[Alteration of Wnt3a overexpression and its early monitoring value during hepatocellular carcinogenesis].

Objective: To investigate the dynamic expression pattern of carcinoembryonic Wnt3a and its early monitoring value using a hepatocellular carcinoma model. Methods: Forty-eight Sprague Dawley (SD) rats were fed with pellet feed containing 2-acetylaminofluorene (2-AAF, 0.05%) to induce hepatocarcinogenesis, and control rats were fed a pellet diet. Liver tissue and blood samples were collected every two weeks. Liver tissues were pathologically examined using HE staining and grouped. The gene and Wnt3a mRNA expression were analyzed by genome-wide microarray. The expression and distribution of Wnt3a in liver tissue were analyzed by immunohistochemistry. Wnt3a concentration in liver tissue and serum was quantified by enzyme-linked immunosorbent assay. Statistical methods such as χ2 test, Mann-Whitney test and analysis of variance were used to analyze the differences between groups. Results: According to the pathological examination results, the rat livers were divided into four groups: control, hepatocyte degeneration, precancerous lesions and hepatocellular carcinoma. Genome-wide expression profiling analysis and comparison with the control group revealed that 268 and 312 genes were up-regulated and 57 and 201 genes were down-regulated in the precancerous and cancerous group when signal logarithm ratio (SLR) was >8 log2cy5/cy3, and these significantly altered genes mainly involved in cell proliferation, signal transduction, tumor metastasis, and apoptosis. The expression of Wnt3a at mRNA level was significantly increased in all stages of cancer induction, including degeneration group (1.15±0.24, q=8.227), precancerous group (1.85±0.18, q=12.361) and cancerous group (2.59±0.55, q=18.082). Compared with the control group (0.25±0.11, F=121.103, P<0.001), the degeneration group, the precancerous group and the liver cancer group were up-regulated by 4.6, 7.4 and 10.4-folds, respectively. Immunohistochemistry showed that compared with the control group, the positive rate of Wnt3a in the degeneration group was 66.7% (12/18, χ2=10.701, P=0.001), and both the precancerous and liver cancer groups were positive (9/9, χ2=17.115, P<0.001). Wnt3a expression was gradually increased in liver and blood samples during the process of carcinogenesis, and the difference between two groups was statistically significant (F=176.711, P<0.001). Wnt3a overexpression was secreted into blood stream via cancerous liver tissue, and there was a linear correlation between Wnt3a levels in blood and liver samples (r=0.732, P<0.001). Conclusions: Wnt3a overexpression is closely related with hepatocellular carcinogenesis, and thus may become a new monitoring marker.

Human umbilical cord mesenchymal stem cell-derived exosomes carrying hsa-miRNA-128-3p suppress pancreatic ductal cell carcinoma by inhibiting Galectin-3.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal malignant tumors of the digestive system. Many patients are diagnosed at an advanced stage and lose eligibility for surgery. Moreover, there are few effective methods for treating pancreatic ductal cell carcinoma. Increasing attention has been given to microRNAs (miRNAs) and their regulatory roles in tumor progression. In this study, we investigated the effects of exosomes extracted from human umbilical cord mesenchymal stem cells (HUCMSCs) carrying hsa-miRNA-128-3p on pancreatic cancer cells. METHODS: Based on existing experimental and database information, we selected Galectin-3, which is associated with pancreatic cancer, and the corresponding upstream hsa-miRNA-128-3p. We extracted HUCMSCs from a fresh umbilical cord, hsa-miRNA-128-3p was transfected into HUCMSCs, and exosomes containing hsa-miRNA-128-3p were extracted and collected. The effect of exosomes rich in hsa-miRNA-128-3p on pancreatic cancer cells was analyzed. RESULTS: The expression of Galectin-3 in normal pancreatic duct epithelial cells was significantly lower than that in PDAC cell lines. We successfully extracted HUCMSCs from the umbilical cord and transfected hsa-miRNA-128-3p into HUCMSCs. Then we demonstrated that HUCMSC-derived exosomes with hsa-miRNA-128-3p could suppress the proliferation, invasion, and migration of PANC-1 cells in vitro by targeting Galectin-3. CONCLUSION: Hsa-miRNA-128-3p could be considered as a potential therapy for pancreatic cancer. We provided a new idea for targeted therapy of PDAC.

[Value of abnormal expression of Krüppel-like zinc-finger protein transcription factor 5 in the diagnosis and prognosis of liver cancer].

