DJ-1 is involved in the multidrug resistance of SGC7901 gastric cancer cells through PTEN/PI3K/Akt/Nrf2 pathway

Diallyl disulfide antagonizes DJ-1 mediated proliferation, epithelial-mesenchymal transition, and chemoresistance in gastric cancer cells

Diallyl disulfide (DADS), an organic component of allicin abstracted from garlic, possesses multi-target antitumor activity. DJ-1 performs a vital function in promoting AKT aberrant activation via down-regulating phosphatase and tensin homologue (PTEN) in tumors. It is unknown the involvement of DJ-1 in epithelial-mesenchymal transition (EMT) of gastric cancer (GC) cells. The purpose of this study is to investigate whether diallyl disulfide (DADS) intervenes in the role of DJ-1 in GC. Based on the identification that the correlation between high DJ-1 and low PTEN expression in GC was implicated in clinical progression, we illuminated that down-regulation of DJ-1 by DADS aided in an increase in PTEN expression and a decrease in phosphorylated AKT levels, which was in line with the results manifested in the DJ-1 knockdown and overexpressed cells, concurrently inhibiting proliferation, EMT, migration, and invasion. Furthermore, the antagonistic effects of DADS on DJ-1 were observed in in vivo experiments. Additionally, DADS mitigated the DJ-1-associated drug resistance. The current study revealed that DJ-1 is one of potential targets for DADS, which hopefully provides a promising strategy for prevention and adjuvant chemotherapy of GC.

miR-199a/b-3p inhibits HCC cell proliferation and invasion through a novel compensatory signaling pathway DJ-1\Ras\PI3K/AKT

Several studies have reported the effects of DJ-1 gene and miR-199a/b-3p on HCC development. However, whether miR-199a/b-3p regulates HCC progression through a novel compensatory signaling pathway involving DJ-1, Ras, and PI3K/AKT remains unknown. We used (TCGA, HPA, miRWalk and Target scan) databases, cancer and para-tissue HCC patients, dual-luciferase reporter gene analysis, proteomic imprinting, qPCR, cell proliferation, scratch, transport, and flow cytometry to detect the molecular mechanism of DJ-1 and miR-199a/b-3p co-expression in HCC cell lines. Bioinformatics analysis showed that DJ-1 was highly expressed in HCC ((P < 0.001) were closely associated with tumor stage (T), portal vein vascular invasion, OS, DSS, and PFI (P < 0.05); miR-199a/b-3p was lowly expressed in HCC (P < 0.001), which was the upstream regulator of DJ-1. Spearman coefficient r = -0.113, P = 0.031; Dual luciferase gene report verified the negative targeting relationship between them P< 0.001; Western blotting demonstrated that miR-199a/b-3p could inhibit the protein expression of DJ-1, Ras and AKT(P < 0.05); The results of CCK8, cell scratch, Transwell migration and flow cytometry showed that OE + DJ-1 increased the proliferation, migration and invasion ability of HepG2 cells, and decreased the apoptosis process, and the differences were statistically significant (P < 0.05), while miR-199a/b-3p had the opposite effect (P < 0.05).

Effects of DJ‑1 on apoptosis and mitophagy of glomerular podocytes

By studying the effects of DJ-1 overexpression and silencing on the morphological structure and mitophagy of glomerular podocytes, the present study aimed to identify the effects of DJ-1 on glomerular podocyte apoptosis and mitophagy. MPC5 mouse glomerular podocytes were cultured in vitro and divided into four groups: Control, DJ-1 overexpression, empty vector and DJ-1 silencing. DJ-1 gene overexpression and silencing models were prepared, the morphological structures of podocytes and mitochondria in each group were observed, and podocyte apoptosis and DJ-1/PTEN expression were subsequently detected in each group. The experimental results showed reduced volume, retracted foot processes, loosened intercellular connections, presence of dead cells, increased apoptotic rate, increased expression of PTEN, and swollen mitochondria due to the number of vacuoles and autophagosomes in podocytes in the DJ-1 silencing group. The surface areas of podocytes in the DJ-1 overexpression group were greater than those in the control group. Moreover, the structure of the foot processes was more obvious, the number of cells was greater, the intercellular connections were closer, the apoptotic rate was reduced, the expression of PTEN was decreased, the mitochondrial structure was more obvious and the mitochondrial cristae were more whole. Notably, there were no differences between the empty vector and control groups. In conclusion, these results indicated that DJ-1 may regulate podocyte apoptosis and mitophagy through the DJ-1/PTEN pathway, and could maintain the stability of the normal morphology, structure and function of glomerular podocytes.

