bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Mutual Exclusivity Analysis of Genetic and Epigenetic Drivers in Melanoma Identifies a Link Between p14ARF and RARβ Signaling
Authors: Dahl Christina , Christensen Claus , Jönsson Göran , Lorentzen Anders , Skjødt Mette Louise , Borg Åke , Pawelec Graham , Guldberg Per
Published: April 2023

Abstract
Melanoma genomes contain thousands of alterations including: mutations, copy number alterations, structural aberrations, and methylation changes. The bulk of this variation is stochastic and functionally neutral, with only a small minority representing “drivers” that contribute to the genesis and maintenance of tumors. Drivers are often directly or inversely correlated across tumors, reflecting the molecular and regulatory signaling pathways in which they operate. Here, a profile of genetic and epigenetic drivers in 110 human melanoma cell lines was generated and searched for non-random distribution patterns. Statistically significant mutual exclusivity was revealed among components of each of the p16INK4A-CDK4-RB, RAS-RAF-MEK-ERK and PI3K-AKT signaling pathways. In addition, an inverse correlation was observed between promoter hypermethylation of retinoic acid receptor β (RARB) and CDKN2A alterations affecting p14ARF (P < 0.0001), suggesting a functional link between RARβ signaling and the melanoma-suppressive activities of p14ARF. Mechanistically, all-trans retinoic acid (ATRA) treatment increased the expression of p14ARF in primary human melanocytes and the steady-state levels of p14ARF in these cells were shown to be regulated via RARβ. Furthermore, the ability of ATRA to induce senescence is reduced in p14ARF-depleted melanocytes, and we provide proof-of-concept that ATRA can induce irreversible growth arrest in melanoma cells with an intact RARβ-p14ARF signaling axis, independent of p16INK4A and p53 status.

Implications: These data highlight the power of mutual exclusivity analysis of cancer drivers to unravel molecular pathways and establish a previously unrecognized cross-talk between RARβ and p14ARF with potential implications for melanoma treatment. Mol Cancer Res; 11(10); 1166–78. ©2013 AACR.
Data from AURKA Governs Self-Renewal Capacity in Glioma-Initiating Cells via Stabilization/Activation of β-catenin/Wnt Signaling
Authors: Xia Zhibo , Wei Ping , Zhang Heng , Ding Zhiming , Yang Lixuan , Huang Zhengsong , Zhang Nu
Published: April 2023

Abstract
Glioma-initiating cells (GIC), which are characterized by their self-renewal capacity and tumorigenicity, were recently identified as a highly tumorigenic subpopulation of glioblastoma multiforme and are considered responsible for glioblastoma recurrence and chemo/radiation resistance. Previously, it was revealed that Wnt signaling activation is critical to the self-renewal of GICs. However, the molecular mechanism underlying the high expression of β-catenin, the key transcription factor of the Wnt signaling pathway, remains elusive. In this investigation, it was determined that aurora kinase A (AURKA) regulates the self-renewal and tumorigenicity of GICs by stabilizing β-catenin. In GICs, AURKA directly interacts with AXIN and disrupts the AXIN/GSK3β/β-catenin destruction complex and stabilizes β-catenin, thereby activating Wnt signaling to promote self-renewal. Stable knockdown of AURKA destabilizes β-catenin by increasing phosphorylated β-catenin bound to AXIN and suppresses Wnt signaling, which inhibits the ability of GICs to self-renew. This effect is rescued by expression of an AURKA kinase dead mutant, D274A, which lacks the ability to phosphorylate GSK3β, indicating that stabilization of β-catenin by AURKA in GICs is independent from phosphorylation of GSK3β. Functional experiments confirm that inhibition of AUKRA in GICs could suppress their “stemness,” self-renewal ability, and tumorigenicity both in vitro and in vivo, and these effects could be rescued by stabilized β-catenin mutant. These findings indicate that AURKA competes away the binding of AXIN from β-catenin, induces β-catenin stabilization, and activates Wnt signaling in GICs.

Implications: AURKA kinase inhibition could effectively attenuate Wnt signaling, thereby inhibiting the self-renewal and tumorigenicity of GICs, and may be a novel target for glioblastoma treatment strategies. Mol Cancer Res; 11(9); 1101–11. ©2013 AACR.
Data from Unraveling the Role of FOXQ1 in Colorectal Cancer Metastasis
Authors: Abba Mohammed , Patil Nitin , Rasheed Kabeer , Nelson Laura D. , Mudduluru Giridhar , Leupold Jörg Hendrik , Allgayer Heike
Published: April 2023

Abstract
Malignant cell transformation, invasion, and metastasis are dependent on the coordinated rewiring of gene expression. A major component in the scaffold of these reprogramming events is one in which epithelial cells lose intercellular connections and polarity to adopt a more motile mesenchymal phenotype, which is largely supported by a robust transcriptional machinery consisting mostly of developmental transcription factors. This study demonstrates that the winged helix transcription factor, FOXQ1, contributes to this rewiring process, in part by directly modulating the transcription of TWIST1, itself a key mediator of metastasis that transcriptionally regulates the expression of important molecules involved in epithelial-to-mesenchymal transition. Forced expression and RNA-mediated silencing of FOXQ1 led to enhanced and suppressed mRNA and protein levels of TWIST1, respectively. Mechanistically, FOXQ1 enhanced the reporter activity of TWIST1 and directly interacted with its promoter. Furthermore, enhanced expression of FOXQ1 resulted in increased migration and invasion in colorectal cancer cell lines, whereas knockdown studies showed the opposite effect. Moreover, using the in vivo chicken chorioallantoic membrane metastasis assay model, FOXQ1 significantly enhanced distant metastasis with minimal effects on tumor growth.

