Long non-coding RNA A1BG-AS1 promotes tumorigenesis in breast cancer by sponging microRNA-485-5p and consequently increasing expression of FLOT1 expression

Exosome-derived lncRNA A1BG-AS1 attenuates the progression of prostate cancer depending on ZC3H13-mediated m6A modification

BACKGROUND

Exosome-derived long non-coding RNAs (lncRNAs) and N6-methyladenosine (m6A) modifications of lncRNAs have been shown crucial functions in prostate cancer (PCa). Herein, we aim to investigate the detailed mechanism of exosome-derived lncRNA A1BG-AS1 in PCa process.

METHODS

PCa cell exosomes were extracted, exosomal marker proteins (CD63, CD9) were detected utilizing western blotting, and exosomes with overexpressing A1BG-AS1 were co-cultured with targeted PCa cells. qRT-PCR was used to detect A1BG-AS1 expression and m6A methyltransferase ZC3H13 in PCa. Transwell, colony formation and CCK-8 assays were utilized to assess the invasion, migration, and proliferation ability of PCa cells. Then, we performed actinomycin D and MeRIP assays to analyze the regulatory effect of ZC3H13 on A1BG-AS1 mRNA stability and m6A modification level.

RESULTS

We observed that A1BG-AS1 and ZC3H13 expression was restricted in PCa tumors. The invasion, proliferation and migratory capacities of PCa cells could be inhibited by up-regulating A1BG-AS1 or by co-culturing with exosomes that up-regulate A1BG-AS1. Additionally, ZC3H13 promoted stable A1BG-AS1 expression by regulating the m6A level of A1BG-AS1.

CONCLUSION

Exosomal A1BG-AS1 was m6A-modified by the m6A methyltransferase ZC3H13 to stabilize expression and thus prevent PCa cell malignancy. These findings offer a possible target for clinical therapy of PCa.

A1BG-AS1 promotes adriamycin resistance of breast cancer by recruiting IGF2BP2 to upregulate ABCB1 in an m6A-dependent manner

Adriamycin (ADR) resistance is an obstacle for chemotherapy of breast cancer (BC). ATP binding cassette subfamily B member 1 (ABCB1) expression is indicated to be closely related to the drug resistance of cancer cells. The current work intended to explore the molecular mechanisms to regulate ABCB1 in BC cells with ADR resistance. We found that long noncoding RNA (lncRNA) A1BG antisense RNA 1 (A1BG-AS1) is upregulated in ADR resistant BC cell lines (MCF-7/ADR, MDA-MB-231/ADR). A1BG-AS1 knockdown enhanced the ADR sensitivity by suppressing the viability, proliferation potential and migration ability, and facilitating cell apoptosis in BC. Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) is known to be an m6A reader to modulate the stability of mRNA transcripts in an m6A-dependent manner, which was a shared RNA binding protein (RBP) for A1BG-AS1 and ABCB1. The interaction of IGF2BP2 with A1BG-AS1 or ABCB1 was explored and verified using RNA pulldown and RNA immunoprecipitation (RIP) assays. ABCB1 mRNA and protein expression was positively regulated by A1BG-AS1 and IGF2BP2 in BC cells. ABCB1 mRNA expression was stabilized by A1BG-AS1 via recruiting IGF2BP2 in an m6A-dependent manner. Moreover, rescue assays demonstrated that A1BG-AS1 enhanced BC ADR resistance by positively modulating ABCB1. Xenograft mouse models were used to explore whether A1BG-AS1 affected the ADR resistance in BC in vivo. The findings indicated that A1BG-AS1 silencing inhibited tumor growth and alleviated ADR resistance in vivo. In conclusion, A1BG-AS1 enhances the ADR resistance of BC by recruiting IGF2BP2 to upregulate ABCB1 in an m6A-dependent manner.

Unveiling the Genetic Complexity of Teratozoospermia: Integrated Genomic Analysis Reveals Novel Insights into lncRNAs' Role in Male Infertility

Male infertility is a global health issue, affecting over 20 million men worldwide. Genetic factors are crucial in various male infertility forms, including teratozoospermia. Nonetheless, the genetic causes of male infertility remain largely unexplored. In this study, we employed whole-genome sequencing and RNA expression analysis to detect differentially expressed (DE) long-noncoding RNAs (lncRNAs) in teratozoospermia, along with mutations that are exclusive to teratozoospermic individuals within these DE lncRNAs regions. Bioinformatic tools were used to assess variants' impact on lncRNA structure, function, and lncRNA-miRNA interactions. Our analysis identified 1166 unique mutations in teratozoospermic men within DE lncRNAs, distinguishing them from normozoospermic men. Among these, 64 variants in 23 lncRNAs showed potential regulatory roles, 7 variants affected 4 lncRNA structures, while 37 variants in 17 lncRNAs caused miRNA target loss or gain. Pathway Enrichment and Gene Ontology analyses of the genes targeted by the affected miRNAs revealed dysregulated pathways in teratozoospermia and a link between male infertility and cancer. This study lists novel variants and lncRNAs associated for the first time with teratozoospermia. These findings pave the way for future studies aiming to enhance diagnosis and therapy in the field of male infertility.

