bluuebunny/crossref_metadata_2025 huggingface dataset:
Data from Chromosome 6p Amplification in Aqueous Humor Cell-Free DNA Is a Prognostic Biomarker for Retinoblastoma Ocular Survival
Authors: Xu Liya , Polski Ashley , Prabakar Rishvanth K. , Reid Mark W. , Chevez-Barrios Patricia , Jubran Rima , Kim Jonathan W. , Kuhn Peter , Cobrinik David , Hicks James , Berry Jesse L.
Published: March 2024

Abstract
Aqueous humor contains tumor-derived cell-free DNA (cfDNA) and can serve as a liquid biopsy for retinoblastoma. We previously associated somatic copy-number alteration (SCNA) 6p gain with a 10-fold increased risk of enucleation. Here we provide a 2-year update to further explore 6p gain as a prognostic biomarker for ocular survival. Patients diagnosed with retinoblastoma from December 2014 to July 2019 from whom aqueous humor was sampled were included. cfDNA was extracted and shallow whole-genome sequencing performed to identify highly recurrent retinoblastoma SCNAs (gain of 1q, 2p, 6p, loss of 13q, 16q). 116 aqueous humor samples from 50 eyes of 46 patients were included: 27 eyes were salvaged, 23 were enucleated. Highly recurrent retinoblastoma SCNAs were found in 66% eyes. 6p gain was the most prevalent SCNA (50% eyes). It was particularly more prevalent in enucleated eyes (73.9%) than in salvaged eyes (29.6%; P = 0.004). 6p gain in aqueous humor cfDNA portended nearly 10-fold increased odds of enucleation (OR = 9.87; 95% confidence interval = 1.75–55.65; P = 0.009). In the enucleated eyes, 6p gain was associated with aggressive histopathologic features, including necrosis, higher degrees of anaplasia, and focal invasion of ocular structures. With extended follow-up and nearly double the aqueous humor samples, we continue to demonstrate 6p gain as a potential prognostic biomarker for retinoblastoma.
Implications:
Aqueous humor is a high-yield source of tumor-derived DNA in retinoblastoma eyes. Detection of 6p gain in the aqueous humor allows for targeted, patient-centered therapies based on this molecular prognostic marker. Prospective, multicenter studies with aqueous humor sampled from all eyes at diagnosis are warranted to validate these findings.
Data from Aberrant Myosin 1b Expression Promotes Cell Migration and Lymph Node Metastasis of HNSCC
Authors: Ohmura Gaku , Tsujikawa Takahiro , Yaguchi Tomonori , Kawamura Naoshi , Mikami Shuji , Sugiyama Juri , Nakamura Kenta , Kobayashi Asuka , Iwata Takashi , Nakano Hiroshi , Shimada Taketoshi , Hisa Yasuo , Kawakami Yutaka
Published: March 2024

Abstract
Lymph node metastasis is the major clinicopathologic feature associated with poor prognosis in patients with head and neck squamous cell carcinoma (HNSCC). Here, web-based bioinformatics meta-analysis was performed to elucidate the molecular mechanism of lymph node metastasis of human HNSCC. Preferential upregulation of Myosin 1b (MYO1B) transcript in HNSCC datasets was identified. Myo1b mRNA was highly expressed in human HNSCC cells and patient tissue specimens compared with their normal counterparts as shown by quantitative PCR (qPCR) analyses. Immunohistochemistry (IHC)-detected Myo1b expression was significantly correlated with lymph node metastases in patients with oral cancer of the tongue. HNSCC with high expression of Myo1b and chemokine receptor 4 (CCR4), another metastasis-associated molecule, was strongly associated with lymph node metastasis. RNA interference (RNAi) of Myo1b in HNSCC cells, SAS and HSC4, significantly inhibited migratory and invasive abilities through decreased large protrusion formation of cell membranes. Finally, Myo1b knockdown in SAS cells significantly inhibited in vivo cervical lymph node metastases in a cervical lymph node metastatic mouse model system.

Implications: Myo1b is functionally involved in lymph node metastasis of human HNSCC through enhanced cancer cell motility and is an attractive target for new diagnostic and therapeutic strategies for patients with HNSCC. Mol Cancer Res; 13(4); 721–31. ©2014 AACR.
Data from KLF4 Suppresses Tumor Formation in Genetic and Pharmacological Mouse Models of Colonic Tumorigenesis
Authors: Ghaleb Amr M. , Elkarim Enas A. , Bialkowska Agnieszka B. , Yang Vincent W.
Published: March 2024

Abstract
The zinc finger transcription factor Krüppel-like factor 4 (KLF4) is frequently downregulated in colorectal cancer. Previous studies showed that KLF4 is a tumor suppressor in the intestinal tract and plays an important role in DNA damage-repair mechanisms. Here, the in vivo effects of Klf4 deletion were examined from the mouse intestinal epithelium (Klf4ΔIS) in a genetic or pharmacological setting of colonic tumorigenesis: ApcMin/+ mutation or carcinogen treatment with azoxymethane (AOM), respectively. Klf4ΔIS/ApcMin/+ mice developed significantly more colonic adenomas with 100% penetrance as compared with ApcMin/+ mice with intact Klf4 (Klf4fl/fl/ApcMin/+). The colonic epithelium of Klf4ΔIS/ApcMin/+ mice showed increased mTOR pathway activity, together with dysregulated epigenetic mechanism as indicated by altered expression of HDAC1 and p300. Colonic adenomas from both genotypes stained positive for γH2AX, indicating DNA double-strand breaks. In Klf4ΔIS/ApcMin/+ mice, this was associated with reduced nonhomologous end joining (NHEJ) repair and homologous recombination repair (HRR) mechanisms as indicated by reduced Ku70 and Rad51 staining, respectively. In a separate model, following treatment with AOM, Klf4ΔIS mice developed significantly more colonic tumors than Klf4fl/fl mice, with more Klf4ΔIS mice harboring K-Ras mutations than Klf4fl/fl mice. Compared with AOM-treated Klf4fl/fl mice, adenomas of treated Klf4ΔIS mice had suppressed NHEJ and HRR mechanisms, as indicated by reduced Ku70 and Rad51 staining. This study highlights the important role of KLF4 in suppressing the development of colonic neoplasia under different tumor-promoting conditions.

