Apoptosis: a programmed cell death involved in ovarian and uterine physiology

Expression levels of BCL2 and MKI67 in endometrial polyps in postmenopausal women and their correlation with obesity

Obesity is associated with numerous diseases, including endometrial disorders in postmenopausal women, such as adenocarcinoma, hyperplasias and endometrial polyps, and the risk of malignant transformation of these structures. The present study evaluated the influence of body mass index (BMI) on cell proliferation (BCL2 and MKI67) in endometrial polyps in postmenopausal women. A prospective cross-sectional study using immunohistochemical analysis of the expression of a cell proliferation marker (MKI67) and an anti-apoptotic gene (BCL2) in endometrial polyps in postmenopausal women was performed. The patients were divided into three groups depending on BMI: i) <24.9 kg/m² (normal); ii) >25 and <29.9 kg/m² (overweight); and iii) >30 kg/m² (obese). The present study analyzed the expression of these markers in relation to polyp size, histological type and time since menopause in 38 patients. The interpretation of MKI67 and BCL2 expression accounted for the percentage of positive cells (scores): 1 (weak), <5% of cells showed expression; 2 (moderate), between 5 and 50%; and 3 (intense), >50%. Statistical analysis was performed using GraphPad InStat version 3.00 software. ANOVA was used to analyze BCL2 and MKI67 expression. A significance level of P<0.05 was adopted for rejecting the null hypothesis. There was greater glandular expression of MKI67 in obese women than in normal weight women (P=0.02) and greater expression of BCL2 in the stroma of polyps >2 cm (P=0.03). Hyperplastic polyps exhibited hyperexpression of MKI67 (P=0.04) compared with atrophic polyps. No difference in MKI67 and BCL2 expression was identified in the glands and stroma of polyps when comparing overweight and obese postmenopausal patients. The present findings suggest that BMI has an influence on proliferation markers (MKI67) in the polyps of postmenopausal women and that polyps >2 cm exhibit hyperexpression of BCL2 in the stroma.

Immunohistochemical assessment of symptomatic postmenopausal endometrial polyps in tamoxifen users and nonusers: a case control study

BACKGROUND

Endometrial polyps are common in postmenopausal women, and the effect of tamoxifen use (a risk factor for endometrial polyps) on their pathogenesis is unclear.

OBJECTIVES

To evaluate the expression of hormone receptors and markers for proliferation/apoptosis (Ki-67 and Bcl-2) in endometrial polyps in postmenopausal users and nonusers of tamoxifen.

DESIGN AND SETTING

Cross-sectional analytical study in a tertiary-level academic hospital.

METHODS

46 women (14 tamoxifen users and 32 nonusers) with postmenopausal bleeding underwent hysteroscopic resection of endometrial polyps. Polyp samples were immunohistochemically assessed for detection of Ki-67, Bcl-2 and estrogen and progesterone receptors.

RESULTS

Analysis on the glandular component of the polyps revealed progesterone receptor expression in the polyps of 96.9% of the nonusers of tamoxifen, and 92.3% of the tamoxifen users (P = 0.499). All polyps in nonusers and 92.3% of those in users were also positive for estrogen receptors (P = 0.295). Ki-67 was expressed in 75% of the polyps in the tamoxifen users and 82.8% of those in the nonusers. All endometrial polyps expressed Bcl-2.

CONCLUSIONS

The immunohistochemical analysis on endometrial polyps demonstrated that, although tamoxifen is considered to be a risk factor for endometrial polyps, there were no significant differences in the expression of hormone receptors between users and nonusers of tamoxifen. There were no between-group differences in Ki-67 and Bcl-2 expression, and all patients displayed inhibition of apoptosis by Bcl-2, thus supporting the theory that polyps develop due to inhibition of apoptosis, and not through cell proliferation.

The role of chamaejasmine in cellular apoptosis and autophagy in MG-63 cells

Background: Osteosarcoma (OS) is the most common malignant neoplasm in children and adolescents with a very high propensity for local invasion and poor response to current therapy. Anti-cancer effect of chamaejasmine is newly discovered from Stellera chamaejasmine L. Our study focuses on investigating the effect of chamaejasmine on the cellular apoptosis, proliferation, autophagy, and the underlying mechanisms in MG-63.

Methods: Our study investigated the concentration of chamaejasmine in MG-63 cells by MTT and verified that chamaejasmine inhibited cell invasion by transwell. We also used Hoechst staining as well as apoptotic associated-proteins in MG-63 cells. Meanwhile, we also detected the lysophagesome and autophagsome by Lysotracker. Adenosine 5′-monophosphate (AMP)-activated protein kinase (AMPK) knockdown was performed with siRNA.

Results: Our results show that chamaejasmine exerts cellular growth inhibition, pro-apoptotic and pro-autophagic effect via activating AMPK in MG-63 cells. Furthermore, chamaejasmine significantly increases autophagic cell via the inhibition of mammalian target of rapamycin (mTOR) and activation of AMPK signaling pathways. Administrated with chamaejasmine also induces reactive oxygen species (ROS) generation, indicating cross-talking between these two primary modes of programmed cell death.

Conclusion: Our results show that chamaejasmine promotes apoptosis and autophagy by activating AMPK/mTOR signaling pathways with involvement of ROS in MG-63 cells. Chamaejasmine is a promising anti-cancer agent in OS treatment, and further studies are needed to confirm its efficacy and safety in vivo or other cancer cells.

miR-30d inhibits cell biological progression of Ewing's sarcoma by suppressing the MEK/ERK and PI3K/Akt pathways in vitro

