bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Loss of SWI/SNF Chromatin Remodeling Alters NRF2 Signaling in Non–Small Cell Lung Carcinoma
Authors: Song Shujie , Nguyen Vinh , Schrank Travis , Mulvaney Kathleen , Walter Vonn , Wei Darmood , Orvis Tess , Desai Nisarg , Zhang Jiren , Hayes D. Neil , Zheng Yanfang , Major Michael B. , Weissman Bernard E.
Published: March 2024

Abstract
The NF-E2–related factor 2 (referred to as NRF2) transcription factor binds antioxidant responsive elements within the promoters of cytoprotective genes to induce their expression. Next-generation sequencing studies in lung cancer have shown a significant number of activating mutations within the NRF2 signaling pathway. Mutations in components of the SWI/SNF chromatin-remodeling complex, a general regulator of transcription using either BRG1 or BRM as the catalytic subunit, also frequently occur in lung cancers. Importantly, low BRG1 expression levels in primary human NSCLC correlated with increased NRF2-target gene expression. Here, we show that loss of SWI/SNF complex function activated a subset of NRF2-mediated transcriptional targets. Using a series of isogenic NSCLC lines with reduced or depleted BRG1 and/or BRM expression, we observed significantly increased expression of the NRF2-target genes HMOX1 and GSTM4. In contrast, expression of the NRF2 target genes NQO1 and GCLM modestly increased following BRM reduction. Chromatin immunoprecipitation showed that BRG1 knockdown led to increased NRF2 binding at its respective ARE sites in the HMOX1 promoter but not in NQO1 and GCLM. Our data demonstrate that loss of BRG1 or BRM in lung cancer results in activation of the NRF2/KEAP1 pathway and HMOX1 expression. Therefore, we provide an additional molecular explanation for why patients harboring BRG1 or BRM mutations show poor prognoses. A better understanding of this mechanism may yield novel insights into the design of targeted treatment modalities.
Implications:
Our study identifies a novel mechanism for how mutations in the SMARCA4 gene may drive progression of human lung adenocarcinomas.
Data from SLAMF3-Mediated Signaling via ERK Pathway Activation Promotes Aggressive Phenotypic Behaviors in Multiple Myeloma
Authors: Ishibashi Mariko , Takahashi Risa , Tsubota Asako , Sasaki Makoto , Handa Hiroshi , Imai Yoichi , Tanaka Norina , Tsukune Yutaka , Tanosaki Sakae , Ito Shigeki , Asayama Toshio , Sunakawa Mika , Kaito Yuta , Kuribayashi-Hamada Yasuko , Onodera Asaka , Moriya Keiichi , Komatsu Norio , Tanaka Junji , Odajima Takeshi , Sugimori Hiroki , Inokuchi Koiti , Tamura Hideto
Published: March 2024

Abstract
The signaling lymphocytic activation molecule family 3 (SLAMF3) is a member of the immunoglobulin superfamily expressed on T, B, and natural killer cells and modulates the activation and cytotoxicity of these cells. SLAMF3 is also expressed on plasma cells from patients with multiple myeloma (MM), although its role in MM pathogenesis remains unclear. This study found that SLAMF3 is highly and constitutively expressed on MM cells regardless of disease stage and that SLAMF3 knockdown/knockout suppresses proliferative potential and increases drug-induced apoptosis with decreased levels of phosphorylated ERK protein in MM cells. SLAMF3-overexpressing MM cells promote aggressive myeloma behavior in comparison with cytoplasmic domain-truncated SLAMF3 (ΔSLAMF3) cells. SLAMF3 interacts directly with adaptor proteins SH2 domain-containing phosphatase 2 (SHP2) and growth factor receptor bound 2 (GRB2), which also interact with each other. SLAMF3 knockdown, knockout, ΔSLAMF3, and SHP2 inhibitor-treated MM cells decreased phosphorylated ERK protein levels. Finally, serum soluble SLAMF3 (sSLAMF3) levels were markedly increased in advanced MM. Patients with high levels of sSLAMF3 progressed to the advanced stage significantly more often and had shorter progression-free survival times than those with low levels. This study revealed that SLAMF3 molecules consistently expressed on MM cells transmit MAPK/ERK signals mediated via the complex of SHP2 and GRB2 by self-ligand interaction between MM cells and induce a high malignant potential in MM. Furthermore, high levels of serum sSLAMF3 may reflect MM disease progression and be a useful prognostic factor.
Implications:
SLAMF3 may be a new therapeutic target for immunotherapy and novel agents such as small-molecule inhibitors.
Data from Colorectal Carcinogenesis: Connecting K-RAS–Induced Transformation and CREB Activity In Vitro and In Vivo
Authors: Steven André , Heiduk Max , Recktenwald Christian V. , Hiebl Bernhard , Wickenhauser Claudia , Massa Chiara , Seliger Barbara
Published: March 2024

Abstract
Oncogenic transformation is often associated with an increased expression of the cAMP response element binding (CREB) transcription factor controlling the expression of genes involved in cell proliferation, cell cycle, apoptosis, and tumor development, but a link between K-RASV12-induced transformation and CREB has not yet been determined. Therefore, the constitutive and/or inhibitor-regulated mRNA and protein expression of CREB and signal transduction components and growth properties of parental fibroblasts, K-RASV12-transformed counterparts, shCREB K-RASV12 transfectants and human colon carcinoma cells were determined. Increased CREB transcript and protein levels accompanied by an enhanced CREB activity was detected in K-RASV12-transformed murine fibroblasts and K-RASV12-mutated human tumor cells, which is dependent on the MAPK/MEK, PI3K, and/or PKC signal transduction. Immunohistochemical (IHC) staining of colorectal carcinoma lesions and murine tumors, with known KRAS gene mutation status, using antibodies specific for CREB and phospho-CREB, revealed a mechanistic link between CREB expression and K-RASV12-mutated colorectal carcinoma lesions when compared with control tissues. Silencing of CREB by shRNA and/or treatment with a CREB inhibitor (KG-501) reverted the neoplastic phenotype of K-RASV12 transformants as demonstrated by a more fibroblast-like morphology, enhanced apoptosis sensitivity, increased doubling time, decreased migration, invasion and anchorage-independent growth, reduced tumorigenesis, and enhanced immunogenicity in vivo. The impaired shCREB-mediated invasion of K-RASV12 transformants was accompanied by a transcriptional downregulation of different matrix metalloproteinases (MMP) coupled with their reduced enzymatic activity.

