The limitless of self-renewal and replication of
cancer cells, one of cancer hallmarks, is supported
by various molecular mechanisms. Overexpression of
cyclins and cyclin-dependent kinases, a group of cell
cycle machinery proteins, is one of the underlying
mechanisms that promotes cell proliferation in several
cancers, especially in breast cancer. Breast
cancer is the highest prevalent cancer among female
patients in Thailand and globally. Many studies revealed
the overexpression of cyclin D1, a partner of
cyclin-dependent kinase 4/6 (CDK4/6), in more than
30% of breast cancer cases. These proteins are indicated
to be essential for survival of breast cancer
cells but are disputable for normal mammary cells.
These findings, thus, led to the development of
CDK4/6 inhibitors which arrest the cell cycle at G1
phase and inhibit cell division. These inhibitors have been tested for their efficacy both preclinical studies
in breast cancer cells and clinical trials in breast cancer
patients. Patients who supplemented with these
drugs had almost double longer survival times compared
with those who received the placebo. The
efficiency of CDK4/6 inhibitors, hence, urged the approval
and implementation of the CDK4/6 inhibitors
into the clinical practice. The discovery of CDK4/6
inhibitors is one of the successful translations of basic
medical research to the clinical study which finally
implemented in the clinical practice of breast cancer
treatment at present.
Keywords
Breast cancer; cell cycle; cyclin; cyclin dependent kinase