Implications: These findings reveal FOXQ1 as a modulator of TWIST1-mediated metastatic phenotypes and support its potential as a biomarker of metastasis. Mol Cancer Res; 11(9); 1017–28. ©2013 AACR.
Data from Downregulation of HOPX Controls Metastatic Behavior in Sarcoma Cells and Identifies Genes Associated with Metastasis
Authors: Kovářová Denisa , Plachý Jiří , Kosla Jan , Trejbalová Kateřina , Čermák Vladimír , Hejnar Jiří
Published: April 2023

Abstract
Comparing the gene expression profiles of metastatic and nonmetastatic cells has the power to reveal candidate metastasis-associated genes, whose involvement in metastasis can be experimentally tested. In this study, differentially expressed genes were explored in the v-src-transformed metastatic cell line PR9692 and its nonmetastatic subclone PR9692-E9. First, the contribution of homeodomain only protein X (HOPX) in metastasis formation and development was assessed. HOPX-specific knockdown decreased HOPX expression in the nonmetastatic subclone and displayed reduced cell motility in vitro. Critically, HOPX knockdown decreased the in vivo metastatic capacity in a syngeneic animal model system. Genomic analyses identified a cadre of genes affected by HOPX knockdown that intersected significantly with genes previously found to be differentially expressed in metastatic versus nonmetastatic cells. Furthermore, 232 genes were found in both screens with at least a two-fold change in gene expression, and a number of high-confidence targets were validated for differential expression. Importantly, significant changes were demonstrated in the protein expression level of three metastatic-associated genes (NCAM, FOXG1, and ITGA4), and knockdown of one of the identified HOPX-regulated metastatic genes, ITGA4, showed marked inhibition of cell motility and metastasis formation. These data demonstrate that HOPX is a metastasis-associated gene and that its knockdown decreases the metastatic activity of v-src-transformed cells through altered gene expression patterns.

Implications: This study provides new mechanistic insight into a HOPX-regulated metastatic dissemination signature. Mol Cancer Res; 11(10); 1235–47. ©2013 AACR.
Data from T-Type Ca2+ Channel Inhibition Induces p53-Dependent Cell Growth Arrest and Apoptosis through Activation of p38-MAPK in Colon Cancer Cells
Authors: Dziegielewska Barbara , Brautigan David L. , Larner James M. , Dziegielewski Jaroslaw
Published: April 2023

Abstract
Epithelial tumor cells express T-type Ca2+ channels, which are thought to promote cell proliferation. This study investigated the cellular response to T-type Ca2+ channel inhibition either by small-molecule antagonists or by RNAi-mediated knockdown. Selective T-type Ca2+ channel antagonists caused growth inhibition and apoptosis more effectively in HCT116 cells expressing wild-type p53 (p53wt), than in HCT116 mutant p53−/− cells. These antagonists increased p53-dependent gene expression and increased genomic occupancy of p53 at specific target sequences. The knockdown of a single T-type Ca2+ channel subunit (CACNA1G) reduced cell growth and induced caspase-3/7 activation in HCT116 p53wt cells as compared with HCT116 mutant p53−/− cells. Moreover, CaCo2 cells that do not express functional p53 were made more sensitive to CACNA1G knockdown when p53wt was stably expressed. Upon T-type Ca2+ channel inhibition, p38-MAPK promoted phosphorylation at Ser392 of p53wt. Cells treated with the inhibitor SB203580 or specific RNAi targeting p38-MAPKα/β (MAPK14/MAPK11) showed resistance to T-type Ca2+ channel inhibition. Finally, the decreased sensitivity to channel inhibition was associated with decreased accumulation of p53 and decreased expression of p53 target genes, p21Cip1 (CDKN1A) and BCL2-binding component 3 (BBC3/PUMA).

Implications: A novel pathway involving p53 and p38-MAPK is revealed and provides a rationale for antitumor therapies that target T-type Ca2+ channels. Mol Cancer Res; 12(3); 348–58. ©2013 AACR.
Data from A Novel Regulatory Mechanism of Pim-3 Kinase Stability and Its Involvement in Pancreatic Cancer Progression
Authors: Zhang Fei , Liu Bin , Wang Zhen , Yu Xian-Jun , Ni Quan-Xing , Yang Wen-Tao , Mukaida Naofumi , Li Ying-Yi
Published: April 2023

Abstract
Translationally controlled tumor protein (TCTP/TPT1) was identified from a yeast 2-hybrid screen and shown to interact with Pim-3, a member of the proto-oncogene Pim family with serine/threonine kinase activity. TCTP was aberrantly expressed in human pancreatic cancer cells and malignant ductal epithelial cells, but not in normal pancreatic duct epithelial cells adjacent to tumor foci of human pancreatic cancer tissue. Moreover, TCTP colocalized with Pim-3 both in human pancreatic cancer cells and in clinical tissues. Mapping studies revealed that the interaction between Pim-3 and TCTP occurred through the C-terminal region of Pim-3 and N-terminal region of TCTP. Although Pim-3 had no effect on TCTP expression or phosphorylation, overexpression of TCTP increased the amount of Pim-3 in a dose-dependent manner. Interestingly, RNAi-mediated ablation of TCTP expression reduced Pim-3 protein but not mRNA, through a mechanism involving the ubiquitin–proteasome degradation system. As a consequence of Pim-3 instability and subsequent degradation, tumor growth in vitro and in vivo was inhibited by arresting cell-cycle progression and enhancing apoptosis. Furthermore, TCTP and Pim-3 expression were significantly correlated in pancreatic adenocarcinoma specimens, and patients with highly expressed TCTP and Pim-3 presented with a more advanced tumor stage. These observations indicate that TCTP enhances Pim-3 stability to simultaneously promote and prevent cell-cycle progression and apoptosis, respectively. Hence, TCTP and Pim-3 serve a pivotal role in human pancreatic cancer with important ramifications for clinical diagnostic and therapeutic implications.

