Thermal ablation of a second primary organ (kidney) leads to increased distant subcutaneous R3230 tumor growth that is suppressed with adjuvant nanoparticle anti-IL6 siRNA.

<p><b>(A)</b> Subcutaneous R3230 tumors implanted in Fisher 344 rats with similar growth rates were randomized at Day 0 to one of four different treatment arms (n = 6–7 animals/arm). Thermal ablation of normal kidney alone resulted in significantly greater tumor growth and change in diameter (5d before to 7d after treatment) compared to sham treatment or MNP anti-IL6 siRNA alone (p<0.01 for all comparisons, mean ± standard deviation for all data). MNP anti-IL6 siRNA combined with thermal ablation reduced distant tumor growth rate and endpoint diameter to baseline sham levels. <b>(B)</b> Adjuvant MNP anti-IL6 siRNA combined with kidney thermal ablation also reduced distant tumor proliferation (Ki-67) and microvascular density (CD34) to baseline levels compared to kidney thermal ablation alone (p<0.01 for relevant comparisons). <b>(C)</b> Adjuvant MNP anti-IL6 siRNA suppressed kidney thermal ablation-induced elevations in serum IL-6 levels at 6hr post-treatment (n = 3–4 animals/arm, p = 0.006).