Microbiological Analysis and Mortality Risk Factors in Patients with Polymicrobial Bloodstream Infections.

Purpose: To study the etiological characteristics and risk factors affecting the prognosis of patients with polymicrobial bloodstream infections. Patients and Methods: Overall, 141 patients with polymicrobial bloodstream infections in Henan Provincial People's Hospital during 2021 were included. Laboratory test indexes, department of admission, sex, age, intensive care unit (ICU) admission, surgical history, and central venous catheter placement were collected. Patients were divided into surviving and deceased groups based on outcomes at discharge. Mortality risk factors were identified by univariate and multivariable analyses. Results: Seventy-two of 141 patients survived. Patients were mainly from the ICU and the Departments of Hepatobiliary Surgery and Hematology. Overall, 312 microbial strains were detected: 119 gram-positive, 152 gram-negative, and 13 anaerobic bacteria and 28 fungi. Among the gram-positive bacteria, coagulase-negative staphylococci were most frequent (44/119, 37%), followed by enterococci (35/119, 29.4%). Among coagulase-negative staphylococci, methicillin-resistant coagulase-negative staphylococci incidence was 75% (33/44). Among gram-negative bacteria, Klebsiella pneumoniae was most common (45/152, 29.6%), followed by Escherichia coli (25/152, 16.4%) and Pseudomonas aeruginosa (13/152, 8.6%). Among K. pneumoniae, the incidence of carbapenem-resistant (CR) K. pneumoniae was 45.7% (21/45). On univariate analysis, mortality risk factors included increased white blood cells and C-reactive protein, decreased total protein and albumin, CR strains, ICU admission, central venous catheter, multiple organ failure, sepsis, shock, pulmonary diseases, respiratory failure, central nervous system diseases, cardiovascular diseases, hypoproteinemia, and electrolyte disturbances (P < 0.05). Multivariable analysis showed that ICU admission, shock, electrolyte disorders, and central nervous system diseases were independent mortality risk factors. The survival curve shows that the survival rate of patients with polymicrobial CR bloodstream infections was lower than that of patients with polymicrobial non-CR bloodstream infections (P=0.029). Conclusion: Patients with polymicrobial bloodstream infections are typically critically ill and harbor multidrug-resistant bacteria. Thus, to minimize mortality rate in critically ill patients, changes in infectious flora should be monitored, antibiotics selected reasonably, and invasive procedures reduced.

Characteristics of humoral and cellular responses to coronavirus disease 2019 (COVID-19) inactivated vaccine in central China: A prospective, multicenter, longitudinal study.

Introduction: In China, the long-term immunogenicity and adverse effects of inactivated vaccines produced by different or the same manufacturer remain unclear. Therefore, the objective of this study was to evaluate the cellular immune responses and neutralizing antibody kinetics of homologous and heterologous administrations of an inactivated coronavirus disease 2019 (COVID-19) vaccine 240 days after the second vaccination. Methods: This prospective, multicenter, observational, longitudinal study involved 595 participants with a negative SARS-CoV-2 polymerase chain reaction result who were serologically tested and followed for 8 months after vaccination. Neutralizing antibodies, interferon-gamma (IFN-γ), interleukin (IL)-6, CD4+ T-lymphocyte, and B-lymphocyte counts were evaluated in serum samples after stimulation with 2 µg/mL SARS-CoV-2 spike protein for 16 h at follow-up intervals of 2 months. Results: Most participants [582/595; 146 male participants, 449 female participants; mean age 35 (26-50 years)] rapidly developed neutralizing antibodies after two doses of the vaccine administered 3-weeks apart. The positive rate of neutralizing antibodies peaked at 97.7% at 60-90 days, decreased, and stabilized at 82.9% at 181-240 days post-vaccination. Lower antibody concentrations were correlated with older age, longer duration after vaccination, non-health care workers, mixed-manufacturer vaccinations, and intervals of less than 40 days between two doses of vaccination, whereas lower IFN-γ levels and B-lymphocyte counts were associated with older age, blood type A, and non-health care workers. A higher IL-6 level was associated with older age, mixed-manufacturer vaccinations, intervals of less than 40 days between two doses of vaccination, and medical staff. Adverse reactions were mild or moderate and self-limited, with no serious events reported. Discussion: Two doses of the Chinese inactivated vaccine induced robust and rapid antibody expression and cellular immune responses. Boosting vaccination is considered important, as antibodies and cellular immune responses were reduced in susceptible populations.