Importance of DJ-1 in autophagy regulation and disease

Autophagy is a highly conserved biological process that has evolved across evolution. It can be activated by various external stimuli including oxidative stress, amino acid starvation, infection, and hypoxia. Autophagy is the primary mechanism for preserving cellular homeostasis and is implicated in the regulation of metabolism, cell differentiation, tolerance to starvation conditions, and resistance to aging. As a multifunctional protein, DJ-1 is commonly expressed in vivo and is associated with a variety of biological processes. Its most widely studied role is its function as an oxidative stress sensor that inhibits the production of excessive reactive oxygen species (ROS) in the mitochondria and subsequently the cellular damage caused by oxidative stress. In recent years, many studies have identified DJ-1 as another important factor regulating autophagy; it regulates autophagy in various ways, most commonly by regulating the oxidative stress response. In particular, DJ-1-regulated autophagy is involved in cancer progression and plays a key role in alleviating neurodegenerative diseases(NDS) and defective reperfusion diseases. It could serve as a potential target for the regulation of autophagy and participate in disease treatment as a meaningful modality. Therefore, exploring DJ-1-regulated autophagy could provide new avenues for future disease treatment.

Resveratrol inhibits autophagy against myocardial ischemia-reperfusion injury through the DJ-1/MEKK1/JNK pathway

Resveratrol (RES), a natural polyphenolic compound found in red wine and grape skins, has attracted significant attention due to its cardioprotective properties. DJ-1, a multifunctional protein that participated in transcription regulation and antioxidant defense, was shown to provide a significant protective impact in cardiac cells treated with ischemia-reperfusion. We created a myocardial ischemia-reperfusion (I/R) model in vivo and in vitro by ligating the left anterior descending branch of rats and subjecting H9c2 cells to anoxia/reoxygenation (A/R) to investigate whether RES reduces myocardial ischemia-reperfusion injury by upregulating DJ-1. We discovered that RES dramatically enhanced cardiac function in rats with I/R. Subsequently, we found that RES prevented the rise in autophagy (P62 degradation and LC3-II/LC3-I increase) induced by cardiac ischemia-reperfusion in vitro and in vivo. Notably, the autophagic agonist rapamycin (RAPA) eliminated RES-induced cardioprotective effects. In addition, Further data showed that RES significantly increased the expression of DJ-1 in the myocardium with the treatment of I/R. At the same time, pretreatment with RES reduced phosphorylation of MAPK/ERK kinase kinase 1 (MEKK1) and Jun N-terminal Kinase (JNK) stimulated by cardiac ischemia-reperfusion, and Beclin-1 mRNA and protein levels while decreasing lactate dehydrogenase (LDH) and improving cell viability. However, the lentiviral shDJ-1 and JNK agonist anisomycin disrupted the effects of RES. In summary, RES could inhibit autophagy against myocardial ischemia-reperfusion injury through DJ-1 modulation of the MEKK1/JNK pathway, providing a novel therapeutic strategy for cardiac homeostasis.

The inhibitory effect and mechanism of Yi-qi-hua-yu-jie-du decoction on the drug resistance of gastric cancer stem cells based on ABC transporters

Background

The drug resistance of tumor stem cells is an obstacle in gastric cancer (GC) treatment and the high expression of ABC transporters is a classic reason for drug resistance. This study aimed to construct a reliable GC drug-resistant stem cell model and explore the inhibitory effect and mechanism of Yi-qi-hua-yu-jie-du medicated serum (YQHY) on the drug resistance of GC stem cells based on ABC transporters.

Methods

The tumor stemness biomarker CD44 was primary identification from WGCNA. The magnetic-activated cell sorting (MACS) method was used to separate CD44( +)BGC823/5-Fu (BGC823/5–Fu-CSCs) cells and the stemness characteristics were verified from multiple dimensions. Then, the drug resistance index and expression of ABC transporter genes MDR1 and MRP1 were detected in CD44(−)/CD44(+) cells. The inhibition and apoptosis rates of the cells administrated with YQHY or/and 5-Fu were calculated to confirm that YQHY can suppress the drug resistance of BGC823/5-Fu-CSCs. Afterwards, the effects of YQHY on the expression of MDR1 and MRP1 and the activation of the PI3K/Akt/Nrf2 pathway were observed. Finally, under the administration of IGF-1 (the activator of PI3K/Akt pathway) and Nrf2 siRNA, the mechanism of YQHY on reversing the drug resistance of BGC823/5–Fu-CSCs through inhibiting the expression of MDR1 and MRP1 via PI3K/Akt/Nrf2 was verified.

