Significance of expression and promoter methylation of LITAF gene in B-cell lymphoma / 中华病理学杂志

<p><b>OBJECTIVE</b>To investigate promoter methylation status of LITAF gene in B-cell lymphoma and to explore transcription regulation of 5-Aza-2'-deoxycytidine (5-Aza-CdR) on LITAF gene.</p><p><b>METHODS</b>One hundred and five paraffin specimens including 54 cases of diffuse large B cell lymphoma (DLBCL), 15 small lymphocytic lymphoma (SLL), 8 mucosa-associated lymphoid tissue lymphoma (MALT) and 6 follicular lymphoma (FL) were included. Five reactive lymphoid hyperplasia samples were collected as control. Methylation status of CpG island in LITAF gene in the specimens and in Raji, Pfeiffer and Daudi cell lines were detected by methylation-specific PCR (MSP). LITAF expression in Raji, Pfeiffer and Daudi cell lines with or without 5-Aza-CdR treatment was detected by Western blot and immunohistochemistry. The inhibitory ratio in the three cell lines was measured by MTT assay.</p><p><b>RESULTS</b>The frequency of LITAF gene methylation in B-cell lymphoma was 89.5% (94/105) . Among them, 3.8% (4/105) showed complete hypermethylation. In control group, however, there was no methylation in CpG island of LITAF gene promoter. The expression of LITAF was recovered or increased along with the cell growth inhibition when the cells exposed to demethylating reagent.</p><p><b>CONCLUSIONS</b>LITAF gene silencing with aberrant CpG methylation is probably one of the critical events to the oncogenesis of B-cell lymphoma, which may have important implications as a candidate marker for diagnosis and target gene therapy.</p>

Features of clinical pathology and immunohistology of lymphoepithelioma-like gastric carcinoma / 中华消化杂志

Objective To analyze and summarize the clinical-pathological features,immunophenotype and prognosis of the lymphoepithelioma-like gastric carcinoma (LELGC).Methods The clinical,radiographic and histological data of four patients with LELGC were retrospectively analyzed.The expression of cytokeratin (CK),CD20,CD3,CD4,CD8,E-cadherin,β-catenin,bcl-2,p16,p53,p63,c-erbB-2,cyclin D1,Ki67 and DNA methyl-transferase 1 (DNMT1) in tumor was detected by Epstein-Barr virus-encoded small RNA (EBER) in situ hybridization and immunohistochemical methods.Results The size of four tumor was 1.8 cm× 1.6 cm,1.5 cm× 2.0 cm,2.5 cm× 2.0 cm and 4.0 cm× 2.5 cm.Under light microscope,tumor cells appeared like cords,small lumps or scattered single infiltration with vacuolized nucleus; clear nucleoli and obvious interstitial lymphocytic infiltration.The results of immunohistochemical examination indicated that in four tumors CK was positive in membrane of all the tumor cells,while EBER was positive in all cell nucleus.The number of lymphocytes with CD3 positive was over those with CD20 positive,which was mainly CD8 positive lymphocytes.The percentage of E cadherin and β-catenin positive in the cell membrane of four tumors was between 10 ％ and 90 ％,and two cases with β-catenin positive in cytoplasm.The expressions of DNMT1,cyclin D1 and bcl-2 were all positive,while p16 and c-erbB-2 were all negative.The expression of p63 was positive in only one case,and p53 was negative in one case.The percentage of Ki67 positive was 40％,15％,60％ and 40％,respectively.Conclusions LELGC is a rare neoplasm with better prognosis.The features of clinical pathology and immunohistology may help to make a correct diagnosis.

Comparison between the adeno-associated virus and lentivirus as small interfering RNA carrying vector / 国际外科学杂志

Objective To construct recombinant adeno-associated virus and lentivirus carrying siRNA of TIMP-1 and to investigate the efficiency of infection and short-term inhibitory effect of TIMP-1 gene expres-sion on rat hepatic stellate cells. Methods One pair of siRNA which could effectively inhibit expression of the TIMP-1 gene in HSC-T6 was screened and cloned into AAV vector and lentiviral vector to construct the recombinant AAV/siRNA-TIMP-1/GFP and Lenti/siRNA-TIMP-1/GFP. AAV/GFP and Lenti/GFP as neg-ative control were also obtained. Experiments were assigned to five groups: AAV/siRNA-TIMP-1/GFP, AAV/GFP, Lenti/siRNA-TIMP-1/GFP, Lenti/GFP group and mock group. Rat HSC-T6 cells were infected by these recombinant viruses at a concentration of MOI by 10. To monitor the efficiency of infection, fluores-cence microscope and flow cytometer were used. After 7 d post-infection, Western blot was used to detect the TIMP-1 protein expression. Results HSC-T6 had no significant changes after infection. The efficiency of infection in AAV/GFP and Lenti/GFP group were 72.7% and 70.0%, AAV/siRNA-TIMP-1/GFP and Lenti/siRNA-TIMP-1/GFP group were 64.58% and 61.86%. The protein expression levels of TIMP-1 in HSC-T6 cells at 7 d post-infection by the recombinant AAV and Lentivirus were decreased 40.0% compared with those in mock control and normal HSC-T6 (P<0.05). Conclusion Recombinant AAV/siRNA-TIMP-1/GFP and Lenti/siRNA-TIMP-1/GFP could effectively infect HSC-T6 with similar efficiency and suppress the expression of TIMP-1 in rat HSC-T6 remarkably.

The relationship between TMPRSS2-Ets fusion gene and prostate cancer / 国际肿瘤学杂志

A unique fusion between the TMPRSS2 gene and the Ets genes ERG,ETV1、ETV4 or ETV5 has been described in prostate cancer, TMPRSS2-ERG is the most high frequency of all. Until now more than 20 kinds of TMPRSS2- ERG hybrid transcripts are found, and they encode 9 kinds of proteins. Deletion is the main mechanism of fusion. Fusion gene can be used to make a diagnosis of prostate cancer , direct clinical medication , then fusion type, fusion number and transcriptive type are also associated with prognosis of dis-ease. So, besides of serum PSA, Gleason score, TMPRSS2- ERG is expected to be another important predicator of prognosis.