I just read a report from Nagoya City University Medical School in Japan and wonder if anyone knows anything about cimetidine. Their findings state:

Our observations support the previous clinical findings that cimetidine increased the survival of cancer patients. It is likely that cimetidine may block cancer cell adhesion to endothelial cells and thus prevent metastasis. In fact, we found in our recent randomized clinical study that cimetidine treatment significantly reduced cancer metastasis and recurrence, thus resulting in the prolonged survival of patients with colorectal cancer.

Annie..There may be something to this. Cimetidine(brand name Tagamet) is classified as an H2 antagonist. This blocks production of stomach acid. You can buy it at drug stores, supermarkets, discount stores etc. It was one of the first effective anti-ulcer drugs in its class. I have seen physicians prescribe cimetidine in high doses to cure common warts. Thus it may indeed have something to do with immunity and cancer prevention.
Positive4U :)