New Study Finds New Target GDF 11 on Triple-Negative Breast Cancer
등록일 2019년 01월 07일 화요일
수정일 2017년 11월 21일 화요일

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Researchers from the University of Virginia conducted a study to find the vulnerability of triple-negative breast cancer.Triple-negative breast cancer is a breast cancer diagnosis in which the cancer cells are negative for estrogen receptors, progesterone receptors, and the human epidermal growth factor receptor 2 or HER2 gene.

"We're interested in the variability that's characteristic of triple-negative breast cancer.We believe this variability gives clues to how the cancer arises, and clues to treatment possibilities that would exploit the way the tumors are regulated or misregulated as the cells communicate with each other," said Kevin Janes, an associate professor of biomedical engineering at UVA.

In collaboration with UVA pathologist Kristen Atkins, the researchers discovered that triple-negative breast cancer cells have an inactive growth differentiation factor 11, a tumor suppressor.They noted that activating the disengaged GDF 11 could inhibit the abnormal growth of the cancer cells.The GDF 11 was premature and only accumulated inside the abnormal cells.

"We're still early in this investigation, but it may be a step in the right direction for getting a handle on ways to target this very difficult to treat breast cancer subtype," said Janes.

GDF 11 as an Anti-Aging Protein

In a study published in 2015, GDF 11 has been suggested as an anti-aging protein by the researchers from Harvard University.The researchers found that GDF 11 in mice dropped as the animals got older.They injected the mice with the protein and noted its potential to reverse age-related heart thickening.Amy Wagers, a stem cell biologist at Harvard, and her collaborators also reported the capability of GDR 11 to regenerate brain and muscle cells in rodents.

However, high levels of GDF 11 can inhibit cell regeneration of muscles in young mice, according to David Glass, a muscle disease researcher at the Novartis Institutes for Biomedical Research.But Wagers's group said that the assay used to detect GDF 11 was flawed, and the Novartis researchers simply found immunoglobulin in their test, another type of protein that may arise in the blood.

"They actually had very consistent findings to ours with respect to the blood levels of GDF11/8 with the antibody we all used.But their interpretation was confused by this case of mistaken identity," said Wagers.

The researchers led by Wagers conducted a new study wherein mice were injected daily with GDF 11.The purpose was to shrink the heart muscle in old and young mice.But the researchers found that the mice models lost weight and they are still looking for the reason how it happened.For now, Wagers suggested that GDF 11 may have a window for therapeutic purposes.

Triple-Negative Breast Cancer

Triple-negative breast cancer is aggressive and difficult to treat.It accounts for at least 10 percent of all breast cancer cases.It also accounts for at least 25 percent of deaths from breast cancers.This subtype of breast cancer does not respond to the usual hormone therapies, such as tamoxifen or aromatase inhibitors, or therapies that target the HER2 gene.

The current treatment available for triple-negative breast cancer is surgery, chemotherapy, and radiation therapy, which all carry potential side effects.Even with these treatment options, remission against the cancer subtype is very low.Here are some of the known behaviors related to triple-negative breast cancer.

1.It can be more aggressive than any other type of breast cancer – A study published in 2007 involving 1,600 women diagnosed with triple-breast cancer had been found to have a higher risk of reoccurrence outside the breast for the first three years.After that, the chance of reoccurrence became similar to the other breast cancer types.

2.It is often classified as high-grade cancer compared to any other type of breast cancer The grade measurement is used to determine the aggression and tendency to spread of cancer cells, and number 3 is the highest grade.Triple-negative breast cancer is a grade 3 cancer subtype.

3.It usually appears as basal-like – It means that the cancer cells appear similar with basal cells lined at the breast ducts.Cancers that are basal-like can happen without a family history or can be associated with genetics.

In addition to surgery, chemotherapy, and radiation therapy, patients diagnosed with triple-negative breast cancer may be treated with neoadjuvant therapy or poly ADP ribose polymerase or PARP inhibitors.

In neoadjuvant therapy, therapeutic agents are administered first before the main treatment.The goal of the therapy is to reduce the cancer's size or extent before any of the main treatments are involved.This can make any surgical procedures easier, increase the chances of treatment to succeed, and reduce the possibility of a more extensive treatment.As a result, the therapy can make untreatable tumors become treatable.

Using PARP inhibitors involve the intake of drugs designed to block the PARP enzyme.The PARP enzyme is used by cells to repair the damage of their DNA, and drugs that inhibit this can prevent cancer cells from repairing themselves after taking damage from chemotherapy.

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