Abstract No. 156 Immuno-Ethanol Ablation of Hepatocellular Carcinoma

Immuno-ethanol ablation using an ethanol and immune adjuvant formulation is investigated as a potent anti-cancer immuno-ablative approach which can achieve a synergistic anticancer effect in the treatment of hepatocellular carcinoma (HCC). Ethanol concentration- and exposure time-dependent cancer cellular responses were characterized. Water insoluble anti-cancer/anti-inflammatory Curcumin was combined with ethanol as an immuno-ablation agent. Cellular uptake efficiency of Curcumin, cancer cell killing effect, and inflammatory marker changes (STAT3, p65, PD-L1, and GPX-4) of ethanol-curcumin treatment were characterized with confocal fluorescent microscope, CCK8, and Western blot assay. To evaluate the potential in vivo anti-cancer immunity of ethanol-curcumin treatment, the right lobe of rat liver and left lobe of rat liver were simultaneously inoculated N1S1 HCC cells (5 million) and a mixture of treated N1S1 cells (2.5 million, 10% ethanol only or 10% ethanol-curcumin) respectively in Sprague Dawley rats (n=15, each group: 5 rats, control: non-treated N1S1 HCC cell implantation). Tumor growth and immune response of each group were characterized with 7T MRI, flowcytometry analysis, and immunohistology. Ethanol concentration gradient during the ethanol ablation treatment might induce an incomplete cancer cell death and inflammatory markers. Our optimized ethanol-curcumin treatment as a form of immuno-ethanol ablation contributed to an enhanced cellular uptake of Curcumin, increased cancer cell killing, and decreased inflammatory reaction. The ethanol-curcumin treated HCC cell implantation in the rat liver demonstrated anti-cancer immune mediated N1S1 HCC tumor rejection. The secondary tumor growth with simultaneously implanted non-treated N1S1 HCC cells in left lobe was also significantly suppressed with the tumor growth inhibition of ethanol-curcumin treated N1S1 HCC cells (P < 0.05). It indicates a potential anti-cancer immunity mediated abscopal effect of ethanol-curcumin immuno-ablation. Significantly increased CD8 T cell infiltration and CD8/Treg ratio in the experimental group compared to the control confirmed the activated anti-cancer immunity (P < 0.01). Synergistic anti-cancer effect of immuno-ethanol ablation therapy could be achieved with ethanol-curcumin agent. The results underscore the importance of coherent immuno-ablation therapeutic procedures using optimized therapeutic agents for the synergistic therapeutic outcomes.