MicroRNAs (miRNAs) are small, single-stranded, non-coding RNA molecules involved in cancer initiation and progression. The present study aimed to determine the effect of miRNA-30d (miR-30d) on the growth, malignant phenotype, and apoptosis of Ewing's sarcoma (ES) SK-ES-1 cells, and to elucidate the underlying molecular mechanism and signaling pathway involved. Cell proliferation, invasion, migration, morphological changes, cell cycle distribution and apoptosis were investigated. Furthermore, the expression of matrix metalloproteinase (MMP)-2, MMP-9, B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), caspase-3 and poly (ADP-ribose) polymerase (PARP) were examined, as was the activity of the mitogen-activated protein kinase kinase (MEK)/extracellular signal-regulated kinase (ERK) and phosphoinositide 3-kinase (PI3K)/Akt pathways. It was found that the overexpression of miR-30d repressed the proliferation, migration and invasion, and promoted morphological changes, S-phase arrest and apoptosis of SK-ES-1 cells. Additionally, it was observed that increased miR-30d levels inhibited the expression of MMP-2 and MMP-9, and inhibited the activity of the MEK/ERK and PI3K/Akt pathways, but elevated the ratio of Bax/Bcl-2 and the cleavage of caspase-3 and PARP. Taken together, the results demonstrated that miR-30d suppressed the biological progression of SK-ES-1 cells by targeting MMP-2 and MMP9, the Bax/Bcl-2 and caspase-3 cascade, and the MEK/ERK and PI3K/Akt signaling pathways. Therefore, miR-30d is a promising target in the treatment of ES. However, further investigations are urgently required to investigate the underlying molecular mechanisms of the effects of miR-30d on ES for a comprehensive understanding of the tumorigenesis and progression of this cancer.

Fas-Related Apoptosis of Peritoneal Fluid Macrophages in Endometriosis Patients: Understanding the Disease

Recent studies of the peritoneal cavity environment in endometriosis demonstrate quantitative and qualitative changes in the cells responsible for cell-mediated immunity. Such changes may have led to disturbances in the surveillance, recognition, and destruction of misplaced endometrial cells and might have, in fact, brought about the disease. The aim of the study was to assess CD95 (Fas) expression on (activated) peritoneal fluid (PF) macrophages, as well as to ascertain soluble Fas (sFas) concentration in the PF of endometriosis patients, as compared to the nonendometriotic group. The concentration of leukocytes in the PF, the percentage of cells expressing CD45⁺/CD14⁺, and the percentage of PF macrophages expressing the HLA-DR antigen were significantly higher in patients with stages I and II endometriosis. The percentage of Fas- (CD95⁺-) expressing macrophages was significantly higher in all stages of the disease, in comparison with controls. Moreover, the concentration of sFas in the PF of patients with moderate and severe endometriosis was significantly higher, as compared to the reference group. The high number of immune cells in PF in early stage endometriosis and their increased susceptibility to apoptosis confirm the role of the impaired peritoneal environment and immune defects in the development and progression of the disease.

Photoinduced ROS regulation of apoptosis and mechanism studies of iridium(iii) complex against SGC-7901 cells

A new iridium(iii) complex, Ir(ppy)₂(FBPIP)]PF₆ (Ir-1), was synthesized and characterized. The anticancer activity of the complex was investigated by cytotoxicity in vitro, apoptosis, cell invasion, autophagy, cell cycle arrest and western blot.

Copper induced apoptosis in Caco-2 and Hep-G2 cells: Expression of caspases 3, 8 and 9, AIF and p53

Copper (Cu) is an essential trace metal needed to ensure cell function. However, when present at high concentrations it becomes toxic to organisms. Cell death, induced by toxic levels of copper, was previously observed in in vitro studies. However, there is no consensus about the cell death pathway induced by Cu and it is still not known whether this occurs as a result of the direct action of the metal or by indirect effects. In the present work, we intend to identify the influence of different Cu concentrations in the induction of apoptosis and to explore the potential signaling pathways, using two different in vitro cell culture models (Caco-2 and Hep-G2). Cells were exposed, during 6, 12, 24 and 48h, to Cu concentrations corresponding to IC50 and 1/8 of IC50, according to the viability assays. Then, considering the different apoptosis pathways, the expression of caspases 3, 8 and 9, apoptosis inducing factor (AIF) and p53 genes was analyzed by quantitative real time PCR. The results suggested that different Cu concentrations could trigger different apoptotic pathways, at different times of exposure. In both cell lines, apoptosis seems to be initiated by caspase independent pathway and intrinsic pathway, followed by extrinsic pathway. In conclusion, this study demonstrates that Cu induces the activation of apoptosis through caspase dependent and independent pathways, also suggesting that apoptosis activation mechanism is dependent on the concentration, time of exposure to Cu and cell type.

[Immunological aspects of ovarian cancer: Therapeutic perspectives]

Ovarian cancer is recognized by the immunological system of its host. Initially, it is effective to destroy and eliminate the cancer. But gradually, resistant tumor cells more aggressive and those able to protect themselves by inducing immune tolerance will be selected. Immunotherapy to be effective should consider both components of immune response with an action on cytotoxic immune effectors and action on tolerance mechanisms. The manipulations of the immune system should be cautious, because the immune effects are not isolated. A theoretically efficient handling may simultaneously cause an adverse effect which was not envisaged and could neutralize the benefits of treatment. Knowledge of tolerance mechanisms set up by the tumor is for the clinician a prerequisite before they prescribe these treatments. For each cancer, the knowledge of its immunological status is a prerequisite to propose adapted immunological therapies.

Design, synthesis and preliminary biological studies of pyrrolidine derivatives as Mcl-1 inhibitors

Anti-apoptotic proteins, such as B-cell lymphoma (Bcl-2) protein, myeloid cell leukemia sequence 1 (Mcl-1) protein, are potential targets for cancer treatment. In the studies, a series of pyrrolidine derivatives were developed as potent Mcl-1 inhibitors. The preliminary biological studies suggested that most of target compounds exhibit good abilities for targeting Mcl-1 protein. Among them, compound 21 (Ki=0.53μM) exhibited equal inhibitory activities towards Mcl-1 protein compared to positive control gossypol (Ki=0.39μM). This compound also possessed good antiproliferative activities against MDA-MB-231 and PC-3 cancer cells.

Petroselinum crispum has antioxidant properties, protects against DNA damage and inhibits proliferation and migration of cancer cells

BACKGROUND

Petroselinum crispum (English parsley) is a common herb of the Apiaceae family that is cultivated throughout the world and is widely used as a seasoning condiment. Studies have shown its potential as a medicinal herb. In this study, P. crispum leaf and stem extracts were evaluated for their antioxidant properties, protection against DNA damage in normal 3T3-L1 cells, and the inhibition of proliferation and migration of the MCF-7 cells.

