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Biology subjects

Ariyan, L. A.

Publications and source records attributed to Ariyan, L. A..

2 recordsLinked to original sources

Mena (ENAH) Promotes KRAS-Driven Tumor Growth and Metastatic Progression in Pancreatic Ductal Adenocarcinoma

Metastatic pancreatic ductal adenocarcinoma (PDAC) remains incurable and is projected to become the second leading cause of cancer-related death by 2030. Despite therapeutic advances, median survival remains under one year. Activating KRAS mutations drive the majority of PDAC and underlie their highly aggressive behavior. Although emerging KRAS inhibitors show promise, resistance limits their clinical efficacy, underscoring the need to identify additional regulators of mutant KRAS signaling. We investigated the role of the actin-regulatory protein Mena (ENAH) in KRASG12D-driven PDAC using novel in vitro and orthotopic in vivo models with Mena overexpression and knockdown. Mena overexpression markedly increased primary tumor growth and spontaneous liver metastasis, whereas Mena knockdown delayed tumor onset and reduced metastatic burden. Mechanistically, Mena depletion significantly decreased AKT and ERK activity downstream of KRAS in a SHIP2-mediated manner, indicating that Mena enhances oncogenic signaling required for PDAC progression. These findings reveal Mena as a critical modulator of KRASG12D-driven pancreatic tumor growth and metastasis. By promoting key survival and proliferation pathways, Mena contributes to the aggressive phenotype characteristic of KRAS-mutant PDAC and represents a promising therapeutic target for patients with both locoregional and metastatic disease.

cancer biology↗

TMEM Doorway Mediated Metastasis in Pancreatic Ductal Adenocarcinoma by Tie2 Signaling

Pancreatic ductal adenocarcinoma (PDAC) is almost invariably fatal due to early hematogenous dissemination that occurs before the primary tumor is clinically detectable, yet the cellular mechanism of tumor cell intravasation has remained unknown. Using multiphoton intravital imaging in autochthonous and orthotopic PDAC models, we demonstrate that intravasation occurs at Tumor Microenvironment of Metastasis (TMEM) doorways--tri-cellular structures comprising a MENA-expressing tumor cell, a Tie2 macrophage, and an endothelial cell in direct contact. These structures are abundant in human PDAC, enriched for Tie2 macrophages, and markedly reduced after neoadjuvant chemotherapy. Selective pharmacologic inhibition of Tie2 with rebastinib decreases TMEM-associated transient vascular openings, suppresses circulating and hepatic disseminated tumor cells, and--when combined with perioperative FOLFIRINOX after curative-intent resection--improves median survival in murine PDAC. These findings establish TMEM doorways as a common, druggable mechanism of intravasation across epithelial cancers and identify Tie2 macrophages as a therapeutic target to prevent metastatic seeding in PDAC, a disease with no anti-metastatic therapies. TMEM doorway-mediated intravasation in PDAC supports its role as a common gateway for hematogenous metastasis in carcinoma.

cancer biology↗