bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from The EMT Transcription Factor ZEB2 Promotes Proliferation of Primary and Metastatic Melanoma While Suppressing an Invasive, Mesenchymal-Like Phenotype
Authors: Vandamme Niels , Denecker Geertrui , Bruneel Kenneth , Blancke Gillian , Akay Özden , Taminau Joachim , De Coninck Jordy , De Smedt Eva , Skrypek Nicolas , Van Loocke Wouter , Wouters Jasper , Nittner David , Köhler Corinna , Darling Douglas S. , Cheng Phil F. , Raaijmakers Marieke I.G. , Levesque Mitchell P. , Mallya Udupi Girish , Rafferty Mairin , Balint Balazs , Gallagher William M. , Brochez Lieve , Huylebroeck Danny , Haigh Jody J. , Andries Vanessa , Rambow Florian , Van Vlierberghe Pieter , Goossens Steven , van den Oord Joost J. , Marine Jean-Christophe , Berx Geert
Published: March 2023

Abstract
Epithelial-to-mesenchymal transition (EMT)-inducing transcription factors (TF) are well known for their ability to induce mesenchymal states associated with increased migratory and invasive properties. Unexpectedly, nuclear expression of the EMT-TF ZEB2 in human primary melanoma has been shown to correlate with reduced invasion. We report here that ZEB2 is required for outgrowth for primary melanomas and metastases at secondary sites. Ablation of Zeb2 hampered outgrowth of primary melanomas in vivo, whereas ectopic expression enhanced proliferation and growth at both primary and secondary sites. Gain of Zeb2 expression in pulmonary-residing melanoma cells promoted the development of macroscopic lesions. In vivo fate mapping made clear that melanoma cells undergo a conversion in state where ZEB2 expression is replaced by ZEB1 expression associated with gain of an invasive phenotype. These findings suggest that reversible switching of the ZEB2/ZEB1 ratio enhances melanoma metastatic dissemination.
Significance:
ZEB2 function exerts opposing behaviors in melanoma by promoting proliferation and expansion and conversely inhibiting invasiveness, which could be of future clinical relevance.
Data from USP10 Promotes Proliferation of Hepatocellular Carcinoma by Deubiquitinating and Stabilizing YAP/TAZ
Authors: Zhu Hong , Yan Fangjie , Yuan Tao , Qian Meijia , Zhou Tianyi , Dai Xiaoyang , Cao Ji , Ying Meidan , Dong Xiaowu , He Qiaojun , Yang Bo
Published: March 2023

Abstract
Yes-associated protein (YAP) and its paralog, transcriptional coactivator with PDZ-binding motif (TAZ), play pivotal roles in promoting the progression of hepatocellular carcinoma. However, the regulatory mechanism underpinning aberrant activation of YAP/TAZ in hepatocellular carcinoma remains unclear. In this study, we globally profiled the contribution of deubiquitinating enzymes (DUB) to both transcriptional activity and protein abundance of YAP/TAZ in hepatocellular carcinoma models and identified ubiquitin-specific peptidase 10 (USP10) as a potent YAP/TAZ-activating DUB. Mechanistically, USP10 directly interacted with and stabilized YAP/TAZ by reverting their proteolytic ubiquitination. Depletion of USP10 enhanced polyubiquitination of YAP/TAZ, promoted their proteasomal degradation, and ultimately arrested the proliferation of hepatocellular carcinoma in vitro and in vivo. Expression levels of USP10 positively correlated with the abundance of YAP/TAZ in hepatocellular carcinoma patient samples as well as in N-nitrosodiethylamine (DEN)-induced liver cancer mice models. Collectively, this study establishes the causal link between USP10 and hyperactivated YAP/TAZ in hepatocellular carcinoma cells and provides a rationale for potential therapeutic interventions in the treatment of patients with hepatocellular carcinoma harboring a high level of YAP/TAZ.
Significance:
These findings identify USP10 as a DUB of YAP/TAZ and its role in hepatocellular carcinoma progression, which may serve as a potential therapeutic target for hepatocellular carcinoma treatment.
Data from Epigenetic Regulation of the PTEN–AKT–RAC1 Axis by G9a Is Critical for Tumor Growth in Alveolar Rhabdomyosarcoma
Authors: Bhat Akshay V. , Palanichamy Kala Monica , Rao Vinay Kumar , Pignata Luca , Lim Huey Jin , Suriyamurthy Sudha , Chang Kenneth T. , Lee Victor K. , Guccione Ernesto , Taneja Reshma
Published: March 2023

Abstract
Alveolar rhabdomyosarcoma (ARMS) is an aggressive pediatric cancer with poor prognosis. As transient and stable modifications to chromatin have emerged as critical mechanisms in oncogenic signaling, efforts to target epigenetic modifiers as a therapeutic strategy have accelerated in recent years. To identify chromatin modifiers that sustain tumor growth, we performed an epigenetic screen and found that inhibition of lysine methyltransferase G9a significantly affected the viability of ARMS cell lines. Targeting expression or activity of G9a reduced cellular proliferation and motility in vitro and tumor growth in vivo. Transcriptome and chromatin immunoprecipitation–sequencing analysis provided mechanistic evidence that the tumor-suppressor PTEN was a direct target gene of G9a. G9a repressed PTEN expression in a methyltransferase activity–dependent manner, resulting in increased AKT and RAC1 activity. Re-expression of constitutively active RAC1 in G9a-deficient tumor cells restored oncogenic phenotypes, demonstrating its critical functions downstream of G9a. Collectively, our study provides evidence for a G9a-dependent epigenetic program that regulates tumor growth and suggests targeting G9a as a therapeutic strategy in ARMS.
Significance:
These findings demonstrate that RAC1 is an effector of G9a oncogenic functions and highlight the potential of G9a inhibitors in the treatment of ARMS.
Data from An Interactive Resource to Probe Genetic Diversity and Estimated Ancestry in Cancer Cell Lines
Authors: Dutil Julie , Chen Zhihua , Monteiro Alvaro N. , Teer Jamie K. , Eschrich Steven A.
Published: March 2023

