Mechanism of Curcumol Targeting the OTUB1/TGFBI Ubiquitination Pathway in the Inhibition of Angiogenesis in Colon Cancer.

Tumor angiogenesis and metastasis are critical processes in the progression of colon carcinoma. Curcumol, a bioactive sesquiterpenoid derived from curcuma, exhibits anti-angiogenic properties, though its underlying mechanisms remain unclear. In this study, an HT-29 xenograft mouse model demonstrated that curcumol combined with oxaliplatin significantly suppressed tumor growth (Ki67↓) and microvessel density (CD31↓). In vitro assays revealed that curcumol dose dependently inhibited proliferation (MTT), migration (Transwell), and tube formation (CAM assay) in Caco-2/HT-29 and HUVEC cells. Mechanistically, curcumol downregulated OTUB1 expression, promoting TGFB1 degradation via the ubiquitin-proteasome pathway. OTUB1 overexpression activated the TGFB1/VEGF axis, enhancing cell invasiveness and angiogenesis-effects reversed by high-dose curcumol. These findings identify the OTUB1-TGFB1/VEGF axis as a key target of curcumol in inhibiting colon cancer angiogenesis, elucidating its anti-tumor mechanism and offering a novel therapeutic strategy for targeted treatment.