Implications: The present study provides a new idea and experimental evidence for recognizing TCTP/Pim-3 pathway as a target for therapy in human pancreatic cancer. Mol Cancer Res; 11(12); 1508–20. ©2013 AACR.
Data from PKCι Maintains a Tumor-initiating Cell Phenotype That Is Required for Ovarian Tumorigenesis
Authors: Wang Yin , Hill Kristen S. , Fields Alan P.
Published: April 2023

Abstract
Protein kinase Cι (PKCι) has oncogenic potential and is an attractive therapeutic target for treatment of lung cancer, particularly those tumors that express elevated PKCι. However, whether PKCι is a viable target in ovarian cancer is unknown, and virtually nothing is known about the mechanism by which PKCι drives ovarian tumorigenesis. Here, it is demonstrated that PKCι maintains a tumor-initiating cell (TIC) phenotype that drives ovarian tumorigenesis. A highly tumorigenic population of cells from human ovarian cancer cell lines exhibit cancer stem-like TIC properties, including self-renewal, clonal expansion, expression of stem-related genes, enhanced transformed growth in vitro, and aggressive tumor-initiating activity in vivo. Genetic disruption of PKCι inhibits the proliferation, clonal expansion, anchorage-independent growth, and enhanced tumorigenic properties of ovarian TICs. Biochemical analysis demonstrates that PKCι acts through its oncogenic partner Ect2 to activate a MEK/ERK signaling axis that drives the ovarian TIC phenotype. Genomic analysis reveals that PKCι and Ect2 are coordinately amplified and overexpressed in the majority of primary ovarian serous tumors, and these tumors exhibit evidence of an active PKCι-Ect2 signaling axis in vivo. Finally, this study reveals that auranofin, a potent and selective inhibitor of oncogenic PKCι signaling, inhibits the tumorigenic properties of ovarian TIC cells in vitro and in vivo. These data demonstrate that PKCι is required for a TIC phenotype in ovarian cancer, and that auranofin is an attractive therapeutic option to target deadly ovarian TICs in ovarian cancer patients.

Implications: PKCι drives a tumor-initiating cell phenotype in ovarian cancer cells that can be therapeutically targeted with auranofin, a small molecule inhibitor of PKCι signaling. Mol Cancer Res; 11(12); 1624–35. ©2013 AACR.
Data from The HER2- and Heregulin β1 (HRG)–Inducible TNFR Superfamily Member Fn14 Promotes HRG-Driven Breast Cancer Cell Migration, Invasion, and MMP9 Expression
Authors: Asrani Kaushal , Keri Ruth A. , Galisteo Rebeca , Brown Sharron A.N. , Morgan Sarah J. , Ghosh Arundhati , Tran Nhan L. , Winkles Jeffrey A.
Published: April 2023

Abstract
HER2 overexpression occurs in 15% to 20% of all breast cancers and is associated with increased metastatic potential and poor patient survival. Abnormal HER2 activation, either through HER2 overexpression or heregulin (HRG):HER3 binding, elicits the formation of potent HER2–HER3 heterodimers and drives breast cancer cell growth and metastasis. In a previous study, we found that fibroblast growth factor-inducible 14 (Fn14), a member of the TNF receptor superfamily, was frequently overexpressed in human HER2+ breast tumors. We report here that HER2 and Fn14 are also coexpressed in mammary tumors that develop in two different transgenic mouse models of breast cancer. In consideration of these findings, we investigated whether HER2 activation in breast cancer cells could directly induce Fn14 gene expression. We found that transient or stable transfection of MCF7 cells with a HER2 expression plasmid increased Fn14 protein levels. Also, HRG1-β1 treatment of MCF7 cells transiently induced Fn14 mRNA and protein expression. Both the HER2- and HRG1-β1–induced increase in Fn14 expression in MCF7 cells as well as basal Fn14 expression in HER2 gene-amplified AU565 cells could be reduced by HER2 kinase inhibition with lapatinib or combined HER2 and HER3 depletion using siRNA. We also report that Fn14-depleted, HER2-overexpressing MCF7 cells have reduced basal cell migration capacity and reduced HRG1-β1–stimulated cell migration, invasion, and matrix metalloproteinase (MMP)-9 expression. Together, these results indicate that Fn14 may be an important downstream regulator of HER2/HER3–driven breast cancer cell migration and invasion. Mol Cancer Res; 11(4); 393–404. ©2013 AACR.
Data from Dual Src Kinase/Pretubulin Inhibitor KX-01, Sensitizes ERα-negative Breast Cancers to Tamoxifen through ERα Reexpression
Authors: Anbalagan Muralidharan , Sheng Mei , Fleischer Brian , Zhang Yifang , Gao Yuanjun , Hoang Van , Matossian Margarite , Burks Hope E. , Burow Matthew E. , Collins-Burow Bridgette M. , Hangauer David , Rowan Brian G.
Published: April 2023