Abstract
Recent work points to a lack of diversity in genomics studies from genome-wide association studies to somatic (tumor) genome analyses. Yet, population-specific genetic variation has been shown to contribute to health disparities in cancer risk and outcomes. Immortalized cancer cell lines are widely used in cancer research, from mechanistic studies to drug screening. Larger collections of cancer cell lines better represent the genomic heterogeneity found in primary tumors. Yet, the genetic ancestral origin of cancer cell lines is rarely acknowledged and often unknown. Using genome-wide genotyping data from 1,393 cancer cell lines from the Catalogue of Somatic Mutations in Cancer (COSMIC) and Cancer Cell Line Encyclopedia (CCLE), we estimated the genetic ancestral origin for each cell line. Our data indicate that cancer cell line collections are not representative of the diverse ancestry and admixture characterizing human populations. We discuss the implications of genetic ancestry and diversity of cellular models for cancer research and present an interactive tool, Estimated Cell Line Ancestry (ECLA), where ancestry can be visualized with reference populations of the 1000 Genomes Project. Cancer researchers can use this resource to identify cell line models for their studies by taking ancestral origins into consideration.
Data from An Orally Active Galectin-3 Antagonist Inhibits Lung Adenocarcinoma Growth and Augments Response to PD-L1 Blockade
Authors: Vuong Lynda , Kouverianou Eleni , Rooney Claire M. , McHugh Brian J. , Howie Sarah E.M. , Gregory Christopher D. , Forbes Stuart J. , Henderson Neil C. , Zetterberg Fredrik R. , Nilsson Ulf J. , Leffler Hakon , Ford Paul , Pedersen Anders , Gravelle Lise , Tantawi Susan , Schambye Hans , Sethi Tariq , MacKinnon Alison C.
Published: March 2023

Abstract
A combination therapy approach is required to improve tumor immune infiltration and patient response to immune checkpoint inhibitors that target negative regulatory receptors. Galectin-3 is a β-galactoside-binding lectin that is highly expressed within the tumor microenvironment of aggressive cancers and whose expression correlates with poor survival particularly in patients with non–small cell lung cancer (NSCLC). To examine the role of galectin-3 inhibition in NSCLC, we tested the effects of galectin-3 depletion using genetic and pharmacologic approaches on syngeneic mouse lung adenocarcinoma and human lung adenocarcinoma xenografts. Galectin-3−/− mice developed significantly smaller and fewer tumors and metastases than syngeneic C57/Bl6 wild-type mice. Macrophage ablation retarded tumor growth, whereas reconstitution with galectin-3-positive bone marrow restored tumor growth in galectin-3−/− mice, indicating that macrophages were a major driver of the antitumor response. Oral administration of a novel small molecule galectin-3 inhibitor GB1107 reduced human and mouse lung adenocarcinoma growth and blocked metastasis in the syngeneic model. Treatment with GB1107 increased tumor M1 macrophage polarization and CD8+ T-cell infiltration. Moreover, GB1107 potentiated the effects of a PD-L1 immune checkpoint inhibitor to increase expression of cytotoxic (IFNγ, granzyme B, perforin-1, Fas ligand) and apoptotic (cleaved caspase-3) effector molecules. In summary, galectin-3 is an important regulator of lung adenocarcinoma progression. The novel galectin-3 inhibitor presented could provide an effective, nontoxic monotherapy or be used in combination with immune checkpoint inhibitors to boost immune infiltration and responses in lung adenocarcinoma and potentially other aggressive cancers.
Significance:
A novel and orally active galectin-3 antagonist inhibits lung adenocarcinoma growth and metastasis and augments response to PD-L1 blockade.
Data from Extracellular Vesicles from Cancer-Associated Fibroblasts Containing Annexin A6 Induces FAK-YAP Activation by Stabilizing β1 Integrin, Enhancing Drug Resistance
Authors: Uchihara Tomoyuki , Miyake Keisuke , Yonemura Atsuko , Komohara Yoshihiro , Itoyama Rumi , Koiwa Mayu , Yasuda Tadahito , Arima Kota , Harada Kazuto , Eto Kojiro , Hayashi Hiromitsu , Iwatsuki Masaaki , Iwagami Shiro , Baba Yoshifumi , Yoshida Naoya , Yashiro Masakazu , Masuda Mari , Ajani Jaffer A. , Tan Patrick , Baba Hideo , Ishimoto Takatsugu
Published: March 2023

Abstract
Extracellular vesicles (EV) from cancer-associated fibroblasts (CAF) are composed of diverse payloads. Although CAFs impact the aggressive characteristics of gastric cancer cells, the contribution of CAF-EV to gastric cancer progression has not been elucidated. Here, we investigated the molecular mechanism of the changes in gastric cancer characteristics induced by CAF-EV. CAF abundance in gastric cancer tissues was associated with poor prognosis of patients with gastric cancer receiving chemotherapy. Moreover, CAF-EV induced tubular network formation and drug resistance of gastric cancer cells in the extracellular matrix (ECM). Comprehensive proteomic analysis of CAF-EV identified that Annexin A6 plays a pivotal role in network formation and drug resistance of gastric cancer cells in the ECM via activation of β1 integrin-focal adhesion kinase (FAK)-YAP. A peritoneal metastasis mouse model revealed that CAF-EV induced drug resistance in peritoneal tumors, and inhibition of FAK or YAP efficiently attenuated gastric cancer drug resistance in vitro and in vivo. These findings demonstrate that drug resistance is conferred by Annexin A6 in CAF-EV and provide a potential avenue for overcoming gastric cancer drug resistance through the inhibition of FAK-YAP signaling in combination with conventional chemotherapeutics.
Significance:
This study elucidates a novel molecular mechanism through which Annexin A6 in CAF-EV activates FAK-YAP by stabilizing β1 integrin at the cell surface of gastric cancer cells and subsequently induces drug resistance.
Data from Brain Tumor Stem Cell Dependence on Glutaminase Reveals a Metabolic Vulnerability through the Amino Acid Deprivation Response Pathway
Authors: Restall Ian J. , Cseh Orsolya , Richards Laura M. , Pugh Trevor J. , Luchman H. Artee , Weiss Samuel
Published: March 2023

