Overexpression Of Cyclooxygenase-2 Research Articles

To study the utility of COX-2 as immunohistochemical prognostic marker in comparison to various histopathological parameters and TNM staging in breast carcinoma: an observational, cross-sectional study protocol

Background: Breast cancer is the most prevalent cancer among women worldwide and is a well-known cause for cancer mortality in females. COX-2 (cyclooxygenase) plays a vital role in development of some human cancers such as lung, colon and breast. It is a potent enzyme that is important for the conversion of arachidonic acid into prostaglandins. These prostaglandins mediate cellular proliferation, apoptosis and angiogenesis which contributes to carcinogenesis. Overexpression of COX-2 has been detected in several malignancies including breast cancer. COX-2 overexpression is regarded as a poor prognostic marker of breast cancer. The present study will aim to study the immunohistochemical expression of COX-2 in breast cancer and compare it with known histopathological parameters thus assessing its prognostic value. Methods: This will be an observational study conducted in the Department of Pathology, JNMC, Wardha (Sawangi). Radical mastectomy specimens will be studied for COX-2 expression by immunohistochemistry in patients diagnosed with breast carcinoma. COX-2 expression will be quantified as immunohistochemical score and results will be correlated with various histopathological parameters. Results: The expected result of our study will suggest an association of COX-2 expression to the factors associated with poor prognosis in breast carcinoma. A positive correlation is expected between larger tumor size, positive lymph node status, higher T stage and N stage and lymphovascular invasion. Conclusions: Conclusions will be drawn from the obtained results of the immunohistochemical study by using COX-2- for detection of overexpression of COX-2 when evaluated with TNM staging, histological grading and molecular types of breast cancer.

A Combination of Polymethoxyflavones from Citrus sinensis and Prenylflavonoids from Humulus lupulus Counteracts IL-1β-Induced Differentiated Caco-2 Cells Dysfunction via a Modulation of NF-κB/Nrf2 Activation.

We here investigated the anti-inflammatory activity of a polymethoxylated flavone-containing fraction (PMFF) from Citrus sinensis and of a prenylflavonoid-containing one (PFF) from Humulus lupulus, either alone or in combination (MIX). To this end, an in vitro model of inflammatory bowel disease (IBD), consisting of differentiated, interleukin (IL)-1β-stimulated Caco-2 cells, was employed. We demonstrated that non-cytotoxic concentrations of either PMFF or PFF or MIX reduced nitric oxide (NO) production while PFF and MIX, but not PMFF, also inhibited prostaglandin E2 release. Coherently, MIX suppressed both inducible NO synthase and cyclooxygenase-2 over-expression besides NF-κB activation. Moreover, MIX increased nuclear factor erythroid 2-related factor 2 (Nrf2) activation, heme oxygenase-1 expression, restoring GSH and reactive oxygen and nitrogen species (RONs) levels. Remarkably, these effects with MIX were stronger than those produced by PMFF or PFF alone. Noteworthy, nobiletin (NOB) and xanthohumol (XTM), two of the most represented phytochemicals in PMFF and PFF, respectively, synergistically inhibited RONs production. Overall, our results demonstrate that MIX enhances the anti-inflammatory and anti-oxidative effects of the individual fractions in a model of IBD, via a mechanism involving modulation of NF-κB and Nrf2 signalling. Synergistic interactions between NOB and XTM emerge as a relevant aspect underlying this evidence.

Association of cyclooxygenase-2 expression with endoplasmic reticulum stress and autophagy in triple-negative breast cancer.

Cyclooxygenase-2 plays a role in oncogenesis and its overexpression is associated with triple-negative breast cancer. However, the mechanisms whereby cyclooxygenase-2 contribute to breast cancer are complex and not well understood. Cyclooxygenase-2 overexpression causes hypoxia, oxidative stress, and endoplasmic reticulum stress. The aim of this study is to investigate the correlations among cyclooxygenase-2 expression, endoplasmic reticulum stress-associated molecules, and autophagy-associated molecules in triple-negative breast cancer. Surgical specimens from two cohorts of triple-negative breast cancer patients without neoadjuvant systemic therapy were analyzed: cohorts 1 and 2 consisted of 218 cases from 2004 to 2006 and 221 cases from 2007 to 2009, respectively. Specimens were evaluated by immunohistochemical examination of cyclooxygenase-2, endoplasmic reticulum stress markers, and autophagy markers expression using tissue microarrays. Cyclooxygenase-2 was overexpressed in 29.8% and 23.9% of cases in cohorts 1 and 2, respectively; and it was positively correlated with two out of three endoplasmic reticulum stress-associated molecules (XBP1, p = 0.025 and p = 0.003 in cohort 1 and cohort 2, respectively; PERK, p < 0.001 in both cohorts). Cyclooxygenase-2 was also positively correlated with two out of three autophagy markers (p62, p = 0.002 and p = 0.003 in cohort 1 and cohort 2, respectively; beclin1, p < 0.001 in both cohorts). Although cyclooxygenase-2 was not an independent prognostic factor for distant metastasis free survival and overall survival, its expression was associated with the expression of endoplasmic reticulum stress and autophagy molecules in triple-negative breast cancer.

