Establishment and Characterization of a Small Cell Lung Cancer Cell Line(JePa-1)

Lee, Mi Ja; Jeon, Ho Jong; Chung, Jong Hoon

Abstract

Lung cancer is the most common malignant tumor worldwide and its incidence continues to rise each year. Recent development of molecular biologic method has led to advances in determining the etiologic factors of lung cancer and the establishment of cell lines has provided a lot of information on the through chemosensitivity, radiation biology studies, cytogenetics, and molecular biologic studies, which permits improved treatment for lung cancer. We established a small cell lung cancer cell line, designated JePa-1, obtained from malignant pericardial effusion of small cell lung cancer patient and characterized its morphologic and molecular biologic features. the JePa-1 cell line grew relatively slowly (doubling time 45hrs) as very loosely adherent floating aggregates growing in small clumps with distinct cell outlines and intertwined cords. Also JePa-1 cell line secreted antidiuretic hormones. Electronmicroscopic examination revealed that JePa-1 cell line and xenografts contained electron dense core granules, characteristic of being of neuroendocrine origin. To investigate the tumorigenic capacity, the JePa-1 cell line was injected into SCID and nude mice. Tumors taken from xenografts were observed in 3 out of 4 of the SCID mice and 2 out of 4 of the nude mice. The histologic characteristics of the xenografts were similar to those of the cell line and the original cytologic finding of the pericardial fluid, suggesting small cell carcinoma. The results of immunohistochemical markers showed reactivity for Rb protein, c-myc, TGF-alpha, TGF-beta , EGFR, keratin, NSE, chromogranin, and EMA. The DNA ploidy and the index of the JePa-1 cells was tetraploid and 2.13, respectively. The positive rate for the Rb, c-myc and K-ras proteins of the JePa-1 cell line were 98.9%, 99.3%, and 99.7% respectively as determined by flow cytometry. Cytogenetic analysis using the G-banding technique showed 65 chromosomes with various numerical and structural abnormalities. On examination of the expression of TGF-alpha, TGF-beta , and EGFR by PCR, only the EGFR was positive Through the establishment of JePa-1 cell line, we report in this paper the characterization of a small cell lung cancer such as morphologic and immunocytochemical features, growth characteristics in culture, hormone production, expression of oncoprotein and several growth factors, tumorigenicity, chromosomal abnormalities, and DNA ploidy and index. The JePa-1 cell line will be valuable in vitro studies for the etiology, treatment and the prognostic factors in small cell lung cancer.