Scientists from the Federal University of Uberlândia (UFU), in Minas Gerais, work on the development of a liquid biopsy test able to detect prostate cancer through the blood. Research advances in identifying which membrane protein of the circulating tumor cell present in the blood of patients binds to the molecule used in the tests.
On the diagnostic platform developed at the university, the patient’s blood is collected as in a common test. In the laboratory, the sample passes through two machines: a centrifuge, which separates its parts, and a piece of equipment called a flow cytometer, which counts and classifies the cells.
In this process, it is possible to observe the presence of normal cells, which are detached from the organs in the natural process of renewal, and the presence (or not) of tumor cells that can also circulate through the bloodstream.
The researchers are now seeking to identify whether there are tumor cells among the normal ones circulating in the blood. The work has the participation of specialists Vivian Alonso Goulart, professor at the Institute of Biotechnology (IBTEC); Esther Campos Fernández, PhD student at the Graduate Program in Genetics and Biochemistry (PPGGB); and Nathália Oliveira Alqualo, undergraduate student in Biomedicine and scientific initiation scholarship holder at the National Council for Scientific and Technological Development (CNPq).
Based on previous experiments carried out at the university’s Nanobiotechnology Laboratory and on database analyses, the scientists found which protein on the tumor cell membrane binds to the marker molecule they use in the study, the A4 aptamer. These are proteins located in the membrane that lines each prostate cancer cell.
Afterwards, the researchers analyzed a strain used for research on prostate tumor cells in equipment called a mass spectrometer, which identifies molecules by measuring their mass (or the amount of matter that composes them) and their characteristics. On this spectrometer, they applied a technique to identify proteins in a biological sample.
Three probable target proteins for the A4 aptamer that may be associated with prostate cancer were identified: ADAM30, NXPE2 and MUC6. In the future, they may be validated as biomarkers for diagnostic platforms, enabling the early diagnosis of prostate cancer.
The researchers point out, however, that the diagnostic platform proposed in this research will be complementary to the tests for Prostate Specific Antigen (PSA) and digital rectal examination, which are currently used to identify prostate cancer.
Prostate cancer is considered a silent disease, which does not usually show signs or symptoms in the early stages. Some patients may experience symptoms such as difficulty urinating, decreased urine output, a greater need to go to the bathroom, in addition to the presence of blood in the urine.
The disease has variable evolution profiles, and may present a slow or fast growth, from one patient to another.
Touch examination is one of the screening methods for early detection of cancer. The test allows the doctor to check the structure of the prostate, as well as possible signs of enlargement or other changes. With aging, the prostate can increase in size naturally, without any kind of disease.
The Brazilian Society of Urology (SBU) recommends that men, from the age of 50, and even without showing symptoms, seek medical attention, for individualized evaluation with the aim of diagnosing cancer early.
The touch exam can be performed annually from the age of 50 for the general population, and should be started at the age of 45 for men who are part of the risk group, especially those who have a family history of the disease.
To clarify the diagnosis, specialists also use another indicator called prostate-specific antigen (PSA). Although the protein is naturally produced by the gland, the increase in the level of PSA present in the circulation may indicate the need to investigate the presence of a tumor.
The PSA test is carried out from the collection of blood, which allows measuring the levels of the molecule in the body. The results are then compared by the doctor with other factors such as the size of the prostate, the patient’s age and the presence of nodules or inflammation in the prostate.
(With information from the UFU Communication)
Source: CNN Brasil