriol [1,25-(OH)2D3], an active vitamin D metabolite, exerted similar antimetastatic effects in breast cancer cells in vitro and a mouse model of breast cancer in vivo with preservation of VDR and suppression of β-catenin.

Implications: VDR suppression by TNFα mediates the prometastatic effect of TAMs through enhancement of the β-catenin pathway. Mol Cancer Res; 12(8); 1181–91. ©2014 AACR.
Data from COX-2 Elevates Oncogenic miR-526b in Breast Cancer by EP4 Activation
Authors: Majumder Mousumi , Landman Erin , Liu Ling , Hess David , Lala Peeyush K.
Published: March 2024

Abstract
MicroRNAs (miRs) are small regulatory molecules emerging as potential biomarkers in cancer. Previously, it was shown that COX-2 expression promotes breast cancer progression via multiple mechanisms, including induction of stem-like cells (SLC), owing to activation of the prostaglandin E2 receptor EP4 (PTGER4). COX-2 overexpression also upregulated microRNA-526b (miR-526b), in association with aggressive phenotype. Here, the functional roles of miR-526b in breast cancer and the mechanistic role of EP4 signaling in miR-526b upregulation were examined. A positive correlation was noted between miR-526b and COX-2 mRNA expression in COX-2 disparate breast cancer cell lines. Stable overexpression of miR-526b in poorly metastatic MCF7 and SKBR3 cell lines resulted in increased cellular migration, invasion, EMT phenotype and enhanced tumorsphere formation in vitro, and lung colony formation in vivo in immunodeficient mice. Conversely, knockdown of miR-526b in aggressive MCF7-COX-2 and SKBR3-COX-2 cells reduced oncogenic functions and reversed the EMT phenotype, in vitro. Furthermore, it was determined that miR-526b expression is dependent on EP4 receptor activity and downstream PI3K–AKT and cyclic AMP (cAMP) signaling pathways. PI3K–AKT inhibitors blocked EP4 agonist–mediated miR-526b upregulation and tumorsphere formation in MCF7 and SKBR3 cells. NF-κB inhibitor abrogates EP agonist–stimulated miRNA expression in MCF7 and T47D cells, indicating that the NF-κB pathway is also involved in miR-526b regulation. In addition, inhibition of COX-2, EP4, PI3K, and PKA in COX-2–overexpressing cells downregulated miR-526b and its functions in vitro. Finally, miR-526b expression was significantly higher in cancerous than in noncancerous breast tissues and associated with reduced patient survival. In conclusion, miR-526b promotes breast cancer progression, SLC-phenotype through EP4-mediated signaling, and correlates with breast cancer patient survival.

Implications: This study presents novel findings that miRNA 526b is a COX-2 upregulated, oncogenic miRNA promoting SLCs, the expression of which follows EP4 receptor-mediated signaling, and is a promising biomarker for monitoring and personalizing breast cancer therapy. Mol Cancer Res; 13(6); 1022–33. ©2015 AACR.
Data from NME2 Is a Master Suppressor of Apoptosis in Gastric Cancer Cells via Transcriptional Regulation of miR-100 and Other Survival Factors
Authors: Gong Yi , Yang Geng , Wang Qizhi , Wang Yumeng , Zhang Xiaobo
Published: March 2024

Abstract
Tumorigenesis is a result of uncontrollable cell proliferation which is regulated by a variety of complex factors including miRNAs. The initiation and progression of cancer are always accompanied by the dysregulation of miRNAs. However, the underlying mechanism of miRNA dysregulation in cancers is still largely unknown. Herein we found that miR-100 was inordinately upregulated in the sera of patients with gastric cancer, indicating that miR-100 might emerge as a biomarker for the clinical diagnosis of cancer. The abnormal expression of miR-100 in gastric cancer cells was mediated by a novel transcription factor NME2 (NME/NM23 nucleoside diphosphate kinase 2). Further data revealed that the transcription factor NME2 could promote the transcriptions of antiapoptotic genes including miRNA (i.e., miR-100) and protein-encoding genes (RIPK1, STARD5, and LIMS1) through interacting with RNA polymerase II and RNA polymerase II–associated protein 2 to mediate the phosphorylation of RNA polymerase II C-terminal domain at the 5th serine, leading to the suppression of apoptosis of gastric cancer cells both in vitro and in vivo. In this context, our study revealed that the transcription factor NME2 is a master suppressor for apoptosis of gastric cancer cells.
Implications:
Our study contributed novel insights into the mechanism involved in the expression regulation of apoptosis-associated genes and provided a potential biomarker of gastric cancer.
Data from TGFβ and Hippo Pathways Cooperate to Enhance Sarcomagenesis and Metastasis through the Hyaluronan-Mediated Motility Receptor (HMMR)
Authors: Ye Shuai , Liu Ying , Fuller Ashley M. , Katti Rohan , Ciotti Gabrielle E. , Chor Susan , Alam Md. Zahidul , Devalaraja Samir , Lorent Kristin , Weber Kristy , Haldar Malay , Pack Michael A. , Eisinger-Mathason T.S. Karin
Published: March 2024

