The validation and clinical significance of LPCAT1 down-regulation in acute myeloid leukemia

BACKGROUND

Overexpression of lysophosphatidylcholine acyltransferase 1 (LPCAT1) has been found in various solid cancers and is associated with disease progression, metastasis, and recurrence. However, the expression pattern of LPCAT1 in acute myeloid leukemia (AML) bone marrow remains unknown. The present study aimed to compare LPCAT1 expression differences in bone marrow samples from AML patients and healthy controls and assess the clinical relevance of LPCAT1 in AML.

METHODS AND RESULTS

LPCAT1 expression in bone marrow was significantly lower in AML than in healthy controls predicted by public databases. Furthermore, real-time quantitative PCR (RQ-PCR) validated that LPCAT1 expression in bone marrow was significantly down-regulated in AML compared to healthy controls [0.056 (0.000-0.846) vs 0.253 (0.031-1.000)]. The DiseaseMeth version 2.0 and The Cancer Genome Atlas analysis revealed that the LPCAT1 promoter was hypermethylated in AML, and there was a strong negative correlation between LPCAT1 expression and methylation (R = - 0.610, P < 0.001). RQ-PCR revealed that the frequency of LPCAT1 low expression was lower in the FAB-M4/M5 subtype than in the other subtypes (P = 0.018). The ROC curve revealed that LPCAT1 expression could serve as a potential diagnostic marker for differentiating AML from controls with an area under the ROC curve of 0.819 (95% CI 0.743-0.894, P < 0.001). In cytogenetically normal AML, patients with LPCAT1 low expression had significantly longer overall survival than those without LPCAT1 low expression (median 19 versus 5.5 months, P = 0.036).

CONCLUSIONS

LPCAT1 is down-regulated in AML bone marrow, and LPCAT1 down-regulation could be used as a potential biomarker for AML diagnosis and prognosis.

Exosomes derived from human umbilical cord mesenchymal stem cells protect against papain-induced emphysema by preventing apoptosis through activating VEGF-VEGFR2-mediated AKT and MEK/ERK pathways in rats

Introduction

Chronic obstructive pulmonary disease (COPD) is a leading cause of high mortality and heavy burden in the world. Unfortunately, emphysema, as an important component of COPD, has no curative treatments currently. Recently, human umbilical cord mesenchymal stem cells-derived exosomes (hUCMSC-Ex) constitute a promising alternative approach for tissue regeneration and repair. However, the roles of hUCMSC-Ex in emphysema and its mechanism are largely unknown. Here, we investigated the effect and the action mechanism of hUCMSC-Ex in repairing emphysema induced by papain in rats.

Methods

SD rats were used to establish a papain-induced emphysema model and estimate the effect and mechanism of hUCMSC-Ex treatment. H&E staining and mean linear intercept (MLI) were used to evaluate the hUCMSC-Ex effect on emphysema. Western blotting, TUNEL and miRNA-seq were used to investigate the molecular mechanisms of hUCMSC-Ex treatment in models of papain-induced emphysema.

Results

Papain treatment led to typical emphysema, while hUCMSC-Ex reversed emphysematous changes effectively. Apoptosis of endothelial cells and other types of cells were observed in models, while hUCMSC-Ex effectively prevented their apoptosis. hUCMSC-Ex repressed active caspase-3, activated VEGF-VEGFR2-mediated AKT pathway and MEK/ERK pathway in emphysematous lungs. Notably, several miRNAs, such as hsa-miR-10a-5p and hsa-miR-146a-5p, were target related to the roles of hUCMSC-Ex in papain-induced emphysema through VEGF-VEGFR2-mediated AKT and MEK/ERK pathways.

Conclusions

hUCMSC-Ex effectively rescued the papain-induced emphysema injury through VEGF-VEGFR2-mediated AKT pathway and MEK/ERK pathway.

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Exosomes from human umbilical cord mesenchymal stem cells (hUCMSC-Ex) pro protect against papain-injured emphysema in rats.

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hUCMSC-Ex prevent lung cells apoptosis by activating VEGF-VEGFR2-mediated AKT and MEK/ERK pathways.

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Several miRNAs, such as hsa-miR-10a-5p, were target related to the roles of hUCMSC-Ex.

MiR-200c regulates invasion, proliferation and EMT of anaplastic thyroid cancer cells by targeting parathyroid hormone like hormone

This study aimed to explore the specific effect of miR-200c in anaplastic thyroid cancer (ATC). Hth74 and ARO cell lines were used. Proliferation, invasion, and colony formation activities of Hth74 and ARO cell lines affected by miR-200c were studied. Expression of epithelial-to-mesenchymal transition (EMT) markers (E-cadherin, N-cadherin, Slug, and Snail) in the Hth74 and ARO cell lines were validated by western blot and qRT-PCR. In addition, the regulation of the parathyroid hormone-like hormone (PTHLH) by miR-200c was assessed. Overexpression of miR-200c inhibited the invasion, proliferation, and colony formation of the ATC cell lines, whereas its downregulation achieved the opposite results. PTHLH was found to be regulated negatively by miR-200c through a miR-200c binding site within the 3'-UTR of PTHLH. miR-200c repressed the proliferation, invasion, and EMT process of cells in ATC cell lines by targeting PTHLH post-transcriptionally, which indicates that miR-200c may be a potential target for the treatment of ATC.

MiR-7-5pand miR-451 as diagnostic biomarkers for papillary thyroid carcinoma in formalin-fixed paraffin-embedded tissues

MiR-7-5p and miR-451 are important members of the small RNA family, which have been shown to be significantly downregulated in various human tumors and play a key role in the occurrence and development of tumors. However, little is known about their role in endocrine malignancies. This study aimed to investigate the diagnostic value of miR-7-5p and miR-451 levels in formalin-fixed paraffin-embedded tissues of papillary thyroid carcinoma (PTC) patients, as well as the relationship between clinicopathological characteristics and the two miRNAs. Quantitative real-time PCR (qRT-PCR) was performed to detect the expression levels of miR-7-5p and miR-451 in 101 PTC tissues and in 40 nodular goiter tissues (controls). MiR-7-5p and miR-451 levels were significantly downregulated in PTC patients compared with controls (P < 0.001). MiR-7-5p expression was further downregulated in tumors with larger diameter and advanced tumor stages (all P < 0.05). Moreover, the two miRNAs showed great capability of discriminating PTC patients from controls with 89.5% (miR-7-5p) and 76.8% (miR-451) diagnostic accuracy. Furthermore, according to univariable/multivariate logistic regression, miR-7-5p was significantly associated with PTC (P < 0.001). In conclusion, MiR-7-5p and miR-451 may be used as potential diagnostic biomarkers for identification and validation of PTC patients. Moreover, miR-7-5p appears to be associated with the aggressiveness of PTC.

