Over the last decade, several studies investigated on the opportunity of fighting cancer by encouraging the immune system to fight cancer cells. White blood cells of the immune system such as the T-cells may, in fact, target specific portions of the tumor cells called “antigens.” Finding these “weak spots” may pave the road to future personalized cancer cures such as specific vaccines which may fight as well as prevent cancer itself. The principal limitation of cancer immunotherapy, however, is the inability to recognize cancer cells, which often avoid the attack of these “natural sentinels” by mimicking normal cells’ behavior.
Conventional cancer treatment is usually detrimental to a patient’s health, as cancer chemotherapy acts by killing cells without discriminating “good” (healthy) cells from “bad” (cancerous) ones. Also, many of the chemotherapy drugs’ side effects and toxicity are very heavy and hard to endure for a patient whose overall condition is already critical. Most of modern medicine’s efforts to fight cancer did, in fact, concentrate on preventing it rather than fighting it with strategies such as precocious screening, lifestyle changes promotion and reduction of risk factors. Recent cancer studies proved that this strategy was quite effective in most Western countries, although the battle against cancer is still far from being won. Every year almost 600,000 people will, in fact, die of cancer in the United States, with breast and lung cancer being the most common forms of this disease.
The new study, which has been published in the journal Science, found a way to help immune cells identifying their correct targets by recognizing specific mutations on tumor cells. One of the study co-authors, Dr. Sergio Quezada, compared the cancer cell’s mutations to various types of crimes that T-cells should recognize and fight just like an army of policemen struggling against a vast amount of criminals. Helping those zealous officers find and identify these “gang members” will improve their efficiency and allow them to overcome the terrifying menace.
The research team used data from The Cancer Genome Atlas (TCGA) to investigate more than 200 patients affected by lung cancer, and pinpoint all its genetic variations. Scientists identified which antigens were common across cancer cells, and then isolated white blood cells taken from patients’ blood samples. Some of those T-cells were able to recognize the antigens and kill cancer cells, but as the tumor grows, the number of new mutations becomes so large that immune cells are not able to recognize them anymore. By harvesting those cells that can efficiently fight the tumor, however, the research team suggested two different strategic options to defeat it. The first one is to artificially grow and multiply them in a laboratory setting and then re-inject them into the patient, like a massive “reinforcement” army. The other one is to develop a personalized vaccine that helps T-cells within the body to spot cancer cells by “training” them to recognize the various mutations.
Following Dr. Quezada’s metaphor, these solutions assist the policemen fight the correct and most dangerous crimes instead of chasing minor or non-relevant ones, and defeat the “kingpins” of the organized crime underground. This new research may pave the road to new personalized treatment for cancer that may prevent patients from being administered the most toxic cancer chemotherapy drugs to save their lives.
