Biology subjects

Beronja, S.

Publications and source records attributed to Beronja, S..

3 recordsLinked to original sources

bioRxiv2026

Dysregulation of epithelial differentiation architecture underlies field cancerization in head and neck cancer

Head and neck squamous cell carcinoma (HNSCC) has exceptionally high recurrence rates, exceeding 50%, contributing to mortality and morbidity. This recurrence rate is proposed to be due to field cancerization, a phenomenon where tumor-adjacent "field" tissue that appears histologically normal harbors molecular changes that prime it for subsequent tumor growth. Current models attribute field cancerization to shared driver mutations between tumors and adjacent at-risk tissue, but this assumption has never been directly tested. To comprehensively characterize this phenomenon, we profiled patient-matched tumor, normal-adjacent field (NAF), contralateral normal, and blood samples from HPV-negative HNSCC patients using whole genome sequencing, targeted driver gene sequencing, single-nucleus multiome profiling, spatial transcriptomics and functional proliferation assays. While histologically normal NAF tissues did harbor expanded mutant clones, these mutations rarely overlapped with paired tumors and were not shared across patients, suggesting molecular features beyond mutations are altered in NAF. Single-cell multiomics revealed that NAF epithelium loses its normal organizational hierarchy: basal stem cell markers persist in differentiated cells, while terminal differentiation programs fail to activate, with reconfiguration of both gene regulatory networks and cell-cell interactions. Proliferating cells appeared in tissue layers normally restricted to post-mitotic cells, a pattern typically seen only in overt dysplasia. Within this disrupted hierarchy, a distinct epithelial state arose in NAF that expressed both normal epithelial and tumor-associated markers, which we localized to the parabasal layers using immunofluorescence and spatial transcriptomics. Together, our findings demonstrate that field cancerization operates through epithelial hierarchy disorganization that disrupts differentiation, generates cells with tumor-like features, and may create a permissive environment for the expansion of cancer-associated mutations, all within tissue that appears histologically normal.

cancer biology↗

bioRxiv2025

Subtype-Specific Dependencies and Drug Vulnerabilities Enable Precision Therapeutics in Head and Neck Cancer

Molecular heterogeneity in head and neck squamous cell carcinoma (HNSCC) is well recognized, yet existing subtype frameworks remain largely descriptive and have not translated into therapeutic decision-making. Here, we establish a mechanistic platform that converts transcriptomic diversity into drug-actionable tumor states. Integrating multi-cohort RNA-seq from 727 tumors across five independent datasets, genome-scale CRISPR dependency maps, and pharmacologic screening, we define distinct tumor survival circuits across HPV-negative HNSCC and nominate subtype-matched therapeutic strategies. These circuits encompass a proliferative axis (MYC, MET/FAK, inflammatory and translational programs), an epithelial-differentiated/adhesion program, an EMT-like state with stromal activation, and mitochondrial/oxidative metabolic states, each mapping to selective liabilities (e.g., mitotic/autophagy control, ERBB/PI3K and cadherin signaling, OXPHOS/mitochondrial translation, and G2/M-integrin-Notch pathways, respectively). We then develop a transcriptomic predictor of EGFR-inhibitor response using machine learning and validate it in prospectively collected, fresh patient-derived 3D microtumors. The resulting 13-gene signature identifies erlotinib-responsive tumors (R = 0.93) and maps biologically to an epithelial-differentiated state, outperforming EGFR expression alone. Our study establishes a subtype-to-dependency-to-therapy framework, enabling precision stratification and providing a clinically feasible path for prospective biomarker deployment.

bioinformatics↗

bioRxiv2021

SOX2-phosphorylation toggles a bistable differentiation-switch in squamous cell carcinoma

The fate choice between stem cell self-renewal and differentiation is regulated by bistable transcriptional networks, which are balanced in homeostasis and imbalanced in tumors. Yet, how stem cells switch from self-renewal to differentiation remains a conundrum. Here, we discover a molecular mechanism that allows stem cell-like tumor propagating cells (TPCs) in squamous cell carcinomas (SCCs) to switch from a mutually exclusive SOX2-PITX1-TP63 self-renewal circuit to a KLF4 driven differentiation program, dependent on the relative occupancy of a novel Klf4-regulatory enhancer cluster (Klf4EC944) by SOX2 or KLF4, respectively. We find SOX2 occupies this site in TPCs to inhibit Klf4 transcription, but upon phosphorylation SOX2 becomes evicted from Klf4EC944, allowing residual KLF4 to occupy this site instead, boost the expression of KLF4 and its downstream targets, and differentiate self-renewing TPCs into post-mitotic SCC cells. This mechanism allows SOX2 to promote self-renewal and tumor formation, while preserving the differentiation potential in SCC cells. Our data suggest that stochastic cell fate decisions depend on the effective concentration of enzymatically regulated transcription factors. The surprising specificity by which SOX2-phosphorylation governs the bistable Klf4EC944 network-switch in SCCs reveals a conceptual framework for the identification of similar switches in other stem cell and cancer types and their potential development into cell type specific differentiation therapies for diseases in which tissue homeostasis has gone awry.

cancer biology↗