RESULTS

The dichloromethane extract of P. crispum exhibited the highest phenolic content (42.31 ± 0.50 mg GAE g(-1) ) and ferric reducing ability (0.360 ± 0.009 mmol g(-1) ) of the various extractions performed. The extract showed DPPH radical scavenging activity with an IC50 value of 3310.0 ± 80.5 µg mL(-1) . Mouse fibroblasts (3T3-L1) pre-treated with 400 µg mL(-1) of the extract showed 50.9% protection against H2 O2 -induced DNA damage, suggesting its potential in cancer prevention. The extract (300 µg mL(-1) ) inhibited H2 O2 -induced MCF-7 cell migration by 41% ± 4%. As cell migration is necessary for metastasis of cancer cells, inhibition of migration is an indication of protection against metastasis.

CONCLUSION

Petroselinum crispum has health-promoting properties with the potential to prevent oxidative stress-related diseases and can be developed into functional food.

Ellagic acid induces apoptosis in TSGH8301 human bladder cancer cells through the endoplasmic reticulum stress- and mitochondria-dependent signaling pathways

To investigate the effects of ellagic acid on the growth inhibition of TSGH8301 human bladder cancer cells in vitro, cells were incubated with various doses of ellagic acid for different time periods. The phase-contrast microscope was used for examining and photographing the morphological changes in TSGH8301 cells. Flow cytometric assay was used to measure the percentage of viable cells, cell cycle distribution, apoptotic cells, ROS, mitochondrial membrane potential (ΔΨm), Ca(2+) , caspase-9 and -3 activities in TSGH8301 cells after exposure to ellagic acid. Western blotting was used to examine the changes of cell cycle and apoptosis associated proteins levels. Results indicated that ellagic acid induced morphological changes, decreased the percentage of viable cells through the induction of G0/G1 phase arrest and apoptosis, and also showed that ellagic acid promoted ROS and Ca(2+) productions and decreased the level of ΔΨm and promoted activities of caspase-9 and -3. The induction of apoptosis also confirmed by annexin V staining, comet assay, DAPI staining and DNA gel electrophoresis showed that ellagic acid induced apoptosis and DNA damage in TSGH8301 cells. Western blotting assay showed that ellagic acid promoted p21, p53 and decreased CDC2 and WEE1 for leading to G0/G1 phase arrest and promoting BAD expression, AIF and Endo G, cytochrome c, caspase-9 and -3 for leading to apoptosis in TSGH8301 cells. On the basis of these observations, we suggest that ellagic acid induced cytotoxic effects for causing a decrease in the percentage of viable cells via G0/G1 phase arrest and induction of apoptosis in TSGH8301 cells.

Nanotoxicity comparison of four amphiphilic polymeric micelles with similar hydrophilic or hydrophobic structure

Background

Nanocarriers represent an attractive means of drug delivery, but their biosafety must be established before their use in clinical research.

Objectives

Four kinds of amphiphilic polymeric (PEG-PG-PCL, PEEP-PCL, PEG-PCL and PEG-DSPE) micelles with similar hydrophilic or hydrophobic structure were prepared and their in vitro and in vivo safety were evaluated and compared.

Methods

In vitro nanotoxicity evaluations included assessments of cell morphology, cell volume, inflammatory effects, cytotoxicity, apoptosis and membrane fluidity. An umbilical vein cell line (Eahy.926) and a kind of macrophages (J774.A1) were used as cell models considering that intravenous route is dominant for micelle delivery systems. In vivo analyses included complete blood count, lymphocyte subset analysis, detection of plasma inflammatory factors and histological observations of major organs after intravenous administration to KM mice.

Results

All the micelles enhanced inflammatory molecules in J774.A1 cells, likely resulting from the increased ROS levels. PEG-PG-PCL and PEEP-PCL micelles were found to increase the J774.A1 cell volume. This likely correlated with the size of PEG-PG-PCL micelles and the polyphosphoester structure in PEEP-PCL. PEG-DSPE micelles inhibited the growth of Eahy.926 cells via inducing apoptosis. This might relate to the structure of DSPE, which is a type of phospholipid and has good affinity with cell membrane. No evidence was found for cell membrane changes after treatment with these micelles for 24 h. In the in vivo study, during 8 days of 4 time injection, each of the four nanocarriers altered the hematic phase differently without changes in inflammatory factors or pathological changes in target organs.

Conclusions

These results demonstrate that the micelles investigated exhibit diverse nanotoxicity correlated with their structures, their biosafety is different in different cell model, and there is no in vitro and in vivo correlation found. We believe that this study will certainly provide more scientific understandings on the nanotoxicity of amphiphilic polymeric micelles.

Antitumor activity of a sulfated polysaccharide from Enteromorpha intestinalis targeted against hepatoma through mitochondrial pathway

A sulfated polysaccharide (EI-SP), extracted from Enteromorpha intestinalis that is a kind of algae, is found to have anticancer activity. This study was designed to investigate the anti-tumor effect of EI-SP on human hepatoma HepG2 cell line and its possible mechanisms. An MTT assay showed that EI-SP could specifically inhibit the growth of human hepatoma HepG2 cells in a dose-dependent manner. Analysis by flow cytometry indicated that the apoptosis of tumor cells increased after treatment with EI-SP in range of 100-400 μg/ml. Furthermore, Western blot analysis showed that EI-SP treatment led to decreased protein expression of Bcl-2 and an increase in Bax, cleaved caspase-3, cleaved caspase-9 and cleaved poly(ADP-ribose) polymerase (PARP). Moreover, it was found that EI-SP caused a loss of mitochondrial membrane potential (Δψ m) and the release of cytochrome c to the cytosol. Collectively, our results showed that the EI-SP induces apoptosis in HepG2 cells involving a caspases-mediated mitochondrial signalling pathway.

