TRIM27 regulates the expression of PDCD4 by the ubiquitin­proteasome pathway in ovarian and endometrial cancer cells.

Programmed cell death 4 (PDCD4) is regarded as an important tumor suppressor that is lowly expressed or deleted in numerous human types of cancer, including ovarian and endometrial cancer. Tripartite motif­containing 27 (TRIM27) is closely related to the occurrence and development of tumors and is highly expressed in numerous types of cancer such as ovarian and endometrial cancer. PDCD4 can be degraded through ubiquitination, while TRIM27 has the E3 ubiquitin ligase activity. However, whether TRIM27 may regulate the expression of PDCD4 by ubiquitination effect remains unclear. In the present study, the expression of PDCD4 and TRIM27 in different ovarian and endometrial cancer cell lines was detected by reverse transcription­quantitative PCR (RT­qPCR), western blotting and immunocytochemistry. The impact of TRIM27 overexpression and knockdown on PDCD4 expression and the effective mechanism of TRIM27 regulating PDCD4 expression were also investigated in vitro by RT­qPCR, western blotting, co­immunoprecipitation assay, Transwell migration and Matrigel invasion assays. The results showed that the expression of TRIM27 and PDCD4 had a negative association at the protein level, and the distribution of TRIM27 and PDCD4 proteins had a phenomenon of co­localization in different ovarian and endometrial cancer cell lines. TRIM27 promoted the degradation of PDCD4 through the ubiquitin­proteasome pathway. To sum up, TRIM27 could increase the migration and invasion of ovarian and endometrial cancer cells by promoting the ubiquitination and degradation of PDCD4. The present findings may provide a new target for the treatment of ovarian and endometrial cancer.

IL-37bΔ1-45 suppresses the migration and invasion of endometrial cancer cells by targeting the Rac1/NF-κB/MMP2 signal pathway.

Endometrial carcinoma is one of the most common malignancies in the female reproductive system. Interleukin-37 (IL-37) is a newly discovered anti-inflammatory factor belonging to the IL-1 family. IL-37 has five different isoforms, and IL-37b is the most biologically functional subtype. In recent years, the protective roles of IL-37 in different cancers, including lung and liver cancers, have been successively reported. IL-37 also plays an important role in some gynecological diseases such as endometriosis, adenomyosis, and cervical cancer. However, the role and mechanism of IL-37b, especially the mature form of IL-37b, in endometrial carcinoma have not been elucidated. The present study demonstrated that IL-37 protein was downregulated in endometrial carcinoma cells compared with the control endometrium. IL-37b did not affect the proliferation and colony-forming ability of endometrial cancer cells. A mature form of IL-37b (IL-37bΔ1-45) effectively suppressed the migration and invasion of endometrial cancer cells by decreasing the expression of matrix metalloproteinase 2 (MMP2) via Rac1/NF-κB signal pathway. However, it did not affect epithelial-mesenchymal transition (EMT) or filamentous actin (F-actin) depolymerization of endometrial cancer cells. IL-37bΔ1-45 attenuated tumor metastasis in a peritoneal metastatic xenograft model of endometrial cancer. To sum up, these results suggested IL-37b could be involved in the pathogenesis of endometrial carcinoma and provide a novel target for the diagnosis and treatment of endometrial carcinoma.

TIPE2 inhibits the migration and invasion of endometrial cells by targeting ß-catenin to reverse epithelial-mesenchymal transition.

