cytochrome-c-t and Endometrial-Neoplasms

Previously we have shown inhibition of endometrial cancer cell growth with progesterone and calcitriol. However, the mechanisms by which the two agents attenuate proliferation have not been well characterized yet. Herein, we investigated how progesterone and calcitriol induce apoptosis in cancer cells. DNA fragmentation was upregulated by progesterone and calcitriol in ovarian and endometrial cancer cells. Time-dependent treatment of ovarian cancer cells, ES-2, and TOV-21G with progesterone enhanced caspase -8 activity after 12 h, whereas OV-90, TOV-112D, HEC-1A, and HEC-59 cells showed increased activity after 24 h. Caspase 9 activity was increased in all cell lines after 24 h treatment with calcitriol. Pretreatment of cancer cells with a caspase-8 inhibitor (z-IETD-fmk) or caspase-9 inhibitor (Z-LEHD-fmk) significantly attenuated progesterone and calcitriol induced caspase-8 and caspase-9 expression, respectively. The expression of FasL, Fas, FAD, and pro-caspase-8, which constitute the death-inducing signaling complex (DISC), was upregulated in progesterone treated cancer cells. Knockdown of FAS or FADD with specific siRNAs significantly blocked progesterone-induced caspase-8. Cleavage of the BID was not affected by caspase-8 activation suggesting the absence of cross-talk between caspase-8 and caspase-9 pathways. Calcitriol treatment decreased mitochondrial membrane potential and increased the release of cancer cytochrome C. These findings indicate that progesterone induces apoptosis through activation of caspase-8 and calcitriol through caspase-9 activation in cancer cells. A combination of progesterone-calcitriol activates both extrinsic and intrinsic apoptotic pathways in cancer cells.

Topics: Apoptosis; Calcitriol; Caspase 8; Caspase 9; Caspases; Cell Line, Tumor; Cytochromes c; Death Domain Receptor Signaling Adaptor Proteins; Death Domain Superfamily; Endometrial Neoplasms; Fas Ligand Protein; fas Receptor; Female; Humans; In Vitro Techniques; Membrane Potential, Mitochondrial; Ovarian Neoplasms; Progesterone; Signal Transduction

Eclipta prostrate L. (syn. E. alba Hassk), commonly known as False Daisy, has been used in traditional medicine in Asia to treat a variety of diseases, including cancer. Although an anti-tumor effect has been suggested for E. prostrata, the exact anti-tumor effects and underlying molecular mechanisms of its bioactive compounds are poorly understood. The aim of this study was to identify compounds with anti-cancer activity from E. prostrata and to investigate their mechanism of action.. To assess cell viability, cell cycle progression, and apoptosis, we performed MTT assays and FACS analysis using Annexin and PI staining. We also investigated reactive oxygen species (ROS) production and caspase activation using flow cytometry and Western blot analysis, respectively. Cytosolic translocation of cytochrome c was measured using an ELISA kit. Antioxidants, MAPK signaling inhibitors, NADPH oxidase inhibitors, and siRNA were used to elucidate the molecular mechanism of action of the compound.. We isolated five terthiophenes from the n-hexane fraction of E. prostrata; of these, α-terthienylmethanol possessed potent cytotoxic activity against human endometrial cancer cells (Hec1A and Ishikawa) (IC50<1μM). The growth inhibitory effect of α-terthienylmethanol was mediated by the induction of apoptosis, as shown by the accumulation of sub-G1 and apoptotic cells. In addition, α-terthienylmethanol triggered caspase activation and cytochrome c release into the cytosol in a time-dependent manner. Moreover, α-terthienylmethanol increased the intracellular level of ROS and decreased that of GSH, and the antioxidants N-acetyl-l-cysteine and catalase significantly attenuated α-terthienylmethanol-induced apoptosis. We further demonstrated that inhibition of the NADPH oxidase attenuated α-terthienylmethanol-induced cell death and ROS accumulation in endometrial cancer cells.. Overall, these results suggest that α-terthienylmethanol, a naturally occurring terthiophene isolated from E. prostrata, induces apoptosis in human endometrial cancer cells by ROS production, partially via NADPH oxidase.