Pregnancy-associated genes contribute to antiluteolytic mechanisms in ovine corpus luteum

The hypothesis that ovine luteal gene expression differs due to pregnancy status and day of estrous cycle was tested. RNA was isolated from corpora lutea (CL) on days 12 and 14 of the estrous cycle (NP) or pregnancy (P) and analyzed with the Affymetrix bovine microarray. RNA also was isolated from luteal cells on day 10 of estrous cycle that were cultured for 24 h with luteolytic hormones (OXT and PGF) and secretory products of the conceptus (IFNT and PGE2). Differential gene expression (>1.5-fold, P < 0.05) was confirmed using semiquantitative real-time PCR. Serum progesterone concentrations decreased from day 12 to day 15 in NP ewes (P < 0.05) reflecting luteolysis and remained >1.7 ng/ml in P ewes reflecting rescue of the CL. Early luteolysis (days 12-14) was associated with differential expression of 683 genes in the CL, including upregulation of SERPINE1 and THBS1. Pregnancy on day 12 (55 genes) and 14 (734 genes) also was associated with differential expression of genes in the CL, many of which were ISGs (i.e., ISG15, MX1) that were induced when culturing luteal cells with IFNT, but not PGE2. Finally, many genes, such as PTX3, IL6, VEGF, and LHR, were stabilized during pregnancy and downregulated during the estrous cycle and in response to culture of luteal cells with luteolytic hormones. In conclusion, pregnancy circumvents luteolytic pathways and activates or stabilizes genes associated with interferon, chemokine, cell adhesion, cytoskeletal, and angiogenic pathways in the CL.

Arginine modified PAMAM dendrimer for interferon beta gene delivery to malignant glioma

A xenograft brain tumor model was established by the subcutaneous injection of U87MG cells into nude mice to investigate the efficacy of a non-viral vector, arginine-modified polyamidoamine dendrimer (PAMAM-R), in delivering a therapeutic gene, human interferon beta (IFN-β). We used 4',6-diamidino-2-phenylindole staining, the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) assay, and the caspase-3 activity assay to determine the induction of apoptosis upon transfection with the PAMAM-R/IFN-β gene polyplex in vitro. The polyplex was injected into xenograft brain tumors. Mice treated with PAMAM-R/pORF-IFN-β exhibited a significantly smaller tumor size than control mice and PAMAM-R/pORF treated mice. Hematoxylin/eosin staining and immunohistochemistry with the endothelial growth factor receptor antibody also revealed inhibition of tumor growth. Furthermore, reverse transcription polymerase chain reaction and the TUNEL assay also verified the expression of IFN-β and induction of apoptosis in vivo. These results indicate that the PAMAM-R/pORF-IFN-β polyplex is an effective therapeutic candidate for glioblastoma multiforme due to its selective induction of apoptosis in tumor cells.

Chamaejasmine arrests cell cycle, induces apoptosis and inhibits nuclear NF-κB translocation in the human breast cancer cell line MDA-MB-231

In this study, the anticancer activity of chamaejasmine was characterized in the human breast cancer cell line, MDA-MB-231. Cell viability and cell cycle distribution were determined by MTT assay and flow cytometry, respectively. Western blotting was performed to determine changes in levels of various proteins. Results showed that treatment with chamaejasmine (4–16 μM) inhibited cell proliferation, which correlated with G2/M phase arrest and apoptosis in MDA-MB-231 cells. Chamaejasmine treatment of MDA-MB-231 cells resulted in induction of WAF1/p21 and KIP1/p27, decrease in cyclins A and cyclins B1. Cyclin-dependent kinase (cdk) 2 and cdc2 was also decreased after chamaejasmine treatment. Moreover, inhibition of nuclear translocation, phosphorylation of NF-κB, activation of IKKα and IKKβ, inhibition of phosphorylation and degradation of IκBα were also detected in this work. Our findings suggested that chamaejasmine could be explored as a preventive and perhaps as a chemotherapeutic agent in the management of breast cancer.

[Immunological analogies between ovarian cancer and pregnancy]

During pregnancy an environment allowing installation of tolerance toward the fetus is set up locally at the materno-fetal interface. Numerous effectors of immunity are involved in this tolerance (NK cell, T cell, Macrophages, dendritic cell). Specific mechanisms during pregnancy attract locally these immunological cells. In the decidua, they are educated toward tolerance. These mechanisms evolve during the pregnancy because at the end of the pregnancy, tolerance is broken to prepare and activate the labor. Ovarian tumors, after having surmounted the immunosurveillance, like trophoblast, chair the installation of a tolerance of their host facilitating the development of the disease. The blocking of these mechanisms of tolerance coupled with activation of mechanisms of defenses offer new perspectives in the treatment of the ovarian cancer. The authors suggest showing the analogies of the tolerance observed during ovarian cancer and pregnancy. The knowledge of the orchestration of the physiological mechanisms observed during pregnancy will offer new therapeutic targets.

[Immunological aspect of pregnancy]

Pregnancy is a temporary semi-allograft that survives for nine months. The importance of this event for the survival of the species justifies several tolerance mechanisms that are put into place at the beginning of pregnancy, some of which occur even at the time of implantation. The presence of multiple tolerance mechanisms and the richness of the means employed underline the central importance of the trophoblast. Understanding these mechanisms, and in particular, their integration into an overall scheme, enables the anomalies encountered in certain pathologies of pregnancy to be placed into context. Understanding these mechanisms and their interruption at the end of pregnancy should improve our understanding of disappointing results from current immunological treatments facilitate the implementation of new prophylactic and therapeutic strategies.

Apoptosis- and endoplasmic reticulum stress-related genes were regulated by estrogen and progesterone in the uteri of calbindin-D(9k) and -D(28k) knockout mice

Calcium (Ca(2+)) is an important regulator of apoptotic signaling. Calbindin-D(9k) (CaBP-9k) and -D(28k) (CaBP-28k) have a high affinity for Ca(2+) ions. Uterine calbindins appear to be involved in the regulation of myometrial activity by intracellular Ca(2+). In addition, uterine calbindins are expressed in the mouse endometrium and are regulated by steroid hormones during implantation and development. The aim of the present study was to evaluate the regulation of apoptosis in the uteri of CaBP-9k, CaBP-28k, and CaBP-9k/28k knockout (KO) mice. Our findings indicated that Bax protein was enhanced in the uteri of CaBP-28k and CaBP-9k/28k KO mice compared to wild-type (WT) and CaBP-9k KO mice, but no difference was observed in Bcl-2 protein expression. The expressions of caspase 3, 6, and 7 proteins were higher in both CaBP-28k and CaBP-9k/28k KO mice than in WT and CaBP-9k KO mice. These results suggest that the absence of CaBP-28k increases apoptotic signaling. We also investigated the expression of endoplasmic reticulum (ER) stress genes by Western blot analysis in calbindin KO mice. C/EBP homologous protein and immunoglobulin heavy chain-binding protein protein levels were elevated in CaBP-28k KO mice compared to WT mice. When immature mice were treated with 17β-estradiol (E2) or progesterone (P4) for 3 days, we found that the expressions of Bax and caspase 3 protein were increased by E2 treatment in WT and CaBP-9k KO mice, and by P4 treatment in CaBP-28k KO mice. These results indicate that CaBP-28k blocks the up-regulation of apoptosis-related genes and ER stress genes, implying that CaBP-28k may decrease the expression of genes involved in apoptosis and ER stress in murine uterine tissue.

