Ishikawa Endometrial Cancer Cells Research Articles

Liquid chromatography-high-resolution mass spectrometry-based metabolomics revealing the effects of zearalenone and alpha-zearalenol on human endometrial cancer cells.

Human exposure to mycotoxins through food involve a mixture of compounds, which can be harmful to human health. The Fusarium fungal species are known to produce zearalenone (ZEN), a non-steroidal estrogenic mycotoxin, and its metabolite alpha-zearalenol (α-ZEL), both of which possess endocrine-disruptive properties. Given their potential harm to human health through food exposure, investigating the combined effects of ZEN and α-ZEL becomes crucial. Hence, the combined impact of ZEN and α-ZEL study hold significant importance. This in vitro study delves into the critical area, examining their combined impact on the proliferation and metabolic profile of endometrial cancer Ishikawa cells via sulforhodamine, clonogenic, proliferating cell nuclear antigen (PCNA) and liquid chromatography-high resolution mass spectrometry (LC-HRMS) based untargeted metabolomics. Low concentrations of ZEN (25nm), α-ZEL (10nm), or a combination of both were observed to significantly enhance cell proliferation of Ishikawa cells, as evidenced by PCNA immunostaining, immunoblotting as well and clonogenic assays. The metabolomics revealed the perturbations in glycerophospholipid metabolism, nicotinate and nicotinamide metabolism and phenylalanine, tyrosine, tryptophan biosynthesis provides valuable insights into potential mechanism by which these mycotoxins may facilitate cell proliferation. However, further investigations are warranted to comprehensively understand the implications of these findings and their possible implications for human health.

Aqueous extract of pulp of maqui-berry (Aristotelia chilensis) induces apoptosis in human endometrial carcinoma ishikawa cells via mitochondrial and endoplasmic reticulum stress pathways

In Chilean traditional medicine, Aristotelia chilensis (Mol) Stuntz is commonly utilized for a variety of conditions (particularly digestive problems). We investigated the effects of an aqueous extract from the fruit pulp of A. chilensis (Maqui berry: M2) on endoplasmic reticulum stress and mitochondrial pathway-induced early apoptosis in Ishikawa cells. Using the MTT assay, the aqueous extract was found to have an inhibitory impact on human endometrial cancer Ishikawa cells, with an IC50 of 5.36 μg/mL. The changes in Ishikawa cells under the effect of M2 were detected by flow cytometry with cycle arrest in S phase, reduced mitochondrial membrane potential, ROS and calcium ion aggregation. Western blotting and RT-qPCR were used to identify the intracellular mRNA and protein alterations. The presence of M2 resulted in the up-regulation of mitochondrial pathway-related proteins Bad, Bax, and Cyto C, down-regulation of Bcl-2, and up-regulation of endoplasmic reticulum stress-related proteins IRE1α, p-eif2α, ATF4, and CHOP. The findings imply that A. chilensis pulp may be used as a possible raw material for the innovative functional applications.

Long non-coding RNA JPX promotes endometrial carcinoma progression via janus kinase 2/signal transducer and activator of transcription 3.

Although LncRNA JPX has been linked to a number of malignancies, it is yet unknown how it relates to endometrial carcinoma (EC). Investigating the expression, functional activities, and underlying molecular processes of lncRNA JPX in EC was the goal of this work. RT-qPCR was used to examine the differences in lncRNA/microRNA (miRNA, miR)/mRNA expression between normal cervical and EC tissues or cells. Cell Counting Kit-8, flow cytometry, and transwell were used to evaluate the association between lncRNA JPX/miR-140-3p/phosphoinositide-3-kinase catalytic subunit α (PIK3CA) in Ishikawa and JEC cell lines. The impact of JPX on the downstream janus kinase (JAK)2/signal transducer and activator of transcription (STAT)3 signaling pathway was investigated using Western blot analysis. When comparing EC tissues to nearby normal tissues, JPX expression is markedly increased in EC tissues, with greater expression in advanced-stage EC. Furthermore, compared to normal epithelial cells, EC cell lines have higher levels of JPX expression. In Ishikawa and JEC endometrial cancer cell lines, we used siRNA-mediated suppression of JPX to find lower cell viability, increased apoptosis, cell cycle arrest, and reduced migration and invasion. We next verified that miR-140-3p binds to downstream target cells to impede the transcription and translation of PIK3CA, which in turn prevents the growth of Ishikawa and JEC cells. JPX functions as a ceRNA to adsorb miR-140-3p. This procedure required controlling JAK2/STAT3, a downstream signal. JPX enhances the development of Ishikawa and JEC cells and activates downstream JAK2/STAT3 signal transduction via the miR-140-3p/PIK3CA axis, offering a possible therapeutic target for the treatment of EC.

