Transcriptional profiles of peripheral blood leukocytes identify patients with cholangiocarcinoma and predict outcome

Silencing of MicroRNA-503 in Rat Mesenchymal Stem Cells Exerts Potent Antitumorigenic Effects in Lung Cancer Cells

Purpose

Mesenchymal stem cells (MSCs) are largely studied for their potential clinical use. Recently, there has been gained further interest in the relationship between MSCs and tumorigenesis. MSCs are reported to both promote and abrogate tumor growth. The present study was designed to investigate whether miRNAs are involved in the interactions between MSCs and tumor cells in the tumor microenvironment.

Materials and Methods

Rat bone marrow-derived MSCs (rMSCs) were cultured with or without tumor-conditioned medium (TCM) to observe the effect upon MSCs by TCM. Microarrays and real-time PCR were performed between the two groups. A series of experiments were used to reveal the functional significance of microRNA-503 (miR-503) in rMSCs. Furthermore, the antitumorigenic effect of silencing of miR-503 in rMSCs (miR-503-i-rMSCs) in vivo was measured.

Results

We found that rMSCs in vitro exhibited tumor-promoting properties in TCM, and the microRNA profiles of rMSCs were significantly altered in TCM. However, miR-503-i-rMSCs can decrease the angiogenesis and growth of A549 cells. We also demonstrated in an in vivo tumor model that miR-503-i-rMSCs inhibited A549 tumor angiogenesis and significantly abrogated tumor initiation and growth. CD133 assays in peripheral blood and A549 xenografts further validated that miR-503-i-rMSCs, rather than rMSCs, exerted an antitumorigenic action in the A549 tumor model.

Conclusion

Our results suggest that miR-503-i-rMSCs are capable of tumor suppression. Further studies are required to develop clinical therapies based on the inhibition of the tumor-promoting properties and potentiation of the anti-tumor properties of MSCs.

Relationship between polymorphisms of CXCL3 gene and preeclampsia

Background: Preeclampsia (PE), a pregnancy-specific disease, is a main cause of maternal and perinatal mortality in the world, the exact pathogenesis of which is still unknown. Recent studies have found it is a disorder caused by multiple factors and genes. Previously, we found a significantly abnormal expression of CXCL3 in plasma and placenta of severe preeclampsia. Here, we intend to explore the association of polymorphisms in CXCL3 gene with preeclampsia susceptibility in women from western China.Methods: Four hundred eighty-one pregnant women were involved in this case-control study, including 83 early-onset severe preeclampsia cases, 114 late-onset severe preeclampsia cases, 41 mild preeclampsia cases and 243 normal pregnancies. The rs370655 variant in CXCL3 was detected by the method of polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).Results: No significantly reduced risk of preeclampsia is observed in the rs370655 AA genotype compared with other genotypes (AG versus AA: OR = .82, 95%CI = .54-1.26; GG versus AA: OR = .95, 95%CI = .56-1.61). After subgroup analysis, there are still no significant differences among various genotypes in the mild preeclampsia, early-onset severe preeclampsia and late-onset sever preeclampsia.Conclusion: Our study suggests that rs370655 polymorphism in CXCL3 gene may be not the risk factor of preeclampsia, exploring other consequential SNPs in CXCL3 gene may help to predict the preeclampsia.

Prognostic biomarkers for cholangiocarcinoma and their clinical implications

Cholangiocarcinoma (CCA) is a poorly prognostic cancer with limited treatment options. Most patients have unresectable tumors when they are diagnosed and the chemotherapies provided are of limited benefit. Prognostic markers are therefore necessary to predict the disease outcome, risk of relapse, or to suggest the best treatment option. Areas covered: This article provides an up-to-date review of biomarkers with promising characteristics to be prognostic markers for CCA reported in the past 5 years. The biomarkers are sub-classified into tissue and serum markers. Proteins, RNAs, peripheral blood cells etc., that are associated with aggressive phenotypes, signal pathways, chemo-drug resistance, and those that reflect the survival time of CCA patients are evaluated for their prognostic prediction values. Expert commentary: CCAs are heterogeneous tumors of different histo-pathological subtypes and genetic influences and, therefore, potential markers should be validated in larger collectives with varied epidemiological backgrounds. A systematic review and meta-analysis should be done to clarify the impact of the reported biomolecules for their potential prognostic values. Non- or low-invasive sample collections, as well as the simple and affordable determination methods, should be constructed to make the prognostic biomarkers available in clinical practice.