Self-assembly nanoplatform of platinum (Ⅳ) prodrug for enhanced ovarian cancer therapy.

Cisplatin is a metal platinum complex commonly used in the field of anti-tumor and one of the most commonly used drugs in combination chemotherapy. However, chemotherapy with Cisplatin induced overexpression of cyclooxygenase-2 (COX-2) protein in tumor cells, which could impair the therapeutic effect of chemotherapy on tumor progression. Here, we presented a novel method for the treatment of ovarian cancer with a self-assembly based nano-system. Cisplatin and tolfenamic acid were each linked to linoleic acid to give them the ability to self-assemble into nanoparticles in water. TPNPs had flexible drug ratio adjustability, homogeneous stability, and high drug loading capacity. Compared with Cisplatin, TPNPs could promote cellular uptake and tumor aggregation, co-induce enhanced apoptosis and tumor growth inhibition by inhibiting COX-2 in the mice xenograft model of human ovarian cancer, and reduce systemic toxicity. Therefore, TPNPs is a promising antitumor drug as a kind of self-assembly nano-prodrug with high drug load.

Design of novel anti-cancer agents targeting COX-2 inhibitors based on computational studies

The overexpression of cyclooxygenase-2 (COX-2) was clearly associated with carcinogenesis, and COX-2 as a possible target has long been exploited for cancer therapy. A group of 29 derivatives of 1, 5-diarylpyrazole was used to study its structural requirements using three-dimensional quantitative structure–activity relationship (3D-QSAR), the density functional theory method, molecular docking, and molecular dynamics. Four 3D-QSAR models were developed, and the predictive capability of the four selected models was also successfully tested using different validation methods. The contribution contours of the comparative molecular field analysis (CoMFA) and comparative molecular similarity index analysis (CoMSIA) models effectively illustrate the relationships between the various chemical characteristics and their biological activities. Using the density functional theory method with the 6-31G (d, p) basis set and the Becke, 3-parameter, Lee-Yang-Parr (B3LYP) function to evaluate chemical reactivity properties, the results obtained from energy gaps of 3.431, 3.446, and 2.727 ev for molecules numbers 21, 22, and 23 indicate that these three molecules have good chemical stability and reactivity and select the most reactive regions in the three molecules studied. Molecular docking results revealed that the active sites of the COX-2 protein (PDB code: 3PGH) were residues ARG222, THR212, HIS386, HIS207, TYR148, and ASP382, in which the most active ligands and now ligands can inhibit the COX-2 enzyme. Based on the various results obtained by molecular modeling, four new compounds (N1, N2, N3, and N4) were proposed with significant predicted activity by different 3D-QSAR models. A molecular docking study and molecular dynamics simulations of the proposed new molecules (N1 and N2) and the most active molecule over 100 ns revealed that all three molecules establish multiple hydrogen interactions with several residues and also exhibit frequent stability throughout the simulation period. As a result, it is strongly recommended to consider the two newly proposed molecules, N1 and N4, as promising candidates for novel anti-cancer agents specifically designed to target COX-2 inhibition.

