[Gene transfer of von Hippel-Lindau inhibits the growth of transplanted solid tumors]

OBJECTIVE

To explore the effect of von Hippel-Lindau(VHL) gene on growth of EL-4 solid tumors in vivo.

METHODS

C57BL/6 mice model of solid tumors was established by subcutaneous injection of EL-4 lymphoma cells. Mice were randomly divided into two groups as treatment group (n=6) and control group (n=6) when tumor diameter increased to 0.1 cm and 0.4 cm respectively. Plasmid pcDNA3-VHL was injected into solid tumor in treatment group, empty pcDNA3 vector in control group. The growth of tumor was observed. Immunohistochemistry and Western blot analysis were used to examine the transgenic expression of VHL, hypoxia inducible factor-1alpha (HIF)-1alpha, bcl-2 and VEGF. Microvessel density (MVD) and apoptosis index (AI) of tumors were also detected.

RESULTS

VHL gene transfer eradicated tumors with small size (0.1 cm diameter), but it only retarded the growth of large tumors (0.4 cm diameter). VHL was overexpressed, the expression levels of VEGF, HIF-1alpha and bcl-2 were reduced in treatment group compared with those in the control group. The level of MVD was significantly lower in treatment group (P< 0.05), but AI was higher in treatment group compared with those in the control group (P< 0.01).

CONCLUSION

VHL gene therapy can inhibit the growth of EL-4 solid tumor in vivo.

[Antisense hypoxia inducible factor-1alpha and B7-1 combination gene therapy for mouse lymphoma]

OBJECTIVE

To investigate the synergistic effects of antisense HIF-1alpha gene therapy combined with B7-1-mediated immunotherapy on cancer treatment.

METHODS

Antisense HIF-1alpha and B7-1 expression vector were constructed. Lymphoma cells EL-4 were injected subcutaneously into C57BL/6 mice and transplanted lymphomas were established. The mice received either antisense HIF-1alpha, B7-1, or a combinational agent, complexed with DOTAP cationic liposomes. The tumor growth in the mice was monitored. Expression of HIF-1alpha, B7-1 and VEGF were detected by immunohistochemistry and Western blotting. The tumor blood vessels were immunostained with CD31- antibodies and the tumor vascular density was assessed by light microscopy.

RESULTS

Gene transfer of plasmid expressing the encoded antisense HIF-1alpha inhibited VEGF expression and reduced vascular density in the tumors, eradicated tumors in diameter smaller than 0.1 cm and only retarded the growth of larger tumors. Whereas combination of antisense HIF-1alpha gene therapy and B7-1 immunotherapy eradicated all tumors in diameter of 0.4 cm.

CONCLUSION

Antisense HIF-1alpha blocks tumor hypoxia pathway by downregulating VEGF expression, reduction of vascular density and enhances B7-1-mediated immunotherapy. Strategies that target HIF-1 may have therapeutic potential in cancer treatment and are worthy of further studying.

Pentoxifylline inhibits pulmonary inflammation induced by infrarenal aorticcross-clamping dependent of adenosine receptor A2A

Infrarenal aortic cross-clamping (IAC) is commonly used during infrarenal vascular operations. Prolonged IAC causes ischemia-reperfusion injury to local tissues, resulting in the release of inflammatory cytokines and acute lung injury (ALI). Pentoxifylline (PTX) is a clinically used drug for chronic occlusive arterial diseases and exerts protective effects against ALI induced by various factors in experimental models. In this study, we evaluated the protective effects of PTX in a rat model of IAC. Wistar rats underwent IAC for 2 h, followed by 4 h reperfusion. PTX alone, or in combination with ZM-241385 (an adenosine receptor A2A antagonist) or CGS-21680 (an A2A agonist), was pre-administered to rats 1 h prior to IAC, and the severity of lung injury and inflammation were examined. Administration of PTX significantly attenuated ALI induced by IAC, evidenced by reduced histological scores and wet lung contents, improved blood gas parameters, decreased cell counts and protein amounts in bronchoalveolar lavage fluids, and inhibition of MPO activity and ICAM-1 expression in lung tissues, and lower plasma levels of TNF-α, IL-6, IL-1β and soluble ICAM-1. ZM-241385 significantly abrogated, while CGS-21680 slightly enhanced, the effects of PTX in ameliorating ALI and inhibiting pulmonary inflammation. In exploration of the mechanisms, we found that PTX stimulated IL-10 production through the phosphorylation of STAT3, and A2A receptor participated in this regulation. The study indicates PTX plays a protective role in IAC-induced ALI in rats by inhibiting pulmonary inflammation through A2A signaling pathways.

