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Cervical cancer (CC) remains one of the leading malignancies afflicting females worldwide, with its aetiology associated with long‐term papillomavirus infection. Recent studies have shifted their focus and research attention to the relationship between long non‐coding RNAs (lncRNAs) and CC therapeutic. Thus, the aim of the current study was to investigate the underlying mechanism of lncRNA LINC01305 on the cell invasion, migration and epithelial‐mesenchymal transition (EMT) of CC cells via modulation of the PI3K/Akt signalling pathway by targeting tenascin‐X B (TNXB). The expressions of LINC01305, TNXB, MMP2, MMP9, E‐cadherin, vimentin, PI3K, Akt, p‐PI3K, p‐Akt and TNXB were detected in this study. After which, the cell invasion and migration abilities of the CC cells were determined respectively. Bioinformatics and the application of a dual luciferase reporter gene assay provided verification indicating that TNXB is the target gene of lncRNA LINC01305. Reverse transcription quantitative polymerase chain reaction (RT‐qPCR) and western blot analysis methods revealed that the expressions of MMP2, MMP9, vimentin, PI3K, Akt, p‐PI3K and p‐Akt were decreased following the down‐regulation of LncRNA LINC01305 or overexpression of TNXB. LncRNA LINC01305 silencing or TNXB overexpression was noted to decrease the migration and invasion of SiHa cells. Taken together, the key findings of the current study present evidence suggesting that lncRNA LINC01305 silencing suppresses EMT, invasion and migration via repressing the PI3K/Akt signalling pathway by means of targeting TNXB in CC cells, which ultimately provides novel insight and identification of potential therapeutic targets for CC. [ABSTRACT FROM AUTHOR]

An efficient copper-catalyzed reactions of imidazole, indole, and triazole with aryl or heteroaryl halides using cyclen derivatives as efficient organic base and ligand at moderate temperature have been investigated. The proceed smoothly with good to excellent yields. [ABSTRACT FROM AUTHOR]

α, β-Unsaturated aldehydes reacted with diimide (diazene) in the presence of optically active ammonium salt 1 as a catalyst to give the corresponding saturated aldehydes in excellent yields and up to 98 : 2 er. Attractive features of the asymmetric transfer hydrogenation are its high yields, and chemo-, and enantioselectivities. [ABSTRACT FROM AUTHOR]

Cervical cancer (CC) remains a distinct public health stumbling block worldwide. Increasing evidence has highlighted long non-coding RNAs (lncRNAs) as tumor-associated biological molecules. In this study, by means of altering the expression of lncRNA RP1-93H18.6 in CC cells, its ability to influence the biological activities of CC cells was evaluated. Differentially expressed lncRNAs were initially screened from the GEO database. A series of RP1-93H18.6 vectors, small interfering RNA (siRNA) against RP1-93H18.6, and LY294002 (an inhibitor for the phosphatidylinositol 3-kinase [PI3K]/Akt [serine/threonine kinase] axis) were introduced in a respective manner to treat the HeLa cells in order to analyze their effects on cellular activities in vitro. Nude mice with xenograft tumors were utilized in order to assess CC tumor growth and metastasis in vivo. lncRNA RP1-93H18.6 was highly expressed in CC, which could activate the P13K/Akt axis. RP1-93H18.6 vectors exposure increased cell viability, adhesion, migration, and invasion, which resulted in more cells arrested at the S stage and reduced apoptosis, while acting to promote tumor growth and metastasis. The siRNA against RP1-93H18.6 or LY294002 exposure was observed to attenuate the effects induced by RP1-93H18.6 vectors. This study suggests that suppression of lncRNA RP1-93H18.6 exerts potent inhibitory effects on the development and progression of CC via blockade of the PI3K/Akt axis., (Copyright © 2019. Published by Elsevier Inc.)

