*, P < 0.01. Expression of SOX9 protein and histological staging of NSCLC Immunostaining examination of tumor sections obtained from 142 patients showed that positive SOX9 BVD-523 expression was found to be correlated strongly with the clinicopathological stages of the patients’ cancer (P = 0.022), but no significant relationship was found between age (P = 0.382) or gender (P = 0.240), or pathology (P = 0.312) (Table 2). Spearman correlation analysis revealed a correlation coefficient of 0.200 (P = 0.017; Table 3) between SOX9 expression level and the
histological grading of NSCLC. Taken together, these observations support the notion that the progression of NSCLC is associated with increased SOX9 expression. Table 2 Correlation between the clinicalpathologic features and expressions of SOX9 Characteristics SOX9 P-value Low or none High Gender 0.382 Male Female 47 21 56 18 Age (years) 0.240 ≤ 65 >65 46 22 43 31 Pathology Squamous cell carcinoma 26 21 0.312 Adenocarcinoma 32 36 Adenosquamous carcinoma 10 17 NSCLC histology (AJCC grade) 0.022 I and II III and IV 34 34 23 51 Survival (n = 89) 0.040 Alive Dead 21 23 12 33 Table 3 Spearman correlation analysis between SOX9 and clinical pathologic factors Variables SOX9 Spearman Correlation P -Value Gender -0.083 0.325 Age 0.098 0.247 NSCLC histology (AJCC grade) 0.200 0.017 Survival RG7204 chemical structure -0.239 0.024 Association between SOX9
expression and patient prognosis The statistical analysis presented in Table 2 revealed an inverse correlation between SOX9 level and patient survival (P = 0.040). Spearman
analysis also showed a correlation coefficient of -0.239 (P = 0.024; Table 3) between SOX9 and patient survival. Log-rank Rapamycin test and Kaplan-Meier analysis were also applied to evaluate further the effect of SOX9 expression and histological staging of lung cancer on survival. The log-rank test showed that the expression level of SOX9 protein in NSCLC was correlated significantly with patients’ survival time (P < 0.001), with a correlation coefficient of -0.262 (Figure 4; Table 4). As shown in Figure 4, the cumulative 3-year survival rate was 65.9% in the low-SOX9 expression group (n = 44), and 24.5% in the high-SOX9 expression group (n = 45). The multivariate survival analysis shown in Table 4 indicated that SOX9 expression level was an independent prognostic factor in the assessment of patient outcomes. Figure 4 Kaplan-Meier curves with univariate analyses (log-rank) for patients with low SOX9-expressing (bold line) versus high SOX9-expressing tumors (dotted line). The cumulative 3-year survival rate was 65.9% in the low SOX9 expression group (n = 44), whereas it was only 24.5% in the high SOX9 expression group (n = 45). Table 4 Univariate and multivariate analysis of different prognostic parameters in patients with NSCLC by Cox-regression analysis Univariate analysis Multivariate analysis No.