On the one hand, the pooled HR for 1-year OS based on two included studies (Malusecka et al. 2008; Tsai et al. 2014) was 0.885 (95 % CI 0.140–5.599; P = 0.896; I2 = 91.5 %, p = 0.001; Fig. 4a; Table 3), indicating that there was no significant correlation between HSP27 expression and 1-year OS of NSCLC. This evidence concerns the gene HSPB1 and non-small cell lung carcinoma.