A1BG-AS1 promotes the biological functions of osteosarcoma cells via regulating the microRNA-148a-3p/USP22 axis and stabilizing the expression of SIRT1 through deubiquitinase function

BACKGROUND

The study aims to explore the role of A1BG antisense RNA 1 (A1BG-AS1), microRNA (miR)-148a-3p and ubiquitin-specific protease 22 (USP22) on osteosarcoma (OS) cell growth.

RESEARCH DESIGN & METHODS

A1BG-AS1, miR-148a-3p, USP22, and silent information regulator 2 homolog 1 (SIRT1) levels in OS tissues and cells were determined. The effects of A1BG-AS1, miR-148a-3p, and USP22 on the biological functions of OS cells were examined by functional assays. In vivo assay was conducted to observe the effect of A1BG-AS1 on OS growth in vitro. The relationship of A1BG-AS1, miR-148a-3p, and USP22 was analyzed by bioinformatics analysis, RNA-fluorescence in situ hybridization, luciferase activity, and RNA binding protein immunoprecipitation assays. The relation between USP22 and SIRT1 was evaluated by immunoprecipitation.

RESULTS

A1BG-AS1 and USP22 were highly expressed, and miR-148a-3p was lowly expressed in OS tissues and cells. Down-regulation of A1BG-AS1 and USP22 or up-regulation of miR-148a-3p impaired the malignant behaviors of OS cells. A1BG-AS1 sponged miR-148a-3p, and miR-148a-3p targeted USP22, thereby inhibiting USP22 expression. Up-regulating USP22 reversed the A1BG-AS1 suppression-induced phenotypic inhibition of OS cells. USP22 affected the biological functions of OS cells by deubiquitinating SIRT1.

CONCLUSION

A1BG-AS1 facilitates the biological functions of OS cells via mediating the miR-148a-3p/USP22 axis.

Construction of lipid raft-coupled agarose gels as bioaffinity chromatography materials and validation with tropomyosin-related kinase A-targeted drugs

In order to improve the separation process of affinity chromatography that has silica as the main carrier material, we sought to construct Lipid Rafts@CNBr-Sepharose 4B affinity chromatography model. We extracted the lipid rafts from U251 cells with a descaler method and sucrose density gradient centrifugation. Afterwards, it was discovered via immunofluorescence that the lipid rafts contain a large amount of tropomyosin-related kinase A (TrkA) protein. Also, agarose powder in the lyophilised state was pretreated, before the lipid rafts were coupled to the agarose gel in a coupling buffer of alkaline pH. CNBr-Sepharose 4B affinity gel packing was characterised using UV spectrophotometric, immunofluorescence and scanning electron microscopic techniques, wherein and the results showed that the lipid rafts were successfully coupled to the agarose gels. Three compounds were used to verify the specific sorption of Sepharose 4B and CNBr-Sepharose 4B, which showed no specific sorption on the materials. Of note, the prepared Lipid Rafts@CNBr-Sepharose 4B agarose gels packed with TrkA-rich target proteins could be successfully validated for the active drug gefitinib with high affinity sorption efficiency and eluted with good recovery and reproducibility. This study broadens the range of affinity chromatography carrier materials and provides a reference for research in active drug screening.

Epigenome-wide analysis of maternal exposure to green space during gestation and cord blood DNA methylation in the ENVIRONAGE cohort

BACKGROUND

DNA methylation programming is sensitive to prenatal life environmental influences, but the impact of maternal exposure to green space on newborns DNA methylation has not been studied yet.

METHODS

We conducted a meta-epigenome-wide association study (EWAS) of maternal exposure to green space during gestation with cord blood DNA methylation in two subsets of the ENVIRONAGE cohort (N = 538). Cord blood DNA methylation was measured by Illumina HumanMethylation 450K in one subset (N = 189) and EPICarray in another (N = 349). High (vegetation height>3 m (m)), low (vegetation height<3 m) and total (including both) high-resolution green space exposures during pregnancy were estimated within 100 m and 1000 m distance around maternal residence. In each subset, we sought cytosine-phosphate-guanine (CpG) sites via linear mixed models adjusted on newborns' sex, ethnicity, gestational age, season at delivery, sampling day, maternal parity, age, smoking, education, and estimated blood cell proportions. EWASs results were meta-analysed via fixed-effects meta-analyses. Differentially methylated regions (DMRs) were identified via ENmix-combp and DMRcate algorithms. Sensitivity analyses were additionally adjusted on PM_2.5, distance to major roads, urbanicity and neighborhood income. In the 450K subset, cord blood expression of differentially methylated genes was measured by Agilent microarrays and associated with green space.

RESULTS

147 DMRs were identified, 85 of which were still significant upon adjustment for PM_2.5, distance to major roads, urbanicity and neighborhood income, including HLA-DRB5, RPTOR, KCNQ1DN, A1BG-AS1, HTR2A, ZNF274, COL11A1 and PRSS36 DMRs. One CpG reached genome-wide significance, while 54 CpGs were suggestive significant (p-values<1e-05). Among them, a CpG, hypermethylated with 100 m buffer total green space, was annotated to PAQR9, whose expression decreased with 1000 m buffer low green space (p-value = 1.45e-05).

CONCLUSIONS

Our results demonstrate that maternal exposure to green space during pregnancy is associated with cord blood DNA methylation, mainly at loci organized in regions, in genes playing important roles in neurological development (e.g., HTR2A).