Search Results (15)

Endometrial cancer is one of the most common gynaecological malignancies. Although often diagnosed at an early stage, there is a subset of patients with recurrent and metastatic disease for whom current treatments are not effective. Cancer stem cells (CSCs) play a pivotal role in triggering tumorigenesis, disease progression, recurrence, and metastasis, as high aldehyde dehydrogenase (ALDH) activity is associated with invasiveness and chemotherapy resistance. Therefore, this study aimed to evaluate the effects of ALDH inhibition in endometrial CSCs. ECC-1 and RL95-2 cells were submitted to a sphere-forming protocol to obtain endometrial CSCs. ALDH inhibition was evaluated through ALDH activity and expression, sphere-forming capacity, self-renewal, projection area, and CD133, CD44, CD24, and P53 expression. A mass spectrometry-based proteomic study was performed to determine the proteomic profile of endometrial cancer cells upon N,N-diethylaminobenzaldehyde (DEAB). DEAB reduced ALDH activity and expression, along with a significant decrease in sphere-forming capacity and projection area, with increased CD133 expression. Additionally, DEAB modulated P53 expression. Endometrial cancer cells display a distinct proteomic profile upon DEAB, sharing 75 up-regulated and 30 down-regulated proteins. In conclusion, DEAB inhibits ALDH activity and expression, influencing endometrial CSC phenotype. Furthermore, ALDH18A1, SdhA, and UBAP2L should be explored as novel molecular targets for endometrial cancer. Full article

Atractylenolide II (AT-II), the major bioactive compound of Atractylodes macrocephala, exhibits anti-cancer activity against many types of tumors, but the roles and the potential mechanisms in endometrial cancer remain unclear. In the present study, AT-II treatment was found to significantly suppress RL95-2 and AN3CA cell proliferation and glycolysis, and induced their apoptosis by inactivating the ERK signaling pathway, accompanied by the changing expression of the glycolytic key enzymes and apoptotic-related proteins. Peptidyl arginine deiminase 3 (PADI3), as the candidate target gene of AT-II, was highly expressed in the endometrial cancer tissues and associated with a poor prognosis according to bioinformatics analysis. PADI3 knockdown inhibited proliferation and glycolysis in endometrial cancer cells and induced cell apoptosis. Furthermore, AT-II negatively regulated the expression of PADI3, and PADI3 overexpression reversed the effects of AT-II on endometrial cancer cells. Our findings suggested that the anti-cancer function of AT-II is associated with the suppression of glycolysis and induction of apoptosis by blocking the PADI3-ERK signaling pathway. Thus, AT-II represents a novel therapeutic target for endometrial cancer and targeting AT-II may serve as a potential strategy for the clinical therapy of endometrial cancer. Full article

The management of advanced or recurrent endometrial cancers presents a challenge due to the development of resistance to treatments. The knowledge regarding the role of the tumor microenvironment (TME) in determining the disease’s progression and treatment outcome has evolved in recent years. As a TME component, cancer-associated fibroblasts (CAFs) are essential in developing drug-induced resistance in various solid tumors, including endometrial cancers. Hence, an unmet need exists to test the role of endometrial CAF in overcoming the roadblock of resistance in endometrial cancers. We present a novel tumor–TME two-cell ex vivo model to test CAF’s role in resisting the anti-tumor drug, paclitaxel. Endometrial CAFs, both NCAFs (tumor-adjacent normal-tissue-derived CAFs) and TCAFs (tumor-tissue-derived CAFs) were validated by their expression markers. Both TCAFs and NCAFs expressed positive markers of CAF, including SMA, FAP, and S100A4, in varying degrees depending on the patients, while they consistently lacked the negative marker of CAF, EpCAM, as tested via flow cytometry and ICC. CAFs expressed TE-7 and immune marker, PD-L1, via ICC. CAFs better resisted the growth inhibitory effect of paclitaxel on endometrial tumor cells in 2D and 3D formats compared to the resistance of the tumoricidal effect of paclitaxel in the absence of CAFs. TCAF resisted the growth inhibitory effect of paclitaxel on endometrial AN3CA and RL-95-2 cells in an HyCC 3D format. Since NCAF similarly resisted the growth inhibitor action of paclitaxel, we tested NCAF and TCAF from the same patient to demonstrate the protective action of NCAF and TCAF in resisting the tumoricidal effect of paclitaxel in AN3CA in both 2D and 3D matrigel formats. Using this hybrid co-culture CAF and tumor cells, we established a patient-specific, laboratory-friendly, cost-effective, and time-sensitive model system to test drug resistance. The model will help test the role of CAFs in developing drug resistance and contribute to understanding tumor cell-CAF dialogue in gynecological cancers and beyond. Full article