Implications: The study demonstrates that KLF4 plays a significant role in the pathogenesis of colorectal neoplasia. Mol Cancer Res; 14(4); 385–96. ©2016 AACR.
Data from CD71+ Population Enriched by HPV-E6 Protein Promotes Cancer Aggressiveness and Radioresistance in Cervical Cancer Cells
Authors: Leung Thomas Ho-Yin , Tang Hermit Wai-Man , Siu Michelle Kwan-Yee , Chan David Wai , Chan Karen Kar-Loen , Cheung Annie Nga-Yin , Ngan Hextan Yuen-Sheung
Published: March 2024

Abstract
A subpopulation of cells within tumors has been suggested to possess the ability to initiate tumorigenesis and contribute to resistance to cancer therapy. Identification and isolation of this subpopulation in cancer cells can be achieved by detecting specific cell-surface markers. In this study, flow cytometry analysis revealed an abundant CD71+ subpopulation in human papillomavirus (HPV)-positive cervical cancer cells, while limited CD71+ cells were detected in HPV-negative cervical cancer cells. Furthermore, ectopic expression of the HPV-E6 protein in HPV-negative C33A cells enriched the CD71+subpopulation. The CD71+ subpopulation isolated from the C33A cell line and an HPV-E6–overexpressing clone exhibited enhanced transforming ability, proliferation, and resistance to irradiation. In contrast, suppression of CD71 in HPV-positive SiHa cells and the HPV-E6–overexpressing stable clone inhibited spheroid formation and in vitro and in vivo tumorigenicity and sensitized cells to irradiation treatment. CRISPR/Cas9 knockout of CD71 in SiHa cells also produced similar inhibitory effects on tumorigenicity. Double knockout of CD71 and CD55 reversed the oncogenic properties of the HPV-E6–overexpressing clone. These findings suggest that the HPV-E6 protein enriches the subpopulation of CD71+cells in cervical cancer, which exhibit cancer stem–like cell properties and are resistant to irradiation treatment. Targeting the CD71+ subpopulation in cervical cancer cells with siRNAs or CRISPR/Cas9 may provide new insights for the development of novel therapeutic approaches for treating cervical cancer.
Implications:
We describe the enrichment of CD71+ population by HPV-E6 protein in cervical cancer cells that promotes cancer aggressiveness and resistance to irradiation treatment.
Data from Breast Cancer–Specific miR Signature Unique to Extracellular Vesicles Includes “microRNA-like” tRNA Fragments
Authors: Guzman Nicole , Agarwal Kitty , Asthagiri Dilip , Yu Lianbo , Saji Motoyasu , Ringel Matthew D. , Paulaitis Michael E.
Published: March 2024

Abstract
Extracellular vesicles (EV), including exosomes and shed vesicles, have been implicated in intercellular communication; however, their biomarker potential is less clear. Therefore, EVs derived from MCF7 and MCF10A cells were analyzed to identify unique miRNA (miR) profiles that distinguish their origin. One characteristic common to the miR profiles of MCF7 EVs and their parent cells is the high abundance of miR-21, let-7a, miR-100, and miR-125b, and low levels of miR-205. A second characteristic is the high abundance of “miRNA-like” tRNA fragments, which is unique to the MCF7 EVs, and is not found in comparing the cellular profiles. In addition, correlations were examined in the MCF7 cellular expression levels of these five miRs and two tRNA-derived miRNAs, miR-720 and miR-1274b, and compared with the correlations in MCF7 EV levels. Interestingly, correlations in the cellular expression of miR-125b, miR-100, and let-7a are mirrored in the EVs. In contrast, correlations in tRNA-derived miRNA levels are found only in the EVs. The findings suggest that EV miR clusters can be defined based on functional miR interactions related to correlated cellular expression levels or physical miR interactions, for example, aggregation due to comparable binding affinities to common targets.

Implications: These results point to using high levels of tRNA-derived small RNA fragments in combination with known miR signatures of tumors to distinguish tumor-derived EVs in circulation from EVs derived from other cell sources. Such biomarkers would be unique to the EVs where high abundances of tRNA fragments are amplified with respect to their cellular levels. Mol Cancer Res; 13(5); 891–901. ©2015 AACR.
Data from Inhibition of the Cell Death Pathway in Nonalcoholic Steatohepatitis (NASH)-Related Hepatocarcinogenesis Is Associated with Histone H4 lysine 16 Deacetylation
Authors: de Conti Aline , Dreval Kostiantyn , Tryndyak Volodymyr , Orisakwe Orish E. , Ross Sharon A. , Beland Frederick A. , Pogribny Igor P.
Published: March 2024