Objective: To study the chemical constituents in the bark of Taxus chinensis var. mairei collected from southeast of China., Methods: Chemical constituents were isolated and purified by column chromatography, Prep-TLC, and preparative HPLC. The structures were identified on the basis of 1D-and 2D-NMR spectral analysis., Results: Twelve taxane diterpenoids were isolated from the bark of Taxus chinensis var. mairei grown in southeast of China. They were identified as: taxagifine (1), decinnamoyltaxagifine (2), 19-debenzoyl-19-acetyltaxinine M(3), 9-dihydro-13-acetyl-baccatin III (4), 7, 9-dideacetylbaccatin IV (5), 1,3-dihydro-taxinine (6), taxumairol C (7), taxezopidine J (8), 7-xylosyl-10-deacetyl-taxol A (9),10-deacetyltaxol (10), taxicin II (11), and 2alpha, 7beta, 10beta-triacetoxy-5alpha, 13alpha-dihydroxy-2 (3 --> 20) abeotaxa-4 (20), 11-dien-9-one (12)., Conclusion: Compounds 1, 2, 4 - 6, 8, 9, 11 and 12 are obtained from this plant for the first time. Compound 7 is obtained from the bark of Taxus chinensis var. mairei for the first time.

Objective: To investigate the influence of pertussis toxin (PTX) on G protein-coupled estrogen receptor (GPER)-mediated activation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling activated by 17β-estradiol (17β-E2) in endometrial carcinoma cells., Methods: Expressions of GPER protein were detected by immunohistochemical SP method in Ishikawa and HEC-1A cells. Changes of levels of GPER, ERα and ERβ protein and the activation of Akt protein were observed by western blot in the two cells after they were treated by PTX for 30 minutes at different concentrations (0, 0.1, 0.5, 1.0 µg/ml), and then co-stimulated with with 1×10(-6) mol/L 17β-E2 respectively at different time (Ishikawa 30 minutes, HEC-1A 15 minutes)., Results: (1) Immunohistochemical SP method showed that GPER was positive stained in cell cytoplasm of Ishikawa and HEC-1A cell. (2) After co-treated with PTX at different concentrations (0, 0.1, 0.5, 1.0 µg/ml) and 10(-6) mol/L 17β-E2, in Ishikawa cell, the ratio of p-Akt/Akt was 0.74 ± 0.54, 0.34 ± 0.06, 0.18 ± 0.03, 0.07 ± 0.15, the gray values of GPER was 0.872 ± 0.490, 0.395 ± 0.054, 0.145 ± 0.014, 0.034 ± 0.008, and with increasing concentration of PTX, the ratio of p-Akt/Akt and the expression of GPER decreased gradually (P < 0.05), which was most obviously when the concentration was 1.0 µg/ml (F = 63.729, P = 0.0001; F = 160.284, P = 0.0001); ERα and ERβ protein had no significant change among different groups (P > 0.05). In HEC-1A cell, the ratio of p-Akt/Akt was 0.73 ± 0.09, 0.26 ± 0.14, 0.11 ± 0.03, 0, the Gray values of GPER is 0.927 ± 0.134, 0.485 ± 0.022, 0.194 ± 0.004, 0, and with increasing concentration of PTX, the ratio of p-Akt/Akt and the expression of GPER decreased gradually (P < 0.05), which were also completely inhibited when the concentration was 1 µg/ml (F = 1039.321, P = 0.0001; F = 109.646, P = 0.0001), ERα protein had no significant differences (P > 0.05) among different groups. ERβ was negatively expressed., Conclusion: The results proposed that the activation of PI3K/Akt signaling in Ishikawa and HEC-1A cells could be inhibited after blocking the role of GPER by PTX.

