Clinical Performance of the Xpert® CT/NG Test for Detection of Chlamydia trachomatis and Neisseria gonorrhoeae: A Multicenter Evaluation in Chinese Urban Hospitals.

Background: We aimed to evaluate the clinical performance of the GeneXpert® (Xpert) CT/NG assay for the detection of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) using urine and cervical swabs collected from patients in China. Methods: This study was conducted from September 2016 to September 2018 in three Chinese urban hospitals. The results from the Xpert CT/NG test were compared to those from the Roche cobas® 4800 CT/NG test. Discordant results were confirmed by DNA sequence analysis. Results: In this study, 619 first void urine (FVU) specimens and 1,042 cervical swab specimens were included in the final dataset. There were no statistical differences between the results of the two tests for the detection of CT/NG in urine samples (p > 0.05), while a statistical difference was found in cervical swabs (p < 0.05). For CT detection, the sensitivity and specificity of the Xpert test were 100.0% (95%CI = 96.8-99.9) and 98.3% (95%CI = 96.6-99.2) for urine samples and 99.4% (95%CI = 96.5-100.0) and 98.6% (95%CI 97.5-99.2) for cervical swabs, respectively. For NG detection, the sensitivity and specificity of the Xpert test were 99.2% (95%CI = 94.9-100.0) and 100.0% (95%CI = 99.0-100.0) for urine and 100% (95%CI = 92.8-100.0) and 99.7% (95%CI = 99.0-99.9) for cervical swabs, respectively. Conclusion: The Xpert CT/NG test exhibited high sensitivity and specificity in the detection of CT and NG in both urine and cervical samples when compared to the reference results. The 90-min turnaround time for CT and NG detection at the point of care using Xpert may enable patients to receive treatment promptly.

Human CD133-positive hematopoietic progenitor cells initiate growth and metastasis of colorectal cancer cells.

The tumour-specific 'pre-metastatic niche' has emerged as a potential driving force for tumour metastasis and has been confirmed using mouse models of cancer metastasis. Vascular endothelial growth factor receptor-1(+) hematopoietic progenitor cells (HPCs) have been shown to play an important role in metastasis, forming a 'pre-metastatic niche' at designated sites for distant tumour progression. Here, CD133+ human umbilical hematopoietic progenitor cells (HUHPCs) were purified from human umbilical cord blood and expanded in vitro. We studied the effects of CD133+ HUHPCs on the growth and metastasis of four colorectal cancer (CRC) cell lines by using cell-to-cell co-culture. Our results revealed that CD133+ HUHPCs promoted the proliferation and invasion of CRC cells in vitro and enhanced tumour growth and metastasis in vivo. Moreover, CD133+ HUHPCs were observed in the pre-metastatic liver tissue using immunohistochemical analysis after co-injection of SW480/EGFP(+) cells and HUHPCs. Further experiments were therefore conducted to uncover the molecular mechanisms by which CD133+ HUHPCs influenced colon carcinogenesis and cancer progression. Extracted proteins were separated using the two-dimensional difference in gel electrophoresis technology. Among the differentially expressed proteins, mitogen-activated protein 4 kinase 4, stromal cell-derived factor-1, matrix metallopeptidase 9, calumenin, peripherin, leucine zipper, putative tumour suppressor 1 and guanidinoacetate methyltransferase attracted our attention. Western blot analysis further confirmed the differential expression of these proteins. Altogether, these results suggest that CD133+ HUHPCs may induce proliferation or metastasis of CRC cells and impact their derived proteins by providing a pre-metastatic microenvironment.

[Relationship between MAP3K5 and Epstein-Barr virus-encoded miR-BART22 expression in nasopharyngeal carcinoma].

OBJECTIVE: To detect the expression of MAP3K5 and miR-BART22 encoded by Epstein-Barr virus and explore their relationship in nasopharyngeal carcinomas (NPCs). METHODS: Fifty-three archived specimens of NPCs and 30 nasopharyngitis specimens were collected for detecting the expression of EBERs and miR-BART22 by in situ hybridization, and the expression of MAP3K5 was detected using immunohistochemistry. Ten fresh NPC and 10 fresh nasopharyngitis specimens were also obtained for determining the protein expression of MAP3K5 by Western blotting. RESULTS: EBERs were positive in all the 53 NPC specimens, and miR-BART22 was positive in 49 specimens; all the 30 nasopharyngitis specimens were negative for EBER or miR-BART22. In the 53 NPC tissues, 50 were negative for MAP3K5 expression in the cancer areas but positive in the adjacent mucosal areas, with the other 3 specimens showing a weak positivity (+). In the 30 nasopharyngitis specimens, 25 showed strong MAP3K5 positivity, 3 showed weak positivity and 2 were negative for MAP3K5 (P<0.001). Western blotting showed that the expression of MAP3K5 protein was significantly higher in nasopharyngitis than in NPC tissues (P=0.029). The expression of MAP3K5 and miR-BART22 was inversely correlated (P<0.001). CONCLUSION: Compared with the adjacent mucosal tissues, NPC tissues have a lower expression of MAP3K5 but a higher expression of miR-BART22. The expression of MAP3K5 and miR-BART22 is inversely correlated, suggesting the possibility of MAP3K5 to serve as target gene of EBV miR-BART22. miR-BART22 may inhibit the expression of MAP3K5, thus reducing the protein phosphorylation of MAPK pathway downstream genes, inhibiting NPC cell apoptosis, preventing their differentiation and promoting their escape from immune surveillance.

[Role of vascular endothelial growth factor receptor 1-positive hematopoietic progenitor cell clusters in human colorectal carcinoma metastasis].

OBJECTIVE: To investigate the relation of vascular endothelial growth factor receptor 1 (VEGFR1)-positive hematopoietic progenitor cell with the metastasis of human colorectal carcinoma. METHODS: Human colorectal cancer cells SW480/M5 were implanted into BALB/c nude mice, and the tumor tissue blocks were re-implanted into the colon of nude mice. The quantity and percentage of VEGFR1-positive hematopoietic progenitor cells and human colorectal cancer cells in the pre-metastatic location were observed with flow cytometry, and the expression of metastasis-related factors was detected using Western blotting. RESULTS: Bone marrow-derived hematopoietic progenitor cells expressing VEGFR1 were found in the common pre-metastatic sites and formed cell clusters before the arrival of the tumor cells, but these cells were not detected in nude mice without tumor implantation. In the course of tumor metastasis, the expression of the proteinases including matrix metalloproteinase 9 and stromal cell-derived factor 1 gradually intensified within the metastatic niche. CONCLUSION: The formation of VEGFR1-positive hematopoietic progenitor cellular clusters is accompanied by the metastasis of human colorectal cancer, and may enhance the expression of metastasis-related factors, suggesting its important role in the invasion and metastasis of colorectal cancer.