Common flaw found in tumor cells

Scientists are finding that at the core of nearly every type of tumor cell, whatever the organ of origin, lies the same terrible flaw.

The flaw afflicts a single gene in the cell, a gene that goes by the humdrum name of p53. So nearly universal is the defect in human tumors that scientists are beginning to suspect that it could be an almost indispensable step in cancerous transformation.

Other genes clearly are mutated in any given cancer. But while some mutations vary from one class of tumor to the next, a blow to the p53 gene could be a common denominator to nearly every malignancy, particularly the most prevalent and deadliest adult tumors.

"This quite clearly is the most commonly mutated gene we've yet found in human cancers," said Dr. Bert Vogelstein of the Johns Hopkins School of Medicine in Baltimore. "The list of tumors that are affected is fairly staggering, and on that basis alone the work is extremely important."

Scientists believe that in its normal state the gene must be central to cellular harmony, and that before a cell can descend into complete chaos, its p53 gene must be corrupted. The gene is mutated in a huge percentage of malignancies of the lung, breast, colon, skin, blood, throat, brain and liver.