Abstract
Unlike breast cancer that is positive for estrogen receptor-α (ERα), there are no targeted therapies for triple-negative breast cancer (TNBC). ERα is silenced in TNBC through epigenetic changes including DNA methylation and histone acetylation. Restoring ERα expression in TNBC may sensitize patients to endocrine therapy. Expression of c-Src and ERα are inversely correlated in breast cancer suggesting that c-Src inhibition may lead to reexpression of ERα in TNBC. KX-01 is a peptide substrate–targeted Src/pretubulin inhibitor in clinical trials for solid tumors. KX-01 (1 mg/kg body weight-twice daily) inhibited growth of tamoxifen-resistant MDA-MB-231 and MDA-MB-157 TNBC xenografts in nude mice that was correlated with Src kinase inhibition. KX-01 also increased ERα mRNA and protein, as well as increased the ERα targets progesterone receptor (PR), pS2 (TFF1), cyclin D1 (CCND1), and c-myc (MYC) in MDA-MB-231 and MDA-MB-468, but not MDA-MB-157 xenografts. MDA-MB-231 and MDA-MB-468 tumors exhibited reduction in mesenchymal markers (vimentin, β-catenin) and increase in epithelial marker (E-cadherin) suggesting mesenchymal-to-epithelial transition (MET). KX-01 sensitized MDA-MB-231 and MDA-MB-468 tumors to tamoxifen growth inhibition and tamoxifen repression of the ERα targets pS2, cyclin D1, and c-myc. Chromatin immunoprecipitation (ChIP) of the ERα promoter in KX-01–treated tumors demonstrated enrichment of active transcription marks (acetyl-H3, acetyl-H3Lys9), dissociation of HDAC1, and recruitment of RNA polymerase II. Methylation-specific PCR and bisulfite sequencing demonstrated no alteration in ERα promoter methylation by KX-01. These data demonstrate that in addition to Src kinase inhibition, peptidomimetic KX-01 restores ERα expression in TNBC through changes in histone acetylation that sensitize tumors to tamoxifen.

Implications: Src kinase/pretubulin inhibitor KX-01 restores functional ERα expression in ERα– breast tumors, a novel treatment strategy to treat triple-negative breast cancer. Mol Cancer Res; 15(11); 1491–502. ©2017 AACR.
Data from Kinesin Family Deregulation Coordinated by Bromodomain Protein ANCCA and Histone Methyltransferase MLL for Breast Cancer Cell Growth, Survival, and Tamoxifen Resistance
Authors: Zou June X. , Duan Zhijian , Wang Junjian , Sokolov Alex , Xu Jianzhen , Chen Christopher Z. , Li Jian Jian , Chen Hong-Wu
Published: April 2023

Abstract
Kinesins are a superfamily of motor proteins and often deregulated in different cancers. However, the mechanism of their deregulation has been poorly understood. Through examining kinesin gene family expression in estrogen receptor (ER)-positive breast cancer cells, we found that estrogen stimulation of cancer cell proliferation involves a concerted regulation of specific kinesins. Estrogen strongly induces expression of 19 kinesin genes such as Kif4A/4B, Kif5A/5B, Kif10, Kif11, Kif15, Kif18A/18B, Kif20A/20B, Kif21, Kif23, Kif24, Kif25, and KifC1, whereas suppresses the expression of seven others, including Kif1A, Kif1C, Kif7, and KifC3. Interestingly, the bromodomain protein ANCCA/ATAD2, previously shown to be an estrogen-induced chromatin regulator, plays a crucial role in the up- and downregulation of kinesins by estrogen. Its overexpression drives estrogen-independent upregulation of specific kinesins. Mechanistically, ANCCA (AAA nuclear coregulator cancer associated) mediates E2-dependent recruitment of E2F and MLL1 histone methyltransferase at kinesin gene promoters for gene activation–associated H3K4me3 methylation. Importantly, elevated levels of Kif4A, Kif15, Kif20A, and Kif23 correlate with that of ANCCA in the tumors and with poor relapse-free survival of patients with ER-positive breast cancer. Their knockdown strongly impeded proliferation and induced apoptosis of both tamoxifen-sensitive and resistant cancer cells. Together, the study reveals ANCCA as a key mediator of kinesin family deregulation in breast cancer and the crucial role of multiple kinesins in growth and survival of the tumor cells.

Implications: These findings support the development of novel inhibitors of cancer-associated kinesins and their regulator ANCCA for effective treatment of cancers including tamoxifen-resistant breast cancers. Mol Cancer Res; 12(4); 539–49. ©2014 AACR.
Data from Functional Heterogeneity of PAX5 Chimeras Reveals Insight for Leukemia Development
Authors: Fortschegger Klaus , Anderl Stefanie , Denk Dagmar , Strehl Sabine
Published: April 2023

