Sensitivity Of Endometrial Cancer Cells Research Articles

MG132-mediated Suppression of the Ubiquitin-proteasome Pathway Enhances the Sensitivity of Endometrial Cancer Cells to Cisplatin.

Tumor cell resistance to cisplatin is a common challenge in endometrial cancer chemotherapy, stemming from various mechanisms. Targeted therapies using proteasome inhibitors, such as MG132, have been investigated to enhance cisplatin sensitivity, potentially offering a novel treatment approach. The aim of this study was to investigate the effects of MG132 on cisplatin sensitivity in the human endometrial cancer (EC) cell line RL95-2, focusing on cell proliferation, apoptosis, and cell signaling. Human endometrial cancer RL95-2 cells were exposed to MG132, and cell viability was assessed in a dose-dependent manner. The study evaluated the effect of MG132 on cisplatin-induced proliferation inhibition and apoptosis, correlating with caspase-3 activation and reactive oxygen species (ROS) upregulation. Additionally, we examined the inhibition of the ubiquitin-proteasome system and the expression of pro-inflammatory cytokines IL-1β, IL-6, IL-8, and IL-13 during MG132 and cisplatin co-administration. MG132 exposure significantly reduced cell viability in a dose-dependent manner. It augmented cisplatin- induced proliferation inhibition and enhanced apoptosis, correlating with caspase-3 activation and ROS upregulation. Molecular analysis revealed a profound inhibition of the ubiquitin-proteasome system. MG132 also significantly increased the expression of cisplatin-induced pro-inflammatory cytokines, suggesting a transition from chronic to acute inflammation. MG132 enhances the therapeutic efficacy of cisplatin in human EC cells by suppressing the ubiquitin- proteasome pathway, reducing cell viability, enhancing apoptosis, and shifting the inflammatory response. These findings highlighted the potential of MG132 as an adjuvant in endometrial cancer chemotherapy. Further research is needed to explore detailed mechanisms and clinical applications of this combination therapy.

Fanconi anemia complementation group D2 promotes sensitivity of endometrial cancer cells to chemotherapeutic agents by inhibiting the ferroptosis pathway

BackgroundResistance can develop during treatment of advanced endometrial cancer (EC), leading to unsatisfactory results. Fanconi anemia complementation group D2 (Fancd2) has been shown to be closely related to drug resistance in cancer cells. Therefore, this study was designed to explore the correlation of Fancd2 with EC resistance and the mechanism of Fancd2.MethodsReal-time quantitative PCR (RT-qPCR) was used to detect the expression of Fancd2 in EC tissues and cells. EC cells (Ishikawa) and paclitaxel-resistant EC cells (Ishikawa/TAX) were transfected to knock down Fancd2. In addition, the ferroptosis inhibitor Ferrostatin-1 was adopted to treat Ishikawa/TAX cells. The sensitivity of cancer cells to chemotherapeutic agents was observed via 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, and inhibitory concentration (IC)50 was calculated. Reactive oxygen species (ROS) levels were measured by flow cytometry, the activity of malondialdehyde (MDA) and the levels of glutathione (GSH) and Fe2+ in cells were detected by corresponding kits, and protein expression of solute farrier family 7 member 11 (SLC7A11) and glutathione peroxidase 4 (GPX4) was obtained through western blot.ResultsCompared with the normal tissues and endometrial epithelial cells, Fancd2 expression was significantly increased in EC tissues and Ishikawa cells, respectively. After knock-down of Fancd2, Ishikawa cells showed significantly increased sensitivity to chemotherapeutic agents. Besides, compared with Ishikawa cells, the levels of ROS, the activity of MDA, and the levels of GSH and Fe2+ were significantly decreased in Ishikawa/TAX cells, while the expression levels of SLC7A11 and GPX4 were significantly increased. Knock-down of Fancd2 significantly increased the ferroptosis levels in Ishikawa/TAX cells, but this effect could be reversed by Ferrostatin-1.ConclusionFancd2 increases drug resistance in EC cells by inhibiting the cellular ferroptosis pathway.

KLF9‑regulated FBXO31 inhibits the progression of endometrial cancer and enhances the sensitivity of endometrial cancer cells to cisplatin.

