Curcumin inhibits proteasome activity in triple-negative breast cancer cells through regulating p300/miR-142–3p/PSMB5 axis

BackgroundCurcumin functions as a proteasome inhibitor. However, the molecular mechanisms behind this action need more detailed explanations.PurposeThis study aimed to investigate the inhibitory effect of curcumin on 20S proteasome activity and to elucidate its exact mechanism in triple-negative breast cancer (TNBC) MDA-MB-231 cells.MethodsProteasomal peptidase activities were assayed using synthetic fluorogenic peptide substrates. Knockdown or overexpression of microRNA (miRNA or miR) or protein was used to investigate its functional effect on downstream cellular processes. BrdU (5‑bromo‑2′-deoxyuridine) assay was performed to identify cell proliferation. Western blot and quantitative real-time PCR(qRT-PCR) were carried out to determine protein abundance and miRNA expression, respectively. Correlations between protein expressions, miRNA levels, and proteasome activities were analyzed in TNBC tissues. Xenograft tumor model was performed to observe the in vivo effect of curcumin on 20S proteasome activity.ResultsCurcumin significantly reduced PSMB5 protein levels, accompanied with a reduction in the chymotrypsin-like (CT-l) activity of proteasome 20S core. Loss of PSMB5 markedly inhibited the CT-l activity of 20S proteasome. Furthermore, curcumin treatment significantly elevated miR-142–3p expression. PSMB5 was a direct target of miR-142–3p and its protein levels were negatively regulated by miR-142–3p. Moreover, histone acetyltransferase p300 suppressed miR-142–3p expression. Overexpression of p300 mitigated the promotive effect of curcumin on miR-142–3p expression. The correlations among p300 abundances, miR-142–3p levels, PSMB5 expressions, and the CT-l activities of 20S proteasome were evidenced in TNBC tissues. In addition, loss of p300 and PSMB5 reduced cell proliferation. Inhibition of miR-142–3p significantly attenuated the inhibitory impact of curcumin on cell proliferation. These curcumin-induced changes on p300, miR-142–3p, PSMB5, and 20S proteasome activity were further confirmed in in vivo solid tumor model.ConclusionThese findings demonstrated that curcumin suppressed p300/miR-142–3p/PSMB5 axis leading to the inhibition of the CT-l activity of 20S proteasome. These results provide a novel and alternative explanation for the inhibitory effect of curcumin on proteasome activity and also raised potential therapeutic targets for TNBC treatment.     

LINC00461 promotes cell migration and invasion in breast cancer through miR-30a-5p/integrin β3 axis

Mounting evidence has demonstrated that long noncoding RNAs (lncRNAs) are dysregulated and implicated in the occurrence and development of a wide range of human malignancies. LINC00461, a novel cancer-related lncRNA, has been reported to be highly expressed and serve as oncogene in glioma; however, its biological role in breast cancer (BC) remains obscure. This study aimed to explore the role of LINC00461 in BC and elucidate the potential molecular mechanisms involved. In the current study, LINC00461 was found to be significantly upregulated in both BC tissues and cell lines. Besides, we found that high LINC00461 expression was associated with TNM stage and differentiation. Furthermore, functional studies demonstrated that LINC00461 expedited BC cell migration and invasion. Notably, LINC00461 was observed to enhance the expression of vimentin and zinc-finger E-box binding homeobox factor 1, suppress the expression of E-cadherin, and promote the activation of extracellular signal-regulated kinase and AKT signaling pathways. Mechanical investigations revealed that LINC00461 positively modulated integrin β3 (ITGB3) expression as miR-30a-5p sponge in BC cells. Taken together, LINC00461 exerts an oncogenic role in BC through miR-30a-5p/ITGB3 axis. Our data indicate that LINC00461 may be used to be a novel candidate therapeutic target and a valuable diagnostic biomarker for BC.     

