BACKGROUND AND OBJECTIVERecent studies indicated that Non-small cell lung cancer (NSCLC) patients with mutant K-RAS failed to benefit from adjuvant chemotherapy, and the cancer did not respond to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs). These findings indicated that K-RAS gene status can be a biomarker to predict the sensitivity of EGFR TKIs. The aim of this study is to analyze K-RAS gene mutations with NSCLC patients in Cancer Center of Sun Yet-sen University.

METHODS52 fresh frozen tumor tissues were collected and K-RAS genes were amplified by PCR. Then PCR amplification fragments were sequenced and analyzed.

RESULTSSomatic mutations in the codon 12 of K-RAS gene in tumors were identified from 2 of 52 (3.8%) patients. There were no relationships among K-RAS gene mutations and gender, pathology, smoking, differentiation and stage.

CONCLUSIONThe frequency of K-RAS gene mutations with NSCLC in our center is very low and is similar to that in Asia patients, and is lower than that in Caucasian population.

Adult ; Aged ; Carcinoma, Non-Small-Cell Lung ; genetics ; Female ; Humans ; Lung Neoplasms ; genetics ; Male ; Middle Aged ; Mutation ; Proto-Oncogene Proteins ; genetics ; Proto-Oncogene Proteins p21(ras) ; ras Proteins ; genetics

BACKGROUNDTissue microarray provides a high throughput tool for protein analysis . The aim of this study is to test the expression of HER2 protein in non-small cell lung cancer (NSCLC) by tissue microarray, and analyze the relationship between HER2 protein expression and chemotherapeutic response rate and survival.

METHODSUsing tissue microarray, HER2 protein expression was detected in patients with advanced NSCLC by immunohistochemistry.

RESULTSTotal 80 patients were enrolled in the study. Only 74 patients could be reviewed for HER2 staining. The response rate to chemotherapy in positive and negative HER2 expression groups was 39.1% and 51.0% respectively (P=0.345). The survival difference was also not significant between the positive and negative HER2 protein expression groups (P= 0.437 ).

CONCLUSIONSThe combination of tissue microarray and immunohistochemistry represents a highly feasible technique for examination of HER2 protein expression in NSCLC. There is no significant difference in survival between positive and negative HER2 expression groups. The role of HER2 protein in NSCLC should be further studied.