Molecular epidemiology and antimicrobial resistance patterns of carbapenem-resistant Acinetobacter baumannii isolates from patients admitted at ICUs of a teaching hospital in Zunyi, China.

Background: Carbapenem-resistant Acinetobacter baumannii (CRAB) has emerged as a predominant strain of healthcare-associated infections worldwide, particularly in intensive care units (ICUs). Therefore, it is imperative to study the molecular epidemiology of CRAB in the ICUs using multiple molecular typing methods to lay the foundation for the development of infection prevention and control strategies. This study aimed to determine the antimicrobial susceptibility profile, the molecular epidemiology and conduct homology analysis on CRAB strains isolated from ICUs. Methods: The sensitivity to various antimicrobials was determined using the minimum inhibitory concentration (MIC) method, Kirby-Bauer disk diffusion (KBDD), and E-test assays. Resistance genes were identified by polymerase chain reaction (PCR). Molecular typing was performed using multilocus sequence typing (MLST) and multiple-locus variable-number tandem repeat analysis (MLVA). Results: Among the 79 isolates collected, they exhibited high resistance to various antimicrobials but showed low resistance to levofloxacin, trimethoprim-sulfamethoxazole, and tetracyclines. Notably, all isolates of A. baumannii were identified as multidrug-resistant A. baumannii (MDR-AB). The bla OXA-51-like, adeJ, and adeG genes were all detected, while the detection rates of bla OXA-23-like (97.5%), adeB (93.67%), bla ADC (93.67%), qacEΔ1-sul1 (84.81%) were higher; most of the Ambler class A and class B genes were not detected. MLST analysis on the 79 isolates identified five sequence types (STs), which belonged to group 3 clonal complexes 369. ST1145Ox was the most frequently observed ST with a count of 56 out of 79 isolates (70.89%). MLST analysis for non-sensitive tigecycline isolates, which were revealed ST1145Ox and ST1417Ox as well. By using the MLVA assay, the 79 isolates could be grouped into a total of 64 distinct MTs with eleven clusters identified in them. Minimum spanning tree analysis defined seven different MLVA complexes (MCs) labeled MC1 to MC6 along with twenty singletons. The locus MLVA-AB_2396 demonstrated the highest Simpson's diversity index value at 0.829 among all loci tested in this study while also having one of the highest variety of tandem repeat species. Conclusion: The molecular diversity and clonal affinities within the genomes of the CRAB strains were clearly evident, with the identification of ST1144Ox, ST1658Ox, and ST1646Oxqaq representing novel findings.

Aptamer-conjugated gold nanoparticles and their diagnostic and therapeutic roles in cancer.

The burden of incidence rate and mortality of cancer is increasing rapidly, and the development of precise intervention measures for cancer detection and treatment will help reduce the burden and pain of cancer. At present, the sensitivity and specificity of tumor markers such as CEA and CA-125 used clinically are low, while PET, SPECT, and other imaging diagnoses with high sensitivity possess shortcomings, including long durations to obtain formal reports and the inability to identify the molecular pathological type of cancer. Cancer surgery is limited by stage and easy to recur. Radiotherapy and chemotherapy often cause damage to normal tissues, leading to evident side effects. Aptamers can selectively and exclusively bind to biomarkers and have, therefore, gained attention as ligands to be targeted for cancer detection and treatment. Gold nanoparticles (AuNPs) are considered as promising nano carriers for cancer diagnosis and treatment due to their strong light scattering characteristics, effective biocompatibility, and easy surface modification with targeted agents. The aptamer-gold nanoparticles targeting delivery system developed herein can combine the advantages of aptamers and gold nanoparticles, and shows excellent targeting, high specificity, low immunogenicity, minor side effects, etc., which builds a bridge for cancer markers to be used in early and efficient diagnosis and precise treatment. In this review, we summarize the latest progress in the application of aptamer-modified gold nanoparticles in cancer targeted diagnosis and delivery of therapeutic agents to cancer cells and emphasize the prospects and challenges of transforming these studies into clinical applications.

