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Biology subjects

Keri, R. A.

Publications and source records attributed to Keri, R. A..

7 recordsLinked to original sources

Integrated Collagen Architecture and Composition Improve Risk Stratification in Triple-Negative Breast Cancer

PurposeTriple-negative breast cancer (TNBC) exhibits substantial clinical heterogeneity, with some patients experiencing early recurrence and poor survival despite similar clinicopathologic features. We sought to determine whether quantitative measures of intratumoral collagen architecture and composition derived from standard histopathologic specimens can identify patients at risk of recurrence and adverse survival outcomes. Experimental DesignWe analyzed a retrospective cohort of 79 TNBC tumors assembled into a tissue microarray using a multimodal computational pathology framework integrating Massons Trichrome staining with COL1 and COL3 immunohistochemistry. Collagen architecture was quantified using fiber-based image analysis and unsupervised clustering, while collagen composition was assessed using a normalized COL3:COL1 ratio. Associations with recurrence-free interval (RFI) and overall survival (OS) were evaluated using Kaplan-Meier analysis, restricted mean survival time (RMST), and Cox proportional hazards modeling. ResultsUnsupervised analysis identified four distinct collagen architectural states, which were consolidated into low-risk and high-risk groups based on recurrence patterns. High-risk collagen architecture was associated with significantly worse long-term RFI (log-rank p=0.025; RMST difference 10.1 months). Independently, a higher COL3:COL1 ratio was associated with improved OS (log-rank p=0.042; RMST difference 9.4 months). Integration of architectural and compositional biomarkers further refined risk stratification, identifying a subgroup with high-risk architecture and low COL3:COL1 ratio that exhibited the poorest survival outcomes. Notably, collagen-based stratification identified patients with divergent outcomes not readily predicted from tumor stage alone. ConclusionsQuantitative assessment of intratumoral collagen architecture and composition provides clinically meaningful prognostic information in TNBC and enables stratification of recurrence and survival risk. These findings support extracellular matrix phenotyping as a practical and scalable computational pathology approach for refining risk assessment in TNBC. Translational RelevanceTriple-negative breast cancer (TNBC) remains clinically challenging due to heterogeneous outcomes that are not fully captured by standard clinicopathologic variables. In this study, we demonstrate that quantitative features of intratumoral collagen architecture and composition, derived from routine pathology specimens, provide clinically meaningful prognostic information. Collagen-based biomarkers, including distinct collagen architectural phenotypes and the COL3:COL1 ratio, identify patient subgroups with distinct recurrence and survival outcomes, particularly among individuals whose risk is not adequately predicted by conventional staging. Importantly, these features can be extracted from widely available histological stains and immunohistochemistry, supporting the potential integration into existing pathology workflows. These findings support the tumor microenvironment as an underutilized source of biomarkers and suggest that extracellular matrix-based phenotyping may improve risk stratification and inform clinical decision-making in TNBC.

cancer biology↗

PML1-Mediated Feedforward Loop Through PI3K and MAPK Axes Drives Endocrine Resistance

Treatment of estrogen receptor-positive (ER+) breast cancer is significantly hindered by endocrine resistance. We identified PML1 as a key therapeutic entity that can be targeted to overcome resistance. Endocrine-resistant breast cancer cells share three key characteristics: elevated PML1 protein levels, enhanced activity of PI3K, MAPK, or both signaling pathways, and reduced ER activity. We developed a PML1 gene signature that predicts poor prognosis and correlates strongly with PI3K, MAPK, and endocrine resistance gene signatures, as evident by cellular studies, scRNA-seq analysis, and spatial transcriptomics of endocrine therapy-treated tumors. This signature is present in endocrine-resistant breast cancer cells harboring the Y537S ER mutation. We consistently demonstrate high PML1 protein levels across cells resistant to various treatments, including 4-hydroxytamoxifen, fulvestrant, elacestrant, and CDK4/6 inhibitors. Furthermore, treatments with these therapeutic agents or knockdown of ESR1 mRNA also increase PML1 protein levels. Mechanistically, we show that ER inhibition through fulvestrant treatment activates PI3K and MAPK signaling, which enhance PML1 protein stability and synthesis. PML1 then drives a feedforward loop by stimulating the expression of cytokine and growth factor mRNAs, including CCL5 and HBEGF, further amplifying PI3K and MAPK signaling. Consequently, in endocrine-resistant cells, endocrine therapies, while inactivating ER, paradoxically reinforce this loop through increased PI3K/MAPK activation and PML1 protein accumulation, ultimately compromising therapeutic efficacy. Finally, we demonstrated that arsenic trioxide, an FDA-approved, PML-reducing drug, effectively disrupts this feedforward loop, offering a promising strategy for treating resistant metastatic breast cancer. STATEMENT OF SIGNIFICANCEEndocrine resistance remains a major obstacle in treating estrogen receptor-positive metastatic breast cancer. Our study identifies PML1 as a central mediator of this resistance, revealing how it maintains a self-reinforcing signaling network through PI3K and MAPK pathways by enhancing the production of cytokines and growth factors. The clinical significance of our findings is threefold: we establish PML1 as a biomarker for therapy resistance, demonstrate its mechanistic role in treatment failure, and show that FDA-approved arsenic trioxide can disrupt PML1-driven resistance. These insights provide a direct path to clinical translation, as combining arsenic trioxide with existing therapies could benefit patients with limited treatment options.