Small extracellular vesicles from HO-1-modified bone marrow-derived mesenchymal stem cells attenuate ischemia-reperfusion injury after steatotic liver transplantation by suppressing ferroptosis via miR-214-3p

Donor shortage is a major problem that limits liver transplantation availability. Steatotic donor liver presents a feasible strategy to solve this problem. However, severe ischemia-reperfusion injury (IRI) is an obstacle to the adoption of steatotic transplanted livers. Evidence from our prior studies indicated that bone marrow mesenchymal stem cells modified with heme oxygenase-1 (HMSCs) can attenuate non-steatotic liver IRI. However, the contribution of HMSCs in transplanted steatotic liver IRI is unclear. Here, HMSCs and their derived small extracellular vesicles (HM-sEVs) alleviated IRI in transplanted steatotic livers. After liver transplantation, there was significant enrichment of the differentially expressed genes in the glutathione metabolism and ferroptosis pathways, accompanied by ferroptosis marker upregulation. The HMSCs and HM-sEVs suppressed ferroptosis and attenuated IRI in the transplanted steatotic livers. MicroRNA (miRNA) microarray and validation experiments indicated that miR-214-3p, which was abundant in the HM-sEVs, suppressed ferroptosis by targeting cyclooxygenase 2 (COX2). In contrast, COX2 overexpression reversed this effect. Knockdown of miR-214-3p in the HM-sEVs diminished its ability to suppress ferroptosis and protect liver tissues/cells. The findings suggested that HM-sEVs suppressed ferroptosis to attenuate transplanted steatotic liver IRI via the miR-214-3p–COX2 axis.

Ergothioneine inhibits the progression of osteoarthritis via the Sirt6/NF-κB axis both in vitro and in vivo.

Osteoarthritis (OA), which is a major cause of serious arthralgia and disability among the elderly, has long plagued numerous populations. However, the specific molecular mechanisms involved in the etiology of OA are unclear. SIRT6 plays a critical function in the development of several inflammatory and aging-associated diseases. A study by D'Onofrio demonstrates that ergothioneine (EGT) is an effective activator of SIRT6. As revealed by previous reports, EGT exerts beneficial effects on the mouse body, including resistance to oxidation, tumor, and inflammation. Therefore, this work attempted to identify the inflammatory resistance of EGT and explore its effects on the incidence and development of OA. Mouse chondrocyte stimulation using varying levels of EGT and 10ng/mL IL-1β. According to in vitro experiments, EGT significantly reduced the decomposition of collagen II and aggrecan in OA chondrocytes, as well as inhibited the overexpression of PGE2, NO, IL-6, TNF-α, iNOs, COX-2, MMP-13, and ADAMTS5. In the present work, EGT hindered the NF-κB activity by activating the SIRT6 pathway in OA chondrocytes, which in turn, significantly attenuated the inflammatory response resulting from IL to 1β. The inhibitory effect of EGT on the progression of OA was demonstrated by the mouse DMM model experiment. Thus, this study revealed that EGT was effective in anti-OA treatment.

BACH1 encourages ferroptosis by activating KDM4C-mediated COX2 demethylation after cerebral ischemia-reperfusion injury.

It has been confirmed that BTB domain and CNC homologue 1 (BACH1) are involved in ferroptosis-related diseases. However, the function of BACH1 in cerebral ischemia-reperfusion injury (CIRI)-induced ferroptosis remains to be largely unrevealed. First, analysis of differentially expressed genes in CIRI based on the GEO dataset GSE119121 revealed that BACH1 was upregulated in CIRI. BACH1 level was prominently increased in middle cerebral artery occlusion (MCAO)/reperfusion model and oxygen-glucose deprivation/reoxygenation cell model. Further, knock-down of BACH1 markedly reduced iron ion concentration, ROS production, 4-HNE and lipid peroxidation levels and facilitated GSH content, cell viability and protein levels of GPX4 and SLC7A11, while an pcDNA-KDM4C or pcDNA-COX2 combined with BACH1 siRNA could not enhance this effect. Mechanistically, BACH1 bound on the KDM4C promoter to transcriptionally activate its expression. Besides, KDM4C could occupy the promoter locus of the COX2 gene, promoting the COX2 expression by eliminating H3K9me3. Overexpression of KDM4C or COX2 overturned the effects of BACH1 inhibition. In vivo findings displayed that brain infraction, pathological damage and neuronal loss rate in MCAO mice were conspicuously decreased after BACH1 knock-down. This study reveals that BACH1 encourages ferroptosis in neuroblastoma cells and CIRI mouse brain tissues by activating KDM4C-mediated COX2 demethylation.

Hu'po Anshen decoction promotes fracture healing in mice with traumatic brain injury through BMP2-COX2-ATF4 signaling pathway.

