Laminin Subunit Alpha Research Articles

Knockdown of LAMA3 enhances the sensitivity of colon cancer to oxaliplatin by regulating the Hippo-YAP pathway.

Oxaliplatin is the first-line chemotherapy for patients with colon cancer (CC). However, its resistance limits its therapeutic efficacy. Oxaliplatin resistance-associated differentially expressed genes (DEGs) in the GSE42387 and GSE227315 datasets were identified through bioinformatics methods. Functional experiments were conducted both in vitro and in vivo to evaluate the roles of laminin subunit alpha 3 (LAMA3) in drug resistance and tumorigenesis. The downstream molecular mechanisms were explored using Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis and western blot. Six hub genes associated with oxaliplatin resistance were identified, including LAMB3, ITGA3, COL4A6, COL12A1, LAMA3, and LAMC2, all of which were highly expressed in oxaliplatin-resistant CC cell lines. LAMA3 knockdown sensitized CC cells to oxaliplatin treatment, resulting in further inhibition of proliferation, migration, and invasion, as well as an increase in apoptosis in CC cells. Additionally, LAMA3 knockdown promoted the therapeutic efficacy of oxaliplatin in the CC xenograft tumor models. Mechanistically, overexpression of YAP notably counteracted the enhanced sensitivity to oxaliplatin caused by LAMA3 knockdown, indicating that LAMA3 modulates oxaliplatin sensitivity in CC through the Hippo-YAP pathway. LAMA3 knockdown promotes CC sensitivity to oxaliplatin via modulating the Hippo-YAP pathway, providing new therapeutic targets for the CC treatment.

A potential pathogenic mutation of LAMA4 in a Chinese family with dilated cardiomyopathy and conduction system disease.

Dilated cardiomyopathy (DCM) is characterized by ventricular dilation and poor systolic function. Approximately half of idiopathic DCM cases are assigned to genetic causes in familial or apparently sporadic cases, and more than 50 genes are reported to cause DCM. However, genetic basis of most DCM patients still keeps unknown and require further study. Clinical data, family histories, and blood samples were collected from the proband and family members in a Chinese family presenting with DCM and conduction system disease. A genetic analysis was performed using next generation sequencing (NGS). Bioinformatic analysis was performed to predict the pathogenic consequence of gene mutation. A missense heterozygous mutation c.652G > A (p.G218R) in Laminin Subunit Alpha-4 (LAMA4) gene was identified in proband and his 2 brothers with relevant clinical symptoms. Individuals without carrying this mutation in this family had no symptoms or cardiac structural abnormality related to DCM or conduction system disease. The p.G218R mutation is located in a conservative area within the laminin epidermal growth factor (EGF)-like domain of LAMA4 with uncertain significance in ClinVar archive. Bioinformatic analysis predicted p.G218R mutation as deleterious and pathogenic damaging in DCM patients. Our results reported a potential pathogenic mutation associated with DCM, which may provide further insight into genetic contributions of LAMA4 gene mutations to DCM phenotypes.

FOXP2 overexpression upregulates LAMA4 expression and thereby alleviates preeclampsia by regulating trophoblast behavior

Preeclampsia (PE) is a common pregnancy disorder characterized by hypertension and proteinuria. Trophoblast behavior severely affect PE progression. Transcription factor Forkhead box protein P2 (FOXP2) was involved in cell migration and invasion, but its role in PE progression remains unknown. Laminin subunit alpha 4 (LAMA4) was predicted as a downstream gene of FOXP2 and related to PE. Thus, we supposed that FOXP2 might regulate PE by regulating LAMA4. We found the decreased FOXP2 expression in patients with PE compared with healthy pregnant women. The rat model of PE was induced by L-NAME oral gavage. FOXP2 overexpression lowered systolic and diastolic blood pressure and restored pathological changes of rats with PE. Trophoblasts under the hypoxia/reoxygenation (H/R) treatment were used to mimic PE in vitro. The results revealed that FOXP2 overexpression inhibited apoptosis but promoted migration, invasion, and angiogenesis of H/R-treated trophoblasts. Dual luciferase and chromatin immunoprecipitation-polymerase chain reaction assays confirmed that FOXP2 transcriptionally upregulated the LAMA4 expression in trophoblasts. LAMA4 knockdown reversed the migration and invasion-promoting role of FOXP2 overexpression in trophoblasts with H/R treatment. Collectively, our findings suggest that the FOXP2/LAMA4 axis regulates PE by suppressing trophoblast apoptosis and promoting its migration, invasion, and angiogenesis.