Gastrointestinal disturbance and effect of fecal microbiota transplantation in discharged COVID-19 patients

BACKGROUND

To investigate the potential beneficial effect of fecal microbiota transplantation (FMT) on gastrointestinal symptoms, gut dysbiosis and immune status in discharged COVID-19 patients.

CASE PRESENTATION

A total of 11 COVID-19 patients were recruited in April, 2020, about one month on average after they were discharged from the hospital. All subjects received FMT for 4 consecutive days by oral capsule administrations with 10 capsules for each day. In total, 5 out of 11 patients reported to be suffered from gastrointestinal symptoms, which were improved after FMT. After FMT, alterations of B cells were observed, which was characterized as decreased naive B cell (P = 0.012) and increased memory B cells (P = 0.001) and non-switched B cells (P = 0.012).The microbial community richness indicated by operational taxonomic units number, observed species and Chao1 estimator was marginally increased after FMT. Gut microbiome composition of discharged COVID-19 patients differed from that of the general population at both phylum and genera level, which was characterized with a lower proportion of Firmicutes (41.0%) and Actinobacteria (4.0%), higher proportion of Bacteroidetes (42.9%) and Proteobacteria (9.2%). FMT can partially restore the gut dysbiosis by increasing the relative abundance of Actinobacteria (15.0%) and reducing Proteobacteria (2.8%) at the phylum level. At the genera level, Bifidobacterium and Faecalibacterium had significantly increased after FMT.

CONCLUSIONS

After FMT, altered peripheral lymphocyte subset, restored gut microbiota and alleviated gastrointestinal disorders were observe, suggesting that FMT may serve as a potential therapeutic and rehabilitative intervention for the COVID-19.

miR-21 facilitates the diagnostic value of miR-138 for papillary thyroid cancer in formalin-fixed paraffin-embedded tissues

Background

miR-138 was thought to be anti-tumor miRNA for its ability of suppressing tumor growth. The objective of this study was to evaluate the potential predictive value of miR-138 and its combination with miR-21 in formalin-fixed paraffin-embedded (FFPE) tissues of papillary thyroid cancers (PTCs).

Methods

miR-138/miR-21 expression was tested in 101 PTC and 51 benign thyroid nodule (control) patients using quantitative real-time PCR. Clinical and pathological characteristics of enrolled subjects were obtained from medical records.

Results

miR-138 was significantly down-regulated in PTC compared with controls (median 0.0122 vs. 0.0943), and miR-138 exhibited capability of discriminating PTC from controls, with a diagnostic accuracy of 71.1% (sensitivity 84.3%, specificity 49.5%). A combination of miR-138 and miR-21 increased the diagnostic accuracy to 79.1% (sensitivity 73.3%, specificity 76.5%). Multivariate logistic regression confirmed the association between miR-138/miR-21 expression and PTC diagnosis. Moreover, miR-138 expression was further down-regulated in PTC with capsule invasion compared with PTC tissues without capsule invasion (median 0.0043 vs. 0.0373, P=0.003).

Conclusions

MiR-138 expression was not only associated with onset of PTC, but also the aggressiveness of PTC. A combination of miR-138 and miR-21 enhanced the diagnostic value of individual biomarkers.

MiR-378 promoted cell proliferation and inhibited apoptosis by enhanced stem cell properties in chronic myeloid leukemia K562 cells

Dysregulation of miR-378 has been found in diverse types of tumors as well as in leukemia. The role of miR-378 in chronic myeloid leukemia (CML) remains unclear. The aim of the study was to reveal the potential effects of miR-378 in the pathological process and progress in CML. Our results showed general level of miR-378 was significant higher in CML patients compared to controls. Overexpression of miR-378 dramatically promoted cell proliferation and drug-resistance. Additionally, apoptosis was inhibited in cells transfected with miR-378. More and bigger stem cell sphere formation was observed in miR-378 transfected cells. Furthermore, enhanced expression of miR-378 was associated with upregulation of stem-cell makers OCT4 and c-Myc. Further study validated that miR-378 inhibited the expression of FUS1. Our research demonstrated the oncogenic nature of miR-378 in CML, and might contribute to the progress of CML.

Efficacy and Safety of Lenalidomide for Treatment of Low-/Intermediate-1-Risk Myelodysplastic Syndromes with or without 5q Deletion: A Systematic Review and Meta-Analysis

Background

Lenalidomide could effectively induce red blood cell (RBC) transfusion independence (TI) in patients with lower-risk (Low/Intermediate-1) myelodysplastic syndrome (MDS) with or without 5q deletion. However whether lenalidomide ultimately improves the overall survival (OS) of lower-risk MDS patients and reduces the progression to AML remains controversial.

Method

A meta-analysis was conducted to examine the efficacy and safety of lenalidomide in the treatment of lower-risk MDS. Efficacy was assessed according to erythroid hematologic response (HI-E), cytogenetic response (CyR), OS and AML progression. Safety was evaluated based on the occurrence rates of grades 3–4 adverse events (AEs).

Results

Seventeen studies were included consisting of a total of 2160 patients. The analysis indicated that the overall rate of HI-E was 58% with 95% confidence interval (CI) of 43–74%. The pooled estimates for the rates of CyR, complete CyR, and partial CyR were 44% (95% CI 19–68%), 21% (95% CI 13–30%) and 23% (95% CI 15–32%), respectively. The patients with 5q deletion had significantly higher rate of HI-E and CyR than those without 5q deletion (P = 0.002 and 0.001, respectively). The incidences of grades 3–4 neutropenia, thrombocytopenia, leukopenia, anemia, deep vein thrombosis, diarrhea, fatigue and rash were 51% (95% CI 30–73%), 31% (95% CI 20–42%), 9% (95% CI 5–13%), 7% (95% CI 2–12%), 3% (95% CI 2–5%), 3% (95% CI 1–5%), 2% (95% CI 1–4%) and 2% (95% CI 1–3%), respectively. Lenalidomide significantly improved OS (HR: 0.62, 95% CI 0.47–0.83, P = 0.001) and lowered the risk of AML progression in del(5q) patients (RR: 0.61, 95% CI 0.41–0.91, P = 0.014).

