Metastatic melanoma is known to have poor survival rates. We are learning that a major change in cancer cells is intracellular alkalinization and extracellular acidification, early. The acid environment drives proliferation, invasion and metastasis. The alkaline interior of the cell prevents apoptosis of cancer cells.

A recent approach to cancer treatment is the use of proton pump inhibitors (PPIs,) such as esomeprazole (ESOM.) PPIs are pro-drugs which are stimulated by an acid environment to neutralize the pH inside the cells by inhibiting the removal of protons from them. PPI activity is dependent on extracellular acidity. PPIs reduce multidrug (multi-drug) resistance to cancer chemotherapy. (PPIs have long been used as a treatment for gastric acidity.)

The present study used mice with transplanted melanoma tumors and treated them with ESOM to demonstrate anticancer activity. Metastatic melanoma tumors were even more sensitive to ESOM than were the primary melanoma tumors.

ESOM inhibited melanoma cancer cell proliferation and destroyed cancer cells by apoptosis, especially under acid conditions. ESOM reduced the pH gradient across melanoma cell walls and increased survival of the mice with melanoma cancer. At the 2.5 mg./kg. dosage in mice, ESOM caused a 50% reduction in tumor size.

A human clinical study using ESOM as the only treatment is going on in Italy at this time.

CONCLUSION: PPIs are cytotoxic (toxic to cells) to human melanoma cells by altering the pH gradient across cell wells of the tumor cells. PPIs reduce multidrug resistance. This research was done on mice and has not, yet, been demonstrated in human clinical studies.

NOTE: Evidence is shown that resveratrol, quercitin and cinnamate are therapeutic by their PPI activity in melanoma cells. Read more about the Na/K pump and tumor acidity.

To read the author’s abstract of the article click on the link to the author’s title of the article above.

PMID: 19876915.

Summary #343.