Daphnoretin induces cell cycle arrest and apoptosis in human osteosarcoma (HOS) cells

In this study antiproliferation, cell cycle arrest and apoptosis induced by daphnoretin in human osteosarcoma (HOS) cells were investigated. Antiproliferative activity was measured with the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The IC(50) value of daphnoretin was 3.89 μM after 72 h treatment. Induction of apoptosis was evidenced by apoptotic body appearance and Annexin V-FITC/PI apoptosis detection kit. Flow cytometric analysis indicated daphnoretin arrested the cell cycle in the G2/M phase. Western-blot assay showed that the G2/M phase arrest was accompanied by down-regulation of cdc2, cyclin A and cyclin B1. Moreover, daphnoretin inhibited Bcl-2 expression and induced Bax expression to desintegrate the outer mitochondrial membrane and causing cytochrome c release. Mitochondrial cytochrome c release was associated with the activation of caspase-9 and caspase-3 cascade. Our results demonstrated that daphnoretin caused death of HOS cells by blocking cells successively in G2/M phases and activating the caspase-3 pathway.

SFE-CO2 extract from Typhonium giganteum Engl. tubers, induces apoptosis in human hepatoma SMMC-7721 cells involvement of a ROS-mediated mitochondrial pathway

Typhonium giganteum Engl. (BaiFuzi) is one of the herbs commonly used in traditional Chinese medicine against cancer. In our previous studies, 37 compounds were identified the SFE-CO₂ (supercritical fluid extraction with CO₂) extract by GC-MS, including the four major components [β-sitosterol (40.22%), campesterol (18.45%), n-hexadecanoic acid (9.52%) and (Z,Z)-9,12-octadecadienoic acid (8.15%)]. The anti-cancer mechanisms of the SFE-CO₂ extract from T. giganteum Engl. tubers have not been reported as yet. In this paper, the molecular mechanisms of the SFE-CO₂ extract-mediated apoptosis in SMMC-7721 cells were further examined. SFE-CO₂ extract inhibited the growth of SMMC-7721 cells in a time- and dose-dependent manner, arrested the cell cycle in the S phase and G2/M phase, and induced apoptosis. In addition, reactive oxygen species (ROS) increase, reduction of mitochondrial membrane potential, a rise in intracellular calcium levels were found in SMMC-7721 cells after treated with the extract. Western blot analysis showed that the extract caused down-regulation of Bcl-2 expression, and up-regulation of Bax expression. Moreover, caspase-3 and caspase-9 protease activity significantly increased in a dose-dependent manner. Collectively, our results showed that the SFE-CO₂ extract from T. giganteum Engl. tubers induces apoptosis in SMMC-7721 cells involving a ROS-mediated mitochondrial signalling pathway.

Chamaejasmine induces apoptosis in human lung adenocarcinoma A549 cells through a Ros-mediated mitochondrial pathway

In the present study, the anticancer activity of chamaejasmine towards A549 human lung adenocarcinoma cells was investigated. In order to explore the underlying mechanism of cell growth inhibition of chamaejasmine, cell cycle distribution, ROS generation, mitochondrial membrane potential (Δψ_m) disruption, and expression of cytochrome c, Bax, Bcl-2, caspase-3, caspase-9 and PARP were measured in A549 cells. Chamaejasmine inhibited the growth of A549 cells in a time and dose-dependent manner. The IC₅₀ value was 7.72 µM after 72 h treatment. Chamaejasmine arrested the cell cycle in the G2/M phase and induced apoptosis via a ROS-mediated mitochondria-dependent pathway. Western blot analysis showed that chamaejasmine inhibited Bcl-2 expression and induced Bax expression to desintegrate the outer mitochondrial membrane and causing cytochrome c release. Mitochondrial cytochrome c release was associated with the activation of caspase-9 and caspase-3 cascade, and active-caspase-3 was involved in PARP cleavage. All of these signal transduction pathways are involved in initiating apoptosis. To the best of our knowledge, this is the first report demonstrating the cytotoxic activity of chamaejasmine towards A549 in vitro.

Immunohistochemical studies on the proliferative marker Ki-67 and estrogen receptor alpha (ERα) in the uterus of neonatal and immature pigs following exposure to flutamide

The development of uterine glands is characterized by the proliferation of epithelial cells and by estrogen receptor alpha (ERα) expression in the nascent glandular epithelium. It is known that androgen receptors are present in the porcine uterus during prenatal development and the neonatal window, when adenogenesis occurs. Therefore, the objective of the study was to determine whether the effects of maternal or neonatal administration of the anti-androgen, flutamide, could entail changes in the presence of ERα and proliferation of uterine cells in neonatal and three-month-old pigs. Following prenatal flutamide exposure, morphological differences and the acceleration of uterus differentiation marked by ERα expression in epithelial crypts were observed in the neonatal piglets. In the three-month-old pig uterus, the proliferation of stromal cells was observed only after prenatal exposure to flutamide, whereas ERα staining was weaker. The neonatal administration of flutamide caused a significant decrease in the proliferation of the surface epithelium and diminished intensity of ERα staining in the stromal cells of the uterus of three-month-old pigs, which paralleled decreased estrogen levels in these animals. Overall, prenatal flutamide exposure promoted growth and development of the neonatal porcine uterus. Moreover, in three-month-old pigs, flutamide application during the neonatal period decreased surface epithelium proliferation and stromal ERα expression, which confirmed the importance of epithelial-stromal interactions in the adenogenesis.

Antimetastatic effects of Phyllanthus on human lung (A549) and breast (MCF-7) cancer cell lines

Background

Current chemotherapeutic drugs kill cancer cells mainly by inducing apoptosis. However, they become ineffective once cancer cell has the ability to metastasize, hence the poor prognosis and high mortality rate. Therefore, the purpose of this study was to evaluate the antimetastatic potential of Phyllanthus (P. niruri, P. urinaria, P. watsonii, and P. amarus) on lung and breast carcinoma cells.

