Muscle-specific overexpression of Atg2 gene and endurance exercise delay age-related deteriorations of skeletal muscle and heart function via activating the AMPK/Sirt1/PGC-1α pathway in male Drosophila.

Atg2 is a key gene in autophagy formation and plays an important role in regulating aging progress. Exercise is an important tool to resist oxidative stress in cells and delay muscle aging. However, the relationship between exercise and the muscle Atg2 gene in regulating skeletal muscle aging remains unclear. Here, overexpression or knockdown of muscle Atg2 gene was achieved by constructing the AtgUAS/MhcGal4 system in Drosophila, and these flies were also subjected to an exercise intervention for 2 weeks. The results showed that both overexpression of Atg2 and exercise significantly increased the climbing speed, climbing endurance, cardiac function, and lifespan of aging flies. They also significantly up-regulated the expression of muscle Atg2, AMPK, Sirt1, and PGC-1α genes, and they significantly reduced muscle malondialdehyde and triglyceride. These positive benefits were even more pronounced when the two were combined. However, the effects of Atg2 knockdown on skeletal muscle, heart, and lifespan were reversed compared to its overexpression. Importantly, exercise ameliorated age-related changes induced by Atg2 knockdown. Therefore, current results confirmed that both overexpression of muscle Atg2 and exercise delayed age-related deteriorations of skeletal muscle, the heart function, and lifespan, and exercise could also reverse age-related changes induced by Atg2 knockdown. The molecular mechanism is related to the overexpression of the Atg2 gene and exercise, which increase the activity of the AMPK/Sirt1/PGC-1α pathway, oxidation and antioxidant balance, and lipid metabolism in aging muscle.

Changes in the intestinal microbiota of patients with Parkinson's disease and their clinical significance.

OBJECTIVE: To investigate the differences and their clinical significance in the intestinal microbiota in patients with Parkinson's disease (PD) in comparison to those in healthy controls. MATERIALS AND METHODS: 20 patients with PD who received treatment in the First Affiliated Hospital of Bengbu Medical College between January 2019 and December 2019 were selected as the research subjects to form the PD group, while 20 age- and gender-matched healthy volunteers were selected as the control group. Fecal samples from the two groups were collected, and the V4 region of 16S-ribosomal ribonucleic acid was selected for high-throughput sequencing analysis to explore any differences, as well as their significance, in the intestinal microbiota abundance at the class, family, and genus levels between the two study groups. RESULTS: The operational taxonomic unit cluster analysis revealed a high degree of overlap between the patients with PD and the controls. Compared with the controls, the relative abundance of Coriobacteriia and Coriobacteriaceae was increased in the PD group (p < 0.01), while the relative abundance of Lachnospiraceae was significantly lower (p < 0.01). The relative abundance of Collinsella, Escherichia, and Fusobacterium in the PD group was significantly higher than in the control group (p < 0.05). CONCLUSION: Compared with the healthy subjects, the abundance of specific microflora was significantly different in the PD patients at the class, family, and genus level. Intestinal flora may act as a potential biomarker for PD and provide a theoretical basis for microflora transplantation therapy.

Proposal of a new T-stage classification system for ampullary carcinoma based on Surveillance, Epidemiology and End Result (SEER) database.

