Overexpression of the Parkinson Disease Protein DJ-1 and its Regulator PTEN in Gestational Trophoblastic Disease:

Andrographolide induces protective autophagy and targeting DJ-1 triggers reactive oxygen species-induced cell death in pancreatic cancer

Background

Andrographolide (Andro), an extract of Andrographis paniculate (Burm.f.) Wall. ex Nees (Acanthaceae), possesses diverse biologically active properties. However, the precise mechanisms and effects of Andro on pancreatic cancer (PC) remain unclear.

Methods

The cytotoxic potential of Andro and underlying mechanism towards PC cells was investigated through in vitro experiments and a xenograft mouse model. PC cells were first subjected to varying concentrations of Andro. The reactive oxygen species (ROS) was assessed using flow cytometry and DCFH-DA staining. The apoptosis rate was detected by flow cytometry. Additionally, western blot was applied to evaluate the expression levels of cleaved-caspase-3, DJ-1, LC3-I, LC3-II, and p62. To further elucidate the involvement of ROS accumulation and autophagy, we employed N-acetylcysteine as a scavenger of ROS and 3-Methyladenine as an inhibitor of autophagy.

Results

Andro demonstrated potent anti-proliferative effects on PC cells and induced apoptosis, both in vitro and in vivo. The cytotoxicity of Andro on PC cells was counteracted by DJ-1 overexpression. The reduction in DJ-1 expression caused by Andro led to ROS accumulation, subsequently inhibiting the growth of PC cells. Furthermore, Andro stimulated cytoprotective autophagy, thus weakening the antitumor effect. Pharmacological blockade of autophagy further enhanced the antitumor efficacy of Andro.

Conclusion

Our study indicated that ROS accumulation induced by the DJ-1 reduction played a key role in Andro-mediated PC cell inhibition. Furthermore, the protective autophagy induced by the Andro in PC cells is a mechanism that needs to be addressed in future studies.

DJ‑1 is a new prognostic marker and predicts chemotherapy efficacy in colorectal cancer

Protein/nucleic acid deglycase DJ-1 (DJ-1) is a 20-kDa conserved protein, which belongs to the DJ-1/ThiJ/Pfp I protein superfamily. Immunohistochemistry was performed to investigate the expression of DJ-1 in a colorectal cancer (CRC) tissue microarray containing tumor and corresponding adjacent normal tissues. In the present study, DJ-1 expression was significantly upregulated in CRC cells and tissues, compared with that in normal colon cells and adjacent normal tissues, respectively. In addition, patients with high DJ-1 expression levels had a worse overall survival (OS) compared with patients with low expression levels. Multivariate Cox regression analysis revealed that high DJ-1 expression levels was an independent prognostic factor for patients with CRC. Moreover, DJ-1 was able to regulate the PI3K/Akt/p27/cyclin E and PI3K/Akt/mTOR signaling pathways to promote CRC cell growth and metastasis in vitro and in vivo. In addition, DJ-1 regulated the NF-κB/Snail signaling pathway to induce CRC cell epithelial-mesenchymal transition to promote migration and invasion. Notably, patients receiving LFP treatment (oxaliplatin, 5-FU and tetrahydrofolate) had an increased OS compared with patients who underwent only surgery and low DJ-1 expression levels. The findings from the present study suggest that DJ-1 may serve as a promising prognostic marker and predicts chemotherapy efficacy in patients with CRC.

In vitro fertilization and embryo transfer alter human placental function through trophoblasts in early pregnancy