Endometrial cancer (EC) is one of the most common malignancies with an increasing annual incidence. F-box only protein 31 (FBXO31) plays a significant regulatory role in several types of cancer. The transcription factor Krüppel-like factor 9 (KLF9) of FBXO31 is reduced in EC as a tumor suppressor. However, their particular regulatory role and mechanism in EC have not been previously reported. Therefore, the UALCAN database was used to predict the expression levels of FBXO31 in EC. In addition, the regulatory effect of FBXO31 on EC cell proliferation, invasion, migration, apoptosis and cisplatin (DDP) sensitivity was investigated at the cellular level. The association between KLF9 and FBXO31 was predicted using the JASPAR database and verified by chromatin immunoprecipitation and luciferase reporter assays. Finally, the regulatory effects of KLF9 and FBXO31 overexpression or silencing were also explored. The results demonstrated that FBXO31 was poorly expressed in EC. Additionally, FBXO31 overexpression inhibited the malignant progression of EC cells and enhanced their sensitivity to DDP. Furthermore, KLF9 promoted FBXO31 transcription. Overall, the present study suggested that the KLF9-mediated regulation of FBXO31 could inhibit the progression of EC and enhance the sensitivity of EC cells to DDP.

Inhibition of ATM with KU-55933 Sensitizes Endometrial Cancer Cell Lines to Olaparib.

Endometrial cancer (EC) is one of the most prevalent gynecologic cancers, which poses a serious threat to women's health worldwide. Olaparib, the first FDA-approved PARP inhibitor for the treatment of BRCA-mutated breast, ovarian and pancreatic cancers, triggers apoptosis of cancer cells through synthetic lethality by inhibiting PARP1/2 enzymatic activity and BRCA1/2-dependent homologous recombination (HR) repair deficiency. However, the synergistic lethal effects between Olaparib and inhibitors of other DNA damage response proteins, such as ATM, PTEN and RAD51, are still unknown. Exploring the synergistic lethal effect between Olaparib and KU-55933 on EC. The GEPIA database was used to test EC patient survival rate. CCK8 was used for cell viability assays. Western blot was used for examining gene levels. The wound healing assay was used to detect cell migration ability. Flow cytometry was used for detecting the apoptosis rate. All experimental conditions were repeated independently in triplicate and analyzed in three separate experiments. In this study, we discovered that the frequency of ATM alterations in endometrial cancer reaches nearly 20% and that there is a positive correlation between ATM alterations and prognosis. Furthermore, we discovered that endometrial cells with low expression levels of ATM are sensitive to Olaparib. Treatment with KU-55933, a specific inhibitor of ATM, significantly enhanced the sensitivity of endometrial cancer cells to Olaparib, as evidenced by colony formation, cell migration and apoptosis assay. Further analysis revealed that KU-55933 potentiates Olaparib-induced cell apoptosis by inhibiting ATM phosphorylation. Our study demonstrates that inhibiting ATM could enhance the sensitivity of endometrial cancer to Olaparib, thereby providing a potential alternative treatment for the clinical treatment of endometrial cancer.

NrCAM secreted by endometrial stromal cells enhances the progestin sensitivity of endometrial cancer cells through epigenetic modulation of PRB

Progestin is one of the main hormone treatment regimens for early-stage estrogen receptor- and progesterone receptor (PR)-positive endometrial cancer (EC). However, the response rate of EC to progestins is unsatisfactory. Investigating the mechanisms related to progestin treatment could help improve treatment efficacy. Studies have demonstrated that normal endometrial stromal cells (ESCs) increase the inhibitory effect of progestin on EC cell proliferation via paracrine signaling, but the mechanisms involved remain unclear. In this study, we found that ESCs had different morphological features between progestin-sensitive and -insensitive EC tissues. ESCs presented typical decidualization changes in progestin-sensitive cases, while they remained slim in progestin-insensitive EC lesions, indicating no response. Furthermore, ESCs enhanced the inhibitory effect of medroxyprogesterone acetate (MPA) on EC cell proliferation by secreting neuron cell adhesion molecule (NrCAM). MPA treatment enhanced NrCAM secretion by ESCs. EC xenografts in BALB/C nude mice demonstrated that MPA combined with NrCAM had an increased tumor inhibitory effect compared with MPA or NrCAM alone. Mechanistically, MPA upregulated NrCAM expression in ESCs through PR. Specifically, NrCAM increased PR expression in EC cells through TET1-induced hydroxymethylation of the PRB gene promoter region. These findings indicate that NrCAM or NrCAM combined with progestins could be a new EC treatment.