Abstract
Hepatocellular carcinoma (HCC) is one of the most aggressive human cancers, and its incidence is steadily increasing worldwide. Recent epidemiologic findings have suggested that the increased incidence of HCC is associated with obesity, type II diabetes mellitus, and nonalcoholic steatohepatitis (NASH); however, the mechanisms and the molecular pathogenesis of NASH-related HCC are not fully understood. To elucidate the underlying mechanisms of the development of NASH-related HCC, we investigated the hepatic transcriptomic and histone modification profiles in Stelic Animal Model mice, the first animal model of NASH-related HCC to resemble the disease pathogenesis in humans. The results demonstrate that the development of NASH-related HCC is characterized by progressive transcriptomic alterations, global loss of histone H4 lysine 20 trimethylation (H4K20me3), and global and gene-specific deacetylation of histone H4 lysine 16 (H4K16). Pathway analysis of the entire set of differentially expressed genes indicated that the inhibition of cell death pathway was the most prominent alteration, and this was facilitated by persistent gene-specific histone H4K16 deacetylation. Mechanistically, deacetylation of histone H4K16 was associated with downregulation of lysine acetyltransferase KAT8, which was driven by overexpression of its inhibitor nuclear protein 1 (Nupr1). The results of this study identified a reduction of global and gene-specific histone H4K16 acetylation as a key pathophysiologic mechanism contributing to the development of NASH-derived HCC and emphasized the importance of epigenetic alterations as diagnostic and therapeutic targets for HCC.

Implications: Histone H4K16 deacetylation induces silencing of genes related to the cell death that occurred during the development of NASH-related HCC. Mol Cancer Res; 15(9); 1163–72. ©2017 AACR.
Data from Homologous Mutation to Human BRAF V600E Is Common in Naturally Occurring Canine Bladder Cancer—Evidence for a Relevant Model System and Urine-Based Diagnostic Test
Authors: Decker Brennan , Parker Heidi G. , Dhawan Deepika , Kwon Erika M. , Karlins Eric , Davis Brian W. , Ramos-Vara José A. , Bonney Patty L. , McNiel Elizabeth A. , Knapp Deborah W. , Ostrander Elaine A.
Published: March 2024

Abstract
Targeted cancer therapies offer great clinical promise, but treatment resistance is common, and basic research aimed at overcoming this challenge is limited by reduced genomic and biologic complexity in artificially induced rodent tumors compared with their human counterparts. Animal models that more faithfully recapitulate genotype-specific human pathology could improve the predictive value of these investigations. Here, a newly identified animal model for oncogenic BRAF-driven cancers is described. With 20,000 new cases in the United States each year, canine invasive transitional cell carcinoma of the bladder (InvTCC) is a common, naturally occurring malignancy that shares significant histologic, biologic, and clinical phenotypes with human muscle invasive bladder cancer. In order to identify somatic drivers of canine InvTCC, the complete transcriptome for multiple tumors was determined by RNAseq. All tumors harbored a somatic mutation that is homologous to the human BRAF(V600E) mutation, and an identical mutation was present in 87% of 62 additional canine InvTCC tumors. The mutation was also detectable in the urine sediments of all dogs tested with mutation-positive tumors. Functional experiments suggest that, like human tumors, canine activating BRAF mutations potently stimulate the MAPK pathway. Cell lines with the mutation have elevated levels of phosphorylated MEK, compared with a line with wild-type BRAF. This effect can be diminished through application of the BRAF(V600E) inhibitor vemurafenib. These findings set the stage for canine InvTCC as a powerful system to evaluate BRAF-targeted therapies, as well as therapies designed to overcome resistance, which could enhance treatment of both human and canine cancers

Implications: This study demonstrates the activating BRAF mutation (V600E), which is found in multiple human cancers, is a driver of canine InvTCC, and highlights a urine-based test for quick diagnosis. Mol Cancer Res; 13(6); 993–1002. ©2015 AACR.
Data from Molecular Portrait of Hypoxia in Breast Cancer: A Prognostic Signature and Novel HIF-Regulated Genes
Authors: Ye I. Chae , Fertig Elana J. , DiGiacomo Josh W. , Considine Michael , Godet Inês , Gilkes Daniele M.
Published: March 2024

Abstract
Intratumoral hypoxia has been associated with invasion, metastasis, and treatment failure, prompting the need for a global characterization of the response to hypoxic conditions. The current study presents the results of a large-scale RNA sequencing (RNA-seq) effort, analyzing 31 breast cancer cell lines representative of breast cancer subtypes or normal mammary epithelial (NME) cells exposed to control tissue culture conditions (20% O2) or hypoxic conditions (1% O2). The results demonstrate that NME have a stronger response to hypoxia both in terms of number of genes induced by hypoxia as well as level of expression. A conserved 42-gene hypoxia signature shared across PAM50 subtypes and genes that are exclusively upregulated in Luminal A, Luminal B, and normal-like mammary epithelial cells is identified. The 42-gene expression signature is enriched in a subset of basal-like cell lines and tumors and differentiates survival among patients with basal-like tumors. Mechanistically, the hypoxia-inducible factors (HIF-1 and/or HIF-2) mediate the conserved hypoxic response. Also, four novel hypoxia-regulated and HIF-1–responsive genes were identified as part of the conserved signature. This dataset provides a novel resource to query transcriptional changes that occur in response to hypoxia and serves as a starting point for a clinical assay to aid in stratifying patients that would benefit from hypoxia-targeted therapies, some of which are currently in clinical trials.
Implications:
RNA-seq of 31 breast cancer cells exposed to control or hypoxic conditions reveals a conserved genomic signature that contains novel HIF-regulated genes and is prognostic for the survival of patients with triple-negative breast cancer.
Data from Sympathetic Signaling Reactivates Quiescent Disseminated Prostate Cancer Cells in the Bone Marrow
Authors: Decker Ann M. , Jung Younghun , Cackowski Frank C. , Yumoto Kenji , Wang Jingchen , Taichman Russel S.
Published: March 2024