17β-estradiol Inhibits Oxidative Stress-Induced Apoptosis in Endometrial Cancer Cells by Promoting FOXM1 Expression.

The steroid hormone 17β-estradiol (E2) has a significant impact on the development and progression of tumors. E2 stimulates tumor cell growth and metabolism, leading to an increase in reactive oxygen species (ROS) production. However, the rise in ROS levels is not sufficient to cause severe harm to cancer cells. and the mechanisms that regulate ROS are not well understood. Since FOXM1 plays a crucial role in the production of ROS, we aimed to investigate the impact of E2 on oxidative stress and the involvement of FOXM1 in the Ishikawa endometrial cancer cell line. Our research revealed that E2 controls the levels of ROS inside cells and safeguards them from apoptosis by promoting the expression of FOXM1. We observed a decrease in the expression of FOXM1 alongside an increase in oxidative damage. Moreover, cells demonstrated elevated levels of FOXM1 and ERα upon E2 treatment. Overall, our findings suggest that E2 prevents apoptosis induced by oxidative stress in endometrial cancer cells by encouraging the expression of FOXM1, potentially affecting ERα.

Abstract B004: Investigating loss of ARID1A protein on endometrial cancer progression through the destabilization of adherens junctions

Abstract The purpose of this work is to test the hypothesis that loss of ARID1A promotes endometrial cancer progression by destabilizing tumor cell adherens junctions proteins. ARID1A, an important structural subunit of the SWI/SNF chromatin remodeling complex, is mutated in 26-39% of endometrioid tumors. In endometrial cancer loss of ARID1A has been classically linked to loss of ARID1A expression and has been shown to correlate with increasing tumor grade. However, little is known about the functional impact of ARID1A loss on endometrial cancer progression. A common hallmark of aggressive endometrial cancer is decreased membranous expression of adherens junction proteins, E-Cadherin and β-Catenin. In colorectal and gastric cancer loss of ARID1A expression has been shown to directly downregulate E-Cadherin expression. To determine how loss of ARID1A affects adherens junctions and its impact on endometrial cancer progression we utilized human endometrial cancers and human endometrial cancer cell lines. Using immunohistochemistry, we determined the expression and localization of ARID1A and the adherens junction protein β-Catenin in forty-six human endometrioid type endometrial cancers. Intratumoral heterogeneity of ARID1A expression allowed for quantification of membranous E-Cadherin in relation to presence or absence of ARID1A protein within the same human endometrial tumor. To quantify membranous E-Cadherin we performed immunofluorescence and used line intensity measurements in intratumoral areas of ARID1A presence and ARID1A absence. To assess effects of ARID1A loss on adherens junction in vitro we used short-hairpin RNA to acutely knockdown ARID1A in the endometrial cancer cell lines Ishikawa and ECC-1. Protein expression of ARID1A and E-Cadherin in ARID1A knockdown cells was assessed by Western Blot. Within our cohort of forty-six human endometrial tumors, 75% of tumors with wild-type ARID1A and 45% of tumors with mutated ARID1A had absence of ARID1A protein expression. Due to the discordance between presence of an ARID1A gene mutation and the expression of ARID1A protein, we hypothesize that there are alternative mechanisms of ARID1A protein regulation in endometrial cancer. Additionally, tumors with loss of ARID1A show a trend towards nuclear localization of β-Catenin and have a significant decrease in membranous E-Cadherin expression (P<0.001). However, acute knockdown of ARID1A in Ishikawa and ECC-1 human endometrial cancer cells does not affect total E-Cadherin protein. This suggests that loss of ARID1A may decrease adherens junction stability, as decreased membranous expression of E-Cadherin without total protein change is a common phenotype of destabilized adherens junctions. Thus, we hypothesize that loss of ARID1A destabilizes adherens junctions leading to increased endometrial tumor aggression. Citation Format: Savannah E. Wright, Isurika Weerasinghe, Russell R. Broaddus, Andrew B. Gladden. Investigating loss of ARID1A protein on endometrial cancer progression through the destabilization of adherens junctions [abstract]. In: Proceedings of the AACR Special Conference on Endometrial Cancer: Transforming Care through Science; 2023 Nov 16-18; Boston, Massachusetts. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(5_Suppl):Abstract nr B004.