STUDY QUESTION: Do changes in tumor necrosis factor-α-induced protein 8 (TNFAIP8)-like 2 (TIPE2) levels in endometrium of patients with adenomyosis alter the proliferation, migration and invasion ability of endometrial cells? SUMMARY ANSWER: TIPE2 expression levels were low in eutopic and ectopic endometrium of adenomyosis patients, and TIPE2 inhibited the migration and invasion of endometrial cells, mainly by targeting ß-catenin, to reverse the epithelial-mesenchymal transition (EMT). WHAT IS KNOWN ALREADY: Adenomyosis is a benign disease, but it has some pathophysiological characteristics similar to the malignant tumor. TIPE2 is a novel negative immune regulatory molecule, and it also participates in the development of malignant tumors. STUDY DESIGN, SIZE, DURATION: Control endometrium (n = 48 women with non-endometrial diseases) and eutopic/ectopic endometrium from patients with adenomyosis (n = 50), human endometrial cancer cell lines, and primary endometrial cells from the eutopic endometrium of adenomyosis patients were used in the study. PARTICIPANTS/MATERIALS, SETTING, METHODS: The expression level of TIPE2 mRNA and protein in the eutopic/ectopic endometrial tissues of adenomyosis patients and control endometrium was determined by quantitative RT-PCR (qRT-PCR), western blot and immunohistochemistry. The effects of TIPE2 overexpression and knockdown on the proliferation, migration and invasion of endometrial cell lines and primary adenomyotic endometrial cells were determined using a cell counting kit-8, 5-ethynyl-2'-deoxyuridine assay, colony-forming assay, transwell migration assay and matrigel invasion assay. The expression of EMT-related markers and signal molecules was detected by western blot. The interaction between TIPE2 and ß-catenin was detected by co-immunoprecipitation and laser confocal microscopy. MAIN RESULTS AND THE ROLE OF CHANCE: The mRNA and protein expression levels of TIPE2 in the eutopic and ectopic endometrial tissues of adenomyosis patients were significantly downregulated compared with the control endometrium (P Ë‚ 0.01). TIPE2 could bind to ß-catenin and inhibit the nuclear translocation of ß-catenin, downregulate the expression of stromal cell markers, upregulate the expression of glandular epithelial cell markers, decrease the occurrence of epithelial-mesenchymal transition (EMT) and suppress the migration and invasion of endometrial cells (P Ë‚ 0.01). LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: In this study, the experiments were performed only in eutopic and ectopic endometrial tissues, endometrial cancer cell lines and primary adenomyotic endometrial cells. A mouse model of adenomyosis will be constructed to detect the effects of TIPE2 in vivo. WIDER IMPLICATIONS OF THE FINDINGS: These results suggest that TIPE2 is involved in the development of adenomyosis, which provides a potential new diagnostic and therapeutic strategy for the treatment of adenomyosis. STUDY FUNDINGS/COMPETING INTEREST(S): This present study was supported by grants from the National Natural Science Foundation of China (81471437, 81771554), Natural Science Foundation of Shandong (ZR2018MH013), Science and technology development plan provided by Health and Family Planning Committee in Shandong (2014-25). The authors declare that they have no conflicts of interest.

Downregulation of PDCD4 induced by progesterone is mediated by the PI3K/AKT signaling pathway in human endometrial cancer cells.

Programmed cell death 4 (PDCD4) has been identified as a tumor­suppressor gene that inhibits neoplastic transformation, tumor progression, and protein translation. It has been reported that multiple factors participate in the regulation of PDCD4 mRNA and protein. The endometrium is regulated by changing concentrations of ovarian hormones, such as estrogen and progesterone, and shows periodical changes. However, whether ovarian hormones regulate PDCD4 expression remains unclear. This study aimed to explore the effect and mechanism of estrogen or progesterone on PDCD4 mRNA and protein expression in human endometrial cancer cells. The expression of PDCD4 mRNA and protein in Ishikawa and HEC­1­A cells was detected by quantitative real­time PCR and western blot analysis. The signaling pathway­related proteins were detected by western blot analysis. The results showed that PDCD4 mRNA levels exhibited no significant changes after treatment with estrogen or progesterone in both Ishikawa and HEC­1­A cell lines. Estrogen also had no obvious effect on PDCD4 protein expression. However, progesterone effectively decreased the expression of PDCD4 protein and the PI3K/AKT pathway may be involved in the downregulation of PDCD4 protein induced by progesterone. These results suggest that the downregulation of PDCD4 induced by progesterone affects the therapeutic efficacy of progesterone in human endometrial cancer or endometriosis, which may have important implications for progesterone treatment in the clinic.

PDCD4 suppresses proliferation, migration, and invasion of endometrial cells by inhibiting autophagy and NF-κB/MMP2/MMP9 signal pathway.

Endometriosis (EM) is a kind of estrogen-dependent disease in reproductive-age women. Ovarian EM is the most common type. Although EM is a benign disease, it shares many similar features with cancers. Programmed cell death 4 (PDCD4), a newly identified tumor suppressor, plays an important role in inhibiting tumorigenesis and tumor progression at the transcriptional and translational levels. To explore the roles of PDCD4 in EM, we detected the expression of PDCD4 in control endometrium and eutopic/ectopic endometrium of ovarian EM patients, and analyzed the effects of PDCD4 on the biological behaviors of endometrial cell lines and primary endometrial cells. The results demonstrated that PDCD4 was downregulated in eutopic and ectopic endometrium of EM patients compared with control endometrium. PDCD4 effectively inhibited the proliferation and colony-forming ability of endometrial cells maybe by inhibiting cell autophagy. In addition, PDCD4 also suppressed the migration and invasion ability of endometrial cells, the mechanism may be related to NF-κB/MMP2/MMP9 signal pathway. Taken together, these results suggest that PDCD4 could be involved in the pathogenesis of EM, and provide a novel approach to target the aberrant PDCD4 expression in EM.