Downregulated long noncoding RNA LINC00313 inhibits the epithelial–mesenchymal transition,invasion, and migration of thyroid cancer cells through inhibiting the methylation of ALX4

Thyroid cancer represents one of the prevalent endocrine cancer with relatively high incidence rate around the world, accompanied by unchanged fatality rate. We probe into the specific role of LINC00313 in mediation of cellular processes of thyroid cancer including proliferation, migration, and invasion through the methylation of aristaless-like homeobox 4 (ALX4). Thyroid cancer-related long noncoding RNAs (lncRNAs) and genes were analyzed by microarray-based analysis. The antitumor effect of LINC00313 was examined with the gain- and loss-of-function experiments. In addition, the binding of LINC00313 and the promoter region of ALX4, and the interaction of LINC00313 with methylation-related proteins were detected. Later, xenograft tumors in nude mice were induced expecting to dig out the modulatory function of LINC00313 in tumor growth of thyroid carcinoma. The microarray-based analysis manifested that LINC00313 was overexpressed, whereas ALX4 was downregulated in thyroid cancer, the results of which were also verified in thyroid cancer tissues. Besides, our results demonstrated that LINC00313 bound to the ALX4 promoter region, and LINC00313 recruited DNMT1 and DNMT3B proteins to promote the methylation of ALX4 promoter region, thus suppressing the ALX4 expression. Finally, the downregulation of LINC00313 and upregulation of ALX4 repressed the AKT/mTOR signaling axis, thus inhibiting proliferative, migratory, invasive abilities as well as epithelial-to-mesenchymal transition (EMT) of thyroid cancer cells. Collectively, downregulated LINC00313 suppresses cell proliferation, migration, as well as invasion of thyroid cancer by inhibiting the methylation of ALX4 and increasing its expression by inactivation of the AKT/mTOR signaling pathway.     

LncRNA GABPB1‑IT1 inhibits the tumorigenesis of renal cancer via the miR-21/PTEN axis

Long noncoding RNA (lncRNA) (GABPB1‑IT1) has been reported to be downregulated in lung cancer, while its expression and function in other cancers are unknown. In this study, the expression levels of GABPB1‑IT1 in tissue samples from 62 ccRCC patients were measured by performing RT-qPCR. Potential base pairing formed between GABPB1‑IT1 and miR-21 was explored using the online program IntaRNA 2.0 and further confirmed by Dual-luciferase activity assay and RNA pulldown assay. The role of GABPB1‑IT1 and miR-21 in regulating the expression of PTEN was evaluated by RT-qPCR and Western blot. The role of GABPB1‑IT1, miR-21, and PTEN in regulating the proliferation of Caki-2 cells was explored by CCK-8 assay. It was observed that GABPB1‑IT1 was downregulated in ccRCC and predicted poor survival. GABPB1‑IT1 directly interacted with miR-21, while it did not regulate the expression of each other. Moreover, upregulation of PTEN, which is a target of miR-21, was observed in ccRCC cells with overexpression of GABPB1‑IT1. Overexpression of GABPB1‑IT1 and PTEN decreased the proliferation rates of ccRCC cells. In addition, overexpression of GABPB1‑IT1 reduced the enhancing effects of miR-21 on cell proliferation. Therefore, GABPB1‑IT1 may upregulate PTEN by sponging miR-21 in ccRCC to inhibit cancer cell proliferation. Our study characterized a novel GABPB1‑IT1/miR-21/PTEN axis in ccRCC.     

Down-regulated LINC00115 inhibits prostate cancer cell proliferation and invasion via targeting miR-212-5p/FZD5/Wnt/β-catenin axis

Prostate cancer is the second most frequent malignancy in men worldwide, and its incidence is increasing. Therefore, it is urgently required to clarify the underlying mechanisms of prostate cancer. Although the long non-coding RNA LINC00115 was identified as an oncogene in several cancers, the expression and function of LINC00115 in prostate cancer have not been explored. Our results showed that LINC00115 was significantly up-regulated in prostate cancer tissues, which was significantly associated with a poor prognosis for prostate cancer patients. Functional studies showed that knockdown LINC00115 inhibited cell proliferation and invasion. In addition, LINC00115 served as a competing endogenous RNA (ceRNA) through sponging miR-212-5p to release Frizzled Family Receptor 5 (FZD5) expression. The expression of miR-212-5p was noticeably low in tumour tissues, and FZD5 expression level was down-regulated with the knockdown of LINC00115. Knockdown LINC00115 inhibited the Wnt/β‑catenin signalling pathway by inhibiting the expression of FZD5. Rescue experiments further showed that LINC00115 inhibits prostate cancer cell proliferation and invasion via targeting miR-212-5p/ FZD5/ Wnt/β-catenin axis. The present study provided clues that LINC00115 may be a promising novel therapeutic target for prostate cancer patients.     