Objective: To explore the value of Krüppel-like factor 5 (KLF5), a family member of the zinc finger protein transcription factor, in the diagnosis and prognostic evaluation of hepatocellular carcinoma (HCC). Methods: Cancerous and non-cancerous tissues were collected from 126 cases after HCC surgery by self-matching method with microarray fabrication. Immunohistochemistry was used to analyze the expression of KLF5, clinicopathological characteristics and prognostic value. The sera of 222 cases with chronic liver disease were collected and their KLF5 levels were quantitatively determined by enzyme-linked immunosorbent assay (ELISA). Simultaneously, 40 normal human sera were used as controls to evaluate the value of abnormal KLF5 in the diagnosis and differentiation of benign and malignant liver diseases. T-test, Z-test and χ (2) test were performed on the data. Results: The positive expression rate of KLF5 in the HCC group was 95.2% (120/126), which was significantly higher than the non-cancerous group 38.9% (49/126; χ (2) = 14.385, P < 0.001). KLF5 expression was significantly correlated with TNM stage (stage I 35%, stage II 40%, stage III 74.4%, stage IV 78.1%), tumor size, alpha fetoprotein (AFP) concentration, portal vein embolism, HBV infection and 5-year survival rate. Univariate/multivariate analysis showed that KLF5 high expression was an independent predictor of HCC prognosis. The serum KLF5 level was significantly higher in HCC patients than liver cirrhosis, chronic hepatitis and normal control group (P < 0.001). With the serum KLF5 > 800 ng/ml and AFP > 25 µg/L as limit, the positive rates for HCC diagnosis were 90.48% and 73.81%, respectively, which were lower than the AFP specificity and false positive rate, and was helpful for the differential diagnosis of benign and malignant liver diseases. Conclusion: The overexpression of KLF5 in liver cancer tissues and blood is closely related to the HCC clinical stage and prognosis. Moreover, KLF5 analysis is helpful for HCC diagnosis and differential diagnosis.

MiR-34c downregulation leads to SOX4 overexpression and cisplatin resistance in nasopharyngeal carcinoma.

BACKGROUND: A major cause of disease-related death in nasopharyngeal carcinoma (NPC) is the development of distant metastasis (DM) despite combination chemoradiotherapy treatment. We previously identified and validated a four microRNA (miRNA) signature that is prognostic for DM. In this study, characterization of a key component of this signature, miR-34c, revealed its role in chemotherapy resistance. METHODS: Two hundred forty-six NPC patient biopsy samples were subject to comprehensive miRNA profiling and immunohistochemistry (IHC). Two human normal nasopharyngeal cell lines (immortalized; NP69 and NP460), as well as the NPC cell line C666-1, were used for miR-34c gain-of-function and loss-of-function experiments. Signaling pathways were assessed using quantitative real-time PCR (qRT-PCR) and Western blot. Cell viability was measured using the ATPlite assay. RESULTS: MiR-34c was downregulated in NPC patient samples, and confirmed in vitro to directly target SOX4, a master regulator of epithelial-to-mesenchymal transition (EMT). MiR-34c downregulation triggered EMT-representative changes in NP69 and NP460 whereby Snail, ZEB1, CDH2, and SOX2 were upregulated, while Claudin-1 and CDH1 were downregulated. Phenotypically, inhibition of miR-34c led to cisplatin resistance, whereas miR-34c over-expression sensitized NPC cells to cisplatin. TGFß1 decreased miR-34c and increased SOX4 expression in vitro. The TGFß receptor 1 inhibitor SB431542 reduced SOX4 expression and increased cisplatin sensitivity. Finally, IHC revealed that lower SOX4 expression was associated with improved overall survival in chemotherapy-treated NPC patients. CONCLUSION: miR-34c is downregulated in NPC. Repression of miR-34c was shown to increase SOX4 expression, which leads to cisplatin resistance, while TGFß1 was found to repress miR-34c expression. Taken together, our study demonstrates that inhibition of the TGFß1 pathway could be a strategy to restore cisplatin sensitivity in NPC.

[Abnormal expression of Wnt3a and inhibiting role of its molecular-targeted intervening in hepatocellular carcinoma].

Objective: To investigate the Wnt3a expression in tissues of HCC and its gene knockout on effects of HepG2 cell proliferation or xenograft tumor growth. Methods: Hepatic Wnt3a expressions in 87 HCC and their matched surrounding tissues were observed by tissue microarray and immunohistochemistry for analyzing its clinicopathological characteristics; Wnt3a-knockout HepG2 cell lines were established by Crispr/cas9-sgRNA system and genomic cleavage efficiency was verified at gene level by surveyor assay. The relative proteins were confirmed by Western blotting; Cell Counting Kit-8 assay was used to examine cell proliferation after knocking-out Wnt3a successfully, and the nude mice HepG2 cell xenograft tumors delete that the relationship between Wnt3a and HCC growth. Results: The positive Wnt3a with brown staining particles was mainly distributed in cytosol and membrane of hepatocytes. The incidence of hepatic Wnt3a expression in cancerous tissues (95.4%) was significantly higher (χ (2) = 47.754, P < 0.001) than that in their surrounding tissues (49.4%). The high Wnt3a expression was 70.1% in the HCC and only 14.9% in the surrounding tissues. High Wnt3a expression was associated with poorly-differentiated grade, liver cirrhosis, HBV infection, portal vein invasion, TNM stage and 5-year survival rate. After knocked-out by Crispr/cas9-sgRNA system successfully, Wnt3a expression was down-regulated significantly at gene or protein level. Key molecule ß-catenin in cytoplasma was obviously inhibited. HepG2 cell lines proliferation was suppressed in time-dependent manner. The nude mice HepG2 cell xenograft tumors confirmed that the knock-out of Wnt3a could significantly supressed HCC growth with slower speed (t = 6.418, P < 0.001), smaller volume(869.4 ± 222.5 mm(3) vs 355.0 ± 99.9 mm(3), t = 5.168, P < 0.001), and lighter weight (0.88 ± 0.20 g vs 0.35 ± 0.11 g, t = 5.628, P < 0.001)compared with the control group. Conclusion: Abnormal expression of Wnt3a could be expected as a promising target for HCC gene therapy.