Disulfiram Synergizes with SRC Inhibitors to Suppress the Growth of Pancreatic Ductal Adenocarcinoma Cells in Vitro and in Vivo

Disulfiram (DSF), an old anti-alcoholism drug, has emerged as a candidate for drug repurposing in oncology. In exploratory studies on its therapeutic effects, we unexpectedly discovered that DSF increased the phosphorylation of SRC, a proto-oncogene tyrosine-protein kinase elevated in 70% of pancreatic ductal adenocarcinoma (PDAC) cases. This serendipitous and novel finding led to our hypothesis for the current study which proposes DSF may synergize with SRC inhibitors in suppressing PDAC. Human PDAC PANC-1 and BXPC-3 cells were incubated with DSF chelated with copper (Cu2+), SRC inhibitors (PP2 and dasatinib), or transfected with lentiviral short hairpin RNA (shRNA), and their proliferation and apoptosis were analyzed. A xenograft model was employed to verify the in vitro results. The expression of key molecules was detected. DSF significantly inhibited cell proliferation and induced cell apoptosis by increasing the cleavage of poly ADP ribose polymerase (PARP), downregulating Bcl-2 and upregulating p27 in concentration- and time-dependent manners. DSF had little effect on signal transducer and activator of transcription 3 (STAT3) expression but inhibited its phosphorylation. DSF did not alter SRC expression but significantly increased its phosphorylation through upregulating actin filament associated protein 1 like 2 (AFAP1L2). DSF exhibited a synergistic effect, as analyzed by drug coefficient interactions, with either PP2, or dasatinib, or SRC depletion in suppressing PDAC cells in vitro and/or in vivo. The present results indicate DSF is a potential therapeutic drug, particularly when it is combined with SRC inhibitors, and warrant further studies on the pharmacological utility of DSF as a promising adjunct therapy for the treatment of PDAC.

[Protection of CSE/H2S system in hepatic ischemia reperfusion injury in rats]

OBJECTIVE

To study the protective function and pathophysiology of cystathionine gamma-lyase (CSE)/hydrogen sulfide (H(2)S) system in hepatic ischemia-reperfusion injury (HIRI) in rats.

METHODS

Wistar rats were randomly distributed into sham group (n = 18), ischemia-reperfusion (IR) group (n = 18), IR + NaHS group (n = 18) and IR + DL-propargylglycine (PAG) group (n = 18). The hepatic IR model was established by Pringle's hepatic vascular occlusion. At each of the indicated time points (1, 3 and 6 hours after IR), the serum levels of H(2)S and the hepatic CSE activity were measured. The serum levels of inflammatory factors, including TNF-α, IL-10 were determined by ELISA methods. The expression of apoptotic protein, TNF-α, in liver tissue was tested by Western blot assay, cell apoptosis was examined by TUNEL and the histological changes were examined in each group.

RESULTS

The serum levels of H(2)S and CSE activity were significantly increased in group IR compared with group sham at all indicated time points (P < 0.05). The serum level of inflammatory factors (P < 0.01) and the hepatic expression of TNF-α protein (P < 0.05) were elevated obviously in group IR than that in group sham. Administration of NaHS could reduce the production of inflammatory factors in serum (P < 0.01), inhibit hepatic protein expression of TNF-α (P < 0.05) and attenuate the liver histological scores of IR injury (P < 0.05), whereas PAG aggravated them.

CONCLUSION

The endogenous CSE/H(2)S system maybe involved in the pathogenesis of hepatic IR injury, which suggests that CSE/H(2)S system can protect liver from IR injury in rats by intervening in inflammatory reaction, attenuating the injury severity and inhibiting expression of apoptotic protein TNF-α.

[Protection of oxymatrine against ischemia-reperfusion injury of liver and mechanism thereof: experiment with rats]

OBJECTIVE

To investigate the effects of oxymatrine on protecting the liver against ischemia-reperfusion injury (IRI) and explore the mechanism thereof.