Serum Levels of Protein Z, Laminin Subunit Alpha 2, Mixed Lineage Leukemia 4, and Plexin Domain Containing 2 in Newly Diagnosed and Metformin-Treated Type 2 Diabetes Patients

Diabetes mellitus is a globally prevalent disease with several parameters that may be involved in diagnosis or altered throughout disease progression. In this study, 120 patients with type 2 diabetes and healthy controls were recruited, with ages ranging from 30-65 years old. The research focused on determining levels of Protein Z (PROZ), Laminin Subunit Alpha 2 (LAMA2), Mixed Lineage Leukemia 4 (MLL4), and Plexin Domain Containing 2 (PLXDC2). Participants were divided into four groups: group I (n=30) with long-term metformin treatment, group II (n=30) with short-term metformin treatment, group III (n=30) newly diagnosed without medication, and group IV (n=30) healthy controls. Protein markers were measured by ELISA, while fasting blood glucose, lipid profiles, and HbA1c were determined by spectrophotometry and HPLC. ROC curve analysis revealed PLXDC2 had high sensitivity and specificity as a potential biomarker for diabetes diagnosis. LAMA2, MLL4, and PROZ also distinguished between diabetes patients and controls. Overall, these results identify promising biomarkers for diabetes detection and monitoring.

Familial osteochondrodysplastic and cardiomyopathic syndrome in Chianina cattle.

Skeletal dysplasia encompasses a heterogeneous group of genetic disorders characterized by an abnormal development of bones, joints, and cartilage. Two Chianina half-sibling calves from consanguineous mating with congenital skeletal malformations and cardiac abnormalities were identified. To characterize the disease phenotype, to evaluate its genetic cause, and to determine the prevalence of the deleterious alleles in the Chianina population. Two affected calves, their parents and 332 Chianina bulls. The affected animals underwent clinicopathological investigation. Whole-genome sequencing trio-approach and PCR-based assessment of the frequency of TDP-glucose 4,6-dehydratase (TGDS) and laminin subunit alpha 4 (LAMA4) alleles were performed. The cases presented with retarded growth, poor nutritional status associated with muscular atrophy and angular deformities of the hindlimbs. Radiologic examination identified generalized osteopenia and shortening of the limb long bones. Necropsy showed osteochondrodysplastic limbs and dilatation of the heart right ventricle. On histological examination, the physeal cartilages were characterized by multifocal mild to moderate loss of the normal columnar arrangement of chondrocytes. Osteopenia also was observed. Genetic analysis identified a missense variant in TGDS and a splice-site variant in LAMA4, both of which were homozygous in the 2 cases. Parents were heterozygous and allele frequency in the Chianina population for the TGDS variant was 5% and for the LAMA4 variant was 2%. Genetic findings identified 2 potentially pathogenic alleles in TGDS and LAMA4, but no clear mode of inheritance could be determined.

Analysis of serum peptidome profiles of non-metastatic and metastatic feline mammary carcinoma using liquid chromatography-tandem mass spectrometry

BackgroundFeline mammary carcinoma (FMC) is a common aggressive and highly metastatic cancer affecting female cats. Early detection is essential for preventing local and distant metastasis, thereby improving overall survival rates. While acquiring molecular data before surgery offers significant potential benefits, the current protein biomarkers for monitoring disease progression in non-metastatic FMC (NmFMC) and metastatic FMC (mFMC) are limited. The objective of this study was to investigate the serum peptidome profiles of NmFMC and mFMC using liquid chromatography-tandem mass spectrometry. A cross-sectional study was conducted to compare serum peptidome profiles in 13 NmFMC, 23 mFMC and 18 healthy cats. The liquid chromatography-tandem mass spectrometry analysis was performed on non-trypsinized samples.ResultsOut of a total of 8284 expressed proteins observed, several proteins were found to be associated with human breast cancer. In NmFMC, distinctive protein expressions encompassed double-stranded RNA-binding protein Staufen homolog 2 (STAU2), associated with cell proliferation, along with bromodomain adjacent to zinc finger domain 2A (BAZ2A) and gamma-aminobutyric acid type A receptor subunit epsilon (GABRE), identified as potential treatment targets. Paradoxically, positive prognostic markers emerged, such as complement C1q like 3 (C1QL3) and erythrocyte membrane protein band 4.1 (EPB41 or 4.1R). Within the mFMC group, overexpressed proteins associated with poor prognosis were exhibited, including B-cell lymphoma 6 transcription repressor (BCL6), thioredoxin reductase 3 (TXNRD3) and ceruloplasmin (CP). Meanwhile, the presence of POU class 5 homeobox (POU5F1 or OCT4) and laminin subunit alpha 1 (LAMA1), reported as metastatic biomarkers, was noted.ConclusionThe presence of both pro- and anti-proliferative proteins was observed, potentially indicating a distinctive characteristic of NmFMC. Conversely, proteins associated with poor prognosis and metastasis were noted in the mFMC group.