EphA2- and HDAC-Targeted Combination Therapy in Endometrial Cancer.

Endometrial cancer is the most frequent malignant tumor of the female reproductive tract but lacks effective therapy. EphA2, a receptor tyrosine kinase, is overexpressed by various cancers including endometrial cancer and is associated with poor clinical outcomes. In preclinical models, EphA2-targeted drugs had modest efficacy. To discover potential synergistic partners for EphA2-targeted drugs, we performed a high-throughput drug screen and identified panobinostat, a histone deacetylase inhibitor, as a candidate. We hypothesized that combination therapy with an EphA2 inhibitor and panobinostat leads to synergistic cell death. Indeed, we found that the combination enhanced DNA damage, increased apoptosis, and decreased clonogenic survival in Ishikawa and Hec1A endometrial cancer cells and significantly reduced tumor burden in mouse models of endometrial carcinoma. Upon RNA sequencing, the combination was associated with downregulation of cell survival pathways, including senescence, cyclins, and cell cycle regulators. The Axl-PI3K-Akt-mTOR pathway was also decreased by combination therapy. Together, our results highlight EphA2 and histone deacetylase as promising therapeutic targets for endometrial cancer.

Combined Silencing of VEGF-A and Angiopoietin-2, a More Effective Way to Inhibit the Ishikawa Endometrial Cancer Cell Line [Retraction

[This retracts the article DOI: 10.2147/OTT.S194064.].

Exposure to select PFAS and PFAS mixtures alters response to platinum-based chemotherapy in endometrial cancer cell lines

BackgroundExposure to per- and poly-fluoroalkyl substances (PFAS) has been associated with significant alterations in female reproductive health. These include changes in menstrual cyclicity, timing of menarche and menopause, and fertility outcomes, as well as increased risk of endometriosis, all of which may contribute to an increased risk of endometrial cancer. The effect of PFAS on endometrial cancer cells, specifically altered treatment response and biology, however, remains poorly studied. Like other gynecologic malignancies, a key contributor to lethality in endometrial cancer is resistance to chemotherapeutics, specifically to platinum-based agents that are used as the standard of care for patients with advanced-stage and/or recurrent disease.ObjectivesTo explore the effect of environmental exposures, specifically PFAS, on platinum-based chemotherapy response and mitochondrial function in endometrial cancer.MethodsHEC-1 and Ishikawa endometrial cancer cells were exposed to sub-cytotoxic nanomolar and micromolar concentrations of PFAS/PFAS mixtures and were treated with platinum-based chemotherapy. Survival fraction was measured 48-h post-chemotherapy treatment. Mitochondrial membrane potential was evaluated in both cell lines following exposure to PFAS ± chemotherapy treatment.ResultsHEC-1 and Ishikawa cells displayed differing outcomes after PFAS exposure and chemotherapy treatment. Cells exposed to PFAS appeared to be less sensitive to carboplatin, with instances of increased survival fraction, indicative of platinum resistance, observed in HEC-1 cells. In Ishikawa cells treated with cisplatin, PFAS mixture exposure significantly decreased survival fraction. In both cell lines, increases in mitochondrial membrane potential were observed post-PFAS exposure ± chemotherapy treatment.DiscussionExposure of endometrial cancer cell lines to PFAS/PFAS mixtures had varying effects on response to platinum-based chemotherapies. Increased survival fraction post-PFAS + carboplatin treatment suggests platinum resistance, while decreased survival fraction post-PFAS mixture + cisplatin exposure suggests enhanced therapeutic efficacy. Regardless of chemotherapy sensitivity status, mitochondrial membrane potential findings suggest that PFAS exposure may affect endometrial cancer cell mitochondrial functioning and should be explored further.