Abstract
Cancer cells can metabolize glutamine to replenish TCA cycle intermediates, leading to a dependence on glutaminolysis for cell survival. However, a mechanistic understanding of the role that glutamine metabolism has on the survival of glioblastoma (GBM) brain tumor stem cells (BTSC) has not yet been elucidated. Here, we report that across a panel of 19 GBM BTSC lines, inhibition of glutaminase (GLS) showed a variable response from complete blockade of cell growth to absolute resistance. Surprisingly, BTSC sensitivity to GLS inhibition was a result of reduced intracellular glutamate triggering the amino acid deprivation response (AADR) and not due to the contribution of glutaminolysis to the TCA cycle. Moreover, BTSC sensitivity to GLS inhibition negatively correlated with expression of the astrocytic glutamate transporters EAAT1 and EAAT2. Blocking glutamate transport in BTSCs with high EAAT1/EAAT2 expression rendered cells susceptible to GLS inhibition, triggering the AADR and limiting cell growth. These findings uncover a unique metabolic vulnerability in BTSCs and support the therapeutic targeting of upstream activators and downstream effectors of the AADR pathway in GBM. Moreover, they demonstrate that gene expression patterns reflecting the cellular hierarchy of the tissue of origin can alter the metabolic requirements of the cancer stem cell population.
Significance:
Glioblastoma brain tumor stem cells with low astrocytic glutamate transporter expression are dependent on GLS to maintain intracellular glutamate to prevent the amino acid deprivation response and cell death.
Data from A Versatile ES Cell–Based Melanoma Mouse Modeling Platform
Authors: Bok Ilah , Vera Olga , Xu Xiaonan , Jasani Neel , Nakamura Koji , Reff Jordan , Nenci Arianna , Gonzalez Jose G. , Karreth Florian A.
Published: March 2023

Abstract
The cumbersome and time-consuming process of generating new mouse strains and multiallelic experimental animals often hinders the use of genetically engineered mouse models (GEMM) in cancer research. Here, we describe the development and validation of an embryonic stem cell (ESC)-GEMM platform for rapid modeling of melanoma in mice. The platform incorporates 12 clinically relevant genotypes composed of combinations of four driver alleles (LSL-BrafV600E, LSL-NrasQ61R, PtenFlox, and Cdkn2aFlox) and regulatory alleles to spatiotemporally control the perturbation of genes of interest. The ESCs produce high-contribution chimeras, which recapitulate the melanoma phenotypes of conventionally bred mice. Using the ESC-GEMM platform to modulate Pten expression in melanocytes in vivo, we highlighted the utility and advantages of gene depletion by CRISPR-Cas9, RNAi, or conditional knockout for melanoma modeling. Moreover, complementary genetic methods demonstrated the impact of Pten restoration on the prevention and maintenance of Pten-deficient melanomas. Finally, we showed that chimera-derived melanoma cell lines retain regulatory allele competency and are a powerful resource to complement ESC-GEMM chimera experiments in vitro and in syngeneic grafts in vivo. Thus, when combined with sophisticated genetic tools, the ESC-GEMM platform enables rapid, high-throughput, and versatile studies aimed at addressing outstanding questions in melanoma biology.

Significance: This study presents a high-throughput and versatile ES cell-based mouse modeling platform that can be combined with state-of-the-art genetic tools to address unanswered questions in melanoma in vivo.

See related commentary by Thorkelsson et al., p. 655
Data from HDAC6 Plays a Noncanonical Role in the Regulation of Antitumor Immune Responses, Dissemination, and Invasiveness of Breast Cancer
Authors: Banik Debarati , Noonepalle Satish , Hadley Melissa , Palmer Erica , Gracia-Hernandez Maria , Zevallos-Delgado Christian , Manhas Namratta , Simonyan Hayk , Young Colin N. , Popratiloff Anastas , Chiappinelli Katherine B. , Fernandes Rohan , Sotomayor Eduardo M. , Villagra Alejandro
Published: March 2023

Abstract
Despite the outstanding clinical results of immune checkpoint blockade (ICB) in melanoma and other cancers, clinical trials in breast cancer have reported low responses to these therapies. Current efforts are now focused on improving the treatment efficacy of ICB in breast cancer using new combination designs such as molecularly targeted agents, including histone deacetylase inhibitors (HDACi). These epigenetic drugs have been widely described as potent cytotoxic agents for cancer cells. In this work, we report new noncanonical regulatory properties of ultra-selective HDAC6i over the expression and function of epithelial–mesenchymal transition pathways and the invasiveness potential of breast cancer. These unexplored roles position HDAC6i as attractive options to potentiate ongoing immunotherapeutic approaches. These new functional activities of HDAC6i involved regulation of the E-cadherin/STAT3 axis. Pretreatment of tumors with HDAC6i induced critical changes in the tumor microenvironment, resulting in improved effectiveness of ICB and preventing dissemination of cancer cells to secondary niches. Our results demonstrate for the first time that HDAC6i can both improve ICB antitumor immune responses and diminish the invasiveness of breast cancer with minimal cytotoxic effects, thus departing from the cytotoxicity-centric paradigm previously assigned to HDACi.
Significance:
Ultraselective HDAC6 inhibitors can reduce tumor growth and invasiveness of breast cancer by noncanonical mechanisms unrelated to the previously cytotoxic properties attributed to HDAC inhibitors.
Data from Pyrvinium Pamoate Induces Death of Triple-Negative Breast Cancer Stem–Like Cells and Reduces Metastases through Effects on Lipid Anabolism
Authors: Dattilo Rosanna , Mottini Carla , Camera Emanuela , Lamolinara Alessia , Auslander Noam , Doglioni Ginevra , Muscolini Michela , Tang Wei , Planque Melanie , Ercolani Cristiana , Buglioni Simonetta , Manni Isabella , Trisciuoglio Daniela , Boe Alessandra , Grande Sveva , Luciani Anna Maria , Iezzi Manuela , Ciliberto Gennaro , Ambs Stefan , De Maria Ruggero , Fendt Sarah-Maria , Ruppin Eytan , Cardone Luca
Published: March 2023