Topics: Apoptosis; Caspases; Cell Cycle; Cell Line, Tumor; Cell Survival; Cytochromes c; Eclipta; Endometrial Neoplasms; Female; Glutathione; Humans; NADPH Oxidases; Reactive Oxygen Species; Signal Transduction; Thiophenes

Cytochrome c (CytC) released from mitochondria induces apoptosis in both normal and tumor cells. Expression of Fas ligand (FasL) helps maintain tumor cell survival by inducing apoptosis of Fas-bearing anti-tumor immune cells. A risk of endometrial cancer has been reported to associate with phytoestrogen consumption. Therefore the effects of phytoestrogens, genistein and daidzein, on FasL and CytC protein expression were examined in primary cultured porcine endometrial cells (PE) and human cancerous endometrial cells (RL95-2) by Western blot analysis. Both cells were cultured in standard medium (SM) and switched to estrogen-deprived medium (SF) with or without 17beta-estradiol (E, 1 nM), genistein (10 microM) or daidzein (10 microM) for 48 h. FasL (25 kDa) which was found only in RL95-2 cells was upregulated in SF compared to SM. Treatment of RL95-2 cells with E, daidzein or genistein significantly increased the FasL expression by 7-10 folds. In the present study, low level of CytC was detected in both cells cultured in SM but markedly increased in SF by 1.5-2 folds. The SF-induced increase in CytC level was reversed by genistein or daidzein while E suppressed CytC in PE cells, but not in RL95-2 cells. The findings suggest that genistein and daidzein appear to act as a survival factor by inhibiting intracellular apoptogenic initiator in both normal and cancer endometrial cells. In addition, estrogen and phytoestrogens inducing the death signal FasL expressed by cancerous endometrial cells may cause the tumor progression. Thus, consuming phytoestrogen as a supplement should be awareness in patient with endometrial cancer.

Topics: Analysis of Variance; Animals; Apoptosis; Blotting, Western; Cells, Cultured; Cytochromes c; Endometrial Neoplasms; Estradiol; Fas Ligand Protein; Female; Genistein; Humans; Isoflavones; Phytoestrogens; Swine

Histone deacetylase (HDAC) inhibitors are a promising new class of anticancer agents that act by inhibiting cell proliferation and inducing apoptosis in a variety of cancer cells. Although apicidin acts as a potent HDAC inhibitor, the precise mechanism for its anti-tumor activity in human endometrial cancer cells is not completely understood. This study examined the anti-tumor effects of apicidin in Ishikawa cancer cells. The level of cell proliferation, the stage of the cell cycle, and apoptosis were measured after the apicidin treatment. Apicidin significantly inhibited the proliferation of Ishikawa cells in a dose-dependent manner. In addition, apicidin markedly up-regulated the p21(WAF1) and down-regulated the expression of cyclins (A, B1, D1, or E), and CDKs (2 or 4), which leading to cell cycle arrest. Cell cycle analysis showed that the apicidin treatment increased the proportion of cells in the G1 phase, and decreased the ratio of cells in the S phase in a dose-dependent manner. Apicidin significantly increased the sub-G1 population and the number of TUNEL positive apoptotic cells compared with the untreated control. These results were confirmed by poly-ADP ribose polymerase (PARP), an 85-kDa fragment resulting from PARP cleavage, where apicidin increased the level of PARP cleavage and caspase-3 activity in 1.0 microM apicidin-treated cells. Apicidin-induced apoptosis through caspase-3 activation was confirmed by the increase in the release of cytochrome c and the decrease in the Bax/Bcl-2 ratio. These results suggest that apicidin has anti-tumor properties on endometrial cancer cells by inducing selectively the genes related to cell cycle arrest and apoptosis.

