Upregulation of sst2 gene expression appears to indicate better prognosis.

2004 SEP 2 - (NewsRx.com & NewsRx.net) -- Upregulation of sst2 gene expression appears to indicate better prognosis in breast cancer patients, suggest researchers at the University of Florence.

"Somatostatin analogs are effective in inhibiting growth of human breast cancer cell lines. These antiproliferative effects are mediated by specific receptors located on cell membranes. The somatostatin receptor subtype 2 (sst2) is the principal mediator of somatostatin effects in normal and cancer cells, and its presence has already been demonstrated in breast cancer," wrote C. Orlando and colleagues.

They "[evaluated] the clinical relevance of the expression of sst2 by quantifying its mRNA in a large group of infiltrating breast cancers and their corresponding normal tissues. The expression of sst2 mRNA was measured with quantitative real time reverse transcriptase polymerase chain reaction in 169 breast cancers and in their corresponding unaffected tissues."

Then "association of sst2 expression with the commonest clinical-pathologic features of breast cancer [and] correlation with a marker of cell proliferation (Ki-67) and with receptor concentration" were determined.

The researchers "found that the absolute concentrations of sst2 mRNA were significantly higher in estrogen receptor (ER)-positive samples (p=.002) as well as in lymph-node-negative cancers (p=.04) (Student Mest or one-way ANOVA)."

"In addition," Orlando and colleagues reported, "sst2 mRNA was significantly higher in breast cancers than in corresponding unaffected tissues (p=.0002).

"However, when the clinical-pathologic parameters were considered, this gradient maintained its statistical significance only in tumors expressing positive prognostic markers, such as the presence of ER (p=.0005) ...