Antimicrobial Resistance Patterns, Sequence Types, Virulence and Carbapenemase Genes of Carbapenem-Resistant Klebsiella pneumoniae Clinical Isolates from a Tertiary Care Teaching Hospital in Zunyi, China.

Purpose: Carbapenem-resistant Klebsiella pneumoniae (CRKP) has seriously threatened public health worldwide. This study aimed to investigate the antimicrobial resistance patterns, sequence types (STs), virulence and carbapenemase genes of CRKP isolates from patients in Zunyi, China. Methods: CRKP isolates were collected from the First People's Hospital of Zunyi between January 2018 and December 2020. Antimicrobial susceptibility was determined using a VITEK®2 analyzer and confirmed using either the broth dilution method, Kirby-Bauer method, or E-test assays. Carbapenemase production was examined using a modified carbapenem inactivation method. STs of the studied isolates were determined by multilocus sequence typing, and the presence of carbapenemase and virulence genes was examined using polymerase chain reaction assays. Results: In total, 94 CRKP isolates were collected. All studied isolates produced carbapenemase, and the most common carbapenemase gene was New Delhi metallo-ß-lactamase (NDM; 72.3%), followed by Klebsiella pneumoniae carbapenemase (KPC; 24.5%), and Verona integron-encoded metallo-ß-lactamase (VIM; 3.2%). Of the studied isolates, 74.3% exhibited multidrug-resistant (MDR) phenotype, and 25.7% were either pandrug-resistant (PDR) or extensively drug-resistant (XDR) phenotypes. The most prevalent sequence type was ST2407 (37.2%), followed by ST76 (21.3%) and ST11 (11.7%). The NDM gene was present in 97.1% of ST2407 isolates and 90.0% of ST76 isolates, whereas the KPC gene was present in 90.9% of ST11 isolates. The majority of the isolates carried wabG, uge, and fimH virulence genes, with prevalence rates of 94.7%, 92.6%, and 94.7%, respectively. Conclusion: This study describes NDM-producing ST2407 and ST76, as well as KPC-producing ST11, as the major clonal types of CRKP isolates in Zunyi, China. All CRKP isolates were resistant to multiple types of antibiotics, and the majority of isolates carried carbapenemase and virulence genes. Clonal spread of NDM-producing CRKP ST2407 and ST76, and KPC-producing CRKP ST11 should be strictly monitored.

Coexistence of Strong and Weak Topological Orders in a Quasi-One-Dimensional Material.

Topological materials have broad application prospects in quantum computing and spintronic devices. Among them, dual topological materials with low dimensionality provide an excellent platform for manipulating various topological states and generating highly conductive spin currents. However, direct observation of their topological surface states still lacks. Here, we reveal the coexistence of the strong and weak topological phases in a quasi-one-dimensional material, TaNiTe_{5}, by spin- and angle- resolved photoemission spectroscopy. The surface states protected by weak topological order forms Dirac-node arcs in the vicinity of the Fermi energy, providing the opportunity to develop spintronics devices with high carrier density that is tunable by bias voltage.

Paper-Based Fluidic Sensing Platforms for ß-Adrenergic Agonist Residue Point-of-Care Testing.

The illegal use of ß-adrenergic agonists during livestock growth poses a threat to public health; the long-term intake of this medication can cause serious physiological side effects and even death. Therefore, rapid detection methods for ß-adrenergic agonist residues on-site are required. Traditional detection methods such as liquid chromatography have limitations in terms of expensive instruments and complex operations. In contrast, paper methods are low cost, ubiquitous, and portable, which has led to them becoming the preferred detection method in recent years. Various paper-based fluidic devices have been developed to detect ß-adrenergic agonist residues, including lateral flow immunoassays (LFAs) and microfluidic paper-based analytical devices (µPADs). In this review, the application of LFAs for the detection of ß-agonists is summarized comprehensively, focusing on the latest advances in novel labeling and detection strategies. The use of µPADs as an analytical platform has attracted interest over the past decade due to their unique advantages and application for detecting ß-adrenergic agonists, which are introduced here. Vertical flow immunoassays are also discussed for their shorter assay time and stronger multiplexing capabilities compared with LFAs. Furthermore, the development direction and prospects for the commercialization of paper-based devices are considered, shedding light on the development of point-of-care testing devices for ß-adrenergic agonist residue detection.

