Alterations in cell cycle progression, high rates of cell proliferation and chromosomal instability are common features of multiple tumors. Numerous cell cycle regulators are overexpressed in tumors and very often this correlates with poor clinical prognosis. Nevertheless, proper identification of reliable biomarkers related to cell cycle, which not only correlate to prognosis but also provide a therapeutic value, is still lacking.

Classical chemotherapy, although effective in a percentage of cases, is associated with severe cytotoxic side effects. As an alternative, pharmaceutical companies are developing new inhibitors against specific molecular targets of high therapeutic value. Unfortunately, the newly designed drugs, although effective in certain types of tumors are not as efficient as initially thought. Therefore, to increase the knowledge about the molecular basis of certain tumors, as well as to identify mechanisms of sensitivity and resistance to newly developed drugs, is of great interest to the medical community and for upcoming cancer patients.