With a molecular form it acts as a biological marker or an indicator of any biological functions, responses to certain drugs of certain intervention of the therapeutic drugs and indicates some pathological paths. And in cancer, it indicates presence of cancer inside the body as it a molecule which is being secreted by the tumour or cancerous cell as a response, which determines the location of the cancerous cell in the body. Certain kinds of the biomarkers which were being used in the diagnosis of cancer as it can be assay by the collection of the fluids like blood, used as for prediction and well as for treating cancer. So many pharmaceutical companies were producing different sort of biomarkers. So it plays a vital role in the treatment in cancer.