Clinicopathologic Significance of Heat Shock Protein 60 as a Survival Predictor in Colorectal Cancer

SIMPLE SUMMARY: HSP60, a mitochondrial chaperone, can promote or inhibit cancer progression. Patients with colorectal cancer (CRC) were examined for HSP60 expression using the TNM classification. Patients with differentiated and p53-mutated CRC expressed high levels of HSP60. Compared with patients with high HSP60 expression, those with low expression had event-free and disease-specific survival hazard ratios of 1.42 and 1.69, respectively. TNM class and HSP60 expression affected survival, especially in late/advanced stages. The expression of the HSPD1 gene, which encodes HSP60, exhibited the same pattern as the protein. The hazard ratios for overall and relapse-free survival were 1.80 and 1.87, respectively, for patients with reduced HSPD1 expression. Low HSPD1 expression and advanced malignancy worsen CRC prognosis. This study suggests that HSPD1/HSP60 may be a useful biomarker for refined survival prediction in late-stage and advanced-stage CRC, allowing for individualized therapy. ABSTRACT: The role of heat shock protein 60 (HSP60), a mitochondrial chaperone, in tumor progression or its anti-tumor effects remains controversial. This study aimed to confirm the possibility of using HSP60 as a prognostic marker in patients with colorectal cancer (CRC), considering TNM classification for precise prediction. HSP60 expression increased with differentiation and p53 mutations in patients. However, compared to patients with high HSP60 expression, patients with low HSP60 expression had event-free survival and disease-specific survival hazard ratios (HRs) of 1.42 and 1.69, respectively. Moreover, when the survival rate was analyzed by combining TNM classification and HSP60 expression, the prognosis was poor, particularly when HSP60 expression was low in the late/advanced stage. This pattern was also observed with HSP family D member 1, HSPD1, the gene that encodes HSP60. Low HSPD1 expression was linked to lower overall survival and relapse-free survival rates, with HRs of 1.80 and 1.87, respectively. When TNM classification and HSPD1 expression were considered, CRC patients with low HSPD1 expression and advanced malignancy had a poorer prognosis than those with high HSPD1 expression. Thus, HSPD1/HSP60 can be a useful biomarker for a sophisticated survival prediction in late- and advanced-stage CRC, allowing the design of individualized treatment strategies.