Evaluation of Commercial Products for Colistin and Polymyxin B Susceptibility Testing for mcr-Positive and Negative Escherichia coli and Klebsiella pneumoniae in China.

Purpose: To evaluate the performance of five widespread commercial products for colistin and polymyxin B susceptibility testing in China for mcr-positive and -negative Escherichia coli and Klebsiella pneumoniae. Methods: A total of 132 E. coli and 83 K. pneumoniae strains (including 68 mcr-1-positive E. coli and 28 mcr-8-positive K. pneumoniae) were collected. We analysed the performance of colistin susceptibility (with Vitek 2 and Phoenix M50) and the performance of polymyxin B susceptibility (with DL-96II, MA120, and a Polymyxin B Susceptibility Test strip; POL E-strip). Broth microdilution was used as the gold standard. Categorical agreement (CA), essential agreement (EA), major error (ME), and very major error (VME) were calculated for comparisons. Results: For E. coli, the total CA, EA, ME, and VME to colistin were as follows: Vitek 2, 98.5%/98.5%/0%/2.9%; and Phoenix M50, 98.5%/97.7%/0%/2.9%. The total CA, EA, ME, and VME to polymyxin B were as follows: POL E-strip, 99.2%/63.6%/1.6%/0%; MA120, 70.0%/-/0%/58.8%; and DL-96II, 80.2%/-/1.6%/36.8%. Only Vitek 2 and Phoenix M50 presented satisfactory performances for mcr-1-positive E. coli. For K. pneumoniae, the total CA, EA, ME, and VME to colistin were as follows: Vitek 2, 73.2%/72.0%/0%/61.6%; and Phoenix M50, 74.7%/74.7%/0%/58.3%. The total CA, EA, ME, and VME to polymyxin B were as follows: POL E-strip, 91.6%/74.7%/2.1%/16.7%; MA120, 92.8%/-/2.1%/13.9%; and DL-96II, 92.2%/-/2.1%/8.3%. All systems were unsatisfactory for mcr-8-positive K. pneumoniae. When the susceptibility of mcr-negative strains was tested, all systems presented excellent performance. Conclusion: Vitek 2 and Phoenix M50 with colistin for E. coli showed acceptable performance regardless of mcr-1 expression, while DL-96II, MA120, and the POL E-strip performed worse for mcr-1-positive strains. Furthermore, mcr-8 greatly affected the performance of all systems with both colistin and polymyxin B for K. pneumoniae isolates.

Validation of a predictive model for coronary artery disease in patients with diabetes.

BACKGROUND: No reliable model can currently be used for predicting coronary artery disease (CAD) occurrence in patients with diabetes. We developed and validated a model predicting the occurrence of CAD in these patients. METHODS: We retrospectively enrolled patients with diabetes at Henan Provincial People's Hospital between 1 January 2020 and 10 June 2020, and collected data including demographics, physical examination results, laboratory test results, and diagnostic information from their medical records. The training set included patients ( n  = 1152) enrolled before 15 May 2020, and the validation set included the remaining patients ( n  = 238). Univariate and multivariate logistic regression analyses were performed in the training set to develop a predictive model, which were visualized using a nomogram. The model's performance was assessed by area under the receiver-operating characteristic curve (AUC) and Brier scores for both data sets. RESULTS: Sex, diabetes duration, low-density lipoprotein, creatinine, high-density lipoprotein, hypertension, and heart rate were CAD predictors in diabetes patients. The model's AUC and Brier score were 0.753 [95% confidence interval (CI) 0.727-0.778] and 0.152, respectively, and 0.738 (95% CI 0.678-0.793) and 0.172, respectively, in the training and validation sets, respectively. CONCLUSIONS: Our model demonstrated favourable performance; thus, it can effectively predict CAD occurrence in diabetes patients.

