Scientists of the Medico-genetic scientific center (mgnts) develop a new approach that will help to determine how necessary preoperational chemotherapy in patients with breast cancer. Now half of patients receive this therapy in vain, reported the press service of the center.
The fact is that at present, oncologists prescribe neoadjuvant (preoperative) chemotherapy is almost blind – it is impossible to say it works or not. Such treatment may be useful, but may not produce any positive result. In this case, would be loss of precious time. Now the purpose of preoperative therapy is risky.
Head of the laboratory of epigenetics mgnts CV:
“The effectiveness of different schemes of neoadjuvant therapy for different subtypes of breast cancer ranges from 30 to 60%. If successful, the tumor completely disappears from the breast tissue, it is called a complete pathological regression. However, the physician needs to accurately determine in which cases to assign to neoadjuvant therapy. In fact about half of the patients receive it in vain.”
Currently, a few doctors tools that could predict how effective preoperative chemotherapy, the researchers say.
“So our goal is to develop a system of a priori forecast the effectiveness of therapy. That is, a system that would allow to clearly identify patients in need of neoadjuvant therapy will bring the greatest benefit”, – said Vladimir Strelnikov.
Today molecular profiling in Oncology is based mainly on the determination of gene expression (the process of converting genetic information in the desired product, e.g., protein is the main structural material of the body).
But this figure is unreliable, scientists say. Because different biopsy specimens may show different expression depending on how many tumor cells caught in the tissue taken for analysis.
The effectiveness of neoadjuvant chemotherapy genetics propose to determine through the assessment of methylation level. According to scientists, it is a measure of how methylated genes in tumor cells gives the most informative.
Methylation is the unification of chemical compounds, methyl groups, to DNA. The DNA strand they do not destroy, but they influence the activity of genes is the production of a protein, and often overwhelm her.
Geneticists held shirokorulonnye analysis of methylation in the collection of samples of breast tumors. From the entire set of genes, the scientists chose 12, the degree of methylation of which it is possible to predict how effective neoadjuvant therapy.
It turned out that preoperative chemotherapy is most effective for samples in which the level of methylation was high in the case of moderately methylated samples chemotherapy had virtually no success.
The study, which has lasted five years so far to complete. In the future we plan to conduct clinical trials. The results of the study will be presented in three years.