Stigmasterol sensitizes endometrial cancer cells to chemotherapy by repressing Nrf2 signal pathway

BackgroundChemoresistance reduces the 5-year survival rate of endometrial cancer patient, which is the current major obstacle for cancer therapy. Increasing evidence state that Nrf2 contributes to chemoresistance in several kinds of cancer. However, its role in endometrial cancer cells remains unclarified.MethodsImmunohistochemistry staining was used to detect the expression of Nrf2 in normal patient and endometrial cancer patient. Stable transfection Ishikawa cell line with high level of Nrf2 was established to evaluate its role in chemoresistance. Dot blot assays were used to assess global hydroxymethylation level after stigmasterol treatment. Cellular growth profile was detected by CCK8 assay. Western blot was used to evaluate the changes of the target molecules after various treatments.ResultsNrf2 is overexpressed in endometrial cancer tissues compared with the normal endometrium. Overexpression of Nrf2 resulted in decrease sensitivity to cisplatin. In addition, stigmasterol has been identified as a novel Nrf2 inhibitor. It enhanced the sensitivity of endometrial cancer cells to cisplatin, and the underlying mechanism is that stigmasterol declines the Nrf2 protein level.ConclusionsOur findings identified stigmasterol as a new potential inhibitor of Nrf2 and highlight a critical role of stigmasterol in overcoming chemoresistance in endometrial cancer therapy.

Methylsulfonylmethane sensitizes endometrial cancer cells to doxorubicin

BackgroundMethylsulfonylmethane (MSM) is a commonly used diet supplement believed to decrease the inflammation in joints and fastens recovery in osteoarthritis, gastric mucosal injury, or obesity-related disorders. It was also suggested that MSM might play a beneficial role in cancer treatment.PurposeSo far, the MSM might have a potentially beneficial effect in endometrial cancer (EC) treatment.Study designThis study evaluated the effect and usefulness of MSM in combinatory therapy with known drug doxorubicin (DOX).MethodsThe effect of combinational treatment of MSM and DOX on the induction of apoptosis was evaluated in EC cell lines (ISHIKAWA, MFE-296, MFE-280).ResultsWe observed that MSM itself induces apoptosis in EC cell lines, and pre-treatment with MSM for 24 h increases the sensitivity of EC cells to DOX-induced apoptosis and DNA damage and that effect might be regulated by p42/44 (Erk1/2) MAPK and Akt (protein kinase B).ConclusionThese results for the first time show that MSM might act as a sensitizer of EC cells to known drugs, for which EC cells quickly acquire resistance.Graphical abstract

Effect of microRNA-29b on proliferation, migration, and invasion of endometrial cancer cells.

ObjectiveAberrant expression of microRNAs is a key regulator of tumorigenesis and progression in endometrial cancer. We assessed the effect of microRNA-29b (miR-29b) on proliferation, chemosensitivity, migration, and invasion of endometrial cancer cells.MethodsThe proliferation of endometrial cancer cells was examined by water-soluble tetrazolium (WST)-1 assay. The effects of miR-29b on migration and invasion were evaluated by transwell migration and Matrigel invasion assays. Western blotting was used to assess protein expression levels after altered expression of miR-29b. The effect of miR-29b on cisplatin-induced apoptosis was examined by Caspase-Glo 3/7 assay.ResultsmiR-29b inhibited proliferation and decreased migration and invasion of endometrial cancer cells. It also enhanced the sensitivity of endometrial cancer cells to cisplatin and increased cisplatin-induced apoptosis by regulating expression of BAX and Bcl-2. Moreover, miR-29b changed the expression level of phosphatase and tensin homolog (PTEN) and p-AKT by directly binding to the 3′ untranslated region of PTEN.ConclusionmiR-29b played important roles in proliferation and progression in endometrial cancer cells by direct regulation of PTEN. It might be used as a biomarker to predict chemotherapy response and prognosis in endometrial cancer.