BACKGROUND: Tumor size is still considered a useful prognostic factor in currently available tumor-node-metastasis (TNM) classification staging systems for most solid tumors, but the significance of tumor size on the prognosis of ampullary carcinoma remains controversial. The aim of the current study was to propose a new T-stage classification system for ampullary carcinoma to address the impact of tumor size on the prognostic outcome. METHODS: Using the Surveillance, Epidemiology, and End Results (SEER) database, we identified 1080 patients with ampullary carcinoma who underwent radical surgical resection between 2004 and 2015. Based on the results obtained from analysis of various clinicopathologic factors, a new T-stage classification system was proposed. RESULTS: Among the 1080 patients, 618 were men and 462 were women, with a median tumor size of 2.3 (range 0.1-12) cm. Using the 7th edition of the American Joint Committee on Cancer (AJCC) staging manual, we noticed significant differences in overall survival (OS) between T2 vs. T3 tumors (P < 0.001) and T3 vs. T4 tumors (P = 0.002), but failed to observe significant differences between T1 vs. T2 tumors (P = 0.498) in our pair-wise comparison. Using the newly developed T-stage classification system, we were able to differentiate significant differences in OS between T1 vs. T2 tumors (P = 0.032), T2 vs. T3 tumors (P < 0.001) and T3 vs. T4 tumor (P = 0.003) in all pair-wise comparisons. The c-index of the new staging system was 0.653 (95% CI: 0.629-0.677), showing a better discriminatory power than the 0.636 of the 7th AJCC staging system (95% CI: 0.612-0.660). CONCLUSIONS: The new T-stage classification system described herein can better differentiate prognostic outcomes after radical resection in patients with ampullary carcinoma by incorporating tumor size and depth of tumor infiltration.

The Complete Mitochondrial Genome of Lepidotrigona flavibasis (Hymenoptera: Meliponini) and High Gene Rearrangement in Lepidotrigona Mitogenomes.

We reported the sequence and characteristics of the complete mitochondrial genome of an ecologically important stingless bee, Lepidotrigona flavibasis (Hymenoptera: Meliponini), that has suffered serious population declines in recent years. A phylogenetic analysis based on complete mitogenomes indicated that L. flavibasis was first clustered with another Lepidotrigona species (L. terminata) and then joined with the other two Melipona (Hymenoptera: Meliponini) stingless bees (M. scutellaris and M. bicolor), forming a single clade of stingless bees. The stingless bee clade has a closer relationship with bumblebees (Bombus) (Hymenoptera: Apidae) than with honeybees (Apis) (Hymenoptera: Apidae). Extremely high gene rearrangements involving tRNAs, rRNAs, D-loop regions, and protein-coding genes were observed in the Lepidotrigona mitogenomes, suggesting an overactive evolutionary status in Lepidotrigona species. These mitogenomic organization variations could provide a good system with which to understand the evolutionary history of Meliponini.

CRISPR-Cas-mediated gene editing in lactic acid bacteria.

The high efficiency, convenience and diversity of clustered regular interspaced short palindromic repeats (CRISPR)/CRISPR-associated (Cas) systems are driving a technological revolution in the gene editing of lactic acid bacteria (LAB). Cas-RNA cassettes have been adopted as tools to perform gene deletion, insertion and point mutation in several species of LAB. In this article, we describe the basic mechanisms of the CRISPR-Cas system, and the current gene editing methods available, focusing on the CRISPR-Cas models developed for LAB. We also compare the different types of CRISPR-Cas-based genomic manipulations classified according to the different Cas proteins and the type of recombineering, and discuss the rapidly evolving landscape of CRISPR-Cas application in LAB.

Short communication: Dynamic changes in bacterial diversity during the production of powdered infant formula by PCR-DGGE and high-throughput sequencing.

Microorganisms such as thermophilic and psychrotrophic bacteria cause spoilage of milk and milk products [e.g., powdered infant formula (PIF)], mainly because they produce heat-stable extracellular enzymes. However, the dynamic changes in microbial diversity during PIF production are still not well understood. We used denaturing gradient gel electrophoresis (DGGE) and high-throughput sequencing (HTS) to investigate bacterial community structure and distribution during the major stages of PIF production: raw milk, pasteurization, mixing, evaporation, and spray-drying. Our PCR-DGGE analysis indicated that Lactobacillus and Pseudomonas spp. were the dominant bacteria at the raw milk and pasteurization stages; Lactococcus, Streptococcus, Enterococcus, and Lactobacillus spp. were abundant during mixing, evaporation, and spray-drying. Our HTS analysis showed that Pseudomonas had an abundance of 96.79% at the raw milk stage. Lactobacillus, Streptococcus, Thermus, Acinetobacter, and Bacteroides spp. were most common after pasteurization. The index of bacterial diversity was highest at the evaporation stage, suggesting a high potential risk of microbial contamination. The results from DGGE and HTS were consistent in reflecting changes in dominant flora, but different in reflecting the richness of bacterial communities present during PIF production: HTS revealed a much higher richness of bacterial species than DGGE. Our findings from DGGE and HTS showed that psychrophilic and thermophilic bacteria were the main flora present during PIF production: psychrophilic bacteria were mainly Pseudomonas spp. and thermophilic bacteria were mainly Lactobacillus, Streptococcus, and Bacillus spp. To our knowledge, this is the first study to report dynamic changes in microbial communities during PIF production. Our results provide insight into bacterial communities and identify potential contamination sources that could serve as a guide for reducing microbial risk.

