The largest analysis so far of DNA copy-number differences in human cancers has pointed to some potentially important shared features among different tumors (Nature, Feb. 18, 2010: 899-905).

Cancer cells are notorious for carrying many DNA alterations. Copy-number differences are one type of DNA alteration: here, certain parts of a tumor’s DNA may contain too many copies of a DNA region, while, in other parts, important DNA regions are deleted.

In this intriguing new study, the researchers looked at more than 3,000 cancer specimens from 26 types of tumors. They found that the most significant copy-number alterations tend to be found among multiple cancers. This supports growing evidence that the diversity seen in cancer genomes may stem from combinations of features, rather than the total number of features.

Specifically, the scientists found 158 DNA regions where copy-number variations were seen across multiple tumor types. Notably, many of these regions contain genes that are members of families that are already known to be important for cancer drug development, including the BCL2 family of apoptosis regulators and the NF-kB pathway. The researchers also looked at cancer cells with amplifications (multiple copies of a gene) surrounding the MCL1 and BCL2L1 anti-apoptotic genes. They found that cells with those types of copy variations depended on MCL1 and BCL2L1 for survival.