bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Epigenetic Regulation of ZBTB18 Promotes Glioblastoma Progression
Authors: Fedele Vita , Dai Fangping , Masilamani Anie P. , Heiland Dieter H. , Kling Eva , Gätjens-Sanchez Ana M. , Ferrarese Roberto , Platania Leonardo , Doostkam Soroush , Kim Hyunsoo , Nelander Sven , Weyerbrock Astrid , Prinz Marco , Califano Andrea , Iavarone Antonio , Bredel Markus , Carro Maria S.
Published: March 2024

Abstract
Glioblastoma (GBM) comprises distinct subtypes characterized by their molecular profile. Mesenchymal identity in GBM has been associated with a comparatively unfavorable prognosis, primarily due to inherent resistance of these tumors to current therapies. The identification of molecular determinants of mesenchymal transformation could potentially allow for the discovery of new therapeutic targets. Zinc Finger and BTB Domain Containing 18 (ZBTB18/ZNF238/RP58) is a zinc finger transcriptional repressor with a crucial role in brain development and neuronal differentiation. Here, ZBTB18 is primarily silenced in the mesenchymal subtype of GBM through aberrant promoter methylation. Loss of ZBTB18 contributes to the aggressive phenotype of glioblastoma through regulation of poor prognosis–associated signatures. Restitution of ZBTB18 expression reverses the phenotype and impairs tumor-forming ability. These results indicate that ZBTB18 functions as a tumor suppressor in GBM through the regulation of genes associated with phenotypically aggressive properties.

Implications: This study characterizes the role of the putative tumor suppressor ZBTB18 and its regulation by promoter hypermethylation, which appears to be a common mechanism to silence ZBTB18 in the mesenchymal subtype of GBM and provides a new mechanistic opportunity to specifically target this tumor subclass. Mol Cancer Res; 15(8); 998–1011. ©2017 AACR.
Data from KRAS Activation in Gastric Adenocarcinoma Stimulates Epithelial-to-Mesenchymal Transition to Cancer Stem–Like Cells and Promotes Metastasis
Authors: Yoon Changhwan , Till Jacob , Cho Soo-Jeong , Chang Kevin K. , Lin Jian-xian , Huang Chang-ming , Ryeom Sandra , Yoon Sam S.
Published: March 2024

Abstract
Our previous work showed that in a mouse model of gastric adenocarcinoma with loss of p53 and Cdh1 that adding oncogenic Kras (a.k.a. Tcon mice) accelerates tumorigenesis and metastasis. Here, we sought to examine KRAS activation in epithelial-to-mesenchymal transition (EMT) and generation of cancer stem–like cells (CSC). Transduction of nontransformed HFE-145 gastric epithelial cells with oncogenic KRASG12V significantly decreased expression of the epithelial marker E-cadherin, increased expression of the mesenchymal marker vimentin and the EMT transcription factor Slug, and increased migration and invasion by 15- to 17-fold. KRASG12V also increased expression of self-renewal proteins such as Sox2 and increased spheroid formation by 2.6-fold. In tumor-derived organoids from Tcon mice, Kras knockdown decreased spheroid formation, expression of EMT-related proteins, migration, and invasion; similar effects, as well as reversal of chemoresistance, were observed following KRAS knockdown or MEK inhibition in patient tumor-derived gastric adenocarcinoma cell lines (AGS and KATOIII). KRAS inhibition in gastric adenocarcinoma spheroid cells led to reduced AGS flank xenograft growth, loss of the infiltrative tumor border, fewer lung metastases, and increased survival. In a tissue microarray of human gastric adenocarcinomas from 115 patients, high tumor levels of CD44 (a marker of CSCs) and KRAS activation were independent predictors of worse overall survival. In conclusion, KRAS activation in gastric adenocarcinoma cells stimulates EMT and transition to CSCs, thus promoting metastasis.
Implications:
This study provides rationale for examining inhibitors of KRAS to block metastasis and reverse chemotherapy resistance in gastric adenocarcinoma patients.
Data from Mitotic DNA Synthesis Is Differentially Regulated between Cancer and Noncancerous Cells
Authors: Graber-Feesl Cari L. , Pederson Kayla D. , Aney Katherine J. , Shima Naoko
Published: March 2024

Abstract
Mitotic DNA synthesis is a recently discovered mechanism that resolves late replication intermediates, thereby supporting cell proliferation under replication stress. This unusual form of DNA synthesis occurs in the absence of RAD51 or BRCA2, which led to the identification of RAD52 as a key player in this process. Notably, mitotic DNA synthesis is predominantly observed at chromosome loci that colocalize with FANCD2 foci. However, the role of this protein in mitotic DNA synthesis remains largely unknown. In this study, we investigated the role of FANCD2 and its interplay with RAD52 in mitotic DNA synthesis using aphidicolin as a universal inducer of this process. After examining eight human cell lines, we provide evidence for FANCD2 rather than RAD52 as a fundamental supporter of mitotic DNA synthesis. In cancer cell lines, FANCD2 exerts this role independently of RAD52. Surprisingly, RAD52 is dispensable for mitotic DNA synthesis in noncancerous cell lines, but these cells strongly depend on FANCD2 for this process. Therefore, RAD52 functions selectively in cancer cells as a secondary regulator in addition to FANCD2 to facilitate mitotic DNA synthesis. As an alternative to aphidicolin, we found partial inhibition of origin licensing as an effective way to induce mitotic DNA synthesis preferentially in cancer cells. Importantly, cancer cells still perform mitotic DNA synthesis by dual regulation of FANCD2 and RAD52 under such conditions.
Implications:
These key differences in mitotic DNA synthesis between cancer and noncancerous cells advance our understanding of this mechanism and can be exploited for cancer therapies.
Data from A Ca2+-ATPase Regulates E-cadherin Biogenesis and Epithelial–Mesenchymal Transition in Breast Cancer Cells
Authors: Dang Donna K. , Makena Monish Ram , Llongueras José P. , Prasad Hari , Ko Myungjun , Bandral Manuj , Rao Rajini
Published: March 2024

