An Oncolytic Vaccinia Virus Expressing Aphrocallistes Vastus Lectin Modulates Hepatocellular Carcinoma Metabolism via ACSS2/TFEB-Mediated Autophagy and Lipid Accumulation.

Abstract

Hepatocellular carcinoma (HCC) remains a therapeutic challenge due to metabolic plasticity and drug resistance. Oncolytic viruses (OVs), such as thymidine kinase-deleted vaccinia virus (oncoVV), selectively lyse tumors while stimulating antitumor immunity, however, their metabolic interplay with cancer cells is poorly understood. Here, we engineered an oncoVV-expressing Aphrocallistes vastus lectin (oncoVV-AVL) and uncovered its unique ability to exploit the ACSS2/TFEB axis, driving metabolic competition in HCC. In vitro, oncoVV-AVL triggered cell autophagy and lipid accumulation (3.4-5.7-fold upregulation of FASN and ACC1) while suppressing glucose uptake (41-63% higher extracellular glucose and 33-34% reduced lactate). Mechanistically, oncoVV-AVL upregulated acetyl-CoA synthetase 2 (ACSS2), promoting its nuclear translocation and interaction with transcription factor EB (TFEB) to concurrently activate lipogenesis and autophagic flux. The pharmacological inhibition of ACSS2 abolished these effects, confirming its central role. In vivo, oncoVV-AVL suppressed tumor growth while inducing lipid deposition (2-fold triglyceride increase), systemic hypoglycemia (42% glucose reduction), and autophagy activation (elevated LC3B-II/I ratios). This study establishes ACSS2 as a metabolic checkpoint in OV therapy, providing a rationale for combining oncolytic virotherapy with metabolic modulators in HCC.