Expression of tumor suppressor programmed cell death 4 in endometrioid endometrial carcinomas and clinicopathological significance.

Programmed cell death 4 (PDCD4), as a novel tumor suppressor, serves important roles in the pathogenesis of tumors. The expression of PDCD4 is downregulated or lost in various human tumors. However, the expression of PDCD4 in endometrial cancer and the clinicopathological significance remain unclear. The aim of the present study was to investigate the expression of PDCD4 in endometrioid endometrial carcinoma (EEC) and the association with clinicopathological parameters. The expression of PDCD4 in EEC tissues and control endometrium was detected by reverse transcription-quantitative polymerase chain reaction, western blotting and immunohistochemistry. PDCD4 expression was also investigated in control endometrial glandular epithelial cells and the endometrial cancer KLE cell line by immunocytochemistry, and the association between PDCD4 expression and clinicopathological parameters of patients with EEC was analyzed. The results demonstrated that PDCD4-positive staining was mainly located in the cytoplasm of endometrial glandular epithelial cells and EEC cells. The staining index of PDCD4 in the proliferative phase was significantly increased compared with that in the secretory phase of control endometrium (P<0.001). There was significantly decreased PDCD4 expression in grade (G) 2/3 EEC tissues compared with the proliferative phase of control endometrium (P<0.001). PDCD4 expression was significantly associated with tumor grade. The PDCD4 levels in G1 EEC tissues were higher compared with the G2/3 EEC group (P<0.01). The results indicated that PDCD4 is associated with the histological grade of EEC, and that PDCD4 may be a valuable indicator of the degree of tumor malignancy in patients with EEC.

The Expression of PDCD4 in Patients With Missed Abortion and Its Clinical Significance.

Missed abortion is a special form of spontaneous abortion and its incidence shows a rising trend. Immunological factor is one of the most common reasons. Tumor suppressor gene programmed cell death 4 ( PDCD4) also participates in some immune-mediated inflammation, such as atherosclerosis, and so on, but the role of PDCD4 in missed abortion remains unclear. Here, the expression of PDCD4 was detected in decidual and chorionic tissues, as well as peripheral blood mononuclear cells from patients with missed abortion and healthy controls using quantitative real-time polymerase chain reaction (qRT-PCR), Western blot, and immunohistochemistry. The expression of cytokines was also detected in decidual tissues using qRT-PCR. The levels of serum estradiol and progesterone were measured by radioimmunoassay. In addition, the correlations of PDCD4 expression with cytokines and hormones were analyzed. The results demonstrated that PDCD4 expression was reduced in decidual tissues from the missed abortion group compared with the control group. The levels of tumor necrosis factor α were significantly higher in decidual tissues of missed abortion patients than those in normal controls. We also found serum estradiol and progesterone levels were significantly lower in the missed abortion group than those in the control group, and serum progesterone level was inversely related to PDCD4 messenger RNA level. The data suggested that reduced PDCD4 expression may be involved in the occurrence of missed abortion. This may facilitate the potential development of novel diagnostic and therapeutic strategies for the treatment of missed abortion.

The decreased expression of TIPE2 protein in the decidua of patients with missed abortion and possible significance.

BACKGROUND: Missed abortion is a common occurrence for otherwise healthy women. Immunological factor is one of the most important reasons. Tumor necrosis factor-α-induced protein-8 like-2 (TIPE2) is a novel negative immune regulator related to several human diseases. However, the expression level and clinical significance of TIPE2 in missed abortion remain unclear. METHODS: The expression of TIPE2 mRNA and protein in decidua and chorion from 36 missed abortion patients and 36 healthy controls was detected using quantitative real-time PCR, western blot and immunohistochemistry. In addition, serum TNF-ɑ and IL-10 levels were measured using flow cytometry. Serum estradiol and progesterone levels were measured by radioimmunoassay test. The correlations of TIPE2 protein levels with TNF-ɑ, IL-10, estradiol and progesterone were further analyzed. RESULTS: TIPE2 protein levels were significantly lower in decidual tissues of missed abortion patients than those in healthy controls. The patients with missed abortion had significantly higher levels of serum TNF-ɑ, and lower levels of serum IL-10, estradiol and progesterone compared with healthy controls. The TIPE2 protein levels were positively related to serum IL-10 levels. CONCLUSION: Our data indicate TIPE2 could play important roles in maintaining the maternal-fetal tolerance and decreased TIPE2 expression in the decidua may be related to the development of missed abortion.

