Some Breast Cancers Fail to Respond to Treatments, Why?

Breast Cancer

Most breast cancers are estrogen receptor-positive, meaning that signals received from estrogen, a hormone, promote the growth of the tumors. To stop these cancers from spreading, estrogen inhibitors are usually prescribed. But what happens when tumors develop treatment resistance?

Studies suggest that "approximately 70 percent" of all the breast cancers are estrogen receptor-positive (ER-positive).

These types of cancer are typically treated with drugs — such as tamoxifen and fulvestrant — that either lower the levels of the hormone or inhibit the estrogen receptors to prevent the tumors from spreading. This is known as endocrine therapy.

However, around a third of the people treated with these drugs develop resistance to them, which negatively impacts their chances of survival. The mechanisms that underlie the tumors' resistance to therapy is not well understood and currently poses a major challenge.

Read More »

Melanoma May Be Stoppable With Drug That Halts Cancer Cell Proliferation

A drug already being tested in people as a treatment for cancer appears to show great promise in halting melanoma skin cancer. The drug - called pevonedistat - works in a way differently than intended and could also be effective against other cancers.

So says a new study from the University of Virginia School of Medicine in Charlottesville that was published in the journal EBioMedicine.

Lead researcher Tarek Abbas, assistant professor of radiation oncology, says:

"In fact, the drug is very effective on all melanomas, including those for which an effective therapeutic is lacking."

Melanoma is an aggressive skin cancer that develops when melanocytes - the cells that give skin its color - mutate and become cancerous.

Read more: Melanoma May Be Stoppable With Drug That Halts Cancer Cell Proliferation

Melanoma is an aggressive skin cancer that develops when cells that give skin its color mutate and
become cancerous. The researchers say they have found a drug that may stop the cancer progressing.

Source: MedicalNewsToday

Key to making reversible, non-hormonal male contraceptives!

At last!

Scientists are getting closer to developing a new kind of reversible male contraceptive that doesn't produce any hormonal side effects.

While a commercial drug could still be some way off, the researchers have managed to isolate a key enzyme found only in sperm. Now that they've identified it and can manufacture this enzyme, the team hopes to target it with a range of drug candidates. With the right drug, it should be possible to decrease sperm motility – their ability to swim – which could prevent sperm from egg fertilisation.

"The milestone reached is the production and isolation of a full-length, active kinase enzyme in sufficient quantities to conduct drug screens," said researcher John Herr from the University of Virginia School of Medicine. "Isolation of an active, full-length form of this enzyme allows us to test drugs that bind to the entire surface of the enzyme so that we can identify inhibitors that may exert a selective action on sperm."

The enzyme in question – called testis-specific serine/threonine kinase 2 (TSSK2) – is unique to the testes, and also appears to only be involved in the final stage of sperm production. That's important, the researchers say, because it makes it more likely that any drug candidate that successfully targets the enzyme won't produce any side effects elsewhere in the body.

Read more: Key to making reversible, non-hormonal male contraceptives!

Source: cloudfront