Abstract
Cancer stem-like cells (CSC) induce aggressive tumor phenotypes such as metastasis formation, which is associated with poor prognosis in triple-negative breast cancer (TNBC). Repurposing of FDA-approved drugs that can eradicate the CSC subcompartment in primary tumors may prevent metastatic disease, thus representing an effective strategy to improve the prognosis of TNBC. Here, we investigated spheroid-forming cells in a metastatic TNBC model. This strategy enabled us to specifically study a population of long-lived tumor cells enriched in CSCs, which show stem-like characteristics and induce metastases. To repurpose FDA-approved drugs potentially toxic for CSCs, we focused on pyrvinium pamoate (PP), an anthelmintic drug with documented anticancer activity in preclinical models. PP induced cytotoxic effects in CSCs and prevented metastasis formation. Mechanistically, the cell killing effects of PP were a result of inhibition of lipid anabolism and, more specifically, the impairment of anabolic flux from glucose to cholesterol and fatty acids. CSCs were strongly dependent upon activation of lipid biosynthetic pathways; activation of these pathways exhibited an unfavorable prognostic value in a cohort of breast cancer patients, where it predicted high probability of metastatic dissemination and tumor relapse. Overall, this work describes a new approach to target aggressive CSCs that may substantially improve clinical outcomes for patients with TNBC, who currently lack effective targeted therapeutic options.
Significance:
These findings provide preclinical evidence that a drug repurposing approach to prevent metastatic disease in TNBC exploits lipid anabolism as a metabolic vulnerability against CSCs in primary tumors.
Data from iNOS Regulates the Therapeutic Response of Pancreatic Cancer Cells to Radiotherapy
Authors: Pereira Patricia M.R. , Edwards Kimberly J. , Mandleywala Komal , Carter Lukas M. , Escorcia Freddy E. , Campesato Luis Felipe , Cornejo Mike , Abma Lolkje , Mohsen Abu-Akeel , Iacobuzio-Donahue Christine A. , Merghoub Taha , Lewis Jason S.
Published: March 2023

Abstract
Pancreatic ductal adenocarcinoma (PDAC) is highly resistant to radiotherapy, chemotherapy, or a combination of these modalities, and surgery remains the only curative intervention for localized disease. Although cancer-associated fibroblasts (CAF) are abundant in PDAC tumors, the effects of radiotherapy on CAFs and the response of PDAC cells to radiotherapy are unknown. Using patient samples and orthotopic PDAC biological models, we showed that radiotherapy increased inducible nitric oxide synthase (iNOS) in the tumor tissues. Mechanistic in vitro studies showed that, although undetectable in radiotherapy-activated tumor cells, iNOS expression and nitric oxide (NO) secretion were significantly increased in CAFs secretome following radiotherapy. Culture of PDAC cells with conditioned media from radiotherapy-activated CAFs increased iNOS/NO signaling in tumor cells through NF-κB, which, in turn, elevated the release of inflammatory cytokines by the tumor cells. Increased NO after radiotherapy in PDAC contributed to an acidic microenvironment that was detectable using the radiolabeled pH (low) insertion peptide (pHLIP). In murine orthotopic PDAC models, pancreatic tumor growth was delayed when iNOS inhibition was combined with radiotherapy. These data show the important role that iNOS/NO signaling plays in the effectiveness of radiotherapy to treat PDAC tumors.
Significance:
A radiolabeled pH-targeted peptide can be used as a PET imaging tool to assess therapy response within PDAC and blocking iNOS/NO signaling may improve radiotherapy outcomes.
Data from A Sox2:miR-486-5p Axis Regulates Survival of GBM Cells by Inhibiting Tumor Suppressor Networks
Authors: Lopez-Bertoni Hernando , Kotchetkov Ivan S. , Mihelson Nicole , Lal Bachchu , Rui Yuan , Ames Heather , Lugo-Fagundo Maria , Guerrero-Cazares Hugo , Quiñones-Hinojosa Alfredo , Green Jordan J. , Laterra John
Published: March 2023