Abstract
High-grade sarcomas are metastatic and pose a serious threat to patient survival. Undifferentiated pleomorphic sarcoma (UPS) is a particularly dangerous and relatively common sarcoma subtype diagnosed in adults. UPS contains large quantities of extracellular matrix (ECM) including hyaluronic acid (HA), which is linked to metastatic potential. Consistent with these observations, expression of the HA receptor, hyaluronan-mediated motility receptor (HMMR/RHAMM), is tightly controlled in normal tissues and upregulated in UPS. Moreover, HMMR expression correlates with poor clinical outcome in these patients. Deregulation of the tumor-suppressive Hippo pathway is also linked to poor outcome in these patients. YAP1, the transcriptional regulator and central effector of Hippo pathway, is aberrantly stabilized in UPS and was recently shown to control RHAMM expression in breast cancer cells. Interestingly, both YAP1 and RHAMM are linked to TGFβ signaling. Therefore, we investigated crosstalk between YAP1 and TGFβ resulting in enhanced RHAMM-mediated cell migration and invasion. We observed that HMMR expression is under the control of both YAP1 and TGFβ and can be effectively targeted with small-molecule approaches that inhibit these pathways. Furthermore, we found that RHAMM expression promotes tumor cell proliferation and migration/invasion. To test these observations in a robust and quantifiable in vivo system, we developed a zebrafish xenograft assay of metastasis, which is complimentary to our murine studies. Importantly, pharmacologic inhibition of the TGFβ–YAP1–RHAMM axis prevents vascular migration of tumor cells to distant sites.
Implications:
These studies reveal key metastatic signaling mechanisms and highlight potential approaches to prevent metastatic dissemination in UPS.YAP1 and TGFβ cooperatively enhance proliferation and migration/invasion of UPS and fibrosarcomas.
Data from Aberrant LPL Expression, Driven by STAT3, Mediates Free Fatty Acid Metabolism in CLL Cells
Authors: Rozovski Uri , Grgurevic Srdana , Bueso-Ramos Carlos , Harris David M. , Li Ping , Liu Zhiming , Wu Ji Yuan , Jain Preetesh , Wierda William , Burger Jan , O'Brien Susan , Jain Nitin , Ferrajoli Alessandra , Keating Michael J. , Estrov Zeev
Published: March 2024

Abstract
While reviewing chronic lymphocytic leukemia (CLL) bone marrow slides, we identified cytoplasmic lipid vacuoles in CLL cells but not in normal B cells. Because lipoprotein lipase (LPL), which catalyzes hydrolysis of triglycerides into free fatty acids (FFA), is aberrantly expressed in CLL, we investigated whether LPL regulates the oxidative metabolic capacity of CLL cells. We found that unlike normal B cells, CLL cells metabolize FFAs. Because STAT3 is constitutively activated in CLL cells and because we identified putative STAT3 binding sites in the LPL promoter, we sought to determine whether STAT3 drives the aberrant expression of LPL. Transfection of luciferase reporter gene constructs driven by LPL promoter fragments into MM1 cells revealed that STAT3 activates the LPL promoter. In addition, chromatin immunoprecipitation confirmed that STAT3 binds to the LPL promoter. Furthermore, transfection of CLL cells with STAT3-shRNA downregulated LPL transcripts and protein levels, confirming that STAT3 activates the LPL gene. Finally, transfection of CLL cells with LPL-siRNAs decreased the capacity of CLL cells to oxidize FFAs and reduced cell viability.