Erratum: Activation of the PI3K/Akt/mTOR/p70S6K Pathway is Involved in S100A4-Induced Viability and Migration in Colorectal Cancer Cells: Erratum.

[This corrects the article DOI: 10.7150/ijms.8128.].

Elevated Serum Levels of Progranulin and Soluble Vascular Cell Adhesion Molecule-1 in Patients with COVID-19.

BACKGROUND: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is associated with the angiocentric inflammation and angiogenesis, yet the molecules involved in this process remain to be determined. METHODS: We did a cross-sectional study of a cohort of patients with COVID-19 in Zunyi, China between February 1 and March 30, 2020. Serum concentrations of PGRN were determined by enzyme-linked immunosorbent assay in patients with COVID-19 at hospital admission and at discharge. In parallel, the serum levels of soluble adhesion molecules, vascular cell adhesion molecule-1 (sVCAM-1), intercellular adhesion molecule-1 (sICAM-1), P-selectin (sP-selectin), and E-selectin (sE-selectin) were assayed by a human adhesion molecule multiplex kit. The association between serum PGRN levels and other laboratory test results was analyzed by Spearman correlation analysis. RESULTS: At baseline, the median serum PGRN levels in patients with COVID-19 were 94.8 ng/mL [interquartile range (IQR): 66.6-119.6 ng/mL], which was significantly elevated compared with those in healthy controls (46.3 ng/mL, IQR: 41.8-55.6 ng/mL). Moreover, the median serum sVCAM-1 levels were significantly higher in COVID-19 patients (1396.0 ng/mL, IQR: 1019.1-1774.8 ng/mL) than those in healthy controls (612.4 ng/mL, IQR: 466.4-689.3 ng/mL). However, the levels of sICAM-1, sP-selectin, and sE-selectin were not significantly elevated in patients with COVID-19 when compared to healthy controls. Further analysis showed that serum PGRN levels were significantly positively associated with sVCAM-1 (r= 0.675, P= 0.008) and inversely with sICAM-1 (r= -0.609, P= 0.021) and aspartate aminotransferase levels (r= -0.560, P= 0.037) in patients with COVID-19 at hospital admission. In COVID-19 patients, serum PGRN and sVCAM-1 levels fell significantly after successful treatment. CONCLUSION: The present study demonstrates elevated serum PGRN and sVCAM-1 levels in patients with COVID-19, which may provide clues as to the mechanisms underlying the pathogenesis of COVID-19. Further studies are warranted to evaluate the potential of PGRN and sVCAM-1 as biomarkers and investigate their role in the pathogenesis of COVID-19.

Molecular Epidemiology and Clinical Features of Enteroviruses-Associated Hand, Foot, and Mouth Disease and Herpangina Outbreak in Zunyi, China, 2019.

