title: [Association of CD133 expression and sensitivity of rectal cancer to preoperative radiotherapy].
abstract: OBJECTIVE
  To determine the association of CD133 expression with the sensitivity to radiotherapy among rectal cancer patients.
  
  
  METHODS
  The clinical data of 32 rectal cancer patients was retrospectively collected for patients who received a short-term preoperative radiotherapy(5 Gy/d,×5 d) from 2008 to 2010. Pretreatment tumor biopsies were immunostained for CD133 expression. Rectal cancer regression grade (RCRG) was used to evaluate the sensitivity of the rectal cancer to preoperative radiotherapy. The correlation of CD133 expression and sensitivity to radiotherapy was analyzed.
  
  
  RESULTS
  CD133 differentially expressed in rectal cancer tissue with 17 high expression and 15 low expression. The expression of CD133 was associated with the differentiation of rectal cancer with higher expression of CD133 among poorly differentiated rectal cancers(P<0.05). Among the CD133-high patients, two patients showed 1st RCRG, five patients showed 2nd RCRG and ten patients showed 3rd RCRG. For the CD133-low patients, there were five 1st RCRG, seven 2nd RCRG and three 3rd RCRG. There was a significant association between CD133 expression and sensitivity to radiotherapy (P=0.037). Multivariate logistic regression analysis showed that the expression level of CD133(P=0.027) and the differentiation of rectal cancer(P=0.046) were independent predictive factors for the sensitivity of rectal cancer to radiotherapy.
  
  
  CONCLUSIONS
  Correlation between CD133 expression and sensitivity to radiotherapy of rectal cancer may exist, which may be helpful in predicting the sensitivity of rectal cancer to preoperative radiotherapy.
authors.affiliation: Department of Coloproctology, The Third People's Hospital of Hangzhou, Hangzhou, China.
authors.forename: Jian-ming
authors.initials: JM
authors.lastname: Qiu
authors.forename: Guan-gen
authors.initials: GG
authors.lastname: Yang
authors.forename: Xin-jian
authors.initials: XJ
authors.lastname: Lu
authors.forename: Xing
authors.initials: X
authors.lastname: Wang
authors.forename: Zhong
authors.initials: Z
authors.lastname: Shen
authors.forename: Xiu-feng
authors.initials: XF
authors.lastname: Zhang
mesh_terms: D000071916:AC133 Antigen; D015703:Antigens, CD / Q000378:metabolism*; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001706:Biopsy; D003131:Combined Modality Therapy; D006023:Glycoproteins / Q000378:metabolism*; D006801:Humans; D010455:Peptides / Q000378:metabolism*; D012004:Rectal Neoplasms / Q000378:metabolism* / Q000532:radiotherapy; D012189:Retrospective Studies
chemical_list: D000071916:AC133 Antigen; D015703:Antigens, CD; D014408:Biomarkers, Tumor; D006023:Glycoproteins; C000606023:PROM1 protein, human; D010455:Peptides