Abstract
Clinical observations have identified an association between psychologic stress and cancer relapse, suggesting that the sympathetic nervous system/norepinephrine (NE) plays a role in reactivation of dormant disseminated tumor cells (DTC) in the bone marrow niche. Here, the mechanism by which NE regulates prostate cancer DTCs in the marrow is explored. NE directly stimulated prostate cancer cell proliferation through β2-adrenergic receptors (ADRB2). NE also altered prostate cancer proliferation in the marrow niche by indirectly downregulating the secretion of the dormancy inducing molecule growth arrest specific-6 (GAS6) expressed by osteoblasts. These observations were confirmed in cocultures of prostate cancer cells expressing the fluorescent ubiquitination-based cell-cycle reporters (FUCCI) and osteoblasts isolated from GAS6-deficient (GAS6−/−) animals. A novel ex vivo model system, using femurs harvested from GAS6+/+ or GAS6−/− mice, was used to confirm these results. As in coculture, when prostate cancer cells were injected into the marrow cavities of GAS6+/+ femurs, NE altered the prostate cancer cell cycle. However, NE had less of an impact on prostate cancer cells in femur explants isolated from GAS6−/− mice. Together, this study demonstrates that NE reactivates prostate cancer cell cycling through both a direct action on prostate cancer cells and indirectly on adjacent niche cells.

Implications: Identification of mechanisms that target DTCs may provide novel therapeutic approaches to prevent or treat cancer metastases more effectively. Mol Cancer Res; 15(12); 1644–55. ©2017 AACR.
Data from Tumor Progression Is Mediated by Thymosin-β4 through a TGFβ/MRTF Signaling Axis
Authors: Morita Tsuyoshi , Hayashi Ken'ichiro
Published: March 2024

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

Implications: These findings define a molecular mechanism underlying a tumor-promoting function of thymosin β4 through activation of MRTF/SRF signaling. Mol Cancer Res; 16(5); 880–93. ©2018 AACR.
Data from Genomic cfDNA Analysis of Aqueous Humor in Retinoblastoma Predicts Eye Salvage: The Surrogate Tumor Biopsy for Retinoblastoma
Authors: Berry Jesse L. , Xu Liya , Kooi Irsan , Murphree A. Linn , Prabakar Rishvanth K. , Reid Mark , Stachelek Kevin , Le Bao Han A. , Welter Lisa , Reiser Bibiana J. , Chévez-Barrios Patricia , Jubran Rima , Lee Thomas C. , Kim Jonathan W. , Kuhn Peter , Cobrinik David , Hicks James
Published: March 2024

Abstract
Tumor-derived cell-free DNA (cfDNA) has biomarker potential; therefore, this study aimed to identify cfDNA in the aqueous humor (AH) of retinoblastoma eyes and correlate somatic chromosomal copy-number alterations (SCNA) with clinical outcomes, specifically eye salvage. AH was extracted via paracentesis during intravitreal injection of chemotherapy or enucleation. Shallow whole-genome sequencing was performed using isolated cfDNA to assess for highly recurrent SCNAs in retinoblastoma including gain of 1q, 2p, 6p, loss of 13q, 16q, and focal MYCN amplification. Sixty-three clinical specimens of AH from 29 eyes of 26 patients were evaluated; 13 eyes were enucleated and 16 were salvaged (e.g., saved). The presence of detectable SCNAs was 92% in enucleated eyes versus 38% in salvaged eyes (P = 0.006). Gain of chromosome 6p was the most common SCNA found in 77% of enucleated eyes, compared with 25% of salvaged eyes (P = 0.0092), and associated with a 10-fold increased odds of enucleation (OR, 10; 95% CI, 1.8–55.6). The median amplitude of 6p gain was 1.47 in enucleated versus 1.07 in salvaged eyes (P = 0.001). The presence of AH SCNAs was correlated retrospectively with eye salvage. The probability of ocular salvage was higher in eyes without detectable SCNAs in the AH (P = 0.0028), specifically 6p gain. This is the first study to correlate clinical outcomes with SCNAs in the AH from retinoblastoma eyes, as such these findings indicate that 6p gain in the aqueous humor is a potential prognostic biomarker for poor clinical response to therapy.

Implications: The correlation of clinical outcomes and SCNAs in the AH identified in the current study requires prospective studies to validate these finding before SCNAs, like 6p gain, can be used to predict clinical outcomes at diagnosis. Mol Cancer Res; 16(11); 1701–12. ©2018 AACR.
Data from Integrated Genomic Comparison of Mouse Models Reveals Their Clinical Resemblance to Human Liver Cancer
Authors: Yim Sun Young , Shim Jae-Jun , Shin Ji-Hyun , Jeong Yun Seong , Kang Sang-Hee , Kim Sang-Bae , Eun Young Gyu , Lee Dong Jin , Conner Elizabeth A. , Factor Valentina M. , Moore David D. , Johnson Randy L. , Thorgeirsson Snorri S. , Lee Ju-Seog
Published: March 2024

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

Implication: The current genomic approach identified the most relevant mouse models to human liver cancer and suggests immunotherapeutic potential for the treatment of specific subtypes. Mol Cancer Res; 16(11); 1713–23. ©2018 AACR.
Data from The Aged Microenvironment Influences the Tumorigenic Potential of Malignant Prostate Epithelial Cells
Authors: Bianchi-Frias Daniella , Damodarasamy Mamatha , Hernandez Susana A. , Gil da Costa Rui M. , Vakar-Lopez Funda , Coleman Ilsa M. , Reed May J. , Nelson Peter S.
Published: March 2024

