TRYPSINOGEN EXPRESSION BY 2 HUMAN PANCREATIC-CELL LINES CFPAC-1 AND CAPAN-1 - MODULATION DURING SPONTANEOUS AND INDUCED CELL-GROWTH

We previously demonstrated that two human pancreatic adenocarcinoma ce ll lines, CFPAC-1 (established from a patient with cystic fibrosis) an d CAPAN-1, were able to secrete trypsinogens 1 and 2 specifically. In order to analyze the relation of trypsin secretion to differentiation and cell growth, we undertook a comparative study of immunoreactive tr ypsin 1 (IRT) secretion by the two cell lines during cell growth in th e presence and in the absence of various differentiating agents: sodiu m butyrate (NaBut), dimethylsulfoxide (DMSO), and dexamethasone (DX). In the presence of NaBut, IRT levels in the supernatants of both cell lines were slightly increased, whereas the cellular growth of both cel l lines decreased significantly. In the presence of DX, IRT levels in cell culture conditioned media immediately and dramatically decreased, but the cell growth of neither cell line was affected by DX. An impor tant increase in IRT levels was observed when CFPAC-1 cells and CAPAN- 1 cells were grown in the presence of DMSO, but for both cell lines th e cellular growth decreased in the presence of DMSO. Our data show tha t neither the IRT secretion level nor the differentiation state of the se cell lines correlates with cellular growth, and suggests that the e xpression of pancreatic proteases by these two tumor cell lines could be either related to a common stem cell with this potential or to a po ssible acinar origin of pancreatic cancer, as recently proposed by oth ers.