Abstract
Progression of benign tumors to invasive, metastatic cancer is accompanied by the epithelial-to-mesenchymal transition (EMT), characterized by loss of the cell-adhesion protein E-cadherin. Although silencing mutations and transcriptional repression of the E-cadherin gene have been widely studied, not much is known about posttranslational regulation of E-cadherin in tumors. We show that E-cadherin is tightly coexpressed with the secretory pathway Ca2+-ATPase isoform 2, SPCA2 (ATP2C2), in breast tumors. Loss of SPCA2 impairs surface expression of E-cadherin and elicits mesenchymal gene expression through disruption of cell adhesion in tumorspheres and downstream Hippo-YAP signaling. Conversely, ectopic expression of SPCA2 in triple-negative breast cancer elevates baseline Ca2+ and YAP phosphorylation, enhances posttranslational expression of E-cadherin, and suppresses mesenchymal gene expression. Thus, loss of SPCA2 phenocopies loss of E-cadherin in the Hippo signaling pathway and EMT–MET transitions, consistent with a functional role for SPCA2 in E-cadherin biogenesis. Furthermore, we show that SPCA2 suppresses invasive phenotypes, including cell migration in vitro and tumor metastasis in vivo. Based on these findings, we propose that SPCA2 functions as a key regulator of EMT and may be a potential therapeutic target for treatment of metastatic cancer.
Implications:
Posttranslational control of E-cadherin and the Hippo pathway by calcium signaling regulates EMT in breast cancer cells.
Data from A First-in-Class TWIST1 Inhibitor with Activity in Oncogene-Driven Lung Cancer
Authors: Yochum Zachary A. , Cades Jessica , Mazzacurati Lucia , Neumann Neil M. , Khetarpal Susheel K. , Chatterjee Suman , Wang Hailun , Attar Myriam A. , Huang Eric H.-B. , Chatley Sarah N. , Nugent Katriana , Somasundaram Ashwin , Engh Johnathan A. , Ewald Andrew J. , Cho Yoon-Jae , Rudin Charles M. , Tran Phuoc T. , Burns Timothy F.
Published: March 2024

Abstract
TWIST1, an epithelial–mesenchymal transition (EMT) transcription factor, is critical for oncogene-driven non–small cell lung cancer (NSCLC) tumorigenesis. Given the potential of TWIST1 as a therapeutic target, a chemical–bioinformatic approach using connectivity mapping (CMAP) analysis was used to identify TWIST1 inhibitors. Characterization of the top ranked candidates from the unbiased screen revealed that harmine, a harmala alkaloid, inhibited multiple TWIST1 functions, including single-cell dissemination, suppression of normal branching in 3D epithelial culture, and proliferation of oncogene driver-defined NSCLC cells. Harmine treatment phenocopied genetic loss of TWIST1 by inducing oncogene-induced senescence or apoptosis. Mechanistic investigation revealed that harmine targeted the TWIST1 pathway through its promotion of TWIST1 protein degradation. As dimerization is critical for TWIST1 function and stability, the effect of harmine on specific TWIST1 dimers was examined. TWIST1 and its dimer partners, the E2A proteins, which were found to be required for TWIST1-mediated functions, regulated the stability of the other heterodimeric partner posttranslationally. Harmine preferentially promoted degradation of the TWIST1-E2A heterodimer compared with the TWIST-TWIST1 homodimer, and targeting the TWIST1-E2A heterodimer was required for harmine cytotoxicity. Finally, harmine had activity in both transgenic and patient-derived xenograft mouse models of KRAS-mutant NSCLC. These studies identified harmine as a first-in-class TWIST1 inhibitor with marked anti-tumor activity in oncogene-driven NSCLC including EGFR mutant, KRAS mutant and MET altered NSCLC.

Implications: TWIST1 is required for oncogene-driven NSCLC tumorigenesis and EMT; thus, harmine and its analogues/derivatives represent a novel therapeutic strategy to treat oncogene-driven NSCLC as well as other solid tumor malignancies. Mol Cancer Res; 15(12); 1764–76. ©2017 AACR.
Data from Activation of PPARγ in Myeloid Cells Promotes Progression of Epithelial Lung Tumors through TGFβ1
Authors: Sippel Trisha R. , Johnson Amber M. , Li Howard Y. , Hanson Dwight , Nguyen Teresa T. , Bullock Bonnie L. , Poczobutt Joanna M. , Kwak Jeff W. , Kleczko Emily K. , Weiser-Evans Mary C. , Nemenoff Raphael A.
Published: March 2024

Abstract
Lung cancer is a heterogeneous disease in which patient-specific treatments are desirable and the development of targeted therapies has been effective. Although mutations in KRAS are frequent in lung adenocarcinoma, there are currently no targeted agents against KRAS. Using a mouse lung adenocarcinoma cell line with a Kras mutation (CMT167), we previously showed that PPARγ activation in lung cancer cells inhibits cell growth in vitro yet promotes tumor progression when activated in myeloid cells of the tumor microenvironment. Here, we report that PPARγ activation in myeloid cells promotes the production of TGFβ1, which, in turn, acts on CMT167 cancer cells to increase migration and induce an epithelial–mesenchymal transition (EMT). Targeting TGFβ1 signaling in CMT167 cells prevented their growth and metastasis in vivo. Similarly, another mouse lung adenocarcinoma cell line with a Kras mutation, LLC, induced TGFβ1 in myeloid cells through PPARγ activation. However, LLC cells are more mesenchymal and did not undergo EMT in response to TGFβ1, nor did LLC require TGFβ1 signaling for metastasis in vivo. Converting CMT167 cells to a mesenchymal phenotype through overexpression of ZEB1 made them unresponsive to TGFβ1 receptor inhibition. The ability of TGFβ1 to induce EMT in lung tumors may represent a critical process in cancer progression. We propose that TGFβ receptor inhibition could provide an additional treatment option for KRAS-mutant epithelial lung tumors.

