Angela Jun

Chemotherapy-induced mucositis (CIM) is a dose-limiting toxicity of cancer therapy that is mainly associated with mitochondrial dysfunction in epithelial cells. We investigated whether GV1001, a mitochondrial protective peptide from human telomerase reverse transcriptase (hTERT), attenuates 5-fluorouracil (5-FU)-induced mucositis in a murine model. 5-FU induced notable mortality, leukopenia, and mucositis in the gastrointestinal (GI) tract, including tongue, esophagus and small intestine. It promoted epithelial–mesenchymal transition (EMT), nuclear factor kappa-B (NF-κB) activation, systemic and mucosal inflammation, DNA damage, impaired cell proliferation, and apoptosis throughout the GI tract. GV1001 blocked 5-FU–associated mortality, significantly attenuated leukopenia, and notably prevented mucositis. GV1001 also suppressed 5-FU-induced DNA damage, EMT, loss of proliferative capacity, apoptosis, and NF-κB activation in mucosal epithelium. In normal human keratinocytes, 5-FU inhibited the cell proliferation, disrupted mitochondrial function, as evidenced by reduced mitochondrial membrane potential, increased reactive oxygen species (ROS) production, impaired electron transport chain (ETC) complex integrity, decreased ATP synthesis, and cytochrome c release into the cytosol. GV1001 markedly mitigated these 5-FU-induced mitochondrial defects. Taken together, GV1001 mitigates CIM by most likely preserving mitochondrial integrity and function, supporting its potential as a strategy to prevent cancer chemotherapy-associated mucosal injury in patients.

Cluster of Differentiation 47 (CD47) functions as a key “don’t-eat-me” signal that enables cancer cells to evade macrophage-mediated immune clearance. GV1001, a 16-amino-acid peptide derived from human telomerase reverse transcriptase (hTERT), has been reported to exhibit antitumor and anti-inflammatory properties and to downregulate CD47 expression in human cells. In this study, we investigated whether GV1001 modulated CD47 expression and enhanced antitumor immunity in oral squamous cell carcinoma (OSCC). In vitro, GV1001 significantly reduced CD47 expression in both murine and human OSCC cells in dose- and time-dependent manners, resulting in a marked increase in macrophage-mediated phagocytosis. Mechanistically, GV1001 suppressed CD47 promoter activity and inhibited multiple upstream regulator expression in murine and human OSCC cell lines, while exerting minimal effects on normal human keratinocytes and fibroblasts. In vivo, GV1001 significantly inhibited tumor growth, suppressed CD47 expression, increased macrophage infiltration, and induced tumor cell necrosis and apoptosis in both murine OSCC syngeneic graft model and human OSCC xenograft model. GV1001 administered alone or in combination with cisplatin produced antitumor effects. Collectively, these findings demonstrate that GV1001 functions as a potent immunomodulatory anticancer peptide that downregulates CD47 expression and restores macrophage-mediated tumor clearance, highlighting its potential as a therapeutic strategy for OSCC.