Conclusions

In spite of the AEs, lenalidomide could be effectively and safely used for the treatment of lower-risk MDS patients with or without 5q deletion.

Down-Regulation of miR-186 Correlates with Poor Survival in de novo Acute Myeloid Leukemia

BACKGROUND

MicroRNA-186 (miR-186) plays an important role in the pathogenesis of several cancers. Our study was intended to investigate the expression status and the prognostic implication of miR-186 in acute myeloid leukemia (AML).

METHODS

Real-time quantitative PCR was carried out in 112 de novo AML patients and 28 controls.

RESULTS

The level of miR-186 expression in AML was significantly down-regulated compared to normal controls (p < 0.001). Patients with low miR-186 expression presented significantly older age than those with high miR-186 expression (p = 0.004). MiR-186high patients had a significantly higher frequency of CEBPA mutation than miR-186low patients (20% and 4%, respectively, p = 0.022). In addition, miR-186low patients had a significantly lower complete remission (CR) rate (30% vs. 53%, respectively, p = 0.028) than miR-186high patients. Moreover, miR-186low patients showed significantly shorter overall survival (OS) time than miR-186high patients in both whole AML and non-M3 patients (p = 0.023 and 0.026, respectively). Additionally, the adverse prognostic impact of miR-186 down-regulation was also shown in both whole AML and non-M3 patients without CEBPA mutation (p = 0.017 and 0.023, respectively).

CONCLUSIONS

Our study suggests that miR-186 down-regulation is a frequent event and predicts poor prognosis in de novo AML patients.

BP1 overexpression is associated with adverse prognosis in de novo acute myeloid leukemia

To investigate DLX4 isoforms expression and their clinical significance in acute myeloid leukemia (AML). DLX4 transcript variant 1 (BP1) expression was significantly up-regulated in AML patients compared with normal controls. However, DLX4 transcript variant 2 (DLX7) was significantly down-regulated in AML patients. Both in the overall AML and the non-M3 AML cohorts, those patients with high BP1 expression (BP1(high)) showed significantly lower rates of complete remission than those with low BP1 expression (BP1(low)). BP1(high) cases had significantly shorter overall survival than BP1(low) cases in the overall AML cohort, non-M3 AML, and cytogenetically normal AML (CN-AML). Multivariate analysis confirmed the independent prognostic value of BP1 expression among both the overall AML cohort and non-M3 AML as well as CN-AML patients. However, we did not observe the impact of DLX7 expression on prognosis in AML patients. Our study reveals that BP1 overexpression serves as an independent risk factor in de novo AML patients.

Detection of SRSF2-P95 mutation by high-resolution melting curve analysis and its effect on prognosis in myelodysplastic syndrome

Hotspot mutations of serine/arginine-rich splicing factor 2 (SRSF2) gene have been identified in a proportion of hematologic malignancies including myelodysplastic syndrome (MDS). The aim of the present study was to develop a new approach to screen SRSF2 mutation and analyze the clinical relevance of SRSF2 mutations in Chinese MDS. A protocol based on high-resolution melting analysis (HRMA) was established to screen SRSF2-P95 mutation in 108 MDS patients and was compared with Sanger sequencing. The clinical relevance of SRSF2 mutations was further evaluated. HRMA identified five (4.6%) cases with SRSF2 mutation, completely validated by Sanger sequencing without false positive or negative results. The sensitivities of HRMA and Sanger sequencing were 10% and 25% for the detection of SRSF2-P95H mutation, respectively, against the background of wild-type DNA. Patients with SRSF2 mutation had shorter overall survival time than those with wild-type SRSF2 in both the whole cohort of cases and those with normal karyotype (P = 0.069 and 0.023, respectively). Multivariate analysis confirmed SRSF2 mutation as an independent risk factor in both patient populations. We established a fast, high-throughput, and inexpensive HRMA-based method to screen SRSF2 mutation, which could be used in clinical diagnostic laboratories. SRSF2 mutations were significantly associated with mortality rate in the MDS affected Chinese.

MiR-378 promotes the migration of liver cancer cells by down-regulating Fus expression

BACKGROUND

miR-378 regulates osteoblast differentiation and participates in tumor cell self-renewal and chemo-resistance. However, the function of miR-378 in liver cancer cell migration has not been reported to date.

METHODS

miR-378 expression was examined using real-time quantitative PCR. HepG2 cell migration and liver cell invasion were examined using wound-healing and cell invasion assays. Additionally, HepG2 cell metastasis was analyzed in nude mice.

RESULTS

miR-378 over-expression enhances HepG2 cell proliferation, migration and liver cell invasion. Typical metastatic lesions were found in the livers of mice injected with miR-378-transfected cells, and high levels of the CMV promoter were detected in the nodules, indicating that miR-378 promoted the metastasis of the tumor cells to the liver. We also demonstrated that miR-378 down-regulated Fus expression.

CONCLUSIONS

Our results suggested that miR-378 enhanced cell migration and metastasis by down-regulating Fus expression.

Methylation of CTNNA1 promoter: frequent but not an adverse prognostic factor in acute myeloid leukemia

The reduced expression of CTNNA1 gene, a putative tumor suppressor gene, has been found in several cancers including acute myeloid leukemia (AML). CTNNA1 expression is regulated by methylation and histone deacetylation. However, the clinical significance of CTNNA1 methylation in AML is rarely known. The present study was aimed to investigate the methylation status of CTNNA1 promoter region using methylation-specific PCR (MSP) and its clinical relevance in Chinese AML patients. Patients with CTNNA1 hypermethylation had significantly lower level of CTNNA1 transcript than those without CTNNA1 hypermethylation (P=0.031). The relationship of CTNNA1 methylation with clinical parameters was evaluated. Aberrant hypermethylation of CTNNA1 gene was found in 23.9% (37/155) AML cases. The status of CTNNA1 methylation was not correlated with the mutations of seven genes (FLT3-ITD, NPM1, C-KIT, IDH1/IDH2, DNMT3A, N/K-RAS and C/EBPA). There was no significant difference in the rates of complete remission (CR) between patients with and without CTNNA1 methylation. Although the overall survival (OS) time of the CTNNA1-methylated AML was shorter than that of CTNNA1-unmethylated group (6 months vs 9 months), the difference was not statistically significant (P=0.681). Our data suggest that CTNNA1 methylation is a recurrent event but has no influence on prognosis in AML.