METHODS

Thirty male Wistar rats were randomly divided into 3 equal groups: IRI group (2 ml normal saline was injected into the dorsal vein of penis, 30 min later laparotomy was performed, arterial clamp was used to grip the hepatic artery and portal vein for 30 minutes and then removed, the vessels were reperfused for 90 min, and 4 ml blood was collected from the aorta; parts of the liver were resected); oxymatrine group (oxymatrine 40 mg/kg was injected into the dorsal vein of penis, and the other procedures were the same as in the IRI group); and sham operation group (2 ml normal saline was injected into the dorsal vein of penis, laparotomy was performed, 150 min after the injection 4 ml blood was collected from the aorta and parts of the liver were resected). The levels of alanine transaminase (ALT) and aspartate transaminase (AST) were detected. The liver tissues underwent HE staining and TUNEL staining for pathological examination. Suspension of single hepatocytes was prepared to observe the ratio of apoptotic cells and cell cycles by flow cytometry (FCM). Western blotting was used to examine the Fas protein expression.

RESULTS

The AST and ALT levels of the IRI group were 1326 U/L +/- 211 U/L and 768 U/L +/- 175 U/L respectively, significantly higher than those of the sham operation group (112 U/L +/- 53 U/L and 55 U/L +/- 17 U/L, both P < 0.05) and those of the oxymatrine group (513 U/L +/- 96 U/L and 352 U/L +/- 72 U/L respectively, both P < 0.01). The liver cells of the sham operation group were normal, those of the IRI group showed remarkable edema and cytoplasm degeneration. TUNEL staining showed remarkably more apoptotic cells in the IRI group. FCM showed that the apoptotic rate of hepatocytes was 42.8% +/- 5.2% in the IRI group, significantly higher than in the oxymatrine group (8.8% +/- 1.8%, P < 0.01), and that the ratio of hepatocytes in G(0)/G(1) stage of the IRI group was 99.2% +/- 1.8%, significantly higher than that of the sham operation group (77.0% +/- 2.1%), and that of the oxymatrine group (87.6% +/- 2.8%) (both P < 0.05); the ratio of hepatocytes in the S stage of the IRI group was 0.52% +/- 0.25%, significantly lower than those of the sham operation group (23.94% +/- 1.84%) and oxymatrine group (12.42% +/- 0.46%) (both P < 0.01). The Fas protein expression was significantly highly in the IRI group than in the oxymatrine group.

CONCLUSION

Remarkably reducing the IRI of hepatocytes, oxymatrine has potential to protect the liver against IRI during surgical intervention.

Mapping the immunological battlefield in gastric cancer: prognostic implications of an immune gene expression signature

BACKGROUND

Gastric cancer (GC) is a heterogeneous malignancy with variable clinical outcomes. The immune system has been implicated in GC development and progression, highlighting the importance of immune-related gene expression patterns and their prognostic significance.

OBJECTIVE

This study aimed to identify differentially expressed immune-related genes (DEIRGs) and establish a prognostic index for GC patients using comprehensive bioinformatic analyses.

METHODS

We integrated RNA sequencing data from multiple databases and identified DEIRGs by overlapping differentially expressed genes with immune-related genes. Functional enrichment analysis was performed to uncover the biological processes and signaling pathways associated with DEIRGs. We conducted a Weighted Gene Co-expression Network Analysis (WGCNA) to identify key gene modules related to with GC. Cox regression analysis was conducted to determine independent prognostic DEIRGs for overall survival prediction. Based on these findings, we developed an immune-related gene prognostic index (IRGPI) based on these findings. The prognostic value of the IRGPI was validated using survival analysis and an independent validation cohort. Functional enrichment analysis, gene mutation analysis, and immune cell profiling were performed to gain insights into the biological functions and immune characteristics associated with the IRGPI-based subgroups.

RESULTS

We identified 493 DEIRGs significantly enriched in immune-related biological processes and signaling pathways associated with GC. WGCNA analysis revealed a significant module (turquoise module) associated with GC, revealing potential therapeutic targets. Cox regression analysis identified RNASE2, CGB5, CTLA4, and DUSP1 as independent prognostic DEIRGs. The IRGPI, incorporating the expression levels of these genes, demonstrated significant prognostic value in predicting overall survival. The IRGPI-based subgroups exhibited distinct biological functions, genetic alterations, and immune cell compositions.

CONCLUSION

Our study identified DEIRGs and established a prognostic index (IRGPI) for GC patients. The IRGPI exhibited promising prognostic potential and provided insights into GC tumor biology and immune characteristics. These findings have implications for guiding therapeutic strategies.

Retraction Notice to: Overexpressed lncRNA GATA6-AS1 Inhibits LNM and EMT via FZD4 through the Wnt/β-Catenin Signaling Pathway in GC

[This retracts the article DOI: 10.1016/j.omtn.2019.09.034.].

