Effect of Human Seminal Fluid on Production of Messenger Ribonucleic Acid for Metalloproteinase 2 and Metalloproteinase 9 in Cervical Epithelial Carcinoma Cells

Objectives: The risk for cervical cancer is related to sexual intercourse. One factor associated with tumor invasion and metastases is the production of matrix metalloproteinases, which degrade the extracellular matrix. The ability of human semen to influence production of messenger ribonucleic acid for 2 matrix metalloproteinases associated with cervical cancer, MMP-2 and MMP-9, was examined.

Study Design: Seminal fluids from 16 men were diluted 1:50 and incubated with the cervical carcinoma cell line HeLa for 18 hours. Cells were harvested, ribonucleic acid was isolated and reverse transcribed into complementary deoxyribonucleic acid, and deoxyribonucleic acid sequences coding for regions of the genes for MMP-2 and MMP-9 were generated by polymerase chain reaction and detected by enzyme-linked immunosorbent assay.

Results: All 16 semen samples inhibited production of MMP-2 messenger ribonucleic acid. The MMP-2 messenger ribonucleic acid synthesis in the presence of semen was a mean of 39.5% of the control value. In contrast, MMP-9 messenger ribonucleic acid synthesis was stimulated (mean stimulation, 68.3%) by semen in 10 of the 15 samples tested. Synthesis of beta-actin was comparable in each culture, and cell viability was unaffected by the diluted semen.

Conclusion: The capacity of semen to influence transcription of the genes for matrix metalloproteinases may be one mechanism whereby sexual activity influences cervical cancer progression.