Messenger ribonucleic acid expression of LH/hCG receptor gene in human ovarian carcinomas

The mRNA expression of luteinizing hormone (LH)/human chorionic gonadotropin (hCG) receptors was analysed by the RT-nested PCR method in five normal ovarian tissues, 62 ovarian tumours (5 benign, 7 borderline and 43 malignant epithelial tumours, 3 sex cord-stromal tumours and 4 germ cell tumours) and in 2 ovarian cancer cell lines. In normal ovaries, two cDNA fragments of different sizes were detected using primers designed to amplify a region including exon 9. Sequencing revealed that the larger fragment was derived from a full-length receptor, while the smaller fragment was a splice variant lacking exon 9. In ovarian tumours, the larger fragment of LH/hCG receptors was detected in 40% of the epithelial ovarian carcinomas, none of the germ cell tumours, all of the sex cord-stromal tumours and one of the 2 ovarian cancer cell lines. Immunohistochemistry confirmed the localisation of LH/hCG receptor protein in the tumour cells which correlated with mRNA expression. Patients with full-length LH/hCG receptors in carcinomas showed a better prognosis compared with those without the receptors.