Establishment, characterization, karyotyping, and comparative genomic hybridization analysis of HKESC-2 and HKESC-3: two newly established human esophageal squamous cell carcinoma cell lines

The establishment of esophageal cancer cell lines can facilitate the search for molecular mechanism underlying its pathogenesis. Two novel human esophageal squamous Cell carcinoma (ESCC) cell lines. HKESC-2 and HKESC-1. were established from a moderately differentiated ESCC of a 46-year-old Chinese woman and a well-differentiated ESCC of a 74-ycar-old Chinese man, both from Hong Kong. The pathological characteristics (morphological, immunohistochemical. and electron microscopic studies). tumorigenicity in nude mice, cytogenetic features, and DNA ploidy of the two cell lines were investigated. The two cell lines have been maintained in vitro for more than 17 months and passaged over 85 times for HKESC-2 and 58 times for HKESC-3. Both grew as monolayers, with a doubling time of 24 hours for HKESC-2 and 48 h for HKESC-3. Their squamous epithelial nature was authenticated by their strong immunopositivity with the anti-cytokeratin antibodies and the ultrastructural demonstration of tonofilaments and desmosomes. They are tumorigenic in nude mice and had DNA aneuploidy. G-banding cytolgenetic analysis showed hyperdiploidy in HKESC-2 and near-tetraploidy in HKESC-3. Frequent breakpoints were noted at 1p22, 1p32. and 9q34 in HKESC-2 and at 1p31, 3p25, 3p14 6q16. 6q21. 8p21. 9q34. 13q32, and 17q25 in HKESC-3. Comparative genomic hybridization analysis found that chromosomal gains were at 3q24similar toqter, 5q21similar toqter, 8q11similar toqter, 13q21similar toq31 17q11similar toqter, 19, 22q22 for HKESC-2 and at 3q13-qter. 5p 6p, 9q21similar toqter, 10q21similar toq22 12q15similar topter. 14q24similar toqter, 16, 17q24similar toqter 20 for HKESC-3. Chromosomal losses were at 3p13similar topter, 18q12similar toqter for HKESC-3. These two newly established cell lines will be useful tools in the study of the molecular pathogenesis and biological behavior of ESCC cells and for testing new therapeutic reagents for ESCC in the future. (C) 2002 Elsevier Science Inc. All rights reserved.