Single cell RNA sequencing of human liver reveals distinct intrahepatic macrophage populations.

The liver is the largest solid organ in the body and is critical for metabolic and immune functions. However, little is known about the cells that make up the human liver and its immune microenvironment. Here we report a map of the cellular landscape of the human liver using single-cell RNA sequencing. We provide the transcriptional profiles of 8444 parenchymal and non-parenchymal cells obtained from the fractionation of fresh hepatic tissue from five human livers. Using gene expression patterns, flow cytometry, and immunohistochemical examinations, we identify 20 discrete cell populations of hepatocytes, endothelial cells, cholangiocytes, hepatic stellate cells, B cells, conventional and non-conventional T cells, NK-like cells, and distinct intrahepatic monocyte/macrophage populations. Together, our study presents a comprehensive view of the human liver at single-cell resolution that outlines the characteristics of resident cells in the liver, and in particular provides a map of the human hepatic immune microenvironment.

Epstein-Barr virus BZLF1 protein impairs accumulation of host DNA damage proteins at damage sites in response to DNA damage.

Epstein-Barr virus (EBV) infection is closely associated with several human malignancies including nasopharyngeal carcinoma (NPC). The EBV immediate-early protein BZLF1 is the key mediator that switches EBV infection from latent to lytic forms. The lytic form of EBV infection has been implicated in human carcinogenesis but its molecular mechanisms remain unclear. BZLF1 has been shown to be a binding partner of several DNA damage response (DDR) proteins. Its functions in host DDR remain unknown. Thus, we explore the effects of BZLF1 on cellular response to DNA damage in NPC cells. We found that expression of BZLF1 impaired the binding between RNF8 and MDC1 (mediator of DNA damage checkpoint 1), which in turn interfered with the localization of RNF8 and 53BP1 to the DNA damage sites. The RNF8-53BP1 pathway is important for repair of DNA double-strand breaks and DNA damage-induced G2/M checkpoint activation. Our results showed that, by impairing DNA damage repair as well as abrogating G2/M checkpoint, BZLF1 induced genomic instability and rendered cells more sensitive to ionizing radiation. Moreover, the blockage of 53BP1 and RNF8 foci formation was recapitulated in EBV-infected cells. Taken together, our study raises the possibility that, by causing mis-localization of important DDR proteins, BZLF1 may function as a link between lytic EBV infection and impaired DNA damage repair, thus contributing to the carcinogenesis of EBV-associated human epithelial malignancies.

Preclinical evaluation of the mTOR-PI3K inhibitor BEZ235 in nasopharyngeal cancer models.

The dual PI3K-mTOR inhibitor BEZ235 was evaluated in preclinical models of nasopharyngeal carcinoma (NPC). The IC50 value of BEZ235 for growth was in the nanomolar range in vitro, induce G1 cycle arrest and apoptosis, and inhibited AKT and mTOR signaling in most NPC cell lines. No synergistic effect was observed when BEZ235 was combined with chemotherapy. BEZ235 increased MAPK activation in vitro but not in vivo. A daily schedule was more effective than a weekly schedule on tumor growth and inhibition of downstream mTOR signaling in vivo. The activity of BEZ235 maybe independent of the PIK3CA amplification and mutation status.

Significance of MAD2 expression to mitotic checkpoint control in ovarian cancer cells.

Chromosome instability is a commonly observed feature in ovarian carcinoma. Mitotic checkpoint controls are thought to be essential for accurate chromosomal segregation, and MAD2 is a key component of this checkpoint. In this study, we investigated the competence of the mitotic checkpoint and its relationship to the expression of MAD2 protein in seven ovarian cancer cell lines. We found that a significant number (43%, three of seven cell lines) of the tested ovarian cancer cells failed to arrest in the G(2)-M phase of the cell cycle in response to microtubule disruption. This loss of mitotic checkpoint control was associated with reduced expression of the MAD2 protein. To additionally understand the significance of the MAD2 to mitotic checkpoint control, we established an inducible expression system in which MAD2 was induced by the addition of ponasterone A. Notably, the induced expression of MAD2 in two checkpoint-defective ovarian cancer cell lines led to the restoration of mitotic checkpoint response to spindle-disrupting agents. Taken together, our findings suggest that the steady-state amount of MAD2 inside cells may represent a molecular switch for mitotic checkpoint control. This provides a novel insight into the molecular basis of CIN in ovarian carcinoma and has implications for effective use of checkpoint-targeting drugs.