Implications: This study suggests that TGFβ receptor inhibitors may be an effective therapy in a subset of KRAS-mutant patients with non–small cell lung cancer, which show an epithelial phenotype.
Data from Targeting CREB Pathway Suppresses Small Cell Lung Cancer
Authors: Xia Yifeng , Zhan Cheng , Feng Mingxiang , Leblanc Mathias , Ke Eugene , Yeddula Narayana , Verma Inder M.
Published: March 2024

Abstract
Small cell lung cancer (SCLC) is the most deadly subtype of lung cancer due to its dismal prognosis. We have developed a lentiviral vector-mediated SCLC mouse model and have explored the role of both the NF-κB and CREB families of transcription factors in this model. Surprisingly, induction of NF-κB activity, which promotes tumor progression in many cancer types including non–small cell lung carcinoma (NSCLC), is dispensable in SCLC. Instead, suppression of NF-κB activity in SCLC tumors moderately accelerated tumor development. Examination of gene expression signatures of both mouse and human SCLC tumors revealed overall low NF-κB but high CREB activity. Blocking CREB activation by a dominant-negative form of PKA (dnPKA) completely abolished the development of SCLC. Similarly, expression of dnPKA or treatment with PKA inhibitor H89 greatly reduced the growth of SCLC tumors in syngeneic transplantation models. Altogether, our results strongly suggest that targeting CREB is a promising therapeutic strategy against SCLC.

Implications: Activity of the transcription factor CREB is elevated in SCLC tumors, which helps to maintain its neuroendocrine signature and cell proliferation. Our results highlight the importance of targeting the CREB pathway to develop new therapeutics to combat SCLC. Mol Cancer Res; 16(5); 825–32. ©2018 AACR.
Data from Nucleome Analysis Reveals Structure–Function Relationships for Colon Cancer
Authors: Seaman Laura , Chen Haiming , Brown Markus , Wangsa Darawalee , Patterson Geoff , Camps Jordi , Omenn Gilbert S. , Ried Thomas , Rajapakse Indika
Published: March 2024

Abstract
Chromosomal translocations and aneuploidy are hallmarks of cancer genomes; however, the impact of these aberrations on the nucleome (i.e., nuclear structure and gene expression) is not yet understood. Here, the nucleome of the colorectal cancer cell line HT-29 was analyzed using chromosome conformation capture (Hi-C) to study genome structure, complemented by RNA sequencing (RNA-seq) to determine the consequent changes in genome function. Importantly, translocations and copy number changes were identified at high resolution from Hi-C data and the structure–function relationships present in normal cells were maintained in cancer. In addition, a new copy number–based normalization method for Hi-C data was developed to analyze the effect of chromosomal aberrations on local chromatin structure. The data demonstrate that at the site of translocations, the correlation between chromatin organization and gene expression increases; thus, chromatin accessibility more directly reflects transcription. In addition, the homogeneously staining region of chromosome band 8q24 of HT-29, which includes the MYC oncogene, interacts with various loci throughout the genome and is composed of open chromatin. The methods, described herein, can be applied to the assessment of the nucleome in other cell types with chromosomal aberrations.

Implications: Findings show that chromosome conformation capture identifies chromosomal abnormalities at high resolution in cancer cells and that these abnormalities alter the relationship between structure and function. Mol Cancer Res; 15(7); 821–30. ©2017 AACR.
Data from Near-Infrared Photoimmunotherapy Targeting Prostate Cancer with Prostate-Specific Membrane Antigen (PSMA) Antibody
Authors: Nagaya Tadanobu , Nakamura Yuko , Okuyama Shuhei , Ogata Fusa , Maruoka Yasuhiro , Choyke Peter L. , Kobayashi Hisataka
Published: March 2024

Abstract
Prostate-specific membrane antigen (PSMA) is a membrane protein that is overexpressed manifold in prostate cancer and provides an attractive target for molecular therapy. Near-infrared photoimmunotherapy (NIR-PIT) is a highly selective tumor treatment that employs an antibody-photoabsorber conjugate (APC). Here, we describe the efficacy of NIR-PIT, using a fully human IgG1 anti-PSMA monoclonal antibody (mAb), conjugated to the photoabsorber, IR700DX, in a PSMA-expressing PC3 prostate cancer cell line. Anti-PSMA-IR700 showed specific binding and cell-specific killing was observed after exposure of the cells to NIR light in vitro. In the in vivo study, anti-PSMA-IR700 showed high tumor accumulation and high tumor–background ratio. Tumor-bearing mice were separated into 4 groups: (i) no treatment; (ii) 100 μg of anti-PSMA-IR700 i.v.; (iii) NIR light exposure; (iv) 100 μg of anti-PSMA-IR700 i.v., NIR light exposure was administered. These were performed every week for up to 3 weeks. Tumor growth was significantly inhibited by NIR-PIT treatment compared with the other control groups (P < 0.001), and significantly prolonged survival was achieved (P < 0.0001 vs. other control groups). More than two thirds of tumors were cured with NIR-PIT. In conclusion, the anti-PSMA antibody is suitable as an APC for NIR-PIT. Furthermore, NIR-PIT with the anti-PSMA-IR700 antibody is a promising candidate of the treatment of PSMA-expressing tumors and could be readily translated to humans.

