Heat shock protein 70 is a useful marker for predicting colorectal cancer.

PURPOSE In colorectal cancer (CRC), as in most of other malignancies, heat shock proteins (HSPs) are overexpressed and are associated with apoptosis, cancer cell proliferation, differentiation, invasion, and metastasis. HSP70 is one of the HSPs and has a promising future in cancer studies for both diagnostic and therapeutic applications. In this study, we tried to evaluate the serum levels of HSP70 in CRC patients, and to evaluate its predictive value of detecting CRC. METHODS This prospective study was consisted of 33 patients diagnosed with CRC and 31 healthy subjects who were matched for age. Enzyme-linked immunosorbent assays (ELISA) were used to evaluate the serum levels of HSP70 in patients with CRC and in the healthy control group. A cut-off value for HSP70 was also determined using receiver operating characteristic (ROC) curve analysis. RESULTS Patients with CRC had significantly higher HSP70 concentrations compared with the control group (4.52 ± 1.83 vs 1.22 ± 0.48 ng/ml, p=0.001), the cut-off value was ≥2.25 ng/ml (95% CI 0.993-1.003, p<0.001). The sensitivity and specificity of elevated serum HSP70 in the CRC group were 96.77 and 96.96%, respectively. Also, HSP70 levels were significantly higher with rectal disease localization (p=0.01). CONCLUSION This study shows that the serum level of HSP70 is elevated in patients with CRC. HSP70 may be utilized as an adjunct to other diagnostic or screening tests.