Background: Hand, foot and mouth disease (HFMD) and herpangina (HA), two of the most common childhood infectious diseases, are associated with enteroviruses (EVs) infection. The aim of this study was to identify the molecular epidemiology of enterovirus causing HFMD/HA in Zunyi, China, during 2019, and to describe the clinical features of the cases. Methods: We collected the information on demographic and clinical characteristics, laboratory data of laboratory-confirmed EVs associated HFMD/HA cases in Zunyi Medical University Third Affiliated Hospital between March 1 and July 31, 2019. EV types were determined by either one-step real time RT-PCR or partial VP1 gene sequencing and sequence alignment. Phylogenetic analysis of CVA6, CVA2, and CVA5 were established based on the partial VP1 gene sequences by neighbor-joining method. Differences in clinical characteristics and laboratory results of the cases were compared among patients infected with the most prevalent EV types. Results: From 1 March to 31 July 2019, 1,377 EVs associated HFMD/HA inpatients were confirmed. Of them, 4 (0.3%, 4/1,377) were EV-A71-associated cases, 84 (6.1%, 84/1,377) were CVA16-associated cases, and 1,289 (93.6%, 1,289/1,377) were non-EV-A71/CVA16-associated cases. Of the randomly selected 372 non-EV-A71/CVA16 cases, EV types have been successfully determined in 273 cases including 166 HFMD and 107 HA cases. For HFMD cases, the three most common types were CVA6 (80.7%, 134/166), CVA2 (5.4%, 9/166) and CVA5 (3.0%, 5/166); similarly, for HA cases, the three most prevalent serotypes were CVA6 (36.5%, 39/107), CVA2 (21.5%, 23/107) and CVA5 (18.7%, 20/107). Phylogenetic analysis showed that subclade D of CVA5, and subclade E of CVA6 and CVA2 were predominant in Zunyi during the outbreak in 2019. Compared with the cases caused by CVA16, the incidence of high fever and severe infection associated with CVA2, CVA5, and CVA6 was higher. Conclusions: The recent HFMD/HA outbreak in Zunyi is due to a larger incidence of CVA6, CVA2, and CVA5. Novel diagnostic reagents and vaccines against these types would be important to monitor and control EV infections.

Prevalence and clinical significance of common respiratory pathogens in the upper respiratory tract of children with community-acquired pneumonia in Zunyi, China.

PURPOSE: To estimate the prevalence of common respiratory pathogens among children with community-acquired pneumonia (CAP) in Zunyi City, Guizhou, China, and to assess whether the presence of common respiratory pathogens in patients is associated with disease severity. PATIENTS AND METHODS: This retrospective study assessed the prevalence of common respiratory viruses and bacteria in the upper respiratory tract of among infants and children aged 1 month to 5 years hospitalized with radiologically confirmed CAP between April 2017 and March 2018. Direct immunofluorescence assay and bacterial culture were used to identify viruses and bacteria in the upper airway specimens, respectively. The association between severe CAP and the presence of pathogens was determined using multivariate logistic regression models. RESULTS: Of the 685 patients enrolled, 583 cases had viral and/or bacterial pathogens detected, which included the presence of only viral pathogens, only bacterial pathogens, and mixed viral and bacterial pathogens in 34.3%, 29.7%, and 36.0% of cases, respectively. Respiratory syncytial virus (RSV) was the most common viral pathogen, with a prevalence rate of 39.9% (273/685). Haemophilus influenzae was the most commonly detected bacterial pathogen, with a prevalence rate of 15.3% (105/685). The presence of RSV (adjusted odds ratio [aOR], 1.9; 95% confidence interval [CI], 1.3-2.8) and Staphylococcus aureus (aOR, 13.7; 95% CI, 5.5-33.9) in children with CAP was associated with severe pneumonia. CONCLUSIONS: In a cohort of Zunyi infants and children hospitalized with CAP, RSV was the most common pathogen.

S100A9 promotes the proliferation and migration of cervical cancer cells by inducing epithelial­mesenchymal transition and activating the Wnt/ß­catenin pathway.

S100 calcium­binding protein A9 (S100A9), a member of the S100 protein family, is often upregulated in various cancers, including cervical cancer. Elevated S100A9 expression is thought to serve an important role in tumorigenesis; however, the exact role of S100A9 in the modulation of cervical cancer and the underlying molecular mechanism remain unknown. In the present study, we aimed to investigate the effects of S100A9 on the proliferation and migration of cervical cancer cells, as well as the molecular mechanisms underlying these effects. Our results demonstrated that endogenous expression of S100A9 in SiHa and CaSki cell lines was significantly higher than in the HeLa cell line. As expected, overexpression of S100A9 enhanced the proliferation and migration of cervical cancer cells. In addition, S100A9 overexpression induced epithelial­mesenchymal transition (EMT) as determined by reduced expression levels of the epithelial marker E­cadherin, whereas the expression levels of the mesenchymal marker vimentin were upregulated. Furthermore, it was reported that the effects of S100A9 in the modulation of cervical cancer cells were mediated through the Wnt/ß­catenin signaling pathway as ß­catenin knockdown significantly suppressed the ability of S100A9 to enhance the proliferation and migration of cervical cancer cells. Collectively, these findings suggest that S100A9 promoted the proliferation and migration of cervical cancer cell lines. Furthermore, the underlying molecular mechanisms may be partially attributed to the induction of EMT and activation of the Wnt/ß­catenin signaling pathway.