Objectives: To investigate the effects of plasma from the patients with preeclampsia on proliferation and apoptosis of human umbilical vein endothelial cells (HUVEC), and to explore the relationship between cell damage and lysophosphatidic acid (LPA) receptors., Methods: Sixty patients with preeclampsia were recruited from October 2011 to June 2012 in the First Affiliated Hospital of Zhengzhou University. Among them, thirty cases were defined as the mild preeclampsia group and thirty cases were defined as the severe preeclampsia group. The other thirty healthy pregnant women were recruited in the healthy pregnant women group. The levels of plasma LPA in the three groups were measured. The HUVEC were cultured in vitro with plasma from the three groups, and a blank control group was set up as well. Proliferation and apoptosis of HUVEC were measured by MTT assay and flow cytometry. Immunohistochemistry of biotin streptomyces protein peroxidase (SP) method was used to measure the protein expression level of Edg 2, 4, 7., Results: (1) The plasma LPA levels in the healthy pregnant woman group, mild preeclampsia group and severe preeclampsia group were (3.38 ± 2.08) µmol/L, (6.12 ± 0.22) µmol/L, (9.10 ± 0.17) µmol/L, respectively. The plasma levels of LPA in patients with preeclampsia were significantly higher than that in the healthy pregnant women (P < 0.01). (2) The proliferation rate of HUVEC in the mild and severe preeclampsia groups [(65.2 ± 2.7)% and (51.9 ± 2.8)%] were significantly lower than that in the healthy pregnant women group and the control group [(84.3 ± 3.1)% and (100.0 ± 0.0)%, P < 0.01]. (3) The early apoptosis rate, middle-late apoptosis rate and total apoptosis rate of HUVEC in the mild and severe preeclampsia groups [total apoptosis rate were (30.4 ± 2.0)% and (43.4 ± 2.5)%] were significantly higher than those in the healthy pregnant women group and the control group [total apoptosis rate were (18.6 ± 1.6)% and (8.0 ± 1.5)%, P < 0.01]. (4) The expression positive rates of Edg 2, 4, 7 proteins in the four groups were as following: mild preeclampsia group 83%, 80% and 73%; severe preeclampsia group 97%, 93% and 90%; healthy pregnant women group 40%, 40% and 37%, and the control group 10%, 10% and 7% respectively. The positive rates of HUVEC in the mild and severe preeclampsia groups were significantly higher than those in the healthy pregnant women group and the control group (P < 0.01)., Conclusions: The plasma of patients with preeclampsia could inhibit proliferation and promote apoptosis of HUVEC, and induce the expression of Edg 2, 4, 7 proteins. It suggested that the increase of lysophosphatidic acid in plasma could be one of the reasons of endothelial cell damage in patients with preeclampsia.

Objective: To investigate the expression of G protein-coupled ER (GPER) and ER in the activation of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) induced by 17β-estradiol (17β-E(2))in endometrial carcinoma cells, Ishikawa and HEC-1A., Methods: Expressions of GPER, ERα and ERβ protein in Ishikawa and HEC-1A cells were detected by immunohistochemical SP method. Levels of GPER, ERα and ERβ were examined by western blot in Ishikawa and HEC-1A cells after treated with 1×10(-6) mol/L 17β-E(2) at different time (0, 15, 30, 60, 120 minutes)., Results: GPER was positive expressed in Ishikawa and HEC-1A cells. ERα and ERβ were both positive expressed in Ishikawa cells. While, ERα was weakly expressed and ERβ was almost negatively expressed in HEC-1A cells. Western blot analysis showed that 1×10(-6) mol/L 17β-E(2) treatment, the Ishikawa and HEC-1A cells GPER protein level for 15 minutes markedly increased (P < 0.05), which Ishikawa 30 minutes, when cells reached the highest level (0.192 ± 0.004), HEC-1A cells for 15 minutes and reached the highest level (0.184 ± 0.006); Ishikawa and HEC-1A cells, Akt, activation of 15 minutes from the treatment start was significantly increased (P < 0.05), which Ishikawa cells for 30 minutes and reached the highest level (0.666 ± 0.021), HEC-1A cells for 15 minutes and reached maximum (0.788 ± 0.035); Ishikawa and HEC-1A cells, ERα and ERβ protein expression did not change significantly (P > 0.05)., Conclusion: GPER likely involved in non-nuclear activation of PI3K/Akt signaling pathways in endometrial carcinoma cells, Ishikawa and HEC-1A.