Precision medicine for hepatocellular carcinoma: Perspectives and obstacles

Hepatocellular carcinoma (HCC) is one of the most common cancers in China. HCC patients have a poor prognosis due to the lack of effective drugs. The marketing of sorafenib in 2007 has terminated the history that there is no effective drug for HCC. Unfortunately, sorafenib prolongs the survival of advanced HCC patients by only 2-3 mo, and remains the unique systemic drug as no alternative effective agents have been demonstrated to be superior to sorafenib in treating HCC. Precision medicine, a novel concept and medicinal model, has recently emerged and been spreading globally, with the development of gene sequencing techniques, bioinformatics, big data and so on. Detecting, analyzing, verifying and utilizing the specific tumor biomarkers with the advanced technology have made it possible to apply "personalized and precision therapy" in the treatment of advanced HCC. In the present article we summarize the recent progress of HCC therapy under the guidance of precision medicine, and analyze the major obstacles for its clinical application, with an aim to provide some new clues for clinicians and researchers engaged in the clinical and basic research of HCC.

[Gene transfection of endostatin synergizes with doxorubicin to suppress human hepatocellular carcinomas: experiment with mice]

OBJECTIVE

To investigate whether endostatin, a potent antiangiogenic agent, synergizes with doxorubicin to suppress human hepatocellular carcinoma (HCC).

METHODS

An endostatin expression plasmid, Endo-cDNA3.1, was constructed and transfected into COS-1 cells. Human HCC cells of the line HepG2 and human umbilical vein endothelial cells of the line HUVEC were cultured and stimulated by the supernatant of the CoS-1 cells transfected with Endo-pcDNA3.1 and doxorubicin of different concentrations. MTT method was used to detect the proliferation of the cells. (How many) BALB/c mice were inoculated with HepG2 cells to establish HCC models, and then divided into 4 groups to undergo intratumoral injection of pcDNA3.1, End-pcDNA3.1, doxorubicin, or doxorubicin + Endo-pcDNA3.1. Other mice were used as untreated control group. Two weeks later 5 mice from each group were killed with the tumors taken out. Immunostaining was used to calculate the microvessel density and Western blotting was sued to detect the expression of endostatin, hypoxia-inducible factor (HIF) and vascular endothelial growth factor (VEGF).

RESULTS

The proliferation of the HUVEC cells, but not that of the HepG2 cells, transfected with Endo-pcDNA3.1 + doxorubicin was inhibited. Doxorubicin dose-dependently inhibited the proliferation of both HUVEC and HepG2 cells. Endostatin was strongly expressed in the cells treated with Endo-pcDNA3.1 the tumor size of the Endo-pcDNA3.1 and doxorubicin groups were (1545 +/- 180) mm(3) and (953 +/- 250) mm(3) respectively, both significantly lower than that of the untreated and pcDNA3.1 groups [(2360 +/- 330) mm(3) and (2235 +/- 268) mm(3), respectively, all P < 0.01], and the tumor size of the Endo-pcDNA3.1 + doxorubicin group was (426 +/- 87) mm(3), significantly lower than any other groups (all P < 0.01). The number of microvessels of the Endo-pcDNA, doxorubicin, and doxorubicin + Endo-pcDNA3.1 groups were all significantly less than those of the pcDNA3.1 and untreated groups (P < 0.05 or P < 0.01). The expression of HIF-1alphawas downregulated in the Endo-pcDNA3.1 and Endo-pcDNA3.1 + doxorubicin groups, but not in the doxorubicin group. The VEGF expression was down-regulated in the Endo-pcDNA3.1, doxorubicin, and Endo-pcDNA3.1 + doxorubicin groups, especially in the latter.

CONCLUSION

Endostatin gene therapy synergizes with doxorubicin to suppress HCC.

Identification of a novel prognostic model for gastric cancer utilizing glutamine-related genes

BACKGROUND

Glutamine metabolism presents a promising avenue for cancer prevention and treatment, but the underlying mechanisms in gastric cancer (GC) progression remain elusive.

METHODS

The TCGA-STAD and GEO GSE62254 datasets, containing gene expression, clinical information, and survival outcomes of GC, were meticulously examined. Differential expression analysis and weighted gene co-expression network analysis (WGCNA) were employed to excavate a key module (MEturquoise), which was used to intersect with glutamine metabolism-related genes (GMRGs) and differentially expressed genes (DEGs) to identify differentially expressed GMRGs (DE-GMRGs). LASSO and Cox Univariate analyses were implemented to determine risk model genes. Correlation of the risk model with clinical parameters, pathways, and tumor immune microenvironments, was analyzed, and its prognostic independence was validated by Cox analyses. Finally, reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to validate the expression levels of MYB, LRFN4, LMNB2, and SLC1A5 in GC and para-carcinoma tissue.