Progestin resistance is a major obstacle to conservative therapy in patients with endometrial cancer (EC) and endometrial atypical hyperplasia (EAH). However, the related inducing factor is yet unclear. In this study, thyroid hormone and its receptor α (TRα) and β (TRβ) of patients were assayed. THRB-silenced RL95-2 and KLE EC cells were cultured to investigate the response of progestins. Transcriptomics and Western blotting were performed to investigate the changes in signaling pathways. We found that THRB, rather than THRA, knockdown promoted the viability and motilities of RL95-2 cells but not KLE cells. The suppressive effect of progestins on cell growth and motility significantly decreased in THRB-silenced RL95-2 cells. Multiple proliferation-related signaling pathways were enriched, and the activities of mammalian targets of rapamycin (mTOR)/4e-binding protein 1 (4EBP1)/eukaryotic translation initiation factor 4G (eIF4G) rather than phosphorylated protein kinase B (Akt) were remarkably boosted. Progestin treatment enhanced the effects, and the augmentation was partially abated on supplementation with T3. In THRB-knockdown KLE cells, the progestins-activated partial signaling pathway expression (either mTOR or eIF4G), and supplementation with T3 did not induce noticeable alterations. The serum levels of triiodothyronine (T3) were significantly lower in patients with EC compared with healthy women. A strong expression of TRβ was observed in most patients with EC and EAH sensitive to progestin treatment. In contrast, TRα positive expression was detected in less than half of the patients sensitive to progestin therapy. In conclusion, THRB knockdown enhanced the viability and motility of type I EC cells and attenuated the suppressive effects of progestins by activating the mTOR-4EBP1/eIF4G pathway. Lower expression of THRB is likely correlated with progesterone resistance. Full article

Endometrial cancer is the most common gynecological cancer worldwide. At present there is no effective screening test for its early detection and no curative treatment for women with advanced-stage or recurrent disease. Overexpression of fatty acid synthase is a common molecular feature of a subgroup of sex steroid-related cancers associated with poor prognoses, including endometrial cancers. Disruption of this fatty acid synthesis leads to cell apoptosis, making it a potential therapeutic target. The saturated fatty acid palmitate reportedly induces lipotoxicity and cell death by inducing oxidative stress in many cell types. Here, we explored the effects of palmitate combined with doxorubicin or cisplatin in the HEC-1-A and RL95-2 human endometrial cancer cell lines. The results showed that physiological concentrations of exogenous palmitate significantly increased cell cycle arrest, DNA damage, autophagy, and apoptosis in both RL95-2 and HEC-1-A cells. It also increased the chemosensitivity of both cell types. Notably, we did not observe that palmitate lipotoxicity reflected increased levels of reactive oxygen species, suggesting palmitate acts via a different mechanism in endometrial cancer. This study thus provides a potential therapeutic strategy in which palmitate is used as an adjuvant in the treatment of endometrial cancer. Full article

Endometrial cancer is the most common malignant tumors of gynecologic neoplasms in Western society. In recent years, the incidence of endometrial cancer has increased, and it has become the third most common female gynecological cancer (after ovarian and cervical cancer) in Taiwan. Adlay (Coix lachryma-jobi L. var. Ma-yuen Stapf.) has been demonstrated to have bioactive polyphenols, flavonoids, phytosterols, and essential nutrients for health benefits, including anticancer effects in humans. However, little is known about the effect of adlay seeds on endometrial cancer. Our study aimed to investigate the potential growth inhibitory effects of several adlay seed fractions, including ethyl acetate (ATE-EA) and its bioactive constituents, separately on endometrial cancer cells—HEC-1A (phosphatase and tensin homolog-positive) and RL95-2 (phosphatase and tensin homolog-negative)—and identify related active ingredients. In addition, the potential active fractions and the phytochemical compounds were elucidated. The results demonstrate superior activity of ATE-EA with significant in vitro cell proliferation inhibitory capacity, particularly its C.D.E.F-subfraction. Moreover, HPLC- and GC/FID-based quantification of ATE-EA subfractions showed that phenolic compounds (caffeic acid, protocatechuic acid, and p-hydroxybenzaldehyde), flavonoids, steroids, and fatty acid compounds exert anti-proliferative effects in the cell model. Finally, it was shown that cell growth and cell cycle arrest most significantly occurred in the in G1 or G2/M phase under ATE-EA treatment. Collectively, our results demonstrate an antiproliferative effect of ATE-EA on endometrial cancer cells that suggest a positive health outcome for women from consumption of these compounds. Full article

