TriStar Enables Gene Finding That Could Lead to Personalized Breast Cancer Treatment

LOS ANGELES - According to TriStar Technology Group, the results of a genetic study could have major implications in the treatment of breast cancer.

The research, carried out using TriStar’s high throughput tissue analysis platform and conducted by its collaborator, the University Medical Center Hamburg-Eppendorf (UKE), Germany, discovered that a fifth of women with breast cancer carry extra copies of a particular gene (ESR1) -- a finding that could, one day, lead to personalized treatment for the potentially deadly disease.

The study, “Estrogen receptor alpha (ESR1) gene amplification is frequent in breast cancer and predicts response to tamoxifen”, co-authored by Ronald Simon, UKE’s/TriStar’s Head of Molecular Pathology, and Guido Sauter, TriStar’s Co-Founder and Chief Scientific Officer, found that 20 percent of breast cancer patients carry extra copies of a gene called ESR1 (estrogen receptor alpha), and that such patients are more likely to respond positively to the widely-used estrogen blocking drug tamoxifen than are patients who do not carry extra copies of the gene.

“The findings of this study could lead to genetic tests to determine when and whether tamoxifen should be prescribed as an effective breast cancer treatment,” said Simon. “The findings also suggest that tamoxifen might, one day, replace or diminish the need for chemotherapy in some women.”

Sauter commented, “Because the gene is amplified in women with certain pre-cancerous conditions, tamoxifen might also help prevent breast cancer from developing in women showing its early signs.”

Milan Bhagat, TriStar’s president, added, “We are very pleased that the UKE team was able to leverage the unique capabilities of TriStar’s high throughput tissue analysis platform and our corresponding library of tissue samples to rapidly generate accurate data relating the frequency of ESR1 amplification to prognosis and response to tamoxifen. This further validates the fact that our unique, high-density prognosis arrays can rapidly and effectively be used to generate immensely valuable intellectual property early in the drug discovery process.”

The TriStar high throughput tissue analysis platform enables researchers to rapidly screen genes against thousands of tissue samples, representing numerous types of cancers, to identify genetic markers, validate drug targets that cause disease and correlate clinical (prognosis) data thereby accelerating the development of new and safer drugs.

Using Affymetrix 10K SNP array to screen for gene copy number changes in breast cancer tissues collected from patients in Germany and Switzerland, the researchers detected amplification of the ESR1 gene. They then conducted high-density tissue microarray analysis on more than 2000 micro arrayed clinical breast cancer samples from TriStar’s repository, and found amplification in more than 20 percent of breast cancers. Ninety-nine percent of tumors with ESR1 amplification showed estrogen receptor protein over-expression, compared with 66.7 percent cancers without such amplification.

In a subsequent study of 175 breast cancer patients who received tamoxifen, survival was significantly higher in those individuals with ESR1 amplified cancers than in those with ER (protein) positive cancers without amplification. An additional finding -- of ESR1 amplification in benign and pre-cancerous breast diseases -- suggests that ESR1 amplification may be a common mechanism in breast disease and an early genetic alteration in many types of breast cancer.