Expression of CD40 and growth-inhibitory activity of CD40 ligand in ovarian cancer cell lines.
OBJECTIVE
Soluble recombinant human CD40 ligand trimer (rhuCD40Lt) has shown antitumor activity in preclinical and clinical studies. We evaluated the effect of rhuCD40Lt on epithelial ovarian carcinoma (EOC) cell lines.


METHODS
Expression of the receptor, CD40, was determined by reverse transcriptase-polymerase chain reaction and flow cytometry, and antiproliferative effects of rhuCD40Lt, either alone or in combination with recombinant interferon-gamma (rIFN-gamma), were examined in 8 EOC lines.


RESULTS
Expression of CD40 was elevated in 5 out of 8 EOC cell lines examined by flow cytometry, and the presence of CD40 transcripts was detected by RT-PCR in all 8 cell lines. CD40 expression was increased by rIFN-gamma, but treatment with rhuCD40Lt decreased CD40 expression in 4 of the 5 lines that had shown elevated CD40 expression. rhuCD40Lt had a growth-inhibitory effect on 2774 cells, which also exhibited the highest level of CD40 expression. Growth-inhibitory effect of rhuCD40Lt was additive with rIFN-gamma on 2774, NMP-1, a cisplatin-resistant subline of OVCAR3, and HEY cell lines. The number of apoptotic tumor cells was increased following treatment with rhuCD40Lt.


CONCLUSIONS
CD40 is expressed on EOC cell lines, and expression was found at the transcript level in all of the EOC lines examined. rIFN-gamma enhances CD40 expression, though a decrease in CD40 expression was observed following treatment with rhuCD40Lt. Growth-inhibitory activity of rhuCD40Lt on EOC lines that express CD40 could be enhanced when rhuCD40Lt treatment was combined with rIFN-gamma. These results suggest that future studies of the combination of rhuCD40Lt and rIFN-gamma might warrant consideration.
Melichar
Bohuslav
B
Department of Oncology and Radiotherapy and Medicine, Charles University Medical School, Hradec Kralove, Czech Republic.
Patenia
Rebecca
R
Gallardo
Stacie
S
Melicharová
Karolina
K
Hu
Wei
W
Freedman
Ralph S
RS
D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology; D019013:CD40 Antigens / Q000096:biosynthesis*; D023201:CD40 Ligand / Q000008:administration & dosage / Q000494:pharmacology*; D048708:Cell Growth Processes / Q000187:drug effects; D045744:Cell Line, Tumor; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D007371:Interferon-gamma / Q000008:administration & dosage; D010051:Ovarian Neoplasms / Q000188:drug therapy / Q000276:immunology / Q000473:pathology; D011994:Recombinant Proteins / Q000494:pharmacology; D020133:Reverse Transcriptase Polymerase Chain Reaction
D019013:CD40 Antigens; D011994:Recombinant Proteins; D023201:CD40 Ligand; D007371:Interferon-gamma