Expression level of miR-93 in formalin-fixed paraffin-embedded tissues of breast cancer patients

MiR-93 is thought to be an onco-miRNA for its capabilities of enhancing tumor growth. The objective of this study was to evaluate the potential predictive value of miR-93 expression in formalin-fixed paraffin-embedded (FFPE) tissues of breast cancer patients. The expression of miR-93 was examined in 101 breast cancer patients and 40 controls using real-time quantitative PCR. We found that miR-93 was markedly upregulated in breast cancer patients compared with controls (p<0.01). The expression level of miR-93 was significantly correlated with miR-24/378 in breast cancer patients. MiR-93 exhibited great capability of discriminating between cancer patients and cancer-free controls by receiver-operator characteristic (ROC) curve analysis. MiR-93 showed 0.866 AUC (the area under the ROC curve) values. The MiR-93 level was found significantly correlated with breast cancer by univariable logistic regression. These results suggest that overexpression of miR-93 in FFPE tissues may serve as an indispensable source for biomarker discovery and validation in breast cancer patients.

Dysregulation of miR-124-1 predicts favorable prognosis in acute myeloid leukemia

OBJECTIVE

MicroRNA miR-124 has been suggested as a tumor suppressor for its role in inhibiting cell growth, inducing differentiation and promoting apoptosis. The present study was aimed to investigate the expression status of miR-124-1 and its clinical relevance in patients with acute myeloid leukemia (AML).

DESIGNS AND METHODS

Real-time quantitative PCR was performed to detect the expression level of miR-124-1 in AML patients. The clinical significance of miR-124-1 expression in AML was investigated.

RESULTS

miR-124-1 underexpression was identified in 30 (36%) of 83 AML patients. No significant difference could be observed in sex, age and blood parameters between the patients with and without miR-124-1 underexpression. The frequency of miR-124-1 underexpression was higher in the patients with t(15;17) than in others (62% versus 30%, P = 0.040). The status of miR-124-1 expression was not correlated with the mutations of nine genes (FLT3-ITD, NPM1, C-KIT, IDH1/IDH2, DNMT3A, N/K-RAS and C/EBPA). The patients with miR-124-1 underexpression had borderline longer overall survival and relapse-free survival than those without miR-124-1 underexpression (P = 0.052 and 0.045, respectively).

CONCLUSIONS

These findings suggest that miR-124-1 underexpression is a common event and might have a favorable impact on prognosis in AML.

Specificity of miR-378a-5p targeting rodent fibronectin

One criterion for microRNA identification is based on their conservation across species, and prediction of miRNA targets by empirical approaches using computational analysis relies on the presence of conservative mRNA 3'UTR. Because most miRNA target sites identified are highly conserved across different species, it is not clear whether miRNA targeting is species-specific. To predict miRNA targeting, we aligned all available fibronectin 3'UTRs and observed significant conservation of all 20 species. Twelve miRNAs were predicted to target most fibronectin 3'UTRs, but rodent fibronectin showed potential binding sites specific for five different miRNAs. One of them, the miR-378a-5p, contained a complete matching seed-region for all rodent fibronectin, which could not be found in any other species. We designed experiments to test whether the species-specific targeting possessed biological function and found that expression of miR-378a-5p decreased cancer cell proliferation, migration, and invasion, resulting in inhibition of tumor growth. Silencing fibronectin expression produced similar effects as miR-378a-5p, while transfection with a construct targeting miR-378-5p produced opposite results. Tumor formation assay showed that enhanced expression of fibronectin in the stromal tissues as a background environment suppressed tumor growth, while increased fibronectin expression inside the tumor cells promoted tumor growth. This was likely due to the different signaling direction, either inside-out or outside-in signal. Our results demonstrated that species-specific targeting by miRNA could also exert functional effects. Thus, one layer of regulation has been added to the complex network of miRNA signaling.

miR-17 targets tissue inhibitor of metalloproteinase 1 and 2 to modulate cardiac matrix remodeling

We aimed to investigate the role of miR-17 in cardiac matrix remodeling following myocardial infarction (MI). Using real-time PCR, we quantified endogenous miR-17 in infarcted mouse hearts. Compared with related microRNAs, miR-17 was up-regulated most dramatically: 3.7-fold and 2.4-fold in the infarct region 3 and 7 d post-MI, respectively, and 2.4-fold in the border zone at d 3 compared to sham control (P<0.01). Chimeric luciferase reporter constructs were cloned for miR-17 target validation. miR-17 targeted the 3'-UTR of TIMP2 and the protein coding region of TIMP1. The miR-17 mimic decreased TIMP2 (P<0.01) and TIMP1 (P<0.05) protein expression compared with the scrambled control. Inhibition of endogenous miR-17 by in vivo antagomir delivery enhanced TIMP2 (P<0.01) and TIMP1 (P<0.05) protein expression compared to the mismatch group, decreased MMP9 activity (P<0.05), reduced infarct size as early as 7 d post-MI (P<0.05), and improved cardiac function (fractional shortening and fractional area contraction, P<0.05) at d 21 and 28 post-MI. Transgenic mice overexpressing miR-17 in the heart confirmed the deleterious role of miR-17 in matrix modulation. Our study suggests that miR-17 participates in the regulation of cardiac matrix remodeling and provides a novel therapeutic approach using miR-17 inhibitors to prevent remodeling and heart failure after MI.

Overexpression of miR-378 is frequent and may affect treatment outcomes in patients with acute myeloid leukemia

MicroRNA miR-378 plays important roles in tumorigenesis by enhancing cell survival, reducing apoptosis, promoting tumor growth, angiogenesis and promoting cell migration and invasion. Abnormal expression of miR-378 has been observed in various types of cancers. The aim of this study was to investigate the expression status of miR-378 and its clinical significance in patients with acute myeloid leukemia (AML) using real-time quantitative PCR. miR-378 overexpression was identified in 26 of 84 (31%) AML patients. The patients with miR-378 overexpression had lower hemoglobin level than those without miR-378 overexpression (66 versus 78 g/L, respectively, P=0.010). The frequency of miR-378 overexpression in FAB-M2 subtype was higher than other subtypes (44% versus 20%, P=0.032). Moreover, the frequency of miR-378 overexpression was higher in patients with t(8;21) than in others (64% versus 24%, P=0.012). The status of miR-378 expression was not correlated with the mutations of eight genes (FLT3-ITD, NPM1, C-KIT, IDH1/IDH2, DNMT3A, C/EBPA and U2AF1). The difference in relapse-free survival was observed between patients with and without miR-378 overexpression (P=0.049). These findings suggest that miR-378 up-regulation is a common event and might have an adverse impact on prognosis in AML.

