Linoleic Acid Reduces Paclitaxel Chemosensitivity in Colorectal Cancer.

PURPOSE: Paclitaxel, a natural diterpenoid compound derived from Taxus species, is one of the most successful plant-based anticancer drugs and has been widely applied in the treatment of various solid tumors. In recent years, emerging evidence has suggested its potential efficacy in refractory or advanced colorectal cancer (CRC), particularly in patients resistant to standard first-line chemotherapy such as 5-fluorouracil (5-FU). However, responses to paclitaxel in CRC are heterogeneous. This study aimed to elucidate the metabolic determinants underlying the heterogeneous response of CRC to paclitaxel and to identify serum metabolites associated with therapeutic response.

PATIENTS AND METHODS: Integrated serum metabolomic profiling was performed in patient-derived tumor organoid (PDTOs, n=18), combined with drug sensitivity assays and in vivo validation using mouse xenograft models. An analysis was conducted to sensitivity of paclitaxel, followed by targeted metabolomic quantification and pathway enrichment to identify key metabolites influencing paclitaxel efficacy.

RESULTS: Linoleic acid (LA) was identified as a serum metabolite significantly correlated with reduced paclitaxel sensitivity. Elevated LA levels attenuated paclitaxel-induced G2/M cell cycle arrest and reduced cytotoxicity by altering microtubule dynamics. Functional validation in CRC cell lines and animal models further confirmed that LA diminished the antitumor effect of paclitaxel, supporting a metabolism-mediated mechanism of chemoresistance.

CONCLUSION: This study identifies serum linoleic acid as a metabolism-related candidate biomarker associated with paclitaxel resistance in CRC. These findings highlight the potential clinical relevance of metabolic factors in modulating chemotherapy response and suggest that LA may have potential relevance for patient stratification in future studies of paclitaxel response in CRC.