MiR-145 inhibits the migration and invasion of papillary thyroid carcinoma cells through NF-κB pathway regulation

Papillary thyroid carcinoma (PTC) is the most prevalent cancer in the endocrine system, and the number of patients diagnosed with PTC has been increasing rapidly in recent years. Previous studies have reported that miR-145 plays an important role in many kinds of cancers, but its function in PTC remains unclear. In this study, we found that compared to paracancerous tissues, the level of miR-145 expression was significantly downregulated in PTC tissues. When miR-145 is overexpressed, migration and invasion of PTC cells were suppressed in vitro. In addition, we found that miR-145 downregulated the nuclear factor-κB (NF-κB) pathway in PTC cells. Taken together, our data suggest that miR-145 functions as a tumor suppressor in PTC with the suppressive effect related to downregulation of the NF-κB pathway.     

Circ_0015756 promotes ovarian cancer progression via the miR-145–5p/PSAT1 axis

Circular RNA (circRNA) have been shown to exert vital functions in the pathological progressions of ovarian cancer (OC). Herein, this study aimed to investigate the role and mechanisms of circ_0015756 in OC progression. Levels of circ_0015756, microRNA (miR)? 145–5p and phosphoserine aminotransferase 1 (PSAT1) were detected using quantitative real-time polymerase chain reaction, Western blot or immunohistochemistry assays. Cell proliferation, apoptosis, migration and invasion were determined using cell counting kit-8, 5-Ethynyl-2′-Deoxyuridine (Edu) incorporation, flow cytometry, transwell and Western blot assays. The binding interaction between miR-145–5p and circ_0015756 or PSAT1 was confirmed by bioinformatics prediction and dual-luciferase reporter assay. Tumor formation assay in nude mice was performed to determine the tumor growth in vivo. Circ_0015756 was highly expressed in OC tissues and cells. Knockdown of circ_0015756 suppressed cancer cell growth, migration and invasion in vitro, as well as impeded tumor growth in vivo. In a mechanical study, circ_0015756 directly bound to miR-145–5p, and inhibition of miR-145–5p reversed the effects of circ_0015756 knockdown on OC cells. Moreover, miR-145–5p directly targeted PSAT1, and miR-145–5p weakened OC cell growth, migration and invasion via targeting PSAT1. Importantly, further studies confirmed that circ_0015756 could indirectly regulate PSAT1 expression via sponging miR-145–5p. In all, circ_0015756 accelerated OC tumorigenesis through regulating miR-145–5p/PSAT1 axis, providing a new therapeutic target for OC.     

β-Elemene inhibits the metastasis of multidrug-resistant gastric cancer cells through miR-1323/Cbl-b/EGFR pathway

Backgroundβ-Elemene is a natural agent extracted from the traditional Chinese herbal medicine Curcuma wenyujin that is a promising novel plant-derived drug with broad-spectrum anticancer activity. Our previous study identified an enhanced capacity for metastasis in multidrug resistant (MDR) gastric cancer and breast cancer cells. However, the anti-metastatic effects of β-Elemene on MDR cancer cells remain unknown.PurposeIn this study, we posit the hypothesis that β-elemene possesses antimetastatic effects on MDR cancer cells.MethodsCell viability assay was used to assess the resistance of SGC7901/ADR cells and the cytotoxic effects of β-Elemene. Wound healing, transwell assay and lung metastatic mice model were used to the anti-metastasis effects of β-Elemene. MicroRNA microarray analysis was used to explore potential regulated miRNAs. Luciferase reporter assay was used to identify the direct target. Human MMP antibody array, western blot, immunoprecipitation, qRT-PCR analyses and immunohistochemistry were conducted to investigate the underlying anti-metastasis mechanism of β-Elemene.ResultsIn this study, we found that β-Elemene significantly inhibited the metastatic capacity of MDR gastric cells in vivo and in vitro. Mechanistically, we found that β-Elemene regulated MMP-2/9 expression and reversed epithelial-mesenchymal transition. Further studies showed that β-Elemene upregulated Cbl-b expression, resulting in inhibition of the EGFR-ERK/AKT pathways, which regulate MMP-2/9. Additionally, we confirmed that β-Elemene upregulated Cbl-b by inhibiting miR-1323 expression. Finally, we found that numbers of metastatic tumor nodules were significantly decreased in the lungs of nude mice after β-Elemene treatment.ConclusionOur results suggested that β-Elemene inhibits the metastasis of MDR gastric cancer cells by modulating the miR-1323/Cbl-b/EGFR signaling axis.     