Comparison of gal-lac operons in wild-type galactose-positive and -negative Streptococcus thermophilus by genomics and transcription analysis.

Streptococcus thermophilus is one of the most important homo-fermentative thermophilic bacteria, which is widely used as a starter culture in dairy industry. Both wild-type galactose-negative (Gal-) S. thermophilus AR333 and galactose-positive (Gal+) S. thermophilus S-3 in this study were isolated from Chinese traditional dairy products. Here, to access the mechanism of the difference of galactose utilization between strains AR333 and S-3, the expression of gal-lac operons was examined using real-time qPCR in the presence of different sugars, and the gene organization of gal-lac operons was characterized using comparative genomics analysis. As compared with medium containing glucose, the expression of gal-lac operons in AR333 and S-3 was significantly activated (> 5-fold) in the presence of galactose or lactose in the medium. More importantly, the expression of gal operon in S-3 was higher than that of AR333, suggesting that the strength of gal promoter in AR333 and S-3 may be different. The genomes of AR333 and S-3 were the first time sequenced to provide insight into the difference of gal-lac operons in these two strains. Comparative genomics analysis showed that gene order and individual gene size of gal-lac operons are conserved in AR333 and S-3. The DNA sequence of gal operon responsible for galactose utilization between AR333 and S-3 is almost identical except that galK promoter of S-3 possesses single base pair mutation (G to A substitution) at -9 box galK region. Moreover, the expression of red fluorescent protein can be activated by galK promoter of S-3, but cannot by galK promoter of AR333 in galactose medium, suggesting that gal operon is silent in AR333 and active in S-3 under galactose-containing medium. Overall, our results indicated that single point mutation at -9 box in the galK promoter can significantly affect the expression of gal operon and is largely responsible for the Gal+ phenotype of S. thermophilus.

Long-term outcomes of combined hepatocellular-cholangiocarcinoma after hepatectomy or liver transplantation: A systematic review and meta-analysis.

BACKGROUND: Combined hepatocellular-cholangiocarcinoma (cHCC-CC) is a rare primary liver malignancy. We conducted a systematic review and meta-analysis to assess the evidence available on the long-term outcomes of cHCC-CC patients after either hepatectomy or liver transplantation (LT). DATA SOURCES: Relevant studies published between January 2000 and January 2018 were identified by searching PubMed and Embase and reviewed systematically. Data were pooled using a random-effects model. RESULTS: A total of 42 observational studies involving 1691 patients (1390 for partial hepatectomy and 301 for LT) were included in the analysis. The median tumor recurrence and 5-year overall survival (OS) rates were 65% (range 38%-100%) and 29% (range 0-63%) after hepatectomy versus 54% (range 14%-93%) and 41% (range 16%-73%) after LT, respectively. Meta-analysis found no significant difference in OS and tumor recurrence between LT and hepatectomy groups. CONCLUSION: Hepatectomy rather than LT should be considered as the prior treatment option for cHCC-CC.

Survival after repeat hepatectomy for recurrent colorectal liver metastasis: A review and meta-analysis of prognostic factors.

