Expression of FK506 binding protein 65 (FKBP65) is decreased in epithelial ovarian cancer cells compared to benign tumor cells and to ovarian epithelium.

FK506 binding protein 65 (FKBP65) belongs to a group of proteins termed immunophilins that have a high binding affinity to immunosuppressant drugs as FK506 (tacrolimus) and rapamycin (sirolimus). Treatment of female premenopausal women with tacrolimus, which binds to FKBP65, has been reported to be followed by a strongly increased risk of ovarian cysts. We performed the present study to reveal how FKBP65 is expressed in the ovary and in ovarian tumors and to see if this expression might be related to ovarian tumor development, a relationship we have found in colorectal cancer. Biopsies from prospectively collected samples from ovaries and benign, borderline, and invasive ovarian tumors were analyzed for expression of FKBP65 by immunohistochemistry. The expression was compared to survival and several clinicopathological parameters. FKBP65 is strongly expressed in ovarian epithelium and in benign ovarian tumor cells. In the ovary, a positive staining was also found in endothelial cells of blood vessels. In non-invasive and in invasive malignant tumor cells, a decreased staining was observed, which was not correlated to stage, histology, or survival. A significant inversed correlation to expression of p53 was found. The differential expression of FKBP65 indicates a role in ovarian physiology as well as in ovarian tumor development. Our observations and the chromosomal localization of the FKBP65 gene indicate a tumor suppressor function of the FKBP65 protein in ovarian carcinogenesis.

Association between human papillomavirus 16 E6 variants and human leukocyte antigen class I polymorphism in cervical cancer of Swedish women.

Persistent infection with human papillomavirus (HPV), particularly HPV16, represents the prime risk factor in cervical carcinogenesis. HPV variants (e.g., within the E6 gene) together with immunogenetic factors of the host may be responsible either for effective viral clearance, or alternatively, for viral persistence. Peripheral blood from 27 HPV16 positive Swedish women with cervical carcinoma, who had previously been tested for HPV16 E6 variants, was used for human leukocyte antigen (HLA) class I typing. Women with HLA-B*44, HLA-B*51, or HLA-B*57 who were infected with the HPV16 E6 variant L83V had an approximately four- to fivefold increased risk for cancer compared with controls (odds ratio [OR] = 3.5, 95% CI = 1.1-11.1, OR = 4.2, 95% CI = 1.19-14.69, or OR = 4.67, 95% CI = 1.2-18.6, respectively). Epitope predictive algorithm with SYFPEITHI revealed that the variant at amino acid 83 affects the binding affinity in association with HLA-B*44. Interestingly, the HLA-B*15 allele seems protective because it was absent in HPV16 positive cancer. It is concluded that specific HLA class I alleles, combined with certain HPV16 E6 variants, may be crucial for immune surveillance in cervical carcinogenesis. The evaluation of associations of HLA alleles with HPV variants may be helpful in defining prognostic markers and in designing vaccines capable of mediating immune protection against HPV infection.

Expression of Bcl-2, Bcl-x, Mcl-1, Bax and Bak in human uterine leiomyomas and myometrium during the menstrual cycle and after menopause.

To investigate the expression of Bcl-2, Bcl-x, Mcl-1, Bax and Bak proteins in human uterine leiomyomas and homologous myometrium during the menstrual cycle and after menopause. The expression of Bcl-2, Bcl-x, Mcl-1, Bax and Bak in leiomyomas (n=24) and myometrial samples (n=22) from women with leiomyomas was measured by immunohistochemistry and Western blot. Measured by immunohistochemistry, a significant difference between leiomyomas and myometrium was observed only for the Bax protein, in tissues obtained from women in the secretory phase of the menstrual cycle. The Bcl-2 staining was more abundant in leiomyomas than in myometrium only in tissues obtained in the proliferative phase of the cycle. Bcl-2 was more abundant in leiomyomas from women of fertile age than in leiomyomas from menopausal women. No significant differences were observed for the Bcl-x or Bak proteins, whereas the Mcl-1 protein was significantly less abundant in secretory phase leiomyomas than in leiomyomas from menopausal women. Western blot analysis based on pools of tissue extracts from the different groups essentially confirmed the data obtained by immunohistochemistry. Bcl-2 family proteins are expressed in leiomyomas and myometrium in different phases related to and influenced by gonadal steroids. These proteins are suggested to interact with each other in the regulation of programmed cell death, apoptosis, but their specific role in growth control of uterine leiomyomas remains to be investigated.

