A predictive biomarker is used to identify individuals who are more likely to respond to exposure to a particular medi[1]cal product or environmental agent. The response could be a symptomatic benefit, improved survival, or an adverse effect. Biomarkers assist in early diagnosis, ailment prevention, drug goal identification, drug reaction etc. Biomarkers are biological molecules found in tissues, blood, and other bodily fluids. They are signs that represent normal or abnormal processes, condi[1]tions, or diseases. Prognostic biomarkers are associated with clinical outcome and are used to identify patients with a more aggressive disease course. Predictive biomarkers are measures of the likelihood of responding or not responding to a particular therapy, allowing the identification of patients most likely to benefit from a particular therapy protect other patients from treatment toxicity. Prognostic markers help classify patients into groups, leading to accurate drug discovery. Commonly used prognostic markers in cancer include stage, size, grade, nodule, and metastasis. In addition to these general markers, there are prognostic markers specific to different types of cancer. For example, estrogen levels, progesterone, and HER2 are unique markers for breast cancer patients. There is ejvidence that genes that function as tumor suppressors or carcinogens may function as prognostic markers through changes in gene expression or mutations.

Traditional prognostic markers in oncology include tumor size, staging, lymph node proliferative status and me[1]tastasis. Large tumors, late staging, presence of cancer cells in multiple distant lymph nodes, and observation of metastases are often associated with a poor prognosis. In recent years, advances in molecular engineering, genomics, cancer biology and sequencing technology have created opportunities to discover and validate new biomarkers of prognosis, especially molecular prognostic markers. Expression of estrogen and progesterone receptors can deter[1]mine the blessings of hormone remedy, even as the gain of treating breast most cancers sufferers with Herceptin is decided via way of means of the expression of HER2. While DNA sequences suggest what a cell might be doing, expression pro[1]files tell us what it’s actually doing at a particular point in time. Whether certain mRNA molecules are present and at what level they are expressed suggests whether a particular gene is “on” and to what extent it is expressed. Therefore, mRNA profiling can provide more detailed and timely downstream transcriptional information about cancer. Technologies for mRNA pro[1]filing include RT-qPCR for sensitive analysis of a small number of mRNA targets, microarrays for multiplex profiling down to the transcriptome level, and next-generation RNA sequencing.

Regards
Robert
Managing Editor
Journal of Biomarkers in Drug Development