An optical study of drug resistance detection in endometrial cancer cells by dynamic and quantitative phase imaging.

Platinum chemosensitivity detection plays a vital role during endometrial cancer treatment because chemotherapy responses have profound influences on patient's prognosis. Although several methods can be used to detect drug resistance characteristics, studies on detecting drug sensitivity based on dynamic and quantitative phase imaging of cancer cells are rare. In this study, digital holographic microscopy was applied to distinguish drug‐resistant and nondrug‐resistant endometrial cancer cells. Based on the reconstructed phase images, temporal evolutions of cell height (CH), cell projected area (CPA) and cell volume were quantitatively measured. The results show that change rates of CH and CPA were significantly different between drug‐resistant and nondrug‐resistant endometrial cancer cells. Furthermore, the results demonstrate that morphological characteristics have the potential to be utilized to distinguish the drug sensitivity of endometrial cancer cells, and it may provide new perspectives to establish optical methods to detect drug sensitivity and guide chemotherapy in endometrial cancer.

MicroRNA-423 promotes proliferation, migration and invasion and induces chemoresistance of endometrial cancer cells.

Altered microRNA expression serves essential roles in tumorigenesis and progression in endometrial cancer. In the present study the effect of miR-423 on proliferation, chemosensitivity, migration and invasion of endometrial cancer cells was examined. A WST-1 assay was used to examine the proliferation of HEC-1B and Ishikawa endometrial cancer cells with either upregulation or downregulation of miR-423, with or without cisplatin treatment. The migration and invasion of HEC-1B and Ishikawa endometrial cancer cells were examined via Transwell migration and Matrigel invasion assays. Protein expression levels, including B cell lymphoma-2 (Bcl-2), Bcl-2 associated X protein, E- and N-cadherin, snail, vimentin, phosphatase and tensin homolog (PTEN) and protein kinase B (AKT) were examined by western blotting. A caspase-Glo3/7 assay was carried out to evaluate the effect of miR-423 on cisplatin-induced apoptosis in HEC-1B and Ishikawa endometrial cancer cells. Overexpression of miR-423 enhanced the proliferation, and increased migration and invasion in endometrial cancer cells. miR-423 also decreased the sensitivity of endometrial cancer cells following cisplatin treatment. miR-423 inhibited cisplatin-induced apoptosis in endometrial cancer cells by regulation of caspase 3/7 and Bcl-2 expression. Furthermore, the E-cadherin expression was significantly decreased, and the expression of N-cadherin, snail and Vimentin were increased in both HEC-1B cells and Ishikawa cells following overexpression of miR-423. Conversely, downregulation of miR-423 increased the expression of E-cadherin and decreased the expression of N-cadherin, snail and Vimentin. Further experiments demonstrated that the expression levels of PTEN and phosphorylated-AKT in HEC-1B and Ishikawa endometrial cancer cells was decreased and increased, respectively, following aberrant expression of miR-423. miR-423 displayed an important role in tumorigenesis and progression in endometrial cancer cells, and may therefore be used as a potential biomarker to predict chemotherapy response and prognosis in endometrial cancer.

Gefitinib enhances sensitivity of endometrial cancer cells to progestin therapy via dual-specificity phosphatase 1.

In this study, we investigated if Gefitinib, an epidermal growth factor receptor (EGFR) inhibitor, augments endometrial cancer (EC) therapy with medroxyprogesterone acetate (MPA). Combined treatment with Gefitinib plus MPA decreased the proliferation and invasiveness of the Ishikawa and RL952 EC cell lines more effectively than MPA treatment alone. Moreover, combined treatment with Gefitinib plus MPA reduced growth of EC xenografts in Balb/c nude mice more than either Gefitinib or MPA alone. The therapeutic efficacy of combined Gefitinib plus MPA treatment was dependent on expression of dual-specificity phosphatase 1 (DUSP1). DUSP1 knockdown in Ishikawa cells treated with Gefitinib plus MPA showed greater proliferation and invasiveness than parental Ishikawa cells treated similarly. EC cells treated with the combination of Gefitinib plus MPA also showed DUSP1-dependent reductions in phospho-ERK1/2 and increases in E-Cadherin. Thus, Gefitinib appears to DUSP1-dependently enhance the therapeutic efficacy of progestin in EC cells.

