Scientists Starve Prostate Tumors Of Leucine To Slow Growth

Researchers at the Centenary Institute in Sydney have found that prostate cancer cells have more pumps for the essential nutrient leucine, revealing a potential target for treatment through starving these tumor cells.

AsianScientist (Nov. 14, 2011) – Led by Dr. Jeff Holst and his team at the Centenary Institute in Sydney, researchers have found that prostate cancer cells have more pumps for the essential nutrient leucine, revealing a potential target for treatment through starving these tumor cells.

Each year about 3,300 Australian men die of prostate cancer. It is the most common cancer in Australian men and the second worst cancer killer for men, matching the impact of breast cancer on women.

Current therapies for prostate cancer include surgical removal of the prostate, radiation, freezing the tumor, or cutting off the supply of the hormone testosterone. However, there are often side effects including incontinence and impotence.

In a research paper published in the journal Cancer Research, prostate cancer cells were found to have more pumps than normal, which allow the cancer cells to take in more leucine and outgrow normal cells.

Uinsg this information, Dr. Holst and his team targeted these pumps to starve prostate cancer cells grown in the lab.

“We’ve tried two routes,” he explained. “We found that we could disrupt the uptake of leucine firstly by reducing the amount of the protein pumps, and secondly by introducing a drug that competes with leucine. Both approaches slowed cancer growth, in essence ‘starving’ the cancer cells.”

First author Dr. Qian Wang says the researchers were able to slow tumor growth in both the early and late stages of prostate cancer by targeting different sets of pumps.

“In some of the experiments, we were able to slow tumor growth by as much as 50 percent,” said Dr. Wang.

The team hopes to develop a treatment that slows the growth of the cancer so that it would not require surgical removal. If animal trials are successful over the next few years, Dr. Wang anticipates starting clinical trials in as little as five years.

Dr. Holst points out that the discovery also provides a better understanding of the links between prostate cancer and a high leucine diet. Diets high in red meat and dairy are correlated with prostate cancer, he said, though the reason is unknown. His team has begun examining whether the pumps can explain the links between diet and prostate cancer.

“Given one in nine men in Australia may develop prostate cancer in their lifetime, this discovery could touch thousands of lives,” he said.

The study was funded by the Prostate Cancer Foundation of Australia (PCFA) and the Movember Young Investigator grant. This publication is just in time for Movember, a month-long charity drive in which thousands of people around the globe grow moustaches to raise money for men’s health issues including prostate cancer.

The article can be found at: Wang Q et al. (2011) Androgen receptor and nutrient signaling pathways coordinate the demand for increased amino acid transport during prostate cancer progression.

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Source: Prostate Cancer Foundation of Australia.
Disclaimer: This article does not necessarily reflect the views of AsianScientist or its staff.

Grace Liao received a SB degree in chemical-biological engineering from the Massachusetts Institute of Technology (MIT), USA.

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