Abstract
PAX5, a transcription factor pivotal for B-cell commitment and maintenance, is one of the most frequent targets of somatic mutations in B-cell precursor acute lymphoblastic leukemia. A number of PAX5 rearrangements result in the expression of in-frame fusion genes encoding chimeric proteins, which at the N-terminus consistently retain the PAX5 DNA-binding paired domain fused to the C-terminal domains of a markedly heterogeneous group of fusion partners. PAX5 fusion proteins are thought to function as aberrant transcription factors, which antagonize wild-type PAX5 activity. To gain mechanistic insight into the role of PAX5 fusion proteins in leukemogenesis, the biochemical and functional properties of uncharacterized fusions: PAX5–DACH1, PAX5–DACH2, PAX5–ETV6, PAX5–HIPK1, and PAX5–POM121 were ascertained. Independent of the subcellular distribution of the wild-type partner proteins, ectopic expression of all PAX5 fusion proteins showed a predominant nuclear localization, and by chromatin immunoprecipitation all of the chimeric proteins exhibited binding to endogenous PAX5 target sequences. Furthermore, consistent with the presence of potential oligomerization motifs provided by the partner proteins, the self-interaction capability of several fusion proteins was confirmed. Remarkably, a subset of the PAX5 fusion proteins conferred CD79A promoter activity; however, in contrast with wild-type PAX5, the fusion proteins were unable to induce Cd79a transcription in a murine plasmacytoma cell line. These data show that leukemia-associated PAX5 fusion proteins share some dominating characteristics such as nuclear localization and DNA binding but also show distinctive features.

Implications: This comparative study of multiple PAX5 fusion proteins demonstrates both common and unique properties, which likely dictate their function and impact on leukemia development. Mol Cancer Res; 12(4); 595–606. ©2014 AACR.
Data from Unbiased Proteomic and Transcript Analyses Reveal that Stathmin-1 Silencing Inhibits Colorectal Cancer Metastasis and Sensitizes to 5-Fluorouracil Treatment
Authors: Wu Wei , Tan Xing Fei , Tan Hwee Tong , Lim Teck Kwang , Chung Maxey Ching Ming
Published: April 2023

Abstract
Colorectal cancer metastasis is a major cause of mortality worldwide, which may only be controlled with novel methods limiting tumor dissemination and chemoresistance. High stathmin-1 (STMN1) expression was previously established as a hallmark of colorectal cancer progression and predictor of poor survival; however, the mechanism of action is less clear. This work demonstrates that STMN1 silencing arrests tumor-disseminative cascades by inhibiting multiple metastatic drivers, and repressing oncogenic and mesenchymal transcription. Using a sensitive iTRAQ labeling proteomic approach that quantified differential abundance of 4562 proteins, targeting STMN1 expression was shown to reinstate the default cellular program of metastatic inhibition, and promote cellular adhesion via amplification of hemidesmosomal junctions and intermediate filament tethering. Silencing STMN1 also significantly improved chemoresponse to the classical colorectal cancer therapeutic agent, 5FU, via a novel caspase-6 (CASP6)–dependent mechanism. Interestingly, the prometastatic function of STMN1 was independent of p53 but required phosphorylations at S25 or S38; abrogating phosphorylative events may constitute an alternative route to achieving metastatic inhibition. These findings establish STMN1 as a potential target in antimetastatic therapy, and demonstrate the power of an approach coupling proteomics and transcript analyses in the global assessment of treatment benefits and potential side-effects.

Implications: Stathmin-1 is a potential candidate in colorectal cancer therapy that targets simultaneously the twin problems of metastatic spread and chemoresistance. Mol Cancer Res; 12(12); 1717–28. ©2014 AACR.
Data from Increased Expression of Beige/Brown Adipose Markers from Host and Breast Cancer Cells Influence Xenograft Formation in Mice
Authors: Singh Rajan , Parveen Meher , Basgen John M. , Fazel Sayeda , Meshesha Meron F. , Thames Easter C. , Moore Brandis , Martinez Luis , Howard Carolyn B. , Vergnes Laurent , Reue Karen , Pervin Shehla
Published: April 2023

Abstract
The initiation and progression of breast cancer is a complex process that is influenced by heterogeneous cell populations within the tumor microenvironment. Although adipocytes have been shown to promote breast cancer development, adipocyte characteristics involved in this process remain poorly understood. In this study, we demonstrate enrichment of beige/brown adipose markers, contributed from the host as well as tumor cells, in the xenografts from breast cancer cell lines. In addition to uncoupling protein-1 (UCP1) that is exclusively expressed in beige/brown adipocytes, gene expression for classical brown (MYF5, EVA1, and OPLAH) as well as beige (CD137/TNFRSF9 and TBX1) adipocyte markers was also elevated in the xenografts. Enrichment of beige/brown characteristics in the xenografts was independent of the site of implantation of the breast tumor cells. Early stages of xenografts showed an expansion of a subset of mammary cancer stem cells that expressed PRDM16, a master regulator of brown adipocyte differentiation. Depletion of UCP1+ or Myf5+ cells significantly reduced tumor development. There was increased COX2 (MT-CO2) expression, which is known to stimulate formation of beige adipocytes in early xenografts and treatment with a COX2 inhibitor (SC236) reduced tumor growth. In contrast, treatment with factors that induce brown adipocyte differentiation in vitro led to larger tumors in vivo. A panel of xenografts derived from established breast tumor cells as well as patient tumor tissues were generated that expressed key brown adipose tissue–related markers and contained cells that morphologically resembled brown adipocytes.