Objective: To investigate the effects of signal pathway inhibitors PD98059 and LY294002 on cell proliferation, apoptosis, expressions of phosphorylated extracellular signal-regulared kinase (p-ERK) and phosphorylated protein kinase B (p-Akt) in endometrial carcinoma xenografts., Methods: Human endometrial carcinoma Ishikawa cells were cultured in vitro. The effects of PD98059 and LY294002 on proliferation, apoptosis, and cell cycle distribution of endometrial cancer cells were detected by monotetrazolium (MTT) assay and fluorescence-activated cell sorting technique. The models of xenografted tumor were established by the subcutaneous inoculation in 24 nude mice, and then they were randomly divided into 4 groups (n = 6), normal saline group, PD98059 group (PD group), LY294002 group (LY group) or PD98059 + LY294002 group (PD + LY group) by intraperitoneal injections, respectively. The anti-tumor efficacy was evaluated by measuring tumor volume and tumor growth status. The histopathological change of tumor specimens was observed using HE staining and terminal deoxynucleotidyl transferase-mediated dUTP-digoxigen in nick and labeling method (TUNEL) testing and the expression levels of p-ERK and p-Akt were detected by immunohistochemistry method., Results: (1) The proliferation of Ishikawa cells were suppressed after treated by PD98059 and(or) Y294002, in which A(570) values of cells decreased showing both time-dependent and concentration-dependent manner (LY294002: F(group) = 9.801, P = 0.002; F(time) = 10.398, P = 0.001. PD98059: F(group) = 8.213, P = 0.015; F(time) = 6.839, P = 0.036). Cell cycle distribution analysis revealed that percentage of Ishikawa cells at G(0)/G(1) phase (F(time) = 35.049, P = 0.004; F(group) = 32.024, P < 0.01) increased and percentage of S phase cells (F(time) = 7.789, P = 0.049; F(group) = 30.132, P < 0.01) decreased significantly. The percentage of apoptotic cells increased significantly among PD group, LY group and PD + LY group, in which there were significant difference [(63.3 ± 0.5)% vs (30.7 ± 20.1)% vs (40.8 ± 1.3)%; F = 621.059, P < 0.01]. (2) Compared with the control group, the increasing of transplanting tumor volume in the treated groups were obviously (F = 23.545, P < 0.01), and the inhibited rate of the tumor was higher in PD + LY group than that in PD group or LY group [(68 ± 9)% vs (32 ± 16)% or (38 ± 17)%; F = 10.283, P < 0.05]. (3) HE staining shown that there were different degrees of necrosis for endometrial carcinoma cell in different groups. The apoptosis of tumor cells were significantly increased in treated groups by TUNEL testing [(13.7 ± 1.5)%, (14.1 ± 1.2)%, (29.0 ± 1.8)%; F = 320.344, P < 0.01]. Immunohistochemistry results demonstrated that the expressions of p-ERK and p-Akt in treated groups were lower than that in control group, of which LY + PD group was the lowest one., Conclusion: The signal pathway inhibitors PD98059 and LY294002 could inhibit the growth of human endometrial carcinoma in vivo and in vitro, in which may induce cell apoptosis.

AKT plays an important role in malignant behavior of tumors. The purpose of the present study was to determine the expression of phosphorylated AKT (P-AKT) and nuclear factor-kappaB (NF-kappaB) p65 and their association with clinicopathological parameters and prognosis in epithelial ovarian tumor. On immunohistochemistry 115 samples of ovarian tissue that included 68 specimens of epithelial ovarian cancer, 12 of borderline tumor, 24 of epithelial benign tumor and 11 of normal ovary, were evaluated. Sixty-three patients with ovarian cancer were followed up from 7 to 68 months. The positive expression rate of P-AKT and NF-kappaB p65 were higher in epithelial ovarian cancer than in normal ovarian tissue (P<0.01). Elevated P-AKT or NF-kappaB p65 expression was significantly correlated with late clinical stage (P<0.05 and P<0.01) and poor histological differentiation (both P<0.01). P-AKT expression was significantly correlated with NF-kappaB p65 immunostaining (phi=0.272, P<0.05). Elevated expression of P-AKT was negatively correlated with the survival of ovarian cancer patients, but it was not an independent prognostic factor after multivariate analysis. Overexpression of P-AKT and NF-kappaB p65 were involved in the carcinogenesis and metastasis of ovarian cancer. P-AKT might contribute to the malignant transformation through NF-kappaBp65 upregulation.