BACKGROUND: Frequent recurrent hepatic metastasis after hepatic metastasectomy is a major obstacle in the treatment of colorectal liver metastasis (CRLM). We performed the present systematic review to evaluate the short- and long-term outcomes after repeat hepatectomy for recurrent CRLM and determine factors associated with survival in these patients. DATA SOURCES: An electronic search of PubMed database was undertaken to identify all relevant peer-reviewed papers published in English between January 2000 and July 2018. Hazard ratios (HR) with 95% confidence interval (95% CI) were calculated for prognostic factors of overall survival (OS). RESULTS: The search yielded 34 studies comprising 3039 patients, with a median overall morbidity of 23% (range 8%-71%), mortality of 0 (range 0-6%), and 5-year OS of 42% (range 17%-73%). Pooled analysis showed that primary T3/T4 stage tumor (HR = 1.94; 95% CI: 1.04-3.63), multiple tumors (HR = 1.49; 95% CI: 1.10-2.01), largest liver lesion ≥5 cm (HR = 1.89; 95% CI: 1.11-3.23) and positive surgical margin (HR = 1.80; 95% CI: 1.09-2.97) at initial hepatectomy, and high serum level of carcinoembryonic antigen (HR = 1.87; 95% CI: 1.27-2.74), disease-free interval ≤12 months (HR = 1.34; 95% CI: 1.10-1.62), multiple tumors (HR = 1.64; 95% CI: 1.32-2.02), largest liver lesion ≥5 cm (HR = 1.85; 95% CI: 1.34-2.56), positive surgical margin (HR = 2.25; 95% CI: 1.39-3.65), presence of bilobar disease (HR = 1.62; 95% CI: 1.19-2.20), and extrahepatic metastases (HR = 1.60; 95% CI: 1.23-2.09) at repeat hepatectomy were significantly associated with poor OS. CONCLUSIONS: Repeat hepatectomy is a safe and effective therapy for recurrent CRLM. Long-term outcome is predicted mainly by factors related to repeat hepatectomy.

Formaldehyde inhalation triggers autophagy in rat lung tissues.

Formaldehyde (FA), a ubiquitous environmental contaminant, has long been suspected of causing lung injury. However, the molecular and cellular mechanisms underlying this phenomenon remain elusive. The aim of this study was to elucidate the role of autophagy in lung injury induced by FA inhalation. In this study, lung weight coefficient, interleukin 8 in bronchoalveolar fluid, and histopathological examination were used to evaluate the lung injury. Moreover, electron microscopy, Western blotting for the ratio of LC3-II/LC3-I were used to detect autophagy in lung tissues. Our results indicated that the lung toxicity of FA inhalation is dose dependent. Lung weight coefficient, inflammatory response, and histopathological structure in the 0.5 mg/m3 FA exposure group showed no obvious changes compared with the control. However, exposure to 5 and 10 mg/m3 FA produced lung injury including pulmonary edema, histological changes, and inflammatory responses. Furthermore, the alterations of autophagy correlated with lung injury. Taken together, these data indicate that FA exposure triggers autophagy of alveolar epithelial cells, which might play a pivotal role in lung injury.

Pressure induced topological phase transition in layered Bi2S3.

A large bulk band gap and tunable Dirac carriers are desired for practical device applications of topological insulators. However, most known topological insulators are narrow gap materials and the manipulation of their Dirac surface states is limited by residual bulk charge carriers originating from intrinsic defects. In this study, via density functional theory based first-principles calculations, we predict that a layered hexagonal structure of Bi2S3 is stable, and it becomes a topological insulator under a moderate compressive pressure of about 5.3 GPa. Interestingly, we find that the strength of the spin-orbit interaction in Bi2S3 can be effectively enhanced by the applied pressure. This leads to an increased inverted band gap with pressure, which can reach 0.4 eV with a pressure of 13.7 GPa. Compared to Bi2Se3, intrinsic defects are suppressed in Bi2S3 under both cation- and anion-poor growth conditions. Our calculations predict a new Bi-based topological insulator, and also shed light on control over spin-orbit interactions in Bi2S3 and tuning of its topological properties.