Additional effects of engineered stem cells expressing a therapeutic gene and interferon-β in a xenograft mouse model of endometrial cancer.

Endometrial cancer is the most common gynecologic malignancy in women worldwide. In the present study, we evaluated the effects of neural stem cell-directed enzyme/prodrug therapy (NDEPT) designed to more selectively target endometrial cancer. For this, we employed two different types of neural stem cells (NSCs), HB1.F3.CD and HB1.F3.CD.IFN-β cells. Cytosine deaminase (CD) can convert the non-toxic prodrug, 5-fluorocytosine (5-FC), into a toxic agent, 5-fluorouracil (5-FU), which inhibits DNA synthesis. IFN-β is a powerful cytotoxic cytokine that is released by activated immune cells or lymphocytes. In an animal model xenografted with endometrial Ishikawa cancer cells, the stem cells stained with CM-DiI were injected into nearby tumor masses and 5-FC was delivered by intraperitoneal injection. Co-expression of CD and IFN-β significantly inhibited the growth of cancer (~50-60%) in the presence of 5-FC. Among migration-induced factors, VEGF gene was highly expressed in endometrial cancer cells. Histological analysis showed that the aggressive nature of cancer was inhibited by 5-FC in the mice treated with the therapeutic stem cells. Furthermore, PCNA expression was more decreased in HB1.F3.CD.IFN-β treated mice rather than HB1.F3.CD treated mice. To confirm the in vitro combined effects of 5-FU and IFN-β, 5-FU was treated in Ishikawa cells. 5-FU increased the IFN-β/receptor 2 (IFNAR2) and BXA levels, indicating that 5-FU increased sensitivity of endometrial cancer cells to IFN-β, leading to apoptosis of cancer cells. Taken together, these results provide evidence for the efficacy of therapeutic stem cell-based immune therapy involving the targeted expression of CD and IFN-β genes at endometrial cancer sites.

Sensitivity of endometrial cancer cells from primary human tumor samples to new potential anticancer peptide lactaptin.

Endometrial carcinoma is the most common gynecologic malignancy which is associated with a poor prognosis when diagnosed at an advanced stage; therefore, the discovery of efficacious new drugs is required to reinforce conventional chemotherapy. Short-term cultures of primary cells from endometrial tumors could be used for testing new anticancer therapeutics as well as for the development of personalized cancer therapy strategy. Here, the antitumor effect of a recombinant analogue of lactaptin (RL2), a new potential anticancer molecule, was examined against primary human endometrial cancer cells. Primary cell cultures of malignant and normal human endometrium were performed by enzymatic digestion of endometrial tissue from biopsy material. Real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) was performed to determine the messenger ribonucleic acid (mRNA) state of estrogen (ERs) and progesterone (PRs) hormone receptors and aromatase (Cyp 19) in cell cultures. Dynamic monitoring of cell adhesion and proliferation was made using the iCELLigence system (ASEA Biosciences). The sensitivity of cell cultures to conventional anticancer drugs and the lactaptin analog was estimated by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, flow cytometry, and the iCELLligence system. Established short-term primary cultures of endometrial cancer cells were ERα/ERβ/PR-positive and sensitive for RL2. The IC 50 values of doxorubicin and cisplatin were determined for all of the primary cultures designed. KE normal cells displaying low Cyp19 mRNA levels and high ERβ and PR mRNA levels were more resistant to RL2 treatment as well as to cisplatin and doxorubicin. Our results indicate that the recombinant analog of lactaptin, RL2, exerts cytotoxic effects against primary hormone-dependent endometrial tumor cells in vitro with features of apoptosis.