Implications: CREB plays a key role in the K-RASV12-mediated neoplastic phenotype and represents a suitable therapeutic target for murine and human K-RASV12-induced tumors. Mol Cancer Res; 13(8); 1248–62. ©2015 AACR.
Data from Genome-Wide Profiling of TRACK Kidneys Shows Similarity to the Human ccRCC Transcriptome
Authors: Fu Leiping , Minton Denise R. , Zhang Tuo , Nanus David M. , Gudas Lorraine J.
Published: March 2024

Abstract
Renal cell carcinoma (RCC) is the most common cancer arising from the kidney in adults, with clear cell RCC (ccRCC) representing the majority of all RCCs. Expression of a human HIF1α triple-mutant (P402A, P564A, and N803A) construct in the proximal tubule cells of C57BL/6 mice [TRAnsgenic model of Cancer of the Kidney (TRACK); ref. 1] mimics the histologic changes found in early stage human ccRCC. To better understand the genomic landscape, a high-throughput sequence analysis was performed with cDNA libraries (RNAseq) derived from TRACK transgenic positive (TG+) kidney cortex along with human ccRCC transcripts from the Oncomine and The Cancer Genome Atlas databases. Importantly, the expression profiles of TRACK TG+ kidneys show significant similarities with those observed in human ccRCC, including increased expression of genes involved in glycolysis and the tricarboxylic acid cycle. Some of the transcripts overexpressed in both the TRACK mouse model and human ccRCC include ANKRD37, CA9, EGLN3, HK2, NDUFA4L2, and SLC16A3. These data suggest that constitutive activation of HIF1α in kidney proximal tubule cells transcriptionally reprograms the regulation of metabolic pathways in the kidney and that HIF1α is a major contributor to the altered metabolism observed in human ccRCC.

Implications: TRACK (GGT-HIF1αM3) kidney mRNA profiles show similarities to human ccRCC transcriptome and phenotypes associated with the Warburg effect. Mol Cancer Res; 13(5); 870–8. ©2015 AACR.
Data from Detection of Tumor Suppressor Genes in Cancer Development by a Novel shRNA-Based Method
Authors: von Burstin Johannes , Diersch Sandra , Schneider Günter , Reichert Maximilian , Rustgi Anil K. , Schmid Roland M.
Published: March 2024

Abstract
Pancreatic cancer is one of the deadliest cancers with poor survival rates and limited therapeutic options. To improve the understanding of this disease's biology, a prerequisite for the generation of novel therapeutics, new platforms for rapid and efficient genetic and therapeutic screening are needed. Therefore, a combined in vitro/in vivo hybrid shRNA assay was developed using isolated murine primary pancreatic ductal cells (PDCs), in which oncogenic KrasG12D could be activated in vitro by genomic recombination through 4OH-tamoxifen–induced nuclear translocation of Cre-ERT2 expressed under control of the ROSA26 promoter. Further genetic manipulation was achieved through selective and stable RNAi against the tumor suppressors p16Ink4a (CDKN2A) or Trp53 (TP53) using lentiviral gene delivery. Treatment of PDCs with 4OH-tamoxifen increased phosphorylation of ERK downstream of KRAS, and subsequent lentiviral transduction resulted in sustained target gene repression. Double-mutant PDCs were then reintroduced into the pancreata of NOD-SCID-gamma (NSG) mice and monitored for tumor growth. Orthotopic implantation of PDCs carrying the activated KrasG12D-allele and shRNA against p16Ink4a or Trp53 resulted in tumor growth, metastasis, and reduced survival of NSG mice. In contrast, KrasG12D alone was not sufficient to induce tumor growth.

Implications: The combinatory in vitro/in vivo approach described in this study allows for rapid and efficient identification of genes involved in carcinogenesis and opens new avenues for the development of therapeutic strategies to improve cancer treatment. Mol Cancer Res; 13(5); 863–9. ©2015 AACR.
Data from Nonamplified FGFR1 Is a Growth Driver in Malignant Pleural Mesothelioma
Authors: Marek Lindsay A. , Hinz Trista K. , von Mässenhausen Anne , Olszewski Kyle A. , Kleczko Emily K. , Boehm Diana , Weiser-Evans Mary C. , Nemenoff Raphael A. , Hoffmann Hans , Warth Arne , Gozgit Joseph M. , Perner Sven , Heasley Lynn E.
Published: March 2024

Abstract
Malignant pleural mesothelioma (MPM) is associated with asbestos exposure and is a cancer that has not been significantly affected by small molecule-based targeted therapeutics. Previously, we demonstrated the existence of functional subsets of lung cancer and head and neck squamous cell carcinoma (HNSCC) cell lines in which fibroblast growth factor receptor (FGFR) autocrine signaling functions as a nonmutated growth pathway. In a panel of pleural mesothelioma cell lines, FGFR1 and FGF2 were coexpressed in three of seven cell lines and were significantly associated with sensitivity to the FGFR-active tyrosine kinase inhibitor (TKI), ponatinib, both in vitro and in vivo using orthotopically propagated xenografts. Furthermore, RNAi-mediated silencing confirmed the requirement for FGFR1 in specific mesothelioma cells and sensitivity to the FGF ligand trap, FP-1039, validated the requirement for autocrine FGFs. None of the FGFR1-dependent mesothelioma cells exhibited increased FGFR1 gene copy number, based on a FISH assay, indicating that increased FGFR1 transcript and protein expression were not mediated by gene amplification. Elevated FGFR1 mRNA was detected in a subset of primary MPM clinical specimens and like MPM cells; none harbored increased FGFR1 gene copy number. These results indicate that autocrine signaling through FGFR1 represents a targetable therapeutic pathway in MPM and that biomarkers distinct from increased FGFR1 gene copy number such as FGFR1 mRNA would be required to identify patients with MPM bearing tumors driven by FGFR1 activity.