cancer biology↗

Mitoxantrone inhibits and downregulates ERα through binding at the DBD-LBD interface

Targeting the estrogen receptor (ER or ER) through competitive antagonists, receptor downregulators, or estrogen synthesis inhibition remains the primary therapeutic strategy for luminal breast cancer. We have identified a novel mechanism of ER inhibition by targeting the critical interface between its DNA-binding domain (DBD) and ligand-binding domain (LBD). We demonstrate that mitoxantrone (MTO), a topoisomerase II inhibitor, binds at this previously unexplored DBD-LBD interface. Using comprehensive computational, biophysical, biochemical, and cellular analyses, we show that independent of its DNA damage response activity, MTO binding induces distinct conformational changes in ER, leading to its cytoplasmic redistribution and subsequent proteasomal degradation. Notably, MTO effectively inhibits clinically relevant ER mutations (Y537S and D538G) that confer resistance to current endocrine therapies, outperforming fulvestrant in both in vitro and in vivo assays. Our findings establish domain-domain interaction targeting as a viable therapeutic strategy for ER, with translational implications for other nuclear receptors.

cancer biology↗

Alterations in the preneoplastic breast microenvironment of BRCA1/2 mutation carriers revealed by spatial transcriptomics

Breast cancer is the most common cancer in females, affecting one in every eight women and accounting for the majority of cancer-related deaths in women worldwide. Germline mutations in the BRCA1 and BRCA2 genes are significant risk factors for specific subtypes of breast cancer. BRCA1 mutations are associated with basal-like breast cancers, whereas BRCA2 mutations are associated with luminal-like disease. There are currently few chemoprevention strategies available for BRCA1/2 mutation carriers, and irreversible prophylactic mastectomy is the primary option. Designing chemo-preventive strategies requires an in-depth understanding of the physiological processes underlying tumor initiation. Here, we employ spatial transcriptomics to investigate defects in mammary epithelial cell differentiation accompanied by distinct microenvironmental alterations in preneoplastic breast tissues from BRCA1/2 mutation carriers and normal breast tissues from non-carrier controls. We uncovered spatially defined receptor-ligand interactions in these tissues for the investigation of autocrine and paracrine signaling. We discovered that {beta}1-integrin-mediated autocrine signaling in BRCA2-deficient mammary epithelial cells differs from BRCA1-deficient mammary epithelial cells. In addition, we found that the epithelial-to-stromal paracrine signaling in the breast tissues of BRCA1/2 mutation carriers is greater than in control tissues. More integrin-ligand pairs were differentially correlated in BRCA1/2-mutant breast tissues than non-carrier breast tissues with more integrin receptor-expressing stromal cells. These results reveal alterations in the communication between mammary epithelial cells and the microenvironment in BRCA1 and BRCA2 mutation carriers, laying the foundation for designing innovative breast cancer chemo-prevention strategies for high-risk patients.

cancer biology↗

Comprehensive characterization of protein-protein interaction network perturbations by human disease mutations