SALL4 is a new target in endometrial cancer

Aggressive cancers and embryonic stem (ES) cells share a common gene expression signature. Identifying the key factors/pathway(s) within this ES signature responsible for the aggressiveness of cancers can lead to a potential cure. In this study, we find that SALL4, a gene involved in the maintenance of ES cell self-renewal, is aberrantly expressed in 47.7% of primary human endometrial cancer samples. It is not expressed in normal or hyperplastic endometrial. More importantly, SALL4 expression is positively correlated with worse patient survival and aggressive features such as metastasis in endometrial carcinoma. Further functional studies have shown that loss of SALL4 inhibits endometrial cancer cell growth in vitro and tumorigenicity in vivo, as a result of inhibition of cell proliferation and increased apoptosis. In addition, down-regulation of SALL4 significantly impedes the migration and invasion properties of endometrial cancer cells in vitro and their metastatic potential in vivo. Furthermore, manipulation of SALL4 expression can affect drug sensitivity of endometrial cancer cells to carboplatin. Moreover, we show that SALL4 specifically binds to the c-Myc promoter region in endometrial cancer cells. While down-regulation of SALL4 leads to a decreased expression of c-Myc at both protein and mRNA levels, ectopic SALL4 overexpression causes increased c-Myc protein and mRNA expression, indicating that c-Myc is one of the SALL4 downstream targets in endometrial tumorigenesis. In summary, we are the first to demonstrate that SALL4 plays functional role(s) in metastasis and drug resistance in aggressive endometrial cancer. As a consequence of its functional roles in cancer cell and absence in normal tissue, SALL4 is a potential novel therapeutic target for the high risk endometrial cancer patient population.

Abstract 3479: Sensitivity of endometrial cancer cells to inhibitors targeting different nodes of the PI3K pathway and their combination with a MEK inhibitor.

Abstract Activation of the PI3K pathway has been reported in endometrial cancers, and there are a number of inhibitors targeting different nodes of the PI3K pathway currently in clinical trials, including the PI3K/mTOR dual inhibitor GDC-0980 that is in a phase II trial for endometrial cancer (NCT01455493). In this study, we set to examine the prevalence of overlapping mutational activation of the PI3K pathway with other pathways, such as MAPK. We also tested whether targeting different nodes of PI3K pathway, such as PI3K, AKT, or PI3K/mTOR could exert differential effects on endometrial cancer cells, and whether combination with a MEK inhibitor could provide an additional benefit in inhibiting endometrial cancer cell growth. Alteration of oncogenes and tumor suppressor genes were profiled in 80 endometrial cancer samples by qRT-PCR, targeted deep sequencing, and IHC staining. Multiple PI3K inhibitors, including GDC-0941 (PI3K), GDC-0068 (AKT), GDC-0980 (PI3K/mTOR), and the MEK inhibitor GDC-0973 were tested in a panel of 27 endometrial cancer cell lines for their effects on cell growth. Cell signaling status at baseline and on-treatment was profiled by reverse phase protein array. Mutations and copy number variations of relevant oncogenes and tumor suppressor genes were examined in these cells by targeted deep sequencing. In the 80 endometrial tumor tissues we profiled, there were multiple instances of PI3K pathway alteration including 31% PIK3CA mutations, 9% AKT1 mutations, 16% MET mutations, and 38% PTEN null. In addition, KRAS mutations significantly overlapped with PTEN null or PIK3CA mutation in the same specimen. Endometrial cancer cell lines had distinct patterns of sensitivity to inhibitors targeting different nodes of the PI3K pathway. Preliminary results showed that GDC-0068 was more effective in cell lines with PTEN mutations, while GDC-0941 had a greater effect on those with PIK3CA mutations, and the cell lines were broadly sensitive to GDC-0980. In spite of the widespread activation of the PI3K pathway in endometrial cancer cells, synergistic inhibition of cell growth was observed when GDC-0973 was combined with either GDC-0068 or GDC-0941 in most of the cell lines tested. We will seek to identify genomic and/or proteomic features that will allow better selection as to which node of the PI3K pathway to target, and when to combine with a MEK inhibitor. Citation Format: Matthew J. Wongchenko, Yinghui Guan, Marie-Claire Wagle, Lisa Ryner, Shan Lu, Hartmut Koeppen, Garret Hampton, Mark Lackner, Yulei Wang, Yibing Yan. Sensitivity of endometrial cancer cells to inhibitors targeting different nodes of the PI3K pathway and their combination with a MEK inhibitor. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 3479. doi:10.1158/1538-7445.AM2013-3479

5-Aza-2’-Deoxycytidine Improves the Sensitivity of Endometrial Cancer Cells to Progesterone Therapy