Implications: FGFR1 is a viable therapeutic target in a subset of MPMs, but FGFR TKI-responsive tumors will need to be selected by a biomarker distinct from increased FGFR1 gene copy number, possibly FGFR1 mRNA or protein levels. Mol Cancer Res; 12(10); 1460–9. ©2014 AACR.
Data from Treatment Efficacy and Resistance Mechanisms Using the Second-Generation ALK Inhibitor AP26113 in Human NPM-ALK–Positive Anaplastic Large Cell Lymphoma
Authors: Ceccon M. , Mologni L. , Giudici G. , Piazza R. , Pirola A. , Fontana D. , Gambacorti-Passerini C.
Published: March 2024

Abstract
ALK is a tyrosine kinase receptor involved in a broad range of solid and hematologic tumors. Among 70% to 80% of ALK+ anaplastic large cell lymphomas (ALCL) are caused by the aberrant oncogenic fusion protein NPM-ALK. Crizotinib was the first clinically relevant ALK inhibitor, now approved for the treatment of late-stage and metastatic cases of lung cancer. However, patients frequently develop drug resistance to Crizotinib, mainly due to the appearance of point mutations located in the ALK kinase domain. Fortunately, other inhibitors are available and in clinical trial, suggesting the potential for second-line therapies to overcome Crizotinib resistance. This study focuses on the ongoing phase I/II trial small-molecule tyrosine kinase inhibitor (TKI) AP26113, by Ariad Pharmaceuticals, which targets both ALK and EGFR. Two NPM-ALK+ human cell lines, KARPAS-299 and SUP-M2, were grown in the presence of increasing concentrations of AP26113, and eight lines were selected that demonstrated resistance. All lines show IC50 values higher (130 to 1,000-fold) than the parental line. Mechanistically, KARPAS-299 populations resistant to AP26113 show NPM-ALK overexpression, whereas SUP-M2–resistant cells harbor several point mutations spanning the entire ALK kinase domain. In particular, amino acid substitutions: L1196M, S1206C, the double F1174V+L1198F and L1122V+L1196M mutations were identified. The knowledge of the possible appearance of new clinically relevant mechanisms of drug resistance is a useful tool for the management of new TKI-resistant cases.

Implications: This work defines reliable ALCL model systems of AP26113 resistance and provides a valuable tool in the management of all cases of relapse upon NPM-ALK–targeted therapy. Mol Cancer Res; 13(4); 775–83. ©2014 AACR.
Data from Targeting TBK1 Inhibits Migration and Resistance to MEK Inhibitors in Mutant NRAS Melanoma
Authors: Vu Ha Linh , Aplin Andrew E.
Published: March 2024

Abstract
Melanoma is a devastating form of skin cancer with limited therapeutic options. Fifteen to 20% of patients with melanoma have an activating mutation in the GTPase, NRAS. The major downstream effectors of RAS are RAFs (ARAF, BRAF, and CRAF), phosphoinositide 3-kinase (PI3K), and the Ral guanine exchange factors (RalGEF). TANK-binding kinase 1 (TBK1) is an atypical IκB kinase family member that acts downstream of RalGEFs. Whereas many studies have analyzed RAF and PI3K signaling in mutant NRAS melanoma, the role of RalGEF/Ral is understudied and TBK1 has not been examined. To address this, TBK1 was modulated with knockdown approaches and targeted therapies to determine the role of TBK1 in motility, apoptosis, and signaling. In melanoma, NRAS overexpression increased TBK1 phosphorylation. TBK1 depletion inhibited migration and invasion, whereas its constitutive overexpression led to an increase in invasion. In three-dimensional systems that mimic the dermal microenvironment, TBK1 depletion or inhibition cooperated with MEK inhibitors to promote apoptosis, particularly in the context of MEK-insensitive mutant NRAS. This effect was absent in melanoma cells that are wild-type for NRAS. These results suggest the utility of TBK1 inhibitors as part of a treatment regimen for patients with mutant NRAS melanoma, for whom there are no current effective therapies.

Implications: TBK1 promotes the malignant properties of NRAS-mutant melanoma and its targeting, in combination with MEK, promotes apoptosis, thus providing a potential novel targeted therapeutic option. Mol Cancer Res; 12(10); 1509–19. ©2014 AACR.
Data from Estrogen Drives Cellular Transformation and Mutagenesis in Cells Expressing the Breast Cancer–Associated R438W DNA Polymerase Lambda Protein
Authors: Nemec Antonia A. , Bush Korie B. , Towle-Weicksel Jamie B. , Taylor B. Frazier , Schulz Vincent , Weidhaas Joanne B. , Tuck David P. , Sweasy Joann B.
Published: March 2024

Abstract
Repair of DNA damage is critical for maintaining the genomic integrity of cells. DNA polymerase lambda (POLL/Pol λ) is suggested to function in base excision repair (BER) and nonhomologous end-joining (NHEJ), and is likely to play a role in damage tolerance at the replication fork. Here, using next-generation sequencing, it was discovered that the POLL rs3730477 single-nucleotide polymorphism (SNP) encoding R438W Pol λ was significantly enriched in the germlines of breast cancer patients. Expression of R438W Pol λ in human breast epithelial cells induces cellular transformation and chromosomal aberrations. The role of estrogen was assessed as it is commonly used in hormone replacement therapies and is a known breast cancer risk factor. Interestingly, the combination of estrogen treatment and the expression of the R438W Pol λ SNP drastically accelerated the rate of transformation. Estrogen exposure produces 8-oxoguanine lesions that persist in cells expressing R438W Pol λ compared with wild-type (WT) Pol λ–expressing cells. Unlike WT Pol λ, which performs error-free bypass of 8-oxoguanine lesions, expression of R438W Pol λ leads to an increase in mutagenesis and replicative stress in cells treated with estrogen. Together, these data suggest that individuals who carry the rs3730477 POLL germline variant have an increased risk of estrogen-associated breast cancer.