Explore the alterations of downstream molecular pathways caused by ARID1A mutation/knockout in human endometrial cancer cells.

As one of the most common gynecologic malignancies, endometrial cancer (EC) is driven by multiple genetic alterations that may be targeted for treatments. AT-rich interaction domain 1A (ARID1A) gene mutations were reported as early events in endometrial carcinogenesis. To explore the alterations of downstream molecular pathways caused by ARID1A mutations and the associated therapeutic implications, we edited ARID1A gene in human endometrial cancer cell line Ishikawa using the Clustered Regularly Interspaced Short Palindromic Repeats and CRISPR-Associated Proteins (CRISPR/Cas9) technology. We successfully constructed a stable Ishikawa cell line with a confirmed 10bp deletion on the ARID1A gene, which resulted in a code-shift mutation and gene knockout. Compared with unedited wild-type cells, ARID1A knockout (KO) led to reduced apoptosis, accelerated transformation from G0/G1 to S phase, and enhanced cell proliferation. ARID1A deficiency would reduce the protein levels of p21, caspase 7, and caspase 9 in Ishikawa endometrial cancer cells compared with the wild-type cells. In addition, ARID1A KO resulted in high levels of microsatellite instability (MSI-H). Moreover, transcriptomic analyses showed that ARID1A KO can lead to activated phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling. Furthermore, experimental analyses demonstrated that ARID1A KO cells had reduced expression of genetic instability-associated markers mutL homologue 1 (MLH1) and progesterone receptor B (PR) and increased p-Akt expression. These findings support further exploration of ARID1A as a therapeutic target for EC and provide insight into developing more effective treatments in EC, such as the combinatory use of immune checkpoint inhibitors.

Prolidase-proline oxidase axis is engaged in apoptosis induction by birch buds flavonol santin in endometrial adenocarcinoma cell line.

Cancer of the corpus uteri and cervix uteri, collectively ranks second among new cancer cases in women after breast cancer. Therefore, investigation of new anticancer agents and identifying new molecular targets presents a challenge to improve effectiveness of chemotherapy. In this study, antiproliferative activity of flavonoids derived from the buds of silver birch and downy birch was evaluated in endometrial cancer Ishikawa cells and cervical cancer HeLa cells. It was found that flavanol santin reduced viability of both cell lines better than other flavonoids, including apigenin and luteolin. Moreover, this activity was slightly higher than that induced by the chemotherapy drug, cisplatin. Santin promoted intrinsic and extrinsic apoptosis pathways in cancer cells, but it had low toxicity in normal fibroblasts. The mechanisms of impairing cancer cell viability included induction of oxidative proline catabolism, however in different ways in the cell lines used. In HeLa cells, increase of proline oxidation was due to activation of p53 leading to proline oxidase upregulation. In contrast, in Ishikawa cells, having basal proline oxidase level significantly higher than HeLa cells, santin treatment decreased its expression. Nevertheless, proline oxidation was induced in these cells since santin increased expression and activity of prolidase, an enzyme providing proline from protein degradation. In both cell lines, proline oxidation was associated with generation of reactive oxygen species leading to reduction in cell viability. Our findings reveal the involvement of proline oxidase in induction of apoptosis by santin and identify a role of prolidase in proline oxidase-dependent apoptosis.

Flavonoids Quercetin and Kaempferol Are NR4A1 Antagonists and Suppress Endometriosis in Female Mice.