Mature miR-17-5p and passenger miR-17-3p induce hepatocellular carcinoma by targeting PTEN, GalNT7 and vimentin in different signal pathways

To study the physiological role of a single microRNA (miRNA), we generated transgenic mice expressing the miRNA precursor miR-17 and found that the mature miR-17-5p and the passenger strand miR-17-3p were abundantly expressed. We showed that mature miR-17-5p and passenger strand miR-17-3p could synergistically induce the development of hepatocellular carcinoma. The mature miR-17-5p exerted this function by repressing the expression of PTEN. In contrast, the passenger strand miR-17-3p repressed expression of vimentin, an intermediate filament with the ability to modulate metabolism, and GalNT7, an enzyme that regulates metabolism of liver toxin galactosamine. Hepatocellular carcinoma cells, HepG2, transfected with miR-17 formed larger tumors with more blood vessels and less tumor cell death than mock-treated cells. Expression of miR-17 precursor modulated HepG2 proliferation, migration, survival, morphogenesis and colony formation and inhibited endothelial tube formation. Silencing of PTEN, vimentin or GalNT7 with their respective siRNAs enhanced proliferation and migration. Re-expressing these molecules reversed their roles in proliferation, migration and tumorigenesis. Further experiments indicated that these three molecules do not interact with each other, but appear to function in different signaling pathways. Our results demonstrated that a mature miRNA can function synergistically with its passenger strand leading to the same phenotype but by regulating different targets located in different signaling pathways. We anticipate that our assay will serve as a helpful model for studying miRNA regulation.

MicroRNA miR-24 enhances tumor invasion and metastasis by targeting PTPN9 and PTPRF to promote EGF signaling

MicroRNAs are known to play regulatory roles in gene expression associated with cancer development. We analyzed levels of the microRNA miR-24 in patients with breast carcinoma and found that miR-24 was higher in breast carcinoma samples than in benign breast tissues. We generated constructs expressing miR-24 and studied its functions using both in vitro and in vivo techniques. We found that the ectopic expression of miR-24 promoted breast cancer cell invasion and migration. In vivo experiments in mice indicated that the expression of miR-24 enhanced tumor growth, invasion into local tissues, metastasis to lung tissues and decreased overall mouse survival. In the miR-24-expressing cells and tumors, EGFR was highly phosphorylated, whereas expression of the phosphatases tyrosine-protein phosphatase non-receptor type 9 (PTPN9) and receptor-type tyrosine-protein phosphatase F (PTPRF) were repressed. We confirmed that miR-24 could directly target both PTPN9 and PTPRF. Consistent with this, we found that the levels of phosphorylated epidermal growth factor receptor (pEGFR) were higher whereas the levels of PTPN9 and PTPRF were lower in the patients with metastatic breast carcinoma. Ectopic expression of PTPN9 and PTPRF decreased pEGFR levels, cell invasion, migration and tumor metastasis. Furthermore, we found that MMP2, MMP11, pErk, and ADAM15 were upregulated, whereas TIMP2 was downregulated; all of which supported the roles of miR-24 in tumor invasion and metastasis. Our results suggest that miR-24 plays a key role in breast cancer invasion and metastasis. miR-24 could potentially be a target for cancer intervention.

SF3B1 mutation is a rare event in Chinese patients with acute and chronic myeloid leukemia

OBJECTIVE

Somatic mutations of SF3B1 gene have recently been identified in myelodysplastic syndrome and chronic lymphocytic leukemia. The frequency and clinical relevance of SF3B1 mutations have been rarely studied in acute myeloid leukemia (AML) and chronic myeloid leukemia (CML). The present study was aimed to analyze the frequency of SF3B1 mutations in AML and CML.

DESIGNS AND METHODS

High-resolution melting analysis (HRMA) was established to detect the mutation hotspots (codon E622, H662, K666, and K700) of SF3B1 gene in 275 AML and 81 CML patients.

RESULTS

Heterozygous SF3B1 mutations were detected in three AML patients by HRMA. Direct DNA sequencing identified one K666T, one K666N and one K700E mutations. All three AML patients had normal karyotypes. One case also had NPM1 and DNMT3A mutations, one had FLT3 internal tandem duplication and DNMT3A mutations, and the other had NPM1 mutation. No SF3B1 mutations were detected in CML patients.

CONCLUSIONS

SF3B1 mutation is a rare molecular event in Chinese AML and CML patients.

Versican 3'-untranslated region (3'-UTR) functions as a ceRNA in inducing the development of hepatocellular carcinoma by regulating miRNA activity

This study was designed to explore the role of versican in the development of hepatocellular carcinoma (HCC). Ectopic expression of the versican 3'-untranslated region (3'-UTR) was studied as a competitive endogenous RNA for regulating miRNA functions. We used this approach to modulate the expression of versican and its related proteins in 3'-UTR transgenic mice and in the liver cancer cell line HepG2, stably transfected with the 3'-UTR or a control vector. We demonstrated that transgenic mice expressing the versican 3'-UTR developed HCC and increased expression of versican isoforms V0 and V1. HepG2 cells transfected with versican 3'-UTR displayed increased proliferation, survival, migration, invasion, colony formation, and enhanced endothelial cell growth, but decreased apoptosis. We found that versican 3'-UTR could bind to miRNAs miR-133a, miR-199a*, miR-144, and miR-431 and also interacted with CD34 and fibronectin. As a consequence, expression of versican, CD34, and fibronectin was up-regulated by ectopic transfection of the versican 3'-UTR, which was confirmed in HepG2 cells and in transgenic mice as compared with wild-type controls. Transfection with siRNAs targeting the versican 3'-UTR abolished the effects of the 3'-UTR. Taken together, these results demonstrate that versican V0 and V1 isoforms play important roles in HCC development and that versican mRNAs compete with endogenous RNAs in regulating miRNA functions.