Technological and computational advances in genomics and interactomics have made it possible to identify rapidly how disease mutations perturb interaction networks within human cells. In this study, we investigate at large-scale the effects of network perturbations caused by disease mutations within the human three-dimensional (3D), structurally-resolved macromolecular interactome. We show that disease-associated germline mutations are significantly enriched in sequences encoding protein-protein interfaces compared to mutations identified in healthy subjects from the 1000 Genomes and ExAC projects; these interface mutations correspond to protein-protein interaction (PPI)-perturbing alleles including p.Ser127Arg in PCSK9 at the PCSK9-LDLR interface. In addition, somatic missense mutations are significantly enriched in PPI interfaces compared to non-interfaces in 10,861 human exomes across 33 cancer subtypes/types from The Cancer Genome Atlas. Using a binomial statistical model, we computationally identified 470 PPIs harboring a statistically significant excess number of missense mutations at protein-protein interfaces (termed putative oncoPPIs) in pan-cancer analysis. We demonstrate that the oncoPPIs, including histone H4 complex in individual cancer types, are highly correlated with patient survival and drug resistance/sensitivity in human cancer cell lines and patient-derived xenografts. We experimentally validate the network effects of 13 oncoPPIs using a systematic binary interaction assay. We further showed that ALOX5 p.Met146Lys at the ALOX5-MAD1L1 interface and RXRA p.Ser427Phe at the RXRA-PPARG interface promote significant tumor cell growth using cell line-based functional assays, providing a functional proof-of-concept. In summary, if broadly applied, this human 3D interactome network analysis offers a powerful tool for prioritizing alleles with mutations altering PPIs that may contribute to the pathobiology of human diseases, and may offer disease-specific targets for genotype-informed therapeutic discovery.

systems biology↗

JAM-A functions as a female microglial tumor suppressor in glioblastoma

Glioblastoma (GBM) remains refractory to treatment. In addition to its cellular and molecular heterogeneity, epidemiological studies indicate the presence of additional complexity associated with biological sex. GBM is more prevalent and aggressive in male compared to female patients, suggesting the existence of sex-specific growth, invasion, and therapeutic resistance mechanisms. While sex-specific molecular mechanisms have been reported at a tumor cell-intrinsic level, sex-specific differences in the tumor microenvironment have not been investigated. Using transgenic mouse models, we demonstrate that deficiency of junctional adhesion molecule-A (JAM-A) in female mice enhances microglia activation, GBM cell proliferation, and tumor growth. Mechanistically, JAM-A suppresses anti-inflammatory/pro-tumorigenic gene activation via interferon-activated gene 202b (Ifi202b) and found in inflammatory zone (Fizz1) in female microglia. Our findings suggest that cell adhesion mechanisms function to suppress pathogenic microglial activation in the female tumor microenvironment, which highlights an emerging role for sex differences in the GBM microenvironment and suggests that sex differences extend beyond previously reported tumor cell intrinsic differences.\n\nSummaryTuraga et al. demonstrate that female microglia drive a more aggressive glioblastoma phenotype in the context of JAM-A deficiency. These findings highlight a sex-specific role for JAM-A and represent the first evidence of sexual dimorphism in the glioblastoma microenvironment.

cancer biology↗

ITGA2 is a target of miR-206 promoting cancer stemness and lung metastasis through enhanced ACLY and CCND1 expression in triple negative breast cancer

Accumulating evidence demonstrates that cancer stemness is essential for both tumor development and progression, regulated by multi-layer factors at genetic, epigenetic and micro-environmental levels. However, how to target stemness-driven plasticity and eliminate metastasis remains one of the biggest challenges in the clinic. We aim to identify novel molecular mechanisms underlying stemness of triple negative breast cancer (TNBC) which frequently metastasizes to the visceral organs but lacks targeted therapies. Following our previous discovery of miR-206 as an epigenetic suppressor of tumorigenesis and metastasis, we now report that the integrin receptor CD49b-encoding ITGA2 is an oncogenic target of miR-206 in TNBC. ITGA2 knockdown abolished cancer stemness (mammosphere formation, pluripotency marker expression, and FAK phosphorylation), inhibited cell cycling, compromised migration and invasion, and thereby decreasing lung metastasis of TNBC. RNA sequencing analyses of breast cancer cells revealed that ITGA2 knockdown inhibits gene expression essential for both classical integrin-regulated pathways (cell cycle, wounding response, protein kinase, etc) and newly identified pathways such as lipid metabolism. Notably, ACLY-encoded ATP citrate lyase is one of the top targets in CD49b-regulated lipid metabolism and CCND1-encoded Cyclin D1 represents regulation of cell cycle and many other pathways. ACLY, known to catalyze the formation of cytosolic acetyl-CoA for fatty acid biosynthesis, is indispensable for cancer stemness. Overexpression of CCND1 rescues the phenotype of ITGA2 knockdown-induced cell cycle arrest. High expression levels of the ITGA2/ACLY/CCND1 axis are correlated with an unfavorable relapse-free survival of patients with high grade breast cancer, in both basal-like and other subtypes. This study identifies ITGA2 as a potential therapeutic target of TNBC stemness and metastasis.

cancer biology↗