TGIF1 overexpression promotes glioma progression and worsens patient prognosis.

Transforming growth factor ß-induced factor homeobox 1 (TGIF1) reportedly promotes the pathological processes of various malignant tumors. However, few studies have investigated the role of TGIF1 in gliomas. We aimed to explore the relationship between TGIF1 expression and the clinical characteristics of patients with glioma, including their overall survival. A total of thousands transcriptome datapoints were downloaded from public databases to determine the correlations between TGIF1 and various clinicopathological features using the Wilcoxon or Kruskal-Wallis tests. The Kaplan-Meier and Cox statistical methods were used to explore the prognostic significance of TGIF1. Gene set enrichment analysis (GSEA) was used to indirectly identify the pathological mechanisms modulated by TGIF1, and compounds that inhibit its expression were determined using a connectivity map (CMap). TGIF1 was significantly overexpressed in gliomas and was correlated with unfavorable prognostic factors and shorter overall survival. Cox analysis confirmed that TGIF1 expression was a significant predictor of poor prognosis in patients with glioma. GSEA revealed that the signaling pathways associated with TGIF1 expression in glioma included extracellular matrix receptor- and cell cycle-modulating proteins. CMap analysis showed that the small molecules scriptaid, torasemide, dexpropranolol, ipratropium bromide, and harmine were potential negative regulators of TGIF1. Finally, in vitro experiments demonstrated that knockdown of TGIF1 significantly inhibited the proliferation and invasion of glioma cell. Taken together, our study, which is the first to comprehensively analyze TGIF1 in gliomas, revealed it to be a novel oncogene in terms of its association with this disease. As such, TGIF1 may be a potential therapeutic target for individualized treatment of patients with glioma.

CLSPN is a potential biomarker associated with poor prognosis in low-grade gliomas based on a multi-database analysis.

BACKGROUND: The oncogene CLSPN, also known as claspin, has regulatory effects in a variety of tumours; however, it is not clear whether CLSPN is a therapeutic target in low-grade gliomas (LGG). In this study, the prognostic value of CLSPN in LGG and its role as an immunotherapeutic target were evaluated. METHODS: Transcriptome and methylation data for thousands of patients with glioma were collected from various databases, including The Cancer Genome Atlas, Chinese Glioma Genome Atlas, and Gene Expression Omnibus. Subsequently, a series of bioinformatics methods were used to evaluate the relationships between CLSPN and prognosis, clinical features, methylation status, immune cells, and molecular signaling pathways in LGG. RESULTS: CLSPN expression levels were positively correlated with major malignant characteristics of LGG, and low expression of CLSPN was associated with a better prognosis. The methylation sites cg04263115 and cg06100291 negatively regulated the expression of CLSPN, and increased methylation levels at these sites were related to a longer survival time in patients with LGG. CLSPN was positively correlated with tumour-infiltrating immune cells and showed high copy number variation in these cells. There was a positive regulatory relationship between CLSPN expression and programmed death-1 (PD-1) and programmed cell death ligand 1 (PD-L1). A gene set enrichment analysis revealed that CLSPN activates a variety of cancer signaling pathways. CONCLUSION: CLSPN was identified as an independent risk factor for LGG with excellent prognostic value.

Early predictors of severe COVID-19 among hospitalized patients.