Results

CD44 was a reliable GC stemness biomarker and can be applied to construct the drug-resistant GC stem cell model CD44(+)BGC823/5-Fu. The growth rate, cell proliferation index, soft agar colony formation, expression of stemness specific genes and tumorigenesis ability of CD44(+)BGC823/5-Fu cells were significantly higher than those of CD44(−)BGC823/5-Fu cells. BGC823/5–Fu-CSCs exhibited strong drug resistance to 5-Fu and high expression of ABC transporter genes MDR1 and MRP1 compared to CD44(-) cells. YQHY increased the inhibition and apoptosis rates to efficiently inhibit the drug resistance of BGC823/5–Fu-CSCs. Meanwhile, it suppressed the expression of MDR1 and MRP1 and restrained the activation of PI3K/Akt/Nrf2 signaling pathway. Finally, it was found that IGF-1 partially restored the activation of PI3K/Akt/Nrf2 pathway, alleviated the inhibition of MDR1 and MRP1, blocked the proliferation-inhibitory and apoptosis-promotion effects. YQHY and si-Nrf2 synergistically suppressed the MDR1/MRP1 expression and the drug resistance of BGC823/5–Fu-CSCs.

Conclusions

CD44 was a reliable GC stemness biomarker, and the high expression of ABC transporter genes MDR1 and MRP1 was an important feature of drug-resistant stem cells. YQHY inhibited the MDR1 and MRP1 expression via PI3K/Akt/Nrf2 pathway, thus reversing the drug resistance of BGC823/5–Fu-CSCs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13020-022-00647-y.

ROS-Induced DCTPP1 Upregulation Contributes to Cisplatin Resistance in Ovarian Cancer

Cisplatin resistance hinders the improvement of the prognosis of patients with ovarian cancer. Cisplatin induces cancer cell apoptosis by inducing reactive oxygen species (ROS). dCTP pyrophosphatase 1 (DCTPP1) is a newly discovered dNTP pyrophosphatase. This study aimed to identify the role of DCTPP1 in oxidative stress and cisplatin response of ovarian cancer. Our results indicates cisplatin-induced ROS generation was responsible for the upregulation of DCTPP1 in ovarian cancer cells, whereas DCTPP1 knockdown significantly enhanced the sensitivity of ovarian cancer cells to cisplatin, reflect in reactive oxygen species (ROS) generation, double-strand DNA breaks, and cell apoptosis. The expression of redox-related genes and the activation of the PI3/Akt signaling pathway were also inhibited by DCTPP1 knockdown. Our data proposes that the development of therapeutic approaches targeting DCTPP1 may be useful in the treatment of ovarian cancer.

DJ-1 activates the noncanonical NF-κB pathway via interaction with Cezanne to inhibit the apoptosis and promote the proliferation of Ishikawa cells

BACKGROUND

Endometrial cancer is generally one of the most evident malignant tumours of the female reproductive system, and the mechanisms underlying its cell proliferation and apoptosis are key to research in gynaecological oncology. In the paper, the in-depth molecular mechanism by which DJ-1 protein regulates the proliferation and apoptosis of Ishikawa cells was investigated.

METHODS AND RESULTS

DJ-1 knockdown and overexpressing Ishikawa stable cell lines were established by lentiviral transduction. The levels of DJ-1 and noncanonical NF-κB signaling key proteins were evaluated by Western blotting. Cell counting kit-8 (CCK-8) and flow cytometry were applied to analyze the cell viability and apoptosis. Co-immunoprecipitation experiment was utilized to assess the DJ-1-Cezanne interaction. The results showed that DJ-1 overexpression conferred apoptosis resistance and high proliferation on Ishikawa cells, while DJ-1 knockdown in Ishikawa cells produced the opposite results. These findings again suggested that DJ-1 inhibits the apoptosis and promotes the proliferation of Ishikawa cells. More crucially, further data showed that the noncanonical NF-κB activation was required for the regulation of Ishikawa cell proliferation and apoptosis by DJ-1. Meanwhile, it was found that noncanonical NF-κB pathway may be activated by DJ-1 interacting with and negatively regulating Cezanne in Ishikawa cells.

