Two new studies claim that a unique but ubiquitous hormone known as prolactin contributes to producing milk during pregnancy, which can be the primary driver of breast cancer.

The findings were led by Dr. Charles Clevenger from Virginia Commonwealth University, who has been examining to find the untangle prolactin’s important role in breast cancer. He started the research ever since he found the first evidence describing the growth factor that could be the reason for the disease in the middle of the 1990s.

 May Contribute to Breast Cancer 

The new two studies show that the presence of some prolactin receptors can convert abnormal breast cells into cancerous cells.

The second paper demonstrates how blocking cell signaling pathways can also prevent cancer cells from multiplying. It can be performed with a drug that is presently being tested in early-stage clinical tests to treat multiple myeloma and non-small lung cancer.

This study could help other researchers discover new therapies for breast cancer made to target particular versions of the prolactin receptor. If the therapies are developed, that could be helpful to treat various subtypes of the disease.

Cleavenger stated in 1998 that most mammary( breast)tissues create their own prolactin and also contribute to breast cancers. He published the findings by describing that over 95 per cent of all breast cancers involved prolactin and its receptor.

But the significant role of prolactin and its receptor in breast cancer is not completely proved and researchers failed to notice for decades that there are various forms of the prolactin receptor. Each one functions differently during pregnancy and disease that scientists are still trying to find out.

Understanding prolactin’s contribution to breast cancer was also invalidated by a slew of clinical trials in the 1980s. The study failed to prove any benefits of drugs targeting prolactin hormone is responsible for breast cancer. Later, scientists decided to focus on its contribution in stimulating breast cancer tissue development and milk production.

The recent study challenges the dogma that prolactin only works in milk production and shows the unique discovery that hormone plays a role in breast cancer. Clevenger explained these two studies.

By learning prolactin receptors and how it is linked with breast cancer, may lead to producing new therapeutic and prognostic agents that can be created to treat the disease effectively.

Firstly, the team found a modified version of the prolactin receptor(dubbed hPPLrl) and demonstrated that it has the ability to turning benign breast cells with zero potential to transfer the cancer cells to the body. It can happen only when it is co-expressed and communicating with other kinds of prolactin receptors.

Eliminating the hPPLr receptor from lab-grown breast cancer cells also decreased the cells’ malignant abilities.

Researchers also referred to the data from The Cancer Genome Atlas to validate these cell-based tests.

They discovered that higher levels of the hPRLr receptor in tumor tissues(which is relative to its fully-grown counterpart) were linked with more aggressive breast cancers, called triple-negative breast cancer that has very few treatment options experience the worst outcomes for people who are diagnosed.

There is some great news. In the 2nd study, the scientists proved that using multiple breast cancer models that include patient donated cells and genetically engineered rats and how breast cancer progress could be blocked using the HDAC6 inhibitor. This drug blocks a protein connected with prolactin. 

Clevenger further stated that, as per Global analysis of gene expression, prolactin is linked with breast cancer growth and can be stopped by treatment with an HDAC6 inhibitor.

These ongoing studies showed some new insights and added some additional evidence for prolactin’s role in breast cancer progression. Still, more research is required to describe cancer and its complications.