Implications: The Pol λ R438W mutation can serve as a biomarker to predict cancer risk and implicates that treatment with estrogen in individuals with this mutation may further increase their risk of breast cancer. Mol Cancer Res; 14(11); 1068–77. ©2016 AACR.
Data from Cooperative Dynamics of AR and ER Activity in Breast Cancer
Authors: D'Amato Nicholas C. , Gordon Michael A. , Babbs Beatrice , Spoelstra Nicole S. , Carson Butterfield Kiel T. , Torkko Kathleen C. , Phan Vernon T. , Barton Valerie N. , Rogers Thomas J. , Sartorius Carol A. , Elias Anthony , Gertz Jason , Jacobsen Britta M. , Richer Jennifer K.
Published: March 2024

Abstract
Androgen receptor (AR) is expressed in 90% of estrogen receptor alpha–positive (ER+) breast tumors, but its role in tumor growth and progression remains controversial. Use of two anti-androgens that inhibit AR nuclear localization, enzalutamide and MJC13, revealed that AR is required for maximum ER genomic binding. Here, a novel global examination of AR chromatin binding found that estradiol induced AR binding at unique sites compared with dihydrotestosterone (DHT). Estradiol-induced AR-binding sites were enriched for estrogen response elements and had significant overlap with ER-binding sites. Furthermore, AR inhibition reduced baseline and estradiol-mediated proliferation in multiple ER+/AR+ breast cancer cell lines, and synergized with tamoxifen and fulvestrant. In vivo, enzalutamide significantly reduced viability of tamoxifen-resistant MCF7 xenograft tumors and an ER+/AR+ patient-derived model. Enzalutamide also reduced metastatic burden following cardiac injection. Finally, in a comparison of ER+/AR+ primary tumors versus patient-matched local recurrences or distant metastases, AR expression was often maintained even when ER was reduced or absent. These data provide preclinical evidence that anti-androgens that inhibit AR nuclear localization affect both AR and ER, and are effective in combination with current breast cancer therapies. In addition, single-agent efficacy may be possible in tumors resistant to traditional endocrine therapy, as clinical specimens of recurrent disease demonstrate AR expression in tumors with absent or refractory ER.

Implications: This study suggests that AR plays a previously unrecognized role in supporting E2-mediated ER activity in ER+/AR+ breast cancer cells, and that enzalutamide may be an effective therapeutic in ER+/AR+ breast cancers. Mol Cancer Res; 14(11); 1054–67. ©2016 AACR.
Data from Genomic Integration of High-Risk HPV Alters Gene Expression in Oropharyngeal Squamous Cell Carcinoma
Authors: Walline Heather M. , Komarck Christine M. , McHugh Jonathan B. , Bellile Emily L. , Brenner J. Chad , Prince Mark E. , McKean Erin L. , Chepeha Douglas B. , Wolf Gregory T. , Worden Francis P. , Bradford Carol R. , Carey Thomas E.
Published: March 2024

Abstract
High-risk HPV (hrHPV) is the leading etiologic factor in oropharyngeal cancer. HPV-positive oropharyngeal tumors generally respond well to therapy, with complete recovery in approximately 80% of patients. However, it remains unclear why some patients are nonresponsive to treatment, with 20% of patients recurring within 5 years. In this study, viral factors were examined for possible clues to differences in tumor behavior. Oropharynx tumors that responded well to therapy were compared with those that persisted and recurred. Viral oncogene alternate transcripts were assessed, and cellular sites of viral integration were mapped and sequenced. Effects of integration on gene expression were assessed by transcript analysis at the integration sites. All of the tumors demonstrated active viral oncogenesis, indicated by expression of HPV E6 and E7 oncogenes and alternate E6 splicing. In the responsive tumors, HPV integration occurred exclusively in intergenic chromosome regions, except for one tumor with viral integration into TP63. Each recurrent tumor exhibited complex HPV integration patterns into cancer-associated genes, including TNFRSF13B, SCN2A, SH2B1, UBE2V2, SMOC1, NFIA, and SEMA6D. Disrupted cellular transcripts were identified in the region of integration in four of the seven affected genes.

Implications: Integration of transcriptionally active hrHPV into cellular intergenic regions associates with tumor behavior by altering gene expression. Mol Cancer Res; 14(10); 941–52. ©2016 AACR.
Data from Inhibition of S-Adenosylmethionine-Dependent Methyltransferase Attenuates TGFβ1-Induced EMT and Metastasis in Pancreatic Cancer: Putative Roles of miR-663a and miR-4787-5p
Authors: Mody Hardik R. , Hung Sau Wai , AlSaggar Mohammad , Griffin Jazmine , Govindarajan Rajgopal
Published: March 2024