The reduced PDCD5 protein is correlated with the degree of tumor differentiation in endometrioid endometrial carcinoma.

Endometrial cancer is one of the most common malignancies in the female genital tract. Programmed cell death 5 (PDCD5) is a newly identified apoptosis related gene and plays an important role in the development of some human tumors. However, the expression and clinical significance of PDCD5 in endometrial cancer have not been fully elucidated. Here, we evaluated the expression of PDCD5 in endometrioid endometrial carcinoma and control endometrium by qRT-PCR, western blot and immunohistochemistry, and analyzed the associations of PDCD5 expression with clinicopathological parameters of patients. In addition, we detected the expression of PDCD5 in control endometrial glandular epithelial cells and endometrioid endometrial carcinoma-derived cell line KLE by immunocytochemistry. The results showed that PDCD5 protein mainly expressed in the cytoplasm of glandular epithelial cells and endometrial carcinoma cells, and there was a low level of PDCD5 expression in the nuclei of the above cells. Furthermore, PDCD5 protein level was significantly lower in endometrial carcinoma samples than that in control endometrium. The decreased PDCD5 expression was correlated with the tumor differentiation degree. It is clear that PDCD5 protein expression was lower in middle and low differentiated endometrial carcinoma compared with control endometrium and high differentiated endometrial carcinoma. However, there were no significant differences of PDCD5 expression between the proliferative phase and the secretory phase of control endometrium, as well as between high differentiated endometrial carcinoma and controls. The results were verified in control glandular epithelial cells and KLE cells by immunocytochemistry. Therefore, PDCD5 may play a key role in the pathogenesis of endometrial cancer and may be a novel target for diagnosis and treatment of endometrial cancer.

Epac1 knockdown inhibits the proliferation of ovarian cancer cells by inactivating AKT/Cyclin D1/CDK4 pathway in vitro and in vivo.

Ovarian cancer is the leading cause of death among gynecological malignancies, and high grade serous ovarian carcinoma is the most common and most aggressive subtype. Recently, it was demonstrated that cAMP mediates protein kinase A-independent effects through Epac (exchange protein directly activated by cAMP) proteins. Epac proteins, including Epac1 and Epac2, are implicated in several diverse cellular responses, such as insulin secretion, exocytosis, cellular calcium handling and formation of cell-cell junctions. Several reports document that Epac1 could play vital roles in promoting proliferation, invasion and migration of some cancer cells. However, the expression levels and roles of Epac1 in ovarian cancer have not been investigated. In the present study, we detected the expression levels of Epac1 mRNA and protein in three kinds of ovarian cancer cells SKOV3, OVCAR3 and CAOV3. Furthermore, the effect of Epac1 knockdown on the proliferation and apoptosis of SKOV3 and OVCAR3 cells was evaluated in vitro and in vivo. The results showed that there was higher expression of Epac1 mRNA and protein in SKOV3 and OVCAR3 cells. Epac1 knockdown inhibited the proliferation of SKOV3 and OVCAR3 cells in vitro and in vivo. Decreased proliferation may be due to downregulation of Epac1-induced G1 phase arrest by inactivating the AKT/Cyclin D1/CDK4 pathway, but not to alterations in the MAPK pathway or to apoptosis. Taken together, our data provide new insight into the essential role of Epac1 in regulating growth of ovarian cancer cells and suggest that Epac1 might represent an attractive therapeutic target for treatment of ovarian cancer.

Downregulation of TRIM27 expression inhibits the proliferation of ovarian cancer cells in vitro and in vivo.