Hu'po Anshen decoction (HPASD), a traditional Chinese medicine used to treat concussion and fracture, could regulate the expression of bone morphogenetic protein 2 (BMP2). However, whether HPASD affects the fracture healing of traumatic brain injury (TBI) combined with a fracture through BMP2 and its downstream signals remains obscure. The chondrocyte-specific BMP2 conditional knockout mice and chondrocyte-specific cyclooxygenase-2 (COX2) overexpression mice were generated. BMP2 conditional knockout mice were treated with fracture surgery, fracture combined with TBI, or fracture combined with TBI followed by different doses of HPASD (2.4, 4.8, and 9.6 g/kg), respectively. TBI was induced by Feeney's weight-drop technique. The fracture callus formation and fracture sites were determined by X-ray, micro-CT, and histological analyses. The expressions of chondrocyte-, osteoblast-, and BMP2/COX2 signal-related targets were determined by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blot assays. The specific absence of BMP2 in chondrocytes led to the prolonged formation of cartilage callus, a delay in the osteogenesis initiation and the downregulation of RUNX2, Smad1/5/9, EP4, ERK1/2, RSK2, ATF4. Overexpression of COX2 partially reverses the effects of chondrocyte-specific BMP2 knockout mice. HPASD promoted cartilage callus formation and osteogenesis initiation, as accompanied by upregulated expression levels of RUNX2, Smad1/5/9, EP4, ERK1/2, RSK2, and ATF4 in a time-dependent and concentration-dependent manner in chondrocyte-specific BMP2 knockout mice. Overall, our findings demonstrated that HPASD induced COX2 transcription through the BMP2-Smad1/5/9-RUNX2 axis, and then affected fracture healing through the COX2-mediated EP4-ERK1/2-RSK2-ATF4 axis.

Geiparvarin Inhibits the Progression of Osteosarcoma by Down-regulating COX2 Expression.

Geiparvarin (GN) is a natural compound isolated from the leaves of Geijera parviflora and exhibits anticancer activity. Nevertheless, little is known about its anticancer mechanism and anti-osteosarcoma (OS) effects. This study explored whether GN effectively inhibits the growth and metastasis of osteosarcoma (OS) through a series of in vitro and in vivo experiments. Cell proliferation was measured by colony formation and MTT assays, and cell invasion was detected by Transwell assay. Flow cytometry and caspase-3 activity assays were carried out to examine cell apoptosis, and western blot analysis was performed to assess protein expression. In the animal experiments, the changes in relevant indexes were determined by immunohistochemistry and tumor vessel imaging. Animal experiments showed that GN treatment significantly inhibited the growth and lung metastasis of OS, accompanied by increased apoptosis. In addition, GN treatment notably diminished COX2 expression and angiogenesis in OS. Moreover, COX2 overexpression nullified GN-induced decline in angiogenesis, growth, and lung metastasis and increased apoptosis in OS. Of note, the body weight of mice was enhanced after GN treatment, and the pathological examination manifested that GN treatment did not cause any damage to major organs. Our data indicated that GN might depress the growth, metastasis, and angiogenesis of OS by decreasing COX2 expression, suggesting GN is a favorable candidate drug for OS treatment without side effects. Hence, it can be concluded that geiparvarin inhibits OS progression by reducing COX2 expression.

Abstract 3102: Synthesis of N-benzoylamino-tetrahydropyridine analogues as selective COX-2 inhibitors and anti-breast cancer agents