Implications: NIR-infrared photoimmunotherapy (NIR-PIT) using a fully human anti-PSMA-IR700 conjugate showed potential therapeutic effects against a PSMA-expressing prostate cancer that is readily translated to humans. Mol Cancer Res; 15(9); 1153–62. ©2017 AACR.
Data from Atorvastatin Decreases HBx-Induced Phospho-Akt in Hepatocytes via P2X Receptors
Authors: Ghalali Aram , Martin-Renedo Javier , Högberg Johan , Stenius Ulla
Published: March 2024

Abstract
Hepatocellular carcinoma (HCC) is rated as the fifth most common malignancy and third in cancer-related deaths worldwide. Statins, HMG-CoA reductase inhibitors, are potent cholesterol-lowering drugs, and recent epidemiologic evidence suggests that statins prevent aggressive HCC development. Previous experiments revealed that statins downregulate phosphorylated Akt (pAkt). Here, it is demonstrated that atorvastatin decreases nuclear pAkt levels in pancreatic and lung cancer cell lines within minutes, and this rapid effect is mediated by the purinergic P2X receptors. Akt is upregulated by hepatitis viruses and has oncogenic activity in HCC; therefore, we tested the possibility that the P2X–Akt pathway is important for the anticipated anticancer effects of statins in hepatocytes. Atorvastatin decreased hepatitis B virus X protein- and insulin-induced pAkt and pGsk3β (Ser9) levels. Furthermore, Akt-induced lipogenesis was counteracted by atorvastatin, and these statin-induced effects were dependent on P2X receptors. Statin also decreased proliferation and invasiveness of hepatocytes. These data provide mechanistic evidence for a P2X receptor–dependent signaling pathway by which statins decrease pAkt, its downstream phosphorylation target pGsk3β, and lipogenesis in hepatocytes.

Implications: The Akt pathway is deregulated and may act as a driver in HCC development; the P2X–Akt signaling pathway may have a role in anticancer effects of statins. Mol Cancer Res; 15(6); 714–22. ©2017 AACR.
Data from Exosomes from HNSCC Promote Angiogenesis through Reprogramming of Endothelial Cells
Authors: Ludwig Nils , Yerneni Saigopalakrishna S. , Razzo Beatrice M. , Whiteside Theresa L.
Published: March 2024

Abstract
For solid tumors, such as head and neck squamous cell carcinoma (HNSCC), an adequate blood supply is of critical importance for tumor development and metastasis. Tumor-derived exosomes (TEX) accumulate in the tumor microenvironment (TME) and serve as a communication system between tumor and normal stromal cells. This study evaluates in vitro and in vivo effects mediated by TEX that result in promotion of angiogenesis. TEX produced by PCI-13 (HPV−) and UMSCC47 (HPV+) cell lines or from plasma of HNSCC patients were isolated by mini size exclusion chromatography (mini-SEC). TEX morphology, size, numbers, and molecular profile were characterized, and the angiogenesis-inducing potential was measured in arrays and real-time PCR with human endothelial cells (HUVEC). Uptake of labeled TEX by HUVECs was demonstrated by confocal microscopy. Tube formation, proliferation, migration, and adherence by HUVECs in response to TEX were investigated. The 4-nitroquinoline-1-oxide (4-NQO) oral carcinogenesis mouse model was used to confirm that TEX induce the same results in vivo. TEX were found to be potent inducers of angiogenesis in vitro and in vivo through functional reprogramming and phenotypic modulation of endothelial cells. TEX carried angiogenic proteins and were internalized by HUVECs within 4 hours. TEX stimulated proliferation (P < 0.001), migration (P < 0.05), and tube formation (P < 0.001) by HUVECs and promoted formation of defined vascular structures in vivo. The data suggest that TEX promote angiogenesis and drive HNSCC progression. Future efforts should focus on eliminating or silencing TEX and thereby adding new options for improving existing antiangiogenic therapies.

Implications: TEX appear to play an important role in tumor angiogenesis and thus may contribute to tumor growth and metastasis of HNSCC in this context. Mol Cancer Res; 16(11); 1798–808. ©2018 AACR.
Data from Therapeutic Targeting of PTK7 is Cytotoxic in Atypical Teratoid Rhabdoid Tumors
Authors: Messerli Shanta M. , Hoffman Mariah M. , Gnimpieba Etienne Z. , Bhardwaj Ratan D.
Published: March 2024

Abstract
Novel discoveries involving the evaluation of potential therapeutics are based on newly identified molecular targets for atypical teratoid rhabdoid tumors (ATRT), which are the most common form of infantile brain tumors. Central nervous system ATRTs are rare, aggressive, and fast growing tumors of the brain and spinal cord and carry a very poor prognosis. Currently, the standard of care for ATRT patients is based on surgical resection followed by systemic chemotherapy and radiotherapy, which result in severe side effects. As protein tyrosine kinases have proven to be actionable targets that reduce tumor growth in a number of cancers, we examined how inhibiting tyrosine kinases affected ATRT tumor growth. Here, we examine the therapeutic efficacy of the broad-spectrum tyrosine kinase inhibitor vatalanib in the treatment of ATRT. Vatalanib significantly reduced the growth of ATRT tumor cell lines, both in two-dimensional cell culture and in three-dimensional cell culture using a spheroid model. As vatalanib had a remarkable effect on the growth of ATRT, we decided to use a transcriptomic approach to therapy by examining new actionable targets, such as tyrosine kinases. Next-generation RNA-sequencing and NanoString data analysis showed a significant increase in PTK7 RNA expression levels in ATRT tumors. Inhibition of PTK7 by siRNA treatment significantly decreases the viability of ATRT patient–derived tumor cell lines.

Implications: These studies provide the groundwork for future preclinical in vivo studies aiming to investigate the efficacy of PTK7 inhibition on ATRT tumor growth. Mol Cancer Res; 15(8); 973–83. ©2017 AACR.
Data from Hypoxia-Associated Factor (HAF) Mediates Neurofibromin Ubiquitination and Degradation Leading to Ras–ERK Pathway Activation in Hypoxia
Authors: Green Yangsook Song , Sargis Timothy , Reichert Ethan Conrad , Rudasi Eleanor , Fuja Daniel , Jonasch Eric , Koh Mei Yee
Published: March 2024