Identification of sequence polymorphisms in the displacement loop region of mitochondrial DNA as a risk factor for gastroenteropancreatic neuroendocrine neoplasm.

BACKGROUND: Gastroenteropancreatic neuroendocrine neoplasms (GEP-NEN) are relatively rare tumors that arise from the diffuse neuroendocrine system, and the biggest advances in molecular biology have helped in understanding these biological diversity of tumors over the past decades. It is important to determine the carcinogenesis of GEP-NEN from the perspective of genetic backgrounds. METHODS: Mitochondrial DNA (mtDNA) of peripheral blood from 66 GEP-NEN patients and from 75 healthy controls without history of any cancer were examined for single nucleotide polymorphisms (SNPs) and mutations in the displacement loop (D-loop) region. RESULTS: Single nucleotide polymorphisms were detected in 148 sites within the 982 bp mitochondria D-loop region from blood samples of healthy controls and GEP-NEN patients. SNPs with a rare allele frequency >5% in either controls or GEP-NEN patients were used for cancer risk analysis; a total of 23 SNPs were selected. When individual SNPs of GEP-NEN patients compared with healthy controls were analyzed, a statistically significant increase in the SNP frequency was observed for 73G, 150T, 151T, 492C, 16257A, 16261T, and 16399G in GEP-NEN patients (P<.05). It was also observed that the SNP frequency for 489C and 16519C significantly decreased in GEP-NEN patients compared with controls (P<.05). CONCLUSION: In summary, SNPs in the mutations of the mitochondrial D-loop may be valuable markers for GEP-NEN risk evaluation. Analysis of the genetic polymorphisms in the D-loop may be useful for diagnosis of high-risk individuals.

CD147 promotes cell motility via upregulation of p190-B RhoGAP in hepatocellular carcinoma.

BACKGROUND: The acquisition of inappropriate migratory feature is crucial for tumor metastasis. Rho-family GTPases including RhoA are molecular switches that play critical roles in regulating cell movement. We investigated the molecular mechanism underlying CD147 induced RhoA deactivation in hepatocellular carcinoma (HCC) cells. METHODS: Wound-healing assay was performed to study the cell motility. Analysis of RhoA activation in living cells was conducted using RhoA biosensor. Changes in the expression of certain genes were determined by quantitative real-time PCR. The expression of proteins was evaluated by Western blot. Cytoskeleton reorganization and focal adhesion formation were observed by immunofluorescence staining. Further investigation on the correlation between CD147 and p190-B RhoGAP (p190-B) in HCC tissues was performed by immunological histological chemistry analysis. RESULTS: CD147 promoted cell movement and suppressed RhoA activation. p190-B, a negative regulator of RhoA activity, was upregulated by CD147 at both mRNA and protein levels. This regulatory relationship was further confirmed by analyzing the expression pattern of CD147 and p190-B in human HCC tissues. Silencing of p190-B caused the increased formation of stress fiber and focal adhesion and blunted the impact of CD147 overexpression on cell movement, indicating that the regulatory effect of CD147 on cell movement is mediated, at least partially, by p190-B. CONCLUSIONS: These findings indicated that p190-B, a negative regulator of RhoA, is positively regulated by CD147 and contributes to the regulation of cell movement in HCC. CD147 plays critical roles in the motility of cancer cells and may be therefore a valuable drug target for anti-cancer therapy.

[Research on quality changes in ginseng stems and leaves before and after frost].

The present study is to investigate the quality changes of ginseng stems and leaves before and after frost. The contents changes of ginsenoside, free amino acid, and total phenolic compounds, as well as DPPH radical scavenging effect before and after frost were measured. The content of 9 ginsenoside monomer in ginseng stems was decreased except for Rg, and Re after frost, but in ginseng leaves was all decreased. The total content of amino acids was decreased in ginseng stems after frost, while increased in ginseng leaves. The content of phenolic compounds in ginseng stems and leaves were both decreased after frost while the ability of DPPH radical scavenging was improved. The factor of frost has great impact on the quality of ginseng stems and leaves.

