[메디컬리포트=KC Jones 기자] Tests related to prostate cancer keep being improved, and a new three-in-one test may change the landscape entirely.
Scientists say there modern medicine may be inching closer to precision-personalized treatment when it comes to prostate cancer thanks to a new blood test.What makes this new test somewhat revolutionary is that it can potentially overhaul the contemporary approach to disease by targeting individual gene mutations, according to researchers.
Researchers identified men with defective BRCA genes by examining blood samples for cancer DNA, and these were all men likely to benefit from what are called Parp inhibitors, a certain class of drugs.The team also relied on the test for watching DNA in the blood respond to the start of treatment; this allowed them to immediately switch any patient who wasn’t responding to the treatment off of it and onto alternative therapy.
Lastly, the team also used this same test as a way of detecting the evolution of cancer in such detail as to notice early indications of drug resistance, which creates a distinct advantage in dealing with cancer.They now consider the new blood test to be a three-in-one test because of its potential to provide all these things.Professor Johann de Bono was the team lead from the Institute of Cancer Research in London, and he said, “We were able to develop a powerful, three-in-one test that could in future be used to help doctors select treatment, check whether it is working and monitor the cancer in the longer term.
“We think it could be used to make clinical decisions about whether a Parp inhibitor is working within as little as four to eight weeks of starting therapy,” de Bono continued. “Not only could the test have a major impact on treatment of prostate cancer, but it could also be adapted to open up the possibility of precision medicine to patients with other types of cancer as well.”
The purpose of Parp inhibitors like olaparib is to block an enzyme that cancer cells with defects in genes BRCA 1 and 2 use to repair their own DNA.The cells die when Parp is blocked, but cancer cells with properly functioning BRCA genes usually are not affected by Parp inhibitors.This is because they are not dependent on Parp, which they shouldn’t be if they’re functioning properly.Some patients’ bodies respond quite measurably to the drugs for consecutive years whereas others don’t respond even at the early stages.Others still actually develop cancer that is particularly resistant even.
There were 49 patients who contributed themselves to the requisite testing to develop this test as they were all enrolled in a Phase II clinical trial called TOPARP-A that researches the efficacy of olaparib.The development of this test actually culminates or furthers a series of developments with regard to various types of tests related to the treatment of prostate cancer.For many of the last several years, there have been advancements made apropos of some sort of prostate cancer-related testing as a result of studies conducted by researchers with patients enrolled in some kind of program.Studies in 2008, 2009, 2010 and 2012 in particular exemplify how this kind of progress is constantly being made.One study simply takes the implications of a previously published study and formulates hypotheses to test on that basis.
All cancer is considered to be among the utmost public health priorities, and the urgency of this becomes compartmentalized when looking at the more prevalent subtypes like prostate cancer.Within risk assessment research on prostate cancer testing, it is understood that hypermethylated DNA can be found in the blood of patients with prostate cancer, serving as a biomarker.The significance of this observation is that a priority concern in relation to prostate cancer is non-invasive testing due to the discomfort of prostate examinations.
The study conducted in 2008 addressed the question of non-invasive testing for the aggressiveness of tumors in localized prostate cancer.It was particularly concerned with ensuring the non-invasive means since testing is already fairly accurate, and the observation put to the test was the potential for diffusion-weighted MRI testing to serve as a viable biomarker.The study classified forty-four consecutive patients into three categories based on their varying levels of risk for prostate cancer, and only intermediate- and high-risk patients received any kind of therapy.The study was published in the medical journal, Clinical Radiology, by Nandita deSouza and his team at the Institute of Cancer Research, which included Geoffrey Payne who later made further progress along the same lines.
Building on the same concepts the following year, Payne described prostate cancer biomarkers as a public health priority, emphasizing specificity regarding prostate-specific antigen.The novelty of the 2009 study was that they were testing the potential for hypermethylated DNA detection in the body fluids (mainly blood) of prostate cancer patients as an efficient biomarker.They concede that the clinical performance of hypermethylated DNA varies from one study to another, which they base not just on their own research but also related research that indirectly prompted the study.
The 2010 summary, published in Molecular Cancer, accomplished more than gathering data because it also evaluated the data in its own systematic study.In it, there is an expression of urgency for the discovery of novel biomarkers to improve the clinical management of cancer and diagnosis, declaring the ideal biomarker to be one that is seamlessly observable by non-invasive means.
The 2012 study selected subjects with gastric cancer from two cohort studies to identify differential microRNAs in their serum pools, and it attempted to make the same identification via TaqMan low density array for another group of subjects, effectively making them a control group.It also involved a retrospective study of a long-term follow-up group of 58 other gastric cancer patients who each had a minimum of one pre-diagnosis serum sample.
The results of microRNA profiling in the 2012 study showed 16 microRNAs as considerably upregulated in gastric cancer subjects compared to controls.The significant implications of this flagged three microRNAs as potential biomarkers, and in tandem with the data extracted from the 2010 summary, this supports the notion that serum microRNAs may be the optimal target for researching non-invasive methods of testing for prostate and other cancers.
The first two studies mentioned (deSouza in 2008 followed by Payne in 2009) showed the scope of the demand for non-invasive testing methods as they built upon the hypotheses of previous research and further explored novel observations.These studies logically led to the increase in the amount of attention being paid to microRNAs for discerning non-invasive means of detection for prostate cancer.
Implications that can be determined from these studies for the future include the likelihood that more and more attention will be paid to microRNAs.Non-invasive testing may, indeed, be a common reality within the next decade or two because what remains is the removal of variables in clinical results.