Silencing of lncRNA ZFAS1 inhibits malignancies by blocking Wnt/β-catenin signaling in gastric cancer cells

Gastric cancer is a common malignancy with high mortality. Long noncoding RNA (lncRNA) zinc finger antisense (ZFAS)1 is upregulated in gastric cancer specimens compared with the para-carcinoma tissues. The silencing of ZFAS1 inhibited the growth, proliferation, cell cycle progress, migration, invasion and epithelial-mesenchymal transition (EMT), and enhanced the sensitivity to cis-platinum or paclitaxel in SGC7901 cells, as evidenced by the expression changes of proliferating cell nuclear antigen, Cyclin D1, Cyclin E, Cyclin B1, E-cadherin, N-cadherin, vimentin, matrix metalloproteinase (MMP)-2 and MMP-14. The ZFAS1 also activated the Wnt/β-catenin signaling. Subsequently, the ZFAS1 knockdown-induced the inhibition of migration, invasion, EMT and resistance to chemotherapeutic reagens was reversed by the overexpression of β-catenin. In summary, the silencing of ZFAS1 inhibited the growth, proliferation, cell cycle progress, migration, invasion, EMT and chemotherapeutic tolerance by blocking the Wnt/β-catenin signaling in gastric cancer cells.     

microRNA-448 inhibits the progression of non-small–cell lung cancer through regulating IRS2

Recently, microRNA-448 (miR-448) has been reported to be a tumor-associated miRNA in many human cancers. In this study, we investigated the function of miR-448 in non-small–cell lung cancer (NSCLC) progression and confirmed the relationship between miR-448 and insulin receptor substrates 2 (IRS2). First, downregulation of miR-448 and upregulation of IRS2 were detected in NSCLC using the quantitative real-time polymerase chain reaction (qRT-PCR) assay. Furthermore, the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assay showed that miR-448 inhibited cell viability in NSCLC. Transwell and Western blot assays indicated that the upregulation of miR-448 inhibited cell metastasis and epithelial-to-mesenchymal transition (EMT) in NSCLC. And it was found that overexpression of miR-448 reduced the adhesion of A549 cells to HUVEC cells using the adhesion assay. Furthermore, the dual luciferase assay indicated that miR-448 directly targeted IRS2 in NSCLC. In addition, it was found that IRS2 silencing had an inhibitory effect on the progression of NSCLC, and the upregulation of IRS2 partially impaired the inhibitory effect of miR-448 in NSCLC. Briefly, overexpression of miR-448 inhibited cell proliferation, metastasis, and EMT by suppressing IRS2 expression in NSCLC.     

Long non-coding RNA LINC01347 suppresses trophoblast cell migration,invasion and EMT by regulating miR-101–3p/PTEN/AKT axis

Recurrent miscarriage (RM) is one of the common complications of pregnancy, which is closely related to gene mutation. The profiling of non-coding RNAs showed that the expression level of long non-coding RNA LINC01347 (LINC01347) in the serum of patients with recurrent abortion was significantly increased, which could serve as a potential marker for early diagnosis. However, the biological functions of LINC01347 in the miscarriage remain to be elucidated. In this study, LINC01347 expression levels in HTR-8/SVneo cells and placenta samples were measured by RT-qPCR. The migration ability of HTR-8/SVneo cells was detected by wound-healing assay. Western blotting (WB) assay was conducted to measure E-cadherin, Vimentin, N-cadherin, PTEN, phospho-AKT(S473), phospho-AKT(T308) and AKT levels. Dual luciferase reporter assay and RNA pull-down analysis were performed to validate the molecular interactions. The results showed an upregulation of LINC01347 in the placenta samples of RM patients and HTR-8/SVneo cells. LINC01347 overexpression impaired the invasion and migration of trophoblast cells, while LINC01347 silencing promoted cell migration and invasion. LINC01347 level was also negatively correlated with the changes of epithelial-mesenchymal transition (EMT) markers in trophoblasts. We further demonstrated that miR-101–3p/PTEN/AKT axis played an important role in mediating the biological roles of LINC01347 in the invasion and migration of trophoblasts. In conclusion, our results revealed that LINC01347 suppresses the migratory ability and regulates the EMT processes in trophoblasts by regulating miR-101–3p/PTEN/AKT axis, suggesting that targeting LINC01347 may serve as a strategy to ameliorate RM.     