Muscle Psn gene combined with exercise contribute to healthy aging of skeletal muscle and lifespan by adaptively regulating Sirt1/PGC-1α and arm pathway.

The Presenilin (Psn) gene is closely related to aging, but it is still unclear the role of Psn genes in skeletal muscle. Here, the Psn-UAS/Mhc-GAL4 system in Drosophila was used to regulate muscle Psn overexpression(MPO) and muscle Psn knockdown(MPK). Drosophila were subjected to endurance exercise from 4 weeks to 5 weeks old. The results showed that MPO and exercise significantly increased climbing speed, climbing endurance, lifespan, muscle SOD activity, Psn expression, Sirt1 expression, PGC-1α expression, and armadillo (arm) expression in aged Drosophila, and they significantly decreased muscle malondialdehyde levels. Interestingly, when the Psn gene is knockdown by 0.78 times, the PGC-1α expression and arm expression were also down-regulated, but the exercise capacity and lifespan were increased. Furthermore, exercise combined with MPO further improved the exercise capacity and lifespan. MPK combined with exercise further improves the exercise capacity and lifespan. Thus, current results confirmed that the muscle Psn gene was a vital gene that contributed to the healthy aging of skeletal muscle since whether it was overexpressed or knocked down, the aging progress of skeletal muscle structure and function was slowed down by regulating the activity homeostasis of Sirt1/PGC-1α pathway and Psn/arm pathway. Exercise enhanced the function of the Psn gene to delay skeletal muscle aging by up regulating the activity of the Sirt1/PGC-1α pathway and Psn/arm pathway.

Extracellular membrane-proximal domain of HAb18G/CD147 binds to metal ion-dependent adhesion site (MIDAS) motif of integrin ß1 to modulate malignant properties of hepatoma cells.

Several lines of evidence suggest that HAb18G/CD147 interacts with the integrin variants α3ß1 and α6ß1. However, the mechanism of the interaction remains largely unknown. In this study, mammalian protein-protein interaction trap (MAPPIT), a mammalian two-hybrid method, was used to study the CD147-integrin ß1 subunit interaction. CD147 in human hepatocellular carcinoma (HCC) cells was interfered with by small hairpin RNA. Nude mouse xenograft model and metastatic model of HCC were used to detect the role of CD147 in carcinogenesis and metastasis. We found that the extracellular membrane-proximal domain of HAb18G/CD147 (I-type domain) binds at the metal ion-dependent adhesion site in the ßA domain of the integrin ß1 subunit, and Asp(179) in the I-type domain of HAb18G/CD147 plays an important role in the interaction. The levels of the proteins that act downstream of integrin, including focal adhesion kinase (FAK) and phospho-FAK, were decreased, and the cytoskeletal structures of HCC cells were rearranged bearing the HAb18G/CD147 deletion. Simultaneously, the migration and invasion capacities, secretion of matrix metalloproteinases, colony formation rate in vitro, and tumor growth and metastatic potential in vivo were decreased. These results indicate that the interaction of HAb18G/CD147 extracellular I-type domain with the integrin ß1 metal ion-dependent adhesion site motif activates the downstream FAK signaling pathway, subsequently enhancing the malignant properties of HCC cells.

TFF3 promotes clonogenic survival of colorectal cancer cells through upregulation of EP4 via activation of STAT3.

