MOLECULAR-GENETICS AND IN-VITRO SENSITIVITY OF A NEW HUMAN CELL-LINE,KKP, FROM A GASTRIC ADENOCARCINOMA

A new cancer cell line (KKP) was established from an ascitic effusion of an advanced gastric adenocarcinoma, intestinal type. The line has b een maintained in continuous monolayer culture with a doubling time of 48 hours for more than 2 years. KKP cells, whose ultrastructural feat ures are presented, showed an aneuploid DNA content, a modal number of 53 chromosomes, and the presence of one double minute chromosome. The karyotype showed trisomies of chromosomes 7, 12, 13, and 14, tetrasom y of chromosome 18, a reciprocal translocation [t(1;201(q21;p11.2)], a nd a [t/4;?)] rearrangement. No amplification or rearrangements were e vident in the c-MYC, c-ERB B2, H-RAS, INT-2, HST-1, c-MOS, and K-RAS g enes, whereas somatic rearrangements were present in the sequences cor responding to c-MET and cyclin E genes by Southern blotting analysis. Polymerase chain reaction-single strand conformation polymorphism (PCR -SSCP) analysis of P53 and RB genes did not reveal alterations or poin t mutations in the SSCP pattern of conformers. The chemosensitivity pa ttern assay of the KKP cell line indicated that it was sensitive to ci splatin, etoposide, and doxorubicin and resistant to 4'-hydroperoxycyc lophosphamide. The clinical history of the patient from whom the cell line was derived is reported and compared with the results observed in the cell line in vitro. High levels of the tumor-associated antigens CEA (carcinoembryonic antigen) and CA19-9 were evident in the KKP cyto sol, whereas the KKP spent culture medium maintained the same low leve ls of CEA and CA 19-9 found in the patient's serum. This new cell line may represent a useful tool for studying the biology of gastric cance r and for planning new therapeutic approaches. (C) Elsevier Science In c., 1998.