Abstract
The incidence of prostate cancer is directly linked to age, but age-associated changes that facilitate prostate cancer development and progression are poorly understood. This study investigated age-related changes in the prostate microenvironment for their influence on prostate cancer behavior. Prostate cancer cells implanted orthotopically into the prostate demonstrated accelerated tumor growth in aged compared with young mice. Metastatic lesions following intravenous injection were also more numerous in aged mice. Tumors from young and aged mice showed no significant differences concerning their proliferation index, apoptosis, or angiogenesis. However, analysis of tumor-infiltrating immune cells by IHC and RNA sequencing (RNA-seq) revealed elevated numbers of macrophages in prostates from aged mice, which are quickly polarized towards a phenotype resembling protumorigenic tumor-associated macrophages upon tumor cell engraftment. Older patients with prostate cancer (>60 years old) in The Cancer Genome Atlas Prostate Adenocarcinoma (TCGA-PRAD) dataset displayed higher expression of macrophage markers (CD163 and VSIG4) which associated with higher rates of biochemical relapse. Remodeling of the collagenous extracellular matrix (ECM) was associated with prostate cancer growth and invasion in the aged microenvironment. Moreover, the collagen matrix extracted from aged mice enhanced the invasiveness and proliferation of prostate cancer cells in vitro. Together, these results demonstrate that the aged prostatic microenvironment can regulate the growth and metastasis of malignant prostate cells, highlighting the role of resident macrophages and their polarization towards a protumorigenic phenotype, along with remodeling of the ECM.
Implications:
These findings demonstrate the importance of age-associated tumor microenvironment alterations in regulating key aspects of prostate cancer progression.
Data from Functional Analysis of Aberrantly Spliced Caspase8 Variants in Adult T-Cell Leukemia Cells
Authors: Nakano Kazumi , Iwanaga Masako , Utsunomiya Atae , Uchimaru Kaoru , Watanabe Toshiki
Published: March 2024

Abstract
The genetic and molecular alterations responsible for leukemogenesis and progression of HTLV-infected adult T-cell leukemia (ATL) have not been fully clarified. Previously, we reported that various genes are not only overexpressed but also abnormally spliced in ATL cells. Here, we identified various CASP8 transcript variants in PBMCs from a smoldering-type ATL patient, which encode aberrant truncated caspase 8 (Casp8) isoforms. Among those, we focus on the three transcript variants, CASP8L (including the first 136 bp of the intron 8 between exon 8 and exon 9), CASP8-ΔE4 (without the exon 4), and CASP8-ΔE7 (without the exon 7), because they encode isoforms, Casp8L, Casp8-ΔE4, and Casp8-ΔE7, respectively, without the C-terminal catalytic domains. In this study, we conducted in vitro characterization and functional analysis of those mutant Casp8 isoforms to clarify their changed functions compared with the wild-type (WT)-Casp8. We demonstrated that these abnormal Casp8 isoforms showed lower ability to induce apoptosis than WT-Casp8 due to their dominant-negative interactions with WT-Casp8, which impair WT-Casp8 homodimerization that is essential for induction of apoptosis. Moreover, Casp8L and Casp8-ΔE7, which have only two death-effector domains, significantly activated NFκB by forming filament-like structures, which probably function as scaffolds for the IKK complex formation. In view of increasing levels of these abnormal CASP8 transcripts in primary PBMCs from HTLV-1 carriers and patients with ATL, we propose a possibility that overexpression of those Casp8 mutants, with lower proapoptotic activities and higher NFκB-activating functions than WT-Casp8, may be one of the molecular abnormalities causing malignant transformation and growth of ATL cells.
Implications:
We describe naturally occurring CASP8 transcription variants in PBMCs from patients with ATL, which encode truncated Casp8-mutant isoforms with lower proapoptotic activities and higher NFκB-activating functions compared with WT-Casp8.
Data from Novel Regulation of Integrin Trafficking by Rab11-FIP5 in Aggressive Prostate Cancer
Authors: Das Lipsa , Gard Jaime M.C. , Prekeris Rytis , Nagle Raymond B. , Morrissey Colm , Knudsen Beatrice S. , Miranti Cindy K. , Cress Anne E.
Published: March 2024

Abstract
The laminin-binding integrins, α3β1 and α6β1, are needed for tumor metastasis and their surface expression is regulated by endocytic recycling. β1 integrins share the Rab11 recycling machinery, but the trafficking of α3β1 and α6β1 are distinct by an unknown mechanism. Using a mouse PDX tumor model containing human metastatic prostate cancer, Rab11 family interacting protein 5 (Rab11-FIP5) was identified as a lead candidate for α6β1 trafficking. Rab11-FIP5 and its membrane-binding domain were required for α6β1 recycling, without affecting the other laminin-binding integrin (i.e., α3β1) or unrelated membrane receptors like CD44, transferrin receptor, or E-cadherin. Depletion of Rab11-FIP5 resulted in the intracellular accumulation of α6β1 in the Rab11 recycling compartment, loss of cell migration on laminin, and an unexpected loss of α6β1 recycling in cell–cell locations. Taken together, these data demonstrate that α6β1 is distinct from α3β1 via Rab11-FIP5 recycling and recycles in an unexpected cell–cell location.

