Chuanwu Cao

Long noncoding RNA MALAT1 regulates renal tubular epithelial pyroptosis by modulated miR-23c targeting of ELAVL1 in diabetic nephropathy

ABSTRACT Diabetic nephropathy is a common kidney condition in patients with diabetes mellitus, which can result in renal failure. Pyroptosis, the process of pro‐inflammatory programmed cell death, plays an important role in the pathogenesis of this disease. Long non‐coding RNA MALAT1 has also been shown to be involved in diabetic nephropathy. Here, we investigated the role of MALAT1 and the microRNA miR‐23c and its target gene ELAVL1 in renal tubular epithelial cells. Our data demonstrated that MALAT1 expression was substantially increased but miR‐23c was decreased in streptozotocin‐induced diabetic rats and in high‐glucose‐treated HK‐2 cells. Downregulation of MALAT1 or upregulation the expression of miR‐23c inhibited pyroptosis in HK‐2 cells. In an effort to understand the signaling mechanisms underlying the pro‐pyroptotic properties of MALAT1 and the anti‐pyroptotic properties of miR‐23c, we found that inhibiting the expression of MALAT1 downregulated the expression of ELAVL1, NLRP3, Caspase‐1 and the pro‐inflammatory cytokine IL‐1&bgr;. These findings were replicated by upregulation of miR‐23c. Moreover, luciferase assays showed that miR‐23c, as a target of MALAT1, directly repressed ELAVL1 expression and then decreased the expression of its downstream protein NLRP3. The expression of MALAT1 antagonized the effect of miR‐23c on the downregulation of its target ELAVL1 and inhibited hyperglycemia‐induced cell pyroptosis. This mechanism may contribute to a better understanding of diabetic nephropathy pathogenesis and facilitate the development of new therapeutic strategies for the treatment of this disease.

Combination therapy with transarterial chemoembolization and interferon-α compared with transarterial chemoembolization alone for hepatitis B virus related unresectable hepatocellular carcinoma.

Background and Aims:  The present study was carried out to test the hypothesis that interferon‐α (IFN‐α) treatment would reduce or postpone the recurrence rate and improve the overall survival rate in patients after transarterial chemoembolization (TACE) treatment of hepatitis B virus (HBV) related unresectable hepatocellular carcinoma (HCC).

ROBO3 promotes growth and metastasis of pancreatic carcinoma

Pancreatic carcinoma is a highly lethal malignancy with an extremely poor prognosis. Recent genome-wide studies have implicated axon guidance pathways, including the SLIT/ROBO pathway, in pancreatic tumor development and progression. Here we showed that ROBO3 expression is up-regulated in pancreatic cancer tissue samples and cell lines. Over-expression of ROBO3 promotes pancreatic cancer cell growth, invasion and metastasis in vitro and in mouse xenograft tumor models. We identified miR-383 as a suppressor of ROBO3, and revealed its expression to be inversely correlated with ROBO3. Over-expression of ROBO3 activates Wnt pathway components, β-catenin and GSK-3, and the expression of markers indicating an EMT. By means of immunoprecipitation, we revealed an interaction between Wnt inhibitor SFRP and ROBO3 in pancreatic cancer cell lines. Our work suggests that ROBO3 may contribute to the progression of pancreatic cancer by sequestering Wnt inhibitor SFRP, which in turn leads to increased Wnt/β-catenin pathway activity. We also confirmed that ROBO3 increases with clinical grade and miR-383 expression is inversely correlated to that of ROBO3.

Tripterine treatment improves endothelial progenitor cell function via integrin-linked kinase.

Background/Aims: Atherosclerosis is associated with dysfunction of endothelial progenitor cells (EPCs). Tripterine, a chemical compound derived from the Chinese medicinal plant Tripterygium wilfordii Hook, displays anti-inflammatory properties in several animal models. We hypothesized that tripterine can improve EPC function and thus the efficiency of EPC transplantation. Methods and Results: Tripterine preconditioning (2.5 μM, 4 h) improved EPC proliferation, tube formation, migration, and adhesion, and reduced apoptosis in cells cultured in ox-LDL (200 µg/ml). Tripterine restored integrin-linked kinase (ILK) levels downregulated by ox-LDL in EPCs, suggesting the involvement of the ILK/Akt pathway. Small interfering RNA-mediated depletion of ILK and dominant-negative ILK transduction inhibited the phosphorylation of the ILK downstream signaling targets protein kinase B/Akt and glycogen synthase kinase 3-beta (GSK-3β), and reduced β-catenin and cyclin D1 expression. In atherosclerotic mice injected with green fluorescent protein-labeled EPCs to evaluate EPC function, tripterine decreased aortic lesions and plaque deposition, and injection of tripterine-treated EPCs restored ILK levels. Conclusion: The present results suggest that tripterine improves vascular function in atherosclerosis by enhancing EPC function through a mechanism involving the ILK signaling pathway.