The mechanism underlying the potential risk associated with in vitro fertilization and embryo transfer (IVF‑ET) has been previously investigated but remains to be fully elucidated. As the placenta is a critical organ that sustains and protects the fetus, this is an important area of research. The aim of the present study was to determine the difference in trophoblast cell function in the first trimester between naturally conceived pregnancies and pregnancies achieved via IVF‑ET therapy. A total of 20 placental villi in first trimester samples were obtained through fetal bud aspiration from patients undergoing IVF‑ET due to oviductal factors between January 2016 and August 2018. In addition, a further 20 placental villi were obtained from those who naturally conceived and had normal pregnancies but were undergoing artificial abortion; these patients were recruited as the controls. Reverse transcription‑quantitative (RT‑q)PCR and semi‑quantitative immunohistochemical methods were used to detect the mRNA and protein expression of α‑fetoprotein (AFP), vascular endothelial growth factor (VEGF), transferrin (TF), tubulin β1 class VI (TUBB1), metallothionein 1G (MT1G), BCL2, glial cells missing transcription factor 1 (GCM1), epidermal growth factor (EGF) receptor (EGFR), PTEN and leukocyte associated immunoglobulin like receptor 2 (LAIR2) in villi from both groups. Differentially expressed genes were analyzed using Search Tool for the Retrieval of Interacting Genes, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis was conducted. The RT‑qPCR data revealed that the mRNA expression levels of AFP, VEGF and TF were significantly higher in the IVF‑ET group than in the control group (P<0.05), and those of TUBB1, MT1G, BCL2, GCM1, EGFR, PTEN and LAIR2 were significantly lower (P<0.05). These gene products were expressed in the placental villus tissues, either in the cytoplasm, or in the membrane of syncytiotrophoblast and cytotrophoblast cells. The immunohistochemistry results were in line with those observed using RT‑qPCR. KEGG pathway analysis indicated that the trophoblast cell function of the IVF‑ET group in the first trimester was different from naturally conceived pregnancies with regard to proliferation, invasion, apoptosis and vascular development. The IVF‑ET process may trigger adaptive placental responses, and these compensatory mechanisms could be a risk for certain diseases later in life.

PARK7 regulates inflammation-induced pro-labour mediators in myometrial and amnion cells

Preterm birth is a prevalent cause of neonatal deaths worldwide. Inflammation has been implicated in spontaneous preterm birth involved in the processes of uterine contractility and membrane rupture. Parkinson protein 7 (PARK7) has been found to play an inflammatory role in non-gestational tissues. The aims of this study were to determine the expression of PARK7 in myometrium and fetal membranes with respect to term labour onset and to elucidate the effect of PARK7 silencing in primary myometrium and amnion cells on pro-inflammatory and pro-labour mediators. PARK7 mRNA expression was higher in term myometrium and fetal membranes from women in labour compared to non-labouring samples and in amnion from preterm deliveries with chorioamnionitis. In human primary myometrial cells transfected with PARK7 siRNA (siPARK7), there was a significant decrease in IL1B, TNF, fsl-1 and poly(I:C)-induced expression of pro-inflammatory cytokine IL6, chemokines (CXCL8, CCL2), adhesion molecule ICAM1, prostaglandin PGF_2α and its receptor PTGFR. Similarly, amnion cells transfected with siPARK7 displayed a decrease in IL1B-induced expression of IL6, CXCL8 and ICAM1. In myometrial cells transfected with siPARK7, there was a significant reduction of NF-κB RELA transcriptional activity when stimulated with fsl-1, flagellin and poly(I:C), but not with IL1B or TNF. Collectively, our novel data describe a role for PARK7 in regulating inflammation-induced pro-inflammatory and pro-labour mediators in human myometrial and amnion cells.

DJ-1 promotes survival of human colon cancer cells under hypoxia by modulating HIF-1α expression through the PI3K-AKT pathway

Background

Protein/nucleic acid deglycase (DJ-1) and hypoxia-inducible factor-1α (HIF-1α) play significant roles in the progression of various types of cancer and are associated with the phosphatidylinositol 3-kinase (PI3K) pathway. However, their functions in colorectal cancer (CRC) have not been identified. The aim of this study was to analyze the putative signaling pathway encompassing DJ-1, PI3K, and HIF-1α in a series of CRC tissues and cell lines.

Purpose

This study aimed at exploring the expression status of DJ-1 in colon cancer and its role in survival of cancer cell lines.

Methods

The expression and localization of DJ-1, PI3K-p110α, phosphorylated Akt (p-AKT), and HIF-1α were determined by immunohistochemistry in 73 resected CRC tissues. The effect of DJ-1 on cell activity was explored by in vitro knockdown and overexpression experiments in SW480 and HT-29 cells. The cells were treated with a PI3K inhibitor (LY294002 or wortmannin), and p-AKT and HIF-1α protein expression were then analyzed. Apoptosis was analyzed by flow cytometry. The expression levels of several HIF-1 target genes were assessed under hypoxic conditions by reverse transcription-PCR and Western blot. Xenograft tumor growth studies were conducted in DJ-1 knockdown or overexpression cells.

