Scientists from the United States have identified two subtypes of metastatic prostate cancer that respond differently to treatment. Information that could one day guide doctors to treat patients with the most appropriate therapies for their disease improving their health.
According to published In the journal JAMA Oncology, building on previous studies that discovered clinically relevant subtypes of non-metastatic prostate cancer, researchers identified genetic signatures. Which can divide metastatic prostate tumors into two types known as luminal and basal.
The luminal tumors respond better to blocking treatments of testosterone, whereas the basal ones did not benefit as much from this hormonal treatment.
The basal tumors also included the especially aggressive form of the disease metastatic cancer known as neuroendocrine small cell prostate cancer.
More clinical trials will be needed before a new selection of treatment based on the
The reason these subtypes are important is that they respond to hormone therapy very differently, says Shuang Zhao, professor of oncology at the College of Medicine and Public Health. from the University of Wisconsin, United States in.
The experts emphasize the importance of the investigation of the different subtypes
A few ago 20 years, scientists discovered the luminal and basal subtypes of breast cancer and found that each responds better to different therapies. This has provided physicians with greater precision in treating their breast cancer patients in.
Since breast and prostate cancers share many similarities, in 2016 Zhao’s team analyzed whether these similarities extend to the different subtypes of prostate cancer .
They published the first report that identified the luminal and basal subtypes in localized prostate cancer. When the disease remains confined to the prostate.
The new study expanded the analysis to metastatic cancer , when the disease spreads from the prostate.
metastatic prostate cancer is much more lethal than its local version. It is also more difficult to study, because small tumors can be in many different parts of the body and are more difficult to biopsy.
So, to identify enough samples for analysis, the Zhao’s team resorted to multiple large studies in the United States on patients with metastatic prostate cancer.
This is how the study proceeded. US study on metastatic prostate cancer
The team had a total of 634 samples of patients. They used computational methods to compare gene expression patterns in tumor biopsies in.
A group of 50 genes determine the basal or luminal nature of breast and prostate cancer. And, based on the activity of each of these genes, scientists can separate the two subtypes.
As in the case of prostate cancer located, Zhao’s team identified the luminal and basal types also in the case of metastatic cancer. They then asked how the subtypes affected patient survival and response to treatment .
study patients did not know the subtypes at that time, they had to decide which treatment they thought might work better without this information.
Variation in treatment produced a natural experiment that the researchers were able to analyze.
And we discovered that, as in the localized prostate cancer , hormonal therapies seemed to work better in luminal tumors than in basal tumors, Zhao notes.
Although there were two clear subtypes, the researchers They also saw that the tumors were located in a spectrum according to their degree of luminosity or basality. At one extreme were small cell neuroendocrine prostate cancers resistant to hormonal treatment , which seemed the most basal.
At the other extreme were less aggressive luminal subtypes, which are more sensitive to hormone therapy a lot.