Endometrial cancer is a common gynecological cancer with a poor prognosis, mostly attributed to tumor metastasis. Epithelial–mesenchymal transition (EMT) can be mediated via transforming growth factor beta (TGF-β) signaling pathway, facilitating the ability of cancer cell invasion and migration. Isoliquiritigenin (ISL) is a flavonoid derived from licorice with reported antineoplastic activities. This study aims to investigate the anti-metastatic potential of ISL on endometrial cancer both in vitro and in vivo. First, human endometrial cancer cell lines (HEC-1A, Ishikawa, and RL95-2) were treated with ISL and then subjected to functional assays such as migration assay as well as molecular analyses including immunoblotting, immunofluorescence and RT-qPCR. In addition, HEC-1A-LUC cells were implanted into female nude mice and treated with ISL by intraperitoneal injection for four weeks. Results showed that ISL inhibited cell migration and reversed the effect of TGF-β on the expression of E-cadherin, N-cadherin, vimentin, α-SMA, p-Smad3, and TWIST1/2 In vitro. Interestingly, In vivo study revealed that ISL reduced peritoneal dissemination and serum level of TGF-β1, as well as decreased the expression levels of N-cadherin, p-Smad2/3, TWIST1/2, while increased E-cadherin. Overall, ISL reverses the EMT through targeting the TGF-β/Smad signaling pathway and features a potential therapeutic treatment for metastatic endometrial cancer. Full article

Although endometrial carcinoma is one of the most common gynecological malignancies worldwide, its precise etiology remains unknown. Moreover, no novel adjuvant and/or targeted therapies are currently being developed to achieve greater efficacy for endometrial cancer patients who develop chemotherapeutic drug resistance. In this study, we used three human endometrial cancer cell lines, RL95-2, HEC-1-A, and KLE, to investigate the responsiveness of cisplatin alone and in combination with potential repurposed drugs. We first found that RL95-2 cells were more sensitive to cisplatin than HEC-1-A or KLE cells. The cytotoxicity of cisplatin in RL95-2 cells may reflect its ability to perturb the cell cycle, reactive oxygen species production and autophagy as well as to induce senescence and DNA damage. Similar effects, although not DNA damage, were also observed in HEC-1-A and KLE cells. In addition, downregulation of p53 and/or cyclin D1 may also impact the responsiveness of HEC-1-A and KLE cells to cisplatin. We also observed that resveratrol, trichostatin A (TSA), caffeine, or digoxin increased the apoptotic process of cisplatin toward RL95-2 cells, while amiodarone or TSA increased its apoptotic process toward HEC-1-A cells. The combination index supported the assertion that the combination of cisplatin with caffeine, amiodarone, resveratrol, metformin, digoxin, or TSA increases the cytotoxicity of cisplatin in HEC-1-A cells. These findings suggest potential strategies for enhancing the efficacy of cisplatin to overcome drug resistance in endometrial carcinoma patients. Full article

This study investigated the effect of a novel progestin and its combination with metformin on the growth of endometrial cancer (EC) cells. Inhibitory effects of four progestins, including nomegestrol acetate (NOMAC), medroxyprogesterone acetate, levonorgestrel, and cyproterone acetate, were evaluated in RL95-2, HEC-1A, and KLE cells using cell counting kit-8 assay. Flow cytometry was performed to detect cell cycle and apoptosis. The activity of Akt (protein kinase B), mTOR (mammalian target of rapamycin) and its downstream substrates 4EBP1 (4E-binding protein 1) and eIF4G (Eukaryotic translation initiation factor 4G) were assayed by Western blotting. Nude mice were used to assess antitumor effects in vivo. NOMAC inhibited the growth of RL95-2 and HEC-1A cells, accompanied by arresting the cell cycle at G0/G1 phase, inducing apoptosis, and markedly down-regulating the level of phosphorylated mTOR/4EBP1/eIF4G in both cell lines (p < 0.05). Metformin significantly increased the inhibitory effect of and apoptosis induced by NOMAC and strengthened the depressive effect of NOMAC on activity of mTOR and its downstream substrates, compared to their treatment alone (p < 0.05). In xenograft tumor tissues, metformin (100 mg/kg) enhanced the suppressive effect of NOMAC (100 mg/kg) on mTOR signaling and increased the average concentration of NOMAC by nearly 1.6 times compared to NOMAC treatment alone. Taken together, NOMAC suppressing the growth of EC cells likely correlates to down-regulating the activity of the mTOR pathway and metformin could strengthen this effect. Our findings open a new window for the selection of progestins in hormone therapy of EC. Full article