BACKGROUND: Limited research has been conducted on early laboratory biomarkers to identify patients with severe coronavirus disease (COVID-19). This study fills this gap to ensure appropriate treatment delivery and optimal resource utilization. METHODS: In this retrospective, multicentre, cohort study, 52 and 64 participants with severe and mild cases of COVID-19, respectively, were enrolled during January-March 2020. Least absolute shrinkage and selection operator and binary forward stepwise logistic regression were used to construct a predictive risk score. A prediction model was then developed and verified using data from four hospitals. RESULTS: Of the 50 variables assessed, eight were independent predictors of COVID-19 and used to calculate risk scores for severe COVID-19: age (odds ratio (OR = 14.01, 95% confidence interval (CI) 2.1-22.7), number of comorbidities (OR = 7.8, 95% CI 1.4-15.5), abnormal bilateral chest computed tomography images (OR = 8.5, 95% CI 4.5-10), neutrophil count (OR = 10.1, 95% CI 1.88-21.1), lactate dehydrogenase (OR = 4.6, 95% CI 1.2-19.2), C-reactive protein OR = 16.7, 95% CI 2.9-18.9), haemoglobin (OR = 16.8, 95% CI 2.4-19.1) and D-dimer levels (OR = 5.2, 95% CI 1.2-23.1). The model was effective, with an area under the receiver-operating characteristic curve of 0.944 (95% CI 0.89-0.99, p < 0.001) in the derived cohort and 0.8152 (95% CI 0.803-0.97; p < 0.001) in the validation cohort. CONCLUSION: Predictors based on the characteristics of patients with COVID-19 at hospital admission may help predict the risk of subsequent critical illness.

Prevalence and Genetic Diversity of Clostridium perfringens Isolates in Hospitalized Diarrheal Patients from Central China.

OBJECTIVE: This study aimed to investigate the prevalence, genetic diversity and clinical characteristics of Clostridium perfringens isolates from hospitalized clinical diarrheal patients. METHODS: A prospective study was conducted on 1108 patients with diarrhea during hospitalization. Stool samples were cultured for C. perfringens, and the toxin genes were detected by PCR. The available clinical data of 112 patients were analyzed to study the clinical features of various isolates. Multi-locus sequence typing (MLST) was performed to assess phylogenetic relationship between different isolates. RESULTS: A total of 153 (13.8%) isolates were obtained from patients' stools. C. perfringens type F (49.0%) was the major toxin type in the isolates, followed by type A (n = 59, 38.6%) and type C (n = 14, 9.2%). Patients older than 50 years and those with underlying diseases of cancer, hepatobiliary system, and ulcerative colitis (UC) were more predisposed to C. perfringens type F and type A infection than to type C. The patients infected with type C experienced more severe clinical symptoms compared to those with type A infection. There was a significant association between type FC and foodborne gastrointestinal (GI) diseases (p = 0.018), between type FP and antibiotic-associated diarrhea (AAD) (p < 0.001), and between type A and sporadic diarrhea (SD) (p < 0.001). Phylogenetic analysis indicated that type F isolates carrying a chromosomal cpe gene mainly belonged to ST77 (6/15 isolates). Type F isolates with cpe gene on a plasmid exhibited high genetic diversity. CONCLUSION: High prevalence and considerable genetic diversity of C. perfringens type F were found in clinical diarrheal patients. Elderly people and patients with cancer, hepatobiliary diseases or UC, or suspected of having food poisoning (FP) may be targeted for routine testing of C. perfringens toxin genes and may benefit from early detection of C. perfringens type C isolates that cause more severe clinical symptoms.

Non-tuberculous Mycobacterial Infection of the Musculoskeletal System Detected at Two Tertiary Medical Centres in Henan, China, 2016-2020.

Non-tuberculous mycobacterial (NTM) infection of the musculoskeletal system is rare but poses a grave threat to public health. These infections yield non-specific symptoms that remain undetected until the development of the later stages of the disease. In this study, we performed a retrospective review of 25 cases of musculoskeletal NTM infection at two tertiary medical centres over a 5-year period to determine the clinical features and improve the current clinical diagnosis and treatment. The most common mycobacterial species detected were Mycobacterium fortuitum in eleven patients, Mycobacterium abscessus in eight patients, Mycobacterium houstonense in three patients, Mycobacterium avium in two patients, and Mycobacterium smegmatis in one patient. The sites of infection included the limbs and joints, most commonly the knee (ten patients) and foot (six patients). The median duration from the onset of symptoms to diagnosis was 2.5 months (0.8-13.5 months). Deep sinus tracts extending to the surgical site were observed in 60% of the patients (15/25), and granulomatous inflammation and granulomatous inflammation with necrosis occurred in 60% of the patients (15/25). All patients underwent surgical treatment for infection control, and all patients, except one, received antimycobacterial therapy based on drug sensitivity assays. The median duration of the antimicrobial chemotherapy was 5 months (range: 3-20 months). At the final follow-up, 24 patients presented with absence of recurrence and one patient succumbed owing to heart failure after debridement. Our findings highlight the importance of vigilance and improvements in the diagnostic methods for musculoskeletal NTM infection. Aggressive surgical treatment and antimycobacterial drug treatment can help achieve satisfactory results.