Objective: To construct the recombinant eukaryotic expression vector pRNAT-U6.1-siEdg4 which carries small interfering RNA (siRNA) of Edg4 and observe the silencing effect of Edg4 gene targeted siRNA in ovarian cancer cell line SKOV3., Methods: The Edg4 gene-targeted hairpin siRNA sequence was designed according to the Edg4 sequence in Genbank, and the two complementary oligo nucleotide strands were synthesized and annealed and inserted into the pRNAT-U6.1 plasmid to build a recombinant Edg4 siRNA eukaryotic expression vector, which was sequenced and identified to contain the correct Edg4 siRNA sequence. The human ovarian carcinoma cell lines SKOV3 were transfected with the vector using lipofectamine method. The efficiency of transfecting cells was observed with fluorescent microscope and the mRNA expression level of Edg4 gene was detected by real time quantitative PCR. The LPA levels in cell supernatants were detected using a biochemical method. And the apoptosis of SKOV3 cells induced by the vector was evaluated by flow cytometry., Results: The recombinant eukaryotic expression vector was confirmed to contain correct Edg4 siRNA sequence by PCR and sequencing. After transfection large amounts of green fluorescence were seen in plasma and nuclei of SKOV3 cells and the positive cell rates were 64%. The expression level of Edg4 mRNA in transfected SKOV3 cell line was significantly decreased (0.05 +/- 0.01vs 0.29 +/- 0.04, P < 0.05). The decrease in LPA level in the cell supernatants was revealed [(3.0 +/- 1.0) vs (7.5 +/- 2.2)micromol/L, P < 0.05]. The apoptosis rate of transfected SKOV3 was increased obviously (53.38% vs 0.51%, P < 0.05)., Conclusions: We have successfully constructed the recombinant eukaryotic expression vector containing Edg4 gene targeted siRNA (pRNAT-U6.1-siEdg4). The vector could effectively transfect SKOV3 cell line, and obviously suppress the Edg4 mRNA expression and induce cell apoptosis in ovarian cancer cell line SKOV3.

Objective: To analyze the expression of phosphorylated protein kinase B (pAKT) and PTEN protein in ovarian epithelial cancer and to investigate the correlations between their expression and prognosis of ovarian epithelial cancers., Methods: Expression of pAKT and PTEN in 12 normal ovarian tissues, 20 benign tumors, 12 borderline tumors and 80 cases of ovarian epithelial cancers were detected by immunohistochemical method, and their correlations were analyzed., Results: The positive expression of pAKT in normal ovarian and benign tumor tissues were significantly lower than that in ovarian epithelial cancers (8%, 10% vs 55%; P < 0.01), respectively. However, loss of PTEN expression in ovarian epithelial cancers was significantly higher than that in normal ovarian and benign tumor tissues, and the positive rate of PTEN expression were respectively, 45%, 100%, and 80% (P < 0.01). The expression of pAKT and PTEN were correlated with clinical stages, differentiation degree of cancer cells, and metastasis (including lymph node; P < 0.05). But there was no difference with regard to age, histological type and ascites. In ovarian cancers, a negative correlation between expression of pAKT and PTEN was observed (r = -0.444, P < 0.01). A univariate analysis revealed that clinical stage, differentiation degree, lymph node involvement, distant metastasis, pAKT and PTEN expression were correlative factors with prognosis (P < 0.05). Multivariate Cox analysis showed that PTEN and clinical stage were the independent risk factors of prognosis (P < 0.05)., Conclusions: The overexpression of pAKT and absence of PTEN are related to ovarian carcinogenesis and development. Loss of PTEN expression is the independent risk factor of poor prognosis in patients with ovarian epithelial cancers.

Objective: To investigate the regulation of 17beta-estradiol on the membrane estrogen receptor alpha., Methods: The Ishikawa cells were treated with 10(-6) mol/L 17beta-estradiol for 0, 3, 10, 30 minutes and 2, 12, 48 hours, respectively. Another group of Ishikawa cells was treated with 10(-12) mol/L, 10(-10) mol/L, 10(-8) mol/L and 10(-6) mol/L 17beta-estradiol for 30 minutes, respectively. The cells were marked with anti-ERalpha and measured with FACS., Results: The fluorescence intensity of mERalpha increased gradually with the application of estradiol. It reached the peak at the end of 30 minutes. Then it began to decrease gradually. When the cells were treated at low concentration of estradiol the fluorescence intensity of mERalpha was high, especially at 10(-10) mol/L estradiol. Then with the rise of the concentration, the fluorescence intensity decreased., Conclusion: The quantity of mERalpha reached the peak at the end of 30 minutes when treated with estradiol. Then it decreased gradually. When treated with estradiol at different concentrations, its quantity could reach the peak at physiological concentration.