Nuclear receptor 4A1 (NR4A1) plays an important role in endometriosis progression; levels of NR4A1 in endometriotic lesions are higher than in normal endometrium, and substituted bis-indole analogs (NR4A1) antagonists suppress endometriosis progression in mice with endometriosis. In addition, the flavonoids kaempferol and quercetin are natural products that directly bind NR4A1 and significantly repress the intrinsic NR4A1-dependent transcriptional activity in human endometriotic epithelial and stromal cells and Ishikawa endometrial cancer cells. NR4A1 knockdown and inhibition of NR4A1 by kaempferol and quercetin suppressed proliferation of human endometriotic epithelial cells and Ishikawa cells by inhibiting epidermal growth factor receptor/c-Myc/survivin-mediated growth-promoting and survival pathways, The mammalian target of rapamycin (mTOR) signaling and αSMA/CTGF/COL1A1/FN-mediated fibrosis signaling but increasing Thioredoxin domain Containing 5/SESN2-mediated oxidative/estrogen receptors stress signaling. In human endometriotic stromal cells, NR4A1 knockdown and inhibition of NR4A1 by kaempferol and quercetin primarily inhibited mTOR signaling by suppressing proliferation of human endometrial stromal cells. In addition, kaempferol and quercetin treatment also effectively suppressed the growth of endometriotic lesions in mice with endometriosis compared with the vehicle without any body weight changes. Therefore, kaempferol and quercetin are NR4A1 antagonists with potential as nutritional therapy for endometriosis.

Boric Acid Exhibits Anticancer Properties in Human Endometrial Cancer Ishikawa Cells.

Objective This study aims to explore the potential anti-cancer properties of boric acid (BA) in human endometrial cancer Ishikawa cells by assessing its influence on cell viability, apoptosis, oxidative stress, and inflammatory responses. Methods The impact of BA at concentrations ranging from 2.5 to 100 mM on cell viability was assessed in Ishikawa cells and normal fibroblast L929 cells (used as the control) through the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Spectrophotometric measurements were performed to determine the total oxidant status (TOS) and total antioxidant status (TAS) in BA-treated cells, and the oxidative stress index (OSI) was calculated. The enzyme-linked immunosorbent assay (ELISA) was used to measure the levels of cytochrome c and caspase 3, both of which are constituents of the extrinsic apoptotic pathway. Furthermore, changes in the concentrations of pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-α) and interleukin-1beta (IL-1β) in the cells were analyzed using ELISA and immunofluorescence staining. Results The exposure of Ishikawa cells to BA for 24 hours led to a dose-dependent decline in cell viability, with an IC50 value of 40 mM. BA dose-dependently increased cytochrome c and caspase 3 levels in cancer cells. In Ishikawa cells, BA treatment led to a significant elevation in OSI. Moreover, the concentrations of TNF-α and IL-1β exhibited a dose-dependent decrease in BA-treated cells. On the other hand, in L929 cells, BA decreased OSI in a dose-dependent manner but did not change TNF-α and IL-1β levels. Concentrations up to 80 mM had no effect on cell viability and apoptosis, but BA at 80 mM concentration decreased viability and increased cytochrome c and caspase 3 levels in L929 cells. Conclusion BA inhibited cell viability, triggered apoptosis, induced oxidative stress, and suppressed inflammatory responses in endometrial cancer cells. Notably, at its IC50 concentration, BA had no cytotoxic effect on normal fibroblasts. Given its favorable properties, BA may provide a valuable therapeutic option to impede the development and progression of endometrial cancer.

Fusaric acid inhibits cell proliferation and downregulates expressions of toll-like receptors pathway genes in Ishikawa endometrial cancer cells.

Fusaric acid is a derivative of picolinic acid produced by some Fusarium species. In this study, we aimed to determine the mRNA expression and antiproliferative effects of fusaric acid in Ishikawa endometrium cancer cells in signal pathway genes associated with Toll-like receptors (TLRs). The effect of fusaric acid on the viability of Ishikawa cells was evaluated using XTT. After total RNA was isolated from control and dose group cells, cDNA synthesis was performed, and mRNA expression changes of genes involved in the Toll-like signaling pathway were evaluated by real-time reverse-transcription polymerase chain reaction (RT-PCR). The decrease in viability of Ishikawa cells was observed in a time- and dose-dependent manner. The inhibitory concentration (IC50) dose of fusaric acid at the 72nd hour in the Ishikawa cell line was 142.81 µM. When the dose group treated with 125 µM fusaric acid at the 72nd hour was compared with the control group, significantly decreased toll-like receptor 1 (TLR1), TLR2, TLR3, TLR4, TLR5, TLR6, TLR7, TLR8, TLR9, TLR10, and Myeloid differentiation primary response protein 88 (MYD88) gene expressions were observed. Fusaric acid inhibits cell proliferation and downregulates Toll-like receptors pathway gene expression in Ishikawa endometrial cancer cells.

