Breast cancer genes suggest new drug targets
genes in non-cancerous supporting cells that can encourage the
growth of breast cancer cells. The findings suggest aiming
chemotherapy at both normal and cancer cells might improve breast
cancer treatment.
The scientists singled out two such genes, CXCL12 and CXCL14, as potential targets for drug therapy. Scientists discovered that the genes contain the genetic code for chemokines, proteins that can prompt cancer progression.
Dr. Kornelia Polyak, the study's senior author told DrugResearcher.com: "The gene CXCL12 was targeted as it displayed high differential expression in breast cancer. We also know that CXCL14 is involved in metastasis (spread of cancer from one part of the body to another)."
The findings also suggest that targeting treatment at both cancer cells and their genetically normal cellular "microenvironment" might improve the success of breast cancer treatment.
Chemotherapy is designed to kill malignant cells in tumours that develop from the lining, or epithelium, of the breast's milk ducts. But under prolonged assault by chemotherapy agents, these cancerous epithelial cells often undergo genetic mutation that makes them resistant to the drugs that previously were killing them. Drug resistance often halts successful treatment for breast cancer.
Polyak said: "The problem of drug resistance in breast cancer is a serious one. This research aims to find factors released by surrounding stromal cells that support the growth of the tumour and target these components with cancer drugs, it might be more effective than targeting the tumour cells alone."
Currently, physicians are not directing therapy at stromal cells - except for antiangiogenic drugs that target the blood vessels that surround and nourish tumours.
One potential benefit of the new gene survey could be a way to detect a gene activity "signature" in ductal carcinoma in situ (DCIS) - an early, precancerous condition - and present in full-blown cancer, to predict how likely they are to progress to invasive cancer. Such a test, not available now, might save some women from needlessly aggressive treatment.
Every year there are 200,000 cases of breast cancer in the US. The rate of incidences is neither decreasing nor increasing having levelled out in the past few years. Advanced mammogram screening has led to a halt in the number of cases.
