M.W. Roomi, N.W. Roomi, V. Ivanov. M. Rath and A. Niedzwiecki
Dr. Rath Research Institute, Oncology Division, 1260 Memorex Drive, Santa Clara, CA

Presented at: 
The 47th Annual Meeting of the Society of Toxicology; Seattle, Washington; March 16-18, 2008

Published in: 
The Toxicologists (suppl Toxicological Sciences), abstract #874, 2008

Abstract

Introduction: 
Oral cancer represents about 3% of all cancers. The American Cancer Society estimates that approximately 30,000 new cases of oral cancer are diagnosed annually in USA with about 20,000 cases occurring in men and 10,000 in women. Although the exact cause of tongue cancer remains unknown, it is associated with tobacco product use: cigarettes, cigars, pipes and smokeless tobacco. Treatment of tongue cancer is based on the stage of the disease and involves radiation, chemotherapy and surgery. Nutrient supplementation has been reported to support recovery from cancer and maintenance of good health.

Objective: 
We investigated the effect of a novel nutrient mixture (NM) containing lysine, proline, ascorbic acid and green tea extract on human tongue cancer cell line SC-255 in vitro evaluating viability, MMP secretion, invasion and morphology.

Methods and Materials: 
Tongue cancer cell line SC-255 (ATCC) was grown in modified Dulbecco Eagles medium with 10% fetal bovine serum and antibiotics and treated with NM at 0, 10, 50, 100, 500 and 1000 µg/ml in triplicate at each dose. Cells were also treated with PMA (200 ng/ml) for MMP-9 induction. Cell proliferation was assayed by MTT, MMPs by zymography, invasion through Matrigel, and morphology by H&E staining.

Results: 
Zymography demonstrated two bands corresponding to MMP-2 and MMP-9. PMA treatment enhanced MMP-9 secretion. NM inhibited the secretion of both MMP-2 and MMP-9 in a dose dependent fashion, with total virtual inhibition at 500 µg/ml. Invasion through Matrigel was inhibited by 40%, 80% and 100% at 100, 500 and 1000 µg/ml NM respectively. NM was not toxic to SC-255 tongue cancer cell line at 100 µg, but exhibited 20 % and 30% toxicity at 500 and 1000 µg/ml. H&E staining showed slight changes at the highest concentration.

Conclusions:
NM significantly inhibited MMP secretion, invasion through Matrigel and growth, important parameters for cancer prevention, suggesting NM has potential for therapeutic use in treatment of tongue cancer.

Comments

Oral cancer represents about 3% of all cancers, with an estimated annual occurrence in the USA of approximately 20,000 cases in men and 10,000 in women. Extracellular matrix (ECM) matrix metalloproteinases (MMPs) produced by tumor and stromal cells play a key role in tumor invasion and metastasis. The nutrient mixture (NM) containing lysine, proline, ascorbic acid and green tea extract significantly inhibited MMP-2 and MMP-9 secretion and invasion by human tongue cancer cells through Matrigel, suggesting NM has potential for therapeutic use in treatment of tongue cancer.