Abstract
The identification of epigenetic reversal agents for use in combination chemotherapies to treat human pancreatic ductal adenocarcinomas (PDAC) remains an unmet clinical need. Pharmacologic inhibitors of Enhancer of Zeste Homolog 2 (EZH2) are emerging as potential histone methylation reversal agents for the treatment of various solid tumors and leukemia; however, the surprisingly small set of mRNA targets identified with EZH2 knockdown suggests novel mechanisms contribute to their antitumorigenic effects. Here, 3-deazaneplanocin-A (DZNep), an inhibitor of S-adenosyl-L-homocysteine hydrolase and EZH2 histone lysine-N-methyltransferase, significantly reprograms noncoding microRNA (miRNA) expression and dampens TGFβ1-induced epithelial-to-mesenchymal (EMT) signals in pancreatic cancer. In particular, miR-663a and miR-4787-5p were identified as PDAC-downregulated miRNAs that were reactivated by DZNep to directly target TGFβ1 for RNA interference. Lentiviral overexpression of miR-663a and miR-4787-5p reduced TGFβ1 synthesis and secretion in PDAC cells and partially phenocopied DZNep's EMT-resisting effects, whereas locked nucleic acid (LNA) antagomiRNAs counteracted them. DZNep, miR-663a, and miR-4787-5p reduced tumor burden in vivo and metastases in an orthotopic mouse pancreatic tumor model. Taken together, these findings suggest the epigenetic reprogramming of miRNAs by synthetic histone methylation reversal agents as a viable approach to attenuate TGFβ1-induced EMT features in human PDAC and uncover putative miRNA targets involved in the process.

Implications: The findings support the potential for synthetic histone methylation reversal agents to be included in future epigenetic–chemotherapeutic combination therapies for pancreatic cancer. Mol Cancer Res; 14(11); 1124–35. ©2016 AACR.
Data from Calcipotriol Targets LRP6 to Inhibit Wnt Signaling in Pancreatic Cancer
Authors: Arensman Michael D. , Nguyen Phillip , Kershaw Kathleen M. , Lay Anna R. , Ostertag-Hill Claire A. , Sherman Mara H. , Downes Michael , Liddle Christopher , Evans Ronald M. , Dawson David W.
Published: March 2024

Abstract
Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy in need of more effective treatment approaches. One potential therapeutic target is Wnt/β-catenin signaling, which plays important roles in PDAC tumor initiation and progression. Among Wnt inhibitors with suitable in vivo biologic activity is vitamin D, which is known to antagonize Wnt/β-catenin signaling in colorectal cancer and have antitumor activity in PDAC. For this study, the relationship between vitamin D signaling, Wnt/β-catenin activity, and tumor cell growth in PDAC was investigated through the use of calcipotriol, a potent non-hypercalcemic vitamin D analogue. PDAC tumor cell growth inhibition by calcipotriol was positively correlated with vitamin D receptor expression and Wnt/β-catenin activity. Furthermore, vitamin D and Wnt signaling activity were found to be reciprocally linked through feedback regulation. Calcipotriol inhibited autocrine Wnt/β-catenin signaling in PDAC cell lines in parallel with decreased protein levels of the low-density lipoprotein receptor-related protein 6 (LRP6), a requisite coreceptor for ligand-dependent canonical Wnt signaling. Decrease in LRP6 protein seen with calcipotriol was mediated through a novel mechanism involving transcriptional upregulation of low-density lipoprotein receptor adaptor protein 1 (LDLRAP1). Finally, changes in LRP6 or LDLRAP1 expression directly altered Wnt reporter activity, supporting their roles as regulators of ligand-dependent Wnt/β-catenin signaling.

Implications: This study provides a novel biochemical target through which vitamin D signaling exerts inhibitory effects on Wnt/β-catenin signaling, as well as potential biomarkers for predicting and following tumor response to vitamin D–based therapy. Mol Cancer Res; 13(11); 1509–19. ©2015 AACR.
Data from AKT1E17K Activates Focal Adhesion Kinase and Promotes Melanoma Brain Metastasis
Authors: Kircher David A. , Trombetti Kirby A. , Silvis Mark R. , Parkman Gennie L. , Fischer Grant M. , Angel Stephanie N. , Stehn Christopher M. , Strain Sean C. , Grossmann Allie H. , Duffy Keith L. , Boucher Kenneth M. , McMahon Martin , Davies Michael A. , Mendoza Michelle C. , VanBrocklin Matthew W. , Holmen Sheri L.
Published: March 2024

Abstract
Alterations in the PI3K/AKT pathway occur in up to 70% of melanomas and are associated with disease progression. The three AKT paralogs are highly conserved but data suggest they have distinct functions. Activating mutations of AKT1 and AKT3 occur in human melanoma but their role in melanoma formation and metastasis remains unclear. Using an established melanoma mouse model, we evaluated E17K, E40K, and Q79K mutations in AKT1, AKT2, and AKT3 and show that mice harboring tumors expressing AKT1E17K had the highest incidence of brain metastasis and lowest mean survival. Tumors expressing AKT1E17K displayed elevated levels of focal adhesion factors and enhanced phosphorylation of focal adhesion kinase (FAK). AKT1E17K expression in melanoma cells increased invasion and this was reduced by pharmacologic inhibition of either AKT or FAK. These data suggest that the different AKT paralogs have distinct roles in melanoma brain metastasis and that AKT and FAK may be promising therapeutic targets.
Implications:
This study suggests that AKT1E17K promotes melanoma brain metastasis through activation of FAK and provides a rationale for the therapeutic targeting of AKT and/or FAK to reduce melanoma metastasis.
Data from Targeting Nodal in Conjunction with Dacarbazine Induces Synergistic Anticancer Effects in Metastatic Melanoma
Authors: Hardy Katharine M. , Strizzi Luigi , Margaryan Naira V. , Gupta Kanika , Murphy George F. , Scolyer Richard A. , Hendrix Mary J.C.
Published: March 2024

