title: [Promoting effect of Chlamydia pneumoniae infection on human laryngeal carcinoma HEp-2 cell adhesion and migration].
abstract: OBJECTIVE
  To explore the effect of Chlamydia pneumoniae (C.pn) infection on human laryngeal carcinoma cell line HEp-2 cell adhesion and migration, to further clarify the role and mechanism of C.pn infection in tumor metastasis.
  
  
  METHODS
  HEp-2 cells were infected with C.pn after the culture and propagation of C.pn. The cytopathic effect was observed by microscopy. Morphological characteristics of C.pn inclusions in HEp-2 cells were examined by fluorescence microscopy and acridine orange staining. The ultrastructural changes of C.pn inclusions in the HEp-2 cells were examined by transmission electron microscopy (TEM). Cell adhesion assay was performed to investigate the effect of C.pn infection on the adhesion of HEp-2 cells to collagen I. Wound-healing assay and transwell assay were performed to explore the effect of C.pn infection on HEp-2 cell migration.
  
  
  RESULTS
  At 72 h post-infection, C.pn infected-HEp-2 cells were swollen and partially desquamated. Numerous vacuoles (inclusions) were observed and C.pn inclusions occupied almost the whole cytoplasm of the HEp-2 cells. Grape-like C.pn inclusions were observed in the HEp-2 cells stained with acridine orange under a fluorescence microscope at 72 h after infection. Under TEM, there were more mature pear-shaped elementary bodies, but less larger and round reticulate bodies in the HEp-2 cells infected with C.pn for 72 h. In the cell adhesion assay, the A value in C.pn infection group was 0.669 ± 0.011, significantly higher than that in the control group (0.558 ± 0.005) at 2 h after infection (P < 0.001). The cell adhesion ratio in the C.pn infection group was 119.89%. The migration distance of C.pn infected-HEp-2 cells in the wound-healing assay was significantly longer than that of control cells at 24 h after infection (P < 0.05). HEp-2 cells infected with C.pn for 12 h migrated more than the control cells in the transwell assay (23.40 ± 2.41 vs 10.40 ± 1.67) (P < 0.001).
  
  
  CONCLUSIONS
  C.pn infection can significantly promote HEp-2 cell adhesion to collagen I and migration of HEp-2 cells, indicating that C.pn infection may play an important role in promoting the metastasis of laryngeal cancer.
authors.affiliation: Department of Pathophysiology, Basic Medical College, Tianjin Medical University, Tianjin 300070, China. lijunwz@hotmail.com
authors.forename: Li-Jun
authors.initials: LJ
authors.lastname: Zhang
authors.forename: Li
authors.initials: L
authors.lastname: Hong
authors.forename: Ning
authors.initials: N
authors.lastname: Chen
authors.forename: Bing-Ling
authors.initials: BL
authors.lastname: Shen
authors.forename: Yan-Qiu
authors.initials: YQ
authors.lastname: Deng
authors.forename: Wei
authors.initials: W
authors.lastname: Quan
authors.forename: Bei-Bei
authors.initials: BB
authors.lastname: Wang
authors.forename: Li-Jun
authors.initials: LJ
authors.lastname: Zhang
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000382:microbiology / Q000473:pathology*; D002448:Cell Adhesion; D045744:Cell Line, Tumor; D002465:Cell Movement; D023521:Chlamydophila Infections / Q000382:microbiology / Q000503:physiopathology; D016993:Chlamydophila pneumoniae; D006801:Humans; D007822:Laryngeal Neoplasms / Q000382:microbiology / Q000473:pathology*