Implications: Rab11-FIP5–dependent α6β1 integrin recycling may be selectively targeted to limit migration of prostate cancer cells into laminin-rich tissues. Mol Cancer Res; 16(8); 1319–31. ©2018 AACR.
Data from The Codon 72 TP53 Polymorphism Contributes to TSC Tumorigenesis through the Notch–Nodal Axis
Authors: Cho Jun-Hung , Patel Bhaumik , Bonala Santosh , Mansouri Hossein , Manne Sasikanth , Vadrevu Surya Kumari , Ghouse Shanawaz , Kung Che-Pei , Murphy Maureen E. , Astrinidis Aristotelis , Henske Elizabeth P. , Kwiatkowski David J. , Markiewski Maciej M. , Karbowniczek Magdalena
Published: March 2024

Abstract
We discovered that 90.3% of patients with angiomyolipomas, lymphangioleiomyomatosis (LAM), and tuberous sclerosis complex (TSC) carry the arginine variant of codon 72 (R72) of TP53 and that R72 increases the risk for angiomyolipoma. R72 transactivates NOTCH1 and NODAL better than the proline variant of codon 72 (P72); therefore, the expression of NOTCH1 and NODAL is increased in angiomyolipoma cells that carry R72. The loss of Tp53 and Tsc1 within nestin-expressing cells in mice resulted in the development of renal cell carcinomas (RCC) with high Notch1 and Nodal expression, suggesting that similar downstream mechanisms contribute to tumorigenesis as a result of p53 loss in mice and p53 polymorphism in humans. The loss of murine Tp53 or expression of human R72 contributes to tumorigenesis via enhancing epithelial-to-mesenchymal transition and motility of tumor cells through the Notch and Nodal pathways.
Implications:
This work revealed unexpected contributions of the p53 polymorphism to the pathogenesis of TSC and established signaling alterations caused by this polymorphism as a target for therapy. We found that the codon 72 TP53 polymorphism contributes to TSC-associated tumorigenesis via Notch and Nodal signaling.
Data from The Hypoxic Tumor Microenvironment Promotes Invadopodia Formation and Metastasis through LPA1 Receptor and EGFR Cooperation
Authors: Harper Kelly , R. Lavoie Roxane , Charbonneau Martine , Brochu-Gaudreau Karine , Dubois Claire M.
Published: March 2024

Abstract
Hypoxia, a common feature of solid tumors, has been critically involved in cell invasion and metastasis, but the underlying mechanisms remain poorly understood. Previously, it has been observed that the lysophosphatidic acid receptor 4 (LPA4) signaling axis mediates production of the degradative subcellular structures invadopodia, which are known to be required for metastasis. Here, it is demonstrated that LPA1 (LPAR1) is a common and major receptor used for hypoxia-induced invadopodia production in various cancer cell lines. The widespread use of LPA1 was not due to increased LPA1 expression but rather relied on Src-mediated cross-talk with EGFR. LPA1-mediated phosphorylation of Y845-EGFR under hypoxia led to PI3K/Akt activation, an event that increases the ability of cells to produce invadopodia. Moreover, phospho-Y845-EGFR was upregulated in hypoxic zones of tumors and a combination of EGFR and LPA1 inhibition synergistically suppressed metastasis in vivo.

Implications: This study uncovers an LPA1–EGFR signaling axis that is used for cell invasion in hypoxia and suggests a potential target to impede cancer metastasis. Mol Cancer Res; 16(10); 1601–13. ©2018 AACR.
Data from Metformin Reduces Prostate Tumor Growth, in a Diet-Dependent Manner, by Modulating Multiple Signaling Pathways
Authors: Sarmento-Cabral André , L-López Fernando , Gahete Manuel D. , Castaño Justo P. , Luque Raúl M.
Published: March 2024

Abstract
Prostate-cancer is strongly influenced by obesity, wherein metformin could represent a promising treatment; however, the endocrine metabolic/cellular/molecular mechanisms underlying these associations and effects are still unclear. To determine the beneficial antitumoral effects of metformin on prostate cancer progression/aggressiveness and the relative contribution of high-fat diet (HFD; independently of obesity), we used HFD-fed immunosuppressed mice inoculated with PC3 cells (which exhibited partial resistance to diet-induced obesity) compared with low-fat diet (LFD)-fed control mice. Moreover, gene expression analysis was performed on cancer-associated genes in the xenografted tumors, and the antitumorigenic role of metformin on tumoral (PC3/22Rv1/LNCaP) and normal (RWPE1) prostate cells was evaluated. The results demonstrate that HFD is associated with enhanced prostate cancer growth irrespective of body weight gain and endocrine metabolic dysregulations and that metformin can reduce prostate cancer growth under LFD but more prominently under HFD, acting through the modulation of several tumoral-associated processes (e.g., cell cycle, apoptosis, and/or necrosis). Moreover, the actions observed in vivo could be mediated by the modulation of the local expression of GH/IGF1 axis components. Finally, it was demonstrated that metformin had disparate effects on proliferation, migration, and prostate-specific antigen secretion from different cell lines. Altogether, these data reveal that metformin inhibits prostate cancer growth under LFD and, specially, under HFD conditions through multiple metabolic/tumoral signaling pathways.

