Development of drug targets
In addition to being utilised in cancer treatment, biomarkers are frequently used in the search for new cancer treatments. For instance, in the 1960s, scientists found that the Philadelphia chromosome, a specific genetic aberration on chromosomes 9 and 22, was present in the majority of patients with chronic myelogenous leukaemia. These two chromosomes come together to form the BCR-ABL gene, which causes cancer.
This gene serves as the main starting point for all of the physiological signs of leukaemia in such people. The BCR-ABL was merely employed for many years as a biomarker to stratify a certain subtype of leukaemia. Imatinib, a potent medication that efficiently blocked this protein and markedly reduced the creation of cells carrying the Philadelphia chromosome, was finally created by pharmacological researchers.
The use of surrogate endpoints is another promising avenue for biomarker use. In this application, biomarkers stand in for a drug’s impact on the development and prognosis of cancer. The ideal scenario would be to avoid the need for extensive clinical trials and tumour biopsies in patients by using verified biomarkers. According to the current standard of care, a drug’s success is assessed by looking at whether it has slowed the progression of cancer in humans and, eventually, whether it extends survival. However, if unsuccessful medications could be removed from the development pipeline before being put through clinical trials, successful biomarker surrogates might save a significant amount of time, energy, and money.
The following are some desired characteristics of surrogate endpoint biomarkers:
- The cancer-causing mechanism should include biomarkers.
- Changes in the disease should be reflected in changes in the biomarker.
- Biomarker concentrations should be high enough to allow for accurate measurement.
- Normal, malignant, and precancerous tissue should be easily distinguishable based on biomarker levels or existence.
- The level of the biomarker should vary after effective cancer treatment.
- The biomarker’s level shouldn’t fluctuate randomly or in reaction to elements unrelated to the successful treatment of cancer.
- Circulating tumour cells (CTCs) and circulating miRNAs are two areas in particular that are being looked at as surrogate markers. Both of these markers are thought to serve as a proxy for tumour growth and metastasis since they are connected to the number of tumour cells in the blood. The difficulties of enriching, detecting, and measuring CTC and miRNA levels in the blood, however, is a major hurdle to their implementation. For their integration into clinical treatment, new technologies and research are probably required.
Cancer biomarkers without specificity
Not all cancer biomarkers must be able to identify a particular form of cancer. The circulatory system has some indicators that can be utilised to identify aberrant cell proliferation in the body. One of the key benefits of routine health testing is the ability to detect all these different sorts of biomarkers through diagnostic blood tests. Regular testing allows for the early detection of numerous health problems, including cancer, which reduces mortality rates.
Numerous malignancies have been demonstrated to be non-specifically predicted by the neutrophil-to-lymphocyte ratio. This ratio focuses on the activity of two immune system elements involved in an inflammatory response, which has been demonstrated to be more active when malignant tumours are present. Basic fibroblast growth factor (bFGF), another protein, is also involved in cell proliferation.
Unfortunately, it has been demonstrated that it is extremely active in tumours, which has led to the assumption that it might promote the reproduction of cancerous cells. Anti-bFGF antibodies have been demonstrated to be effective in treating cancers with a variety of sources. In addition, insulin-like growth factor (IGF-R) contributes to cell development and proliferation. It may have a role in preventing apoptosis or the planned death of cells brought on by a malfunction. As a result, when cancers including breast, prostate, lung, and colorectum are present, IGF-R levels may surge.