Evaluation of an optimized method to directly identify bacteria from positive blood cultures using MALDI-TOF mass spectrometry.

BACKGROUND: Although various methods have been developed to directly identify bacteria from positive blood cultures by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), the necessity of using commercial kits still leads to a high cost and long assay time. Moreover, few evaluations of these methods have been conducted. This study aimed to evaluate the feasibility of an optimized MALDI-TOF MS method for direct identification of bacteria in positive blood cultures. METHODS: A total of 829 non-repeated positive cultures were collected from July 2018 to August 2019, and direct identification was performed by an optimized MALDI-TOF MS method. The same positive blood cultures were sub-cultivated to obtain a single bacterial colony and identified by classical biochemical BD testing, which is the gold standard to compare the accuracy of direct identification of positive blood cultures by MALDI-TOF MS. RESULTS: After excluding 7 false-positive samples from the 829 positive blood cultures, the most accurate rate of direct identification by this optimized MALDI-TOF MS method was for gram-negative bacteria (91.5%), followed by gram-positive bacteria (88.3%), fungi (84.8%), anaerobic bacteria (80%), and other rare bacteria (66.67%). CONCLUSION: Common bacteria in positive blood cultures can be identified directly within 1 hour by MALDI-TOF MS, and thus, this optimized method can be used as a primary identification method by clinicians. Routine implementation of this method may significantly increase the optimal utilization rate of antibiotics and decrease mortality in bacteremia patients.

The first imported case of melioidosis in a patient in central China.

Here, we report the first imported case of melioidosis from Laos in central China. COMPACT VITEK2 identification system and PCR, as well as sequencing methods confirmed that the patient was infected by Burkholderia pseudomallei, a bacterial species closely related to an isolate detected in Thailand. These findings are highly valuable for an early diagnosis, treatment and to prevent the spread of this emerging infectious disease in central China.

Role of p62/SQSTM1 in lipopolysaccharide (LPS)-induced mucus hypersecretion in bronchial epithelial cells.

AIMS: The aims of this study were to evaluate the effects of p62/SQSTM1 expression levels on lipopolysaccharide (LPS)-induced mucus secretion in BEAS-2B bronchial epithelial cells by measuring expression levels of the MUC5AC gene and the Mucin-5AC (MUC5AC) protein. MATERIALS AND METHODS: Bronchial epithelial cells, BEAS-2B, were treated with LPS at different time points. Rapamycin, an autophagy agonist, was added to the BEAS-2B cells 30 min before LPS treatment. Lentivirus transfection was then used to knock down the expression of p62/SQSTM1 (Sequestosome 1) to investigate changes in the downstream signaling pathway. Western blotting and immunofluorescence were used to study the expression levels of MUC5AC, and reverse transcription-polymerase chain reaction (RT-PCR) was used to study the expression of MUC5AC mRNA. KEY FINDINGS: LPS treatment of BEAS-2B cells inhibited autophagy, activated the nuclear factor kappa B (NF-κB) signaling pathway and increased the expression of MUC5AC. The autophagy agonist, rapamycin, activated autophagy, inhibited the NF-κB signaling pathway and decreased LPS-induced expression of MUC5AC. Knockdown of p62/SQSTM1 expression reduced activation of the NF-κB signaling pathway and reduced LPS-induced mucus secretion by BEAS-2B cells in vitro. SIGNIFICANCE: In this in vitro study, which utilized BEAS-2B bronchial epithelial cells, p62/SQSTM1 was shown to have a role in LPS-induced mucus hypersecretion by activating the NF-κB signaling pathway.

Critical role of MAVS in the protection against Clostridium difficile-induced colitis.

