Purpose:To investigate the effects of tumor suppressor gene p53 on the activity of telomerase/hTERT in human HCC-9204 cell line.Methods:Lipofection-mediated gene transfection method was used to transfect wild-type p53(wt-p53) gene into HCC 9204 cell which expresses telomerse /hTERT and carries mutant-type p53 gene. The expression of p53 was confirmed by Western blot. Both the telomerase activity and hTERT mRNA expression were detected by PCR-ELISA,TRAP-silver staining,in-situ hybridization and RT-PCR methods. The apoptotic appearance was examined by FCM.Results:Higher telomerase activity and hTERT mRNA level were detected in HCC-9204,and they were markedly inhibited after transfection with wt-p53. Meanwhile,decreasing level of bcl-2 protein and appearance of apoptosis were also shown in the transfected cells.Conclusions:Over expression of the exogenous wt-p53 gene does suppress both telomrease activity and hTERT mRNA expression in HCC cell line. There is a p53-dependent regulatory pathway for activation and expression of telomerase/hTERT in HCC.

Objective　To explore the expression and significance of p21WAF1 and p53 in HCC. Methods　Immunohistochemical method (IHC) was used to localize and semi-quantitate the proteins of p21WAF1 and p53 and to observe the relationship between the expression of p21WAF1 and the different histopathologic characters in 38 patients of HCC and their peri-cancer tissue as well as 5 normal liver tissue. Results　Of all 38 cases, both p21WAF1 and p53 expression were significantly higher in tumor than that in corresponding non-tumors liver tissue; 14 (36.8 %) of 38 cases showed p21WAF1 positive staining, 28 cases (73.7 %) were p53 positive, p21WAF1＋/p53＋ or p21WAF1-/p53－ were observed in 18, while 20 cases showed p53＋/p21WAF1－ or p53－/p21WAF1＋. p21WAF1＋ was seen in 1 of 38 (2.6 %) corresponding non-cancerous tissue and 2 of 5 normal liver tissue. p53 protein was not detected neither in the non-tumorous tissue nor in normal liver. No significant association was found between the expressions of p21WAF1 and p53(P＞0.05) in HCC. Their was no significant correlation between p21WAF1 or p53 expression and the different histopathologic characters of tumor (differentiating grades, intrahepatic metastasis and/or cancerous thrombi within portal veins). Conclusion　Both p21WAF1 and p53 proteins are over expressed in HCC than that in corresponding non-tumorous liver tissue, but there is no relationship between them. Both p53-independent and p53-dependent mechanism may play a role in regulating p21WAF1 expression in HCC. p21WAF1 immunostaining cannot be used to assess the status of p53 in any given cell or tissue.

Purpose: Optical coherence tomography (OCT) has the potential for in vivo clot composition characterization in difficult mechanical embolectomy cases. We performed an in vitro study to determine the OCT characteristics of red blood cells (RBCs) and fibrin rich clots. Materials and Methods: Analogues of 5 compositions of clots (5% to 95% RBCs from Group A to E) were created from human blood. The blood mixture was injected into the bifurcation of a 3D printed bifurcated silicone tube. The OPTISTM Integrated System (St. Jude Medical Inc.) was used to identify the magnitude of OCT signals from different compositions of clots. Martius Scarlett Blue trichrome (MSB) staining was performed to confirm the composition of RBCs and fibrin in each clot. Results: Group A and B showed less signal attenuation (less than 30%) from its surface to the inside, which indicated high penetration (low-back scattering). Group C indicated intermediate signal attenuation (60%) from its surface to inside the clots, in which signals were found even at the periphery of the clot. Group D and E were superficially signal rich with more signal attenuation (more than 80%) from its surface to the inside indicating low penetration (high-back scattering). Signal-free shadowing was shown in 3 clots in Group E. MSB staining indicated color change (from red in fibrin-rich clots to yellow in RBC-rich clots). Conclusion Different compositions of clots can be assessed using OCT. Fibrin-rich clots have homogeneous signals with high penetration, while RBC-rich clots can be recognized as superficially signal rich with low penetration.