In contrast to cohort one, total tumor mass was greater among the mice with 4T1 tumors relative to the 67NR tumors (Fig. 6B, p < 0.001, unpaired t-test) in this study; however, as reported for cohort one, mice with 4T1 tumors had significantly greater spleen mass (Fig. 6C, p < 0.05, Dunn’s multiple comparisons) and hippocampal IL-1β concentration (Fig. 6D, p < 0.05, Dunn’s multiple comparisons) than mice with 67NR tumors. This evidence concerns the gene IL1B and neoplasm.