The aim of this study is to investigate the potential inhibitory effect of α-chaconine and α-solanine on RL95-2 estrogen receptor (ER) positive human endometrial cancer cell line and to identify the effect of these glycoalkaloids on the Akt signaling and ERα. The cell proliferation profiles and the cytotoxicity studies were performed by Real-Time Cell Analyzer (xCELLigence) and compared with Sulphorhodamine B (SRB) assay. The effects of α-chaconine (2.5, 5, 10 µM), α-solanine (20, 30, 50 µM), API-1 (25 µM) and MPP (20 µM) effects on Akt (Ser473) and ERα (Ser167) expressions evaluated by Western blot and qPCR method. Their IC₅₀ values were as α-chaconine (4.72 µM) < MPP (20.01 µM) < α-solanine (26.27 µM) < API-1 (56.67 µM). 10 μM α-chaconine and 20, 30 and 50 μM α-solanine were effective in decreasing p-Akt(Ser473)/Akt ratio compared to positive control API-1. When the p-ERα/ERα ratios were evaluated, it was observed that α-chaconine (2.5, 5, 10 μM) and α-solanine (50 μM) were as effective as the specific ERα inhibitor MPP in reducing the ratio of p-ERα/ERα compared to the control group. In conclusion, it has been shown that the proliferation of α-chaconine and α-solanine in human endometrial carcinoma cells reduces the expression and activity of the Akt and ERα signaling pathway. Full article

Endometrial cancer is one of the most common cancer types among women in the world. In our study, it was aimed to investigate the potential anticancer effect of α-chaconine, which is one of the major glycoalkaloids found in Solanum tuberosum (potato), on estrogen receptor (ER) positive endometrial cancer cell line RL95-2. The effect of α-chaconine on RL95-2 cell viability was determined by the method of sulforhodamine B. Effect of α-chaconine on cell growth curve was assessed with the real-time cell analyzer system (xcelligence). The ERα inhibitor methyl-piperidino-pyrazole (MPP) dihydrochloride was used as a positive control to evaluate the association of α-chaconine with ERα. Expressions of ERα and p-ERα protein level were investigated by western blot. ERα mRNA expressions were performed by the real-time PCR method. The IC₅₀ values ​​ of MPP dihydrochloride and α-chaconine were calculated as 20.01 μM and 4.72 μM, respectively. At MPP dihydrochloride 20 μM (p < 0.001), α-chaconine; 2.5 (p < 0.001); 5 (p < 0.001) and 10 μM (p < 0.001) concentrations, p-ERα/ERα ratio was decreased in the same significance compared to control. α-Chaconine decreased the level of ERα mRNA expression, after 24 h, but this decrease was not significant. This study showed for the first time the effect of α-chaconine on cell proliferation, ERα activity and expression in RL95-2 cells. Full article

Nomegestrol acetate (NOMAC) has been successfully used for the treatment of some gynecological disorders, and as a combined oral contraceptive with approval in many countries. In this study, we investigated the effects of NOMAC on human endometrial cancer cells in vitro and in vivo. The proliferation of human endometrial cancer cells (RL95-2 and KLE) were assessed using CCK-8 and EdU incorporation assays. Whole-genome cDNA microarray analysis was used to identify the effects of NOMAC on gene expression profiles in RL95-2 cells. RL95-2 xenograft nude mice were treated with NOMAC (50, 100, and 200 mg/kg) or medroxyprogesterone acetate (MPA; 100 and 200 mg/kg) for 28 consecutive days. The results showed that NOMAC significantly inhibited the growth of RL95-2 cells in a concentration-dependent manner, but not in KLE cells. Further investigation demonstrated that NOMAC produced a stronger inhibition of tumor growth (inhibition rates for 50, 100, and 200 mg/kg NOMAC were 24.74%, 47.04%, and 58.06%, respectively) than did MPA (inhibition rates for 100 and 200 mg/kg MPA were 41.06% and 27.01%, respectively) in the nude mice bearing the cell line of RL95-2. NOMAC altered the expression of several genes related to cancer cell proliferation, including SUFU and Wnt7a. The upregulation of SUFU and Wnt7a was confirmed using real-time quantitative polymerase chain reaction and Western blotting in RL95-2 cells and RL95-2 xenograft tumor tissues, but not in KLE cells. These data indicate that NOMAC can inhibit the proliferation of RL95-2 cell in vitro and suppress the growth of xenografts in the nude mice bearing the cell line of RL95-2 in vivo. This effect could be related to the upregulating expression of SUFU and Wnt7a. Full article

