326P - Biomarker discovery for early prediction of therapy resistance in cervical cancers

Date 18 December 2016
Event ESMO Asia 2016 Congress
Session Poster lunch
Topics Cervical Cancer
Translational Research
Presenter Bok Ai Choo
Citation Annals of Oncology (2016) 27 (suppl_9): ix94-ix103. 10.1093/annonc/mdw585
Authors B.A. Choo1, Z.W. Lee2, W. Zhao2, X. Wang2, J. Ng3, J. Low4, L.W. Deng2
  • 1Radiation Oncology, National University Cancer Institute, Singapore, Singapore 119228 - Singapore/SG
  • 2Biochemistry, National University of Singapore, 117596 - Singapore/SG
  • 3Obstetrics And Gynaecology, National University Cancer Institute, Singapore, Singapore/SG
  • 4Obstetrics And Gynaecology, National University Cancer Institute, Singapore, 119228 - Singapore/SG

Abstract

Background

Cervical cancer is a common and deadly cancer among women worldwide. Resistance to radiation therapy poses a major obstacle in treatment. We hypothesize radiation resistant cells have different molecular signatures (biomarkers) from radiation sensitive cells. Hence, through the study of radiation resistant cell lines, we aim to evaluate the correlation between “stem-like” properties and cell line radiation resistance, to identify a panel of predictive biomarkers for radiation resistance and act as a prognostic tool.

Methods

Parental HPV cells express high oncogenes- E6 and E7 and provide a selective growth advantage. Radiation resistant HeLa(HPV18) and SiHa(HPV16) was generated in-house. Characterization of the HPV cells was carried out with RT-PCR and soft agar assay to study the oncogene expression and transformation ability respectively. To study the “stem-like” property of the cells, they were subjected to “stem condition” and tested for CD44, CD24 surface markers. RNA isolation would be carried out on patient samples. Genes identified in cell line screen would be studied using RT-PCR. The cell line based genetic screen results would be validated against samples from both therapy sensitive and therapy resistant patients,

Results

Positive correlation between the oncogene expression and radiation resistance was found. Microarray analysis of parental cells on functional clustering was done on 35 upregulated genes.11 genes were validated using RT-qPCR and most presented similar trend as microarray analysis, with CDH11 being the most promising. Under stem condition, the amount of stem-like cells (CD44high CD24low or CD49fpositive) increases across the parental, C1, C3 and C5 cells. This suggests a correlation between the amount of stem-like cells and radiation resistance. Levels of SLC2A3 and COL6A1 were also elevated across the parental cells grown in the adherent as well as stem condition. This suggests the potential to be predictive markers of radiation resistance.

Conclusions

We have established and characterized radiation resistant cells through observation of the oncogene expression, transformation ability and stem-like property. Further validation with cervical biopsies samples is underway.

Clinical trial indentification

National University Hospital Singapore Institutional Review Board approved protocol number 2015/00409

Legal entity responsible for the study

National University Hospital Singapore

Funding

National Cancer Institute of Singapore and Terry Fox Foundation

Disclosure

All authors have declared no conflicts of interest.