Abstract
Metastatic melanoma is a highly aggressive skin cancer with a poor prognosis. Despite a complete response in fewer than 5% of patients, the chemotherapeutic agent dacarbazine (DTIC) remains the reference drug after almost 40 years. More recently, FDA-approved drugs have shown promise but patient outcome remains modest, predominantly due to drug resistance. As such, combinatorial targeting has received increased attention, and will advance with the identification of new molecular targets. One attractive target for improving melanoma therapy is the growth factor Nodal, whose normal expression is largely restricted to embryonic development, but is reactivated in metastatic melanoma. In this study, we sought to determine how Nodal-positive human melanoma cells respond to DTIC treatment and to ascertain whether targeting Nodal in combination with DTIC would be more effective than monotherapy. A single treatment with DTIC inhibited cell growth but did not induce apoptosis. Rather than reducing Nodal expression, DTIC increased the size of the Nodal-positive subpopulation, an observation coincident with increased cellular invasion. Importantly, clinical tissue specimens from patients with melanomas refractory to DTIC therapy stained positive for Nodal expression, both in pre- and post-DTIC tumors, underscoring the value of targeting Nodal. In vitro, anti-Nodal antibodies alone had some adverse effects on proliferation and apoptosis, but combining DTIC treatment with anti-Nodal antibodies decreased cell growth and increased apoptosis synergistically, at concentrations incapable of producing meaningful effects as monotherapy.

Implications: Targeting Nodal in combination with DTIC therapy holds promise for the treatment of metastatic melanoma. Mol Cancer Res; 13(4); 670–80. ©2015 AACR.
Data from NR4A2 Promotes DNA Double-strand Break Repair Upon Exposure to UVR
Authors: Yin Kelvin , Chhabra Yash , Tropée Romain , Lim Yi Chieh , Fane Mitchell , Dray Eloise , Sturm Richard A. , Smith Aaron G.
Published: March 2024

Abstract
Exposure of melanocytes to ultraviolet radiation (UVR) induces the formation of UV lesions that can produce deleterious effects in genomic DNA. Encounters of replication forks with unrepaired UV lesions can lead to several complex phenomena, such as the formation of DNA double-strand breaks (DSBs). The NR4A family of nuclear receptors are transcription factors that have been associated with mediating DNA repair functions downstream of the MC1R signaling pathway in melanocytes. In particular, emerging evidence shows that upon DNA damage, the NR4A2 receptor can translocate to sites of UV lesion by mechanisms requiring post-translational modifications within the N-terminal domain and at a serine residue in the DNA-binding domain at position 337. Following this, NR4A2 aids in DNA repair by facilitating chromatin relaxation, allowing accessibility for DNA repair machinery. Using A2058 and HT144 melanoma cells engineered to stably express wild-type or mutant forms of the NR4A2 proteins, we reveal that the expression of functional NR4A2 is associated with elevated cytoprotection against UVR. Conversely, knockdown of NR4A2 expression by siRNA results in a significant loss of cell viability after UV insult. By analyzing the kinetics of the ensuing 53BP1 and RAD51 foci following UV irradiation, we also reveal that the expression of mutant NR4A2 isoforms, lacking the ability to translocate, transactivate, or undergo phosphorylation, display compromised repair capacity.

Implications: These data expand the understanding of the mechanism by which the NR4A2 nuclear receptor can facilitate DNA DSB repair. Mol Cancer Res; 15(9); 1184–96. ©2017 AACR.
Data from Dynamic Epigenetic Regulation by Menin During Pancreatic Islet Tumor Formation
Authors: Lin Wenchu , Watanabe Hideo , Peng Shouyong , Francis Joshua M. , Kaplan Nathan , Pedamallu Chandra Sekhar , Ramachandran Aruna , Agoston Agoston , Bass Adam J. , Meyerson Matthew
Published: March 2024

Abstract
The tumor suppressor gene MEN1 is frequently mutated in sporadic pancreatic neuroendocrine tumors (PanNET) and is responsible for the familial multiple endocrine neoplasia type 1 (MEN-1) cancer syndrome. Menin, the protein product of MEN1, associates with the histone methyltransferases (HMT) MLL1 (KMT2A) and MLL4 (KMT2B) to form menin–HMT complexes in both human and mouse model systems. To elucidate the role of methylation of histone H3 at lysine 4 (H3K4) mediated by menin–HMT complexes during PanNET formation, genome-wide histone H3 lysine 4 trimethylation (H3K4me3) signals were mapped in pancreatic islets using unbiased chromatin immunoprecipitation coupled with next-generation sequencing (ChIP-seq). Integrative analysis of gene expression profiles and histone H3K4me3 levels identified a number of transcripts and target genes dependent on menin. In the absence of Men1, histone H3K27me3 levels are enriched, with a concomitant decrease in H3K4me3 within the promoters of these target genes. In particular, expression of the insulin-like growth factor 2 mRNA binding protein 2 (IGF2BP2) gene is subject to dynamic epigenetic regulation by Men1-dependent histone modification in a time-dependent manner. Decreased expression of IGF2BP2 in Men1-deficient hyperplastic pancreatic islets is partially reversed by ablation of RBP2 (KDM5A), a histone H3K4-specific demethylase of the jumonji, AT-rich interactive domain 1 (JARID1) family. Taken together, these data demonstrate that loss of Men1 in pancreatic islet cells alters the epigenetic landscape of its target genes.

