Biomarkers can be comprised of genetic material or protein (s), for example, a mutation in a specific gene or genes, a level of a hormone, or the presence of a type of immune cell. Biomarker tests are a way to detect genes, proteins and other substances (called biomarkers or tumor markers) that can provide information about cancer. Each person's cancer has a unique pattern of biomarkers. Some biomarkers affect the functioning of certain cancer treatments.
Biomarker tests can help you and your doctor choose a cancer treatment for you. Biomarkers have many potential applications in oncology, such as risk assessment, screening, differential diagnosis, determining prognosis, predicting response to treatment, and monitoring disease progression. Because of the fundamental role that biomarkers play in all stages of the disease, it is important that they undergo a rigorous evaluation, including analytical validation, clinical validation and evaluation of their clinical utility, before they are incorporated into regular clinical care. In this review, we address key steps in biomarker development, including ways to avoid the introduction of biases and the guidelines to follow when reporting results of studies with biomarkers.
Cancer biomarkers are a wide variety of endogenous molecules, including DNA, transcription factors, cell surface receptors, metabolites, and secreted proteins produced by tumor tissue or other tissues in response to the presence of cancer or other associated conditions, such as inflammation. Cancer biomarkers can also be processes such as apoptosis, angiogenesis or proliferation. A tumor marker is any element present or produced by cancer cells or other cells in the body in response to cancer or certain benign (non-cancerous) conditions that provides information about a cancer, such as its degree of aggressiveness, the type of treatment it may respond to, or whether it responds to treatment. A biomarker is a biological molecule that can be detected in physiological fluids, tissues and blood and is used as a marker of a good or unhealthy process or of a disease such as cancer, according to the National Cancer Institute. Each of the characteristics of cancer is implicated in numerous essential biomarkers that play a vital role in tumor progression.
As secondary genetic products, glycan information reflects the impact of internal and external factors, such as diseases, lifestyle and social factors, on a person's health and illness, providing a rational explanation for why the cancer biomarkers that are currently used are highly dependent on the structure of glycans. Biomarkers can be used to evaluate patients in multiple clinical settings, including estimating disease risk, detecting hidden primary cancers, distinguishing benign findings from malignant findings or one type of malignant neoplasm from another, determining prognosis and prediction for patients who have been diagnosed with cancer, and monitoring disease status, either to detect recurrence or to determine response or progression to treatment. Because of the risk of false-positive or negative results, relying solely on one level of biomarker is not an accurate and reliable strategy for diagnosing tumors. The evaluation of clinical utility includes an evaluation of the efficacy of a biomarker, as well as of the benefit-harm ratio. Consequently, the biomarker is described as “a defining characteristic that is measured as an indicator of normal biological processes, pathogenic processes, or responses to exposure or intervention, including therapeutic interventions.
Cancer biomarkers are discovered and used with a specific purpose in mind, such as (a) early detection of cancer, (b) diagnosis, (c) prognosis, (d) response to cancer treatments, or (e) cancer recurrence (fig. We address the topic of systemic inflammation in cancer patients as a factor that is often overlooked when interpreting the biomarker profiles of cancer patients, which is not specific and often cannot be distinguished from the inflammatory symptoms that accompany many other diseases (fig. Therefore, guidelines have been developed for reporting the results of biomarker studies to ensure that all necessary information is included. An illustrative example of the use of biomarkers to elucidate the causal pathways of cancer are studies that examine the association between obesity and associated metabolic complications and breast cancer. Many modifications to this basic method are being continuously developed to increase sensitivity in detecting biomarkers from trace sources.
Over the past few decades, continuous progress has been made in the exploration and discovery of novel, sensitive, specific and precise tumor biomarkers, which has significantly promoted personalized medicine and improved outcomes for cancer patients, especially advances in molecular biology technologies developed for detection of tumor biomarkers. Significantly, multiple biomarkers lead to monitoring and predicting the therapeutic response of personalized and precision medicine in clinical practice,1386, which highlights the fundamental position of tumor biomarkers in cancer therapy.