Implications: The current study linking dietary influence on metformin-regulated signaling pathways and antitumoral response provides new and critical insight on environment–host interactions in cancer and therapy. Mol Cancer Res; 15(7); 862–74. ©2017 AACR.
Data from Transient Telomerase Inhibition with Imetelstat Impacts DNA Damage Signals and Cell-Cycle Kinetics
Authors: Thompson Connor A.H. , Gu Alice , Yang Sunny Y. , Mathew Veena , Fleisig Helen B , Wong Judy M.Y.
Published: March 2024

Abstract
Telomerase is the ribonucleoprotein reverse transcriptase that catalyzes the synthesis of telomeres at the ends of linear chromosomes and contributes to proper telomere-loop (T-loop) formation. Formation of the T-loop, an obligate step before cell division can proceed, requires the generation of a 3′-overhang on the G-rich strand of telomeric DNA via telomerase or C-strand specific nucleases. Here, it is discovered that telomerase activity is critical for efficient cell-cycle progression using transient chemical inhibition by the telomerase inhibitor, imetelstat. Telomerase inhibition changed cell cycle kinetics and increased the proportion of cells in G2-phase, suggesting delayed clearance through this checkpoint. Investigating the possible contribution of unstructured telomere ends to these cell-cycle distribution changes, it was observed that imetelstat treatment induced γH2AX DNA damage foci in a subset of telomerase-positive cells but not telomerase-negative primary human fibroblasts. Chromatin-immunoprecipitation with γH2AX antibodies demonstrated imetelstat treatment-dependent enrichment of this DNA damage marker at telomeres. Notably, the effects of telomerase inhibition on cell cycle profile alterations were abrogated by pharmacological inhibition of the DNA-damage-repair transducer, ATM. Also, imetelstat potentiation of etoposide, a DNA-damaging drug that acts preferentially during S–G2 phases of the cell cycle, depends on functional ATM signaling. Thus, telomerase inhibition delays the removal of ATM-dependent DNA damage signals from telomeres in telomerase-positive cancer cells and interferes with cell cycle progression through G2.

Implications: This study demonstrates that telomerase activity directly facilitates the progression of the cell cycle through modulation of transient telomere dysfunction signals. Mol Cancer Res; 16(8); 1215–25. ©2018 AACR.
Data from Therapeutic Targeting of CD146/MCAM Reduces Bone Metastasis in Prostate Cancer
Authors: Zoni Eugenio , Astrologo Letizia , Ng Charlotte K.Y. , Piscuoglio Salvatore , Melsen Janine , Grosjean Joël , Klima Irena , Chen Lanpeng , Snaar-Jagalska Ewa B. , Flanagan Kenneth , van der Pluijm Gabri , Kloen Peter , Cecchini Marco G. , Kruithof-de Julio Marianna , Thalmann George N.
Published: March 2024

Abstract
Prostate Cancer is the most common cancer and the second leading cause of cancer-related death in males. When prostate cancer acquires castration resistance, incurable metastases, primarily in the bone, occur. The aim of this study is to test the applicability of targeting melanoma cell adhesion molecule (MCAM; CD146) with a mAb for the treatment of lytic prostate cancer bone metastasis. We evaluated the effect of targeting MCAM using in vivo preclinical bone metastasis models and an in vitro bone niche coculture system. We utilized FACS, cell proliferation assays, and gene expression profiling to study the phenotype and function of MCAM knockdown in vitro and in vivo. To demonstrate the impact of MCAM targeting and therapeutic applicability, we employed an anti-MCAM mAb in vivo. MCAM is elevated in prostate cancer metastases resistant to androgen ablation. Treatment with DHT showed MCAM upregulation upon castration. We investigated the function of MCAM in a direct coculture model of human prostate cancer cells with human osteoblasts and found that there is a reduced influence of human osteoblasts on human prostate cancer cells in which MCAM has been knocked down. Furthermore, we observed a strongly reduced formation of osteolytic lesions upon bone inoculation of MCAM-depleted human prostate cancer cells in animal model of prostate cancer bone metastasis. This phenotype is supported by RNA sequencing (RNA-seq) analysis. Importantly, in vivo administration of an anti-MCAM human mAb reduced the tumor growth and lytic lesions. These results highlight the functional role for MCAM in the development of lytic bone metastasis and suggest that MCAM is a potential therapeutic target in prostate cancer bone metastasis.
Implications:
This study highlights the functional application of an anti-MCAM mAb to target prostate cancer bone metastasis.
Data from Mutational Landscape of Ovarian Adult Granulosa Cell Tumors from Whole Exome and Targeted TERT Promoter Sequencing
Authors: Alexiadis Maria , Rowley Simone M. , Chu Simon , Leung Dilys T.H. , Stewart Colin J.R. , Amarasinghe Kaushalya C. , Campbell Ian G. , Fuller Peter J.
Published: March 2024

Abstract
Adult granulosa cell tumor (aGCT), the most common malignant ovarian sex cord-stromal tumor, is characterized by the forkhead transcription factor FOXL2 p.C134W somatic mutation. Late recurrences are relatively common but the molecular mechanisms of relapse or aggressive behavior are not known. The mutational landscape of FOXL2 p.C134W mutation–positive tumors (n = 22) was determined using whole-exome sequencing (WES). An average of 64 coding and essential splice-site variants were identified per tumor. As the TERT promoter region is poorly covered by the WES, targeted sequencing identified the TERT -124C>T promoter mutation as the only recurrent mutation (∼40% of cases). Pathway analysis suggested an association with DNA replication/repair and the EGFR family canonical pathways. Copy number analysis confirmed that gains of chromosomes 12 and 14 occur in approximately 30% of aGCT and loss of chromosome 22 occurs in approximately 40% of cases. In summary, exome-wide analysis of the mutational landscape of aGCT revealed that, except for the TERT promoter mutation, recurrence and/or aggressive behavior is not defined by activation or loss of specific genes.
Implications:
This study found that although aGCTs are defined by the presence of a common FOXL2 gene mutation, recurrence and/or aggressive behavior cannot be attributed to subsequent mutation of specific gene(s) or pathways; however, there is a high frequency of the TERT -124C>T promoter mutation, which is associated with more aggressive disease.
Data from HBx-K130M/V131I Promotes Liver Cancer in Transgenic Mice via AKT/FOXO1 Signaling Pathway and Arachidonic Acid Metabolism
Authors: Chiu Amy P. , Tschida Barbara R. , Sham Tung-Ting , Lo Lilian H. , Moriarity Branden S. , Li Xiao-Xiao , Lo Regina C. , Hinton David E. , Rowlands Dewi K. , Chan Chi-On , Mok Daniel K.W. , Largaespada David A. , Warner Nadia , Keng Vincent W.
Published: March 2024