Genotype patterns and prevalence of human papilloma virus in non-vaccinated women in Zunyi, China.

OBJECTIVES: To determine the patterns and prevalence of human papilloma virus (HPV) genotypes in people who are not vaccinated with HPV vaccines in Zunyi. METHODS: We retrospectively collected all HPV testing results in 3,393 patients at the Third Affiliated Hospital in Zunyi Medical University, Zunyi, China between January 2014 and December 2016. The prevalence of HPV genotypes based on different stages of cervical lesions and age groups was analyzed. The clinical data of 347 HPV-positive inpatients were also retrospectively collected, and difference in the age at first sexual encounter, smoking, pregnancy, and abortion status were compared. Results: A total of 511 patients were infected with HPVs, with an overall positive rate of 15.1% (511/3,393). The most prevalent HPV genotypes were HPV-16 with prevalence rates of 24.9%, HPV-68 with 17.6%, HPV-52 with 16.2%, and HPV-58 with 14.3%. High prevalence of HPV-16 and HPV-68 in inpatients with pre-cancer and cancer lesions was one of the predominant findings. The coverage rates against cervical pre-cancer and cancer lesions for the 2 HPV vaccines, Cervarix was 35.4% and Gardasil 9 was 57%. Smoking and multiple pregnancy were more common in inpatients with HPV-16 and HPV-68 infection than those with other genotypes. Conclusions: Human papilloma virus-16 and HPV-68 are the 2 most prevalent and high-risk HPV genotypes in non-vaccinated women in Zunyi, which may serve as a guide for HPV management in Zunyi, China.

S100A6 promotes the proliferation and migration of cervical cancer cells via the PI3K/Akt signaling pathway.

Cervical cancer is the second most common gynecological cancer worldwide and remains one of the leading causes of cancer-associated mortality among women. S100A6 has been reported to be associated with the development of many types of cancer. The aim of the present study was to investigate the effect of S100A6 on the proliferation, apoptosis and migration of cervical cancer cells and its underlying molecular mechanisms. Quantative polymerase chain reaction (qPCR) was used to detect the basic mRNA level of S100A6 in HeLa, SiHa and CaSki cells. Western blot analysis was used to detect the protein level of S100A6, epithelial cadherin, neuronal cadherin, phosphorylated protein kinase B (p-Akt), t-Akt, p-glycogen synthase kinase 3ß (GSK3ß), t-GSK3ß and ß-catenin. Semi-qPCR was used to detect the mRNA level of Snail, Twist and Vimentin. MTT and Hoechst staining assays were used to detect the proliferation and apoptosis of cells, and wound healing and Transwell assays were used to detect the migration of cells. The results of the present study demonstrate that the levels of S100A6 were decreased in HeLa cells compared with in SiHa and CaSki cells. Overexpression of S100A6 in HeLa and CaSki cells promoted the proliferative and migratory ability, and had no significant effect on cellular apoptosis. Whereas the knockdown of S100A6 in SiHa and CaSki cells inhibited the proliferative and migratory ability, it had no significant effect on apoptosis. The overexpression of S100A6 in HeLa cells increased the levels of neuronal (N)-cadherin, vimentin, Snail and Twist. Conversely, knockdown of S100A6 in SiHa cells decreased the levels of N-cadherin, vimentin, Snail and Twist and increased the levels of epithelial (E)-cadherin. Furthermore, overexpression of S100A6 in HeLa cells activated the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway, and treatment with the PI3K inhibitor LY294002 partially repressed S100A6-enhanced proliferation and migration of cervical cancer cells. These results indicate that S100A6 facilitates the malignant potential of cervical cancer cells, particularly metastatic ability and epithelial-mesenchymal transition, which is mediated by activating the PI3K/Akt signaling pathway.

