Gene Expression Signatures in Tumors
All genes are encoded in the DNA stored in the nucleus of each cell in the body. The genes comprise the information for the production of proteins. Proteins come in diverse forms and functions that control all cellular processes, like for example, the question of when a cell multiplies itself through the process of cell division.
Cancer cells bear mutations in genes responsible for growth control, which finally lead to an uncontrolled multiplication of these erroneous cells. The initiating mutations usually lead to a significant difference in the way that all genes on the DNA are used turned on or off, in a cancer cell as compared to a normal cell, that means cancer cells use other genes and some genes to a larger or lesser extent than the normal healthy cells. These differences in gene utilization or expression are finally responsible for the malignant behavior of the cancer cells. With a special method, the so-called microarray analysis, these differences can be measured for all genes on the human DNA. Such measurements allow to determine specific so-called gene expression signatures of tissues. Comparing gene expression signatures of cancer tissue to the signature of normal healthy tissues allows to gain insight into processes that lead to the malignant behavior of the cancer cells. In addition, some of the biological processes overactivated by genes utilized by the cancer cells can be targeted by inhibitory drugs, leading to tumor growth arrest.
The tumor gene expression signatures can also provide information about different subsets of patients who will or will not respond to a certain treatment. Thus, tumor gene expression patterns can help to determine the best treatment for individual patients. This would lead to individually tailored and targeted cancer therapies.
The projects of this module determine the gene expression signatures for different cancer types: For a brain tumor called glioblastoma, for breast cancer, and, in a former project that is since 2008 continued outside of the NCCR program, for the skin cancer called melanoma.