Expression of Rab25 correlates with the invasion and metastasis of gastric cancer

The objective of this study was to determine the expression of the important vesicle trafficking-regulating factor Rab25 in human gastric cancer tissues, to analyze the correlation between Rab25 protein expression with gastric cancer occurrence and development, and to discuss the correlation of Rab25 protein expression with gastric cancer cell metastasis. The overall aim was to provide experimental evidence that can be used to design future biological treatments of human gastric cancer. Human gastric cancer tissue and the adjacent normal gastric tissue were surgically removed, and immunohistochemistry and Western blotting were used to detect Rab25 protein expression. The correlation between Rab25 protein expression with the development and pathological characteristics of gastric cancer was analyzed. Using RNAi, Rab25 expression was reduced in the gastric cancer cell line MGC80-3, and the changes in MGC80-3 cell invasiveness were then monitored. Immunohistochemistry showed that the Rab25 protein expression rates were 78.21% and 23.08% in gastric carcinoma and the adjacent normal gastric tissue, respectively. Immunohistochemistry and Western blot results showed that Rab25 protein expression in gastric cancer was significantly higher than in adjacent normal gastric tissues (P<0.01). Less differentiated gastric cancer cells had higher expression of Rab25 protein (P<0.01). Gastric carcinomas from patients with a late pathological stage (III-IV) had significantly higher Rab25 protein expression than early stage (I-II) patients (P<0.01). Gastric carcinomas from patients with lymph node metastasis had significantly higher Rab25 protein expression than lymph node metastasis-free patients (P<0.01). Gastric carcinomas from patients with distant metastases had significantly higher Rab25 protein expression than the distant metastasis-negative patients (P<0.01). Rab25 protein expression in gastric cancer was not affected by the patients(,) sex, age, or tumor size (P>0.05). MGC80-3 cells transfected with Rab25 siRNA had significantly lower Rab25 protein expression (P<0.01) and a significantly lower number of cells that passed through a Transwell chamber compared with non-transfected controls and the transfected control group (P<0.01). Rab25 protein expression is associated with the development of gastric cancer. siRNA knockdown of Rab25 protein expression in MGC80-3 gastric cancer cells reduced MGC80-3 cell invasiveness and provided experimental evidence for potential future biological treatment strategies of human gastric cancer.

Liver abscess following transarterial chemoembolization for the treatment of hepatocellular carcinoma: A retrospective analysis of 23 cases

Objective: To investigate the incidence, management, and outcome of a liver abscess after transarterial embolization/chemoembolization (TAE/TACE) therapy for hepatocellular carcinoma (HCC). Materials and Methods: From May 2007 to May 2014, all patients complicated with liver abscess following TAE/TACE for HCC were identified and analyzed at four medical centers. Results: During the study period, a total of 6984 TAE/TACE procedures were performed among 3129 patients, and a total of 23 patients developed liver abscess with the incidence of 0.33% (23/6984) per procedure. There were 21 males and 2 females, and mean age of 52.1 ± 12.1 years. The mean interval from last TAE/TACE procedure to the diagnosis of liver abscess was 12.9 ± 6.6 days. All the patients received intravenous antibiotics, with ten patients had a percutaneous drain, one each for percutaneous aspiration and surgery. Complications related to the liver abscess were hepatorrhexis and pleural effusion (n = 1), pleural effusion (n = 1), and obstructive jaundice (n = 1), all of which were resolved after conservative treatments. The serum alpha-fetoprotein (AFP) levels were significantly reduced at 6 months after treatment (P < 0.01) in 15 patients whose AFP > 400 ng/mL preprocedure. Complete or partial tumor response at 6 months after TAE/TACE was achieved in three and twenty patients, respectively; and 6 months survival was 100%. Conclusions: The incidence of a liver abscess after TAE/TACE is low; antibiotics therapy along was successful in about half patients, and percutaneous abscess aspiration/drainage were necessary in large size abscess and severely symptomatic patients; the outcomes are benign without worsening of the progression of underlying HCC.

A phase II study of intra-arterial chemotherapy of 5-fluorouracil, cisplatin, and mitomycin C for advanced nonresectable gastric cancer

The best choice of chemotherapy regimen for patients with advanced gastric cancer (AGC) is still a matter of controversy and requires further investigation. This study was performed to evaluate the efficacy and safety of intra-arterial infusion chemotherapy of 5-fluorouracil 1000 mg/m2, cisplatin 50 mg/m2, and mitomycin C 10 mg/m2 (FCM) repeated every 6 weeks, as first-line treatment for AGC. Forty-seven (95.9%) of the 49 patients were assessable for response. Four cases of complete response and 28 cases of partial response were confirmed, giving an overall response rate of 65.3% [95% confidence interval (CI): 52.0–78.6%]. The median time to progression and overall survival for all patients was 8.3 months (95% CI: 6.8–9.8 months) and 14.5 months (95% CI: 12.0–17.0 months). The estimate of overall survival at 12 and 24 months was 55.1% (95% CI: 41.2–69.0%) and 18.4% (95% CI: 7.5–29.2%), respectively. Most patients experienced neutropenia during their course of therapy with 21.3% of patients (n = 10) for grade 3/4 neutropenia. Grade 3 stomatitis, lethargy, and palmar-plantar erythema were observed in two (4.3%), eight (17.0%), and one (2.1%) patients, respectively. Yet, no grade 4 nonhematological toxicity was observed. Intra-arterial infusion chemotherapy of 5-fluorouracil 1000 mg/m2, cisplatin 50 mg/m2, and mitomycin C 10 mg/m2 is a tolerated treatment modality with promising activity in patients with previously untreated AGC.