Implications: This is the first report demonstrating that beige/brown adipocyte characteristics could play an important role in breast tumor development and suggest a potential target for therapeutic drug design. Mol Cancer Res; 14(1); 78–92. ©2015 AACR.
Data from FGFR3 Translocations in Bladder Cancer: Differential Sensitivity to HSP90 Inhibition Based on Drug Metabolism
Authors: Acquaviva Jaime , He Suqin , Zhang Chaohua , Jimenez John-Paul , Nagai Masazumi , Sang Jim , Sequeira Manuel , Smith Donald L. , Ogawa Luisa Shin , Inoue Takayo , Tatsuta Noriaki , Knowles Margaret A. , Bates Richard C. , Proia David A.
Published: April 2023

Abstract
Activating mutations and/or overexpression of FGFR3 are common in bladder cancer, making FGFR3 an attractive therapeutic target in this disease. In addition, FGFR3 gene rearrangements have recently been described that define a unique subset of bladder tumors. Here, a selective HSP90 inhibitor, ganetespib, induced loss of FGFR3-TACC3 fusion protein expression and depletion of multiple oncogenic signaling proteins in RT112 bladder cells, resulting in potent cytotoxicity comparable with the pan-FGFR tyrosine kinase inhibitor BGJ398. However, in contrast to BGJ398, ganetespib exerted pleiotropic effects on additional mitogenic and survival pathways and could overcome the FGFR inhibitor–resistant phenotype of FGFR3 mutant–expressing 97-7 and MHG-U3 cells. Combinatorial benefit was observed when ganetespib was used with BGJ398 both in vitro and in vivo. Interestingly, two additional FGFR3 fusion-positive lines (RT4 and SW480) retained sensitivity to HSP90 inhibitor treatment by the ansamycins 17-AAG and 17-DMAG yet displayed intrinsic resistance to ganetespib or AUY922, both second-generation resorcinol-based compounds. Both cell lines, compared with RT112, expressed considerably higher levels of endogenous UGT1A enzyme; this phenotype resulted in a rapid glucuronidation-dependent metabolism and subsequent efflux of ganetespib from SW780 cells, thus providing a mechanism to account for the lack of bioactivity.

Implications: Pharmacologic blockade of the molecular chaperone HSP90 represents a promising approach for treating bladder tumors driven by oncogenic gene rearrangements of FGFR3. Furthermore, UDP-glucuronosyltransferase enzyme expression may serve as a predictive factor for clinical response to resorcinol-based HSP90 inhibitors. Mol Cancer Res; 12(7); 1042–54. ©2014 AACR.
Data from Transcriptional Regulation of miR-31 by Oncogenic KRAS Mediates Metastatic Phenotypes by Repressing RASA1
Authors: Kent Oliver A. , Mendell Joshua T. , Rottapel Robert
Published: April 2023

Abstract
Activating KRAS mutations are nearly ubiquitous in pancreatic cancer occurring in more than 95% of clinical cases. miRNAs are small noncoding RNAs that regulate gene expression by binding sequences within the 3′UTRs of target mRNAs. An integral role for miRNAs in cancer pathogenesis is well established; however, the role of miRNAs in KRAS-mediated tumorigenesis is poorly characterized. Here it is demonstrated that expression of miR-31 is coupled to the expression of oncogenic KRAS and activity of the MAPK pathway. miR-31 is highly expressed in patient-derived xenografts and a panel of pancreatic and colorectal cancer cells harboring activating KRAS mutations. The miR-31 host gene is a large noncoding RNA that correlates with miR-31 expression and enabled identification of the putative miR-31 promoter. Using luciferase reporters, a minimal RAS-responsive miR-31 promoter was found to drive robust luciferase activity dependent on expression of mutant KRAS and the transcription factor ELK1. Furthermore, ELK1 interacts directly with the endogenous miR-31 promoter in a MAPK-dependent manner. Expression of enforced miR-31 significantly enhanced invasion and migration of multiple pancreatic cancer cells resulting from the activation of RhoA through regulation of the miR-31 target gene RASA1. Importantly, acute knockdown of RASA1 phenocopied enforced miR-31 expression on the migratory behavior of pancreatic cancer cells through increased RhoA activation.

Implications: Oncogenic KRAS can activate Rho through the miR-31–mediated regulation of RASA1 indicating miR-31 acts as a KRAS effector to modulate invasion and migration in pancreatic cancer. Mol Cancer Res; 14(3); 267–77. ©2016 AACR.
Data from CHCHD2 Is Coamplified with EGFR in NSCLC and Regulates Mitochondrial Function and Cell Migration
Authors: Wei Yuhong , Vellanki Ravi N. , Coyaud Étienne , Ignatchenko Vladimir , Li Lei , Krieger Jonathan R. , Taylor Paul , Tong Jiefei , Pham Nhu-An , Liu Geoffrey , Raught Brian , Wouters Bradly G. , Kislinger Thomas , Tsao Ming Sound , Moran Michael F.
Published: April 2023

Abstract
Coiled-coil-helix-coiled-coil-helix domain-containing 2, a mitochondrial protein, encoded by CHCHD2 is located at chromosome 7p11.2 and proximal to the EGFR gene. Here, bioinformatic analyses revealed that CHCHD2 is consistently coamplified with EGFR in non–small cell lung carcinoma (NSCLC). In addition, CHCHD2 and EGFR protein expression levels were positively correlated and upregulated relative to normal lung in NSCLC tumor-derived xenografts. Knockdown of CHCHD2 expression in NSCLC cells attenuated cell proliferation, migration, and mitochondrial respiration. CHCHD2 protein–protein interactions were assessed by the complementary approaches of affinity purification mass spectrometry and in vivo proximity ligation. The CHCHD2 interactome includes the apparent hub proteins C1QBP (a mitochondrial protein) and YBX1 (an oncogenic transcription factor), and an overlapping set of hub-associated proteins implicated in cell regulation.