Abstract
Low oxygen or hypoxia is a feature of all solid tumors and has been associated with aggressive disease. Here, we describe a novel mechanism for the hypoxia-dependent degradation of the Ras-GTPase–activating protein neurofibromin, by hypoxia-associated factor (HAF). We have previously characterized HAF as an oxygen-independent ubiquitin ligase for HIF-1α. Here, we show that HAF promotes neurofibromin ubiquitination and degradation independently of oxygen and pVHL, resulting in Ras–ERK pathway activation. Hypoxia enhanced HAF:neurofibromin binding independently of HAF-SUMOylation, whereas HAF knockdown increased neurofibromin levels primarily in hypoxia, supporting the role of HAF as a hypoxia-specific neurofibromin regulator. HAF overexpression increased p-ERK levels and promoted resistance of clear cell kidney cancer (ccRCC) cells to sorafenib and sunitinib in both normoxia and hypoxia. However, a greater-fold increase in sorafenib/sunitinib resistance was observed during hypoxia, particularly in pVHL-deficient cells. Intriguingly, HAF-mediated resistance was HIF-2α–dependent in normoxia, but HIF-2α–independent in hypoxia indicating two potential mechanisms of HAF-mediated resistance: a HIF-2α–dependent pathway dominant in normoxia, and the direct activation of the Ras–ERK pathway through neurofibromin degradation dominant in hypoxia. Patients with ccRCC with high HAF transcript or protein levels showed significantly decreased overall survival compared with those with low HAF. Thus, we establish a novel, nonmutational pathway of neurofibromin inactivation through hypoxia-induced HAF-mediated degradation, leading to Ras–ERK activation and poor prognosis in ccRCC.
Implications:
We describe a novel mechanism of neurofibromin degradation induced by hypoxia that leads to activation of the prooncogenic Ras–ERK pathway and resistance to therapy.
Data from HDAC1 Is a Required Cofactor of CBFβ-SMMHC and a Potential Therapeutic Target in Inversion 16 Acute Myeloid Leukemia
Authors: Richter Lisa E. , Wang Yiqian , Becker Michelle E. , Coburn Rachel A. , Williams Jacob T. , Amador Catalina , Hyde R. Katherine
Published: March 2024

Abstract
Acute myeloid leukemia (AML) is a neoplastic disease characterized by the uncontrolled proliferation and accumulation of immature myeloid cells. A common mutation in AML is the inversion of chromosome 16 [inv (16)], which generates a fusion between the genes for core binding factor beta (CBFB) and smooth muscle myosin heavy chain gene (MYH11), forming the oncogene CBFB-MYH11. The expressed protein, CBFβ-SMMHC, forms a heterodimer with the key hematopoietic transcription factor RUNX1. Although CBFβ-SMMHC was previously thought to dominantly repress RUNX1, recent work suggests that CBFβ-SMMHC functions together with RUNX1 to activate transcription of specific target genes. However, the mechanism of this activity or a requirement for additional cofactors is not known. Here, we show that the epigenetic regulator histone deacetylase 1 (HDAC1) forms a complex with CBFβ-SMMHC, colocalizes with RUNX1 and CBFβ-SMMHC on the promoters of known fusion protein target genes, and that Hdac1 is required for expression of these genes. These results imply that HDAC1 is an important component of the CBFβ-SMMHC transcriptional complex, and that leukemia cells expressing the fusion protein may be sensitive to treatment with HDAC1 inhibitors. Using a knock-in mouse model expressing CBFβ-SMMHC, we found that in vivo treatment with the HDAC1 inhibitor entinostat decreased leukemic burden, and induced differentiation and apoptosis of leukemia cells. Together, these results demonstrate that HDAC1 is an important cofactor of CBFβ-SMMHC and a potential therapeutic target in inv (16) AML.
Implications:
This report describes a novel role for HDAC1 as a cofactor for the leukemogenic fusion protein CBFβ-SMMHC and shows that inhibitors of HDAC1 effectively target leukemia cells expressing the fusion protein in vivo.
Data from Inhibiting Integrin β8 to Differentiate and Radiosensitize Glioblastoma-Initiating Cells
Authors: Malric Laure , Monferran Sylvie , Delmas Caroline , Arnauduc Florent , Dahan Perrine , Boyrie Sabrina , Deshors Pauline , Lubrano Vincent , Da Mota Dina Ferreira , Gilhodes Julia , Filleron Thomas , Siegfried Aurore , Evrard Solène , Kowalski-Chauvel Aline , Moyal Elizabeth Cohen-Jonathan , Toulas Christine , Lemarié Anthony
Published: March 2024

Abstract
Glioblastomas (GB) are malignant brain tumors with poor prognosis despite treatment with surgery and radio/chemotherapy. These tumors are defined by an important cellular heterogeneity and notably contain a subpopulation of GB-initiating cells (GIC), which contribute to tumor aggressiveness, resistance, and recurrence. Some integrins are specifically expressed by GICs and could be actionable targets to improve GB treatment. Here, integrin β8 (ITGB8) was identified as a potential selective target in this highly tumorigenic GIC subpopulation. Using several patient-derived primocultures, it was demonstrated that ITGB8 is overexpressed in GICs compared with their differentiated progeny. Furthermore, ITGB8 is also overexpressed in GB, and its overexpression is correlated with poor prognosis and with the expression of several other classic stem cell markers. Moreover, inhibiting ITGB8 diminished several main GIC characteristics and features, including self-renewal ability, stemness, migration potential, and tumor formation capacity. Blockade of ITGB8 significantly impaired GIC cell viability via apoptosis induction. Finally, the combination of radiotherapy and ITGB8 targeting radiosensitized GICs through postmitotic cell death.
Implications:
This study identifies ITGB8 as a new selective marker for GICs and as a promising therapeutic target in combination with chemo/radiotherapy for the treatment of highly aggressive brain tumors.
Data from Landscape of Tumor Mutation Load, Mismatch Repair Deficiency, and PD-L1 Expression in a Large Patient Cohort of Gastrointestinal Cancers
Authors: Salem Mohamed E. , Puccini Alberto , Grothey Axel , Raghavan Derek , Goldberg Richard M. , Xiu Joanne , Korn W. Michael , Weinberg Benjamin A. , Hwang Jimmy J. , Shields Anthony F. , Marshall John L. , Philip Philip A. , Lenz Heinz-Josef
Published: March 2024

