CHIP/Stub1 regulates the Warburg effect by promoting degradation of PKM2 in ovarian carcinoma

Tumor cells preferentially adopt aerobic glycolysis for their energy supply, a phenomenon known as the Warburg effect. It remains a matter of debate as to how the Warburg effect is regulated during tumor progression. Here, we show that CHIP (carboxyl terminus of Hsc70-interacting protein), a U-box E3 ligase, suppresses tumor progression in ovarian carcinomas by inhibiting aerobic glycolysis. While CHIP is downregulated in ovarian carcinoma, induced expression of CHIP results in significant inhibition of the tumor growth examined by in vitro and in vivo experiments. Reciprocally, depletion of CHIP leads to promotion of tumor growth. By a SiLAD proteomics analysis, we identified pyruvate kinase isoenzyme M2 (PKM2), a critical regulator of glycolysis in tumors, as a target that CHIP mediated for degradation. Accordingly, we show that CHIP regulates PKM2 protein stability and thereafter the energy metabolic processes. Depletion or knockout of CHIP increased the glycolytic products in both tumor and mouse embryonic fibroblast cells. Simultaneously, we observed that CHIP expression inversely correlated with PKM2 levels in human ovarian carcinomas. This study reveals a mechanism that the Warburg effect is regulated by CHIP through its function as an E3 ligase, which mediates the degradation of PKM2 during tumor progression. Our findings shed new light into understanding of ovarian carcinomas and may provide a new therapeutic strategy for ovarian cancer.

[Relationship between obstructive sleep apnea syndrome and cognitive impairment and functional status after stroke]

Objective:To analyze the correlation between obstructive sleep apnea syndrome (OSAHS) and cognitive impairment and functional status after stroke. Method:From February 2014 to September 2016, a total of 189 patients were included in the study, 33 patients with mild OSAHS were excluded, and finally 86 patients in the study group and 70 patients in the control group were included in the final analysis. The main indicators included the cognitive and functional status. Cognitive status was assessed by nine dimensions: vigilance, attention, memory, working memory, executive, language, insight, mental activity, psychomotor, and intelligence. Functional status was assessed using neurological status and functional independence. Secondary measures included sleepiness, fatigue, anxiety and depression, and sleep quality. Result:The age of the study group was higher than the control group, the BMI was higher than the control group, the average hospitalization time was longer than the control group, and all of the difference were statistically significant (all P<0.05). The total cognitive status of the two groups was significantly different, and the total cognitive status study group was significantly worse than in the control group (t=9.276, P=0.012). In the nine dimensions of cognitive ability, the study group's attention, execution, insight, mental adjustment and intelligence were lower than the control group, and the difference was statistically significant (P<0.05). The functional status of the study group was worse than that of the control group (t=38.094, P=0.000). There were no significant differences between the two groups in terms of sleepiness, fatigue, sleep quality, anxiety and depression (P>0.05). Conclusion:The cognitive impairment and functional status of stroke patients with OSAHS are significantly worse. OSAHS is a risk factor for poor prognosis in stroke patients.

Etoposide and cisplatin versus paclitaxel and carboplatin with concurrent thoracic radiotherapy in unresectable stage III non-small cell lung cancer: a multicenter randomized phase III trial

Background

The optimal chemotherapy regimen administered currently with radiation in patients with stage III non-small cell lung cancer (NSCLC) remains unclear. A multicenter phase III trial was conducted to compare the efficacy of concurrent thoracic radiation therapy with either etoposide/cisplatin (EP) or carboplatin/paclitaxel (PC) in patients with stage III NSCLC.

Patients and methods

Patients were randomly received 60-66 Gy of thoracic radiation therapy concurrent with either etoposide 50 mg/m2 on days 1-5 and cisplatin 50 mg/m2 on days 1 and 8 every 4 weeks for two cycles (EP arm), or paclitaxel 45 mg/m2 and carboplatin (AUC 2) on day 1 weekly (PC arm). The primary end point was overall survival (OS). The study was designed with 80% power to detect a 17% superiority in 3-year OS with a type I error rate of 0.05.

Results

A total of 200 patients were randomized and 191 patients were treated (95 in the EP arm and 96 in the PC arm). With a median follow-up time of 73 months, the 3-year OS was significantly higher in the EP arm than that of the PC arm. The estimated difference was 15.0% (95% CI 2.0%-28.0%) and P value of 0.024. Median survival times were 23.3 months in the EP arm and 20.7 months in the PC arm (log-rank test P = 0.095, HR 0.76, 95%CI 0.55-1.05). The incidence of Grade ≥2 radiation pneumonitis was higher in the PC arm (33.3% versus 18.9%, P = 0.036), while the incidence of Grade ≥3 esophagitis was higher in the EP arm (20.0% versus 6.3%, P = 0.009).