The intermediate filament vimentin mediates microRNA miR-378 function in cellular self-renewal by regulating the expression of the Sox2 transcription factor

MicroRNAs are short noncoding RNAs that are implicated in cell self- renewal and cancer development. We show that miR-378 is up-regulated in human cancers and found that tumor cells transfected with miR-378 acquired properties of tumor stem cells, including cell self-renewal. Overexpression of miR-378 enhanced cell survival and colony formation. Isolated from a single-cell colony, the miR-378-expressing cells formed tumors in nude mice at low cell densities. These cells expressed higher levels of miR-378 and formed more and larger spheres and colonies. We found that the miR-378-expressing cells contained a large number of side population cells and could undergo differentiation. Cells transfected with miR-378 expressed increased levels of Sox2. Expression of miR-378 and Sox2 was found correlated significantly in cancer cell lines and in cancer patient specimens. We also observed opposite levels of vimentin in the cancer cell lines and human breast carcinoma specimens. We further demonstrated that vimentin is a target of miR-378, and ectopic transfection of vimentin inhibited Sox2 expression, resulting in decreased cell survival. Silencing vimentin promoted Sox2 expression and cell survival. Our study demonstrates that miR-378 is a regulator of stem cell marker Sox2 by targeting vimentin, which may serve as a new tool in studying the role of stem cells in tumorigenesis.

Aberrant hypomethylation of SALL4 gene in patients with myelodysplastic syndrome

The abnormalities of SALL4 gene, which encodes a zinc-finger transcription factor and is essential for developmental events, have been found to be involved in tumorigenesis. In this study, we investigated the methylation status of the CpG island of SALL4 promoter region in myelodysplastic syndrome (MDS) using methylation-specific PCR (MSP). Aberrant hypomethylation of SALL4 gene was found in 21.7% (18/83) of the cases analyzed. A significantly positive correlation was identified between the level of SALL4 transcript and the status of SALL4 hypomethylation (R=0.641, P<0.001). No correlation was found between SALL4 hypomethylation and clinical parameters. However, the frequency of SALL4 hypomethylation significantly increased in higher risk MDS (14% in Low/Int-1 versus 39% in Int-2/High, P=0.031). The association between SALL4 hypomethylation and the mutations in three methylation modifiers (IDH1, IDH2 and DNMT3A) was not observed. Although the estimated 50% survival time of the SALL4-hypomethylated group was shorter than that of SALL4-methylated group (11.0 months vs. 20.0 months), the difference was not statistically significant (P=0.430). These findings suggest that hypomethylation of SALL4 promoter is a common event in MDS.

MiR-93 enhances angiogenesis and metastasis by targeting LATS2

Here we report that miR-93, a miRNA in the miR-106B~25 cluster, a paralog of the miR-17-92 cluster, was significantly upregulated in human breast carcinoma tissues. We stably expressed miR-93 in the MT-1 human breast carcinoma cell line and found that tumors formed by the miR-93 cells contained more blood vessels than those formed by the control cells. Co-culture experiments indicated that the MT-1 cells displayed a high activity of adhesion with endothelial cells and could form larger and more tube-like structures with endothelial cells. Lung metastasis assays were performed in a mouse metastatic model, and it was found that expression of miR-93 promoted tumor cell metastasis to lung tissue. In cell culture, expression of miR-93 enhanced cell survival and invasion. We examined the potential target that mediated miR-93's effects and found that the large tumor suppressor, homology 2 (LATS2) was a target of miR-93. Higher levels of LATS2 were associated with cell death in the tumor mass. Silencing LATS2 expression promoted cell survival, tube formation and invasion, while ectopic expression of LATS2 decreased cell survival and invasion. These findings demonstrated that miR-93 promoted tumor angiogenesis and metastasis by suppressing LATS2 expression. Our results suggest that the inhibition of miR-93 function may be a feasible approach to repress tumor metastasis.

U2AF1 mutations in Chinese patients with acute myeloid leukemia and myelodysplastic syndrome

Somatic mutations of U2AF1 gene have recently been identified in myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). In this study, we analyzed the frequency and clinical impact of U2AF1 mutations in a cohort of 452 Chinese patients with myeloid neoplasms. Mutations in U2AF1 were found in 2.5% (7/275) of AML and 6.3% (6/96) of MDS patients, but in none of 81 CML. All mutations were heterozygous missense mutations affecting codon S34 or Q157. There was no significant association of U2AF1 mutation with blood parameters, FAB subtypes, karyotypes and other gene mutations in AML. The overall survival (OS) of AML patients with U2AF1 mutation (median 3 months) was shorter than those without mutation (median 7 months) (P = 0.035). No difference in the OS was observed between MDS patients with and without U2AF1 mutations. Our data show that U2AF1 mutation is a recurrent event at a low frequency in AML and MDS.

MicroRNA miR-199a-3p regulates cell proliferation and survival by targeting caveolin-2

Recent advances in the study of microRNAs indicate that they have an important role in regulating cellular activities such as proliferation, morphogenesis, apoptosis and differentiation by regulating the expression of various genes. MiR-199a-3p is highly expressed in hair follicles and in some tumor cells, suggesting its participation in tumor progression, but it is significantly underexpressed in hepatocellular carcinoma and in bladder cancer. The mechanism underlying these effects is not yet known. Here, we dissect the effects of miR-199a-3p on YPEN-1 endothelial cells, and MDA-MB-231 and MT-1 breast cancer cell lines. We found that expression of miR-199a-3p promotes proliferation and survival of endothelial cells as well as breast cancer cells. Remarkably, miR-199a-3p inhibited both endogenous caveolin-2 activity and exogenous caveolin-2 activity, which was confirmed by a reporter construct bearing the 3'-untranslated region of caveolin-2. However, overexpression of caveolin-2 completely counteracted the enhancement of miR-199a-3p-mediated activities on cell proliferation, survival and sensitivity of tumor cells to anticancer drugs. Our findings suggest that MiR-199a-3p targeting of caveolin-2 might have an important role in breast cancer tumor progression, making it a potential candidate for intervention in cancer.