Topics: Antineoplastic Agents; Apoptosis; Blotting, Western; Caspase 3; Cell Cycle; Cell Proliferation; Cyclin-Dependent Kinase Inhibitor p21; Cyclin-Dependent Kinases; Cyclins; Cytochromes c; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Endometrial Neoplasms; Female; G1 Phase; Gene Expression Regulation, Neoplastic; Histones; Humans; Peptides, Cyclic; Proto-Oncogene Proteins c-bcl-2; Reverse Transcriptase Polymerase Chain Reaction; Tumor Cells, Cultured

1,1-Bis(3'-indolyl)-1-(p-substituted phenyl)methanes, containing p-t-butyl (DIM-C-pPhtBu) and phenyl (DIM-C-pPhC(6)H(5)) substituents, are peroxisome proliferator-activated receptor gamma (PPARgamma) agonists; however, DIM-C-pPhtBu-induced growth inhibition and cell death in human HEC1A endometrial cancer cells is PPARgamma-independent. DIM-C-pPhtBu decreased mitochondrial membrane potential (MMP) and promoted the release of cytochrome c and caspase activation and nuclear uptake of endonuclease G leading to apoptosis of HEC1A cells. DIM-C-pPhtBu specifically targeted the mitochondrial permeability transition pore complex (PTPC) because the DIM-C-pPhtBu-induced pro-apoptotic responses were inhibited by atractyloside (Atra), a compound that specifically interacts with the inner mitochondrial membrane adenine nucleotide transport (ANT) proteins. At the dose of Atra used in this study (300 microM), this compound alone did not alter the PTPC but inhibited the mitochondriotoxic effects of DIM-C-pPhtBu. DIM-C-pPhtBu/DIM-C-pPhC(6)H(5) and Atra also differentially affected the ability of eosin-5-maleimide (EMA) to alkylate Cys160 in the ANT protein and Atra, but not DIM-C-pPhtBu, inhibited the exchange of ATP/ADP in isolated mitochondria suggesting that these pharmacophores act on different sites on the ANT protein. Results of this study show that the receptor-independent proapoptotic activity of DIM-C-pPhtBu and DIM-C-pPhC(6)H(5) were related to novel mitochondriotoxic activities involving inner mitochondrial ANT proteins.

Topics: Adenine Nucleotide Translocator 1; Adenosine Triphosphate; Alkylation; Apoptosis; Atractyloside; Blotting, Northern; Blotting, Western; Caspases; Cell Proliferation; Cytochromes c; Endometrial Neoplasms; Enzyme Activation; Enzyme-Linked Immunosorbent Assay; Female; Fluorescent Antibody Technique; Humans; Indoles; Membrane Potential, Mitochondrial; Pancreatic Neoplasms; PPAR gamma; Reverse Transcriptase Polymerase Chain Reaction; Tumor Cells, Cultured

The biological functions and reaction pathways of lipocalins in mammalian system were sought. Mouse uterine 24p3 protein is a secreted lipocalin from mouse uterus. To evaluate the effect of uterine 24p3 protein on the reproductive system, endometrial carcinoma cell line (RL95-2) was an experimental target for achieving the in vitro study. The cells were treated with 0.75 microM dexamethasone (DEX) or under serum-free medium to mimic the stress environment for various time periods, then employing Western blot to measure the 24p3 protein secretion. It showed the time-dependent induction effect on 24p3 protein and suggested the level of protein secretion correlating to environmental stress. Furthermore, the supplementation of 24p3 protein to the medium accompanied the reduction of cell viability. It showed that the 24p3 protein may be a death factor under conditional media via PI and annexinV-FITC assay. Based on the autocrine hypothesis, we investigated the effect of 24p3 protein on cultured RL95-2 cells upon the 24p3 protein interaction. We have demonstrated significant increase in intracellular reactive oxygen species upon 24p3 protein interaction. While the changes of mitochondrial membrane potential and cytochrome c release from mitochondria occurred, the activities of caspase-8, -9 and -3 were found to have increased. The condensation of DNA was occurred suggesting that 24p3 protein induced irreparable DNA damage, which in turn triggered the process of apoptosis. It shows evidence for the direct effect of this protein on endometrial cells. These findings suggest that 24p3 protein creates an intracellular oxidative environment that induces apoptosis in RL95-2 cells.