Conclusion

EP might be superior to weekly PC in terms of OS in the setting of concurrent chemoradiation for unresectable stage III NSCLC.

Trial registration ID

NCT01494558.

[Mutation status of epidermal growth factor receptor and KRAS gene in non-small cell lung cancers at Xuanwei regions of Yunnan Province]

OBJECTIVE

To investigate the mutation status of epidermal growth factor receptor (EGFR) and KRAS gene in patients with non-small cell lung cancer (NSCLC) in Xuanwei, Yunnan and to correlate the mutation status with clinicopathologic features.

METHODS

Mutation status of exons 18, 19, 20 and 21 of EGFR, and codons 12, 13 of KRAS in 63 cases of NSCLC were analyzed by gene sequencing and ARMS-Taqman probe method. Correlation with patients' clinicopathological characteristics was performed.

RESULTS

EGFR and KRAS mutations were present in 55.6% (35/63) and 6.3% (4/63), respectively. EGFR gene mutations were present, including exon 18 G719X in 14.3% (5/35), exon 19 in 14.3% (5/35), exon 20 S768I and T790M in 20.0% (7/35), exon 21 L858R in 31.4% (11/35), exon 18 G719X and exon 20 S768I double mutation in 17.1% (6/35), and exon 20 T790M and exon 21 L858R double mutation in 2.9% (1/35). KRAS mutations were seen in codon 12 in 3 of 4 cases, and codon 13 in 1 of 4 cases. EGFR mutations were mutually exclusive with KRAS mutations. According to statistic analysis, EGFR mutations were associated with the histological types of NSCLC(P<0.05), but without correlation with patient's gender, age, smoking status and lymph node metastasis(P>0.05). KRAS mutations in NSCLC had no correlation with the clinical pathologic characteristics of the patients.

CONCLUSIONS

A higher frequency of EGFR exon 18 G719X and 20 exon S768I mutations are found in the patients in Xuanwei, Yunnan. EGFR mutations are associated with histologic types of NSCLC, but without correlation with patient's gender, age, smoking status and lymph node metastasis. KRAS mutation in NSCLC has no correlation with the clinicopathologic characteristics of the patients.

The antitumor efficacy of anti-p21Ras scFv mediated by the dual-promoter-regulated recombinant adenovirus KGHV300

Ras mutations and overexpression of the Ras protein, p21Ras, are main causes of cancer development and progression, which has made the Ras gene and p21Ras important targets for therapy of Ras-driven cancers. We previously prepared recombinant adenovirus KGHV100 based on replication-defective adenovirus type 5, which could intracellularly express anti-p21Ras single chain fragment viable antibodies (scFv) and repress tumor growth in vitro and in vivo. However, the anti-tumor effects of this anti-p21Ras scFv were limited by short-term scFv expression due to a replication defect of KGHV100. To enhance the anti-tumor efficacy and safety of anti-p21Ras scFv, the present study constructed a dual-promoter-regulated recombinant adenovirus KGHV300 that carried anti-p21Ras scFv. In KGHV300, the expression levels of the essential replication genes E1a and E1b, were controlled by the human telomerase reverse transcriptase promoter and the hypoxia response element, respectively, and the anti-p21Ras scFv gene was controlled by the cytomegalovirus promoter. The conditional replication of KGHV300 and its antitumor efficacy were characterized in several tumor cell lines in vitro and in xenograft models of human breast cancer in nude mice. TCID50 assay demonstrated that KGHV300 could replicate in tumor cell lines but not in normal cell lines. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay indicated that the growth of tumor cells was effectively inhibited by KGHV300 infection. In MDA-MB-231 tumor xenograft models, KGHV300 effectively and significantly inhibited tumor growth and induced apoptosis of tumor cells. We concluded that the recombinant adenovirus KGHV300 may be a more potent and safer antitumor therapeutic for Ras-driven cancer biotherapy.

Meta-analysis of genome-wide association studies of HDL cholesterol response to statins

BACKGROUND

In addition to lowering low density lipoprotein cholesterol (LDL-C), statin therapy also raises high density lipoprotein cholesterol (HDL-C) levels. Inter-individual variation in HDL-C response to statins may be partially explained by genetic variation.

METHODS AND RESULTS

We performed a meta-analysis of genome-wide association studies (GWAS) to identify variants with an effect on statin-induced high density lipoprotein cholesterol (HDL-C) changes. The 123 most promising signals with p<1×10-4 from the 16 769 statin-treated participants in the first analysis stage were followed up in an independent group of 10 951 statin-treated individuals, providing a total sample size of 27 720 individuals. The only associations of genome-wide significance (p<5×10-8) were between minor alleles at the CETP locus and greater HDL-C response to statin treatment.

