Integration of Ethanol and the Immune Modulator Curcumin for Immunoablation of Hepatocellular Carcinoma

To investigate immuno-ethanol ablation using an ethanol and immune adjuvant formulation as a potent immunoablation approach that can achieve an enhanced anticancer effect in the treatment of hepatocellular carcinoma (HCC).

Ethanol concentration- and exposure time-dependent cellular responses were investigated. Curcumin was combined with ethanol as an immunoablation agent. Cellular uptake of curcumin, cancer cell killing, and inflammatory markers of ethanol-curcumin treatment were characterized. To evaluate the potential in vivo anticancer immunity of ethanol-curcumin treatment, each right and left lobe of rat liver was concurrently inoculated with N1S1 HCC cells and a mixture of treated N1S1 cells (ethanol only or ethanol-curcumin) in Sprague Dawley rats (each group: 5 rats; control: nontreated N1S1 cells). Tumor growth and immune response were characterized with 7T magnetic resonance (MR) imaging, flow cytometry analysis, and immunohistology.

An optimized ethanol-curcumin (10% ethanol and 0.5% weight/volume (w/v) curcumin solution) treatment contributed to an enhanced cellular uptake of curcumin, increased cancer cell killing, and decreased inflammatory reaction. Ethanol-curcumin-treated N1S1 cell implantation in the rat liver demonstrated N1S1 HCC tumor rejection. The secondary tumor growth by nontreated N1S1 cell inoculation was significantly suppressed at the same time. Activated anticancer immunity was evidenced by significantly increased CD8⁺ T cell infiltration (3.5-fold) and CD8⁺-to-regulatory T cell ratio (4.5-fold) in the experimental group compared with those in the control group.

Enhanced anticancer effect of immuno-ethanol ablation could be achieved with ethanol-curcumin agent. The results underscore the importance of optimized immunoablation therapeutic procedures for enhanced therapeutic outcomes.