Abstract The World Health Organization confirms breast cancer as the most common cancer globally, as of 2021, tallying 12% of new annual cancer cases. Female breast cancer is the second leading cancer in incidence rates among women after lung cancer. It is also more deadly amongst Black and Hispanic women as mortality rates increase by 40% compared to their caucasian counterparts. Hence, there is a dire need to design and develop novel molecules as effective anticancer agents. Rational design-based drug discovery has led to advancements in developing novel small molecules as effective anticancer agents. Chronic inflammation is directly related to cancer. Literature testifies to the presence and overexpression of cyclooxygenase-2 (COX-2) in various inflammation-based ailments, diseases, and many cancers. Therefore, it is imperative to investigate the relevance of cyclooxygenase-2 inhibition in cancer therapy. The tetrahydropyridine structure has been documented in several natural products. They display biological properties including antioxidant, anti-inflammatory, and chemotherapeutic. Substituted benzoylamino-5-ethyl-1,2,3,6-tetrahydropyridine analogues have been designed as COX-2 inhibitors. This project aims to synthesize thirteen novel THP analogues using a 4-step synthesis. The synthesis of these 1,2,3,6-THP analogues primarily involves the hydrolysis of ethyl-o-(mesitylenesulfonyl) acethydroxymate to render O-(mesitylsulfonyl)hydroxylamine (MSH). MSH then acts as an aminating agent as it reacts with 3-ethyl pyridine. This amination reaction affords the mesitylene salt, 1-amino-3-ethylpyridin-1-ium. Next, the salt product undergoes acylation with various substituted benzoyl chlorides to generate stable N-ylide products. Finally, the partial reduction of the ylides yields the desired final tetrahydropyridine products. Purification was completed by flash chromatography. The novel THP analogues were characterized using nuclear magnetic resonance, infrared spectroscopy, and elemental analysis. Computer-aided drug design studies provided the preliminary data constituting that the likelihood of the THP moiety generating more effective COX-2 inhibitors is dependent on suitable modifications to the structure. Further studies include testing the novel THP analogues as cyclooxygenase-2 inhibitors using COX-2 inhibition assays, and lastly, determining their anti-breast cancer activity in MDA-MD-231, MCF-7 and Ishikawa cell lines to assess their antiproliferative effects. This research was supported by the National Institute on Minority Health and Health Disparities of the National Institutes of Health under Award Number U54 MD007582. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health. Citation Format: Shasline Gedeon, Madhavi Gangapuram, Kinfe K. Redda, Tiffany Ardley. Synthesis of N-benzoylamino-tetrahydropyridine analogues as selective COX-2 inhibitors and anti-breast cancer agents [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3102.

Abstract 6077: Comprehensive multi-omic characterization of genetic changes associated with sinonasal squamous cell carcinoma progression

Abstract Approximately 50-80% of sinonasal tract cancers are sinonasal squamous cell carcinoma (SNSCC), a rare malignancy which occur in the nasal cavity and maxillary sinus. These lesions possess a propensity for local invasion into adjacent structures including the skull base, brain, and orbit. Owing to relatively mild symptoms during early stages, which resemble benign sinonasal disease, most patients are already in clinically advanced stages when diagnosed. Therefore, despite improvements in endoscopic surgical approaches, radiotherapy and imaging techniques, the 5-year overall survival for advanced SNSCC patients remains poor (~40%). Inverted sinonasal papilloma (IP) is a locally aggressive, benign epithelial neoplasm arising in the paranasal sinuses which has a high recurrence rate and transforms to SNSCC in 10%-25% of cases. As some IP evolve to malignant neoplasms, it has been presumed that they represent an intermediate step in SNSCC progression. However, the current tools for detecting altered epithelial cells, such as clinical examination and histological characteristics, have limited prognostic value for predicting which IP will progress to malignancy, and the link between IP and invasive disease remains unclear. Activating mutations in EGFR and PIK3CA genes as well as loss-of-function mutations in TP53 have been reported in a few very small cohorts of IP and SNSCC lesions, suggesting their role in IP pathogenesis and progression to invasive malignancy. Other observed alterations potentially associated with malignant transition include KRAS mutations, loss of heterozygosity (LOH) at the 9p21 locus (containing p16INK4a), mismatch repair genes deficiency, amplification of FGFR1 and SOX2 genes, as well as NFκB, COX2 and HOXA9 overexpression. While these studies provide a snapshot of molecular changes in SNSCC, genetic alterations critical to the development of SNSCC are poorly understood, and the exact mechanism underlying malignant transformation remains unknown. In this study we have used PandaOmic, a multi-omic data analysis and visualization algorithm, to perform a first comprehensive integrative analysis of WES, mitochondrial sequencing and transcriptomic data obtained from 11 IP lesions, matched invasive SNSCC tumors and histologically normal paranasal sinus epithelium collected from the same patients. Our analysis reveals heterogeneous mutational patterns, gene expression changes and signaling pathways features associated with SNSCC pathogenesis, and provides crucial insights that may aid in the development of novel means of prevention, diagnosis, and treatment of this rare, aggressive and poorly characterized malignancy. Citation Format: Alka Singh, Nikita Babushkin, Michael Korzinkin, Viktoria Sarkisova, Vasudha Mishra, Ari Rosenberg, Mark Lingen, Justin Bishop, Alex Zhavoronkov, Nyall London, Nishant Agrawal, Xuanyao Liu, Evgeny Izumchenko. Comprehensive multi-omic characterization of genetic changes associated with sinonasal squamous cell carcinoma progression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6077.