Effects of CXCL3 on migration, invasion, proliferation and tube formation of trophoblast cells

CXCL3 was reportedly associated with the invasion and metastasis of various malignancies, the role of CXCL3, however, in preeclampsia has not been fully discussed. We previously found placental CXCL3 level in severe preeclampsia was significantly lower than that in healthy pregnancy and exogenous recombinant human CXCL3 protein was able to promote trophoblasts' migration and proliferation. The current study, therefore, is further to investigate effects of endogenous CXCL3 on migration, invasion, proliferation, tube formation and apoptosis of trophoblasts. Immunofluorescence staining demonstrated that CXCL3 localized in both trophoblasts of placenta and HTR-8/SVneo cells. Moreover, data showed that migration, invasion, proliferation and tube-formation capability of HTR-8/SVneo cells transfected with siRNA-CXCL3 were suppressed by down-regulation of CXCL3, while those behaviors of HTR-8/SVneo cells transfected with pEZ-CXCL3 were enhanced by upregulation of CXCL3. Nevertheless, the apoptosis of HTR-8/SVneo cells was not affected by neither siRNA nor overexpression plasmid. The result suggests that CXCL3 is involved in migration, invasion, proliferation and tubule formation of trophoblasts and may play a key role in the pathogenesis of preeclampsia.

The microRNA-15a-PAI-2 axis in cholangiocarcinoma-associated fibroblasts promotes migration of cancer cells

BACKGROUND

Cholangiocarcinoma (CCA) has an abundance of tumor stroma which plays an important role in cancer progression via tumor-promoting signals. This study aims to explore the microRNA (miRNA) profile of CCA-associated fibroblasts (CCFs) and the roles of any identified miRNAs in CCA progression.

METHODS

miRNA expression profiles of CCFs and normal skin fibroblasts were compared by microarray. Identified downregulated miRNAs and their target genes were confirmed by real-time PCR. Their binding was confirmed by a luciferase reporter assay. The effects of conditioned-media (CM) of miRNA mimic- and antagonist-transfected CCFs were tested in CCA migration in wound healing assays. Finally, the levels of miRNA and their target genes were examined by real-time PCR and immunohistochemistry in clinical CCA samples.

RESULTS

miR-15a was identified as a downregulated miRNA in CCFs. Moreover, PAI-2 was identified as a novel target gene of miR-15a. Recombinant PAI-2 promoted migration of CCA cells. Moreover, CM from miR-15a mimic-transfected CCFs suppressed migration of CCA cells. Lower expression of miR-15a and higher expression of PAI-2 were observed in human CCA samples compared with normal liver tissues. Importantly, PAI-2 expression correlated with poor prognosis in CCA patients.

CONCLUSIONS

These findings highlight the miR-15a/PAI-2 axis as a potential therapeutic target in CCA patients.

Cholangiocyte senescence caused by lysophosphatidylcholine as a potential implication in carcinogenesis

BACKGROUND

The incidence of biliary tract cancer in patients with pancreaticobiliary maljunction or intrahepatic cholelithiasis is markedly high with undefined mechanism. In these diseases, biliary lysophosphatidylcholine (LPC) level is reportedly increased. This study investigated the influence of LPC on cholangiocytes focusing on cellular senescence and its potential contribution to carcinogenesis.

METHODS

Cultured MMNK-1, an immortalized human cholangiocyte was treated with LPC in vitro and its effect was evaluated.

RESULTS

Lysophosphatidylcholine demonstrated cytotoxicity with generation of intracellular reactive oxygen species. Accordingly, LPC provoked oxidative DNA injury, whereas the gene expressions of DNA repair enzyme (OGG1, MUTYH, MTH1) remained unchanged. Interestingly, LPC caused global DNA hypomethylation, which is frequently observed in cancer tissues. Microarray analysis identified differentially regulated genes in response to LPC, which included the components of senescence-associated secretory phenotype (SASP) including interleukin-8 (IL-8), IL-6, transforming growth factor-β and plasminogen activator inhibitor-1. Significant induction of these genes was further confirmed by quantitative real-time polymerase chain reaction. In addition to upregulation of p21 gene expression, senescence-associated beta-galactosidase activity, a widely used marker of cellular senescence was significantly induced by the treatment of LPC.

CONCLUSIONS

Based on these data, cholangiocyte senescence and SASP caused by LPC are potential pathogenic mechanisms in the development of biliary tract cancer.