Liver cancer is one of the most common malignant tumors in the world, and at present, China has the highest incidence rate of liver cancer. Liver cancer has an insidious onset, and patients often have no obvious symptoms in the early stage; however, due to the rapid progression of this disease, most patients have developed advanced tumors at the time of diagnosis, and about 10% of patients have microvascular invasion (MVI) at initial pathological diagnosis. Although continuous improvement and progress have been made in the treatment methods for liver cancer, there is no significant reduction in postoperative recurrence rate. Many studies support that MVI is one of the independent risk factors for liver cancer recurrence, and patients with MVI determined by pathological diagnosis often have poor prognosis. However, there is still a lack of preoperative evaluation methods for MVI. This article analyzes and integrates the studies on MVI in the past 3 to 5 years, in order to provide a comprehensive understanding of the research advances in MVI.

Objective To investigate the expression of androgen receptor(AR),ATAD2 in hepatocellular carcinoma(HCC) and the correlations with clinicopathological features,and the role of DHT/AR and ATAD2 in proliferation of HCC cells.Methods The samples of 75 patients with HCC in the First Affiliated Hospital of China Medical University from February 2012 to December 2012 were collected.LM3 and Huh7 cells were divided into control group,DHT group,DHT + CDX (bicalutamide) group and CDX group;and also divided into Ri-ATAD2 group (adding interference fragments) and Ri-C group (adding control vector sequence).Immunohistochemistry was used to detect the expression of AR and ATAD2,and to analyze the correlations between clinical features and survival of patients.Real-time PCR and Western Blot were used to detect the expression of AR and ATAD2,and CCK-8 was used to detect cell proliferation.Results HCC patient samples were grouped according to AR and ATAD2 expression.Compared with low AR expression group (n =31),the ratio of tumor ＜5 cm in high expression group (n =44) was higher,and the ratio of TNM stage Ⅰ + Ⅱ was lower.Compared with low ATAD2 expression group (n=35),the ratio of metastasis and tumor differentiation grade Ⅲ + Ⅳ was higher in high expression group (n=40),and the difference was statistically significant (P ＜ 0.05).The overall survival rate of patients with high expression of ATAD2 was lower than other patients,and the differences were statistically significant (P＜0.05).Multivariate Cox regression analysis showed that ATAD2 expression (HR=1.935,95％ CI:1.066～3.515) and metastasis (HR=2.212,95％ CI:1.059～4.619) were independent predictors of poor prognosis.Compared with LO2 cells,the mRNA and protein level of AR and ATAD2 in LM3 and Huh7 cells were significantly higher,and the differences were statistically significant (P＜0.05).And the proliferation rate of HCC cells increased significantly after 48 and 72 hours compared with the control group,and the differences were statistically significant (P＜0.05).After adding CDX,the proliferation of LM3 and Huh7 induced by DHT was inhibited.DHT enhanced the expression of ATAD2,while CDX inhibited the expression of ATAD2.The expression of ATAD2 protein decreased when LM3 and Huh7 cells were interfered.Compared with Ri-C group,the proliferation of HCC cells in Ri-ATAD2 group decreased significantly after the DHT treatment 48 and 72 hours,and the difference was statistically significant (P＜0.05).Conclusions DHT/AR promoted the proliferation of HCC cells by inducing ATAD2 expression.Modulating ATAD2 expression may be the potential mechanism of DHT/AR in HCC proliferation.

Objective : To investigate the effects of actin like 6A (ACTL6A) knockdown on the proliferation, apop⁃ tosis, migration and invasion of SW1990 cells in pancreatic cancer. Methods : The Oncomine database was used to analyze the expression of ACTL6A mRNA in the tissues of pancreatic cancer and normal pancreas. The plasmid of knockdown ACTL6A and siRNA negative control were established and transfected into SW1990 cell line as siRNA⁃ACTL6A group and siRNA⁃NC group. CCK⁃8, cell apoptosis experiment, Wound healing and Transwell assay were used to determine the effects of ACTL6A knockdown on the proliferation, apoptosis, migration and invasion of SW1990 cells. GSEA predicted a possible pathway regulated by ACTL6A in pancreatic cancer. T⁃test was used between the two groups. Results : The expression of ACTL6A in pancreatic cancer tissues was higher than that in normal pancreatic tissues ( P < 0. 05 ) . The results of CCK⁃8 assay showed that the absorbance of siRNA⁃ACTL6A group at 24 and 48 h were lower than those in the siRNA⁃NC group, and the difference was statistically significant ( t = 5. 840, 8. 454, P < 0. 01) . The results of Wound healing assay and Transwell assay showed that the healing rate and the number of invasive cells in siRNA⁃ACTL6A group were both lower than those in the siRNA⁃NC group. The difference was statistically significant ( t = 3. 960,4. 464, P < 0. 05), but the apoptosis rate of siRNA⁃ACTL6A group was significantly higher than that of the siRNA⁃NC group, and the difference was statistically significant( t = 12. 192, P < 0. 001) . GSEA results showed that the group with high expression of ACTL6A mRNA was up⁃regulated in cell cycle, nucleotide excision repair, base excision repair, DNA replication, pathways in cancer, NOTCH signaling pathway and other related gene sets(P < 0. 05) . These pathways were activated when the expression of ACTL6A was up⁃regulated. Conclusion ACTL6A is highly expressed in pancreatic cancer tissues. ACTL6A knockdown promotes the cell apoptosis of SW1990 cells, and inhibits proliferation, invasion and migration of SW1990 cells. The mechanism of the occurrence and development of ACTL6A in pancreatic cancer is attributed to the activation of cell cycle, nucleotide excision repair, base excision repair, DNA replication, pathways in cancer, NOTCH signaling pathway.