Aims HDAC2 gene was cloned into pEGFP-C2 vector to explore the efficiency of the plasmid trans-fection in renal fibroblasts COS-7 cells to identify the expression of both mRNA and protein levels and to ob-serve the distribution of the protein. Methods The HDAC2 cDNA was amlified by PCR and cut with the double enzyme Xho I and BamH I, then inserted into the eukaryotic expression vector pEGFP-C2 with T4 en-zyme. The recombinant vector was verified by PCR, restriction enzymes cut and sequencing identification. Then it was transfected into COS-7 cells and the ex-pression of pEGFP-C2-HDAC2 was monitored by fluo-
rescence microscope and PCR. Results Fragments of HDAC2 could be seen after dealt with double diges-tion, and GFP could also be detected in the transfected COS-7 cells. HDAC2 gene expression could be detec-ted by PCR and Western blot. The fusion expression of pEGFP-C2-HDAC2 could be detected by Western blot. Conclusion Eukaryotic expression vector of HDAC2 has been successfully constructed, the fusion expres-sion of HDAC2 and GFP protein can be detected in COS-7 cells.

Objective: To investigates the role of piwi-interacting RNAs (piRNA) in the occurrence and development of hepatocellular carcinoma. Methods: Second-generation small RNA sequencing was performed on cancer and paracancerous tissues, metastatic and non-metastatic liver cancer tissues of patients with liver cancer, and the sequencing data were filtered out for the common RNA sequences to be repeated. The piRNA predictor was used to forecast the possible new piRNA merged with the downloaded known piRNA to screen out distinction. A miRanda algorithm was used to predict the corresponding target genes and functional enrichment analysis. piRNA was selected for experimental functional (migration) analysis. An independent t-test was used to compare means between the two groups. Results: 66 772 piRNAs (known 149) were obtained by sequencing. 241 piRNAs were found in cancer and paracancerous tissues, and 1 634 piRNAs were found in metastatic and non-metastatic tumors. Analysis of the GO and KEGG pathways of the target genes of differential piRNAs revealed that they were mainly involved in cell adhesion. An experimental functional analysis was performed on the selected Pirna (PIR1/97), which showed that it promoted the migration of hepatoma cells (LM3: t = 8.829, P < 0.05; PLC: t = 7.318, P < 0.05). Conclusion The expression levels of piRNA in hepatocellular carcinoma patients with cancer and paracancerous tissues, metastasis and non-metastatic liver cancer tissues are different and it could be entailed in the metastasis process of hepatocellular carcinoma. Hence, experimental functional analysis is required for research and experimental confirmation.

Objective: To further understand the interaction protein spectrum of heterogeneous ribonucleoprotein AB (hnRNP AB), and to investigate their clinical significance in hepatocellular carcinoma (HCC). Methods: We carried out mass spectrometry to reveal the specific peptides of KRAB-associated protein 1 (Kap1) and hnRNPAB, and verified their interaction by immunocoprecipitation and western blotting. Expression of hnRNPAB/Kap1 proteins were detected by immunohistochemical staining in the tissue microarrays. Categorical data were analyzed by the chi square test or Fisher exact test; enumeration data between groups were compared using Student t-test or Wilcocon signed rank test; the cumulative recurrence and survival rates were evaluated using the Kaplan-Meier method and the differences were assessed using the log-rank test. Results: We identified Kap1 as a molecular partner for hnRNPAB in HCCLM3 cells and HepG2 cells as well. We found that the 5-year survival rate of the Kap1high patients was significantly lower than the survival rate of those of the Kap1low group (36% vs 59% , HR = 1.67, P < 0.001). Similarly, Kap1high HCC patients had the poorest prognosis at 5-years, with higher cumulative recurrence rate than Kap1low patients (72% vs 54%, HR = 1.66, P = 0.001). Univariate and Multivariate analyses revealed that hnRNPAB /Kap1 alone (HR = 1.35 /1.28, P = 0.001) or in combination with Kap1 (HR =1.24 /1.27, P < 0.05) were independent prognostic indicators for overall survival and time to recurrence. Conclusion In HCC cells, hnRNPAB and Kap1 form protein complexes. The expression levels of hnRNPAB alone or in combination with Kap1 in HCC patients are important because they provide not only a predictor for HCC prognosis but also a therapeutic target for future studies.