The Expression Of Vitamin D Receptor And NF-?B In Rectal Cancer

Objective Rectal cancer is a disease in which malignant cells form in the tissues between the dentate line and the sigmoid colon. The rectal cancer is a very common malignant tumor in our country. There is a rising trend in the incidence rate of rectal cancer during the past few years. It is a serious hazard to human health. Vitamin D is a class of steroid hormones. Vitamin D is close relationship with human health. On the one hand, vitamin D deficiency is more common in the world and is increasingly recognized as a global public health problem. On the other hand, vitamin D may regulate calcium and phosphorus homeostasis, promote bone growth and remodeling, and prevent the occurrence of rickets and osteomalacia. In addition, association between vitamin D deficiency and the incidence of cancer has been approvaled, such as colon cancer. The actions of vitamin D are mediated by vitamin D receptor (VDR). The objective of the present study is to investigate the expression of VDR and nuclear factor (NF)-?B p65 in human rectal cancer and to explore the clinical significance of VDR.Methods The present study analyzed samples that recruited 32 cases and 32 controls from The Second People's Hospital of LuAn city between October 2012 and October 2014. In this study, rectal cancer was diagnosed by clinical and histopathological examination. Thirty-two patients (without colorectal cancer) who underwent colonoscopy were recruited as controls. The specimens of 32 cases of surgically rectal tissue and 32 people of control were collected. Rectal samples were fixed in 10% neutral formalin, and then were embedded in paraffin. Rectal tissue paraffin sections of 4?m were prepared for H&E staining and immunohistochemistry. Morphological changes of rectal tissue were observed using H&E staining. The expression of VDR and NF-?B p65 were detected by immunohistochemistry of streptavidin-perosidase (SP). For immunohistochemistry, paraffin-embedded rectal specimens were deparaffinized and rehydrated in a graded ethanol series. After antigen retrieval and quenching of endogenous peroxidase, sections were incubated with either VDR monoclonal antibody (1:200 dilution, Santa Cruz, USA) or NF-?B p65 monoclonal antibody (1:200 dilution, Santa Cruz, USA) at 4? overnight. The color reaction was developed with HRP-linked polymer detection system and counterstaining with hematoxylin. The positive expression of rectal tissue VDR and NF-?B p65 is yellow or brown yellow in cytoplasm and nuclei. VDR-positive cells and NF-?B p65-positive cells were counted in ten randomly selected fields from each slide at a magnification of×400. The percentage of VDR-positive cells and NF-?B p65-positive cells was analyzed in rectal tissue sections. Positive expression was defined as follows:the percentage of positive cells?5%. Quantitative data were expressed as means ± SD. ANOVA were used to determine differences between different groups. Data that were not normally distributed were assessed for significance using non-parametric tests techniques. All statistical tests were two-sided using an alpha level of 0.05. The present study obtained ethics approval from the ethics committee of West Anhui Health Vocational College. Oral and written consents were obtained from all subjects.Results The demographic characteristics of subjects were compared between rectal cancer and control. No significant difference on age, height, weight and BMI was observed. In addition, although there are no significant difference on serum TBIL, DBIL, IB, TP and GLU levels between two groups, serum CEA and CA199 levels were significantly higher in the case group than those in the control group. In the specimens of 32 cases, the VDR expression of 2 cases (6.25%,2/32) and NF-?B p65 of 6 cases (18.75%,6/32) was positive, but VDR expression of 28 cases (87.50%,28/32) and NF-?B p65 of 29 cases (90.62%,29/32) was positive in the specimens of 32 control. Compared with control, the expressions of VDR and NF-?B p65 were lower in case group and the difference between two groups is statistical significance.Conclusions The lower expression of VDR and NF-?B p65 is observed in rectal cancer tissue.