Implications: Our study suggests that CLL cells adopt their metabolism to oxidize FFA. Activated STAT3 induces LPL, which catalyzes the hydrolysis of triglycerides into FFA. Therefore, inhibition of STAT3 is likely to prevent the capacity of CLL cells to utilize FFA. Mol Cancer Res; 13(5); 944–53. ©2015 AACR.
Data from αvβ3 Integrin Mediates Radioresistance of Prostate Cancer Cells through Regulation of Survivin
Authors: Wang Tao , Huang Jiayi , Vue Mai , Alavian Michael R. , Goel Hira Lal , Altieri Dario C. , Languino Lucia R. , FitzGerald Thomas J.
Published: March 2024

Abstract
The αvβ3 integrin is involved in various physiologic and pathologic processes such as wound healing, angiogenesis, tumor growth, and metastasis. The impact of αvβ3 integrin on the radiosensitivity of prostate cancer cells and the molecular mechanism controlling cell survival in response to ionizing radiation (IR) was investigated. Both LNCaP cells stably transfected with αvβ3 integrin and PC-3 cells that contain endogenous β3 integrin were used. This study demonstrated that αvβ3 integrin increases survival of αvβ3-LNCaP cells upon IR while small hairpin RNA (shRNA)-mediated knockdown of αvβ3 integrin in PC-3 cells sensitizes to radiation. Expression of αvβ3 integrin in LNCaP cells also enhances anchorage-independent cell growth while knockdown of αvβ3 integrin in PC-3 cells inhibits anchorage-independent cell growth. The αvβ3 antagonist, cRGD, significantly increases radiosensitivity in both αvβ3-LNCaP and PC-3 cells. Moreover, αvβ3 integrin prevents radiation-induced downregulation of survivin. Inhibition of survivin expression by siRNA or shRNA enhances IR-induced inhibition of anchorage-independent cell growth. Overexpression of wild-type survivin in PC-3 cells treated with αvβ3 integrin shRNA increases survival of cells upon IR. These findings reveal that αvβ3 integrin promotes radioresistance and regulates survivin levels in response to IR.
Implications:
Future translational research on targeting αvβ3 integrin and survivin may reveal novel approaches as an adjunct to radiotherapy for patients with prostate cancer.
Data from NRF2-Driven KEAP1 Transcription in Human Lung Cancer
Authors: Tian Yijun , Liu Qian , Yu Shengnan , Chu Qian , Chen Yuan , Wu Kongming , Wang Liang
Published: March 2024

Abstract
Constitutive NRF2 activation by disrupted KEAP1-NRF2 interaction has been reported in a variety of human cancers. However, studies focusing on NRF2-driven KEAP1 expression under human cancer contexts are still uncommon. We examined mRNA expression correlation between NRF2 and KEAP1 in multiple human cancers. We measured KEAP1 mRNA and protein alterations in response to the activation or silencing of NRF2. We queried chromatin immunoprecipitation sequencing (ChIP-seq) datasets to identify NRF2 binding to KEAP1 promoters in human cells. We used reporter assay and CRISPR editing to assess KEAP1 promoter activity and mRNA abundance change. To determine specimen implication of the feedback pattern, we used gene expression ratio to predict NRF2 signal disruption as well as patients' prognosis. Correlation analysis showed KEAP1 mRNA expression was in positive association with NRF2 in multiple squamous cell cancers. The positive correlations were consistent across all squamous cell lung cancer cohorts, but not in adenocarcinomas. In human lung cells, NRF2 interventions significantly altered KEAP1 mRNA and protein expressions. ChIP-quantitative PCR (ChIP-qPCR) and sequencing data demonstrated consistent NRF2 occupancy to KEAP1 promoter. Deleting NRF2 binding site significantly reduced baseline and inducible KEAP1 promoter activity and KEAP1 mRNA expression. By incorporating tumor tissue KEAP1 mRNA expressions in estimating NRF2 signaling disruptions, we found increased TXN/KEAP1 mRNA ratio in cases with NRF2 gain or KEAP1 loss and decreased NRF2/KEAP1 mRNA ratio in cases with NRF2–KEAP1 somatic mutations. In TCGA PanCancer datasets, we also identified that cases with loss-of-function mutations in NRF2 pathway recurrently appeared above the NRF2-KEAP1 mRNA expression regression lines. Moreover, compared with previous NRF2 signatures, the ratio-based strategy showed better predictive performance in survival analysis with multiple squamous cell lung cancer cohort validations.
Implications:
NRF2-driven KEAP1 transcription is a crucial component of NRF2 signaling modulation. This hidden circuit will provide in-depth insight into novel cancer prevention and therapeutic strategies.