Question

Do you think the treatment strategies that inhibit telomerase would be effective in treating cancer? How does the cancer stem cell hypothesis complicate or compliment these strategies? Please explain

Answer 1

Telomeres are non-coding sequence of DNA essential for growth and replication of the eukaryotic cells. Based on the length of the telomeres in the chromosomes, aging and replication of the cells are controlled. Telomerase are the enzymes help during the replication process to add the telomeres sequence in the chromosomes. When the addition of telomeres in the DNA sequence is not controlled by these telomerase enzyme then the problem of overproduction of cells arises, which leads to cancer.

Targeting these telomerase enzymes could be a potential anti-cancer treatment. When the telomerase enzymes are inhibited during the cell cycle leads to shortening of telomere in the cancer cells resulting in the cell death. But targeting these enzymes, in most cells, does not have an immediate effect on cell replication. Only shortening of telomeres to a critical length after multiple cycles of proliferation could lead to cell death. Also the inhibition of telomerase in the normal cells will results in numerous side effects and might lead to non-telomerase based mechanism of telomere maintenance.

So the treatment strategies that inhibit telomerase would not be effective in treating cancer.

Cancer stem cells are the small pool of the cancer cells shares the similar characteristics with the normal stem cells found among the tumor cells, which have the ability to give raise to particular cancer cell any time even after the killing of tumor cells. With this cancer stem cell hypothesis, during the life time of the tumor any of the cancer cell can involve in tumor growth or develop resistance. On the basis of this theory, these multipotent nature of this cells results in heterogeneity within a tumor. These cell population responsible for tumor growth imply that indiscriminate killing of cancer cells won’t be effective in treating cancer.

So the cancer stem cell hypothesis complicate the strategies in treating cancer.