Tumor immunogenicity, nutritional repletion, and cancer.

Nutritional repletion in cancer reverses malnutrition and its associated immunodepression, but whether it benefits the host-tumor outcome has been variable. This study hypothesizes that such nutritional support will only favor that host generating a potent antitumor immune response. Murine neuroblastoma (NB) was characterized into immunizing C1300-NB and nonimmunizing TBJ-NB cell lines; and 100 6-week-old strain A mice were assigned on day -14 to isocaloric dietary groups (24% or 2.5% protein). At day 0, mice received either C1300-NB or TBJ-NB; on day 7 one half of the 2.5% group mice were repleted with 24% protein; on day 21, tumor weight/carcass weight (T/C) and mortality (M) were noted. Body weight increased 12.8% in the 24% group and fell 11.4% in the 2.5% group (p less than 0.01). The T/C ratios were smaller for immunogenic C1300-NB on 24% protein compared with 2.5% chow (0.0033 versus 0.0229; p less than 0.02). Repletion produced smaller tumors in the C1300-NB host; strikingly, repletion of TBJ-NB mice significantly increased tumor burden (T/C = 0.0186 versus 0.1657, p less than 0.01) and also increased animal mortality (M = 20% to 30%, p = NS). These data suggest that the influence of nutritional repletion on the tumor-bearing host varies specifically with the presence of an antitumor immune response.