Caspase 3/8/9 Apoptotic Pathway Deregulation Analysis in Laryngeal Squamous Cell Carcinoma

Among the molecules that are implicated in the regulation of apoptosis (programmed cell death), caspases are most significant acting as strong enhancers. The aim of the current study was to co-analyze the caspases 3, 8 and 9 at their protein expression level in a series of laryngeal squamous cell carcinomas (LSCCs).

Tissue specimens derived from 50 LSCC cases were selected and co-analyzed for determining the caspase 3/8/9 expression. A combination of immunohistochemistry and digital image analysis assays was implemented.

According to the analysis of the immunostained slides, females showed higher median expression levels of caspase 3/9 and lower caspase 8 compared to males. However, none of these differences reached statistical significance. Furthermore, median caspase 3 expression levels decreased from Grade 1 to Grade 3, and similar gradual changes were noted for other markers. However, none of these differences reached statistical significance, indicating that the distributions of the biomarkers did not differ significantly by grade. Interestingly, the median caspase 3 levels strongly decreased with stage and this difference was significant (p = 0.033). No significant differences were found across stages for caspase 8/9 and also regarding the anatomical region of the examined tumors.

Deregulation of caspase 3/8/9 molecules that regulate a crucial cataract of reactions in the apoptotic pathway is a relatively frequent event in LSCCs. Progressive loss of their expression is correlated with an aggressive phenotype in the corresponding malignancies, especially referring to caspase 3. Enhancing caspase 3/8/9 expression - that induces apoptotic rates in malignant tumors including LSCC - is a significant goal and challenge for developing novel targeted therapeutic strategies.