Biomedical subjects
Publications and source records attributed to E H Hwang.
The incidence of carcinoma of the large bowel is very low in children, and it is also known that the prognosis of this tumour in children is very poor. Recently the authors experienced a case of adenocarcinoma of the transverse colon in a 12 year old boy who survived more than 6 years without evidence of disease. This particular case is reported here with a review of the literature.
Stage IV-S neuroblastoma, characterized by a primary tumor plus disseminated tumors in liver, skin and bone marrow, has a favorable clinical prognosis when compared to metastatic Stage IV neuroblastoma. This favorable outcome also characterized mice receiving tumor transplants to these "IV-S" sites. We report the testing of the hypothesis that enhanced anti-tumor immunity in "IV-S" site neuroblastoma recipients explains this improved survival. A million murine C1300 neuroblastoma cells were inoculated into 256 A/J mice to either "IV-S" sites of skin, liver, peritoneal cavity, or to the disseminated stage "IV" sites of subcutaneous tissue, muscle, kidney and lung. After 21 and 28 days of tumor growth, spleen cells from tumor bearing mice were harvested and analyzed by a 51 Cr release lymphocytotoxicity assay. Cytotoxic T cell activity was consistently higher at day 28 than day 21. In the liver and in the peritoneal cavity, cytotoxic T cell activity was higher than in other organs, and at day 28 these values were significantly higher than Stage "IV" sites. On the other hand, skin is not a immunologically privileged site in vivo study.
Nutritionally supporting the malnourished tumor bearing host may not benefit the disease outcome, but, rather, may preferentially "feed the cancer". We hypothesized that repletion is beneficial only when it augments an anti-tumor immune response. To support this hypothesis, 240 A/J mice were assigned to isocaloric dietary groups (24%, 5%, or 2.5% protein). On day 14 the mice received either immunogenic C1300- neuroblastoma (NB) or non-immunizing TBJ-NB. On day 21 half of the restricted animals were repleted with 24% protein chow. At day 35, chromium-release cell-mediated cytotoxicity was measured. In the group of mice that received 2.5% protein chow, nutritional repletion specifically augmented anti-tumor activity for C1300-NB which elicits a host immune response (33.78 L.U. (repleted) vs 3.47 L.U. (depleted) p less than 0.01), in contrast, nutritional repletion was detrimental for non-immunizing TBJ-NB, where further depression of cytotoxicity was seen (1.37 L.U. (repleted) vs 2.06 L.U. (depleted) 0 less than 0.01). This suggests that the influence of nutritional repletion in tumor nearing animals is dependent on the integrity of host's anti-tumor immunity.