Potential drugs for the treatment of Alzheimer's disease.

It is well known that amyloid precursor protein (APP), the enzyme β-secretase 1 (BACE1), cyclooxygenase 2 (COX-2), nicastrin (NCT), and hyperphosphorylated tau protein (p-tau) are closely related to the development of Alzheimer's disease (AD). In addition, recent evidence shows that neuroinflammation also contributes to the pathogenesis of AD. Although the mechanism is not clearly known, such inflammation could alter the activity of the aforementioned molecules. Therefore, the use of anti-inflammatory agents could slow the progression of the disease. Nimesulide, resveratrol, and citalopram are three anti-inflammatory agents that could contribute to a decrease in neuroinflammation and consequently to a decrease in the overexpression of APP, BACE1, COX-2, NCT, and p-Tau, as they possess anti-inflammatory effects that could regulate the expression of APP, BACE1, COX-2, NCT, and p-Tau of potent pro-inflammatory markers indirectly involved in the expression of APP, BACE1, NCT, COX-2, and p-Tau; therefore, their use could be beneficial as preventive treatment as well as in the early stages of AD.

Cyclooxygenase-2 as a therapeutic target against human breast cancer: A comprehensive review.

Cyclooxygenase-2 (COX-2) is a key aspect of the physiology and pathogenesis of various cancer types. Overexpression of this enzyme is responsible for the elevated prostaglandin production and characteristic feature of breast cancer. Inhibition of COX-2 derived prostanoids facilitates anti-inflammatory, analgesic, and antipyretic effects of non-steroid anti-inflammation drugs. The overexpression of COX-2 is associated with inflammation, pain, and fever. The present study provides the updated relevant literature describing the role of well-characterized isoforms of cyclooxygenase with particular emphasis on COX-2, mechanism of action, the effect of the drug, combinatorial drugs, and microarray-based differential expression analysis and network analysis. We have discussed the currently used combinatorial treatments and their challenges in breast cancer. This article is categorized under: Cancer > Computational Models Cancer > Molecular and Cellular Physiology.

Role of COX-2/PGE2 signaling pathway in the apoptosis of rat ovarian granulosa cells induced by MEHP

ObjectiveMEHP, as the metabolite of DEHP, is a widely used environmental endocrine disruptor. Ovarian granulosa cells participate in maintaining the function of ovary and COX2/PGE2 pathway may regulate the function of granulosa cells. We aimed to explore how COX-2/PGE2 pathway affects cell apoptosis in ovarian granulosa cells caused by MEHP. MethodsPrimary rat ovarian granulosa cells were treated with MEHP (0, 200, 250, 300 and 350 μM) for 48 h. Adenovirus was used for over-expression of COX-2 gene. The cell viability was tested with CCK8 kits. The apoptosis level was tested by flow cytometry. The levels of PGE2 were tested with ELISA kits. The expression levels of COX-2/PGE2 pathway related genes, ovulation-related genes and apoptosis-related genes, were measured with RT-qPCR and Western blot. ResultsMEHP decreased the cell viability. After MEHP exposure, the cell apoptosis level increased. The level of PGE2 markedly decreased. The expression levels of COX-2/PGE2 pathway related genes, ovulation-related genes and anti-apoptotic genes decreased; the expression levels of pro-apoptotic genes increased. The apoptosis level was alleviated after over-expression of COX-2, and the level of PGE2 slightly increased. The expression levels of PTGER2 and PTGER4, and the levels of ovulation-related genes increased; the levels of pro-apoptotic genes decreased. ConclusionMEHP can cause cell apoptosis by down-regulating the levels of ovulation-related genes via COX-2/PGE2 pathway in rat ovarian granulosa cells.

