Ovarian cancer (OC) is highly lethal and heterogeneous. Several hormones are involved in OC etiology including estrogens; however, their role in OC is not completely understood. Here, we performed targeted transcriptomics and estrogen metabolism analyses in high-grade serous OC (HGSOC), OVSAHO, Kuramochi, COV632, and immortalized normal ovarian epithelial HIO-80 cells. We compared these data with public transcriptome and proteome data for the HGSOC tissues. In all model systems, high steroid sulfatase expression and weak/undetected aromatase (CYP19A1) expression indicated the formation of estrogens from the precursor estrone-sulfate (E1-S). In OC cells, the metabolism of E1-S to estradiol was the highest in OVSAHO, followed by Kuramochi and COV362 cells, and decreased with increasing chemoresistance. In addition, higher HSD17B14 and CYP1A2 expressions were observed in highly chemoresistant COV362 cells and platinum-resistant tissues compared to those in HIO-80 cells and platinum-sensitive tissues. The HGSOC cell models differed in HSD17B10, CYP1B1, and NQO1 expression. Proteomic data also showed different levels of HSD17B10, CYP1B1, NQO1, and SULT1E1 between the four HGSOC subtypes. These results suggest that different HGSOC subtypes form different levels of estrogens and their metabolites and that the estrogen-biosynthesis-associated targets should be further studied for the development of personalized treatment.

Endometrial cancer (EC) is associated with increased estrogen actions. Locally, estrogens can be formed from estrone-sulphate (E1-S) after cellular uptake by organic anion-transporting polypeptides (OATP) or organic anion transporters (OAT). Efflux of E1-S is enabled by ATP Binding Cassette transporters (ABC) and organic solute transporter (OST)αβ. Currently, 19 E1-S transporters are known but their roles in EC are not yet understood. Here, we analysed levels of E1-S transporters in Ishikawa (premenopausal EC), HEC-1-A (postmenopausal EC), HIEEC (control) cell lines, in EC tissue, examined metabolism of steroid precursor E1-S, studied effects of OATPs’ inhibition and gene-silencing on E1-S uptake, and assessed associations between transporters and histopathological data. Results revealed enhanced E1-S metabolism in HEC-1-A versus Ishikawa which could be explained by higher levels of OATPs in HEC-1-A versus Ishikawa, especially 6.3-fold up-regulation of OATP1B3 (SLCO1B3), as also confirmed by immunocytochemical staining and gene silencing studies, lower ABCG2 expression and higher levels of sulfatase (STS). In EC versus adjacent control tissue the highest differences were seen for ABCG2 and SLC51B (OSTβ) which were 3.0-fold and 2.1-fold down-regulated, respectively. Immunohistochemistry confirmed lower levels of these two transporters in EC versus adjacent control tissue. Further analysis of histopathological data indicated that SLCO1B3 might be important for uptake of E1-S in tumours without lymphovascular invasion where it was 15.6-fold up-regulated as compared to adjacent control tissue. Our results clearly indicate the importance of E1-S transporters in EC pathophysiology and provide a base for further studies towards development of targeted treatment.

High-grade serous ovarian cancer (HGSOC) is currently treated with cytoreductive surgery and platinum-based chemotherapy. The majority of patients show a primary response; however, many rapidly develop drug resistance. Antiestrogens have been studied as low toxic treatment options for HGSOC, with higher response rates in platinum-sensitive cases. Mechanisms for this difference in response remain unknown. Therefore, the present study investigated the impact of platinum resistance on steroid metabolism in six established HGSOC cell lines sensitive and resistant against carboplatin using a high-resolution mass spectrometry assay to simultaneously quantify the ten main steroids of the estrogenic metabolic pathway. An up to 60-fold higher formation of steroid hormones and their sulfated or glucuronidated metabolites was observed in carboplatin-sensitive cells, which was reversible by treatment with interleukin-6 (IL-6). Conversely, treatment of carboplatin-resistant cells expressing high levels of endogenous IL-6 with the monoclonal anti-IL-6R antibody tocilizumab changed their status to “platinum-sensitive”, exhibiting a decreased IC₅₀ value for carboplatin, decreased growth, and significantly higher estrogen metabolism. Analysis of these metabolic differences could help to detect platinum resistance in HGSOC patients earlier, thereby allowing more efficient interventions.

Endometrial cancer (EC) is the most common gynecological malignancy in the Western world. The molecular basis and effects of various agents are frequently studied in model EC cell lines, but the most commonly used cell lines Ishikawa, HEC1-A, RL95-2 and KLE have not been thoroughly and systematically investigated. We characterized EC cell lines of different grades by reassessing the expression of estrogen receptors ERα, ERβ, and GPER by qPCR and Western blot and investigated the effects of estrogens, estrone-sulfate, estrone and estradiol on their proliferation, migration, and clonogenicity. Estradiol promoted the proliferation of grade 1 Ishikawa EC cells and grade 2 RL95-2 cells. Estrone and estrone sulfate also stimulated the proliferation of Ishikawa, showed a tendency to increase the proliferation of HEC-1-A and RL95-2 cells, but decreased the proliferation of KLE. Estrogens had no effect on the migration and clonogenicity of these four EC cell lines, however, there was a trend toward a smaller colony area for cells incubated with higher estrogen concentrations. We have previously shown that in EC estradiol forms from inactive estrone sulfate via the sulfatase pathway. This study showed that estrogens significantly promote the proliferation of grade 1 Ishikawa EC cells, and grade 2 RL95-2 and decrease the proliferation of grade 3 KLE cells. These differences in proliferation were associated with ERα positivity of Ishikawa cells and GPER expression in other cells.

Endometrial cancer (EC) is an increasing health concern, with its growth driven by an angiogenic switch that occurs early in cancer development. Our study used publicly available datasets to examine the expression of angiogenesis-related genes and proteins in EC tissues, and compared them with adjacent control tissues. We identified nine genes with significant differential expression and selected six additional antiangiogenic genes from prior research for validation on EC tissue in a cohort of 36 EC patients. Using machine learning, we built a prognostic model for EC, combining our data with The Cancer Genome Atlas (TCGA). Our results revealed a significant up-regulation of IL8 and LEP and down-regulation of eleven other genes in EC tissues. These genes showed differential expression in the early stages and lower grades of EC, and in patients without deep myometrial or lymphovascular invasion. Gene co-expressions were stronger in EC tissues, particularly those with lymphovascular invasion. We also found more extensive angiogenesis-related gene involvement in postmenopausal women. In conclusion, our findings suggest that angiogenesis in EC is predominantly driven by decreased antiangiogenic factor expression, particularly in EC with less favourable prognostic features. Our machine learning model effectively stratified EC based on gene expression, distinguishing between low and high-grade cases.