Expression of serotonin receptors 5-HT1A, 5-HT1B, 5-HT2B and 5-HT4 in ovary and in ovarian tumours.

BACKGROUND: Recently we have shown that serotonin receptors may be involved in prostate cancer development. In ovarian carcinogenesis, oestrogen may play a role. As oestrogen seems to mediate at least some of its biological effects through serotonin, we decided to evaluate if serotonin receptors are expressed in ovary and in ovarian tumours and if the expression is correlated to ovarian tumour development. MATERIALS AND METHODS: An immunohistochemical study of the serotonin (5-HT) receptors 5-HTR1A, 5-HTR1B, 5-HTR2B and 5-HTR4 in frozen samples of ovary, and benign, borderline and invasive ovarian tumours was performed. RESULTS: Expression of all four serotonin receptors was strong to intermediate in the ovarian epithelium. In benign and non-invasive cancer cells, strong staining was seen, while in invasive cancer cells, decreased expression was observed. For 5-HTR2B, the decrease was correlated to dissemination of the disease. For none of the serotonin receptors was the expression correlated to survival. In the stromal part, a variable immunoreactivity was observed that was strongest for 5-HTR2B in both ovary and tumours. Staining of blood vessels was observed in ovary and all tumour groups for 5-HTR2B, but only occasionally was a weak expression seen for 5-HTR1A, 5-HTR1B and 5-HTR4. CONCLUSION: The staining pattern of serotonin receptors in ovary indicates their functional role in ovarian physiology. In ovarian tumours, the expression is in harmony with a tumour suppressor role in ovarian carcinogenesis, which is supported by observations in the literature. Further studies are necessary to resolve the connection between serotonin and ovarian tumour development.

The expression of ß-microseminoprotein but not CRISP3 is reduced in ovarian cancer and correlates to survival.

BACKGROUND: ß-Microseminoprotein (MSMB) is an abundant protein in seminal plasma. Most of it is present as a free protein but a small part is bound to cysteine-rich secretory protein 3 (CRISP3) as a non-covalent complex. Even though their physiological function is unknown, both MSMB and CRISP3 have been ascribed roles in prostate carcinogenesis. Thus, several recent experimental studies indicate a tumor-suppressor role for MSMB. The present study was undertaken in order to evaluate, for the first time, the expression of MSMB and CRISP3 in ovaries and in ovarian tumors and to determine if their expression might indicate a role in ovarian tumor development. MATERIALS AND METHODS: Biopsies from prospectively collected samples from ovaries and benign, borderline and invasive ovarian tumors were analyzed for expression of MSMB and CRISP3 by immunohistochemistry. In patients with ovarian cancer the expression was compared to survival. RESULTS: Both MSMB and CRISP3 were strongly stained in ovarian epithelial cells and weakly stained in the stroma. In ovarian blood vessels, CRISP3 exhibited strong to medium staining, while MSMB was only weakly expressed. In benign and borderline tumors the staining pattern was similar to the one observed in the ovaries. In invasive neoplasms, the expression of MSMB in the tumor cells was significantly reduced. In univariate analysis, decreased expression of MSMB correlated to reduced survival. No correlation was found with stage, the strongest prognostic indicator for ovarian cancer, which supports an independent role of MSMB in ovarian carcinogenesis. For CRISP3, a staining pattern comparable to that for MSMB was observed in all groups, except the fact that decreased expression was not observed in invasive tumor cells. CONCLUSION: MSMB and CRISP3 were widely distributed in ovaries and in ovarian tumors; the expression of MSMB fits well with a tumor-suppressor function in ovarian carcinogenesis.