TRIM27 (tripartite motif-containing 27) was originally identified as a fusion partner with the RET (REarranged during transfection) proto-oncogene and is highly expressed in various tumor cells and tissues. However, the level of expression and function of TRIM27 in ovarian cancer remain unclear. Here we have measured the expression of TRIM27 in normal ovarian and fallopian tube epithelial cells and in ovarian serous carcinoma cells and correlated TRIM27 expression with clinical and pathological parameters. In addition, we detected the effect of TRIM27 knockdown on proliferation of ovarian cancer cells in cell culture and xenografts. The results demonstrated that TRIM27 was highly expressed in ovarian serous carcinoma cells, and TRIM27 expression was significantly correlated with metastasis and FIGO stage in ovarian serous carcinoma patients. Downregulation of TRIM27 expression suppressed the proliferation of ovarian cancer cells in cell culture and inhibited the growth of xenografts in nude mice. TRIM27 knockdown induced cell cycle arrest and apoptosis in ovarian cancer cells by upregulating the expression of p-P38 and downregulating the expression of p-AKT. Thus the present study suggests that TRIM27 could have important roles as an oncogene during the development of ovarian cancer and could serve as a diagnostic and therapeutic target.

Pretreatment with wortmannin alleviates lipopolysaccharide/d-galactosamine-induced acute liver injury.

Intestinal endotoxemia-induced liver injury is a common clinical disease which leads to liver failure and death. Wortmannin, an inhibitor of phosphatidylinositol 3-kinase, could be used for suppressing autophagy in vitro and in vivo. Autophagy is an evolutionarily conserved and lysosome dependent protein degradation pathway, which participates in various physiological and pathological processes. The present study aims to explore the effect of pretreatment with wortmannin on acute liver injury and the autophagy in acute liver injury. We demonstrated that wortmannin could downregulate the expression of phosphorylated extracellular regulated protein kinase and p65, decrease the production and release of hepatic inflammatory cytokines, and then reduce hepatocytes apoptosis and necrosis. More importantly, we found that autophagy was induced to increase in LPS/D-GalN-induced acute liver injury, and pretreatment with wortmannin could effectively inhibit increased autophagy in acute liver injury. In conclusion, these results indicate that wortmannin plays a protective role in LPS/D-GalN induced hepatocytotoxity maybe by inhibiting autophagy and could be acted as a target for the treatment of acute liver injury.

The expression of a novel anti-inflammatory cytokine IL-35 and its possible significance in childhood asthma.

Interleukin-35 (IL-35) is a novel anti-inflammatory cytokine and has been shown to play an important role in maintaining immune homeostasis. However, the effect of IL-35 on human asthma remains unclear. The present study is to investigate the expression and significance of IL-35 in childhood asthma. Forty-one asthmatic children and forty-two healthy controls were recruited in Qilu Children's Hospital of Shandong University. Serum total immunoglobulin E level was measured by radioimmunosorbent test. Peripheral blood eosinophils were counted using BC-5800 Automatic Blood Cell Analyzer. IL-35 mRNA in peripheral blood mononuclear cells was detected by quantitative real-time polymerase chain reaction. Serum IL-35, IL-4 and interferon-γ levels were measured using enzyme-linked immunosorbent assay. The correlations among the above indexes were also analyzed using Pearson's method. Our results showed that serum total IgE, eosinophil count and serum IL-4 were significantly increased in asthmatic children compared with control children, and serum IFN-γ level in asthmatic patients was obviously lower than that in healthy controls. We also found that there was an obviously positive correlation between serum IgE and IL-4 levels in asthmatic patients. In addition, significantly negative correlation was found between serum total IgE and IFN-γ levels. More importantly, we found that the expression of IL-35 mRNA and protein was both down-regulated in asthmatic children, and serum IL-35 level was inversely related to serum IL-4 level. Moreover, significantly positive correlation was also found between serum IL-35 and IFN-γ levels. The results suggest that the decreased expression of IL-35 could be involved in the pathogenesis of childhood asthma.

Effects of varying tissue sizes on the efficiency of baboon ovarian tissue vitrification.

