Biomarkers are molecular or cellular changes in human tissues that can be used a
ID: 62085 • Letter: B
Question
Biomarkers are molecular or cellular changes in human tissues that can be used as a specific marker for a disease such as cancer. Identifying biomarkers for earlier detection of cancer or for determining the likelihood of cancer progression is an area of extremely active research. While researchers had originally hoped to identify a single biomarker common to all cancers, they have since revised their identification strategies because single biomarkers do not seem to be capable of the specificity and sensitivity levels necessary for routine clinical use.
What are some of the primary reasons why a single cancer biomarker is no longer believed to be realistic? Specifically, what are some examples of variables that can reduce the specificity of cancer biomarkers?
What is meant by the “peptidome hypothesis,” and how can it be used to identify novel biomarkers? Why is the blood peptidome particularly well-suited to identification of novel biomarkers of cancer, specifically?
Explanation / Answer
It is not a fact that the dysregulation of limited amounts of oncogenes or tumor-suppressor genes involved in cancer. Since, cancer leads to the aberration of many other genes that involve directly or indirectly in the tissue -specific carcinogenesis and tumor progression. Hence, considering of a single biomarker is no longer believable and realistic in the diagnosis of cancer. Age, sex, genetic background (race), nutritional factors, default immune settings and co-infections (antigenic variability) affect the specificity of cancer biomarkers.
The specific low-molecular weight peptide or protein associated with cancer can be identified by parallel analysis of thousands of genes and proteins through mass spectrometry and protein and DNA arrays that combined with the knowledge of human genome by comparing with the normal cells. The blood circulatory system consist of a low-molecular-weight proteome is called the 'peptidome' that could be rich in cancer-specific diagnostic information since, it is the representative of the several Intra and extracellular activities that take place in the cancer tissue microenvironment. This blood peptidome typically exists in a bound state with high-abundance proteins like albumin. Its measuring is more sensitive and specific than conventional biomarkers for cancer diagnosis.
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.