Clostridium difficile (C. difficile) is an opportunistic bacteria that flourishes in intestinal flora is altered by antibiotic use and can cause large intestinal colitis if left untreated. The mechanism of MAVS-mediated innate immune signaling in response to C. difficile infection remains unclear. This knowledge gap was addressed in the present research by administration of an antibiotic cocktail to WT and MAVS-deficient (MAVS-/-) mice for five days, followed by the oral administration of C. difficile VPI 10,463 strain (1 × 107 colony forming units). Subjects were subsequently observed for another eight days for signs of colitis. Colon and cecum tissue samples were harvested from naive and infected mice two days post-infection for histopathologic analysis. Colon tissue samples were harvested to analyze cytokine gene expression and RegIIIß/γ gene expression. MAVS-deficient mice suffered significantly higher mortality rates as well as increased mucosal tissue inflammation and damage after C. difficile infection (P <0.05). MAVS-/- mice displayed a significantly greater increase in IL-6, IL-1ß, TNF-α and IFN-ß expression in colon tissues in contrast to WT mice challenged with C. difficile (P <0.05). RegIIIß/γ gene expression was severely attenuated in the colons of MAVS-/- mice (P <0.05). These findings underscore MAVS as a vital innate immune system mediator in the intestinal mucosa and further suggests that MAVS-mediated maintenance of the intestinal epithelial barrier is an important defense against enteric pathogens.

The characteristics of Clostridium difficile ST81, a new PCR ribotype of toxin A- B+ strain with high-level fluoroquinolones resistance and higher sporulation ability than ST37/PCR ribotype 017.

Antibiotic exposure, Clostridium difficile toxins, and spore formation are key factors involved in the pathogenesis of Clostridium difficile infection (CDI). A high incidence of CDI due to toxin A- B+ strains, which were classified into two genotypes (ST81 and ST37) by multilocus sequence typing, was identified in Beijing Friendship Hospital in 2016-2017. ST81 was the most prevalent type, accounting for 81.25% of toxin A- B+ strains. ST81 corresponded to a novel PCR ribotype, PKI-017, with one less band than ST37/ribotype 017 in PCR ribotyping. All ST81 strains showed a high level of ciprofloxacin resistance (MICs ≥ 64 µg mL-1) and moxifloxacin resistance (MICs ≥ 128 µg mL-1) with the amino acid substitutions Thr82 to Ile in GyrA and Ser416 to Ala in GyrB. There was either no mutation or only the single amino acid mutation Thr82 to Ile in the GyrA subunit of ST37/ribotype 017 strains, which had lower MICs of ciprofloxacin (4-64 µg mL-1) and moxifloxacin (4-16 µg mL-1). In addition, ST81 strains exhibited higher spore formation ability than ST37/ribotype 017 strains. Overall, our results indicated that ST81 strains had unique characteristics distinguishable from ST37 strains and emphasized the importance of ongoing surveillance for this new genotype.

Molecular epidemiology and antimicrobial susceptibility of human Clostridium difficile isolates from a single institution in Northern China.

Because the epidemiology of Clostridium difficile infection (CDI) is region-specific, the present study was undertaken to examine the epidemiology of C difficile outbreaks in Beijing, China.Eighty nonduplicate isolates were collected from March, 2016 to December, 2016. The molecular type and phylogenetic analysis were evaluated by multilocus sequence typing (MLST). The minimum inhibitory concentrations (MICs) for 11 antibiotics and the resistance mechanisms were investigated.Sixty-five toxigenic strains (81.25%), including 22 tcdABCDT strains (27.5%) and 43 tcdABCDT strains (53.75%), and also 15 nontoxigenic strains (tcdABCDT; 18.75%) were detected. MLST identified 21 different sequence types (STs), including 2 novel types (ST409 and ST416). All isolates were susceptible to metronidazole, vancomycin, fidaxomicin, piperacillin/tazobactam, and meropenem, and all were effectively inhibited by emodin (MICs 4-8 µg/mL). The resistance rates to rifaximin, ceftriaxone, clindamycin, erythromycin, and ciprofloxacin were 8.75%, 51.25%, 96.25%, 81.25%, and 96.25%, respectively; 81.25% (65/80) of isolates were multidrug-resistant. Amino acid mutations in GyrA and/or GyrB conferred quinolone resistance. One novel amino acid substitution, F86Y in GyrA, was found in 1 CIP-intermediate strain. The erm(B) gene played a key role in mediating macrolide-lincosamide-streptogramin B (MLSB) resistance. Erm(G) was also found in erm(B)-negative strains that were resistant to both erythromycin and clindamycin. RpoB mutations were associated with rifampin resistance, and 2 new amino mutations were identified in 1 intermediate strain (E573A and E603N).Regional diversity and gene heterogeneity exist in both the ST type and resistant patterns of clinical C difficile isolates in Northern China.

