title: Identification and validation of genes involved in cervical tumourigenesis.
abstract: BACKGROUND
  Cervical cancer is the most common cancer among Indian women. This cancer has well defined pre-cancerous stages and evolves over 10-15 years or more. This study was undertaken to identify differentially expressed genes between normal, dysplastic and invasive cervical cancer.
  
  
  METHODS
  A total of 28 invasive cervical cancers, 4 CIN3/CIS, 4 CIN1/CIN2 and 5 Normal cervix samples were studied. We have used microarray technique followed by validation of the significant genes by relative quantitation using Taqman Low Density Array Real Time PCR. Immunohistochemistry was used to study the protein expression of MMP3, UBE2C and p16 in normal, dysplasia and cancers of the cervix. The effect of a dominant negative UBE2C on the growth of the SiHa cells was assessed using a MTT assay.
  
  
  RESULTS
  Our study, for the first time, has identified 20 genes to be up-regulated and 14 down-regulated in cervical cancers and 5 up-regulated in CIN3. In addition, 26 genes identified by other studies, as to playing a role in cervical cancer, were also confirmed in our study. UBE2C, CCNB1, CCNB2, PLOD2, NUP210, MELK, CDC20 genes were overexpressed in tumours and in CIN3/CIS relative to both Normal and CIN1/CIN2, suggesting that they could have a role to play in the early phase of tumorigenesis. IL8, INDO, ISG15, ISG20, AGRN, DTXL, MMP1, MMP3, CCL18, TOP2A AND STAT1 were found to be upregulated in tumours. Using Immunohistochemistry, we showed over-expression of MMP3, UBE2C and p16 in cancers compared to normal cervical epithelium and varying grades of dysplasia. A dominant negative UBE2C was found to produce growth inhibition in SiHa cells, which over-expresses UBE2C 4 fold more than HEK293 cells.
  
  
  CONCLUSIONS
  Several novel genes were found to be differentially expressed in cervical cancer. MMP3, UBE2C and p16 protein overexpression in cervical cancers was confirmed by immunohistochemistry. These will need to be validated further in a larger series of samples. UBE2C could be evaluated further to assess its potential as a therapeutic target in cervical cancer.
authors.affiliation: Dept of Molecular Oncology, Cancer Institute (WIA), Chennai, India. drtrajkumar@gmail.com
authors.forename: Thangarajan
authors.initials: T
authors.lastname: Rajkumar
authors.forename: Kesavan
authors.initials: K
authors.lastname: Sabitha
authors.forename: Neelakantan
authors.initials: N
authors.lastname: Vijayalakshmi
authors.forename: Sundersingh
authors.initials: S
authors.lastname: Shirley
authors.forename: Mayil Vahanan
authors.initials: MV
authors.lastname: Bose
authors.forename: Gopisetty
authors.initials: G
authors.lastname: Gopal
authors.forename: Ganesharaja
authors.initials: G
authors.lastname: Selvaluxmy
mesh_terms: D052685:Alphapapillomavirus / Q000235:genetics; D002471:Cell Transformation, Neoplastic / Q000235:genetics* / Q000473:pathology; D002478:Cells, Cultured; D004279:DNA, Viral / Q000235:genetics; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D052138:Genes, Neoplasm; D005814:Genes, Viral; D006367:HeLa Cells; D006801:Humans; D046228:Microarray Analysis; D002583:Uterine Cervical Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D002578:Uterine Cervical Dysplasia / Q000235:genetics* / Q000378:metabolism / Q000473:pathology
chemical_list: D004279:DNA, Viral