BCL6B suppresses proliferation and migration of colorectal carcinoma cells through inhibition of the PI3K/AKT signaling pathway.

B­cell CLL/lymphoma 6 member B (BCL6B), a BCL6­homologous gene, has been reported to be a tumor suppressor that is silenced in a variety of human cancers, including colorectal cancer (CRC). Although it was recently demonstrated that reduced expression of BCL6B is associated with tumor stage and lymph node metastasis in CRC, little is known on whether BCL6B contributes to CRC development, or the related underlying mechanism. The aim of the present study was to detect BCL6B expression in CRC cells, and determine the molecular mechanisms underlying the role of BCL6B in CRC development by investigating cell proliferation and migration in vitro. As a result, BCL6B expression was found to be notably repressed in CRC cells compared with normal intestinal epithelial cells by reverse transcription­polymerase chain reaction and western blot analysis. CRC cell proliferation was significantly inhibited by BCL6B upregulation, as indicated by MTT and colony­forming assays. Cell apoptosis was markedly induced, as indicated by flow cytometry, and BCL6B­transfected CRC cells exhibited decreased migration ability. Additionally, BCL6B overexpression diminished the phosphorylation level of AKT in CRC cells. These effects of BCL6B were empowered by treatment with the specific phosphoinositide 3 kinase (PI3K)/AKT inhibitor LY294002. Furthermore, overexpression of BCL6B resulted in upregulation of E­cadherin and downregulation of cyclin D1 and matrix metalloproteinase­9, which were strongly enhanced by LY294002. In conclusion, the findings of the present study demonstrated that BCL6B suppressed the proliferation and migration of CRC cells indirectly, via inhibition of PI3K.

High intensity focused ultrasound inhibits melanoma cell migration and metastasis through attenuating microRNA-21-mediated PTEN suppression.

High intensity focused ultrasound (HIFU) technology is becoming a potential noninvasive treatment for solid tumor. To explore whether HIFU can be applied to treat melanoma and its metastasis, we investigated the effect of HIFU on murine melanoma model. While there was little influence on cell survival, viability or apoptosis, HIFU exposure suppressed melanoma cell migration in vitro and metastasis in vivo. The expression of microRNA-21(miR-21) was down-regulated and PTEN expression was up-regulated in response to HIFU exposure, which was in concomitant with the reduction of AKT activity. Furthermore, ectopic miR-21 expression suppressed this effect of HIFU. These results demonstrate that HIFU exposure can inhibit AKT-mediated melanoma metastasis via miR-21 inhibition to restore PTEN expression. Therefore, targeting the miR-21/PTEN/AKT pathway might be a novel strategy of HIFU in treatment of melanoma.

S100A8 facilitates the migration of colorectal cancer cells through regulating macrophages in the inflammatory microenvironment.

Previous studies have shown that S100 calcium-binding protein A8 (S100A8) contributes to the survival and migration of colorectal cancer (CRC) cells. However, whether S100A8 participates in the progression and metastasis of CRC via the regulation of macrophages in the tumor inflammatory microenvironment remains unknown. In this study, phorbol myristate acetate (PMA) was used to induce the differentiation of THP-1 monocytes to macrophages. MTT assay, western blot analysis, immunofluorescence staining, semi-quantitative RT-PCR (semi-PCR), quantitative real-time PCR (qPCR), Gaussia luciferase activity assay and ELISA were performed to analyze the roles and molecular mechanisms of S100A8 in the modulation of macrophages. MTT assay, flow cytometric analysis, Hoechst staining, wound healing and Transwell migration assay were used to test the effect of S100A8 on the viability and migration of CRC cells co-cultured with macrophages in the inflammatory microenvironment. We found that THP-1 monocytes were induced by PMA and differentiated to macrophages. S100A8 activated the NF-κB pathway in the macrophages and promoted the expression of miR-155 and inflammatory cytokines IL-1ß and TNF-α in the inflammatory microenvironment mimicked by lipopolysaccharides (LPS). Furthermore, S100A8 contributed to augment the migration but not the viability of the CRC cells co-cultured with the macrophages in the inflammatory microenvironment. Altogether, our study demonstrated that S100A8 facilitated the migration of CRC cells in the inflammatory microenvironment, and the underlying molecular mechanisms may be partially attributed to the overexpression of miR-155, IL-1ß and TNF-α through activation of the NF-κB pathway in macrophages.

