Establishment and expression profiling of new lung cancer cell lines from Chinese smokers and lifetime never-smokers.

Background: Bronchogenic adenocarcinoma is the predominant histologic subtype of lung cancer, which ranks top in the cancer mortality in both men and women. Female nonsmokers and adenocarcinoma have emerged as a distinct combination in patients with lung cancer in recent decades. Lung cancer cell lines established from patients with known clinical characteristics such as gender and smoking habit would be useful for future research on lung cancer.

Methods: Four new lung adenocarcinoma cell lines (HKULC 1-4) were established from Chinese patients with primary lung adenocarcinomas and with different clinical characteristics with respect to age, gender, smoking habits, tumor staging, and previous therapy. They were characterized by immunohistochemical and growth kinetic studies, tests for tumorigenicity in nude mice, epidermal growth factor receptor (EGFR) gene mutation analysis, and in situ hybridization, and gene expression profiling with Affymetrix GeneChip HG-U133A.

Results: The newly established HKULC lung adenocarcinoma cell lines were maintained for over 70 passages and demonstrated morphologic and immunohistochemical features and growth kinetics of tumor cell lines. One of the four HKULC cell lines, HKULC 3 (derived from a female nonsmoking patient with lung adenocarcinoma), was found to have a deletion at exon 19 of the EGFR gene. EGFR in situ hybridization showed no EGFR gene amplification in these cell lines. HKULC 1 and 4 formed tumor xenografts after inoculation in nude mice. A list of 71 genes that were differentially expressed or showing class predictive significance was identified. These genes included putative tumor suppressor genes (DKK3, SERPINF1, CDH11, DSC3, and KLF6), genes involved in or related to the EGFR pathways (ERBB3, MUC1, VAV1), genes involved in regulation of cell cycle and proliferation (CDKN1A and CDKN2A), a putative oncogene (EEF1A2), and a gene related to metastasis (MTSS1).

Discussion: Four new lung adenocarcinoma cell lines were established from patients with different clinical characteristics. These characterized cell lines and their gene expression profiles will provide resources for studies of lung cancer biology and in vitro chemotherapeutic drug study.