The new target gene is called methylenetetrahydrofolate reductase, or MTHFR. Researchers were able to inhibit the function of the gene by creating antisense--an exact opposite of a tiny section of the MTHFR gene. "MTHFR is involved in the synthesis of methionine--a critical nutrient necessary for growth of cancer cells," explains Dr. Rima Rozen, principal investigator of the new study, and Deputy Scientific Director of the MUHC Research Institute. "By inhibiting the gene's function, we were able to slow the growth of tumors."
Researchers found that the antisense reduced lung and colon cancer tumors in both laboratory-based tissue cultures and in mice. "Discovering that the antisense works in animal models is a major step forward, and gives us hope that this might also work in humans," explains Dr. Rozen.
The research, funded by Strida Pharma--a McGill University spin-off company--also indicated that the antisense was particularly effective in reducing cancer tumors when administered in low doses and in combination with established cancer drugs. "All drugs and antisense have some level of toxicity," says Dr. Rozen. "An antisense that works in harmony with other drugs, and in such low doses, is a significant breakthrough in cancer research."