Abstract
The efficacy of immunotherapy varies widely among different gastrointestinal cancers. Response to immune checkpoint inhibitors is shown to correlate with tumor mutation load (TML), mismatch repair deficiency (dMMR) status, and programmed cell death-ligand 1 (PD-L1) expression. Herein, we quantify TML, dMMR, and PD-L1 expression and determine their interrelationship in gastrointestinal cancers. Here, a total of 4,125 tumors from 14 different gastrointestinal cancer sites were studied using validated assays. Next-generation sequencing was performed on genomic DNA isolated from formalin-fixed paraffin-embedded tumor specimens using the NextSeq platform. TML was calculated using only somatic nonsynonymous missense mutations sequenced with a 592-gene panel. Microsatellite instability (MSI) was assessed using direct analysis of altered known MSI loci in the target regions of the sequenced genes. PD-L1 expression was analyzed by IHC. Interestingly, right-sided colon and small-bowel adenocarcinomas had the highest prevalence of TML-high tumors (14.6% and 10.2%, respectively). Pancreatic neuroendocrine tumors and gastrointestinal stromal tumors had the lowest rates of TML-high (1.3% and 0%, respectively). TML-high was strongly associated with MSI-H (P < 0.0001). However, all TML-high anal cancers (8.3%) were microsatellite stable (MSS). Higher PD-L1 expression was more likely to be seen in MSI compared with MSS tumors (20.6% vs. 7.8%, P < 0.0001).

Implications: TML-high rate varied widely among gastrointestinal cancers. Although MSI is conceivably the main driver for TML-high, other factors may be involved. Future clinical trials are needed to evaluate whether the integration of TML, MSI, and PD-L1 could better identify potential responders to immunotherapy. Mol Cancer Res; 16(5); 805–12. ©2018 AACR.
Data from Adaptive Resistance to EGFR-Targeted Therapy by Calcium Signaling in NSCLC Cells
Authors: Mulder Celine , Prust Nadine , van Doorn Sander , Reinecke Maria , Kuster Bernhard , van Bergen en Henegouwen Paul , Lemeer Simone
Published: March 2024

Abstract
Targeted therapies against oncogenic receptor tyrosine kinases (RTK) show promising results in the clinic. Unfortunately, despite the initial positive response, most patients develop therapeutic resistance. Most research has focused on acquired resistance occurring after an extensive time of treatment; however, the question remains as to how cells can survive an initial treatment, as early resistance to apoptosis will enable cells to develop any growth-stimulating mechanism. Here, the non–small cell lung cancer (NSCLC) PC9 cell line was used to systematically profile, by mass spectrometry, changes in the proteome, kinome, and phosphoproteome during early treatment with the EGFR inhibitor afatinib. Regardless of the response, initial drug-sensitive cells rapidly adapt to targeted therapy, and within days, cells regained the capacity to proliferate, despite persisting target inhibition. These data reveal a rapid reactivation of mTOR and MAPK signaling pathways after initial inhibition and an increase in abundance and activity of cytoskeleton and calcium signaling–related proteins. Pharmacologic inhibition of reactivated pathways resulted in increased afatinib efficacy. However more strikingly, cells that were restricted from accessing extracellular calcium were extremely sensitive to afatinib treatment. These findings were validated using three additional inhibitors tested in four different NSCLC cell lines, and the data clearly indicated a role for Ca2+ signaling during the development of adaptive resistance. From a therapeutic point of view, the increased inhibitor efficacy could limit or even prevent further resistance development.

Implications: Combined targeting of calcium signaling and RTKs may limit drug resistance and improve treatment efficacy. Mol Cancer Res; 16(11); 1773–84. ©2018 AACR.
Data from AHNAK Loss in Mice Promotes Type II Pneumocyte Hyperplasia and Lung Tumor Development
Authors: Park Jun Won , Kim Il Yong , Choi Ji Won , Lim Hee Jung , Shin Jae Hoon , Kim Yo Na , Lee Seo Hyun , Son Yeri , Sohn Mira , Woo Jong Kyu , Jeong Joseph H. , Lee Cheolju , Bae Yun Soo , Seong Je Kyung
Published: March 2024

Abstract
AHNAK is known to be a tumor suppressor in breast cancer due to its ability to activate the TGFβ signaling pathway. However, the role of AHNAK in lung tumor development and progression remains unknown. Here, the Ahnak gene was disrupted to determine its effect on lung tumorigenesis and the mechanism by which it triggers lung tumor development was investigated. First, AHNAK protein expression was determined to be decreased in human lung adenocarcinomas compared with matched nonneoplastic lung tissues. Then, Ahnak−/− mice were used to investigate the role of AHNAK in pulmonary tumorigenesis. Ahnak−/− mice showed increased lung volume and thicker alveolar walls with type II pneumocyte hyperplasia. Most importantly, approximately 20% of aged Ahnak−/− mice developed lung tumors, and Ahnak−/− mice were more susceptible to urethane-induced pulmonary carcinogenesis than wild-type mice. Mechanistically, Ahnak deficiency promotes the cell growth of lung epithelial cells by suppressing the TGFβ signaling pathway. In addition, increased numbers of M2-like alveolar macrophages (AM) were observed in Ahnak−/− lungs, and the depletion of AMs in Ahnak−/− lungs alleviated lung hyperplastic lesions, suggesting that M2-like AMs promoted the progression of lung hyperplastic lesions in Ahnak-null mice. Collectively, AHNAK suppresses type II pneumocyte proliferation and inhibits tumor-promoting M2 alternative activation of macrophages in mouse lung tissue. These results suggest that AHNAK functions as a novel tumor suppressor in lung cancer.