Abstract
Glioblastoma multiforme (GBM) and other solid malignancies are heterogeneous and contain subpopulations of tumor cells that exhibit stem-like features. Our recent findings point to a dedifferentiation mechanism by which reprogramming transcription factors Oct4 and Sox2 drive the stem-like phenotype in glioblastoma, in part, by differentially regulating subsets of miRNAs. Currently, the molecular mechanisms by which reprogramming transcription factors and miRNAs coordinate cancer stem cell tumor-propagating capacity are unclear. In this study, we identified miR-486-5p as a Sox2-induced miRNA that targets the tumor suppressor genes PTEN and FoxO1 and regulates the GBM stem-like cells. miR-486-5p associated with the GBM stem cell phenotype and Sox2 expression and was directly induced by Sox2 in glioma cell lines and patient-derived neurospheres. Forced expression of miR-486-5p enhanced the self-renewal capacity of GBM neurospheres, and inhibition of endogenous miR-486-5p activated PTEN and FoxO1 and induced cell death by upregulating proapoptotic protein BIM via a PTEN-dependent mechanism. Furthermore, delivery of miR-486-5p antagomirs to preestablished orthotopic GBM neurosphere-derived xenografts using advanced nanoparticle formulations reduced tumor sizes in vivo and enhanced the cytotoxic response to ionizing radiation. These results define a previously unrecognized and therapeutically targetable Sox2:miR-486-5p axis that enhances the survival of GBM stem cells by repressing tumor suppressor pathways.
Significance:
This study identifies a novel axis that links core transcriptional drivers of cancer cell stemness to miR-486-5p–dependent modulation of tumor suppressor genes that feeds back to regulate glioma stem cell survival.
Data from Targeting p63 Upregulation Abrogates Resistance to MAPK Inhibitors in Melanoma
Authors: Patel Ankit , Garcia Lucia Fraile , Mannella Viviana , Gammon Luke , Borg Tiffanie-Marie , Maffucci Tania , Scatolini Maria , Chiorino Giovanna , Vergani Elisabetta , Rodolfo Monica , Maurichi Andrea , Posch Christian , Matin Rubeta N. , Harwood Catherine A. , Bergamaschi Daniele
Published: March 2023

Abstract
Targeting the MAPK pathway by combined inhibition of BRAF and MEK has increased overall survival in advanced BRAF-mutant melanoma in both therapeutic and adjuvant clinical settings. However, a significant proportion of tumors develop acquired resistance, leading to treatment failure. We have previously shown p63 to be an important inhibitor of p53-induced apoptosis in melanoma following genotoxic drug exposure. Here, we investigated the role of p63 in acquired resistance to MAPK inhibition and show that p63 isoforms are upregulated in melanoma cell lines chronically exposed to BRAF and MEK inhibition, with consequent increased resistance to apoptosis. This p63 upregulation was the result of its reduced degradation by the E3 ubiquitin ligase FBXW7. FBXW7 was itself regulated by MDM2, and in therapy-resistant melanoma cell lines, nuclear accumulation of MDM2 caused downregulation of FBXW7 and consequent upregulation of p63. Consistent with this, both FBXW7-inactivating mutations and MDM2 upregulation were found in melanoma clinical samples. Treatment of MAPK inhibitor–resistant melanoma cells with MDM2 inhibitor Nutlin-3A restored FBXW7 expression and p63 degradation in a dose-dependent manner and sensitized these cells to apoptosis. Collectively, these data provide a compelling rationale for future investigation of Nutlin-3A as an approach to abrogate acquired resistance of melanoma to MAPK inhibitor targeted therapy.
Significance:
Upregulation of p63, an unreported mechanism of MAPK inhibitor resistance in melanoma, can be abrogated by treatment with the MDM2 inhibitor Nutlin-3A, which may serve as a strategy to overcome resistance.
Data from Peritoneal Spread of Ovarian Cancer Harbors Therapeutic Vulnerabilities Regulated by FOXM1 and EGFR/ERBB2 Signaling
Authors: Parashar Deepak , Nair Bindu , Geethadevi Anjali , George Jasmine , Nair Ajay , Tsaih Shirng-Wern , Kadamberi Ishaque P. , Gopinadhan Nair Gopa Kumar , Lu Yiling , Ramchandran Ramani , Uyar Denise S. , Rader Janet S. , Ram Prahlad T. , Mills Gordon B. , Pradeep Sunila , Chaluvally-Raghavan Pradeep
Published: March 2023

Abstract
Peritoneal spread is the primary mechanism of metastasis of ovarian cancer, and survival of ovarian cancer cells in the peritoneal cavity as nonadherent spheroids and their adherence to the mesothelium of distant organs lead to cancer progression, metastasis, and mortality. However, the mechanisms that govern this metastatic process in ovarian cancer cells remain poorly understood. In this study, we cultured ovarian cancer cell lines in adherent and nonadherent conditions in vitro and analyzed changes in mRNA and protein levels to identify mechanisms of tumor cell survival and proliferation in adherent and nonadherent cells. EGFR or ERBB2 upregulated ZEB1 in nonadherent cells, which caused resistance to cell death and increased tumor-initiating capacity. Conversely, Forkhead box M1 (FOXM1) was required for the induction of integrin β1, integrin-α V, and integrin-α 5 for adhesion of cancer cells. FOXM1 also upregulated ZEB1, which could act as a feedback inhibitor of FOXM1, and caused the transition of adherent cells to nonadherent cells. Strikingly, the combinatorial treatment with lapatinib [dual kinase inhibitor of EGFR (ERBB1) and ERBB2] and thiostrepton (FOXM1 inhibitor) reduced growth and peritoneal spread of ovarian cancer cells more effectively than either single-agent treatment in vivo. In conclusion, these results demonstrate that FOXM1 and EGFR/ERBB2 pathways are key points of vulnerability for therapy to disrupt peritoneal spread and adhesion of ovarian cancer cells.
Significance:
This study describes the mechanism exhibited by ovarian cancer cells required for adherent cell transition to nonadherent form during peritoneal spread and metastasis.
Data from Rare BRIP1 Missense Alleles Confer Risk for Ovarian and Breast Cancer
Authors: Moyer Cassandra L. , Ivanovich Jennifer , Gillespie Jessica L. , Doberstein Rachel , Radke Marc R. , Richardson Marcy E. , Kaufmann Scott H. , Swisher Elizabeth M. , Goodfellow Paul J.
Published: March 2023

