Wang et al. BMC Cancer 2010, 10:415 http://www.biomedcentral.com/1471-2407/10/415 Table 3 Univariate and multivariate analysis of different prognostic parameters for PFS of GBM patients Variables Age* Gender Male Female KPS* Extent of resection* TLR9 expression Low High *Mean ± standard deviation Value 44.96 ± 12.54 39(56.52%) 30(43.48%) 78.00 ± 16.26 1.30 ± 0.77 38(55.07) 31(44.93) Univariate analysis p 0.682 0.086 0.834 0.149 0.013 Multivariate analysis Hazard ratio (95% CI) 1.000 (0.982-1.018) 0.620 (0.238-1.617) 1.014 (0.996-1.033) 1.456 (0.497-4.269) 3.205 (1.152-8.920) Page 7 of 11 p 0.983 0.329 0.129 0.174 0.026 [23-25]. Mitchell et al [25] found a high percentage (more than 90%) of GBM tumors, not surrounding nor- mal brain, are associated with HCMV nucleic acids and proteins. Thus a virus or inflammation related biomar- ker may be predictive of glioma progression and devel- opment. It was demonstrated that HCMV infection strongly induced TLR9 expression in fibroblast [26]. TLR9 belongs to Toll like receptors, which are a family of pattern recognition receptors that sense highly con- served structures from microorganisms [27]. Among the TLR family, TLR9 recognizes the ODN with CpG motif. After binding with the ligand, TLR9 signal pathway leading to subsequent downstream activation of the NF B, and MAPK signaling pathways [28], which may responsible for the proinflammatory or progrowth microenvironment of tumor. Recent studies suggested that many different tumor cell types, such as colon [29], prostate [10], breast [7], lung [9] et al express TLR9 and that TLR9 signaling promotes tumor growth, survival and immune evasion. Thus we proposed that The TLR9 pathway may also exist and activated in glioma tissues. There are controversy results for the expression of TLR9 in glioma cells, Grauer et al [13] showed that TLR9 are essentially absent at GL261 cells, While Anda- loussi et al [14] found a strong expression of TLR9 in GL261 cells with RT-PCR and FCM analysis. This dif- ference was most likely not caused by the contamination of genomic DNA at RT-PCR analysis, since Andaloussi Figure 3 Proliferation of glioma cell lines in response to CpG ODN(ODN 2006). Human U87 glioma cell line, human U251 glioma cell line, and rat C6 glioma cell line were incubated with CpG ODN(10 uM), CpG ODN Control(10 uM) or same volume of PBS. The analysis was performed in triplicate and cell growth was measured at 24, 48, 72 hours with an ELISA reader at 490 nm, data was represented as OD value. Bars refer to the standard error of the mean value. Comparison between groups was made by using student’s t test, P ≤ 0.05 was defined as significant.