• DNA carries the blueprint of life. Changes at critical sites can create disorder. And it is so easy to damage the DNA. However, there are pathways that sense this damage and trajectories that carry out the job of correcting the injury. Scientists are slowly unraveling the mechanisms underlying these complex biological processes by studying genetically inherited diseases that show abnormality in DNA damage repair.

• Lifestyles and other confounding factors may account for the high risk of certain diseases in women with silicone implant for breast augmentation.

• Data from two clinical trials show anastrozole (Arimidex, Zeneca), an aromatase inhibitor, to offer a significant survival advantage over megestrol (Megace, Bristol-Myers Squibb) a commonly used progestin, for postmenopausal women with advanced breast cancer. This drug does not have any intrinsic hormonal property, and no hormone-related side effects were reported.

• Most cancer cells show telomerase activity while normal cells, except for those in the germline, do not express telomerase. This test is very simple, specific, and inexpensive and can be adopted for screening and follow-up of many cancers especially bladder cancer where cancer cells can be obtained in voided urine making the procedure totally noninvasive.

• Kaposi's sarcoma, a vascular malignancy of bluish-red nodules or patches on skin surface, found to arise almost synchronously in certain AIDS patients, may not spread from the primary tumor but may originate from a single clone of progenitor cells prominent in the lesions. Certain changes may produce this clonal outgrowth of spindle cells, which then circulate through blood stream and settle at multiple sites to produce tumor.

• The system PAPNET (Neuromedical Systems Inc., Suffern, NY), a highly sophisticated neural network computer scanning system is designed to assist the trained cytotechnologists by searching through the 100,00 - 300,000 cells on a typical Pap smear and singling out and displaying possibly abnormal cells or cluster of cells. Significant percentage of biopsy specimens initially classified as normal were found to be abnormal by PAPNET testing.

• Usually the intravenous formulations of the drug granisetron hydrochloride (Kytril, Smith-Kline Beechum), and ondansetron hydrochloride (Zofran, Cerenex) are thought to be better than tablets for controlling chemotherapy-induced nausea and vomiting. However, the oral formulation of these drugs now available, gives the patients more control over their treatment. The can take a tablet prior to chemotherapy to prevent this problem.

• Thalidomide treatment is shown to have healing effect on severe mouth and throat ulcers of advanced HIV-infected patients.

• A new cancer approach called "antisense" therapy shows promise in inhibiting production of proteins associated with the cancer growth. Antisense therapy introduces strands of manufactured DNA (antisense) designed to bind to and inactivate strands of messenger RNA (sense) that produce proteins linked with cancer. Early results from a small human trial show the treatment can be effective in various cancers and is safe. Another study indicates that families in which one woman develops breast cancer before the age of 50 and another has ovarian cancer have a significantly increased risk of carrying mutated BRCA1 gene. Breast cancer patients expressing Her-2 protein have poor prognosis than those patients who do not express this protein.

Glossary

• A glossary of unfamiliar words and jargons in Cancer Watch, January-June 1997.