Objective: To observe the influence of estrogen receptor, ICI182780, on proleferation, cell cycle progression and apoptosis in estrogen receptor (ER)-positive and ER-poor endometrial carcinoma cells and to explore the possible preliminary value of ICI182780 treating endometrial carcinoma., Methods: The effects of ICI182780 on proliferation, apoptosis and cell cycle distribution of endometrial cancer cells costimulated with 10(-6) mol/L E2 was detected by monotetrazolium (MTT) assay and fluorescence-activated cell sorting technique., Results: With increased concentrations of E2, values of OD 570 nm for endometrial cancers increased gradually especially in Ishikawa. Cell cycle distribution analysis revealed that percentage of Ishikawa cells at G0-G1 phase decreased and percentage at S phase increased significantly, whereas that of HEC-1A cells did not show significant alteration. In cotreatment of endometrial cancer cells with ICI182780, values of OD 570 nm and numbers of apoptotic cells of Ishikawa cells decreased to basal levels, G0-G1 phase proportion increased, percentage of S phase increased in a time or time-dependent manner. But there was no such alteration in HEC-1A cells., Conclusion: The specific ER antagonist, ICI182780, can inhibit Ishikawa cell propagation induced by E2, make cells apoptosis and block Ishikawa cells at the G1/S transition. Therefore, ICI182780 may be a valid approach to treat ER-positive endometrial carcinoma.

Objective: To analyze if there are membrane estrogen receptors (ER) in endometrial carcinoma and if there is some relationship between membrane ER and nuclear ER., Methods: The cell membrane and total cell ERalpha and ERbeta expressions of high and moderate differentiation endometrial carcinoma cells (Ishikawa and HEC-1A cells) were analyzed. Intermittent immunofluorescence dyeing and fluorescent microscopy were carried out with the cells treated with polyformaldehyde and Triton X-100. Intermittent immunofluorescence dyeing and flow cytometry were carried out with the live cells and the cells treated with Triton X-100 respectively., Results: There were fluorescences on the membrane of the Ishikawa and HEC-1A cells which were treated with polyformaldehyde. When the cells were treated with Triton X-100, the fluorescences were also seen inside the cells. The fluorescence intensity of ERalpha and ERbeta in Ishikawa cell membrane (1.09 +/- 0.21, 1.27 +/- 0.33) was stronger than the control, but there were no significant differences (P > 0.05). When treated with Triton X-100, the total cell fluorescence intensity of ERalpha and ERbeta in Ishikawa cell (4.21 +/- 0.34, 4.69 +/- 1.96) was stronger than the membrane (P < 0.05). The ERalpha and ERbeta fluorescence intensity of HEC-1A cell membrane (1.58 +/- 0.13, 1.49 +/- 0.04) were stronger than the control (P < 0.05). The fluorescence intensity of ERalpha and ERbeta of the HEC-1A cell (2.34 +/- 0.33, 2.52 +/- 0.15) was stronger than the membrane also (P < 0.05). The membrane ERalpha fluorescence intensity of Ishikawa was lower than HEC-1A (P = 0.028). But the total cell ERalpha fluorescence intensity of Ishikawa was higher than HEC-1A (P = 0.002)., Conclusions: There are membrane ER on endometrial carcinoma cells Ishikawa and HEC-1A. The membrane ER must have some similarity to the nuclear receptor. There is no direct correlation between the quantity of the membrane ER and nuclear ER.