Implications: Epigenetic profiling and gene expression analysis in Men1-deficient pancreatic islet cells reveals vital insight into the molecular events that occur during the progression of pancreatic islet tumorigenesis. Mol Cancer Res; 13(4); 689–98. ©2014 AACR.
Data from VDR Activity Is Differentially Affected by Hic-5 in Prostate Cancer and Stromal Cells
Authors: Solomon Joshua D. , Heitzer Marjet D. , Liu Teresa T. , Beumer Jan H. , Parise Robert A. , Normolle Daniel P. , Leach Damien A. , Buchanan Grant , DeFranco Donald B.
Published: March 2024

Abstract
Patients with prostate cancer treated with androgen deprivation therapy (ADT) eventually develop castrate-resistant prostate cancer (CRPC). 1,25-Dihydroxyvitamin D3 (1,25D3/calcitriol) is a potential adjuvant therapy that confers antiproliferative and pro-differentiation effects in vitro, but has had mixed results in clinical trials. The impact of the tumor microenvironment on 1,25D3 therapy in patients with CRPC has not been assessed. Transforming growth factor β (TGFβ), which is associated with the development of tumorigenic “reactive stroma” in prostate cancer, induced vitamin D3 receptor (VDR) expression in the human WPMY-1 prostate stromal cell line. Similarly, TGFβ enhanced 1,25D3-induced upregulation of CYP24A1, which metabolizes 1,25D3 and thereby limits VDR activity. Ablation of Hic-5, a TGFβ-inducible nuclear receptor coregulator, inhibited basal VDR expression, 1,25D3-induced CYP24A1 expression and metabolism of 1,25D3 and TGFβ-enhanced CYP24A1 expression. A Hic-5–responsive sequence was identified upstream (392–451 bp) of the CYP24A1 transcription start site that is occupied by VDR only in the presence of Hic-5. Ectopic expression of Hic-5 sensitized LNCaP prostate tumor cells to growth-inhibitory effects of 1,25D3 independent of CYP24A1. The sensitivity of Hic-5–expressing LNCaP cells to 1,25D3-induced growth inhibition was accentuated in coculture with Hic-5–ablated WPMY-1 cells. Therefore, these findings indicate that the search for mechanisms to sensitize prostate cancer cells to the antiproliferative effects of VDR ligands needs to account for the impact of VDR activity in the tumor microenvironment.

Implications: Hic-5 acts as a coregulator with distinct effects on VDR transactivation, in prostate cancer and stromal cells, and may exert diverse effects on adjuvant therapy designed to exploit VDR activity in prostate cancer. Mol Cancer Res; 12(8); 1166–80. ©2014 AACR.
Data from Sprouty2 Drives Drug Resistance and Proliferation in Glioblastoma
Authors: Walsh Alice M. , Kapoor Gurpreet S. , Buonato Janine M. , Mathew Lijoy K. , Bi Yingtao , Davuluri Ramana V. , Martinez-Lage Maria , Simon M. Celeste , O'Rourke Donald M. , Lazzara Matthew J.
Published: March 2024

Abstract
Glioblastoma multiforme (GBM) is notoriously resistant to therapy, and the development of a durable cure will require the identification of broadly relevant regulators of GBM cell tumorigenicity and survival. Here, we identify Sprouty2 (SPRY2), a known regulator of receptor tyrosine kinases (RTK), as one such regulator. SPRY2 knockdown reduced proliferation and anchorage-independent growth in GBM cells and slowed xenograft tumor growth in mice. SPRY2 knockdown also promoted cell death in response to coinhibition of the epidermal growth factor receptor (EGFR) and the c-MET receptor in GBM cells, an effect that involved regulation of the ability of the p38 mitogen-activated protein kinase (MAPK) to drive cell death in response to inhibitors. Analysis of data from clinical tumor specimens further demonstrated that SPRY2 protein is definitively expressed in GBM tissue, that SPRY2 expression is elevated in GBM tumors expressing EGFR variant III (EGFRvIII), and that elevated SPRY2 mRNA expression portends reduced GBM patient survival. Overall, these results identify SPRY2 and the pathways it regulates as novel candidate biomarkers and therapeutic targets in GBM.

Implications: SPRY2, counter to its roles in other cancer settings, promotes glioma cell and tumor growth and cellular resistance to targeted inhibitors of oncogenic RTKs, thus making SPRY2 and the cell signaling processes it regulates potential novel therapeutic targets in glioma. Mol Cancer Res; 13(8); 1227–37. ©2015 AACR.
Data from Endophilin A2 Promotes TNBC Cell Invasion and Tumor Metastasis
Authors: Baldassarre Tomas , Watt Kathleen , Truesdell Peter , Meens Jalna , Schneider Mark M. , Sengupta Sandip K. , Craig Andrew W.
Published: March 2024

Abstract
Triple-negative breast cancers (TNBCs) are highly aggressive cancers that lack targeted therapies. However, EGFR is frequently activated in a subset of TNBCs and represents a viable clinical target. Because the endocytic adaptor protein Endophilin A2 (SH3GL1/Endo II) has been implicated in EGFR internalization, we investigated Endo II expression and function in human TNBCs. Endo II expression was high in several TNBC cells compared with normal breast epithelial cells. Stable knockdown (KD) of Endo II was achieved in two TNBC cell lines, and although cell viability was unaffected, defects in receptor-mediated endocytosis were observed. EGFR signaling to Erk and Akt kinases was impaired in Endo II KD cells, and this correlated with reduced rates of EGFR internalization and cell motility. Endo II KD cells also displayed defects in three dimensional (3D) cell invasion, and this correlated with impaired extracellular matrix degradation and internalization of MT1-MMP. Endo II silencing also caused a significant reduction in TNBC tumor growth and lung metastasis in mammary orthotopic tumor xenograft assays. In human breast tumor specimens, Endo II expression was highest in TNBC tumors compared with other subtypes, and at the level of gene expression, high Endo II was associated with reduced relapse-free survival in patients with basal-like breast cancers. Together, these results identify a positive role for Endo II in TNBC tumor metastasis and a potential link with poor prognosis.

