Gene Expression Studies:
Using Prostate Cancer Specimens from Dr. Catalona
by Cecilia Lacks, Ph.D.
Two noted scientists working in Boston are using prostate cancer specimens from Dr. Catalona to further their research.
Todd Golub, M.D. is a specialist in the genetics of cancer at the MIT Center for Genome Research and at the Dana Farber Cancer Institute (DFCI). William R. Sellers, MD, is an expert in the area of prostate cancer biology and tumor suppressor genes at DFCI at Harvard Medical School.
"Golub and Sellers are among the best in the world at doing expression profiling," Dr. Catalona said.
One of their research studies involves the gene expression correlations between those who relapse after initial prostate cancer treatment and those who don't.
Golub explained that he and Sellers want to identify new genes associated with predicting which prostate cancer patients are likely to relapse and which aren't.
They are studying gene expressions in prostate cancer using data sets (from specimens) of patients who had relapses and those who didn't.
"Dr. Catalona's specimens are important because he has such a large data bank of samples," Sellers said.
Sellers explained that gene expression studies are also ways of discovering bio-markers, (PSA is an example of a bio-marker for prostate cancer) which are good for early diagnosis but not for treatment.
"Only if a gene is a driving force behind the tumor will its regulation have theraputic or treatment possibilities," he explained. "And we don't know how to distinguish the two from gene expression studies alone."
Predicting relapses in prostate cancer is only one part of their research. They direct their work to other areas of concern for the treatment of cancers in general and prostate cancers in particular.
The early diagnosis of prostate cancer is possible because of PSA testing, but early diagnosis doesn't help answer significant treatment concerns resulting from the fact that all prostate cancers are not alike.
Some are less or more aggressive than others. Some are more responsive to particular treatment than others. And some need more active intervention than others.
Golub's prediction is that several new rationales for drug designs and prostate cancer treatments are going to result from gene expression studies.
"But managing patients' expectations in regards to these new developments is important," Golub said. "I can't tell patients when these "magic bullets" will be available, but, even now, we could do a lot better in treatment if we had earlier diagnosis and we knew more about the particular prostate cancer of the patient.