RESULTS

The excavation of 4521 DEGs led to the discovery of the key MEturquoise module, which exhibited robust correlations with GC traits. The intersection analysis identified 42 DE-GMRGs, among which six genes showed consistency. Further LASSO analysis established MYB, LRFN4, LMNB2, and SLC1A5 as pivotal risk model genes. The risk model demonstrated associations with oncogenic and metabolism-related pathways, inversely correlating with responses to immune checkpoint blockade therapies. This risk model, together with "age", was validated to be an independent prognostic factor for GC. RT-qPCR result indicated that MYB, LRFN4, LMNB2, and SLC1A5 expressions were remarkably up-regulated in GC tissues comparison with para-carcinoma tissue.

CONCLUSION

The present study has generated a novel risk module containing four DE-GMRGs for predicting the prognosis and the response to immune checkpoint blockade treatments for GC. This risk model provides new insights into the involvement of glutamine metabolism in GC, warranting further investigation.

[Construction and activity of recombinant adeno-associated virus expressing vasostatin]

Vasostatin, a 180-amino acid fragment from the N-terminal domain of calreticulin, is a potent endogenous angiogenesis inhibitor, which can inhibit the growth of many kinds of experimental tumor. But a recent report that vasostatin can enhance the malignant behavior of neuroendocrine tumor reminds us to be cautious to develop it as an anti-tumor medicine. VAS cDNA was cloned into pAAV-2 expression vector; recombinant virus rAAV-VAS was generated by a three plasmids, helper free packaging method. MS1 mouse pancreatic endothelial cell and human colon tumor HCT-116 cell were infected with rAAV-VAS. Transgene expression was analyzed by Western blotting analysis; cell proliferation was determined by MTT assay. The therapeutic potential of rAAV-VAS was evaluated in subcutaneous HCT-116 xenograft mouse model. rAAV-VAS inhibited the proliferation of MS1 but not HCT-116 cell. HCT-116 cell infected with rAAV-VAS secreted VAS protein into the supernatant effectively. The intratumoral delivery of rAAV-VAS inhibited the xenograft growth and microvessel density in tumors significantly. Our results show the effectiveness of rAAV-VAS as an angiogenesis inhibitor in suppressing tumor growth, validating the application of rAAV-VAS gene therapy in treatment against colon cancer.

DEAD-Box Helicase 17 circRNA (circDDX17) Reduces Sorafenib Resistance and Tumorigenesis in Hepatocellular Carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is the most common type of liver malignancy. Despite significant progress in HCC treatment, resistance to chemotherapy and tumor metastasis are the main reasons for the unsatisfactory prognosis of HCC. Circular RNAs (circRNAs) have been extensively documented to play a role in the development of various types of cancer.

AIMS

Here, we investigated the role of DEAD-box helicase 17 circRNA (circDDX17) in HCC and its underlying molecular mechanisms.

METHODS

Our research employed various techniques including reverse transcription-quantitative polymerase chain reaction (RT-qPCR), cell counting kit-8 (CCK-8), flow cytometry, dual luciferase reporter assay, RNA immunoprecipitation (RIP), and western blot analysis. Additionally, we conducted a tumor xenograft assay to investigate the in vivo function of circDDX17.

RESULTS

Firstly, the expression of circDDX17 was downregulated in HCC tissues and cells. Through functional experiments, it was observed that the overexpression of circDDX17 enhanced the sensitivity of sorafenib, promoted apoptosis, and inhibited the process of epithelial-mesenchymal transition (EMT) in vitro. Additionally, in vivo studies revealed that circDDX17 reduced tumor growth and increased sorafenib sensitivity. Mechanically, circDDX17 competitively combined miR-21-5p to suppress PTEN expression and activate the PI3K/AKT pathway. Furthermore, our rescue assays demonstrated that circDDX17 act as a tumor suppressor by blocking sorafenib resistance and tumorigenesis, while the inhibitory effect caused by circDDX17 upregulation was neutralized when miR-21-5p was overexpressed, PTEN was silenced, or the PI3K/AKT pathway was activated.

CONCLUSION

Our findings firstly confirmed that circDDX17 suppressed sorafenib resistance and HCC progression by regulating miR-21-5p/PTEN/PI3K/AKT pathway, which may provide novel biomarkers for the diagnosis, treatment and prognosis of HCC.

