The word “cancer” can strike fear in the heart of anyone. For most of medical history, the exact causes of unchecked tumor growth have been shrouded in mystery, rendering cancer a formidable enemy. Cancers usually were not detected until advanced stages, often too late for successful treatment or to prevent metastasis. Because tumor growth was so poorly understood, early cancer treatments themselves were toxic, broad-spectrum concoctions that often did irreversible collateral damage to the patient’s body.
Modern advances in genetic decoding, however, have begun to shed light on the molecular mutations that cause the most common cancers, allowing doctors to treat sooner, sometimes even before the onset of disease, and with greater accuracy. The process of identifying cancer-prone genetic mutations is called genotyping. Gene sequencing separates and “types” or identifies the known mutations that are associated with cancer. This can be done with biopsied tumor cells in order to create a targeted chemotherapy regimen, or with normal cells to assess a person’s risk of developing cancer in the future.
The first and most well-known discovery of the oncological mutations is the HER-2 (human epidermal growth factor 2), a protein that, when expressing a specific mutation, produces an excess of HER-factor that promotes rapid breast tumor growth. Identifying this gene has allowed researchers to develop customized chemotherapy drugs that block HER-2 specifically, effectively cutting the mortality rate from breast cancer in half.
Since that initial revelation, genotyping has continued to change the odds in the war against cancer. Several further genotypes have been discovered, including additional mutations for breast cancer, as well as new markers for lung cancer, pancreatic cancer, HPV (which can later lead to cervical and throat carcinomas), lymphoma, and many more. Although a targeted therapy or medical treatment is not yet associated with every known mutation, alerting to their genetic presence allows patients and their doctors to take action earlier in the disease process or before any disease has developed.
Genotyping has altered the outlook for cancer patients dramatically. Where once cancer was assumed to carry a death sentence, genotyping offers hope. This technology allows us to see further into the patient’s future, create more effective chemotherapy regimens, and increase the chances of survival. In addition, the targeted therapies developed by virtue of molecular testing often spare patients the side effects and long-term damage that previous, more brutal, broad-spectrum regimens caused.
In the future, cancer therapies will continue to be based on molecular studies. Genotyping is currently the most exciting field of research for oncology. With any luck our genetic code will someday reveal that holy grail of medical miracles for which we are all holding our collective breath…the cure for cancer.