Implications: CHCHD2 influences mitochondrial and nuclear functions and contributes to the cancer phenotype associated with 7p11.2 amplification in NSCLC. Mol Cancer Res; 13(7); 1119–29. ©2015 AACR.
Data from Optical Imaging of Glucose Uptake and Mitochondrial Membrane Potential to Characterize Her2 Breast Tumor Metabolic Phenotypes
Authors: Madonna Megan C. , Fox Douglas B. , Crouch Brian T. , Lee Jihong , Zhu Caigang , Martinez Amy F. , Alvarez James V. , Ramanujam Nirmala
Published: April 2023

Abstract
With the large number of women diagnosed and treated for breast cancer each year, the importance of studying recurrence has become evident due to most deaths from breast cancer resulting from tumor recurrence following therapy. To mitigate this, cellular and molecular pathways used by residual disease prior to recurrence must be studied. An altered metabolism has long been considered a hallmark of cancer, and several recent studies have gone further to report metabolic dysfunction and alterations as key to understanding the underlying behavior of dormant and recurrent cancer cells. Our group has used two probes, 2-[N-(7-nitrobenz-2-oxa-1, 3-diaxol-4-yl) amino]-2-deoxyglucose (2-NBDG) and tetramethyl rhodamine ethyl ester (TMRE), to image glucose uptake and mitochondrial membrane potential, respectively, to report changes in metabolism between primary tumors, regression, residual disease, and after regrowth in genetically engineered mouse (GEM)-derived mammospheres. Imaging revealed unique metabolic phenotypes across the stages of tumor development. Although primary mammospheres overexpressing Her2 maintained increased glucose uptake (“Warburg effect”), after Her2 downregulation, during regression and residual disease, mammospheres appeared to switch to oxidative phosphorylation. Interestingly, in mammospheres where Her2 overexpression was turned back on to model recurrence, glucose uptake was lowest, indicating a potential change in substrate preference following the reactivation of Her2, reeliciting growth. Our findings highlight the importance of imaging metabolic adaptions to gain insight into the fundamental behaviors of residual and recurrent disease.
Implications:
This study demonstrates these functional fluorescent probes' ability to report metabolic adaptations during primary tumor growth, regression, residual disease, and regrowth in Her2 breast tumors.
Data from Tumor Progression Is Mediated by Thymosin-β4 through a TGFβ/MRTF Signaling Axis
Authors: Morita Tsuyoshi , Hayashi Ken'ichiro
Published: April 2023

Abstract
Although enhanced thymosin β4 (TMSB4X/Tβ4) expression is associated with tumor progression and metastasis, its tumor-promoting functions remain largely unknown. Here, it is demonstrated that TGFβ facilitates Tβ4 expression and leads to the activation of myocardin-related transcription factors (MRTF), which are coactivators of serum response factor (SRF) and regulate the expression of genes critical for the epithelial–mesenchymal transition (EMT) and tumor metastasis. In murine mammary gland cells (NMuMG), Tβ4 upregulation is required for full induction of a MRTF-regulated EMT gene expression program after TGFβ stimulation. Tβ4 levels are transcriptionally regulated via the novel cis-acting element AGACAAAG, which interacts with Smad and T-cell factor/lymphoid enhancer factor (TCF/LEF) to synergistically activate the Tβ4 promoter downstream of TGFβ. Murine skin melanoma cells (B16F0 and B16F1) also show the expression regulation of Tβ4 by Smad and TCF/LEF. Tβ4-knockout B16F1 (Tβ4 KO) clones show significantly diminished expression level of tumor-associated genes, which is regulated by the TGFβ/MRTFs pathway. In multiple human cancers, Tβ4 levels correlate positively with TGFβ1 and the tumor-associated gene expression levels through processes that respectively depend on TGFβ receptor 1 (TGFBR1) and MRTF expression. Kaplan–Meier survival analyses demonstrate that high Tβ4 expression associates with poor prognosis in an SRF expression–dependent manner in several cancers. In mice, Tβ4 KO clones show significantly decreased experimental metastatic potential; furthermore, ectopic expression of constitutively active MRTF-A fully restores the diminished metastatic activity. In conclusion, the TGFβ/Tβ4/MRTF/SRF pathway is critical for metastasis and tumor progression.

Implications: These findings define a molecular mechanism underlying a tumor-promoting function of thymosin β4 through activation of MRTF/SRF signaling. Mol Cancer Res; 16(5); 880–93. ©2018 AACR.
Data from Integrated Genomic Comparison of Mouse Models Reveals Their Clinical Resemblance to Human Liver Cancer
Authors: Yim Sun Young , Shim Jae-Jun , Shin Ji-Hyun , Jeong Yun Seong , Kang Sang-Hee , Kim Sang-Bae , Eun Young Gyu , Lee Dong Jin , Conner Elizabeth A. , Factor Valentina M. , Moore David D. , Johnson Randy L. , Thorgeirsson Snorri S. , Lee Ju-Seog
Published: April 2023

