The FnBPA from methicillin-resistant Staphylococcus aureus promoted development of oral squamous cell carcinoma.

Background: Oral squamous cell carcinoma (OSCC) is the most common tumor in the oral cavity. Methicillin-resistant Staphylococcus aureus (MRSA) were highly detected in OSCC patients; however, the interactions and mechanisms between drug-resistant bacteria (MRSA) and OSCC are not clear. Aim: The aim of this study was to investigate the promotion of MRSA on the development of OSCC. Methods: MRSA and MSSA (methicillin-susceptible) strains were employed to investigate the effect on the proliferation of OSCC in vitro and vivo. Results: All of the MRSA strains significantly increased the proliferation of OSCC cells and MRSA arrested the cell cycles of OSCC cells in the S phase. MRSA activated the expression of TLR-4, NF-κB and c-fos in OSCC cells. MRSA also promoted the development of squamous cell carcinoma in vivo. The virulence factor fnbpA gene was significantly upregulated in all MRSA strains. By neutralizing FnBPA, the promotions of MRSA on OSCC cell proliferation and development of squamous cell carcinoma were significantly decreased. Meanwhile, the activation of c-fos and NF-κB by MRSA was also significantly decreased by FnBPA antibody. Conclusion: MRSA promoted development of OSCC, and the FnBPA protein was the critical virulence factor. Targeting virulence factors is a new method to block the interaction between a drug-resistant pathogen and development of tumors.

Antibiotic-induced dysbiosis of the rat oral and gut microbiota and resistance to Salmonella.

OBJECTIVES: Antibiotics play a great role in the treatment of infectious diseases, but meantime, they cause great disturbances to host microbiota. Studies on different antibiotic-induced changes in host microbiota are relatively scarce. This study aimed to investigate the changes in oral and gut microbiota and possible alterations of gut resistance to Salmonella induced by the administration of antibiotics. METHODS: The experiment was conducted by administering antibiotics to rats and detecting oral and gut microbiota by 16S rRNA gene sequencing. In second part, after treating with antibiotics or Lactobacillus rhamnosus the rats were infected by Salmonella Typhimurium and the pathogen burden in the gut was counted by colony forming unit assay. RESULTS: The gut microbiota underwent dramatic changes after both vancomycin and ampicillin treatment. The alpha diversity sharply decreased, and the microbiota composition showed a significant difference. However, the gut microbiota recovered within four weeks after stopping antibiotics administration, although this recovery was incomplete. Oral microbiota did not show significant alterations in both alpha and beta diversities. The number of pathogens in the gut in the control group was significantly lower than that in the antibiotic-treated group but only lasted for the first 4 days after infection. CONCLUSIONS: Antibiotics cause dramatic alterations in the number and diversity of gut microbiota but not oral microbiota. These changes in the gut microbiota could incompletely recover four weeks later. When infected with pathogens after antibiotic administration, the rats show a decrease in colonization resistance in the gut for the first four days after infection.

Eleven years of experience reveals that fine-needle aspiration cytology is still a useful method for preoperative diagnosis of breast carcinoma.

Fine needle aspiration cytology (FNAC) has been used extensively for the diagnosis of breast lesions over the past 15 years. More recently, large gauge needle biopsy such as core biopsy has been used and the clinical value of FNAC has therefore been questioned. To answer this clinical question, we performed an 11-year study in which 1238 aspirates from patients with a breast lump were involved. In total, 1071 breast carcinomas were diagnosed with postoperative histological diagnosis. One thousand and forty-six of these 1071 breast carcinomas were definitely diagnosed by FNAC. Only one breast carcinoma identified by FNAC was not finally verified by histological diagnosis postoperatively. The diagnostic sensitivity, diagnostic specificity, overall accuracy, and the pseudo-negative and pseudo-positive results of FNAC for diagnosing breast carcinoma are 97.72%, 99.4%, 97.94%, 2.28%, and 0.6%, respectively. The method is rapid, accurate, and essentially complication-free, particularly in patients for neoadjuvant chemotherapy or endocrine therapy. The results suggest that FNAC is still a useful and reliable method for the preoperative diagnosis of breast carcinoma.