Role of oxysterol-binding protein-related proteins in malignant human tumours

The oxysterol-binding protein-related protein(ORP)family is a group of proteins that mediate oxysterol metabolism and bioactivity in cells.ORPs constitute a large family of lipid transfer proteins.Much of the current evidence indicates that certain members of the family of oxysterol-binding proteins(OSBPs)can lead to cancer.Many studies have revealed the putative roles of OSBPs in various cancer types.However,the exact effects and mechanisms of action of members of the OSBP/ORP family in cancer initiation and progression are currently unclear.This review focuses on ORP family members that can accelerate human tumour cell proliferation,migration,and invasion.The mechanisms and functions of various ORPs are introduced in detail.We also attempt to identify the roles of these proteins in malignant tumours with the ultimate aim of determining the exact role of the OSBP/ORP family in human tumour cells.

Megestrol acetate plus metformin for fertility-sparing treatment of atypical endometrial hyperplasia and early-stage endometrial adenocarcinoma: a prospective study

Objective To evaluate the efficacy of medroxyprogesterone acetate(MA)plus metformin as the primary fertility-sparing treatment for atypical endometrial hyperplasia(AEH)and early-stage grade 1 endometrial adenocarcinoma(G1 EAC)and the recurrence rate after treatment.Methods Sixty patients(aged 20-42 years)with AEH and/or grade 1 EAC limited to the endometrium were enrolled prospectively and randomized into two groups(n=30)to receive oral MA treatment at the daily dose of 160 mg(control)or MA plus oral metformin(850 mg,twice a day)for at least 6 months.The treatment could extend to 12 months until a complete response(CR)was achieved,and follow-up hysteroscopy and curettage were performed every 3 months.For all the patients who achieved CR,endometrial expressions of IGFBP-rP1,p-Akt and p-AMPK were detected immunohistochemically.Results A total of 58 patients completed the treatment.After 9 months of treatment,23(76.7%)patients in the combined treatment group and 20(71.4%)in the control group achieved CR;two patients in the control group achieved CR after converting to the combined treatment.The recurrence rate did not differ significantly between the control group and combined treatment group(30.0%vs 22.7%,P>0.05).Ten(35.7%)patients in the control group experienced significant weight gain of 5.7±6.1 kg,while none of the patients receiving the combined treatment exhibited significant body weight changes.Compared with the control group,the patients receiving the combined treatment showed enhanced endometrial expressions of IGFBP-rP1 and p-AMPK with lowered p-Akt expression.Conclusion Metformin combined with MA may provide an effective option for fertility-sparing treatment of AEH and grade 1 stage IA EAC,and the clinical benefits of metformin for controlling MA-induced weight gain and promoting endometrial expressions of IGFBP-rP1 and p-AMPK while inhibiting p-Akt expression warrants further study.

IGFBPrP1 induces liver fibrosis by inducing hepatic stellate cell activation and hepatocyte apoptosis via Smad2/3 signaling

AIM: To investigate the role and mechanism of insulin-like growth factor binding protein-related protein 1 (IGFBPrP1) in the development of liver fibrosis.

Effects of insulin-like growth factor binding protein-related protein 1 in mice with hepatic fibrosis induced by thioacetamide

Background Insulin-like growth factor binding protein-related protein 1 （IGFBPrP1） can activate hepatic stellate cells and increase extracellular matrix （ECM） in vitro. However, the effects of IGFBPrP1 in mice with hepatic fibrosis, and the mechanisms of these effects, are currently unknown. We aim to address these issues in this study. Methods Intraperitoneal injection of thioacetamide （TAA） is a classic method for establishing a mouse model of hepatic fibrosis. Using this model, we administered anti-IGFBPrP1 antibody, again via intraperitoneal injection. The morphological changes of liver fibrosis were observed with both HE and Masson stainning. The immunohistochemical assays and Western blotting were used to measure changes in IGFBPrP1, a-smooth muscle actin （a-SMA） and ECM in liver tissues, and the expression of transforming growth factor-β1 （TGF-β1） and Smad3. Data were statistically analyzed using one-way analysis of variance （ANOVA）, the SNK-q test for inter-group differences. Results The Masson staining analysis showed that compared with normal control group, content of collagen fiber in TAA5w group was significantly increased （P 〈0.01）, and it was significantly decreased in TAA5w/alGFBPrP1 group compared with in TAA5w group （P 〈0.01）. The expression of hepatic IGFBPrP1, a-SMA, TGF-β1, Smad3, collagen 1 and fibronectin （FN） was significantly up-regulated in the TAA5w group （P 〈0.01）. Anti-IGFBPrP1 treatment reversed these changes （P 〈0.01）. Conclusions IGFBPrP1 plays an important role in the development of hepatic fibrosis. Anti-IGFBPrP1 prevents fibrosis in mice by suppressing the activation of hepatic stellate cells, inhibiting the synthesis of major components of the ECM （namely, collagen I and FN）. The mechanism for this suppression of fibrosis is associated with the TGF-β1/Smad3 signaling pathways.

Differential expression of glial cell line-derived neurotrophic factor splice variants in the mouse brain

Glial cell line-derived neurotrophic factor(GDNF) plays a critical role in neuronal survival and function. GDNF has two major splice variants in the brain,α-pro-GDNF and β-pro-GDNF, and both isoforms have strong neuroprotective effects on dopamine neurons. However, the expression of the GDNF splice variants in dopaminergic neurons in the brain remains unclear. Therefore, in this study, we investigated the mRNA and protein expression of α-and β-pro-GDNF in the mouse brain by real-time quantitative polymerase chain reaction, using splice variant-specific primers, and western blot analysis. At the mRNA level,β-pro-GDNF expression was significantly greater than that of α-pro-GDNF in the mouse brain. In contrast, at the protein level,α-pro-GDNF expression was markedly greater than that of β-pro-GDNF. To clarify the mechanism underlying this inverse relationship in mRNA and protein expression levels of the GDNF splice variants, we analyzed the expression of sorting protein-related receptor with A-type repeats(SorLA) by real-time quantitative polymerase chain reaction. At the mRNA level, SorLA was positively associated with β-pro-GDNF expression, but not with α-pro-GDNF expression. This suggests that the differential expression of α-and β-pro-GDNF in the mouse brain is related to SorLA expression. As a sorting protein, SorLA could contribute to the inverse relationship among the mRNA and protein levels of the GDNF isoforms. This study was approved by the Animal Ethics Committee of Xuzhou Medical University, China on July 14, 2016.