Genetic Mutation Increases Prostate Cancer Risk for Small Percentage of Men

Men who inherit a rare genetic mutation have a 10 to 20 times increased risk of developing prostate cancer, according to researchers from John Hopkins University School of Medicine, Baltimore, and the University of Michigan Health System, Ann Arbor.

This mutation is only responsible for a tiny percentage of prostate cancer cases, but the recently established connection can still offer vital information concerning the way cancer develops. It can also aid physicians in identifying a small group of men with the gene who may require early or additional screening.

Researchers conducted the study by first taking samples from the youngest patients with prostate cancer in 94 families who participated in studies at Johns Hopkins and the University of Michigan. They screened genes in the cancer patients and even tested the family members of the cancer patients alongside control subjects to determine the occurrence rate of the identified mutations.

They found that members of four families had the same “rare but recurrent mutation (G84E) in HOXB13 (rs138213197), a homeobox transcription factor gene that is important in prostate development,” the authors write in an abstract. All 18 men with prostate cancer in these families had this mutation.

“The carrier rate of the G84E mutation was increased by a factor of approximately 20 in 5083 unrelated subjects of European descent who had prostate cancer, with the mutation found in 72 subjects (1.4%), as compared with 1 in 1401 control subjects (0.1%),” the authors continued to write.

They also noted that the mutation was observed far more frequently in men who suffered from early-onset (before age 55) prostate cancer with a family history of the cancer (3.1%) in comparison to men with late-onset (after 55) with no family history of prostate cancer (0.6%).

"It’s what we’ve been looking for over the past 20 years," said co-senior author William B. Isaacs, PhD, of Johns Hopkins, according to an article from Modern Medicine. "It’s long been clear that prostate cancer can run in families, but pinpointing the underlying genetic basis has been challenging and previous studies have provided inconsistent results."