OBJECTIVE: The aim of this study was to detect the effects of varying tissue sizes on the efficiency of baboon ovarian tissue vitrification. STUDY DESIGN: The percentages of morphologically normal primordial follicles and the follicles expressing bax protein in ovarian tissues after vitrification-warming were measured. Besides, the 17-ß estradiol levels in the culture supernatants were measured. RESULTS: The percentages of morphologically normal primordial follicles in vitrified-warmed ovarian tissues slicing in 0.5-1.5mm in length and wide, and 1.0mm in thickness were significantly higher than those slicing in 2.0mm in length and wide, and 1.0mm in thickness. Moreover, the follicles expressing bax protein in vitrified-warmed ovarian tissues slicing in 0.5-1.5mm in length and wide, and 1.0mm in thickness were significantly lower than those slicing in 2.0mm in length and wide, and 1.0mm in thickness. The 17-ß estradiol levels in the culture supernatants slicing in 1.0-1.5mm in length and wide, and 1.0mm in thickness were significantly higher than those slicing in 0.5mm or 2.0mm in length and wide, and 1.0mm in thickness. CONCLUSIONS: Cortex piece slicing in 1.0-1.5mm in length and wide, and 1.0mm in thickness is suitable for baboon ovarian vitrification.

The long-term effects of superovulation on fertility and sexual behavior of male offspring in mice.

PURPOSE: To evaluate the long-term effects of superovulation on fertility and sexual behavior of male offspring in mice. METHOD: The mice were superovaluted, and the fertility of male offspring (F1 generation and F2 generation) were evaluated in terms of the percentage of plugs and pregnancies, serum testosterone concentrations, and sperm motility. Furthermore, the sexual behavior of male offspring and sex ratio (F1 generation and F2 generation) were measured. RESULTS: There were no significant differences in the percentage of plug and pregnancies, serum testosterone concentrations, sperm motilities and sex ratio between the offspring in naturally conceived group and superovulation groups (both F1 generation and F2 generation). The sperm hyperactivity at 90 min after incubation of F1 generation in naturally conceived group were higher than that of F1 generation in superovulation group, but the differences did not reach statistical significance. The offspring produced by superovaluted oocytes (both F1 generation and F2 generation) did not exhibit significant alterations in sexual behavior. CONCLUSIONS: No significant alterations were found in fertility and sexual behavior of male offspring in mice produced by superovaluted oocytes compared with those of naturally conceived offspring.

A preliminary study on the construction of double suicide gene delivery vectors by mesenchymal stem cells and the in vitro inhibitory effects on SKOV3 cells.

The aim of the present study was to investigate the efficacy of using human umbilical cord blood-derived mesenchymal stem cells (hUCB-MSCs) as gene delivery vectors in the treatment of ovarian cancer. Lentivectors overexpressing cytosine deaminase (CD) and herpes simplex virus thymidine kinase (HSV-tk) (pGC-FU-CD-TK) were constructed, and confirmed by enzyme digestion, DNA sequence and western blotting. Quantitative PCR (PCR) was used to verify the overexpression of the fusion gene (CD and HSV-tk). SKOV3 cells were co-cultured with MSCs/tk+CD+ at a 1:1 ratio, and were then treated with the prodrugs (GCV) and/or 5-fluorocytosine (5-FC) at different concentrations, and the cytotoxic effects were evaluated using MTT assay and flow cytometry. DNA sequencing demonstrated that the sequence of HSV-tk and CD genes were consistent with the objective sequence and western blotting verified that the constructed lentivector could produce the HSV-tk/CD gene. The packed titer was 2.00e+8 TU/ml. The pGC-FU-CD-TK could be stably transferred to hUCB­MSCs, and the infection efficiency was almost 80%. RT-PCR demonstrated that the expression levels of the HSV-tk/CD fusion gene in MSCs/tk+CD+ group was 75 times that in the negative control (P<0.05). Compared with GCV or 5-FC alone, the growth inhibition rate (GIR) was significantly higher in the combined treatment (F=85.35, P<0.05). The reconstructed MSCs/tk+CD+ vectors were capable of slowing down the growth of human SKOV3 cells in the presence of prodrugs in vitro. The use of combination chemotherapy exhibited a more significant inhibitory effect than using a single prodrug.

The inhibitory action of PDCD4 in lipopolysaccharide/D-galactosamine-induced acute liver injury.