Correlation of laminin subunit alpha 3 expression in pancreatic ductal adenocarcinoma with tumor liver metastasis and survival.

The high mortality rate of pancreatic ductal adenocarcinoma (PDAC) is primarily attributed to metastasis. Laminin subunit alpha 3 (LAMA3) is known to modulate tumor progression. However, the influence of LAMA3 on liver metastasis in PDAC remains unclear. This study aimed to elucidate whether LAMA3 expression is increased in PDAC with liver metastasis. We extracted information related to LAMA3 expression levels and associated clinicopathological parameters from The Cancer Genome Atlas (TCGA) and four Gene Expression Omnibus (GEO) datasets. Clinicopathological analysis was performed; the Kaplan-Meier Plotter was used to evaluate LAMA3's prognostic effect in PDAC. We retrospectively collected clinicopathological data and tissue specimens from 117 surgically treated patients with PDAC at the Affiliated Hospital of Qingdao University. We assessed LAMA3 expression and investigated its correlation with the clinicopathological traits, clinical outcomes, and hepatic metastasis. Amplified expression of LAMA3 was observed in PDAC tissue compared with normal tissue in the TCGA and GEO databases. High LAMA3 expression was associated with poor overall survival (OS) and relapse-free survival (RFS) in patients with PDAC. LAMA3 expression was significantly enhanced in PDAC tissues than in adjacent tissues. Tumor tissues from patients with PDAC exhibiting liver metastasis showed higher LAMA3 expression than those without liver metastasis. High LAMA3 expression correlated with large tumor size and TNM stage. LAMA3 expression and liver metastasis were independent predictive factors for OS; the former was independently associated with liver metastasis. LAMA3 expression is elevated in patients with PDAC with liver metastasis and is a predictor of prognosis.

Tumor-derived mesenchymal progenitor cell-related genes in the regulation of breast cancer proliferation.

Breast cancer (BC) is one of the most common malignancies worldwide, and its development is affected in various ways by the tumor microenvironment (TME). Tumor-derived mesenchymal progenitor cells (MPCs), as the most important components of the TME, participate in the proliferation and metastasis of BC in several ways. In this study, we aimed to characterize the genes associated with tumor-derived MPCs and determine their effects on BC cells. Tumor-derived MPCs and normal breast tissue-derived mesenchymal stem cells (MSCs) were isolated from tissues specimens of patients with BC. We conducted culture and passage, phenotype identification, proliferation and migration detection, inflammatory factor release detection, and other experiments on isolated MPCs from tumors and MSCs from normal breast tissues. Three paired tumor-derived MPCs and normal breast tissue-derived MSCs were then subjected to transcriptome analysis to determine the expression profiles of the relevant genes, and quantitative real-time polymerase chain reaction (qRT-PCR) was used to further confirm gene expression. Subsequently, the overexpression plasmids were transfected into tumor-derived MPCs, and the expression of various inflammatory factors of tumor-derived MPCs and their proliferation were characterized with a cell viability test reagent (Cell Counting Kit 8). Subsequently, the transfected tumor-derived MPCs were cocultured with BC cells using a conditioned medium coculture method to clarify the role of tumor-derived MSCs in BC. Tumor-derived MPCs expressed stem cell characteristics including CD105, CD90, and CD73 and exhibited adipogenic and osteogenic differentiation in vitro. The proliferation of tumor-derived MPCs was significantly lower than that of normal breast tissue-derived MSCs, and the invasive metastatic ability was comparable; however, MPCs were found to release inflammatory factors such as interleukin 6 (IL-6) and transforming growth factor β (TGF-β). Transcriptome analysis showed that stomatin (STOM), collagen and calcium binding EGF domains 1 (CCBE1), and laminin subunit alpha 5 (LAMA5) were significantly upregulated in tumor-derived MPCs. Among them, STOM was highly expressed in tumor-derived MPCs, which mediated the slow proliferation of MPCs and promoted the proliferation of BC cells. STOM, CCBE1, and LAMA5 were highly expressed in tumor-derived MPCs, with STOM being found to retard the proliferation of MPCs but promote the proliferation of BC cells. There findings present new possibilities in targeted microenvironmental therapy for BC.