CONCLUSIONS

Based on results from this study that included a relatively large sample size, we suggest that CETP may be the only detectable locus with common genetic variants that influence HDL-C response to statins substantially in individuals of European descent. Although CETP is known to be associated with HDL-C, we provide evidence that this pharmacogenetic effect is independent of its association with baseline HDL-C levels.

Artificial cartilage bio-matrix formed of hyaluronic acid and Mg2+-polyphosphate

Here we show that inorganic polyphosphate (polyP), a polyanionic metabolic regulator consisting of multiple phosphate residues linked by energy-rich phosphoanhydride bonds, is present in the synovial fluid. In a biomimetic approach, to enhance cartilage synthesis and regeneration, we prepared amorphous polyP microparticles with Mg2+ as counterions. The particles were characterised by X-ray diffraction (XRD), energy-dispersive X-ray (EDX) and Fourier transformed infrared spectroscopic (FTIR) analyses. Similar particles were obtained after addition of Mg2+ ions to a solution containing hyaluronic acid, as a major component of the synovial fluid, and soluble Na-polyP. The viscous paste-like material formed, composed of globular microparticles with diameter of 400 nm, strongly promoted the adhesion of chondrocytes and caused a significant upregulation of the expression of the genes encoding collagen type 3A1, as a marker for chondrocyte differentiation, and SOX9, a transcription factor that regulates chondrocyte differentiation and proliferation. The expression level of the collagen type 3A1 gene was also enhanced by exposure of chondrocytes to synovial fluid that was found to contain polyP with a size of about 80 phosphate residues. This stimulatory effect was abolished after pre-incubation of the synovial fluid with the polyP degrading alkaline phosphatase. We propose a strategy for treatment of joint dysfunctions caused by osteoarthritis based on the application of amorphous Mg2+-polyP microparticles thatprevent calcium crystal formation in the synovial fluid using scavenging Ca2+ ions (Mg2+/Ca2+ exchange) and enhance chondrocyte function after binding of the Ca2+-polyP to hyaluronic acid at the cartilage surface.

[Expression of epidermal growth factor receptor mutation specific antibodies in lung adenocarcinoma: evaluation of sensitivity, specificity and relationship to histologic subtypes]

OBJECTIVE

To evaluate the expression of epidermal growth factor receptor (EGFR) mutation specific antibodies in invasive lung adenocarcinomas, and their sensitivity, specificity, as well as relationship to histological subtypes.

METHODS

Immunostaining with EGFR mutation-specific antibodies, del E746-A750 in exon 19 and L858R in exon 21, was performed in tissue microarrays of 884 cases of resection specimens to study the relationship between the immunophenotypes and morphologic subtypes. The sensitivity and specificity of the stains were compared with gene mutations detected by amplified refractory mutation system-polymerase chain reaction (ARMS-PCR).

RESULTS

Of the 884 cases, the expression of del E746-A750 in exon 19 was 3+ , 2+ , 1+ and 0 in 7 cases (0.79%), 38 cases (4.30%), 129 cases (14.59%) and 710 cases (80.32%), respectively. For L858R in exon 21, 3+ , 2+ , 1+ and 0 staining were seen in 82 cases (9.28%), 93 cases (10.52%), 82 cases (9.28%) and 627 cases (70.93%), respectively. For both antibodies, positive expression (1+ or more) was mainly observed in lepidic, acinar and papillary predominant subtypes, and rarely seen in solid subtype or invasive mucinous adenocarcinoma (P=0.014 and 0.016). If 1+ to 3+ expression was set as positive, the specificity of exon 19/exon 21 reached 98.59%/92.98%, while the sensitivity was relatively lower (62.86%/88.89%). If 2+ to 3+ expression was read as positive, the specificity and sensitivity were 99.30%/97.37% and 25.71%/74.60% for exon 19/exon 21. If only 3+ expression was considered positive, the specificity was 100.0% for both antibodies, with a low sensitivity (8.57% for exon 19 and 34.92% for exon 21). Of the 18 cases with E746-A750 del in exon 19 based on molecular detection, the sensitivity of immunohistochemistry for exon 19 was 88.89% if a positive cutoff value ≥1+ was used; in contrast, of the 8 cases harboring other deletions in exon 19, only two cases were positive as 1+ .

CONCLUSIONS

Both the EGFR mutation specific antibodies del E746-A750 in exon 19 and L858R in exon 21 demonstrate high specificity and relatively low sensitivity, and are mostly expressed in lepidic, acinar and papillary predominant subtypes, but rarely in solid subtype or invasive mucinous adenocarcinoma. For cases with 3+ expression, a mutational statue for EGFR is likely. For the 2+ positive cases, the accuracy to predict mutation almost reaches 90%, but molecular detection for confirmation is desirable. For the 1+ and negative cases, DNA-based test is essential to avoid false negativity.