Abstract
Germline loss-of-function mutations in BRCA1 interacting protein C-terminal helicase 1 (BRIP1) are associated with ovarian carcinoma and may also contribute to breast cancer risk, particularly among patients who develop disease at an early age. Normal BRIP1 activity is required for DNA interstrand cross-link (ICL) repair and is thus central to the maintenance of genome stability. Although pathogenic mutations have been identified in BRIP1, genetic testing more often reveals missense variants, for which the impact on molecular function and subsequent roles in cancer risk are uncertain. Next-generation sequencing of germline DNA in 2,160 early-onset breast cancer and 1,199 patients with ovarian cancer revealed nearly 2% of patients carry a very rare missense variant (minor allele frequency < 0.0001) in BRIP1. This is 3-fold higher than the frequency of all rare BRIP1 missense alleles reported in more than 60,000 individuals of the general population (P < 0.0001, χ2 test). Using CRISPR-Cas9 gene editing technology and rescue assays, we functionally characterized 20 of these missense variants, focusing on the altered protein's ability to repair ICL damage. A total of 75% of the characterized variants rendered the protein hypomorph or null. In a clinical cohort of >117,000 patients with breast and ovarian cancer who underwent panel testing, the combined OR associated with BRIP1 hypomorph or null missense carriers compared with the general population was 2.30 (95% confidence interval, 1.60–3.30; P < 0.0001). These findings suggest that novel missense variants within the helicase domain of BRIP1 may confer risk for both breast and ovarian cancer and highlight the importance of functional testing for additional variants.
Significance:
Functional characterization of rare variants of uncertain significance in BRIP1 revealed that 75% demonstrate loss-of-function activity, suggesting rare missense alleles in BRIP1 confer risk for both breast and ovarian cancer.
Data from Across-Site Differences in the Mechanism of Alcohol-Induced Digestive Tract Carcinogenesis: An Evaluation by Mediation Analysis
Authors: Koyanagi Yuriko N. , Suzuki Etsuji , Imoto Issei , Kasugai Yumiko , Oze Isao , Ugai Tomotaka , Iwase Madoka , Usui Yoshiaki , Kawakatsu Yukino , Sawabe Michi , Hirayama Yutaka , Tanaka Tsutomu , Abe Tetsuya , Ito Seiji , Komori Koji , Hanai Nobuhiro , Tajika Masahiro , Shimizu Yasuhiro , Niwa Yasumasa , Ito Hidemi , Matsuo Keitaro
Published: March 2023

Abstract
A genetic variant on aldehyde dehydrogenase 2 (ALDH2 rs671, Glu504Lys) contributes to carcinogenesis after alcohol consumption. Somewhat conversely, the ALDH2 Lys allele also confers a protective effect against alcohol-induced carcinogenesis by decreasing alcohol consumption due to acetaldehyde-related adverse effects. Here, we applied a mediation analysis to five case–control studies for head and neck, esophageal, stomach, small intestine, and colorectal cancers, with 4,099 cases and 6,065 controls, and explored the potentially heterogeneous impact of alcohol drinking on digestive tract carcinogenesis by decomposing the total effect of the ALDH2 Lys allele on digestive tract cancer risk into the two opposing effects of the carcinogenic effect (direct effect) and the protective effect (indirect effect mediated by drinking behavior). Alcohol was associated with an increased risk of most digestive tract cancers, but significant direct effects were observed only for upper gastrointestinal tract cancer risk, and varied substantially by site, with ORs (95% confidence interval) of 1.83 (1.43–2.36) for head and neck cancer, 21.15 (9.11–49.12) for esophageal cancer, and 1.65 (1.38–1.96) for stomach cancer. In contrast, a significant protective indirect effect was observed on risk for all cancers, except small intestine cancer. These findings suggest that alcohol is a major risk factor for digestive tract cancers, but its impact as a surrogate for acetaldehyde exposure appears heterogeneous by site. Meanwhile, the behavior-related effect of the ALDH2 Lys allele results in a decreased risk of most digestive tract cancers.
Significance:
These findings support that genetic alcohol avoidance is a factor against alcohol-induced cancers.
Data from PET Reporter Gene Imaging and Ganciclovir-Mediated Ablation of Chimeric Antigen Receptor T Cells in Solid Tumors
Authors: Murty Surya , Labanieh Louai , Murty Tara , Gowrishankar Gayatri , Haywood Tom , Alam Israt S. , Beinat Corinne , Robinson Elise , Aalipour Amin , Klysz Dorota D. , Cochran Jennifer R. , Majzner Robbie G. , Mackall Crystal L. , Gambhir Sanjiv S.
Published: March 2023

Abstract
Imaging strategies to monitor chimeric antigen receptor (CAR) T-cell biodistribution and proliferation harbor the potential to facilitate clinical translation for the treatment of both liquid and solid tumors. In addition, the potential adverse effects of CAR T cells highlight the need for mechanisms to modulate CAR T-cell activity. The herpes simplex virus type 1 thymidine kinase (HSV1-tk) gene has previously been translated as a PET reporter gene for imaging of T-cell trafficking in patients with brain tumor. The HSV1-TK enzyme can act as a suicide gene of transduced cells through treatment with the prodrug ganciclovir. Here we report the molecular engineering, imaging, and ganciclovir-mediated destruction of B7H3 CAR T cells incorporating a mutated version of the HSV1-tk gene (sr39tk) with improved enzymatic activity for ganciclovir. The sr39tk gene did not affect B7H3 CAR T-cell functionality and in vitro and in vivo studies in osteosarcoma models showed no significant effect on B7H3 CAR T-cell antitumor activity. PET/CT imaging with 9-(4-[18F]-fluoro-3-[hydroxymethyl]butyl)guanine ([18F]FHBG) of B7H3-sr39tk CAR T cells in an orthotopic model of osteosarcoma revealed tumor homing and systemic immune expansion. Bioluminescence and PET imaging of B7H3-sr39tk CAR T cells confirmed complete tumor ablation with intraperitoneal ganciclovir administration. This imaging and suicide ablation system can provide insight into CAR T-cell migration and proliferation during clinical trials while serving as a suicide switch to limit potential toxicities.
Significance:
This study showcases the only genetically engineered system capable of serving the dual role both as an effective PET imaging reporter and as a suicide switch for CAR T cells.
Data from The Immunosuppressive Microenvironment in BRCA1-IRIS–Overexpressing TNBC Tumors Is Induced by Bidirectional Interaction with Tumor-Associated Macrophages
Authors: Sami Eman , Paul Bibbin T. , Koziol James A. , ElShamy Wael M.
Published: March 2023