Implications: The tumor suppressor function of AHNAK, in murine lungs, occurs by suppressing alveolar epithelial cell proliferation and modulating lung microenvironment. Mol Cancer Res; 16(8); 1287–98. ©2018 AACR.
Data from E-Cadherin Represses Anchorage-Independent Growth in Sarcomas through Both Signaling and Mechanical Mechanisms
Authors: Jolly Mohit Kumar , Ware Kathryn E. , Xu Shengnan , Gilja Shivee , Shetler Samantha , Yang Yanjun , Wang Xueyang , Austin R. Garland , Runyambo Daniella , Hish Alexander J. , Bartholf DeWitt Suzanne , George Jason T. , Kreulen R. Timothy , Boss Mary-Keara , Lazarides Alexander L. , Kerr David L. , Gerber Drew G. , Sivaraj Dharshan , Armstrong Andrew J. , Dewhirst Mark W. , Eward William C. , Levine Herbert , Somarelli Jason A.
Published: March 2024

Abstract
CDH1 (also known as E-cadherin), an epithelial-specific cell–cell adhesion molecule, plays multiple roles in maintaining adherens junctions, regulating migration and invasion, and mediating intracellular signaling. Downregulation of E-cadherin is a hallmark of epithelial-to-mesenchymal transition (EMT) and correlates with poor prognosis in multiple carcinomas. Conversely, upregulation of E-cadherin is prognostic for improved survival in sarcomas. Yet, despite the prognostic benefit of E-cadherin expression in sarcoma, the mechanistic significance of E-cadherin in sarcomas remains poorly understood. Here, by combining mathematical models with wet-bench experiments, we identify the core regulatory networks mediated by E-cadherin in sarcomas, and decipher their functional consequences. Unlike carcinomas, E-cadherin overexpression in sarcomas does not induce a mesenchymal-to-epithelial transition (MET). However, E-cadherin acts to reduce both anchorage-independent growth and spheroid formation of sarcoma cells. Ectopic E-cadherin expression acts to downregulate phosphorylated CREB1 (p-CREB) and the transcription factor, TBX2, to inhibit anchorage-independent growth. RNAi-mediated knockdown of TBX2 phenocopies the effect of E-cadherin on CREB levels and restores sensitivity to anchorage-independent growth in sarcoma cells. Beyond its signaling role, E-cadherin expression in sarcoma cells can also strengthen cell–cell adhesion and restricts spheroid growth through mechanical action. Together, our results demonstrate that E-cadherin inhibits sarcoma aggressiveness by preventing anchorage-independent growth.
Implications:
We highlight how E-cadherin can restrict aggressive behavior in sarcomas through both biochemical signaling and biomechanical effects.
Data from Activation of Epidermal Growth Factor Receptor and Its Downstream Signaling Pathway by Nitric Oxide in Response to Ionizing Radiation
Authors: Lee Hyung-Chahn , An Sungkwan , Lee Hansoo , Woo Sang-Hyeok , Jin Hyeon-Ok , Seo Sung-Keum , Choe Tae-Boo , Yoo Doo-Hyun , Lee Su-Jae , Hong Young-Joon , Park Myung-Jin , Rhee Chang-Hun , Park In-Chul , Hong Seok-Il
Published: March 2024

Abstract
Epidermal growth factor receptor (EGFR) is activated by ionizing radiation (IR), but the molecular mechanism for this effect is unknown. We have found that intracellular generation of nitric oxide (NO) by NO synthase (NOS) is required for the rapid activation of EGFR phosphorylation by IR. Treatment of A549 lung cancer cells with IR increased NOS activity within minutes, accompanied by an increase of NO. 2-Phenyl-4,4,5,5,-tetramethylimidazolline-1-oxyl-3-oxide, an NO scavenger, and NG-monomethyl-l-arginine, an NOS inhibitor, abolished the increase in intracellular NO and activation of EGFR by IR. In addition, an NO donor alone induced EGFR phosphorylation. Transient transfection with small interfering RNA for endothelial NOS reduced IR-induced NO production and suppressed IR-induced EGFR activation. Overexpression of endothelial NOS increased IR-induced NO generation and EGFR activation. These results indicate a novel molecular mechanism for EGFR activation by IR-induced NO production via NOS. (Mol Cancer Res 2008;6(6):996–1002)
Data from Alpha-Melanocyte–Stimulating Hormone Suppresses Oxidative Stress through a p53-Mediated Signaling Pathway in Human Melanocytes
Authors: Kadekaro Ana Luisa , Chen Juping , Yang Jennifer , Chen Shuna , Jameson Joshua , Swope Viki B. , Cheng Tan , Kadakia Madhavi , Abdel-Malek Zalfa
Published: March 2024

Abstract
Epidermal melanocytes are skin cells specialized in melanin production. Activation of the melanocortin 1 receptor (MC1R) on melanocytes by α-melanocyte–stimulating hormone (α-MSH) induces synthesis of the brown/black pigment eumelanin that confers photoprotection from solar UV radiation (UVR). Contrary to keratinocytes, melanocytes are slow proliferating cells that persist in the skin for decades, in an environment with high levels of UVR-induced reactive oxygen species (ROS). We previously reported that in addition to its role in pigmentation, α-MSH also reduces oxidative stress and enhances the repair of DNA photoproducts in melanocytes, independent of melanin synthesis. Given the significance of ROS in carcinogenesis, here we investigated the mechanisms by which α-MSH exerts antioxidant effects in melanocytes. We show that activation of the MC1R by α-MSH contributes to phosphorylation of p53 on serine 15, a known requirement for stabilization and activation of p53, a major sensor of DNA damage. This effect is mediated by the cAMP/PKA pathway and by the activation of phosphoinositide 3-kinase (PI3K) ATR and DNA protein kinase (DNA-PK). α-MSH increases the levels of 8-oxoguanine DNA glycosylase (OGG1) and apurinic apyrimidinic endonuclease 1 (APE-1/Ref-1), enzymes essential for base excision repair. Nutlin-3, an HDM2 inhibitor, mimicked the effects of α-MSH resulting in reduced phosphorylation of H2AX (γ-H2AX), a marker of DNA damage. Conversely, the p53 inhibitor pifithrin-α or silencing of p53 abolished the effects of α-MSH and augmented oxidative stress. These results show that p53 is an important target of the downstream MC1R signaling that reduces oxidative stress and possibly malignant transformation of melanocytes. Mol Cancer Res; 10(6); 778–86. ©2012 AACR.
Data from MicroRNAs Associated with Mitogen-Activated Protein Kinase in Human Pancreatic Cancer
Authors: Ikeda Yushi , Tanji Etsuko , Makino Naohiko , Kawata Sumio , Furukawa Toru
Published: March 2024