Results

High DJ-1 expression was found in 68.49% (50/73) of CRC tissues and associated with larger tumor size and advanced clinical stages. DJ-1 expression was positively associated with PI3K-p110α, p-AKT, and HIF-1α expression in CRC. HIF-1α and p-AKT protein levels were lower in SW480 and HT-29 cells with stable DJ-1 knockdown than in those with DJ-1 overexpression. PI3K inhibitors almost completely blocked DJ-1-induced AKT phosphorylation. However, the expression of HIF-1α was partially preserved after treatment with PI3K inhibitors. We also show that DJ-1 is necessary for the transcriptional ability of HIF-1α and CRC cell survival after hypoxic stress. Moreover, DJ-1 promoted the growth of established tumor xenografts in nude mice.

Conclusion

Our findings are the first to show that DJ-1 is overexpressed in CRC. We suggest a model in which DJ-1 mediates CRC cell survival by regulating the PI3K-AKT-HIF-1α pathway.

Effect of DJ-1 Downregulation on the Functions of the First Trimester Extravillous Trophoblasts

DJ-1 ( PARK7) has been reported to be causative gene of Parkinson disease and also an oncogene. A loss in DJ-1 function can lead to cell death in neurodegenerative disease, or a gain of it can cause unregulated cell survival in cancer, respectively. DJ-1 protein is known to be expressed mainly in trophoblastic cells in the placenta with increased expression in the first trimester compared to later in term. However, its role in trophoblast regulation remains unknown. This study aimed to investigate the effect of DJ-1 regulation on a first trimester extravillous trophoblast cell line, HTR-8/SVneo. The effect of DJ-1 downregulation induced by small-interfering RNA on cell apoptosis, migration, and the pathway to regulate the cell function was assessed. Data of this study showed that DJ-1 downregulation increased apoptosis and reduced migration by regulating matrix metalloproteinase 2 and matrix metalloproteinase 9 in HTR-8/SVneo cells under both ambient and oxidative stress. Changes in cell function were demonstrated to be at least partly dependent on the AKT/S6 kinase beta-1 (S6K1) pathway. In summary, DJ-1 might play a protective role in maintaining trophoblastic cell functions through the AKT/S6K1-based pathway.

FBI-1 Is Overexpressed in Gestational Trophoblastic Disease and Promotes Tumor Growth and Cell Aggressiveness of Choriocarcinoma via PI3K/Akt Signaling

Human placental trophoblasts can be considered pseudomalignant, with tightly controlled proliferation, apoptosis, and invasiveness. Gestational trophoblastic disease (GTD) represents a family of heterogeneous trophoblastic lesions with aberrant apoptotic and proliferative activities and dysregulation of cell signaling pathways. We characterize the oncogenic effects of factor that binds to the inducer of short transcripts of HIV-1 [FBI-1, alias POZ and Krüppel erythroid myeloid ontogenic factor (POKEMON)/ZBTB7A] in GTD and its role in promoting cell aggressiveness in vitro and tumor growth in vivo. IHC studies showed increased nuclear expression of FBI-1, including hydatidiform moles, choriocarcinoma (CCA), and placental site trophoblastic tumor, in GTD. In JAR and JEG-3 CCA cells, ectopic FBI-1 expression opposed apoptosis through repression of proapoptotic genes (eg, BAK1, FAS, and CASP8). FBI-1 overexpression also promoted Akt activation, as indicated by Akt-pS473 phosphorylation. FBI-1 overexpression promoted mobility and invasiveness of JEG-3 and JAR, but not in the presence of the phosphoinositide 3-kinase inhibitor LY294002. These findings suggest that FBI-1 could promote cell migration and invasion via phosphoinositide 3-kinase/Akt signaling. In vivo, nude mice injected with CCA cells with stable FBI-1 knockdown demonstrated reduced tumor growth compared with that in control groups. These findings suggest that FBI-1 is clinically associated with the progression of, and may be a therapeutic target in, GTD, owing to its diverse oncogenic effects on dysregulated trophoblasts.