Versican G3 domain modulates breast cancer cell apoptosis: a mechanism for breast cancer cell response to chemotherapy and EGFR therapy

Overexpression of EGFR and versican has been reported in association with breast cancers. Considered oncogenic, these molecules may be attractive therapeutic targets. Possessing anti-apoptotic and drug resistant properties, overexpression of these molecules is accompanied by selective sensitization to the process of apoptosis. In this study, we exogenously expressed a versican G3 construct in breast cancer cell lines and analyzed the effects of G3 on cell viability in fetal bovine serum free conditioned media and evaluated the effects of apoptotic agent C2-ceramide, and chemotherapeutic agents including Docetaxel, Doxorubicin, and Epirubicin. Versican G3 domain enhanced tumor cell resistance to apoptosis when cultured in serum free medium, Doxorubicin, or Epirubicin by up-regulating pERK and GSK-3β (S9P). However, it could be prevented by selective EGFR inhibitor AG 1478 and selective MEK inhibitor PD 98059. Both AG 1478 and PD 98059 enhanced expression of pSAPK/JNK, while selective JNK inhibitor SP 600125 enhanced expression of GSK-3β (S9P). Versican G3 promoted cell apoptosis induced by C2-ceramide or Docetaxel by enhancing expression of pSAPK/JNK and decreasing expression of GSK-3β (S9P), an observation blocked by AG 1478 or SP 6000125. Inhibition of endogenous versican expression by siRNA or reduction of versican G3's expression by linking G3 with 3'UTR prevented G3 modulated cell apoptosis. The dual roles of G3 in modulating breast cancer cell resistance to chemotherapeutic agents may in part explain a potential mechanism for breast cancer cell resistance to chemotherapy and EGFR therapy. The apoptotic effects of chemotherapeutics depend upon the activation and balance of down stream signals in the EGFR pathway. GSK-3β (S9P) appears to function as a key checkpoint in this balance of apoptosis and anti-apoptosis. Investigation and potential consideration of targeting GSK-3β (S9P) merits further study.

A non-coding transcript of nephronectin promotes osteoblast differentiation by modulating microRNA functions

We investigated the roles of the non-coding transcripts and found that expression of a fragment containing the 3'-untranslated region (3'-UTR) of nephronectin in osteoblast progenitor cells MC3T3-E1 promoted cell differentiation dramatically. We hypothesized that the ectopically expressed 3'-UTR binds microRNAs and modulates their functions. β-Catenin and GSK3β were up-regulated in the 3'-UTR-transfected cells, contributing to the increased cell differentiation, through reduction of EGFR and ERK phosphorylation. Activator of GSK3β promoted differentiation, while inhibitor of GSK3β blocked differentiation. Our results indicate that the non-coding transcripts are important in regulating cell activities and may have potential application for modulating endogenous microRNA functions.

Expression of CD44 3'-untranslated region regulates endogenous microRNA functions in tumorigenesis and angiogenesis

The non-coding 3'-untranslated region (UTR) plays an important role in the regulation of microRNA (miRNA) functions, since it can bind and inactivate multiple miRNAs. Here, we show the 3'-UTR of CD44 is able to antagonize cytoplasmic miRNAs, and result in the increased translation of CD44 and downstream target mRNA, CDC42. A series of cell function assays in the human breast cancer cell line, MT-1, have shown that the CD44 3'-UTR inhibits proliferation, colony formation and tumor growth. Furthermore, it modulated endothelial cell activities, favored angiogenesis, induced tumor cell apoptosis and increased sensitivity to Docetaxel. These results are due to the interaction of the CD44 3'-UTR with multiple miRNAs. Computational algorithms have predicted three miRNAs, miR-216a, miR-330 and miR-608, can bind to both the CD44 and CDC42 3'-UTRs. This was confirmed with luciferase assays, western blotting and immunohistochemical staining and correlated with a series of siRNA assays. Thus, the non-coding CD44 3'-UTR serves as a competitor for miRNA binding and subsequently inactivates miRNA functions, by freeing the target mRNAs from being repressed.

Versican G3 promotes mouse mammary tumor cell growth, migration, and metastasis by influencing EGF receptor signaling

Increased versican expression in breast tumors is predictive of relapse and has negative impact on survival rates. The C-terminal G3 domain of versican influences local and systemic tumor invasiveness in pre-clinical murine models. However, the mechanism(s) by which G3 influences breast tumor growth and metastasis is not well characterized. Here we evaluated the expression of versican in mouse mammary tumor cell lines observing that 4T1 cells expressed highest levels while 66c14 cells expressed low levels. We exogenously expressed a G3 construct in 66c14 cells and analyzed its effects on cell proliferation, migration, cell cycle progression, and EGFR signaling. Experiments in a syngeneic orthotopic animal model demonstrated that G3 promoted tumor growth and systemic metastasis in vivo. Activation of pERK correlated with high levels of G3 expression. In vitro, G3 enhanced breast cancer cell proliferation and migration by up-regulating EGFR signaling, and enhanced cell motility through chemotactic mechanisms to bone stromal cells, which was prevented by inhibitor AG 1478. G3 expressing cells demonstrated increased CDK2 and GSK-3β (S9P) expression, which were related to cell growth. The activity of G3 on mouse mammary tumor cell growth, migration and its effect on spontaneous metastasis to bone in an orthotopic model was modulated by up-regulating the EGFR-mediated signaling pathway. Taken together, EGFR-signaling appears to be an important pathway in versican G3-mediated breast cancer tumor invasiveness and metastasis.

MicroRNA MiR-17 retards tissue growth and represses fibronectin expression

MicroRNAs (miRNAs) are single-stranded regulatory RNAs, frequently expressed as clusters. Previous studies have demonstrated that the six-miRNA cluster miR-17~92 has important roles in tissue development and cancers. However, the precise role of each miRNA in the cluster is unknown. Here we show that overexpression of miR-17 results in decreased cell adhesion, migration and proliferation. Transgenic mice overexpressing miR-17 showed overall growth retardation, smaller organs and greatly reduced haematopoietic cell lineages. We found that fibronectin and the fibronectin type-III domain containing 3A (FNDC3A) are two targets that have their expression repressed by miR-17, both in vitro and in transgenic mice. Several lines of evidence support the notion that miR-17 causes cellular defects through its repression of fibronectin expression. Our single miRNA expression assay may be evolved to allow the manipulation of individual miRNA functions in vitro and in vivo. We anticipate that this could serve as a model for studying gene regulation by miRNAs in the development of gene therapy.

