Identification of CpG Sites of SERPINA5 Promoter with Opposite Methylation Patterns in Benign and Malignant Prostate Cells

Therapeutic exosomes loaded with SERPINA5 attenuated endometrial cancer cell migration via the integrin β1/FAK signaling pathway

BACKGROUND

Metastasis is still the major cause of endometrial cancer (EC)-related death. Because of their biological function and regenerative properties, exosomes have been applied to therapeutic regimens. SERPINA5 expression is downregulated in several tumors and linked to tumor cell migration and invasion. However, the expression and biological functions of SERPINA5 in EC remain unclear.

METHODS

The levels of SERPINA5 in plasma exosomes were determined with ELISAs. SERPINA5 expression in EC and its relationship with survival outcomes were analyzed using the TCGA database and clinical EC tissue samples. The effect of SERPINA5 overexpression or exosomal SERPINA5 on EC metastasis was examined by cell migration and invasion assays in vitro. Mechanistically, overexpression of SERPINA5 or high exosomal SERPINA5 levels mediated the regulation of the integrin β1/FAK signaling pathway in EC cell lines. The therapeutic effect of exosomal SERPINA5 was determined with xenograft models.

RESULTS

This study revealed that the level of exosomal SERPINA5 was increased in the circulating plasma of EC patients. In addition, the expression of SERPINA5 was decreased in EC patients with distant metastasis, and low expression of SERPINA5 indicated worse survival. In addition, SERPINA5 was elevated in normal tissues adjacent to EC tumors. Moreover, overexpression of SERPINA5 inhibited metastatic potential of EC cell lines in vitro. Furthermore, SERPINA5 loaded on secreted exosomes reduced the metastatic ability of EC cells. Notably, overexpression of SERPINA5 or high exosomal SERPINA5 levels suppressed EC metastatic potential by suppressing integrin β1/FAK signaling pathway activation. Finally, exosomal SERPINA5 impeded tumor growth and metastasis in xenograft models.

CONCLUSIONS

Our findings revealed that a low level of SERPINA5 expression indicated poor survival outcomes in EC and that exogenous SERPINA5 loading of exosomes may be a novel therapeutic strategy for metastatic EC.

Identification of gene expression and DNA methylation of SERPINA5 and TIMP1 as novel prognostic markers in lower-grade gliomas

Background

Lower-grade gliomas (LGGs) is characteristic with great difference in prognosis. Due to limited prognostic biomarkers, it is urgent to identify more molecular markers to provide a more objective and accurate tumor classification system for LGGs.

Methods

In the current study, we performed an integrated analysis of gene expression data and genome-wide methylation data to determine novel prognostic genes and methylation sites in LGGs.

Results

To determine genes that differentially expressed between 44 short-term survivors (<2 years) and 48 long-term survivors (≥2 years), we searched LGGs TCGA RNA-seq dataset and identified 106 differentially expressed genes. SERPINA5 and TIMP1 were selected for further study. Kaplan-Meier plots showed that SERPINA5 and TIMP1 expression were significantly correlated with overall survival (OS) and relapse-free survival (RFS) in TCGA LGGs patients. We next validated the correlation between the candidate genes expression and clinical outcome in CGGA LGGs patients. Multivariate analysis showed that TIMP1 mRNA expression had a significant prognostic value independent of other variables (HR = 4.825, 95% CI = 1.370-17.000, P = 0.014). Then, differential methylation sites were identified from differentially candidate gene expression groups, and all four methylation sites were significantly negatively correlated with gene expression (spearman r <  - 0.5, P < 0.0001). Moreover, hyper-methylation of four methylation sites indicated better OS (P < 0.05), and three of them also shown statistical significantly association with better RFS, except for SERPINA5 cg15509705 (P = 0.0762).

Conclusion

Taken together, these findings indicated that the gene expression and methylation of SERPINA5 and TIMP1 may serve as prognostic predictors in LGGs and may help to precise the current histology-based tumors classification system and to provide better stratification for future clinical trials.

Identification and Quantification of Heterogeneously-methylated DNA Fragments Using Epiallele-sensitive Droplet Digital Polymerase Chain Reaction (EAST-ddPCR)

BACKGROUND/AIM

DNA methylation plays an important role in the initiation and propagation of carcinogenesis; however, the role of heterogeneously methylated epialleles is currently not well studied, also due to the lack of sensitive, unbiased and high throughput methods. Here, a newly developed droplet digital PCR (ddPCR)-based method was evaluated regarding its ability to quantify such heterogeneously methylated epialleles with sufficient analytical sensitivity and specificity.

MATERIALS AND METHODS

Genomic DNA from blood leukocytes and bone marrow aspirate of an 8-year old male with B-cell acute lymphoblastic leukemia (B-ALL) and from normal and malignant prostate cell lines were analysed using ddPCR.

RESULTS

By using these DNA samples, the specificity of an applied set of fluorescence-labeled probes was demonstrated as a proof of concept.

CONCLUSION

All individual heterogeneously-methylated epialleles were quantifiable by a set of fluorescence-labeled probes with complementary sequences to epialleles in a closed-tube and high-throughput manner. The new method named epiallele-sensitive droplet digital PCR (EAST-ddPCR) may give new insights in the generation and regulation of epialleles and may help in finding new biomarkers for the diagnosis of benign und malignant diseases.