Inhibitory Effect of Vaginal Lactobacillus Supernatants on Cervical Cancer Cells.

Lactobacilli have been shown to inhibit the proliferation of several types of cancer cells, but the effects of vaginal Lactobacilli on cervical cancer cells have seldom been reported. We incubated Caski cells with supernatants of predominant strains in the vagina and investigated their effects on cell growth and the possible mechanisms. Cell-free supernatants of Lactobacillus crispatus, L. jensenii, and L. gasseri were prepared and purified. Caski cells were treated with various concentrations of Lactobacillus supernatants (LS). The effect of LS on cell growth was investigated using MTT assays. The influence of LS on the cell cycle and expression of human papillomavirus (HPV) E6 and E7 oncogenes was determined by flow cytometry and RT-PCR, respectively. LS-inhibited Caski cell proliferation caused morphological changes in a pH-independent manner. Flow cytometric analysis revealed that cells exposed to LS exhibited a significant increase of cell number in S phase and a strong decrease of cell number in G2/M phase. Expression of HPV E6 and E7 oncogenes, as well as CDK2 and cyclin A was decreased after treatment with LS, while expression of p21 was increased. Supernatants of L. crispatus, L. jensenii, and L. gasseri have inhibitory effects on the viability of cervical cancer cells via regulation of HPV oncogenes and cell cycle-related genes. Lactobacillus, as a promising treatment for cancer, is being assessed for its effect, and these results provide further evidence in this respect.

MicroRNA-127 is downregulated by Tudor-SN protein and contributes to metastasis and proliferation in breast cancer cell line MDA-MB-231.

Tudor-SN is a multifunctional protein that is highly expressed in multiple cancers including breast cancer. Tudor-SN, as a component in RNA-induced splicing complex, was recently reported to regulate gene expression in a microRNA (miRNA)-dependent manner, such as let-7, miR-34a and miR-221. However, how Tudor-SN is associated with cancer development still remains largely elusive. In the present study, we explored the role of Tudor-SN in breast cancer. Stable knockdown of endogenous Tudor-SN, performed on the breast cancer cell line MDA-MB-231 by small hairpin RNA expression vectors, suppressed the in vitro migration and invasion ability of the metastatic breast cancer cell line. Interestingly, we found Tudor-SN as a miRNA regulator according to microarray analysis, and further identified that Tudor-SN negatively regulated the expression of miR-127, and consequently increased the expression of the proto-oncogene BCL6 which was a convincing target of miR-127. Moreover, overexpression of miR-127 reduced the in vitro migration and proliferation ability of breast cancer cell MDA-MB-231. Collectively, our results suggested a novel mechanism that Tudor-SN promoted metastasis and proliferation of breast cancer cells via downregulating the miR-127 expression.

Identification of p100 target promoters by chromatin immunoprecipitation-guided ligation and selection (ChIP-GLAS).

The multifunctional protein p100 is a vital transcriptional regulator that increases gene transcription by forming a physical bridge between promoter-specific transcription factors and the basal transcription machinery. To identify potential signal transduction pathways in which human p100 acts as a coregulator and to find target promoter regions that may interact with p100, we performed a promoter microarray assay called chromatin immunoprecipitation-guided ligation and selection (ChIP-GLAS). From this assay, we determined that a set of promoter fragments, including several factors in the transforming growth factor beta (TGF-ß) signaling pathway, exhibited interaction with p100. The ChIP-GLAS data were validated by RT-PCR assessing the mRNA expression of various factors in the TGF-ß signaling pathway in cell lines.