BALTIMORE, Nov. 9 (UPI) -- Research conducted by Johns Hopkins Medicine suggests an experimental drug targeting abnormally high levels of a protein linked to cancer growth, specifically RNA helicase DDX3, seems to reduce the spread of prostate cancer cells, while also making the cells more vulnerable to radiation.
In the study, published in the American Association for Cancer Research, researchers found that by specifically targeting and blocking DDX3 -- which is seen in high levels in men with prostate cancer -- the survival and proliferation of cancerous cells is "significantly reduced."
For the study, researchers designed a small molecule, identified as RK-33, that would dock into DDX3's ATP-binding domain, which "perturbed" DDX3's activity. When the prostate cancer cell lines of DU145, 22Rv1, and LNCaP, which all have high levels of DDX3, were treated, RK-33 was able to decrease the proliferation of cancerous cells, while also inducing a G1 phase cell cycle arrest -- meaning a cell did not move past the first of the four phases of the cell cycle.
However, in PC3 -- the cell line in which DDX3 is found in low levels -- few changes were seen after being treated with RK-33.
The study also said that researchers found combination studies that used both the RK-33 molecule and radiation in xenograft and in vitro experiments showed that RK-33 worked as a radiosensitizer, which makes cells more sensitive to radiation therapy.
"Despite advances in diagnosis and treatment, prostate cancer is the most prevalent cancer in males and the second-highest cause of cancer-related mortality in men," the Baltimore-based researchers said in a statement. "Taken together, these results indicate that blocking DDX3 by RK-33 in combination with radiation treatment is a viable option for treating locally advanced prostate cancer."