Abstract
Tumor-associated macrophages (TAM) promote triple-negative breast cancer (TNBC) progression. Here, we report BRCA1-IRIS–overexpressing (IRISOE) TNBC cells secrete high levels of GM-CSF in a hypoxia-inducible factor-1α (HIF1α)- and a NF-κB–dependent manner to recruit macrophages to IRISOE cells and polarize them to protumor M2 TAMs. GM-CSF triggered TGFβ1 expression by M2 TAMs by activating STAT5, NF-κB, and/or ERK signaling. Despite expressing high levels of TGFβ1 receptors on their surface, IRISOE TNBC cells channeled TGFβ1/TβRI/II signaling toward AKT, not SMAD, which activated stemness/EMT phenotypes. In orthotopic and syngeneic mouse models, silencing or inactivating IRIS in TNBC cells lowered the levels of circulating GM-CSF, suppressed TAM recruitment, and decreased the levels of circulating TGFβ1. Coinjecting macrophages with IRISOE TNBC cells induced earlier metastasis in athymic mice accompanied by high levels of circulating GM-CSF and TGFβ1. IRISOE TNBC cells expressed low levels of calreticulin (the “eat me” signal for macrophages) and high levels of CD47 (the “do not eat me” signal for macrophages) and PD-L1 (a T-cell inactivator) on their surface. Accordingly, IRISOE TNBC tumors had significantly few CD8+/PD-1+ cytotoxic T cells and more CD25+/FOXP3+ regulatory T cells. These data show that the bidirectional interaction between IRISOE cells and macrophages triggers an immunosuppressive microenvironment within TNBC tumors that is favorable for the generation of immune-evading/stem-like/IRISOE TNBC metastatic precursors. Inhibiting this interaction may inhibit disease progression and enhance patients' overall survival.
Significance:
The BRCA1-IRIS oncogene promotes breast cancer aggressiveness by recruiting macrophages and promoting their M2 polarization.
Data from Pancreatic Adenocarcinoma: Unconventional Approaches for an Unconventional Disease
Authors: Gromisch Christopher , Qadan Motaz , Machado Mariana Albuquerque , Liu Kebin , Colson Yolonda , Grinstaff Mark W.
Published: March 2023

Abstract
This review highlights current treatments, limitations, and pitfalls in the management of pancreatic cancer and discusses current research in novel targets and drug development to overcome these clinical challenges. We begin with a review of the clinical landscape of pancreatic cancer, including genetic and environmental risk factors, as well as limitations in disease diagnosis and prevention. We next discuss current treatment paradigms for pancreatic cancer and the shortcomings of targeted therapy in this disease. Targeting major driver mutations in pancreatic cancer, such as dysregulation in the KRAS and TGFβ signaling pathways, have failed to improve survival outcomes compared with nontargeted chemotherapy; thus, we describe new advances in therapy such as Ras-binding pocket inhibitors. We then review next-generation approaches in nanomedicine and drug delivery, focusing on preclinical advancements in novel optical probes, antibodies, small-molecule agents, and nucleic acids to improve surgical outcomes in resectable disease, augment current therapies, expand druggable targets, and minimize morbidity. We conclude by summarizing progress in current research, identifying areas for future exploration in drug development and nanotechnology, and discussing future prospects for management of this disease.
Data from Integrin β4–Targeted Cancer Immunotherapies Inhibit Tumor Growth and Decrease Metastasis
Authors: Ruan Shasha , Lin Ming , Zhu Yong , Lum Lawrence , Thakur Archana , Jin Runming , Shao Wenlong , Zhang Yalei , Hu Yangyang , Huang Shiang , Hurt Elaine M. , Chang Alfred E. , Wicha Max S. , Li Qiao
Published: March 2023

Abstract
Integrin β4 (ITGB4) has been shown to play an important role in the regulation of cancer stem cells (CSC). Immune targeting of ITGB4 represents a novel approach to target this cell population, with potential clinical benefit. We developed two immunologic strategies to target ITGB4: ITGB4 protein–pulsed dendritic cells (ITGB4-DC) for vaccination and adoptive transfer of anti-CD3/anti-ITGB4 bispecific antibody (ITGB4 BiAb)–armed tumor-draining lymph node T cells. Two immunocompetent mouse models were utilized to assess the efficacy of these immunotherapies in targeting both CSCs and bulk tumor populations: 4T1 mammary tumors and SCC7 head and neck squamous carcinoma cell line. Immunologic targeting of ITGB4 utilizing either ITGB4-DC or ITGB4 BiAb-T cells significantly inhibited local tumor growth and metastases in both the 4T1 and SCC7 tumor models. Furthermore, the efficacy of both of these ITGB4-targeted immunotherapies was significantly enhanced by the addition of anti–PD-L1. Both ITGB4-targeted immunotherapies induced endogenous T-cell cytotoxicity directed at CSCs as well as non-CSCs, which expressed ITGB4, and immune plasma–mediated killing of CSCs. As a result, ITGB4-targeted immunotherapy reduced not only the number of ITGB4high CSCs in residual 4T1 and SCC7 tumors but also their tumor-initiating capacity in secondary mouse implants. In addition, treated mice demonstrated no apparent toxicity. The specificity of these treatments was demonstrated by the lack of effects observed using ITGB4 knockout 4T1 or ITGB4-negative CT26 colon carcinoma cells. Because ITGB4 is expressed by CSCs across a variety of tumor types, these results support immunologic targeting of ITGB4 as a promising therapeutic strategy.