Topics: Acute-Phase Proteins; Apoptosis; Blotting, Western; Carcinoma; Caspases; Cell Line, Tumor; Cell Survival; Coloring Agents; Culture Media; Cytochromes c; Dexamethasone; DNA, Neoplasm; Endometrial Neoplasms; Female; Flow Cytometry; Fluorescein-5-isothiocyanate; HeLa Cells; Humans; Lipocalin-2; Lipocalins; Membrane Potentials; Microscopy, Fluorescence; Mitochondria; Proto-Oncogene Proteins; Reactive Oxygen Species; Trypan Blue; Uterus

Human endometrial epithelial cells undergo apoptosis immediately before the menstrual period. Apoptotic signalling was analysed using human endometrial tissue and a human endometrial carcinoma cell line (HHUA). Activity levels of caspase-3, -8, and -9 were elevated in human endometrium during the late secretory phase and in HHUA cells incubated with an anti-Fas monoclonal antibody (mAb). Fas-mediated apoptosis of HHUA cells was blocked by prior exposure to inhibitors of caspase-9, -8 and -3. In HHUA cells treated with anti-Fas mAb, a release of cytochrome c was detected in the cytosolic fraction, in addition a full-length Bid was degraded. Full-length FLIP(L) (p55) was degraded during apoptosis, and p29 (regarded as the product of p55 cleavage) appeared instead of FLIP(L). In normal human endometrial tissue, Bid degradation was also observed in a cyclic manner with a peak during the early secretory phase of the menstrual cycle. Furthermore, the release of cytochrome c was seen in the early secretory phase. However, expression of FLIP(S) was only observed during the menstrual cycle in normal endometrial tissue. We concluded that the main apoptotic signalling in both normal human endometrial tissue and HHUA cells exposed to anti-Fas mAb is the mitochondrial pathway via Bid degradation. Although the function of FLIP is still unknown on normal endometrial tissue, it may be regulated by FLIP(L) expression on HHUA cells derived from human endometrial carcinoma.

Topics: Adult; Amino Acid Chloromethyl Ketones; Antibodies, Monoclonal; Antibodies, Monoclonal, Murine-Derived; Apoptosis; BH3 Interacting Domain Death Agonist Protein; CASP8 and FADD-Like Apoptosis Regulating Protein; Caspase Inhibitors; Caspases; Cell Line, Tumor; Cell Proliferation; Cysteine Proteinase Inhibitors; Cytochromes c; DNA Fragmentation; Dose-Response Relationship, Drug; Endometrial Neoplasms; Endometrium; Epithelial Cells; Estradiol; fas Receptor; Female; Humans; Immunohistochemistry; Intracellular Signaling Peptides and Proteins; Menstrual Cycle; Middle Aged; Progesterone; Receptors, Tumor Necrosis Factor; Reverse Transcriptase Polymerase Chain Reaction; Signal Transduction; Time Factors