LncRNA PVT1 promotes the progression of ovarian cancer by activating TGF-β pathway via miR-148a-3p/AGO1 axis

Ovarian cancer is a lethal gynaecologic malignancy with poor diagnosis and prognosis. The long non-coding RNA plasmacytoma variant translocation1 (PVT1) and argonaute 1 (AGO1) are associated with carcinogenesis and chemoresistance; however, the relationship between PVT1 and AGO1 and the downstream mechanisms in ovarian cancer remains poorly known. PVT1 and AGO1 expression was assessed through RT-qPCR and Western blotting in both human tissues and cell lines. The viability and proliferation of ovarian cancer cells were determined by CCK-8 assay and TUNEL assay in vitro and immunohistochemistry in vivo. Cell invasion and migration were investigated through transwell and wound-healing assays. The roles and mechanisms of AGO1 on cell functions were further probed via gain- and loss-of-function analysis. We reveal that PVT1 expression was significantly increased in ovarian cancer tissues which is associated with advanced FIGO stage, lymph-node metastasis, poor survival rate, and high expression of AGO1. PVT1 or AGO1 knockdown significantly reduced the cell viability and increased the cell apoptosis and inhibited ovarian tumour growth and proliferation. Furthermore, we discovered that PVT1 up-regulated the expression of AGO1 and thus regulated the transforming growth factor-β (TGF-β) pathway to promote ovarian cancer progression through sponging miR-148a-3p. Additionally, the activation of ERK1/2, smad2 and smad4 is observed to be related to the PVT1/miR-148a-3p/AGO1/TGF-β pathway-induced cascades. Taken together, the present study reveals that PVT1/miR-148a/AGO1 axis plays an important role in the progression of ovarian cancer and emphasize the potential as a target of value for ovarian cancer therapy.     

Melatonin inhibits Müller cell activation and pro-inflammatory cytokine production via upregulating the MEG3/miR-204/Sirt1 axis in experimental diabetic retinopathy

Diabetic retinopathy (DR) is the most common ocular complication caused by diabetes mellitus and is the main cause of visual impairment in working-age people. Reactive gliosis and pro-inflammatory cytokine production by Müller cells contribute to the progression of DR. Melatonin is a strong anti-inflammatory hormone, mediating the cytoprotective effect of a variety of retinal cells against hyperglycemia. In this study, melatonin inhibited the gliosis activation and inflammatory cytokine production of Müller cells in both in vitro and in vivo models of DR. The melatonin membrane blocker, Luzindole, invalidated the melatonin-mediated protective effect on Müller cells. Furthermore, melatonin inhibited Müller cell activation and pro-inflammatory cytokine production by upregulating the long noncoding RNA maternally expressed gene 3/miR-204/sirtuin 1 axis. In conclusion, our study suggested that melatonin treatment could be a novel therapeutic strategy for DR.     

LINC00261 suppresses human colon cancer progression via sponging miR-324-3p and inactivating the Wnt/β-catenin pathway

Growing evidence indicates long noncoding RNAs (lncRNAs) are significant regulators in the progression of various malignant tumors including colon cancer. Dysregulation of lncRNA LINC00261 has been identified in many cancers. Investigations on LINC00261 function have revealed that LINC00261 could act as a crucial tumor suppressor in various cancers. But, the biological involvement of LINC00261 in colon cancer is still barely known. Here, we found LINC00261 was reduced in colon cancer cells. Meanwhile, overexpressed LINC00261 repressed colon cancer cell viability and proliferation capacity. In addition, colony cancer cell colony formation was inhibited and apoptosis was enhanced by upregulation of LINC00261. Also, colon cancer cell migration and invasion both were restrained by LINC00261. miR-324-3p can exert important functions in several carcinomas, but its role in colon cancer is uninvestigated. In the current study, miR-324-3p was examined and miR-324-3p was greatly increased in colon cancer cells. Moreover, the association between miR-324-3p and LINC00261 was confirmed via performing RNA immunoprecipitation and RNA-pull-down experiments. In cancer biology, aberrant modulation of the Wnt signaling pathway remains a prevalent theme. Overexpression of LINC00261 obviously impaired colon cancer progression via inactivating the Wnt pathway. Furthermore, in the xenograft model assay, an increase of LINC00261 could suppress colon tumor growth via sponging miR-324-3p and inactivating the Wnt pathway. Overall, our results showed that LINC00261 repressed colon cancer progression via regulating miR-324-3p and the Wnt pathway. LINC00261 could be established as a novel therapeutic target for colon cancer.     

