Our objective was to investigate whether cyclooxygenase-2 (COX-2) expression can predict the patient's response to chemoradiotherapy (CRT) and ensuing prognosis in esophageal squamous cell carcinoma (ESCC). The clinicopathological and follow-up data of 112 patients with ESCC who underwent CRT from January 2001 to June 2006 were analyzed retrospectively. The immunohistochemical expression level of COX-2 was examined for all biopsy specimens of primary tumors, and the correlation of COX-2 expression with the patient's response to CRT and prognosis was examined. COX-2 positive immunostaining was detected in 111 (99.1%) of the patients, including overexpression in 54 (48.2%) patients and low expression in 58 (51.8%) of the patients. The response of tumors with a low level expression of COX-2 (70.7%, 41/58) was significantly higher than that of tumors with COX-2 overexpression (42.6%, 23/54; P = 0.003). Patients with a low level of COX-2 expression had a higher downstaged rate than those with a high level of COX-2 expression (9/13 vs 2/8), but the difference was not statistically significant (P = 0.08). In the definitive CRT group (91 cases), COX-2 overexpression was significantly associated with poor 3-year overall survival (P = 0.028). Multivariate analysis showed that only metastatic stage (nonregional node metastasis) was an independent prognosis factor. The assessment of COX-2 status may provide additional information to identify ESCC patients with poor chances of response to CRT and potential candidates for more individualized treatment.

CD200 is a cell surface glycoprotein that has been implicated in a variety of human cancer cells. It has been proposed as a cancer stem cell (CSC) marker in colon cancer and is closely related to tumor immunosuppression. However, there is little functional data supporting its role as a true CSC marker, and the mechanism by which CD200 contributes to colorectal cancer has not been elucidated. In the present study, CD200+ and CD200- COLO 205 colorectal cancer cells were sorted out by flow cytometry, and colonosphere formation and Transwell migration assays were performed. Affymetrix Human U133 Plus2.0 arrays were used to screen the gene expression profiles of CD200+ and CD200- colorectal cancer cells. The results suggest that there are differentially expressed genes between the two subpopulations, including several important genes that function in cell proliferation, metastasis, apoptosis and the immune response. Pathway analysis revealed that the Wnt, MAPK and calcium signaling pathways were differentially expressed between CD200+ and CD200- cells. Moreover, several key genes upregulated in CD200+ cells were also highly overexpressed in CD44+CD133+ colorectal stem cells compared to the CD44-CD133- fraction of the same cell line. In the present study, we showed for the first time a correlation between CD200 expression and the Wnt signaling pathway in colon cancer cells.

Background: The WNT signaling pathway is involved in the regulation of bone homeostasis, and the effects of WNT signaling pathway related genes (WLS, WNT16 and LRP5) on osteoporosis risk among Chinese postmenopausal women is still unknown. Hence, we performed a case-control study to assess the association of WNT signaling pathway related genes and osteoporosis risk.Methods: This study involved 1026 women (515 osteoporosis patients and 511 controls) of postmenopausal age who were randomly sampled from Xi'an 630 Hospital, Shaanxi Province, China. Eleven genetic polymorphisms in WLS (rs2566755, rs12407028, rs2566752 and rs7554551), WNT16 (rs3779381, rs3801387, rs917727 and rs7776725) and LRP5 (rs2291467, rs11228240 and rs12272917) were selected and genotyped using the Agena MassARRAY iPLEX system. The association of the genetic polymorphisms and osteoporosis risk was assessed by odds ratios and 95% confidence intervals. The Multifactor Dimensionality Reduction (MDR) method was conducted to analyze SNP-SNP interaction.Results: We found that LRP5 polymorphisms (rs2291467, rs11228240 and rs12272917) were significantly associated with a decreased risk of osteoporosis in homozygotes, both in recessive and additive models (P < 0.05). Stratification analysis showed that LRP5 polymorphisms (rs2291467, rs11228240 and rs12272917) significantly decreased the osteoporosis risk in the subgroup of BMI ≤ 24 (P < 0.05) and that individuals carrying a heterozygote genotype of WNT16 polymorphisms (rs3779381, rs3801387, rs917727 and rs7776725) had a higher osteoporosis risk in the subgroup of BMI > 24 (P < 0.05). We observed that three blocks (block 1: rs2566755 and rs12407028, block 2: rs3779381, rs3801387, rs917727 and rs7776725, block 3: rs2291467 and rs11228240), Trs2291467Trs11228240 and Crs2291467Crs11228240 had a strong association with a lower risk of osteoporosis. Additionally, MDR analysis revealed that a four-locus model (rs2566752 and rs2566755 in WLS, rs7776725 in WNT16, rs12272917 in LRP5) was significantly associated with osteoporosis risk. Conclusions: Our findings suggested that WLS, WNT16 and LRP5 genetic polymorphisms were associated with osteoporosis risk among Chinese postmenopausal women.