Saikosaponin D exerts cytotoxicity on human endometrial cancer ishikawa cells by inducing apoptosis and inhibiting metastasis through MAPK pathways.

Saikosaponin D (SSD) is one of plant secondary metabolic active substance with effective anti-tumor ability; however, the toxicity of Saikosaponin D on human endometrial cancer Ishikawa cells is still unclear. Our results revealed that SSD displayed cytotoxicity on the Ishikawa cell with an IC50 = 15.69 μM, but was non-toxic to the human normal cell line HEK293. SSD could upregulate p21 and Cyclin B to keep cells in the G2/M stage. In addition, it activated the death receptor and mitochondrion routes to induce apoptosis in Ishikawa cells. The transwell chamber and wound healing results showed that SSD inhibited the cell migration and invasion. In addition, we found that it was closely related to the MAPK cascade pathway, and it could mediate the three classical MAPK pathways to block cell metastasis. In conclusion, SSD could be potentially beneficial as a natural secondary metabolite in preventing and treating endometrial carcinoma.

Endometriyal Hücrelerde Spirulina platensis Ekstresinin Kimyasal Bileşiminin Seçici Sitotoksisitesi: İn Vitro ve İn Siliko Yaklaşım

Microalgae are considered as an ample source of bioactive compounds. These wide variety of chemicals possess promising potential to translate into drug candidates. Hence, the aim of this study is to determine potential anti-cancer effects of Spirulina platensis microalgae extract against endometrial cancer cells. The selective cytotoxic effect and cytotoxicity index of S. platensis microalgae extract on the Ishikawa endometrial cancer cell line, the determination of DNA fragmentation and the change in gene expression levels of apoptosis-related Bad, Poly-ADP Ribose Polymerase-1 (PARP1), p53, Akt1 and caspase-3 signaling proteins were determined. ECV304 human umbilical vein endothelial cell line was used for a control cell line. Cytotoxic effects of 500 μg mL-1 of S. platensis microalgae extract on Ishikawa and ECV304 cells were determined as 43±4.87 % and 22±1.87 % respectively. In order to delineate specific compounds in the extract, GC-MS analysis was further conducted and seven major compounds revealed to be abundantly present. Since DNA fragmentation induced by S. platensis extract might be related interaction of GC-MS identified compounds with PARP1, an in silico analysis was further implemented. Results indicated the presence of a possible PARP1 inhibitory mechanism contributing to the apoptotic response. In conclusion, a possible link between a specific compound found in S. platensis microalgae extract and the cytotoxicity in endometrial cells was formed through combining in vitro and in silico approaches. The result of these approaches has contributed to the identification of potential anti-cancer compound candidates found in S. platensis microalgae extract.

Apigenin, a natural flavonoid, promotes autophagy and ferroptosis in human endometrial carcinoma Ishikawa cells in vitro and in vivo

Apigenin, a natural flavonoid has been reported against a variety of cancer types. However, it is unclear whether apigenin can promote autophagy and ferroptosis in Ishikawa cells. There are few reports on the mechanism of apigenin on autophagy and ferroptosis of endometrial cancer Ishikawa cells. We found that iron accumulation, lipid peroxidation, glutathione consumption, p62, HMOX1, and ferritin were increased, while, solute carrier family 7 member 11 and glutathione peroxidase 4 were decreased. Ferrostatin-1, an iron-death inhibitor could reverse the effects of apigenin in Ishikawa cells. On the other hand, apigenin could promote autophagy via up-regulating Beclin 1, ULK1, ATG5, ATG13, and LC3B and down-regulating AMPK, mTOR, P70S6K, and ATG4. Furthermore, apigenin could inhibit tumor tissue proliferation and restrict tumor growth via ferroptosis in vivo.

Niclosamide causes lysosome-dependent cell death in endometrial cancer cells and tumors.