Cellular response to estrogen is mediated both by estrogen receptor (ER) binding to estrogen response element (ERE) and by non-nuclear actions like activation of signal transducing pathways. The main aims are to study if PI3K/Akt signaling pathway can be activated by 17beta-estradiol (E2) via non-nuclear action and to investigate the relationship of the action of E2 and ER in endometrial cancer cells expressing with different status of ER. The levels of phosphorylated Akt (Ser473) (P-Akt) and total Akt were examined by western blot and Akt kinase activity was measured in cells after stimulation with 1 microM E2 at different time points. Inhibitory role of LY294002 on activation of Akt induced by E2 and its estrogen antagonist, ICI182780 were also tested. P-Akt/Akt was used as a measure of activation of Akt. We found that maximum P-Akt/Akt and Akt kinase activity took place at 30 min in Ishikawa cells and 15 min in HEC-1A cells and the activation persisted for at least 2 h after stimulation with 1 microM E2. The activation of Akt elicited gradually with increasing doses of E2. PI3K inhibitor, LY294002, stopped the activating Akt in a dose-dependent manner and 50 microM LY294002 completely blocked the activation of Akt induced by E2. ICI182780 could block the activation of PI3K/Akt in ER-positive Ishikawa cells but not in HEC-1A cells with poor-expressed ER. This study demonstrated that E2 is able to promptly activate PI3K/Akt signal pathway in Ishikawa cells in an ER-dependent manner and ER-independent in HEC-1A cells. Blockage of PI3K/Akt cascade may become a potential and effective way to control endometrial carcinoma, especially in ER-negative cancers, which show no response to endocrinal therapy.

Objective: Cellular response to estradiol is mediated both by estrogen receptor (ER) binding to estrogen response element (ERE) and by non-nuclear actions like activation of signal transduction pathways such as mitogen activated protein kinase (MAPK) pathway. However, the signal transduction of estrogen involving phosphatidylinositol 3-kinase-protein kinase B (PI3K-PKB) is not clear in endometrial carcinoma. Our purpose was to study if PI3K-PKB signaling pathway could be activated rapidly by 17beta-E(2) through non-nuclear action and also, whether PI3K inhibitor, LY294002, could inhibit such non-nuclear action of 17beta-E(2) in endometrial carcinoma cell line Ishikawa., Methods: Levels of phosphorylated PKB (Ser473 site, p-PKB) and total PKB were examined by western blotting in Ishikawa cells after stimulation with 17beta-E(2) at 1 x 10(-6) mol/L for different time periods and at varied doses for 30 min. Optimal time and appropriate dose for 17beta-E(2) to activate PKB in Ishikawa cells were observed. Inhibitory effect of LY294002 on activation of PKB induced by 17beta-E(2) was also studied. p-PKB/PKB ratio was used to indicate levels of activation of PKB., Results: p-PKB/PKB at 15 min (0.533 +/- 0.029) was significantly higher than the control (0.361 +/- 0.029, P < 0.05). Maximal activation of PKB (maximal levels of p-PKB/PKB) took place at 30 min (0.666 +/- 0.021, P < 0.001) and the activation persisted at least 2 h after stimulation with 1 x 10(-6) mol/L 17beta-E(2) in Ishikawa cells. With increased doses of 17beta-E(2) (vehicle, 1 x 10(-10), 1 x 10(-8), 1 x 10(-6), 1 x 10(-4) mol/L), the activation of PKB (p-PKB/PKB was 0.300 +/- 0.098, 0.312 +/- 0.081, 0.625 +/- 0.100, 0.771 +/- 0.041, 0.902 +/- 0.043 accordingly) increased gradually (in comparison with vehicle, P > 0.05, < 0.05, < 0.05, < 0.001 accordingly). PI3K inhibitor, LY294002 could inhibit the activation of PKB induced by 17beta-E(2) in Ishikawa cells. Levels of PKB (p-PKB/PKB) decreased (0.443 +/- 0.032, 0.415 +/- 0.032, 0.111 +/- 0.035, 0, 0) gradually with increased concentrations (vehicle, 0.1, 10, 50, 100 micro mol/L) of LY294002 (compared with vehicle, P > 0.05, < 0.05, < 0.001, < 0.001) and 50 micro mol/L LY294002 completely blocked the activation of PKB induced by 17beta-E(2)., Conclusions: 17beta-estradiol, by non-nuclear action, can activate promptly PI3K-PKB signaling pathway in endometrial carcinoma cell line, Ishikawa. This action of 17beta-E(2) is PI3K dependent and can be inhibited or blocked by LY294002.