Question

Describe the general relationship that may exist between mutations and cancer. What role does the cell cycle play? How is this related to the cell cycle and mitosis?

Answer 1

Abnormal division and growth of cells is called Cancer, the increased metabolic rate, increased number of cells , contact inhibtion are properties of the cancerous cells. Mostly Mutations and cancer are nearly related, because most of the cancers are caused due to mutation in the genes.

In our body few genes which are resposible for the specific functions those are very sensitive for the mutation due to varied reasons such genes are called oncogenes, the protooncogenes are activated to Oncogenes, this is caused due to the acquired or germline cancers. When the UV light falls on the cells which causes the thymidine dimers in the gene sequence which impairs the function of the DNA sequence, such cancer are called Sporadic cancers.

Germline cancer are very less common which are heritable from the generations. These are called inherited cancers.

Human Genes which mostly associated to cancer causatives are : 1. HER2, BRCA1, BRCA2,BRCA3 which causes breast cancer, ovarian cancers.

2) Cell cycle consists of G1, S, G2 and M phases in which cell decides to divide or halt, due to mutation of the oncognes or tumour suppressor genes the impaired function of the cell cycle control check point causes cancer. There are group of proteins called CdCks these are cyclin dependent kinases which activates by the phosphorylation, due to mutation or damage of the cell the proteins functionality looses and normal cell transofrm into cancerous cell.

Tumour suppressor gene P53 is 53kDa protein which present in the G1 phase supress from the cell division progression so it blocks at cell cycle check point, due to impaired function of the TSG also leads to cancerous cell to develop.During cell damage the trigerring to Apoptosis is failed to do so and cell will continously divide and increase its number enormousl which formerly called as Cancer.

Chemotherapy, Radiotherapy is ways to treat cancer so Cancer also Can Answer.