Novel celecoxib-loaded chitosan-fucoidan nanoparticles as potential immunotherapy for oral squamous cell carcinoma: Mechanistic insights

Celecoxib (CXB), a selective COX-2 inhibitor, is a component of triple-oral-metronomic-chemotherapy. However, chronic CXB utilization in high doses could bring about major cardiovascular consequences. The CXB incorporation into chitosan (CS)/fucoidan (FCD) nanoparticles (NPs) could be expected to reduce drug toxicity, improve epithelial drug permeation, and enhance drug delivery to COX-2 over-expressing sites within TME. CXB-loaded CS/FCD NPs were developed and evaluated for particle size, zeta potential, entrapment efficiency, morphology, and in vitro drug release. SCC-4 cells were used to test the cytotoxic, antiproliferative, and pro-apoptotic effects by performing MTT, Ki-67, and Annexin-V assays, respectively. The selective uptake of CS/FCD NPs by labelled tumor immune cells (TICs), tumor-endothelial-cells (TECs), and myeloid-derived-suppressor-cells (MDSCs) was determined qualitatively and quantitatively. Furthermore, signaling molecules, including Jagged-1/Notch-signaling, and biomarkers of TICs, TECs, and MDSCs; such as TGF-β, IL-6, aldehyde dehydrogenase, and arginase-1/iNOS, were analyzed in harvested SCC-4 cells pre-treated with CXB-CS/FCD-NPs, plain FCD and CXB. The best achieved CXB-CS1FCD5 NPs were spherical in shape, and possessed an optimum size (226.4 nm), promising zeta potential (−26.30 mV), high entrapment efficiency (76.78%), and allowed sustained CXB release. They showed the utmost anti-proliferative, pro-apoptotic and cell-cycle arrest in SCC-4 cells with greater accumulation within MDSCs. Neither FCD nor CXB in their plain form could affect all of the tested TME cellular biomarkers. On contrary, CXB-CS/FCD NPs had significantly affected all of the investigated biomarkers. This study highlighted the synergistic antitumor potential of CXB-CS/FCD NPs against oral cancer, at lower CXB doses, and provided some mechanistic insights that can in part explain the observed anticancer efficacy.

Ginsenoside Rg3 alleviates the migration, invasion, and angiogenesis of lung cancer cells by inhibiting the expressions of cyclooxygenase-2 and vascular endothelial growth factor.

Lung cancer (LC) is a common cancer with high incidence and mortality rates. In recent years, ginsenoside Rg3 (Rg3), a traditional medicine, is widely used for the treatment of LC. Herein, we concentrate on assessing the effect of Rg3 on LC cell migration and invasion. The effects of Rg3 (0, 25, 50, and 100 μg/ml) on the viability, migration, invasion, angiogenesis, and expressions of epithelial-mesenchymal transition (EMT)-related proteins, cyclooxygenase-2 (COX2), and vascular endothelial growth factor (VEGF) of LC cell lines were evaluated by cell counting kit-8 (CCK-8), scratch, transwell, tube formation, and western blot assays. Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to assess transfection efficiency. COX2 overexpression plasmid and short hairpin RNA for VEGF (shVEGF) were applied to evaluate whether the effect of Rg3 is related to COX2 and VEGF through rescue assay. In this study, Rg3 significantly dose-dependently suppressed the viability, migration, invasion, angiogenesis, and protein expressions of N-cadherin, vimentin, COX2, and VEGF in H1299 and A549 cells, while promoting the expression of E-cadherin protein. COX2 overexpression markedly reversed the effects of Rg3 on the viability, migration, invasion, angiogenesis, and EMT-related protein expression levels in LC cells; however, such effects of COX2 overexpression were offset by VEGF knockdown. In sum, Rg3 alleviates the migration, invasion, and angiogenesis of LC cells by inhibiting the expressions of COX2 and VEGF.

LncRNA RMRP aggravates LPS-induced HK-2 cell injury and AKI mice kidney injury by upregulating COX2 protein via targeting ELAVL1

