Yegane Zahiri,1,*Roghayeh Gholizadeh Doran Mahalleh,2
1. Medical student, member of Young and Elite Researchers Club of Islamic Azad University, Zahedan, Iran 2. Department of laboratory sciences, Zahedan branch, Islamic Azad university, Zahedan, Iran
Introduction: Escape from apoptosis is one of the six symptoms of cancer. Tumor cells produce many messages, such as a response to DNA damage or oncological activation, that naturally induce apoptosis. Most of the cells that acquire cancerous characteristics are killed by apoptosis through tumor suppression pathways. However, tumor cells that acquire the mutations needed to escape the apoptotic response survive and proliferate. Apoptosis causes more mutations to accumulate. This draws our attention to the differences between tumor cells and normal cells.
Methods: In this review study, Iran Medex, Scopus, Pubmed, Web of Science, Google Scholar, Magiran and SID databases were used.
Results: Compared to healthy cells, tumor cells receive messages that induce apoptosis (such as oxidative stress and oncogen activation), but are more limited in triggering an apoptotic response than healthy cells. Because the apoptotic pathway is often defective in tumor cells. Due to the exposure of cancer cells to different stresses between cancer cells and healthy cells, there is a fundamental difference in the status of caspase activation. In summary, apoptotic messages stimulate the processing of precapsases in healthy cells, while apoptotic messages in cancer cells activate the cessation of the inhibitory effect of IAP on processed caspases. If the apoptotic pathway is efficient, initiating an apoptotic response in a tumor cell is more specific than in a healthy cell.
Conclusion: Apoptosis is an important mechanism of tumor suppression. Caspases Aspartate proteases are major molecular actors in the process of apoptosis. Apoptosis is triggered by extracellular death messages or internal stimuli, which act through external and internal pathways, respectively. Escape from apoptosis is a hallmark of cancer cells.