Type II endometrial carcinoma typically exhibits aggressive metastasis and results in a poor prognosis. Siegesbeckia orientalis Linne is a traditional Chinese medicinal herb with several medicinal benefits, including the cytotoxicity against various cancers. This study investigates the inhibitory effects of S. orientalis ethanol extract (SOE) on the migration and invasion of endometrial cancer cells, which were stimulated by transforming growth factor β (TGFβ). The inhibitory effects were evaluated by determining wound healing and performing the Boyden chamber assay. This study reveals that SOE can inhibit TGFβ1-induced cell wound healing, cell migration, and cell invasion in a dose-dependent manner in RL95-2 and HEC-1A endometrial cancer cells. SOE also reversed the TGFβ1-induced epithelial-mesenchymal transition, including the loss of the cell-cell junction and the lamellipodia-like structures. Western blot analysis revealed that SOE inhibited the phosphorylation of ERK1/2, JNK1/2, and Akt, as well as the expression of MMP-9, MMP-2, and u-PA in RL95-2 cells dose-dependently. The results of this investigation suggest that SOE is a potential anti-metastatic agent against human endometrial tumors. Full article

Endometrial cancer is a common malignancy of the female genital tract. This study demonstrates that Siegesbeckia orientalis ethanol extract (SOE) significantly inhibited the proliferation of RL95-2 human endometrial cancer cells. Treating RL95-2 cells with SOE caused cell arrest in the G2/M phase and induced apoptosis of RL95-2 cells by up-regulating Bad, Bak and Bax protein expression and down-regulation of Bcl-2 and Bcl-xL protein expression. Treatment with SOE increased protein expression of caspase-3, -8 and -9 dose-dependently, indicating that apoptosis was through the intrinsic and extrinsic apoptotic pathways. Moreover, SOE was also effective against A549 (lung cancer), Hep G2 (hepatoma), FaDu (pharynx squamous cancer), MDA-MB-231 (breast cancer), and especially on LNCaP (prostate cancer) cell lines. In total, 10 constituents of SOE were identified by Gas chromatography-mass analysis. Caryophyllene oxide and caryophyllene are largely responsible for most cytotoxic activity of SOE against RL95-2 cells. Overall, this study suggests that SOE is a promising anticancer agent for treating endometrial cancer. Full article

Alternative strategies beyond current chemotherapy and radiation therapy regimens are needed in the treatment of advanced stage and recurrent endometrial cancers. There is considerable promise for biologic agents targeting the extracellular signal-regulated kinase (ERK) pathway for treatment of these cancers. Many downstream substrates of the ERK signaling pathway, such as glycogen synthase kinase 3β (GSK3β), and their roles in endometrial carcinogenesis have not yet been investigated. In this study, we tested the importance of GSK3β inhibition in endometrial cancer cell lines and in vivo models. Inhibition of GSK3β by either lithium chloride (LiCl) or specific GSK3β inhibitor VIII showed cytostatic and cytotoxic effects on multiple endometrial cancer cell lines, with little effect on the immortalized normal endometrial cell line. Flow cytometry and immunofluorescence revealed a G2/M cell cycle arrest in both type I (AN3CA, KLE, and RL952) and type II (ARK1) endometrial cancer cell lines. In addition, LiCl pre-treatment sensitized AN3CA cells to the chemotherapy agent paclitaxel. Administration of LiCl to AN3CA tumor-bearing mice resulted in partial or complete regression of some tumors. Thus, GSK3β activity is associated with endometrial cancer tumorigenesis and its pharmacologic inhibition reduces cell proliferation and tumor growth. Full article