Knockdown of lncRNA ZFAS1-suppressed non–small cell lung cancer progression via targeting the miR-150-5p/HMGA2 signaling

Non–small cell lung cancer (NSCLC) is the main type of lung malignancy. Early diagnosis and treatments for NSCLC are far from satisfactory due to the limited knowledge of the molecular mechanisms regarding NSCLC progression. Long noncoding RNA (lncRNA) ZNFX1 antisense RNA1 (ZFAS1) has been implicated for its functional role in the progression of malignant tumors. This study aimed to determine the ZFAS1 expression from lung cancer clinical samples and to explore the molecular mechanisms underlying ZFAS1-modulated NSCLC progression. Experimental assays revealed that clinical samples and cell lines of lung malignant tumors showed an upregulation of ZFSA1. ZFAS1 expression was markedly upregulated in the lung tissues from patients with advanced stage of this malignancy. The loss-of-function assays showed that knockdown of ZFAS1-suppressed NSCLC cell proliferative, as well as invasive potentials, increased NSCLC cell apoptotic rates in vitro and also attenuated tumor growth of NSCLC cells in the nude mice. Further experimental evidence showed that ZFAS1 inversely affected miR-150-5p expression and positively affected high-mobility group AT-hook 2 (HMGA2) expression in NSCLC cell lines. MiR-150-5p inhibition or HMGA2 overexpression counteracted the effects of ZFAS1 knockdown on NSCLC cell proliferative, invasive potentials and apoptotic rates. In light of examining the clinical lung cancer samples, miR-150-5p expression was downregulated and the HMGA2 expression was highly expressed in the lung cancer tissues compared with normal ones; the ZFAS1 expression showed a negative correlation with miR-150-5p expression but a positive correlation with HMGA2 expression in lung cancer tissues. To summarize, we, for the first time, demonstrated the inhibitory effects of ZFAS1 knockdown on NSCLC cell progression, and the results from mechanistic studies indicated that ZFAS1-mediated NSCLC progression cells via targeting miR-150-5p/HMGA2 signaling.     

Silencing of H4R inhibits the production of IL-1β through SAPK/JNK signaling in human mast cells

Context: Mast cell (MC) activation through H4R releases various inflammatory mediators which are associated with allergic asthma.

Objectives: To investigate the siRNA-mediated gene silencing effect of H4R on human mast cells (HMCs) functions and the activation of stress-activated protein kinases (SAPK)/jun amino-terminal kinases (JNK) signaling pathways for the release of ineterleukin-1β (IL-1β) in HMCs.

Materials and methods: H4R expression was analyzed by RT-PCR and western blotting in human mast cell line-1 (HMC-1) cells and H4RsiRNA transfected cells. The effect of H4RsiRNA and H4R-antagonist on H4R mediated MC functions such as intracellular Ca²⁺ release, degranulation, IL-6 and IL-1β release, and the activation SAPK/JNK signaling pathways were studied. HMC-1 cells were stimulated with 10?μM of histamine (His) and 4-methylhistamine (4-MH) and pretreated individually with H4R-antagonist JNJ7777120 (JNJ), histamine H1 receptor (H1R)-antagonist mepyramine, and signaling molecule inhibitors SP600125 (SP) and Bay117082.

Results: We found that the HMC-1 cells expressed H4R and H4RsiRNA treatment down regulated the H4R expression in HMC-1 cells. Both His and 4-MH induced the intracellular Ca²⁺ release and degranulation whereas; H4R siRNA and JNJ inhibited the effect. Furthermore, the activation of H4R caused the phosphorylation of SAPK/JNK pathways. H4R gene silencing and pretreatment with SP and JNJ decreased His and 4-MH induced phosphorylation of SAPK/JNK. We found that the activation of H4R caused the release of IL-1β (124.22?pg/ml) and IL-6 (122.50?pg/ml) on HMC-1 cells. Whereas, SAPK/JNK inhibitor (68.36?pg/ml) inhibited the H4R mediated IL-1β release.

Conclusions: Taken together, the silencing of H4R inhibited the H4R mediated MC functions and SAPK/JNK phosphorylation. Furthermore, the H4R activation utilized SAPK/JNK signaling pathway for IL-1β release in HMC-1 cells.