Abstract
Chronic hepatitis B viral (HBV) infection remains a high underlying cause for hepatocellular carcinoma (HCC) worldwide, while the genetic mechanisms behind this remain unclear. This study elucidated the mechanisms contributing to tumor development induced by the HBV X (HBx) gene of predominantly Asian genotype B HBV and its common HBx variants. To compare the potential tumorigenic effects of K130M/V131I (Mut) and wild-type (WT) HBx on HCC, the Sleeping Beauty (SB) transposon system was used to deliver HBx Mut and WT into the livers of fumarylacetoacetate hydrolase (Fah)-deficient mice and in the context of transformation related protein 53 (Trp53) deficiency. From our results, HBx Mut had a stronger tumorigenic effect than its WT variant. Also, inflammation, necrosis, and fibrosis were evident in HBx experimental animals. Reduction of forkhead box O1 (FOXO1) with increased phosphorylation of upstream serine/threonine kinase (AKT) was detected under HBx Mut overexpression. Thus, it is proposed that HBx Mut enhances disease progression by reducing FOXO1 via phosphorylation of AKT. At the metabolomic level, HBx altered the expression of genes that participated in arachidonic acid (AA) metabolism, as a result of inflammation via accumulation of proinflammatory factors such as prostaglandins and leukotriene in liver. Taken together, the increased rate of HCC observed in chronic hepatitis B patients with K130M/V131I-mutated X protein, may be due to changes in AA metabolism and AKT/FOXO1 signaling.
Implications:
Our findings suggested that HBx-K130M/V131I–mutant variant promoted HCC progression by activating AKT/FOXO1 pathway and inducing stronger inflammation in liver via AA metabolism.
Data from Autophagic Flux Is Regulated by Interaction Between the C-terminal Domain of PATCHED1 and ATG101
Authors: Chen Xiaole , Morales-Alcala Cintli C. , Riobo-Del Galdo Natalia A.
Published: March 2024

Abstract
The Hedgehog (Hh) receptor Patched1 (PTCH1) is a well-known tumor suppressor that in its active form represses Smoothened (SMO) activity, inhibits proliferation, and induces apoptosis. The cytoplasmic C-terminal domain (CTD) regulates PTCH1 turnover and nucleates a proapoptotic complex. In this study, it was mechanistically determined that Autophagy-related 101 (ATG101), essential for mammalian autophagy, physically interacts with the CTD of PTCH1 and connects it to the ULK complex, which stimulates the autophagy machinery in response to changes in nutrient availability. This interaction results in a blockade of basal autophagic flux and accumulation of autophagosomes with undegraded cargo. Remarkably, this function of PTCH1 is independent of its repressive activity on SMO, as shown in SMO-deficient cells or in the presence of a SMO inhibitor, but is opposed by Sonic Hedgehog (SHH). These findings reveal a novel noncanonical function of PTCH1 that limits autophagy, mediated by ATG101, which could have therapeutic implications in Hh-dependent cancers.

Implications: Loss-of-function of the tumor suppressor Patched1 might promote cancer cell fitness by increasing autophagic flux in response to metabolic or environmental stresses. Mol Cancer Res; 16(5); 909–19. ©2018 AACR.
Data from Discovery and Characterization of Recurrent, Targetable ALK Fusions in Leiomyosarcoma
Authors: Davis Lara E. , Nusser Kevin D. , Przybyl Joanna , Pittsenbarger Janét , Hofmann Nicolle E. , Varma Sushama , Vennam Sujay , Debiec-Rychter Maria , van de Rijn Matt , Davare Monika A.
Published: March 2024

Abstract
Soft-tissue sarcomas such as leiomyosarcoma pose a clinical challenge because systemic treatment options show only modest therapeutic benefit. Discovery and validation of targetable vulnerabilities is essential. To discover putative kinase fusions, we analyzed existing transcriptomic data from leiomyosarcoma clinical samples. Potentially oncogenic ALK rearrangements were confirmed by application of multiple RNA-sequencing fusion detection algorithms and FISH. We functionally validated the oncogenic potential and targetability of discovered kinase fusions through biochemical, cell-based (Ba/F3, NIH3T3, and murine smooth muscle cell) and in vivo tumor modeling approaches. We identified ALK rearrangements in 9 of 377 (2.4%) patients with leiomyosarcoma, including a novel KANK2-ALK fusion and a recurrent ACTG2-ALK fusion. Functional characterization of the novel ALK fusion, KANK2-ALK, demonstrates it is a dominant oncogene in Ba/F3 or NIH3T3 model systems, and has tumorigenic potential when introduced into smooth muscle cells. Oral monotherapy with targeted ALK kinase inhibitor lorlatinib significantly inhibits tumor growth and prolongs survival in a murine model of KANK2-ALK leiomyosarcoma. These results provide the first functional validation of a targetable oncogenic kinase fusion as a driver in a subset of leiomyosarcomas. Overall, these findings suggest that some soft-tissue sarcomas may harbor previously unknown kinase gene translocations, and their discovery may propel new therapeutic strategies in this treatment-refractory cancer.
Implications:
A subset of leiomyosarcomas harbor previously unrecognized oncogenic ALK fusions that are highly responsive to ALK inhibitors and thus these data emphasize the importance of detailed genomic investigations of leiomyosarcoma tumors.