Significance: This study identifies a novel mechanism of resistance to anti–PD-1/PD-L1 immunotherapy mediated by HPV E5, which can be exploited using the HPV E5 inhibitor rimantadine to improve outcomes for head and neck cancer patients.
Data from Hybrid Epithelial–Mesenchymal Phenotypes Are Controlled by Microenvironmental Factors
Authors: Selvaggio Gianluca , Canato Sara , Pawar Archana , Monteiro Pedro T. , Guerreiro Patrícia S. , Brás M. Manuela , Janody Florence , Chaouiya Claudine
Published: March 2023

Abstract
Epithelial-to-mesenchymal transition (EMT) has been associated with cancer cell heterogeneity, plasticity, and metastasis. However, the extrinsic signals supervising these phenotypic transitions remain elusive. To assess how selected microenvironmental signals control cancer-associated phenotypes along the EMT continuum, we defined a logical model of the EMT cellular network that yields qualitative degrees of cell adhesions by adherens junctions and focal adhesions, two features affected during EMT. The model attractors recovered epithelial, mesenchymal, and hybrid phenotypes. Simulations showed that hybrid phenotypes may arise through independent molecular paths involving stringent extrinsic signals. Of particular interest, model predictions and their experimental validations indicated that: (i) stiffening of the extracellular matrix was a prerequisite for cells overactivating FAK_SRC to upregulate SNAIL and acquire a mesenchymal phenotype and (ii) FAK_SRC inhibition of cell–cell contacts through the receptor-type tyrosine-protein phosphatases kappa led to acquisition of a full mesenchymal, rather than a hybrid, phenotype. Altogether, these computational and experimental approaches allow assessment of critical microenvironmental signals controlling hybrid EMT phenotypes and indicate that EMT involves multiple molecular programs.
Significance:
A multidisciplinary study sheds light on microenvironmental signals controlling cancer cell plasticity along EMT and suggests that hybrid and mesenchymal phenotypes arise through independent molecular paths.
Data from An Engineered Tumor-on-a-Chip Device with Breast Cancer–Immune Cell Interactions for Assessing T-cell Recruitment
Authors: Aung Aereas , Kumar Vardhman , Theprungsirikul Jomkuan , Davey Shruti K. , Varghese Shyni
Published: March 2023

Abstract
Recruitment of immune cells to a tumor is determined by the complex interplay between cellular and noncellular components of the tumor microenvironment. Ex vivo platforms that enable identification of key components that promote immune cell recruitment to the tumor could advance the field significantly. Herein, we describe the development of a perfusable multicellular tumor-on-a-chip platform involving different cell populations. Cancer cells, monocytes, and endothelial cells were spatially confined within a gelatin hydrogel in a controlled manner by using 3D photopatterning. The migration of the encapsulated endothelial cells against a chemokine gradient created an endothelial layer around the constructs. Using this platform, we examined the effect of cancer cell–monocyte interaction on T-cell recruitment, where T cells were dispersed within the perfused media and allowed to infiltrate. The hypoxic environment in the spheroid cultures recruited more T cells compared with dispersed cancer cells. Moreover, the addition of monocytes to the cancer cells improved T-cell recruitment. The differences in T-cell recruitment were associated with differences in chemokine secretion including chemokines influencing the permeability of the endothelial barrier. This proof-of-concept study shows how integration of microfabrication, microfluidics, and 3D cell culture systems could be used for the development of tumor-on-a-chip platforms involving heterotypic cells and their application in studying recruitment of cells by the tumor-associated microenvironment.
Significance:
This study describes how tumor-on-chip platforms could be designed to create a heterogeneous mix of cells and noncellular components to study the effect of the tumor microenvironment on immune cell recruitment.
Data from Rb and p53-Deficient Myxofibrosarcoma and Undifferentiated Pleomorphic Sarcoma Require Skp2 for Survival
Authors: Li George Z. , Okada Tomoyo , Kim Young-Mi , Agaram Narasimhan P. , Sanchez-Vega Francisco , Shen Yawei , Tsubokawa Norifumi , Rios Jordan , Martin Axel S. , Dickson Mark A. , Qin Li-Xuan , Socci Nicholas D. , Singer Samuel
Published: March 2023

Abstract
Myxofibrosarcoma (MFS) and undifferentiated pleomorphic sarcoma (UPS) are highly genetically complex soft tissue sarcomas. Up to 50% of patients develop distant metastases, but current systemic therapies have limited efficacy. MFS and UPS have recently been shown to commonly harbor copy number alterations or mutations in the tumor suppressor genes RB1 and TP53. As these alterations have been shown to engender dependence on the oncogenic protein Skp2 for survival of transformed cells in mouse models, we sought to examine its function and potential as a therapeutic target in MFS/UPS. Comparative genomic hybridization and next-generation sequencing confirmed that a significant fraction of MFS and UPS patient samples (n = 94) harbor chromosomal deletions and/or loss-of-function mutations in RB1 and TP53 (88% carry alterations in at least one gene; 60% carry alterations in both). Tissue microarray analysis identified a correlation between absent Rb and p53 expression and positive expression of Skp2. Downregulation of Skp2 or treatment with the Skp2-specific inhibitor C1 revealed that Skp2 drives proliferation of patient-derived MFS/UPS cell lines deficient in both Rb and p53 by degrading p21 and p27. Inhibition of Skp2 using the neddylation-activating enzyme inhibitor pevonedistat decreased growth of Rb/p53-negative patient-derived cell lines and mouse xenografts. These results demonstrate that loss of both Rb and p53 renders MFS and UPS dependent on Skp2, which can be therapeutically exploited and could provide the basis for promising novel systemic therapies for MFS and UPS.
Significance:
Loss of both Rb and p53 renders myxofibrosarcoma and undifferentiated pleomorphic sarcoma dependent on Skp2, which could provide the basis for promising novel systemic therapies.

See related commentary by Lambert and Jones, p. 2437