Prognostic prediction of the immunohistochemical expression of p53 and p16 in resected non-small cell lung cancer.
OBJECTIVE
p53 and p16(INK4) are the common and important tumor suppressor genes. Aberrant expression of p53 or p16 protein has been reported in various malignancies including lung cancer. Our aim was to investigate the association of p53 and p16 expression in resected non-small cell lung carcinoma (NSCLC) and evaluated their correlation with clinocopathologic features and survival.


METHODS
p16 and p53 expression were detected by immunohistochemical analysis of 90 paraffin specimens of resected NSCLC, including 35 squamous cell carcinoma, 47 adenocarcinoma, and eight large cell carcinoma, between stages I and IV. The immunohistochemical study was performed using the labeled streptavidine-biotin method with anti-p53 and anti-p16 monoclonal antibodies.


RESULTS
Fifty-two (57.8%) and 36 (40%) of 90 patients revealed aberrant immunostaining for p53 (p53+) and p16 (p16+), respectively. While 19 cases (21.1%) showed abnormal immunoreactivity for both p16 and p53. (p53+/p16+). There was no correlation of p53 or p16 expression with the clinicopathologic features. The Kaplan-Meier survival analysis demonstrated that patients with p16+, p53+, late stages, and nodal or distal metastasis had poor survival status (P = 0.006, 0.013, <0.001, <0.001 and 0.018, respectively). Further analysis demonstrated that p53 status was a significant prognostic factor in stage I NSCLCs (P < 0.001), and p16 status in stage I and II NSCLCs (P < 0.001, P = 0.003, respectively). Furthermore, patients whose tumors were both p53 and p16 aberrant expression had worse outcome compared with those whose tumors were both normal expression of p53 and p16 (5-year survival rate: 5 vs. 76%, P < 0.001). In Cox's regression model, the aberrant expression of p16, p53, advanced stages and combined aberrant expression of p53/p16 survived for a significant shorter period.


CONCLUSIONS
The results indicated that aberrant expression of p16 and p53 are significant and independent, predictable prognostic factors for resected NSCLC, especially in early stage of NSCLCs. The worst prognosis was seen in patients whose tumors had both aberrant expression of p53 and p16. Further prospective trials may be aimed at confirming and validating these results.
Cheng
Yeung-Leung
YL
Division of Thoracic Surgery, Department of Surgery, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan, ROC.
Lee
Shih-Chun
SC
Harn
Horng-Jyh
HJ
Chen
Cheng-Jueng
CJ
Chang
Yue-Cune
YC
Chen
Jen-Chih
JC
Yu
Cheng-Ping
CP
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis* / Q000401:mortality; D016009:Chi-Square Distribution; D019941:Cyclin-Dependent Kinase Inhibitor p16 / Q000032:analysis*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000401:mortality; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D016019:Survival Analysis; D016159:Tumor Suppressor Protein p53 / Q000032:analysis*
D019941:Cyclin-Dependent Kinase Inhibitor p16; D016159:Tumor Suppressor Protein p53