Endometrial cancer is the most common female cancer showing continuous rise in its incidence and mortality rate. Despite the extensive research efforts in cancer therapeutics, still there is a lack of effective treatment options and the outcome is poor for patients with advanced and recurrent endometrial cancers. In this study, we aimed to evaluate the efficacy of niclosamide (NIC) against endometrial cancer. NIC is an FDA-approved anti-helminthic drug, which has been recently extensively studied as a potent anti-cancerous agent in several cancers. The anti-cancerous activity of NIC was analyzed in-vitro (ANC3A, Hec1B, and Ishikawa endometrial cancer cell lines) by cell viability-, soft agar-, invasion- and migration- assay. The action mechanism of NIC was demonstrated by western blot analysis and immune-fluorescence imaging and validated by specific inhibitors. The in-vivo efficacy of NIC was studied in the Ishikawa xenograft animal model. NIC effectively suppressed the viability (IC50<1 μM), colony formation ability, migration, and invasion of all endometrial cancer cells tested. We demonstrated that NIC inhibited AKT/mTOR signaling pathway and induced apoptosis and autophagy in endometrial cancer cells. Further study demonstrated that although NIC induced autophagosome formation, it inhibits autolysosome formation. In addition, we observed that NIC induced BAX co-localization with lysosome and inhibited Cathepsin B maturation from pro-cathepsin B, thereby inducing the lysosomal membrane permeability and release of hydrolytic enzymes from the lysosome to cytosol, which eventually contributed cell death. NIC also inhibited tumor weight and volume in the Ishikawa xenograft animal model without having any evidence of toxicity. Due to its potent anti-cancerous activity and safety profile, NIC seems to be a promising agent for human endometrial cancer therapeutics.

LncRNA XIST/miR‑129‑2‑3p axis targets CCP110 to regulate the proliferation, invasion and migration of endometrial cancer cells.

Centromere coiled-coil protein 110 (CCP110) plays a role in the development of several types of cancer; however, its regulatory mechanism and role in endometrial cancer is unclear. The present study revealed that CCP110 is regulated by a signaling pathway involving microRNA (miR/miRNA)-129-2-3p and the long non-coding RNA (lncRNA) X-inactive-specific transcript (XIST), and plays a role in controlling the proliferation, migration and invasion of endometrial cancer cells. CCP110 was upregulated in human endometrial cancer tissues, as revealed by immunohistochemistry, and high expression of the protein was related to reduced overall survival of the patients. Genetic knockdown of CCP110 by small interfering RNA promoted apoptosis and suppressed the proliferation, migration, invasion and colony formation of endometrial cancer cells significantly in the endometrial cancer Ishikawa and HEC-1B cell lines, as assessed by flow cytometry, and Cell Counting Kit-8, Transwell and colony formation assays. A bioinformatics analysis and luciferase reporter assay revealed that CCP110 is a target of miR-129-2-3p. Overexpression of miR-129-2-3p mimic fragments inhibited the proliferation, migration and invasion of endometrial cancer cells significantly, while co-overexpression of CCP110 counteracted these inhibitory effects. The expression level of the lncRNA XIST was upregulated significantly in endometrial cancer tissues, as assessed by reverse transcription-quantitative PCR assay, while that of miR-129-2-3p was downregulated significantly. A bioinformatics analysis and luciferase reporter assay showed that XIST could inhibit miR-129-2-3p via a miRNA sponge effect. Furthermore, co-overexpression of XIST antagonized the inhibitory effect of the miR-129-2-3p mimic on the luciferase reporter gene signal and protein expression of CCP110. Co-overexpression of XIST also abolished the inhibitory effect of the miR-129-2-3p mimic on the proliferation, migration and invasion of endometrial cancer cells. Overall, these data identified a novel regulatory mechanism of CCP110 involving XIST and miR-129-2-3p, which affected the development of endometrial carcinoma. CCP110, XIST and miR-129-2-3p could represent novel targets for the clinical treatment of endometrial cancer.