Methodology/Principal Findings

Cytotoxicity of Phyllanthus plant extracts were first screened using the MTS reduction assay. They were shown to inhibit MCF-7 (breast carcinoma) and A549 (lung carcinoma) cells growth with IC₅₀ values ranging from 50–180 µg/ml and 65–470 µg/ml for methanolic and aqueous extracts respectively. In comparison, they have lower toxicity on normal cells with the cell viability percentage remaining above 50% when treated up to 1000 µg/ml for both extracts. After determining the non-toxic effective dose, several antimetastasis assays were carried out and Phyllanthus extracts were shown to effectively reduce invasion, migration, and adhesion of both MCF-7 and A549 cells in a dose-dependent manner, at concentrations ranging from 20–200 µg/ml for methanolic extracts and 50–500 µg/ml for aqueous extracts. This was followed by an evaluation of the possible modes of cell death that occurred along with the antimetastatic activity. Phyllanthus was shown to be capable of inducing apoptosis in conjunction with its antimetastastic action, with more than three fold increase of caspases-3 and -7, the presence of DNA-fragmentation and TUNEL-positive cells. The ability of Phyllanthus to exert antimetastatic activities is mostly associated to the presence of polyphenol compounds in its extracts.

Conclusions/Significance

The presence of polyphenol compounds in the Phyllanthus plant is critically important in the inhibition of the invasion, migration, and adhesion of cancer cells, along with the involvement of apoptosis induction. Hence, Phyllanthus could be a valuable candidate in the treatment of metastatic cancers.

Cajanol, a novel anticancer agent from Pigeonpea [Cajanus cajan (L.) Millsp.] roots, induces apoptosis in human breast cancer cells through a ROS-mediated mitochondrial pathway

Cajanol (5-hydroxy-3-(4-hydroxy-2-methoxyphenyl)-7-methoxychroman-4-one) is an isoflavanone from Pigeonpea [Cajanus cajan (L.) Millsp.] roots. As the most effective phytoalexin in pigeonpea, the cytotoxic activity of cajanol towards cancer cells has not been report as yet. In the present study, the anticancer activity of cajanol towards MCF-7 human breast cancer cells was investigated. In order to explore the underlying mechanism of cell growth inhibition of cajanol, cell cycle distribution, DNA fragmentation assay and morphological assessment of nuclear change, ROS generation, mitochondrial membrane potential (DeltaPsim) disruption, and expression of caspase-3 and caspase-9, Bax, Bcl-2, PARP and cytochrome c were measured in MCF-7 cells. Cajanol inhibited the growth of MCF-7 cells in a time and dose-dependent manner. The IC(50) value was 54.05 microM after 72 h treatment, 58.32 microM after 48 h; and 83.42 microM after 24h. Cajanol arrested the cell cycle in the G2/M phase and induced apoptosis via a ROS-mediated mitochondria-dependent pathway. Western blot analysis showed that cajanol inhibited Bcl-2 expression and induced Bax expression to desintegrate the outer mitochondrial membrane and causing cytochrome c release. Mitochondrial cytochrome c release was associated with the activation of caspase-9 and caspase-3 cascade, and active-caspase-3 was involved in PARP cleavage. All of these signal transduction pathways are involved in initiating apoptosis. To the best of our knowledge, this is the first report demonstrating the cytotoxic activity of cajanol towards cancer cells in vitro.

Apoptosis in the Porcine Uterine Endometrium During the Estrous Cycle, Early Pregnancy and Post Partum

The mammalian uterus changes dramatically during the estrous cycle, pregnancy, and involution post partum. Dynamic changes in the uterine endometrium are a type of homeostasis and proceed with proliferation and exclusion of cells. Homeostasis of the uterus is closely related to apoptosis involving various hormones and cytokines. The objective of the present study was to determine the morphological features and occurrence of apoptosis in the porcine endometrium during the estrous cycle, early pregnancy, and post partum. Cyclic changes in the morphology of the surface epithelium were observed during the estrous cycle. The heights of surface epithelia were significantly high on day 4 of the estrous cycle and the early pregnancy. The heights of the surface epithelium remained low from days 1 to 31 post partum. We then used terminal deoxynucleotidyl transferase-mediated biotinylated deoxyuridine triphosphate nick end-labeling (TUNEL) of the 3'-terminal of fragmented DNA, which is effective for detection of apoptosis in various tissues. We found that apoptosis in the porcine endometrium contributed to homeostasis of the endometrium during the estrous cycle through control of cell proliferation and exclusion. Conversely, apoptosis on days 4 and 8 of gestation before the implantation window depended on the plasma estrogen and progesterone levels; however, suppressive homeostasis of apoptosis occurred at the time of implantation on days 15, 18 and 21 of gestation. Our study is the first to demonstrate apoptotic cell death in the porcine endometrium directly by TUNEL method. The results strongly suggest that uterine homeostasis is mainly controlled by apoptosis during the estrous cycle and early pregnancy.

Expression of Bcl-2 and Ki-67 in Tamoxifen-Associated Endometrial Polyps: Comparison with Postmenopausal Polyps

BACKGROUND

The aim of this study was to evaluate the expression of Bcl-2 and Ki-67 in tamoxifen (TAM)-associated endometrial polyps and postmenopausal polyps.

MATERIAL AND METHODS

For this purpose, a retrospective analysis of paraffin-embedded specimens was carried out. Polyps of 20 postmenopausal and 14 TAM-treated patients, 11 simple endometrial hyperplasia, 10 atypical complex endometrial hyperplasia and 8 endometrial adenocarcinoma specimens were included in the study. Hematoxylin/eosin-stained sections were evaluated. Immunohistochemical staining was performed to investigate the expression of Bcl-2 protein and the Ki-67 proliferation index.

RESULTS

There was no statistically significant difference between the 5 groups with regard to Bcl- 2 staining (p > 0.05). However, Bcl-2 expression in TAM-associated polyps was higher (86%) than in the postmenopausal control group (80%). Positive Ki-67 was highest in the endometrial adenocarcinoma specimens, followed by the atypical complex endometrial hyperplasia group (p < 0.0001). Compared to these 2 groups, Ki- 67 expression was lower in TAM-associated polyps, but Ki-67 indexes were significantly higher in the TAM-associated group than in the control group (p < 0.0001).

