Understanding the biochemistry of cancer

Understanding the Biochemistry of Cancer

Cancer is a complex and challenging disease that affects millions of people every year. It is caused by uncontrolled cell growth and division, which can lead to the formation of tumors and the spread of cancerous cells to other parts of the body. Despite decades of research, cancer remains a major health concern, and there is still much to be learned about its underlying biology. In this article, we will explore the biochemistry of cancer, including the genetic and molecular mechanisms that drive its development and progression.

Cancer and Genetics

Cancer is fundamentally a genetic disease, caused by mutations in the DNA sequence of genes that regulate cell growth and division. These mutations can occur spontaneously or be triggered by external factors such as radiation, chemicals, or viruses. When a cell divides, it must replicate its DNA to ensure that each new cell has a complete set of genetic instructions. However, if errors occur during DNA replication or repair, the resulting mutations can disrupt the normal function of genes, leading to unregulated cell growth and cancer.

There are two broad categories of genes that are involved in cancer: oncogenes and tumor suppressor genes. Oncogenes are genes that promote cell growth and division, and mutations that activate these genes can cause unlimited cell proliferation and the formation of tumors. Tumor suppressor genes, on the other hand, are genes that inhibit cell growth and division, and mutations that inactivate these genes can remove the brakes on cell proliferation, also leading to cancer.

In addition to mutations in oncogenes and tumor suppressor genes, there are also other genetic changes that can contribute to cancer. For example, abnormalities in DNA repair genes can lead to an accumulation of mutations and increase the risk of cancer. Similarly, abnormalities in genes that control cell death or apoptosis can prevent damaged or abnormal cells from being eliminated, allowing them to continue to grow and potentially become cancerous.

Molecular Mechanisms of Cancer

While genetics plays a critical role in cancer, it is not the only factor. Cancer is a complex disease that involves multiple molecular pathways and cellular processes. One of the key features of cancer is the ability of tumor cells to evade the normal regulatory mechanisms that control cell growth and division.

One of the ways that tumor cells can escape these controls is by activating signaling pathways that promote cell growth, such as the PI3K/Akt/mTOR pathway or the Ras/Erk pathway. These pathways can be activated by mutations in oncogenes or by changes in the activity of signaling proteins that regulate these pathways. Once activated, these pathways can stimulate cell proliferation and survival, even in the absence of external growth signals.

Another important mechanism in cancer is the dysregulation of the cell cycle. The normal cell cycle consists of several stages, including a growth phase (G1), DNA replication (S), a second growth phase (G2), and cell division (M). During each of these stages, the cell is subject to regulatory checkpoints that ensure that it is ready to proceed to the next stage. However, in cancer cells, these checkpoints can be overridden or disrupted, allowing cells to progress through the cell cycle even in the presence of DNA damage or other abnormalities.

Cancer cells can also resist apoptosis, or programmed cell death, which is a natural process that eliminates damaged or abnormal cells. Normally, cells undergo apoptosis when there is damage to their DNA or other cellular components, or when they are no longer needed. However, in cancer cells, this process can be disrupted, allowing damaged or abnormal cells to survive and potentially become cancerous.

Finally, cancer cells can also develop the ability to invade and metastasize, which is the process by which cancer cells spread from their primary site to other parts of the body. This process involves a complex interplay of cellular adhesion molecules, extracellular matrix proteins, and signaling pathways that regulate cell migration and invasion. By acquiring the ability to invade and metastasize, cancer cells can spread throughout the body and establish secondary tumors in distant organs.


Understanding the biochemistry of cancer is essential for the development of new treatments and therapies. Cancer is a complex disease that involves multiple genetic and molecular mechanisms, and there is still much to be learned about its underlying biology. However, through continued research and innovation, we can hope to develop more effective therapies that target the specific molecular pathways and cellular processes that drive cancer growth and progression.