CONCLUSIONS

Overall, this work revealed that DJ-1 associates with and negatively regulates Cezanne and consequently triggers the noncanonical NF-κB activation, thereby regulating Ishikawa cell proliferation and apoptosis.

Targeting IFN-γ-inducible lysosomal thiol reductase overcomes chemoresistance in AML through regulating the ROS-mediated mitochondrial damage

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GILT is upregulated in chemoresistant LSC-enriched CD34+ progenitor cells.

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Inhibition of GILT in AML cells sensitized them to Ara-C treatment through ROS-mediated mitochondrial damage and apoptosis.

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PI3K/Akt/NRF2 pathway inhibition is critical for the intracellular oxidative state in GILT-suppression AML cells after Ara-C treatment.

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GILT expression is related to a poor prognosis in AML patients.

The persistence of leukemia stem cells (LSCs) is one of the leading causes of chemoresistance in acute myeloid leukemia (AML). To explore the factors important in LSC-mediated resistance, we use mass spectrometry to screen the factors related to LSC chemoresistance and defined IFN-γ-inducible lysosomal thiol reductase (GILT) as a candidate. We found that the GILT expression was upregulated in chemoresistant CD34+ AML cells. Loss of function studies demonstrated that silencing of GILT in AML cells sensitized them to Ara-C treatment both in vitro and in vivo. Further mechanistic findings revealed that the ROS-mediated mitochondrial damage plays a pivotal role in inducing apoptosis of GILT-inhibited AML cells after Ara-C treatment. The inactivation of PI3K/Akt/ nuclear factor erythroid 2-related factor 2 (NRF2) pathway, causing reduced generation of antioxidants such as SOD2 and leading to a shifted ratio of GSH/GSSG to the oxidized form, contributed to the over-physiological oxidative status in the absence of GILT. The prognostic value of GILT was also validated in AML patients. Taken together, our work demonstrated that the inhibition of GILT increases AML chemo-sensitivity through elevating ROS level and induce oxidative mitochondrial damage-mediated apoptosis, and inhibition of the PI3K/Akt/NRF2 pathway enhances the intracellular oxidative state by disrupting redox homeostasis, providing a potentially effective way to overcome chemoresistance of AML.

Cytoprotective Mechanisms of DJ-1: Implications in Cardiac Pathophysiology

DJ-1 was originally identified as an oncogene product while mutations of the gene encoding DJ-1/PARK7 were later associated with a recessive form of Parkinson's disease. Its ubiquitous expression and diversity of function suggest that DJ-1 is also involved in mechanisms outside the central nervous system. In the last decade, the contribution of DJ-1 to the protection from ischemia-reperfusion injury has been recognized and its involvement in the pathophysiology of cardiovascular disease is attracting increasing attention. This review describes the current and gaps in our knowledge of DJ-1, focusing on its role in regulating cardiovascular function. In parallel, we present original data showing an association between increased DJ-1 expression and antiapoptotic and anti-inflammatory markers following cardiac and vascular surgical procedures. Future studies should address DJ-1's role as a plausible novel therapeutic target for cardiovascular disease.

Roles of Nrf2 in Gastric Cancer: Targeting for Therapeutic Strategies

Nuclear Factor Erythroid 2-Related Factor 2 (Nrf2) is a specific transcription factor with potent effects on the regulation of antioxidant gene expression that modulates cell hemostasis under various conditions in tissues. However, the effects of Nrf2 on gastric cancer (GC) are not fully elucidated and understood. Evidence suggests that uncontrolled Nrf2 expression and activation has been observed more frequently in malignant tumors, including GC cells, which is then associated with increased antioxidant capacity, chemoresistance, and poor clinical prognosis. Moreover, Nrf2 inhibitors and the associated modulation of tumor cell redox balance have shown that Nrf2 also has beneficial effects on the therapy of various cancers, including GC. Based on previous findings on the important role of Nrf2 in GC therapy, it is of great interest to scientists in basic and clinical tumor research that Nrf2 can be active as both an oncogene and a tumor suppressor depending on different background situations.