Abstract
Hepatocellular carcinoma (HCC) is a heterogeneous disease. Mouse models are commonly used as preclinical models to study hepatocarcinogenesis, but how well these models recapitulate molecular subtypes of human HCC is unclear. Here, integration of genomic signatures from molecularly and clinically defined human HCC (n = 11) and mouse models of HCC (n = 9) identified the mouse models that best resembled subtypes of human HCC and determined the clinical relevance of each model. Mst1/2 knockout (KO), Sav1 KO, and SV40 T antigen mouse models effectively recapitulated subtypes of human HCC with a poor prognosis, whereas the Myc transgenic model best resembled human HCCs with a more favorable prognosis. The Myc model was also associated with activation of β-catenin. E2f1, E2f1/Myc, E2f1/Tgfa, and diethylnitrosamine (DEN)-induced models were heterogeneous and were unequally split into poor and favorable prognoses. Mst1/2 KO and Sav1 KO models best resemble human HCC with hepatic stem cell characteristics. Applying a genomic predictor for immunotherapy, the six-gene IFNγ score, the Mst1/2 KO, Sav1 KO, SV40, and DEN models were predicted to be the least responsive to immunotherapy. Further analysis showed that elevated expression of immune-inhibitory genes (Cd276 and Nectin2/Pvrl2) in Mst1/2 KO, Sav1 KO, and SV40 models and decreased expression of immune stimulatory gene (Cd86) in the DEN model might be accountable for the lack of predictive response to immunotherapy.

Implication: The current genomic approach identified the most relevant mouse models to human liver cancer and suggests immunotherapeutic potential for the treatment of specific subtypes. Mol Cancer Res; 16(11); 1713–23. ©2018 AACR.
Data from Proinflammatory Macrophages Promote Multiple Myeloma Resistance to Bortezomib Therapy
Authors: Beyar-Katz Ofrat , Magidey Ksenia , Reiner-Benaim Anat , Barak Noga , Avivi Irit , Cohen Yael , Timaner Michael , Avraham Shimrit , Hayun Michal , Lavi Noa , Bersudsky Marina , Voronov Elena , Apte Ron N. , Shaked Yuval
Published: April 2023

Abstract
Multiple myeloma (MM) is a plasma cell neoplasia commonly treated with proteasome inhibitors such as bortezomib. Although bortezomib has demonstrated enhanced survival benefit, some patients relapse and subsequently develop resistance to such therapy. Here, we investigate the mechanisms underlying relapse and refractory MM following bortezomib treatment. We show that bortezomib-exposed proinflammatory macrophages promote an enrichment of MM-tumor-initiating cells (MM-TIC) both in vitro and in vivo. These effects are regulated in part by IL1β, as blocking the IL1β axis by a pharmacologic or genetic approach abolishes bortezomib-induced MM-TIC enrichment. In MM patients treated with bortezomib, high proinflammatory macrophages in the bone marrow negatively correlate with survival rates (HR, 1.722; 95% CI, 1.138–2.608). Furthermore, a positive correlation between proinflammatory macrophages and TICs in the bone marrow was also found. Overall, our results uncover a protumorigenic cross-talk involving proinflammatory macrophages and MM cells in response to bortezomib therapy, a process that enriches the MM-TIC population.
Implications:
Our findings suggest that proinflammatory macrophages in bone marrow biopsies represent a potential prognostic biomarker for acquired MM resistance to bortezomib therapy.
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: April 2023

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 Serum CD95L Level Correlates with Tumor Immune Infiltration and Is a Positive Prognostic Marker for Advanced High-Grade Serous Ovarian Cancer
Authors: De La Motte Rouge Thibault , Corné Julien , Cauchois Aurélie , Le Boulch Marie , Poupon Clotilde , Henno Sébastien , Rioux-Leclercq Nathalie , Le Pabic Estelle , Laviolle Bruno , Catros Véronique , Levêque Jean , Fautrel Alain , Le Gallo Matthieu , Legembre Patrick , Lavoué Vincent
Published: April 2023

Abstract
Soluble CD95L (s-CD95L) is a chemoattractant for certain lymphocyte subpopulations. We examined whether this ligand is a prognostic marker for high-grade serous ovarian cancer (HGSOC) and whether it is associated with accumulation of immune cells in the tumor. Serum s-CD95L levels in 51 patients with advanced ovarian cancer were tested by ELISA. IHC staining of CD3, CD4, CD8, CD20, CD163, CD31, FoxP3, CCR6, IL-17, Granzyme B, PD-L1, and membrane CD95L was used to assess tumor-infiltrating immune cells. Although the intensity of CD3, CD8, CD4, CD20, and CD163 in tumor tissues remained constant regardless of membrane CD95L expression, tumors in patients with HGSOC with s-CD95L levels ≥516 pg/mL showed increased infiltration by CD3+ T cells (P = 0.001), comprising both cytotoxic CD8+ (P = 0.01) and CD4+ (P = 0.0062) cells including FoxP3+ regulatory T cells (P = 0.0044). Also, the number of tumor-infiltrating CD20+ B cells (P = 0.0094) increased in these patients. Multivariate analyses revealed that low s-CD95L concentrations [<516 pg/mL, HR, 3.54; 95% confidence interval (CI), 1.13–11.11), and <1,200 activated CD8+ (Granzyme B+) cells (HR, 2.63; 95% CI, 1.16–5.95) were independent poor prognostic factors for recurrence, whereas >6,000 CD3+ cells (HR, 0.34; 95% CI, 0.15–0.79) was a good prognostic factor. Thus, low levels of s-CD95L (<516 pg/mL) are correlated with lower numbers of tumor-infiltrating lymphocytes (CD3+ and CD8+, and also CD4 and FoxP3 T cells) in advanced HGSOC and are a poor prognostic marker.
Implications:
Serum s-CD95L is correlated with a number of tumor-infiltrating immune cells in HGSOC and could be used as a noninvasive marker of tumor immune infiltration to select patients referred for immunotherapy trials that evaluate checkpoint inhibitor treatment.
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: April 2023

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.