Pentamidine inhibits proliferation, migration and invasion in endometrial cancer via the PI3K/AKT signaling pathway

BackgroundPentamidine has been reported to have many pharmacological effects including anti- protozoal, anti-inflammatory, and anti-tumor activities. The aim of this study is to investigate the potential therapeutic role of Pentamidine and molecular mechanisms of Pentamidine on PI3K/AKT signaling pathway underlying the anti-tumor properties in endometrial cancer.MethodsOur study was carried out in the central laboratory of Harbin Medical University from 2019 to 2021. Human endometrial cancer cell lines Ishikawa and HEC-1A were treated with Pentamidine. The proliferation ability of cells was investigated by MTS and colony formation assays. The cell cycle distribution was detected by flow cytometry. Cell migration and invasion were analyzed by using the wound healing assay and Transwell assay. Western blotting was performed to measure the levels of AKT, p-AKT, MMP-2, and MMP-9.ResultsOur results revealed that treatment of Pentamidine inhibited proliferation, migration and invasion of Ishikawa and HEC-1A endometrial cancer cells. Mechanistic investigation showed that Pentamidine inhibited PI3K/AKT signaling pathway and also reduced the expression of MMP-2 and MMP-9. In addition, co-treatment with PI3K kinase inhibitor LY294002 and Pentamidine leaded to increased repression of cell viability and the protein expression of p-AKT in Ishikawa cells.ConclusionsPentamidine suppresses PI3K/AKT signaling pathway, and inhibits proliferation, migration and invasion of EC cells. These findings suggested that Pentamidine might be a potential candidate for treating EC through PI3K/AKT pathway.

252 (PB032) - DB-1303, a HER2-targeting ADC with a novel DNA topoisomerase I inhibitor, demonstrates a promising safety profile and anti-tumor efficacy with differentiation from DS-8201a

Background: DB-1303 is a novel antibody-drug conjugate comprised of trastuzumab biosimilar, enzymatically cleavable peptide-linker, and a proprietary topoisomerase I inhibitor P1003. It is designed to have high plasma stability, low free payload in circulation and wide therapeutic index. Herein, we describe the preclinical profile of DB-1303, including efficacy, pharmacokinetics, and safety. Material and Methods: In vitro cell growth inhibition and in vivo antitumor activities of DB-1303 were evaluated in several Her2-low tumor cell lines and xenograft models. Tumor-bearing mice were used to assess pharmacokinetic and pharmacodynamic characteristic of DB-1303. The mechanism of action for the efficacy was also evaluated. Plasma stability of DB-1303 was determined with rat, monkey, and human plasma. Pharmacokinetic and safety profiles of DB-1303 were evaluated in cynomolgus monkeys. Results: In vitro, DB-1303 selectively binds to and is endocytosed into the lysosome of HER2-positive cells. DB-1303 causes G2/M cell cycle arrest, induces DNA damage, and inhibits cell proliferation in HER2-expressing cells. Importantly, DB-1303 showed inhibitory activity to Her2 low-expressing CAPAN-1 (pancreatic cancer) and Ishikawa (endometrial cancer) cell lines. Under a coculture condition of HER2-positive KPL-4 cells and HER2-negative MDA-MB-468 cells in vitro, DB-1314 inhibited the proliferation of both cells, demonstrating its bystander effect. In vivo, DB-1303 induced dose-dependent tumor growth inhibition and tumor regression in T-DM1-resistant JIMT-1 xenograft model, HER2 low-expressing Ishikawa xenograft and two HER2-low breast cancer PDX models. A single dosing of DB-1303 in NCI-N87 tumor-bearing mice induced significant DNA damage in tumors, and the Cmax of payload in tumor tissues was about 45-fold higher than that in peripheral blood. Pharmacokinetics and safety profiles of DB-1303 were favorable and the highest non-severely toxic dose was 80 mg/kg in cynomolgus monkey study with Q3W dosing of 3 repeated doses. It’s worth noting that, unlike DS-8201a, no interstitial pneumonia was observed in monkeys during the dosing period and recovery period. The payload P1003 poses very low risk of drug-drug interaction. Following administration of DB-1303, systemic P1003 exposure was low and P1003 was cleared rapidly. Conclusions: DB-1303 exhibited potent antitumor activity in both HER2 positive and HER2 low tumor models with a wide therapeutic window. The stable linker in circulation and fast clearance of P1003 may contribute to the superior safety profile of DB-1303. These studies suggest the potential of DB-1303 to address unmet medical needs in HER2 expressing cancers, especially in HER2 low cancers. At the time of presentation, a first-in-human phase 1/2 study in patients with advanced solid tumors is in progress (NCT05150691). No conflict of interest.