CONCLUSION

Since TAM-associated polyps tend to have higher proliferation indexes and Ki-67 ratios than control groups, we suggest that they are likely to have a higher malignant potential.

Are endometrial polyps from pre-menopausal women similar to post-menopausal women? An immunohistochemical comparison of endometrial polyps from pre- and post-menopausal women

OBJECTIVE

Do endometrial polyps from pre- and post-menopausal women have similar immunohistochemical expression of oestrogen and progesterone receptors (ER, PR) and markers of cellular proliferation/apoptosis (Ki67 and Bcl-2).

DESIGN

Prospective cohort study. Non-parametric statistical analysis was used.

SETTING

Polyps recruited from women attending an out-patient hysteroscopy clinic in a UK district general hospital.

PATIENTS

Fourteen pre-menopausal and 16 post-menopausal women who presented with abnormal bleeding with endometrial polyps.

INTERVENTIONS

Immunohistochemical staining was performed on endometrial polyps.

MAIN OUTCOME MEASURES

Significant differences or correlations between hormone receptor expression (oestrogen and progesterone) and cell growth indices (Ki67 and Bcl-2).

RESULTS

Endometrial polyps from pre- and post-menopausal women had significant differences in their expression of hormone receptors and Ki67. However, polyps from both groups of women had similarly increased levels of Bcl-2, an inhibitor of apoptosis.

CONCLUSIONS

Pre- and post-menopausal polyps exhibit differing hormone receptor and proliferation markers, presumably a result of their hormonal milieu. However, both groups appear to have lost the usual control mechanisms for apoptotic regulation, this appears to be responsible for their growth.

An immunohistochemical comparison of endometrial polyps from postmenopausal women exposed and not exposed to HRT

OBJECTIVE

Our study set out to test the null hypothesis that oestrogen containing continuous combined hormone replacement therapy (HRT) would not affect the hormone receptor expression (oestrogen and progesterone receptors-ER, PR) or markers of cell proliferation/apoptosis (Ki67 and Bcl-2) in endometrial polyps from postmenopausal women exposed and not exposed to HRT.

DESIGN

Immunohistochemical staining for ER, PR, Ki67 and Bcl-2 was performed on polyps obtained from two groups of postmenopausal women.

SETTING

Polyps were obtained from postmenopausal women attending an outpatient hysteroscopy clinic in a district general hospital (Bradford Royal Infirmary, UK).

POPULATION

Twenty-five postmenopausal women presenting with abnormal bleeding subsequently diagnosed with endometrial polyps (16 from women not exposed to HRT, 9 from women exposed to HRT).

METHODS

Semiquantitative immunohistochemistry was performed.

MAIN OUTCOME MEASURES

Significant differences or correlations in either hormone receptor expression or markers of cell proliferation/apoptosis between the two groups of polyps.

RESULTS

There were no significant differences for hormone receptor expression (ER and PR) between endometrial polyps exposed and not exposed to HRT. Bcl-2 expression was higher than Ki67 in both groups, but polyps from HRT users had increased levels reflecting decreased apoptosis in these polyps.

CONCLUSIONS

HRT has no demonstrable effect on polyp ER and PR expression. However, HRT does appear to inhibit apoptosis and cell proliferation in endometrial polyps, which may affect polyp growth.

Does tamoxifen therapy affect the hormone receptor expression and cell proliferation indices of endometrial polyps? An immunohistochemical comparison of endometrial polyps from postmenopausal women exposed and not exposed to tamoxifen

OBJECTIVE

This study set out to test the null hypothesis that tamoxifen therapy would not affect the hormone receptor expression (oestrogen and progesterone receptors-ER and PR) or markers of cell proliferation/apoptosis (Ki67 and Bcl-2) of endometrial polyps from postmenopausal women exposed and not exposed to tamoxifen.

METHODS

Endometrial polyps were prospectively obtained from women presenting with abnormal bleeding attending an out-patient hysteroscopy clinic who subsequently underwent endometrial polypectomy (16 from postmenopausal women not exposed to tamoxifen, 9 from women exposed to tamoxifen). Immunohistochemical staining for ER, PR, Ki67 and Bcl-2 was performed on polyps from both groups of women. Non-parametric statistical analysis was used (Mann-Whitney and Spearmans rank correlation).

RESULTS

Endometrial polyps from tamoxifen users had significantly lower oestrogen receptor but increased progesterone receptor and Bcl-2 expression. There were no significant differences for proliferation markers (Ki67) between postmenopausal endometrial polyps exposed and not exposed to tamoxifen.

CONCLUSIONS

Tamoxifen has a significant affect on hormone receptor expression and markers of apoptosis in endometrial polyps. The results support the hypothesis that tamoxifen promotes polyp growth by inhibiting apoptosis. The mechanism for this does not appear to be oestrogen receptor mediated.

Nitric Oxide Induces Apoptosis in Bovine Luteal Cells

We previously showed in in vivo and in vitro studies that nitric oxide (NO) is engaged in luteolysis in cattle. Nitric oxide produced locally in the bovine corpus luteum (CL) inhibits progesterone (P4) synthesis and is suggested to be a component of the luteolytic cascade induced by uterine prostaglandin (PG) F2alpha. In the present study, the molecular mechanisms of NO action during structural luteolysis were studied in cultured bovine luteal cells (Days 15-17 of the estrous cycle). The effects of the NO donor (NONOate; 10(-4)M) on DNA fragmentation, cell viability, P4 production and caspase-3 activity were compared with those of PGF2alpha (10(-6)M). Moreover, mobilization of intracellular calcium [Ca2+]i and gene expressions of Fas-L, Fas, bcl-2, bax, and caspase-3 in the cells were determined by semi-quantitative RT-PCR after NONOate treatment. Caspase-3 activity was examined calorimetrically. Contrary to PGF2alpha NONOate decreased cell viability. DNA fragmentation after NONOate treatment increased by more than with PGF22alpha. NONOate increased mobilization of [Ca2+]i in the cells. Although the NO donor did not affect Fas-L and bcl-2 gene expression, it stimulated Fas and bax mRNA and caspase-3 expression. The ratio of bcl-2 to bax mRNA level decreased in the cells treated with NONOate. Moreover, NONOate stimulated caspase-3 activity more effectively than PGF2alpha. The overall results suggest that NO is a luteolytic factor that plays a crucial role in regulation of the estrous cycle in structural luteolysis by inducing apoptosis of luteal cells in cattle.

