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Carbajal, B.

Publications and source records attributed to Carbajal, B..

2 recordsLinked to original sources

Hyperactivated YAP1 Drives an Invasive EMT Subtype of Cervical Squamous Cell Carcinoma

Cervical cancer (CVC) is classically understood as an HPV-driven disease in which high-risk HPV infects cervical basal epithelial cells, induces neoplastic transformation, and drives upward epithelial expansion, pathogenic events underlying the success of cytology- and HPV-based screening. With widespread HPV vaccination and screening, the WHO has launched the CVC elimination initiative and believes that CVC will be the first cancer that would be eliminated as a public health problem. However, statistics showed that CVC remains the most common gynecologic malignancy worldwide, and in the United States, where HPV testing and Pap smears have reached near-maximal implementation, the CVC mortality rate has plateaued for more than two decades. These epidemiologic trends suggest the existence of a subset of CVC that can escape current screening strategies. Here, we demonstrate that hyperactivation of YAP1 caused by disruption of Hippo-YAP signaling is sufficient to induce a subtype of HPV-independent invasive CVC that lacks surface lesions and therefore evades HPV- and cytology-based detection. Using single-cell RNA sequencing combined with high-resolution spatial transcriptomics, we define the cellular architecture, molecular pathways, and immune microenvironment underlying this invasive subtype. We show that YAP1-driven tumors adopt an EMT-high transcriptional state and selectively recruit immunosuppressive myeloid-derived suppressor cells that functionally interact with cancer cells to promote invasion and progression. Our findings suggest that targeting the disrupted Hippo signaling may offer a new strategy to prevent the subset of invasive CVC that current HPV- and Pap-based programs cannot detect, an essential step toward achieving global CVC elimination.

cancer biology↗

Rete Ovarii Epithelial Cells as an Unappreciated Cell of Origin for Pelvic and Ovarian High-Grade Serous Carcinoma

Over the past two decades, converging clinicopathologic, molecular, and evolutionary evidence has established that pelvic and ovarian high-grade serous carcinoma (HGSC) originates predominantly from tubal-type epithelia rather than the ovarian surface epithelium. Consequently, Fallopian tube secretory epithelial cells are widely recognized as the principal cell of origin for HGSC. However, the female reproductive tract contains additional tubular epithelial networks whose potential contributions to HGSC pathogenesis remain unexplored. Here, we identify the rete ovarii (RO), a complex network of intra- and extra-ovarian tubules located within the ovarian hilus and mesovarium, as an alternative candidate tissue of origin for HGSC. We demonstrate that genetic and genomic alterations in rete ovarii epithelial cells (ROECs) can drive their malignant transformation, giving rise to tumors that closely recapitulate the histologic and molecular characteristics of human HGSC. Spatially resolved single-cell transcriptomic analyses of tumors derived from Brca/Trp53/Pten-deficient ROECs (BTP-RO) reveal distinct invasive and immunosuppressive molecular programs. These findings establish ROECs as a previously unrecognized cell of origin for HGSC, expanding the landscape of potential precursor populations beyond the Fallopian tube. The RO-based HGSC model provides a powerful framework for developing origin-informed prevention strategies, early detection approaches, and targeted therapeutics.

cancer biology↗