Abstract
Aberrant expression of microRNAs (miRNA) is associated with phenotypes of various cancers, including pancreatic cancer. However, the mechanism of the aberrant expression is largely unknown. Activation of the mitogen-activated protein kinase (MAPK) signaling pathway plays a crucial role in gene expression related to the malignant phenotype of pancreatic cancer. Hence, we studied the role of MAPK in the aberrant expression of miRNAs in pancreatic cancer cells. The alterations in expression of 183 miRNAs induced by activation or inactivation of MAPK were assayed in cultured pancreatic cancer cells and HEK293 cells by means of the quantitative real-time PCR method. We found that four miRNAs, namely, miR-7-3, miR-34a, miR-181d, and miR-193b, were preferentially associated with MAPK activity. Among these miRNAs, miR-7-3 was upregulated by active MAPK, whereas the others were downregulated. Promoter assays indicated that the promoter activities of the host genes of miR-7-3 and miR-34a were both downregulated by alteration in MAPK activity. Exogenous overexpression of the MAPK-associated miRNAs had the effect of inhibition of the proliferation of cultured pancreatic cancer cells; miR-193b was found to exhibit the most remarkable inhibition. A search for target genes of miR-193b led to identification of CCND1, NT5E, PLAU, STARD7, STMN1, and YWHAZ as the targets. Translational suppression of these genes by miR-193b was confirmed by reporter assay. These results indicate that activation of MAPK may play a significant role in aberrant expression of miRNAs and their associated phenotypes in pancreatic cancer. Mol Cancer Res; 10(2); 259–69. ©2011 AACR.
Data from Metastasis-Specific Gene Expression in Autochthonous and Allograft Mouse Mammary Tumor Models: Stratification and Identification of Targetable Signatures
Authors: Ross Christina , Szczepanek Karol , Lee Maxwell , Yang Howard , Peer Cody J. , Kindrick Jessica , Shankarappa Priya , Lin Zhi-Wei , Sanford Jack D. , Figg William D. , Hunter Kent W.
Published: March 2024

Abstract
Breast cancer metastasis is a leading cause of cancer-related death of women in the United States. A hurdle in advancing metastasis-targeted intervention is the phenotypic heterogeneity between primary and secondary lesions. To identify metastasis-specific gene expression profiles we performed RNA-sequencing of breast cancer mouse models; analyzing metastases from models of various drivers and routes. We contrasted the models and identified common, targetable signatures. Allograft models exhibited more mesenchymal-like gene expression than genetically engineered mouse models (GEMM), and primary culturing of GEMM-derived metastatic tissue induced mesenchymal-like gene expression. In addition, metastasis-specific transcriptomes differed between tail vein and orthotopic injection of the same cell line. Gene expression common to models of spontaneous metastasis included sildenafil response and nicotine degradation pathways. Strikingly, in vivo sildenafil treatment significantly reduced metastasis by 54%, while nicotine significantly increased metastasis by 46%. These data suggest that (i) actionable metastasis-specific pathways can be readily identified, (ii) already available drugs may have great potential to alleviate metastatic incidence, and (iii) metastasis may be influenced greatly by lifestyle choices such as the choice to consume nicotine products. In summary, while mouse models of breast cancer metastasis vary in ways that must not be ignored, there are shared features that can be identified and potentially targeted therapeutically.
Implications:
The data we present here exposes critical variances between preclinical models of metastatic breast cancer and identifies targetable pathways integral to metastatic spread.
Visual Overview:
http://mcr.aacrjournals.org/content/molcanres/18/9/1278/F1.large.jpg.
Data from Disseminated Prostate Cancer Cells Can Instruct Hematopoietic Stem and Progenitor Cells to Regulate Bone Phenotype
Authors: Joseph Jeena , Shiozawa Yusuke , Jung Younghun , Kim Jin Koo , Pedersen Elisabeth , Mishra Anjali , Zalucha Janet Linn , Wang Jingcheng , Keller Evan T. , Pienta Kenneth J. , Taichman Russell S.
Published: March 2024

Abstract
Prostate cancer metastases and hematopoietic stem cells (HSC) frequently home to the bone marrow, where they compete to occupy the same HSC niche. We have also shown that under conditions of hematopoietic stress, HSCs secrete the bone morphogenetic proteins (BMP)-2 and BMP-6 that drives osteoblastic differentiation from mesenchymal precursors. As it is not known, we examined whether metastatic prostate cancer cells can alter regulation of normal bone formation by HSCs and hematopoietic progenitor cells (HPC). HSC/HPCs isolated from mice bearing nonmetastatic and metastatic tumor cells were isolated and their ability to influence osteoblastic and osteoclastic differentiation was evaluated. When the animals were inoculated with the LNCaP C4-2B cell line, which produces mixed osteoblastic and osteolytic lesions in bone, HPCs, but not HSCs, were able to induced stromal cells to differentiate down an osteoblastic phenotype. Part of the mechanism responsible for this activity was the production of BMP-2. On the other hand, when the animals were implanted with PC3 cells that exhibits predominantly osteolytic lesions in bone, HSCs derived from these animals were capable of directly differentiating into tartrate-resistant acid phosphatase–positive osteoclasts through an interleukin-6–mediated pathway. These studies for the first time identify HSC/HPCs as novel targets for future therapy involved in the bone abnormalities of prostate cancer. Mol Cancer Res; 10(3); 282–92. ©2012 AACR.