A 3'-untranslated region (3'UTR) induces organ adhesion by regulating miR-199a* functions

Mature microRNAs (miRNAs) are single-stranded RNAs of 18–24 nucleotides that repress post-transcriptional gene expression. However, it is unknown whether the functions of mature miRNAs can be regulated. Here we report that expression of versican 3′UTR induces organ adhesion in transgenic mice by modulating miR-199a* activities. The study was initiated by the hypothesis that the non-coding 3′UTR plays a role in the regulation of miRNA function. Transgenic mice expressing a construct harboring the 3′UTR of versican exhibits the adhesion of organs. Computational analysis indicated that a large number of microRNAs could bind to this fragment potentially including miR-199a*. Expression of versican and fibronectin, two targets of miR-199a*, are up-regulated in transgenic mice, suggesting that the 3′UTR binds and modulates miR-199a* activities, freeing mRNAs of versican and fibronectin from being repressed by miR-199a*. Confirmation of the binding was performed by PCR using mature miR-199a* as a primer and the targeting was performed by luciferase assays. Enhanced adhesion by expression of the 3′UTR was confirmed by in vitro assays. Our results demonstrated that upon arrival in cytoplasm, miRNA activities can be modulated locally by the 3′UTR. Our assay may be developed as sophisticated approaches for studying the mutual regulation of miRNAs and mRNAs in vitro and in vivo. We anticipate that expression of the 3′UTR may be an approach in the development of gene therapy.

MicroRNA miR-328 regulates zonation morphogenesis by targeting CD44 expression

Morphogenesis is crucial to initiate physiological development and tumor invasion. Here we show that a microRNA controls zonation morphogenesis by targeting hyaluronan receptor CD44. We have developed a novel system to study microRNA functions by generating constructs expressing pre-miRNAs and mature miRNAs. Using this system, we have demonstrated that expression of miR-328 reduced cell adhesion, aggregation, and migration, and regulated formation of capillary structure. Protein analysis indicated that miR-328 repressed CD44 expression. Activities of luciferase constructs harboring the target site in CD44, but not the one containing mutation, were repressed by miR-328. Zonation morphogenesis appeared in cells transfected by miR-328: miR-328-transfected cells were present on the surface of zonating structures while the control cells stayed in the middle. MiR-328-mediated CD44 actions was validated by anti-CD44 antibody, hyaluronidase, CD44 siRNA, and CD44 expression constructs. In vivo experiments showed that CD44-silencing cells appeared as layers on the surfaces of nodules or zonating structures. Immuno-histochemistry also exhibited CD44-negative cells on the surface layers of normal rat livers and the internal zones of Portal veins. Our results demonstrate that miR-328 targets CD44, which is essential in regulating zonation morphogenesis: silencing of CD44 expression is essential in sealing the zonation structures to facilitate their extension and to inhibit complex expansion.

The ability of versican to simultaneously cause apoptotic resistance and sensitivity

Expression of the extracellular matrix proteoglycan versican is associated with more than 10 types of cancers, often being secreted by stromal cells in response to tumor signals. Previous work in our lab has shown that overexpression of the V1 versican isoform in cultured fibroblasts (V1 cells) increases both proliferation and apoptotic resistance. We show here that V1 cells induced tumor formation in nude mice and that, in keeping with previously shown apoptotic resistance, V1 cells have down-regulated Fas mRNA and protein levels. Unexpectedly, however, V1 cells were found to be sensitized to a wide range of cytotoxic agents. This combination of selective apoptotic resistance and sensitivity is often seen in cancer cells. V1 cells were also shown to have high resting levels of p53 and murine double minute-2 proteins, correlating with apoptotic sensitivity. Treatment with UV radiation induced p21 expression in vector-transfected cells but not in V1 cells. As p21 induces cell cycle arrest and inhibits apoptosis, its loss in V1 cells, coupled with high resting levels of proapoptotic p53, may be at least partially involved in their premature death following cytotoxic treatment. This study further supports the importance of versican in cancer cell biology and the complexity of apoptosis regulation.

Versican mediates mesenchymal-epithelial transition

Versican is a large extracellular chondroitin sulfate proteoglycan that belongs to the family of lecticans. Alternative splicing of versican generates at least four isoforms named V0, V1, V2, and V3. We show here that ectopic expression of versican V1 isoform induced mesenchymal-epithelial transition (MET) in NIH3T3 fibroblasts, and inhibition of endogenous versican expression abolished the MET in metanephric mesenchyme. MET in NIH3T3 cells was demonstrated by morphological changes and dramatic alterations in both membrane and cytoskeleton architecture. Molecular analysis showed that V1 promoted a "switch" in cadherin expression from N- to E-cadherin, resulting in epithelial specific adhesion junctions. V1 expression reduced vimentin levels and induced expression of occludin, an epithelial-specific marker, resulting in polarization of V1-transfected cells. Furthermore, an MSP (methylation-specific PCR) assay showed that N-cadherin expression was suppressed through methylation of its DNA promoter. Exogenous expression of N-cadherin in V1-transfected cells reversed V1's effect on cell aggregation. Reduction of E-cadherin expression by Snail transfection and siRNA targeting E-cadherin abolished V1-induced morphological alteration. Transfection of an siRNA construct targeting versican also reversed the changed morphology induced by V1 expression. Silencing of endogenous versican prevented MET of metanephric mesenchyme. Taken together, our results demonstrate the involvement of versican in MET: expression of versican is sufficient to induce MET in NIH3T3 fibroblasts and reduction of versican expression decreased MET in metanephric mesenchyme.

Versican G3 domain promotes blood coagulation through suppressing the activity of tissue factor pathway inhibitor-1

We have detected versican, a member of the large chondroitin sulfate proteoglycans, and its degraded C-terminal G3 fragments in human plasma and observed that the versican G3 domain promoted blood coagulation. Silencing G3 expression with small interfering RNA reduced the effect of G3 on coagulation. Plasma coagulation assays suggest that G3 enhances coagulation irrespective of its actions on platelets and white blood cells. To examine how versican affected blood coagulation, we used normal human plasma and different types of coagulation factor-deficient plasmas. The experiments indicated that versican enhanced coagulation through the extrinsic pathway, and that Factor VII was the target molecule. FVII activity assays showed that G3 activated FVII in the presence of plasma but not with purified FVII directly. Yeast two-hybrid, immunoprecipitation, and gel co-migration assays showed that G3 interacted with the tissue factor pathway inhibitor-1 (TFPI-1). TFPI-1 activity assays suggested that G3 inhibited TFPI-1 activity, allowing FVIIa and FXa to facilitate the coagulation process. G3-induced blood coagulation was further confirmed with a mouse model in a real-time manner. Taken together, these results indicate that versican may represent a new target for the development of therapies against atherosclerosis.