Effect of miR-29c and miR-129-5p on epithelial-mesenchymal transition in experimental biliary atresia mouse models

Biliary atresia (BA) is a destructive bile duct disease occurring in newborn children within a few weeks after birth. In this study, the effect of miR-29c and miR-129-5p on epithelial-mesenchymal transition (EMT) in experimental BA was explored by constructing BA mouse models via Rhesus rotavirus vaccine infection. miR-29c and miR-129-5p expression was analyzed by real-time quantitative polymerase chain reaction. EMT was established by induction with transforming growth factor (TGF)-β1. miR-29c and miR-129-5p were overexpressed and inhibited, respectively, by Lipofectamine transfection. EMT-related protein (formin-like 2, FMNL2; E-cadherin; vimentin; and cytokeratin-19, CK-19) expression was analyzed by western blot and immunofluorescent assay. The results indicated that miR-29c and miR-129-5p were downregulated and upregulated in BA mice. TGF-β1 induction caused a time-dependent decrease and increase in miR-29c and miR-129-5p, respectively. Additionally, TGF-β1 induced an increase in FMNL2 and vimentin expression and a decrease in E-cadherin and CK-19 expression (P < 0.05). Overexpression or suppression of miRNA-29c or miR-129-5p, respectively, induced the inhibition of FMNL2 and vimentin, and promotion of E-cadherin and CK-19 expression, in the test groups compared to the non-intervention group (P < 0.05). However, the FMNL2, vimentin, E-cadherin, and CK- 19 expression did not differ between the control and non-intervention groups (P > 0.05). Thus, miR-29c upregulation or miR-129-5p downregulation effectively prevented EMT in BA by regulating the expression of EMT pathway-related proteins. Therefore, miR-29c and miR-129-5p could be utilized as therapeutic targets for BA in the future.

Increased survivin expression and its association with clinical parameters of congenital choledochal cysts

The aim of the current study was to investigate survivin expression in congenital choledochal cysts (CCCs), and its associations with clinical parameters of CCCs. In total, 121 children with CCCs were included in this study as the case group, and their cysts were staged according to the Todani classification system. Additionally, 49 normal gallbladder specimens from healthy children were included as the control group. Survivin detection was conducted using immunohistochemical staining. Associations between positive survivin expression and clinical parameters of CCCs were then analyzed. Positive survivin expression was observed in the cytoplasm, and was seen as granular with yellow or dark brown staining. In the case group, positive survivin expression was detected in most tissues. Specifically, compared to that of normal tissues, the cystic-shaped and fusiform-shaped CCC tissues had significantly higher positive survivin expression rates (all P < 0.05). Importantly, positive survivin expression was also shown to be significantly associated with gender and histological type (both P < 0.05). In conclusion, increased survivin expression was observed in CCC tissues, and was correlated with certain clinical parameters of CCCs, suggesting a possible prognostic value of survivin for CCC progression.

Self-assembled fibrillar networks comprised of a naturally-occurring cyclic peptide—LOB3

LOB3, a naturally-occurring orbitide, is capable of self-assembling into 1D nano-fibers and ultimately 3D molecular gel networks in acetonitrile.

Identification of molecular markers related to human alveolar bone cells and pathway analysis in diabetic patients

Alveolar bone osteoblasts are widely used in dental and related research. They are easily affected by systemic diseases such as diabetes. However, the mechanism of diabetes-induced alveolar bone absorption remains unclear. This study systematically explored the changes in human alveolar bone cell-related gene expression and biological pathways, which may facilitate the investigation of its mechanism. Alveolar bone osteoblasts isolated from 5 male diabetics and 5 male healthy adults were cultured. Total RNA was extracted from these cells and subjected to gene microarray analysis. Differentially expressed genes were screened, and a gene interaction network was constructed. An enrichment pathway analysis was simultaneously performed on differentially expressed genes to identify the biological pathways associated with changes in the alveolar bone cells of diabetic humans. In total, we identified 147 mRNAs that were differentially expressed in diabetic alveolar bone cells (than in the normal cells; 91 upregulated and 36 downregulated mRNAs). The constructed co-expression network showed 3 pairs of significantly-expressed genes. High-enrichment pathway analysis identified 8 pathways that were affected by changes in gene expression; three of the significant pathways were related to metabolism (inositol phosphate metabolism, propanoate metabolism, and pyruvate metabolism). Here, we identified a few potential genes and biological pathways for the diagnosis and treatment of alveolar bone cells in diabetic patients.