| 1. |
- Farnebo, Lovisa, et al.
(författare)
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Combining factors on protein and gene level to predict radioresponse in head and neck cancer cell lines
- 2011
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Ingår i: Journal of Oral Pathology & Medicine. - : John Wiley and sons. - 0904-2512 .- 1600-0714. ; 40:10, s. 739-746
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Radiotherapy is the main therapy for head and neck squamous cell carcinoma (HNSCC); however, treatment resistance and local recurrence are significant problems, highlighting the need for predictive markers. In this study, we evaluated selected proteins, mutations, and single nucleotide polymorphisms (SNPs) involved in apoptosis, cell proliferation, and DNA repair alone or combined as predictive markers for radioresponse in 42 HNSCC cell lines. METHODS: The expression of epidermal growth factor receptor, survivin, Bax, Bcl-2, Bcl-XL, cyclooxygenase-2, and heat shock protein 70 was analyzed by ELISA. Furthermore, mutations and SNPs in the p53 gene as well as SNPs in the MDM2, XRCC1, and XRCC3 genes were analyzed for their relation to radioresponse. To enable the evaluation of the predictive value of several factors combined, each cell line was allocated points based on the number of negative points (NNP) system, and the NNP sum was correlated with radioresponse. RESULTS: Survivin was the only factor that alone was significantly correlated with the intrinsic radiosensitivity (r=0.36, p=0.02). The combination of survivin, Bax, Bcl-2, Bcl-XL, cyclooxygenase-2, and the p53 Arg72Pro polymorphism was found to most strongly correlate with radioresponse (r=0.553, p<0.001). CONCLUSION: These data indicate that the intrinsic radiosensitivity of 42 HNSCC cell lines can be predicted by a panel of factors on both the protein and gene levels. Moreover, among the investigated factors, survivin was the most promising biomarker of radioresponse.
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| 2. |
- Farnebo, Lovisa
(författare)
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Predictive markers : for treatment sensitivity in head and neck squamous cell carcinoma
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Head and neck cancer is the sixth most common cancer world wide. In Sweden approximately 850 new cases are diagnosed each year, and two thirds are men. The past decades of improved treatment strategies have unfortunately not significantly improved the five-year survival rates for this group of patients. Therefore, it is important to rapidly find combinations of new and strong predictive markers for treatment response. Different predictive markers have been investigated for decades, without succeeding in finding means to securely predict response to treatment. Models to combine markers are called for.The aim of this thesis was to test multiple predictive markers on both gene and protein level to evaluate their predictive value for radiotherapy and cisplatin response. Furthermore, to combine, and correlate them to treatment response in order to extract the panel of markers that strongest correlated to the investigated treatment. Cell lines derived from 42 patients with head and neck squamous cell carcinoma (HNSCC) were used for protein quantification with Western blot and ELISA of the proteins survivin, Epidermal Growth Factor Receptor, Bcl-2, Bcl-XL, Bax, Bad, Bak, PUMA, Heat shock protein 70, MDM2, p53, SMAD4, Cyclooxygenase-2, and Cyclin D1. The expression of the selected proteins was related to the mean expression of normal oral keratinocytes (NOK) from healthy individuals. Furthermore, mutations in the p53 gene, along with single nucleotide polymorphisms in the genes of p53, MDM2, FGFR4, XRCC1, XRCC3, XPD, and XPC were analysed. To allow a large number of predictive markers on both protein and gene level to be combined and correlated to treatment response, the number of negative points (NNP) model was introduced. Both correlations of sensitivity to radiotherapy and to cisplatin treatment was analysed among the cell lines. In the first paper, including nine cell lines, the panel of EGFR, survivin, and splice site/missense p53 mutations correlated strongest to radioresponse. In paper II, 42 cell lines were used and the combination of survivin, Bcl-2, Bcl-XL, Bax, COX-2, and the p53 Arg72Pro polymorphism was found to most strongly correlate with radioresponse. In paper IV, the panel correlating strongest with cisplatin sensitivity consisted of EGFR, Hsp70, Bax, and Bcl-2 in combination with SNPs in the DNA-repair genes XRCC3 and XPD.The predisposition of the FGFR4 Gly388Arg polymorphism for the development of HNSCC was investigated in paper III. DNA was isolated from 110 tumour biopsies, and restriction fragment length polymorphism analysis showed that 58% of the individuals in the control group carried the FGFR4 Arg388 allele, whereas the frequency in the tumour group was 45%. The Gly388 allele gave a significantly higher risk of developing HNSCC, suggesting Gly388 to be the risk allele for cancer development. Furthermore, a novel mutation was found in the FGFR4 gene. The influence of this new mutation is however unknown.In conclusion, predictive markers for treatment sensitivity need to be combined to receive an accurate prediction of treatment response.
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| 3. |
- Farnebo, Lovisa, et al.
(författare)
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Strong expression of survivin is associated with positive response to radiotherapy and improved overall survival in head and neck squamous cell carcinoma patients
- 2013
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Ingår i: International Journal of Cancer. - : Wiley-Blackwell. - 0020-7136 .- 1097-0215. ; 133:8, s. 1994-2003
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Tidskriftsartikel (refereegranskat)abstract
- Head and neck squamous cell carcinoma (HNSCC) is a malignancy that is associated with severe mortality despite advances in therapy. Todays standard treatment most commonly includes radiotherapy, often combined with chemotherapy or surgery. There are so far no established biomarkers to predict response to radiation, and thus the aim of this study was to investigate a series of markers that could potentially identify HNSCC patients who would benefit from radiotherapy. The selected markers, both proteins (epidermal growth factor receptor, survivin and p53), and single nucleotide polymorphisms (SNPs) in the genes of XRCC3, XRCC1, XPC, XPD, MDM2, p53 and FGFR4 were correlated to the response to radiotherapy and overall survival. Investigations were performed on pretreatment tumor biopsies from patients classified as responders or nonresponders to radiotherapy. Protein expression was examined using immunohistochemistry and the genotyping of specific SNPs was analyzed using PCR-RFLP or pyrosequencing. We found that survivin expression was significantly stronger in the responder group (p = 0.003) and that patients with a strong survivin expression had a significantly better overall survival (p andlt; 0.001). Moreover, downregulation of survivin by siRNA in two HNSCC cell lines significantly decreased their sensitivity to radiation. Among the SNPs analyzed, patients with the XPD Lys751Gln SNP had a significantly shorter overall survival (p = 0.048), and patients with the FGFR4 Gly388Arg SNP had a significantly longer overall survival (p = 0.010). In conclusion, our results suggest that survivin plays an important role in the response to radiotherapy and may be a useful marker for predicting radiotherapy response in patients with HNSCC. less thanbrgreater than less thanbrgreater thanWhats new? Resistance to radiation therapy is a significant problem in the treatment of head and neck squamous cell carcinoma (HNSCC) and has created a need for the discovery of markers predictive of radiotherapy response. One promising marker is survivin, an inhibitor of apoptosis. Here, in pre-treatment biopsies from 40 patients with HNSCC, strong survivin expression was significantly associated with response to radiotherapy and increased overall survival. The data also indicate that single nucleotide polymorphisms in the genes XPD and FGFR4 are other possible predictors of overall survival after radiotherapy.
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