Purpose: Increasing experimental evidence indicates that abnormal expression of c-kit may be implicated in the pathogenesis of a variety of solid tumors. It has been reported that over 70% of small cell lung cancer (SCLC) contain the c-kit receptor. In the present study, a c-kit analysis has been extended to non-small cell lung cancer (NSCLC). The expressions of p53, vascular endothelial growth factor (VEGF) and cd34, in addition to c-kit, were evaluated to investigate the correlations between these proteins and to determine their potential relationships with the clinicopathological data.
Materials and methods: Paraffin-embedded tumor sections, obtained from 147 patients with NSCLC, were immunohistochemically investigated using anti-c-kit, anti-p53, anti-VEGF and anti-cd34 antibodies.
Results: c-kit was expressed in 40 (27%) of the tumors examined: 27% of the adenocarcinomas, 27% of the squamous cell carcinomas and 29% of the undifferentiated carcinomas. p53 and VEG F immunoreactivities were present in 107 (73%) and 110 (75%) carcinomas, respectively. Anti-cd34 was negative in all samples. No associations were established among these proteins. The c-kit, however, showed a strong correlation with the T factor: T1 (n=11), 0%; T2 (n=49), 16% and T3 (n=87), 37% (p=.006).
Conclusion: It is suggested that in NSCLC c-kit is expressed relatively frequently and may become a therapeutic target for the patients with inoperable or recurrent c-kit positive tumors. The alterations in p53 probably constitute an early event, whereas the activated c-kit may contribute to tumor progression.
Keywords: Immunohistochemistry; Non-small cell lung cancer; Vascular endothelial growth factor; c-kit; cd34; p53.