Establishment and characterization of a human lung adenocarcinoma cell line (LC‐2/ad) producing α₁‐antitrypsin in vitro

Abstract

A new human cell line, LC‐2/ad was established from pleural effusion of pulmonary adenocarcinoma of a 51 year old Japanese female. The LC‐2/ad cells exhibit an epithelial appearance and a tendency to form small domes as observed with phase‐contrast microscopy. The modal chromosome number was 53–56. Plating efficiency and doubling time were 6.8% and 58 h, respectively (32th passage). Immunocytochemlcally, the cells were strongly positive for CEA and cytokeratins including cytokeratin no. 18 which is present in simple epithella. Ultrastructurally, the cultured cells were characterized by well‐formed junctional complexes and microvilli. Subcutaneous injection of 5 × 106 cells into a nude mouse resulted in tumor formation classified histologically as a moderately differentiated adenocarcinoma. This cell line produced at least two functionally active trypsin inhibitors together with several proteinases in vitro. The main inhibitor was purified partially from the serum‐free conditioned medium and confirmed immunologically as human α1‐antitrypsin (AAT). Immunohistochemically, the xenografted tumor was also positive for AAT. The cell line LC‐2/ad is useful for the study of tumor‐derived serine proteinase inhibitors, in particular AAT.

Identification of a lung adenocarcinoma cell line with CCDC6‐RET fusion gene and the effect of RET inhibitors in vitro and in vivo

“…The original report indicated that the LC-2 ⁄ ad cells were positive for an adenocarcinoma marker, cytokeratin 18. (23) In addition, we detected surfactant protein, an aspartate proteinase, Napsin A, and CEA expression in the xenograft tumor (Fig. 4a).…”

“…LC2 ⁄ ad cells at 5.0 9 10 6 were subcutaneously inoculated to 8-week-old athymic nude mice (Clea Japan). (23) Vandetanib was administered once daily as a homogeneous suspension by oral gavage at a dosage of 50 mg ⁄ kg body weight. (24) The tumor volume was calculated as the product of a scaling factor (p ⁄ 6) and the tumor length, width and height.…”

Emerging multifunctional aspects of cellular serine proteinase inhibitors in tumor progression and tissue regeneration

“…Similar findings have been reported by a number of other research groups. These SPI include α1‐proteinase inhibitor (αPI), 16–21 α1‐antichymotrypsin (αACT), 9 plasminogen activator inhibitor (PAI)‐1 and PAI‐2, 19,22 squamous cell carcinoma (SCC) antigen, 23 pancreatic secretory trypsin inhibitor (PSTI), 24,25 amyloid β protein precursor (APP), 26–29 tissue factor pathway inhibitor (TFPI)‐1 and TFPI‐2, 30,31 secretory leukocyte proteinase inhibitor (SLPI) 31,32 and hepatocyte growth factor activator inhibitor type 1 (HAI‐1) 33,34 and HAI‐2 35–37 . These SPI can be classified into several subgroups according to their molecular structures and mechanisms of proteinase inhibition: (i) serpin‐type SPI, such as αPI, αACT, PAI‐1, PAI‐2 and SCC antigen; (ii) Kunitz‐type SPI, such as APP, TFPI‐1, TFPI‐2, HAI‐1 and HAI‐2; (iii) Kazal‐type SPI, such as PSTI and SLPI.…”

Molecular mechanisms underlying human β‐defensin‐2 gene expression in a human airway cell line (LC2/ad)

“…In the current study, we examined the molecular mechanisms of hBD‐2 expression in vitro . To perform the present study, we used a human airway cell line, LC‐2/ad, which was established from pleural effu‐sion of pulmonary adenocarcinoma and exhibits an epithelial appearance 14 …”