Programmed cell death 4 (PDCD4) acts as a tumor suppressor gene, which suppresses tumor growth, infiltration and metastasis. Our previous studies demonstrated that PDCD4 had an important role in the development of ovarian cancer and glioma. Recent studies show that PDCD4 is also involved in various inflammatory diseases. However, its exact effect on inflammation remains unclear. In our current study, we explored the role of PDCD4 in acute liver injury induced by lipopolysaccharide (LPS) and D-galactosamine (D-GalN) using wild-type (WT) mice and PDCD4-deficient mice. Our results showed that liver-to-body weight ratios, as well as serum aspartate transaminase (AST) and alanine transaminase (ALT) levels were significantly increased in PDCD4-deficient mice than WT mice. Histological examination, immunohistochemical and TUNEL analysis revealed PDCD4-deficient mice had more necrotic and apoptotic hepatocytes, inflammatory cells infiltration and liver internal hemorrhage than WT mice. In addition, some inflammatory cytokines such as tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6) in the serum and liver tissues were also significantly increased in PDCD4-deficient mice. More importantly, we found that the aggravation of liver tissue injury in PDCD4-deficient mice was due to excessive mitogen-activated protein kinase and NF-κB activation, which induced the release of more inflammatory factors, and consequently resulted in higher levels of hepatocyte necrosis and apoptosis. These results indicate that PDCD4 has a protective role in LPS/D-GalN-induced acute liver injury. This finding may present new opportunities for PDCD4 to be explored as a therapeutic target in acute liver injury.

Clinical and prognostic significance of lost or decreased PDCD5 expression in human epithelial ovarian carcinomas.

Programmed cell death 5 (PDCD5) is a novel apoptosis-promoting protein. Although the decreased expression of PDCD5 has been recently found in a few types of human tumors, the status and significance of PDCD5 in ovarian cancer has not been evaluated. In the present study, we detected PDCD5 expression in 20 normal human ovaries and 26 serous cystadenomas and 41 serous cystadenocarcinomas by RT-PCR, Western blotting and immunohistochemistry, and analyzed the relationship between PDCD5 expression and clinicopathological data or patient survival. PDCD5 was expressed in all normal ovaries and serous cystadenomas, 80% (16/20) of normal ovarian tissues and 76.9% (20/26) of serous cystadenomas with moderate or strong PDCD5 protein expression. In contrast, 22% (9/41) of serous cystadenocarcinomas had no detectable PDCD5 protein expression and 46.3% (19/41) exhibited weak PDCD5 expression. The overall expression of PDCD5 in serous cystadenocarcinoma was significantly lower compared with normal ovarian tissues or serous cystadenomas (p<0.01). Furthermore, lost or decreased PDCD5 expression in serous cystadenocarcinomas was associated significantly with FIGO stage (p<0.05) and poorer disease-specific survival of patients (p<0.05). In conclusion, our data suggest that lost or reduced PDCD5 expression may contribute to the pathogenesis of human serous cystadenocarcinomas.

PDCD4 inhibits the malignant phenotype of ovarian cancer cells.

Programmed cell death 4 (PDCD4) is a newly identified tumor suppressor that can inhibit activator protein (AP)-1 activation and protein translation. Our previous studies indicate that lost or reduced PDCD4 expression is associated with the progression of ovarian carcinoma. However, direct evidence that PDCD4 inhibits malignant phenotype of human cancer cells is limited. In the present study, we found that PDCD4 expression in ovarian cancer cell lines (SKOV3, 3AO, and CAOV3) inhibited significantly their proliferation and cell cycle progression, and induced apoptosis. More importantly, up-regulation of PDCD4 expression decreased the colony-forming capacity of ovarian cancer cells in vitro and tumorigenic capacity in mice. These results demonstrate that PDCD4 can suppress the malignant phenotype of ovarian cancer cells, and may represent a novel therapeutic target for the treatment of ovarian cancer.

Expression and prognostic significance of PDCD4 in human epithelial ovarian carcinoma.

BACKGROUND: Programmed cell death 4 (PDCD4) is a newly discovered tumor suppressor. The aim of this study was to investigate the expression and prognostic significance of PDCD4 in epithelial ovarian cancer. MATERIALS AND METHODS: PDCD4 expression in 20 normal human ovaries and 69 serous ovarian tumors was examined by RT-PCR and immunohistochemistry. The relationships between PDCD4 expression, clinicopathological data and patient survival were evaluated. RESULTS: PDCD4 expression was found to be lost or significantly lower in serous cystadenocarcinomas compared with that in normal ovaries and serous cystadenomas (p<0.05). The loss or reduction of PDCD4 expression in serous cystadenocarcinomas was significantly associated with higher pathological grade (p=0.0118) and poorer disease-specific survival of patients (p=0.0011). Multivariant Cox regression analysis revealed that PDCD4 expression was an independent prognostic factor for serous cystadenocarcinoma. CONCLUSION: Lost or reduced PDCD4 expression is associated with the progression of serous cystadenocarcinomas and may serve as an important prognostic marker.