The goal of this study was to examine the effect of ursolic acid, a pentacyclic triterpenoid compound, on growth of the endometrial cancer cell line SNG-II. We found that ursolic acid strongly inhibited the growth of SNG-II cells in a dose- and time-dependent manner. Morpholgical changes characteristic of apoptosis were observed in treated cells, such as the presence of apoptotic bodies and fragmentation of DNA into oligonucleosomal-sized fragments. We also investigated the active forms of caspase-3, -8 and -9 in ursolic acid-treated SNG-II cells. At 25 and 50 microM strength, ursolic acid induced marked increases in caspase-3 activity to approximately 5-fold that of control cells. Levels of cleaved caspase-3 increased in a time- and dose-dependent manner. Activation of caspases also led to the cleavage of target proteins, such as PARP. Ursolic acid treatment also resulted in a cleavage of poly (ADP-ribose) polymerase in a dose-dependent manner. Testing whether caspase-3 activation and DNA polymerase activity were inhibited by addition of Ac-DEDV-HCO during ursolic acid treatment showed that 50 microM Ac-DEDV-HCO inhibited caspase-3 activity in treated cells. Although DNA fragmentation was observed after ursolic acid treatment, DNA fragmentation did not occur in SNG II cells treated with both Ac-DEDV-HCO and ursolic acid. Because some researchers have suggested that mitochondrial pathways are involved in ursolic acid-induced apoptosis secondary to induction of mitochondrial cytochrome c release, we studied mitochondrial events in ursolic acid-induced apoptosis in these cell lines. After ursolic acid treatment, the anti-apoptotic Bcl-2 protein decreased and Bax expression was enhanced. Our results indicated that ursolic acid induced apoptotic processes in the endometrial cancer SNG-II cell line through mechanisms involving mitochondrial pathways and Bcl-2 family proteins.

Topics: Antineoplastic Agents, Phytogenic; Apoptosis; bcl-2-Associated X Protein; Caspase 3; Caspase Inhibitors; Caspases; Cell Line, Tumor; Cytochromes c; DNA; DNA Fragmentation; Endometrial Neoplasms; Female; Humans; Mitochondria; Oligopeptides; Poly(ADP-ribose) Polymerases; Proto-Oncogene Proteins c-bcl-2; Triterpenes; Up-Regulation; Ursolic Acid

We studied the effect of ursolic acid, a pentacyclic triterpene acid, on the growth of poorly differentiated type endometrial cancer HEC108 cells in vitro. Ursolic acid strongly inhibited the growth of HEC108 cells in a dose- and time-dependent manner. Morphological changes characteristic of apoptosis were observed in ursolic acid-treated cells, such as the presence of apoptotic bodies and fragmentation of DNA to oligonucleosomal-sized fragments. Investigation of caspase activity in ursolic acid-treated HEC108 cells showed that exposure at 50, 75 or 100 microM induced marked increases in caspase-3 activity (after 24 h) to 5.00, 11.76 or 12.75 times that of control levels, while cleaved caspase-3 levels increased in dose-dependent manner after 24 h. Activation of caspase was shown to lead to the cleavage of target proteins such as PARP. Ursolic acid treatment also resulted in a cleavage of poly(ADP-ribose) polymerase in a dose-dependent manner. Testing whether caspase-3 activation and DNA polymerase activity were inhibited by the addition of Ac-DEDV-HOC during ursolic acid treatment showed that 50 microM Ac-DEDV-HOC inhibited caspase-3 activity in treated cells. A mitochondrial pathway has been suggested to be involved in ursolic acid-induced apoptosis because the treatment induces mitochondria cytochrome c release. Experimentally, we found that anti-apoptotic Bcl-2 protein levels decreased after ursolic acid treatment, while Bax expression increased. Our results indicated that ursolic acid induced apoptotic processes in these poorly differentiated endometrial cancer cells occurs through mechanisms involving mitochondrial pathways and Bcl-2 family proteins.

Topics: Antineoplastic Agents, Phytogenic; Apoptosis; Apoptotic Protease-Activating Factor 1; bcl-2-Associated X Protein; Caspase 3; Caspase Inhibitors; Caspases; Cell Line, Tumor; Cell Proliferation; Cysteine Proteinase Inhibitors; Cytochromes c; DNA Fragmentation; Dose-Response Relationship, Drug; Endometrial Neoplasms; Female; Humans; Oligopeptides; Poly(ADP-ribose) Polymerases; Proteins; Proto-Oncogene Proteins c-bcl-2; Time Factors; Triterpenes; Ursolic Acid