Do genes determine vulnerability to cancer? Not necessarily

The gene is an inheritance unit of our DNA that determines our characteristics, including physical, behavioral and clinical, and the term "hereditary" means transmitted genes from a parent to the child. In cancer genetics, these terms are often used interchangeably.

The majority of us have a perception of genetics in terms of hereditary lineage. However, there are few gene mutations that are not inherited but that have been acquired during the life of an individual due to a set of predisposing events or habits. of life.

This brings us to the question: "What can genetics do in cancer apart from susceptibility to hereditary predisposition and vulnerability to cancer?" The answer is the triangle D-P-T (Diagnosis-Prognosis-Therapeutic).

For example: A 63-year-old man develops lung cancer without any of his first / second degree relatives being diagnosed with cancer. These are sporadic cancers accounting for more than 85% of newly diagnosed cancers. Scientific research has made a significant contribution to our understanding of lung cancer, its emergence and the importance of screening for mutations that cause cancer, which helps physicians provide targeted treatment to kill or conquer cancer.

The presence of an EGFR gene mutation in lung cancer implies that a particular clbad of anticancer drugs is very effective in killing lung cancer cells and thus improving the quality of life and survival of the lungs. ;a patient. Beyond this, research has identified a subsequent secondary mutation of the EGFR gene in patients already taking a targeted drug. These mutations make the cancer cells resistant to the drug.

To meet this challenge, fourth generation drugs are being prepared that could specifically kill cancer cells that have developed resistance to first, second, and third generation drugs. This is a clbadic example of how genetic testing has helped in cancer treatment planning and management, as well as an example of cancer genetics beyond heredity.

* Cancer Genetics in Diagnosis

An accurate diagnosis of a type or subtype of cancer may be helpful in better managing the disease. There are many other cases where the mutation of genes confirms the diagnosis and thus directs the continuation of the operations. For example, in leukemia, there is a set of genes, if mutated, that distinguish the myeloproliferative neoplasm (MPN – a type of leukemia) from other benign causes of cytopenias (reduction of mature blood cells).

* Cancer genetics in prognosis

The prognosis in simple terms means the prediction of how the disease will evolve. This app is useful for understanding whether the disease requires aggressive treatment or not. For example: There is a standard recommendation for mutation testing of the IGHV gene in chronic lymphocytic leukemia. If this gene is mutated, clinical studies have shown that these patients do not have an aggressive disease phenotype and therefore may not require aggressive treatment. However, in patients who did not mutate for the IGHV gene, clinical studies have shown that the disease progresses aggressively and that the treatment regimen can be modified to improve the quality of life and survival of these patients.

* Cancer genetics in therapeutics

The term targeted therapy would not be the same in cancer, if not for genetics. There are certain genes that are useful in the treatment decision, called tumor oncogenes / suppressors, in which a sporadic mutation modifies the function of gene-inducing cell processes leading to uncontrolled cell division causing cancer. This intrinsic property of the cancer cell is advantageous for drug manufacturers to develop molecules that block the protein and inhibit the progression of cancer or kill cancer cells.

In India, the application of genetic cancer tests to therapeutic decisions has increased significantly, particularly in lung, bad, gastrointestinal and colorectal cancers.