Genetic variation in progesterone receptor gene and ovarian cancer risk: A case control study

Low androgen/progesterone or high oestrogen/androgen receptors ratio in serous ovarian cancer predicts longer survival

The treatment of ovarian cancer (OC) remains one of the greatest challenges in gynaecological oncology. The presence of classic steroid receptors in OC makes hormone therapy an attractive option; however, the response of OC to hormone therapy is modest. Here, we compared the expression patterns of progesterone (PGR), androgen (AR) and oestrogen alpha (ERα) receptors between serous OC cell lines and non-cancer ovarian cells. These data were analysed in relation to steroid receptor expression profiles from patient tumour samples and survival outcomes using a bioinformatics approach. The results showed that ERα, PGR and AR were co-expressed in OC cell lines, and patient samples from high-grade and low-grade OC co-expressed at least two steroid receptors. High AR expression was negatively correlated, whereas ERα and PGR expression was positively correlated with patient survival. AR showed the opposite expression pattern to that of ERα and PGR in type 1 (SKOV-3) and 2 (OVCAR-3) OC cell lines compared with non-cancer (HOSEpiC) ovarian cells, with AR downregulated in type 1 and upregulated in type 2 OC. A low AR/PGR ratio and a high ESR1/AR ratio were associated with favourable survival outcomes in OC compared with other receptor ratios. Although the results must be interpreted with caution because of the small number of primary tumour samples analysed, they nevertheless suggest that the evaluation of ERα, AR and PGR by immunohistochemistry should be performed in patient biological material to plan future clinical trials.

Blood Plasma Small Non-Coding RNAs as Diagnostic Molecules for the Progesterone-Receptor-Negative Phenotype of Serous Ovarian Tumors

The expression level of the progesterone receptor (PGR) plays a crucial role in determining the biological characteristics of serous ovarian carcinoma. Low PGR expression is associated with chemoresistance and a poorer outcome. In this study, our objective was to explore the relationship between tumor progesterone receptor levels and RNA profiles (miRNAs, piwiRNAs, and mRNAs) to understand their biological characteristics and behavior. To achieve this, we employed next-generation sequencing of small non-coding RNAs, quantitative RT-PCR, and immunohistochemistry to analyze both FFPE and frozen tumor samples, as well as blood plasma from patients with benign cystadenoma (BSC), serous borderline tumor (SBT), low-grade serous ovarian carcinoma (LGSOC), and high-grade serous ovarian carcinoma (HGSOC). Our findings revealed significant upregulation of MMP7 and MUC16, along with downregulation of PGR, in LGSOC and HGSOC compared to BSC. We observed significant correlations of PGR expression levels in tumor tissue with the contents of miR-199a-5p, miR-214-3p, miR-424-3p, miR-424-5p, and miR-125b-5p, which potentially target MUC16, MMP7, and MMP9, as well as with the tissue content of miR-16-5p, miR-17-5p, miR-20a-5p, and miR-93-5p, which are associated with the epithelial-mesenchymal transition (EMT) of cells. The levels of EMT-associated miRNAs were significantly correlated with the content of hsa_piR_022437, hsa_piR_009295, hsa_piR_020813, hsa_piR_004307, and hsa_piR_019914 in tumor tissues. We developed two optimal logistic regression models using the quantitation of hsa_piR_020813, miR-16-5p, and hsa_piR_022437 or hsa_piR_004307, hsa_piR_019914, and miR-93-5p in the tumor tissue, which exhibited a significant ability to diagnose the PGR-negative tumor phenotype with 93% sensitivity. Of particular interest, the blood plasma levels of miR-16-5p and hsa_piR_022437 could be used to diagnose the PGR-negative tumor phenotype with 86% sensitivity even before surgery and chemotherapy. This knowledge can help in choosing the most effective treatment strategy for this aggressive type of ovarian cancer, such as neoadjuvant chemotherapy followed by cytoreduction in combination with hyperthermic intraperitoneal chemotherapy and targeted therapy, thus enhancing the treatment's effectiveness and the patient's longevity.

Decreased risk of ovarian cancer associated with rs9898876 sex hormone-binding globulin gene variant

BACKGROUND

Ovarian cancer (OC) is one of the most common gynecologic cancers,with significant morbidity and mortality. The risk of OC is influenced by hormone status, of which sex hormone-binding globulin (SHBG), which influences the serum availability of steroid sex hormones, is implicated in the pathogenesis and evolution of OC. The aim of this study is to evaluate the involvement of common SHBG gene variants in OC susceptibility and evolution.

MATERIALS

A case control study including 71 OC patients and 74 cancer-free controls, who were genotyped for rs9898876, rs13894, rs1799941 and rs6257 SHBG SNP. Genotyping was done by the allelic discrimination method, using VIC- and FAM-labeled primers.

RESULTS

The minor allele frequencies of rs9898876, rs13894, rs1799941 and rs6257 SHBG SNP was comparable between OC cases and control women, implying no significant associations of the tested variants and overall OC risk. Taking homozygous wild-type genotype as reference (OR = 1.00), heterozygous rs9898876 (G/T), and minor allele-carrying genotypes [G/T + T/T] were associated with reduced risk of OC. While rs9898876 heterozygosity (G/T) was predictive of OC occurrence, no significant association of the remaining three tested SNPs was noted with altered risk of OC. Irrespective of FIGO staging, the four tested SHBG SNPs were not associated with the clinical progression of OC.

CONCLUSIONS

In conclusion, SHBG rs9898876 is associated with a decreased risk of OC, and thus constitutes a potential diagnostic biomarker of OC.