Implications: Endophilin A2 and related adaptor proteins represent important signaling hubs to target in metastatic cancers. Mol Cancer Res; 13(6); 1044–55. ©2015 AACR.
Data from SOCS3 Modulates the Response to Enzalutamide and Is Regulated by Androgen Receptor Signaling and CpG Methylation in Prostate Cancer Cells
Authors: Handle Florian , Erb Holger H.H. , Luef Birgit , Hoefer Julia , Dietrich Dimo , Parson Walther , Kristiansen Glen , Santer Frédéric R. , Culig Zoran
Published: March 2024

Abstract
The proinflammatory cytokine IL6 is associated with bad prognosis in prostate cancer and implicated in progression to castration resistance. Suppressor of cytokine signaling 3 (SOCS3) is an IL6-induced negative feedback regulator of the IL6/Janus kinase (JAK)/STAT3 pathway. This study reveals that the SOCS3 promoter is hypermethylated in cancerous regions compared with adjacent benign tissue in prostate cancer using methylation-specific qPCR. A series of in vitro experiments was performed to assess the functional impact of low SOCS3 expression during anti-androgen treatment. Using lentivirus-mediated knockdown, it was demonstrated for the first time that SOCS3 regulates IL6/JAK/STAT3 signaling in androgen receptor–positive LNCaP cells. In addition, SOCS3 mRNA is upregulated by the anti-androgens bicalutamide and enzalutamide. This effect is caused by androgen receptor–mediated suppression of IL6ST and JAK1 expression, which leads to altered STAT3 signaling. Functionally, knockdown of SOCS3 led to enhanced androgen receptor activity after 3 weeks of enzalutamide treatment in an inflammatory setting. Furthermore, the stemness/self-renewal associated genes SOX2 and NANOG were strongly upregulated by the long-term treatment, and modulation of SOCS3 expression was sufficient to counteract this effect. These findings prove that SOCS3 plays an important role during anti-androgen treatment in an inflammatory environment.

Implications:SOCS3 is frequently inactivated by promoter hypermethylation in prostate cancer, which disrupts the feedback regulation of IL6 signaling and leads to reduced efficacy of enzalutamide in the presence of inflammatory cytokines. Mol Cancer Res; 14(6); 574–85. ©2016 AACR.
Data from AXL Is a Putative Tumor Suppressor and Dormancy Regulator in Prostate Cancer
Authors: Axelrod Haley D. , Valkenburg Kenneth C. , Amend Sarah R. , Hicks Jessica L. , Parsana Princy , Torga Gonzalo , DeMarzo Angelo M. , Pienta Kenneth J.
Published: March 2024

Abstract
Prostate cancer bone metastasis remains lethal and incurable, and often arises years after elimination of the primary tumor. It is unclear what underlies the decades-long clinical latency before recurrence, but evidence points to the existence of dormant residual tumor cells that disseminated before the primary tumor was eliminated. To design therapies to prevent progression of disseminated tumor cells (DTC) into lethal metastases, it is crucial to understand the mechanism(s) underlying this dormancy. The current study functionally validated our previous observation that implicated the GAS6/AXL axis in mediating DTC dormancy in the bone marrow. AXL-null and AXL-overexpressing prostate cancer cell lines were generated to determine if AXL was necessary and/or sufficient for dormancy. Characterization of these cells in vitro and using in vivo mouse models of DTC growth demonstrated that AXL was indeed sufficient to induce dormancy, but was unable to maintain it long-term and was not absolutely required for a dormancy period. Clinically, AXL expression correlated with longer survival in prostate cancer patients, and AXL was not expressed by cancer cells in primary or metastatic tissue. These data point to a tumor-suppressive role for AXL in prostate cancer, and future work is required to determine if AXL is expressed on human bone marrow DTCs.
Implications:
The ability of AXL to initiate but not maintain dormancy, coupled with its dispensability, suggests that targeting AXL alone will not prevent lethal metastatic outgrowth, and likely a cooperative network of factors exists to mediate long-term cellular dormancy.
Data from Ercc1 Deficiency Promotes Tumorigenesis and Increases Cisplatin Sensitivity in a Tp53 Context-Specific Manner
Authors: Jokić Mladen , Vlašić Ignacija , Rinneburger Miriam , Klümper Niklas , Spiro Judith , Vogel Wenzel , Offermann Anne , Kümpers Christiane , Fritz Christian , Schmitt Anna , Riabinska Arina , Wittersheim Maike , Michels Sebastian , Ozretić Luka , Florin Alexandra , Welcker Daniela , Akyuz Mehmet Deniz , Nowak Michael , Erkel Martin , Wolf Jürgen , Büttner Reinhard , Schumacher Björn , Thomale Jürgen , Persigehl Thorsten , Maintz David , Perner Sven , Reinhardt Hans Christian
Published: March 2024

Abstract
KRAS-mutant lung adenocarcinoma is among the most common cancer entities and, in advanced stages, typically displays poor prognosis due to acquired resistance against chemotherapy, which is still largely based on cisplatin-containing combination regimens. Mechanisms of cisplatin resistance have been extensively investigated, and ERCC1 has emerged as a key player due to its central role in the repair of cisplatin-induced DNA lesions. However, clinical data have not unequivocally confirmed ERCC1 status as a predictor of the response to cisplatin treatment. Therefore, we employed an autochthonous mouse model of Kras-driven lung adenocarcinoma resembling human lung adenocarcinoma to investigate the role of Ercc1 in the response to cisplatin treatment. Our data show that Ercc1 deficiency in Tp53-deficient murine lung adenocarcinoma induces a more aggressive tumor phenotype that displays enhanced sensitivity to cisplatin treatment. Furthermore, tumors that relapsed after cisplatin treatment in our model develop a robust etoposide sensitivity that is independent of the Ercc1 status and depends solely on previous cisplatin exposure. Our results provide a solid rationale for further investigation of the possibility of preselection of lung adenocarcinoma patients according to the functional ERCC1- and mutational TP53 status, where functionally ERCC1-incompetent patients might benefit from sequential cisplatin and etoposide chemotherapy.

Implications: This study provides a solid rationale for the stratification of lung adenocarcinoma patients according to the functional ERCC1- and mutational TP53 status, where functionally ERCC1-incompetent patients could benefit from sequential cisplatin and etoposide chemotherapy. Mol Cancer Res; 14(11); 1110–23. ©2016 AACR.