High intensity focused ultrasound enhances anti-tumor immunity by inhibiting the negative regulatory effect of miR-134 on CD86 in a murine melanoma model.

HIFU has been demonstrated to enhance anti-tumor immunity, however, the mechanism of which has not been well elucidated. Emerging evidence indicates that miRNAs play important roles in immune response. In this study, we used the B16F10 melanoma allograft mouse model to investigate the role of miRNAs in HIFU-enhanced anti-tumor immunity. We found that HIFU treatment decreased circulating B16F10 cells and pulmonary metastasis nodules while increased IFN-γ and TNF-α in the peripheral blood and cumulative mouse survival, which was associated with inhibition of miR-134 expression and activation of CD86 expression in tumor tissues. Further, we determined that miR-134 directly binds to the 3'UTR of CD86 mRNA to suppress its expression in B16F10 cells. When B16F10 cells transfected with miR-134 were co-cultured with normal splenic lymphocytes, the secretion of IFN-γ and TNF-α from lymphocytes was reduced and B16F10 cell survival was increased. HIFU exposure efficiently decreased miR-134 while increased CD86 expression in B16F10 cells in vitro. CD86 knockdown with siRNA markedly rescued the viability of HIFU-treated B16F10 cells that co-cultured with lymphocytes. Altogether, our results suggest that HIFU down-regulates miR-134 to release the inhibition of miR-134 on CD86 in melanoma cells, thereby enhancing anti-tumor immune response.

Promoter hypermethylation of let-7a-3 is relevant to its down-expression in diabetic nephropathy by targeting UHRF1.

Diabetic nephropathy (DN) is one of the most serious complications of diabetes mellitus (DM). Recent researches show that DNA methylation plays a role in DN. However, the exact mechanism is not fully understood. MicroRNAs (miRNAs) are a group of endogenous non-coding small RNAs that are involved in the regulation of the development of DN. We have previously demonstrated that let-7a was down-expressed in DN by microarray, but the mechanism is unclear. In this study, let-7a-3 was found to be the only gene with the CpG island in the promoter region among the three let-7a members (let-7a-1, let-7a-2 and let-7a-3) by bioinformatic methods. Also, the expression levels of three homologues of let-7a were tested by real-time PCR, and DNA methylation of the let-7a-3 gene in the promoter region was analyzed by quantitative methylation-specific PCR (qMSP) in 60 individuals, with 20 cases in the control (CON), DM and DN groups respectively. Additionally, the target gene of let-7a-UHRF1 was proved by bioinformatic analysis and dual-luciferase reporter assay. Results showed that let-7a-3 was down-regulated in DN patients. Moreover, qMSP data showed that the average methylation ratio of the let-7a-3 promoter in the DN group was significantly higher than that in the CON and DM groups (P<0.05). Data also showed that let-7a negatively regulated the mRNA and protein expressions of methylation-related gene-UHRF1 through UHRF1 3'UTR. And the expressions of UHRF1 and DNMT1 were increased in DN patients. Therefore, we concluded that promoter hypermethylation and down-expression of let-7a-3 may play a role in DN by targeting UHRF1.

[High-intensity focused ultrasound inhibits tumor metastasis in a melanoma-bearing mouse model].

