Establishment and characterization of pthrp-producing human pancreatic-cancer cell-line

Human pancreatic ductal cell carcinoma cell line, which can secrete parathyroid hormone-related peptide (PTHrP), designated as KP 4, and its daughter cell lines with different PTHrP-secreting activities, termed KP 4-1 and KP 4-2, have been established in tissue culture. KP 4 cells were able to form tumors in nude mice. The absolute production rate of PTHrP in KP 4-1 was 5 to 10 times higher than that in KP 4-2. Similarly, the level of PTHrP mRNA in KP 4-1 was significantly higher than that in KP 4-2. KP 4-2 cells exhibited more rapid growth than KP 4 and KP 4-1 in vitro. Our established cell lines should provide a useful system to study the regulation of PTHrP production and its pathophysiological roles.