Is 26S proteasome non-ATPase regulatory subunit 6 a potential molecular target for intrahepatic cholangiocarcinoma?

In this editorial we comment on the article by Tang et al published in the recent issue of World Journal of Hepatology. Drug therapy of intrahepatic cholangiocarcinoma (iCCA) poses an enormous challenge since only a small proportion of patients demonstrate beneficial responses to therapeutic agents. Thus, there has been a sustained search for novel molecular targets for iCCA. The study by Tang et al evaluated the role of 26S proteasome non-ATPase regulatory subunit 6 (PSMD6), a 19S regulatory subunit of the proteasome, in human iCCA cells and specimens. The authors employed clustered regularly interspaced short palindromic repeat (CRISPR) knockout screening technology integrated with the computational CERES algorithm, and analyzed the human protein atlas (THPA) database and tissue microarrays. The results show that PSMD6 is a gene essential for the proliferation of 17 iCCA cell lines, and PSMD6 protein was overexpressed in iCCA tissues without a significant correlation with the clinicopathological parameters. The authors conclude that PSMD6 may play a promoting role in iCCA. The major limitations and defects of this study are the lack of detailed information of CRISPR knockout screening, in vivo experiments, and a discussion of plausible mechanistic cues, which, therefore, dampen the significance of the results. Further studies are required to verify PSMD6 as a molecular target for developing novel therapeutics for iCCA. In addition, the editorial article summarizes the latest advances in molecular targeted drugs and recently emerging immunotherapy in the clinical management of iCCA, development of proteasome inhibitors for cancer therapy, and advantages of CRISPR screening technology, computational methods, and THPA database as experimental tools for fighting cancer. We hope that these comments may provide some clues for those engaged in the field of basic and clinical research into iCCA.

Distribution of glutathione peroxidase-1 immunoreactive cells in pancreatic islets from type 1 diabetic donors and non-diabetic donors with and without islet cell autoantibodies is variable and independent of disease

During type 1 diabetes (T1D), oxidative stress in beta cells may cause early beta cell dysfunction and initiate autoimmunity. Mouse islets express lower levels of reactive oxygen species (ROS) clearing enzymes, such as glutathione peroxidase (GPX), superoxide dismutase (SOD) and catalase than several other tissues. It remains unclear if human beta cells show a similar deficiency during T1D or exhibit a higher degree of intrinsic resistance to oxidative stress. We compared islet cell distributions and determined graded intensities of glutathione peroxidase1 (GPX1), a key enzymatic mediator involved in detoxifying hydrogen peroxide, by applying combined immunohistochemistry for GPX1, insulin and glucagon, in pancreatic sections from new-onset T1D (group 1), non-diabetic autoantibody-negative (group 2), non-diabetic autoantibody-positive (group 3) and long-term diabetic (group 4) donors. Islets from all study groups demonstrated either uniform but graded staining intensities for GPX1 in almost all islet cells or strong staining in selective islet cells with weaker intensities in the remaining cells. GPX1 was present in selective glucagon cells and insulin cells, including in cells negative for both hormones, with stronger intensities in a higher percentage of glucagon than insulin cells. It was absent in a higher percentage of beta cells than glucagon cells independent of disease or autoantibody positivity. We conclude that a proportion of human beta cells and glucagon cells express GPX1 but show heterogeneity in its distribution and intensities, independent of disease or autoantibody status. Our studies highlight important differences in the expression of GPX1 in islet cell-types between mice and humans.

[Corrigendum] T7 peptide inhibits angiogenesis via downregulation of angiopoietin‑2 and autophagy

Following the publication of this article, an interested reader drew to the authors' attention that two pairs of protein bands featured in the western blots in Fig. 3A and 5D on p. 679 and 681 respectively appeared to be strikingly similar. After having re‑examined their original data, the authors realized that Fig. 5D had been assembled incorrectly. The revised version of Fig. 5, now including the correct data for Fig. 5D, is shown on the next page. Note that the errors made in terms of assembling the data in Fig. 5 did not greatly affect either the results or the conclusions reported in this paper, and all the authors agree to the publication of this corrigendum. The authors regret that these errors went unnoticed prior to the publication of their article, are grateful to the Editor of Oncology Reports for allowing them this opportunity to publish this corrigendum. They also apologize to the readership for any inconvenience caused. [Oncology Reports  33: 675‑684, 2015; DOI: 10.3892/or.2014.3653].