ABSTRACT
Objective · To investigate the effect of Toll-like receptor 4 (TLR4) in the pathological injury in fat embolism mice model. Methods · One hundred and twenty male C57BL/6 mice were randomly divided into 10 groups. One group was set as blank control group, and others were injected separately with 1, 2…9 μL/g of allogeneic perirenal fat via tail vein, respectively. The mortality of each group was counted, median lethal dose (LD50) of fat injection in mice was calculated by Bliss method, and the fat embolism LD50 mice model was established. The TLR4 protein expression in the pulmonary tissue of surviving mice was detected by Western blotting. Sixty male C57BL/6 mice were randomly divided into the control group (the same dose of saline was given via tail vein) and the experimental groups (group 2 h, group 8 h, group 24 h and group 48 h, the LD50 fat was given via tail vein).The TLR4 protein expression at different time after fat injection was detected by Western blotting. The mortality of 20 TLR4 gene-knockout mice (TLR4-/-mice) was recorded and compared with 60 wild-type mice after LD50 fat injection. Results · The LD50 of fat embolism mice model was (3.93±0.78) μL/g.After the injection of 1-7 μL/g fat, the expressions of TLR4 protein in the pulmonary tissue of all seven groups were significantly increased, compared with the control group (all P=0.000). In the fat embolism LD50 mice model, compared with the control group, the expressions of TLR4 protein in group2 h were significantly increased (P=0.005). Then, expression level of TLR4 protein was gradually reduced after 2 h, and there was no significant difference between the control group and group 48 h. The mortality of TLR4-/- mice injected with LD50 fat was lower than that of wild-type mice (P=0.043).Conclusion · TLR4 protein involves in the pathologic process of fat embolism syndrome. The knockout of TLR4 gene can reduce the mortality of fat embolism mice. TLR4 and its correlated non-infectious inflammatory response may be an important molecular mechanism of biochemical injury in fat embolism syndrome. Blocking the activation of TLR4-mediated signaling pathway can significantly improve the prognosis, which provides new basis for the prevention, evaluation and treatment of fat embolism syndrome.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the possible association between the single nucleotide polymorphisms (SNPs) (C-8343G, C-1863T and R72P) in TP53 gene and susceptibility to liver metastases of colorectal cancer (CRC) in a Chinese population.</p><p><b>METHODS</b>The genotypes of each SNP in TP53 gene were determined by either TaqMan assays or PCR-based restriction fragment length polymorphism (RFLP) method in 121 colorectal cancer patients with liver metastases and sex-, age-matched 280 cases with nonmetastatic CRC as a control. Immunohistochemical staining for P53 was performed on paraffin-embedded sections. Odds ratios (ORs) for colorectal liver metastases and 95% confidence intervals (CIs) from unconditional logistic regression models were used to evaluate relative risks.</p><p><b>RESULTS</b>No significant association of C-8343G or C-1863T with colorectal liver metastases risk was observed. However, the R allele of the TP53 R72P polymorphism was more frequently found in metastatic cases than in nonmetastatic cases (P= 0.037). When compared with PP homozygotes, the ORs of metastases for RP heterozygotes was 2.21 (95% CI: 1.13-4.33), for RR homozygotes was 2.26 (95% CI: 1.03-4.94), and for carriers of the 72R allele (RP or RR genotype) was 2.22 (95% CI: 1.16-4.26). Stratified analysis indicated that carrying the 72R allele had a more pronounced increase in colorectal liver metastases risk among patients with positive P53 expression tumors (OR= 3.28, 95% CI: 1.21-8.88), whereas no significantly increased metastases risk was found in patients with negative P53 expression tumors (OR= 1.37, 95% CI: 0.52-3.62).</p><p><b>CONCLUSION</b>The R allele of the TP53 R72P polymorphism may contribute to the etiology of liver metastases in CRC patients, particularly among those with positive P53 expression tumors. Both TP53 C-8343G and C-1863T may be not associated with colorectal liver metastases risk.</p>
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Colorectal Neoplasms , Genetics , Genes, p53 , Genetics , Genetic Predisposition to Disease , Genetics , Genotype , Liver Neoplasms , Genetics , Polymerase Chain Reaction , Polymorphism, Genetic , Genetics , Polymorphism, Restriction Fragment Length , GeneticsABSTRACT
<p><b>OBJECTIVE</b>To evaluate the association between p53 codon 72 polymorphism (R72P) and the risk of colorectal liver metastases.</p><p><b>METHODS</b>The p53 R72P genotype was identified by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method in 78 consecutive colorectal cancer patients with liver metastases and 214 age- and sex-matched cases with nonmetastatic colorectal cancer.</p><p><b>RESULTS</b>The R allele of the p53 R72P polymorphism was more frequently found in metastatic cases than in nonmetastatic cases (P=0.075). Carriers of the 72R allele had a 2.25-fold (95% CI (confidence interval)=1.05 to approximately 4.83) increased risk of liver metastases. On the stratification analysis, 72R-carrying genotype conferred a 3.46-fold (95% CI=1.02 to approximately 11.72) and a 1.05-fold (95% CI=0.36 to approximately 3.08) increased risk of liver metastases for p53 overexpression-positive and negative colorectal cancers, respectively.</p><p><b>CONCLUSION</b>These results demonstrate for the first time that the 72R allele of the p53 polymorphism has an increased risk for liver metastases in colorectal cancers positive for p53 overexpression.</p>