ObjectivesThere is emerging evidence that long non-coding RNA component of mitochondrial RNA processing endoribonuclease (lncRNA RMRP) is involved in acute kidney injury (AKI) progression, but the specific mechanism of action still requires further investigation. MethodsThe lipopolysaccharide (LPS)-treated HK-2 cells were transfected with pcDNA-RMRP or si-RMRP, or transfected with pcDNA-ELAV like RNA binding protein 1 (ELAVL1) or si-ELAVL1, and cell viability, apoptosis, inflammatory factor secretion and oxidative stress were detected. The LPS-treated HK-2 cells were transfected with si-RMRP alone or together with pcDNA-ELAVL1, and cell behaviors were examined. The LPS-treated HK-2 cells were transfected with si-ELAVL1 alone or together with pcDNA- cyclooxygenase-2 (COX2), and the cellular changes were observed. The LPS-treated HK-2 cells were transfected with si-RMRP alone or together with pcDNA-ELAVL1, or together with pcDNA-ELAVL1 and si-COX2, and cell behaviors were examined. A mouse model of AKI was constructed using male C57BL/6 mice by the method of cecal ligation and puncture and intraperitoneal injection of LPS to explore the effect of RMRP silencing on renal injury in vivo. ResultsRMRP and ELAVL1 was upregulated in LPS-treated HK-2 cells, and RMRP or ELAVL1 overexpression inhibited cell viability and promoted cell apoptosis, inflammatory factor secretion and oxidative stress, and RMRP knockdown showed the opposite effects. ELAVL1 upregulated COX2 protein expression and overexpression of COX2 reversed the promoting effects of RMRP knockdown on cell viability, as well as the inhibitory effects on cell apoptosis, inflammatory factor secretion and oxidative stress. Mechanistic findings suggested that RMRP aggravates LPS induced cell injury by activating prostaglandin E (PGE)/janus kinase-2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling pathway. We observed that knockdown of RMRP expression significantly alleviated renal tissue apoptosis, inflammatory factor secretion, and oxidative stress with AKI mice. ConclusionsOur findings may provide a new reference for the treatment of AKI.

Bioactivity of dihydropyrimidinone derivatives as inhibitors of cyclooxygenase-2 (COX-2): an in silico approach.

Cyclooxygenase-2 (COX-2) is an enzyme involved in inflammation. The overexpression of COX-2 causes chronic inflammation, which can be prevented by COX-2 inhibitors. Generally, COX-2 inhibitors possess a carboxyl group and an aromatic ring in their molecular structure. These moieties are involved in the interaction with the active site of COX-2, thus playing a pivotal role in the inhibitory activity. Regarding the requisite molecular structure of COX-2 inhibitors, derivatives of dihydropyrimidinone (DHPM) are ideal candidates to be explored as COX-2 inhibitors, due to the ease of synthesis and their versatility to be transformed chemically. In this study, we prepared a novel small library consisting of 288 designed DHPM derivatives by varying the constituent components. The selection criteria of potential candidates for the COX-2 inhibitor of the data bank involve in silico studies via molecular docking investigations, prediction of ADMET and druglikeness, as well as molecular dynamics (MD) simulations. Molecular docking served as the initial step of selection, based on the comparison of grid score, docking pose, and interactions with those of lumiracoxib (LUR) as the original ligand of COX-2. The next criteria of selection were scores obtained from the ADMET and druglikeness by comparing the designed candidates with COX-2 inhibitors that were already marketed. Compound RDUE2 and SDT29 were the most potential candidates, which were further analyzed using the MD simulation. The results of the MD simulation indicated that RDUE2 and SDT29 interacted stably with amino acid residues on the active site of COX-2. The estimation of binding free energy indicated that SDT29 exhibited an inhibitory activity comparable to that of LUR, whereas RDUE2 showed a lower inhibitory activity than that of SDT29 and LUR.

Brucine suppresses proliferation and promotes apoptosis of human cholangiacarcinoma cells via the inhibition of COX2 expression.

Aims The aim of this study was to investigate the anti-tumor efficacy of brucine on intrahepatic cholangiocarcinoma (ICC). Methods ICC QBC939 cells were treated with brucine, cell viability, cell cycle and apoptosis were analyzed using CCK-8 and flow cytometry. The expression of COX-2 and apoptosis related proteins Casp3, Bax and Bcl-2 were detected by Western blot analysis. QBC939 cells were subcutaneously transplanted into nude mice and the mice were injected with brucine intraperitoneally. The expression of Ki67, COX-2 and apoptosis related proteins were detected by immunohistochemical staining and Western blot analysis. Results Brucine significantly inhibited the proliferation and cell cycle progression while promoted the apoptosis of QBC939 cells. The expression of the apoptotic proteins Casp3 and Bax was upregulated, while the expression of Bcl-2 and COX-2 was downregulated in QBC939 cells with brucine treatment. Moreover, the overexpression of COX-2 could antagonize the effects of brucine on QBC939 cells. In vivo, brucine inhibited subcutaneous tumor formation in nude mice, and the expression of Ki67, COX-2 and Bcl-2 decreased while the expression of Casp3 and Bax increased in tumor tissues from nude mice with brucine treatment. Conclusions Brucine can significantly inhibit the progression of cholangiocarcinoma in vitro and in vivo, and the mechanism may be related to the inhibition of COX-2 expression.