Nanosphere-mediated co-delivery of VEGF-A and PDGF-B genes for accelerating diabetic foot ulcers healing in rats

Diabetic ischemic ulcer is an intractable diabetic complication. Angiogenesis is a critical factor for wound healing in patients with diabetic foot wounds. Sustained gene delivery could be notably necessary in modulating gene expression in chronic ulcer healing and might be a promising approach for diabetic foot ulcers. In the present study, Sprague–Dawley rats were used to establish diabetic foot ulcer models by streptozotocin and skin biopsy punch. The plasmids expressing VEGF-A and PDGF-B were prepared and then incorporated with polylactic-co-glycolic acid (PLGA) nanospheres to upregulate genes expression. The aim of this study was to explore whether the engineered VEGF-A and PDGF-B based plasmid-loaded nanospheres could be upregulated in streptozotocin-induced diabetic rats and improve the wound healing. The cultured fibroblasts could be effectively transfected by means of nanosphere/plasmid in vitro. In vivo, the expression of VEGF-A and PDGF-B was significantly upregulated at full-thickness foot dorsal skin wounds and the area of ulceration was progressively and significantly reduced following treatment with nanosphere/plasmid. These results indicated that combined gene transfer of VEGF-A and PDGF-B could improve reparative processes in the wounded skin of diabetic rats and nanosphere may be a potential non-viral vector for gene therapy of the diabetic foot ulcer.

The NFκΒ signaling pathway serves an important regulatory role in Klebsiella pneumoniae liver abscesses

The incidence of Klebsiella pneumoniae liver abscess (KPLA) has increased in a number of Asian countries over the past 30 years. Diabetes mellitus (DM) is a risk factor for KPLA. The prevalence and clinical features of KPLA in patients with and without DM have been well described; however, the underlying molecular mechanism responsible for the increased incidence of KPLA in patients with DM remains unclear. In the present study, a mouse model of DM was constructed and mice were infected with K. pneumoniae. Tissues were harvested for immunohistochemical and inflammatory factor expression analyses. The results revealed that the number of liver abscesses in mice with DM was greater than that observed in normal mice. The expression of interleukin (IL)-1β, IL-2, IL-6, macrophage inflammatory protein-1α and tumor necrosis factor-α in the liver tissues of mice with DM was significantly higher compared with normal mice. Western blotting results revealed that the expression of phosphorylated (p)-inhibitor of nuclear factor κB (NFκB) kinase subunit β, p-NFκB and p-inhibitor of NFκB was significantly increased in the liver tissue of mice with DM compared with that of normal mice. These results suggest that activation of the NFκB signaling pathways has a regulatory effect on the pathogenesis of K. pneumoniae bacteria liver abscesses and that high glucose conditions may promote the activation of NFκB signaling.

MiR-31 regulates the function of diabetic endothelial progenitor cells by targeting Satb2

Endothelial malfunctions in patients with diabetes are known to result in vascular diseases, and endothelial progenitor cells (EPCs) are indispensable for the functional preservation of the vascular endothelium. MicroRNA-31 (miR-31) has been found to be able to modulate the differentiation of stem cells. However, it is still unclear how miR-31 functions in diabetic EPCs. The aim of this study was to investigate how miR-31 regulates diabetic EPC function. In the current study, miR-31 expression was compared between normal and diabetic EPCs. Satb2 was recognized as a functionally related target of miR-31 in EPCs according to computational prediction. We also explored the role of miR-31 in terms of its anti-apoptotic effects. A remarkable elevation in miR-31 expression was found in diabetic EPCs, and this elevated expression resulted in suppressed cell proliferation under high glucose. It was also found that miR-31 targets Satb2, leading to the anti-apoptotic effect and maintenance of the functions of EPCs. Furthermore, knockdown of Satb2 exhibited an inhibitory effect on proliferation and migration of EPCs in both healthy and diabetic subjects, which showed the same trend as miR-31 overexpression. Conversely, overexpression of Satb2 showed the opposite effect. Moreover, overexpression of Satb2 attenuated the miR-31-induced migration and colony-forming ability reduction and apoptosis induction of EPCs in both healthy and diabetic subjects. In diabetic EPCs, elevated glucose level was found to up-regulate miR-31 expression, which in turn enhanced the malfunction and death of EPCs. In conclusion, our results indicate that up-regulation of miR-31 may underlie endothelial dysfunction in diabetes by targeting Satb2.