Apoptosis in human unfertilized oocytes after intracytoplasmic sperm injection

OBJECTIVE

To investigate the presence of programmed cell death in unfertilized oocytes after intracytoplasmic sperm injection (ICSI), assuming that previous apoptotic events could be correlated with the fertilization failure.

DESIGN

Comparison of the rate of DNA fragmentation in human oocytes at different stages of maturation soon after pick-up (control) and in unfertilized oocytes after ICSI treatment.

SETTING

In vitro fertilization (IVF) laboratory with extensive ICSI experience.

PATIENT(S)

Sixty-three patients undergoing assisted fertilization by ICSI.

INTERVENTION(S)

Terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP nick-end labeling (TUNEL) assay and anticaspase-3 cleaved immunoassay to detect apoptosis in control and ICSI-treated oocytes.

MAIN OUTCOME MEASURE(S)

Differences in the percentage of oocytes demonstrating DNA fragmentation between control oocytes and unfertilized ICSI treated oocytes at different stages of maturation.

RESULT(S)

The DNA fragmentation, by TUNEL assay, appeared in all the immature control oocytes, but only 37% of mature oocytes showed DNA fragmentation. This DNA fragmentation was observed in 88.8% of the oocytes unfertilized after ICSI; furthermore, DNA fragmentation appeared as well in the sperm injected into the cytoplasm.

CONCLUSION(S)

The study has shown DNA fragmentation in human oocytes unfertilized after ICSI. The evidence is confirmed as well in control oocytes, free from in vitro culture or manipulation stress. Caspase-3 immunoassay suggests the presence of apoptosis. The high percentage of oocytes demonstrating DNA fragmentation in the unfertilized oocytes could be correlated with fertilization failure.

Novel trends in follicular development, atresia and corpus luteum regression: a role for apoptosis

During ovarian follicular development in humans, only a limited number of follicles mature and ovulate. The vast majority of follicles stop developing after the formation of an antrum and then undergo atresia. The few that are selected to become ovulatory follicles are transformed into corpora lutea following ovulation. The lifespan of the corpus luteum is also limited. In each oestrus/menstrual cycle, corpora lutea regress and are eliminated by a progress called luteolysis. During atresia and luteolysis, granulosa and lutein cells undergo apoptosis. It is believed that there are many signal transduction pathways that control apoptosis in order to suppress full maturation of too many follicles and to protect the dominant follicle from the apoptotic process prior the ovulation. Such interplay between different factors, some of them produced in the ovary, may modulate apoptosis of corpus luteum cells, in order to preserve the function of the corpus luteum during pregnancy or to eliminate the old corpora lutea of the previous cycle. The present review reports a number of factors that regulate follicular atresia and corpus luteum regression, via apoptotic pathways. Elucidation of apoptotic mechanisms may lead to prevention of female infertility or other pathological conditions.

Relationship between DNA fragmentation and nuclear status of in vitro-matured porcine oocytes: role of cumulus cells

The present study was conducted to investigate the effects of the attachment of cumulus cells to oocytes and coculture with cumulus cells during maturation culture on the nuclear status and DNA fragmentation of porcine denuded oocytes (DOs). In the first experiment, cumulus cells were removed from cumulus–oocyte complexes (COCs) at 0, 8, 16, 24 or 32 h after the onset of maturation culture and the DOs were then cultured in their original droplets until 42 h of culture was reached. In the second experiment, all COCs were denuded before the onset of culture and the DOs were cocultured with their removed cumulus cells. The DOs were transferred into fresh medium at 0, 8, 16, 24 or 32 h after the onset of coculture with cumulus cells and then cultured until 42 h of culture was reached. After culture, DNA fragmentation and the nuclear status of oocytes were examined using the terminal deoxyribonucleotidyl transferase-mediated dUTP–digoxigenin nick end-labelling (TUNEL) method. When the DOs were returned to the same droplets after removal of the cumulus cells, the removal of the cumulus cells after 16 h of culture significantly decreased the proportion of oocytes remaining at the germinal vesicle (GV) stage. However, coculture treatment of DOs in the presence of their removed cumulus cells had no significant effects on the GV breakdown (GVBD) of oocytes. There were no significant differences in the proportion maturing to MII oocytes among the groups following removal of cumulus cells after the onset of maturation culture; however, DOs cocultured with cumulus cells until the end of maturation culture exhibited an increased maturation rate compared with DOs cocultured for 8 and 16 h. The total proportion of TUNEL-positive oocytes of oocytes remaining at the GV stage was higher than that of oocytes reaching other stages, irrespective of the removal of cumulus cells and coculture treatments. However, coculture for more than 16 h decreased the total proportion of TUNEL-positive oocytes. Our results indicate that the attachment of cumulus cells to oocytes may have a critical role for oocytes undergoing GVBD and that coculture with cumulus cells promotes the ability of oocytes to complete maturation. Moreover, coculture with cumulus cells may assist the oocyte to avoid undergoing DNA fragmentation.

Aspectos ultra-estruturais das vilosidades intestinais após o clampeamento do pedículo hepático de ratos

OBJETIVO: Estudar a ultra-estrutura das vilosidades intestinais de ratos após diferentes tempos de clampeamento total do pedículo hepático. MÉTODOS: Foram utilizados 40 ratos, machos, divididos em quatro grupos de 10 animais cada um. O grupo Sham não foi submetido a isquemia. Os grupos E1, E2 e E3 sofreram isquemia de 10, 20 e 30 minutos, respectivamente. Ao final do experimento, fragmentos do intestino delgado (íleo) foram retirados e processados para microscopia eletrônica de transmissão. RESULTADOS: Nos grupos E1 e E2 observou-se infiltração de leucócitos, dilatação vascular e áreas eletrolúcidas na lâmina própria das vilosidades. Já no grupo E3 observou-se desprendimento do revestimento epitelial, desintegração das microvilosidades e núcleos em apoptose. Na lâmina própria notamos áreas hemorrágicas, vasos sangüíneos e linfáticos dilatados e inúmeros leucócitos. CONCLUSÕES: o clampeamento do pedículo hepático hepático provoca congestão esplâncnica, tempo dependente, sendo que aos 30 minutos se nota desprendimento das células epiteliais, apoptose e hemorragia.