OBJECTIVE: To investigate the effect of high-intensity focused ultrasound (HIFU) on tumor metastasis in mouse model bearing melanoma xenograft. METHODS: Mice bearing murine melanoma B16-F10 cell xenograft were randomized for sham-HIFU or HIFU exposure when the tumors grew to a maximum diameter of 7-10 mm, and the tumor size was measured every 3 days. The cumulative survival rate of the mice and tumor metastasis rate were calculated, and the circulating melanoma cells were detected using qRT-PCR. At 14 days after HIFU treatment, B16-F10 cells were retransplanted via the tail vein and the pulmonary metastatic nodules were counted. RESULTS: The median survival time of the mice was 19.00 days (95% CI 17.14-20.86 days) in the sham group and 26.00 days (95%CI 24.76-27.25 days) in HIFU group. The cumulative survival rate in the HIFU group was significantly higher than that in sham-HIFU group (P<0.01), and the tumor size was significantly smaller in HIFU group at 20, 23, and 26 days after HIFU treatment (P<0.05). Compared with the sham-HIFU group, HIFU group had significantly lower levels of MAGE-A3, MART1 and PAX3 at 7 days after HIFU (P<0.05) with still lower MAGE-A3 level at 14 days (P<0.05). HIFU group showed a significantly smaller number of pulmonary metastatic nodules following tumor cell retransplantation than in sham-HIFU group (P<0.01) with a metastasis inhibition rate of 42.4%. CONCLUSION: HIFU treatment can inhibit tumor metastasis in melanoma-bearing mice possibly by reducing tumor cell detachment from the primary tumor site and suppressing colonization of the circulating melanoma cells.

Inactivation of the phosphatidylinositol 3-kinase/Akt pathway is involved in BMP9-mediated tumor-suppressive effects in gastric cancer cells.

Bone morphogenetic proteins (BMPs) are members of the TGF-ß superfamily signaling factors. Expression of several BMPs (BMP2, BMP4, and BMP7) is correlated to poor prognosis in gastric cancer patients. The function of BMP9, the latest discovered and most powerful osteogenetic factor, in gastric cancer is relatively unclear. In this report, we investigated the expression, function and underlying molecular mechanisms of BMP9 in gastric cancer. The results show that BMP9 expression was markedly decreased in gastric cancer tissues and cell lines. Enforced BMP9 expression in the gastric cancer cell lines SGC-7901 and MNK-45 increased apoptosis and reduced viability and migration. The in vivo function of BMP9 was evaluated in a xenograft mouse model. Tumors derived from SGC-7901 cells with enforced BMP9 expression (SGC-7901/BMP9) showed significantly reduced size and weight compared to that from control cells. Enforced BMP9 expression resulted in decreased Akt activity shown as lower levels of phosphorylation at Ser473 and Thr308 in Akt. The PI3K/Akt inhibitor LY294002 potentiated BMP9's viability and migration suppression, and apoptosis induction, which was associated with reduced expression of snail and VEGF and increased expression of E-cadherin. In addition, tumors derived from SGC-7901/BMP9 showed reduced Akt activity and VEGF expression, and increased E-cadherin expression. Therefore, our studies reveal for the first time that inhibition of the PI3K-Akt pathway is involved in the tumor suppressor effects of BMP9 in gastric cancer.

Activation of the PI3K/Akt/mTOR/p70S6K pathway is involved in S100A4-induced viability and migration in colorectal cancer cells.

The S100 protein family member S100A4 regulates various cellular functions. Previous studies have shown that elevated expression of S100A4 is associated with progression and metastasis of colorectal cancer (CRC). However, little is known about whether and how S100A4 contributes to CRC development. In our present study, the elevated expression of S100A4 in CRC tissues compared to matched adjacent normal tissues was confirmed by immunohistochemistry, semi-quantitative RT-PCR and Western blot. Adenovirus-mediated S100A4 overexpression obviously enhanced viability and migration of CRC cells, which was detected by MTT assay and transwell assay, respectively. Additionally, S100A4 overexpression increased the phosphorylation levels of Akt, mTOR and p70S6K. These effects of S100A4 were abolished by treatment with either the specific PI3K/Akt inhibitor LY294002, or the specific mTOR/p70S6K inhibitor rapamycin. Furthermore, overexpression of S100A4 resulted in upregulation of VEGF and downregulation of E-cadherin, which were strongly reversed by either LY294002 or rapamycin. Altogether, our results demonstrate that activation of the PI3K/Akt/mTOR/p70S6K signaling pathway is involved in S100A4-induced viability, migration, upregulation of VEGF and downregulation of E-cadherin in CRC cells.