PDCD1 and neoplasm: The niclosamide or anti-PD-1 antibody treatment inhibited tumor growth and supplementary animal survival, but the mice receiving niclosamide plus anti-PD-1 antibody combination treatment showed a more significant tumor growth delay (Fig. 4i) and significantly better overall survival (Fig. 4j), compared with that of either treatment alone (p < 0.001, n = 10).