Background: While growing evidence indicates the importance of TFF3 in cancer, the molecular mechanism of its action in cancer remains largely unknown. Clonogenic survival is a key ability for tumor cells, which is interpreted as a trait of cancer cells with tumor-initiating capabilities. We investigated the effect and the underlying mechanisms of TFF3 on the clonogenic survival of colorectal cancer (CRC) cells. Methods: Expression of TFF3 in CRC tissues and matched paracancerous tissues was determined by western blotting. Colony formation assays were performed to evaluate the clonogenic survival ability of CRC cells. PTGER4 mRNA expression was detected by quantitative polymerase chain reaction. PTGER4 promoter activity was determined by luciferase reporter assay. STAT3 nuclear localization was investigated using immunofluorescence staining. Expression of TFF3 and EP4 in CRC tissues was determined by immunohistochemistry. Results: TFF3 knockout led to decreased clonogenic survival of CRC cells, while overexpression of TFF3 resulted in the opposite effect. EP4 was found to be upregulated by TFF3 at both the mRNA and protein level. Moreover, EP4 antagonist abrogated TFF3-mediated clonogenic survival of CRC cells. PGE2 and EP4 agonist could restore the effect of TFF3 knockout on the clonogenic survival of CRC cells. Furthermore, TFF3 promoted STAT3 activation and nuclear localization. Activated STAT3 bound to PTGER4 promoter, the gene encoding for EP4, and facilitated PTGER4 transcription. Conclusions: TFF3 promotes clonogenic survival of CRC cells via upregulating EP4 expression.

Dimerization is essential for HAb18G/CD147 promoting tumor invasion via MAPK pathway.

HAb18G/CD147 is a transmembrane glycoprotein of the immunoglobulin superfamily (IgSF) and is reported to be correlated with invasion and metastasis of many cancers. The crystal structure of HAb18G/CD147 ectodomain has shown that it can form homodimers in crystal. However, the functional significance of HAb18G/CD147 dimerization remains unclear. In the present study, guided by the crystal structure, we performed extensive mutational and functional studies to identify residues critical for dimerization and molecular function of HAb18G/CD147. Fourteen mutants were purified and evaluated for their ability to form dimers in solution and in living cells. Subsequent functional validation revealed that K63E and S193A mutants, which disrupted CD147 dimerization both in solution and in living cells, showed clearly dominant-negative effects on MAPK activation, MMP2 induction and invasiveness in tumor cells. Taken together, the present study provides mutational and functional evidences demonstrating for the first time the functional importance of CD147 dimerization and its direct correlation with invasion and metastasis of tumor cells.

Electrochemically reduced single-layer MoS2 nanosheets: characterization, properties, and sensing applications.

The electrochemical study of single-layer, 2D MoS2 nanosheets reveals a reduction peak in the cyclic voltammetry in NaCl aqueous solution. The electrochemically reduced MoS2 (rMoS2) shows good conductivity and fast electron transfer rate in the [Fe(CN)6]³â»/4⁻ and [Ru(NH3)6]²âº/³âº redox systems. The obtained rMoS2 can be used for glucose detection. In addition, it can selectively detect dopamine in the presence of ascorbic acid and uric acid. This novel material, rMoS2, is believed to be a good electrode material for electrochemical sensing applications.

HAb18G/CD147 promotes cell motility by regulating annexin II-activated RhoA and Rac1 signaling pathways in hepatocellular carcinoma cells.

UNLABELLED: Tumor cells can move as individual cells in two interconvertible modes: mesenchymal mode and amoeboid mode. Cytoskeleton rearrangement plays an important role in the interconversion. Previously, we reported that HAb18G/CD147 and annexin II are interacting proteins involved in cytoskeleton rearrangement, yet the role of their interaction is unclear. In this study we found that the depletion of HAb18G/CD147 produced a rounded morphology, which is associated with amoeboid movement, whereas the depletion of annexin II resulted in an elongated morphology, which is associated with mesenchymal movement. The extracellular portion of HAb18G/CD147 can interact with a phosphorylation-inactive mutant of annexin II and inhibit its phosphorylation. HAb18G/CD147 inhibits Rho signaling pathways and amoeboid movement by inhibiting annexin II phosphorylation, promotes membrane localization of WAVE2 and Rac1 activation by way of the integrin-FAK-PI3K/PIP3 signaling pathway, and promotes the formation of lamellipodia and mesenchymal movement. CONCLUSION: These results suggest that the interaction of HAb18G/CD147 with annexin II is involved in the interconversion between mesenchymal and amoeboid movement of hepatocellular carcinoma cells.