Among the highlights in the August 1998 Cancer Watch issue are: Urokinase Plasminogen Activator (uPA) - Another Target for Preventing Cancer Spread, Cancer Risk Among Offspring of Childhood-Cancer Survivors, Compound Present in Tree Bark Induces Apoptosis, Increased Incidence of Blood Cell Cancers Among Meat Industry Workers, Radioiodine Treatment for Hyperthyroidism Does Not Increase Total Cancer Death, Characteristics of BRCA1- and BRCA2- Associated Breast Cancer, High Bone Density and Risk of Breast Cancer, Drugs for Osteoporosis Prevent Breast Cancer Metastasis, Oral Contraceptive and Hereditary Ovarian Cancer, Postoperative Radiotherapy for Lung Cancer, Selenium and Risk of Prostate Cancer, New Approaches in the Treatment of Cancer, Angiostatin as a Radiation Modifier, Electroporation Therapy Marches On and Molecular Basis of Breast Cancer and its Treatment.

News in Brief

• Urokinase Plasminogen Activator (uPA) - Another Target for Preventing Cancer Spread
• Cancer Risk Among Offspring of Childhood-Cancer Survivors
• Compound Present in Tree Bark Induces Apoptosis
• Increased Incidence of Blood Cell Cancers Among Meat Industry Workers
• Radioiodine Treatment for Hyperthyroidism Does Not Increase Total Cancer Death

• Important differences exist between the breast tumors associated with mutation of BRCA1 and BRCA2 genes and identification of the variance will improve the classification of tumors in patients with a family history of breast cancer.

• High bone mineral density, especially in postmenopausal women with family history of breast cancer may increase the risk of breast cancer.

• A class of compounds known as bisphosphonates are in wide current use to prevent osteoporotic bone loss. They inhibit bone resorption probably by inhibiting the activity of osteoclasts, the cells that participate in bone removal. Now it has been demonstrated that early use of certain bisphosphonate may reduce metastatic tumor burden, both in bones and soft tissue.

• The use of oral contraceptives may reduce the risk of ovarian cancers inherited due to BRCA1 or BRCA2 gene mutations.

• Postsurgical radiotherapy of early-stage non-small-cell lung cancer reduces survival chance of many patients. This adverse effect may be due to complications that develop from radiation and not from cancer.

• In a prospective study it has been recently demonstrated that daily supplementation of 200 µg selenium significantly reduces risk of prostate cancer. Further study showed that men who had a higher level of long-term selenium intake had a reduced risk of developing advanced prostate cancer compared with men who had lower levels.

• During the recent Annual Meeting of the American Society of Clinical Oncology several new treatment approaches for a variety of major cancers in advanced stages were discussed. For hormone-refractory prostate cancer suramin plus hydrocortisone was found to be beneficial. For metastatic colorectal cancer the drug irinotecan extended survival.

• Angiostatin, a natural product, which was first isolated from serum and urine of tumor-bearing mice, is found to improve therapy when used in combination with radiation targeted to neovasculature of growing tumors.

• Electroporation, a physical technique that transiently destabilizes the cell membrane making it permeable to otherwise impermeable agents, has great potential in cancer therapy. It can be employed not only to augment the effective drug concentration in tumors but also for high efficiency in vivo gene transfer.

• Effective treatment for any disease can be delivered if the underlying cause at the molecular level is known and the technology is sophisticated enough. Unlike many diseases, countless molecular events are associated with cancers and researchers are painstakingly delineating them. Though only occasionally there is excitement about one or two discoveries that make news paper front page or evening news, enormous amount of basic research has paved the path to reach that level and these data add critical information to our understanding of the disease. It seems very reasonable to believe that future treatment of cancer will be based on molecular medicine.

• The BRCA1 gene, mutation of which increases the risk of breast and ovarian cancer, encodes a protein which participates in the repair of oxidative DNA damage. In the absence of this protein oxidative damage could lead to inefficient transcription and accumulation of mutations in genes, leading to uncontrolled growth in cancer.

Glossary

• A glossary of unfamiliar words and jargons in Cancer Watch, August1998.