Progesterone has been proven to have limited effects on endometrial cancers (ECs), mainly owing to the down-regulation of progesterone receptor (PR). Here, we explored whether 5-aza-2'-deoxycytidine (5-aza-CdR), a demethylating agent, could enhance the susceptibility of EC cells to medroxyprogesterone acetate (MPA). Ishikawa and KLE cell lines were treated with 5-aza-CdR and/or MPA. The expression of PR, PR target genes, and matrix metalloproteinase (MMP) was investigated by real-time polymerase chain reaction and Western blot. Promoter methylation was detected by methylation-specific polymerase chain reaction. The effects of 5-aza-CdR and/or MPA on cell proliferation, apoptosis, and invasion of EC cells were evaluated by 2-(4-Iodophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium assay, flow cytometry, invasion assay, and gelatin zymography, respectively. 5-Aza-2'-deoxycytidine significantly increased the expression of PR and its downstream targets by demethylating PR promoter in both Ishikawa and KLE cells. 5-Aza-2'-deoxycytidine combined with MPA synergistically suppressed the EC cell growth by inducing cell cycle arrest at G2/M phase and apoptosis. Furthermore, 5-aza-CdR synergized with MPA to inhibit the invasion of EC cells, perhaps owing to the down-regulation of MMP-2 and MMP-9 expression and activity. 5-Aza-2'-deoxycytidine and MPA synergistically inhibit EC cell growth and invasion. Their combined use may provide a new effective therapeutic opportunity for endometrial carcinoma.

Interferon-β increases the sensitivity of endometrial cancer cells to cell-mediated cytotoxicity: Rossiello F.; De Cicco Nardone F.; Dell'Acqua S. ITA Gynecol Oncol 1994 54/2 (130–136)

Interferon-β increases the sensitivity of endometrial cancer cells to cell-mediated cytotoxicity: Rossiello F.; De Cicco Nardone F.; Dell'Acqua S. ITA Gynecol Oncol 1994 54/2 (130–136)

Interferon-β Increases the Sensitivity of Endometrial Cancer Cells to Cell-Mediated Cytotoxicity

Established monolayer cell lines derived from human endometrial carcinoma (Ishikawa and HEC-50) were sensitive to the cytotoxic activity of peripheral blood lymphocytes (PBLs). The percentages of hormone-responsive Ishikawa cells lysed by the cytotoxic activity of lymphocytes were 45.7 ± 4.3 (mean ± SE), 31.5 plusmn; 4.1, and 20.1 ± 1.6, at effector/target (E/T) ratios of 50:1, 25:1, and 12:1, respectively. Values of 44.7 ± 5.4%, 29.4 ± 4.6%, and 20 ± 4.9% were obtained when non-hormone-responsive HEC-50 cells were used as targets at the same E/T ratio. The percentages of epithelial and stromal cells, isolated from human endometrial cancer, lysed by the cytotoxic activity of lymphocytes were 40 ± 5.4 and 23.2 ± 3.8, respectively, at an E/T ratio of 25:1. The addition of interferon-β (IFN-β) to the culture increased tumor target cell sensitivity to the lytic activity of untreated PBL. The increase produced by 10 [U/ml of IFN-β ranged between 0.60- and 0.89-fold (P < 0.01 Student's t test, two-tailed, unpaired) in Ishikawa cells and between 0.37- and 0.72-fold P < 0.05) in HEC-50 cells. Higher concentrations of IFN-β (100 and 1000 IU/ml) were less effective in increasing the sensitivity of the target cells. There was no significant increase in the cytotoxic activity of lymphocytes treated with IFN-β whereas cytotoxic activity toward untreated tumor target cells increased when lymphocytes were treated with IFN-α. The effects of IFN-β were also evaluated using epithelial and stromal cells derived from human endometrial cancer. It was found that IFN-β at low concentrations (10 IU/ml) significantly increased the sensitivity of both epithelial and stromal cells, by 48 and 73%, respectively. Our data indicate that Ishikawa, HEC-50, epithelial, and stromal cells may provide a useful experimental model for studying the effects of immunomodulant agents such as IFN-β in hormone-related tumors. IFN-β increases endometrial target cell sensitivity, rather than the lytic activity of lymphocytes.