LAMA3 Promotes Tumorigenesis of Oral Squamous Cell Carcinoma by METTL3-Mediated N6-Methyladenosine Modification.

Laminin subunit alpha 3 (LAMA3) is a cancer regulator. However, its effects and regulatory pathways in oral squamous cell carcinoma (OSCC) progression remain unknown. This research aimed to determine the influence of LAMA3 regulation via methyltransferase-like 3 (METTL3) on OSCC progression. Using quantitative real-time polymerase chain reaction and bioinformatics analysis, the expression levels of LAMA3 and METTL3 in OSCC tissues were examined. The functional roles of LAMA3 and METTL3 were analyzed using cell functional experiments. Using methylated RNA immunoprecipitation and mRNA stability assays, LAMA3 and METTL3 regulation was investigated. In OSCC tissues, LAMA3 was upregulated. LAMA3 inhibition hampered OSCC cell proliferation, invasion, and migration while its overexpression facilitated OSCC cell progression. METTL3 serves as a crucial upstream regulator of LAMA3 in OSCC and upregulates LAMA3 expression via an m6A-dependent mechanism. The low METTL3 expression partially restored the enhanced malignant phenotype induced by LAMA3 overexpression. Our findings indicate that METTL3 and LAMA3 act as pro-oncogenic factors in OSCC, with METTL3 promoting OSCC malignancy via m6A modification-dependent stabilization of LAMA3 transcripts, representing a novel regulatory mechanism in OSCC.

FAT4 loss initiates hepatocarcinogenesis through the switching of canonical to noncanonical WNT signaling pathways.

Mutation and downregulation of FAT atypical cadherin 4 (FAT4) are frequently detected in HCC, suggesting a tumor suppressor role of FAT4. However, the underlying molecular mechanism remains elusive. CRISPR-Cas9 system was used to knockout FAT4 (FAT4-KO) in a normal human hepatic cell line L02 to investigate the impact of FAT4 loss on the development of HCC. RNA-sequencing and xenograft mouse model were used to study gene expression and tumorigenesis, respectively. The mechanistic basis of FAT4 loss on hepatocarcinogenesis was elucidated using in vitro experiments. We found that FAT4-KO disrupted cell-cell adhesion, induced epithelial-mesenchymal transition, and increased expression of extracellular matrix components. FAT4-KO is sufficient for tumor initiation in a xenograft mouse model. RNA-sequencing of FAT4-KO cells identified PAK6-mediated WNT/β-catenin signaling to promote tumor growth. Suppression of PAK6 led to β-catenin shuttling out of the nucleus for ubiquitin-dependent degradation and constrained tumor growth. Further, RNA-sequencing of amassed FAT4-KO cells identified activation of WNT5A and ROR2. The noncanonical WNT5A/ROR2 signaling has no effect on β-catenin and its target genes (CCND1 and c-Myc) expression. Instead, we observed downregulation of receptors for WNT/β-catenin signaling, suggesting the shifting of β-catenin-dependent to β-catenin-independent pathways as tumor progression depends on its receptor expression. Both PAK6 and WNT5A could induce the expression of extracellular matrix glycoprotein, laminin subunit alpha 4. Laminin subunit alpha 4 upregulation in HCC correlated with poor patient survival. Our data show that FAT4 loss is sufficient to drive HCC development through the switching of canonical to noncanonical Wingless-type signaling pathways. The findings may provide a mechanistic basis for an in-depth study of the two pathways in the early and late stages of HCC for precise treatment.

Contribution of common and rare variants to Asian neovascular age-related macular degeneration subtypes

Neovascular age-related macular degeneration (nAMD), along with its clinical subtype known as polypoidal choroidal vasculopathy (PCV), are among the leading causes of vision loss in elderly Asians. In a genome-wide association study (GWAS) comprising 3,128 nAMD (1,555 PCV and 1,573 typical nAMD), and 5,493 controls of East Asian ancestry, we identify twelve loci, of which four are novel (P , < , 1.19times {10}^{-8}). Substantial genetic sharing between PCV and typical nAMD is noted (rg = 0.666), whereas collagen extracellular matrix and fibrosis-related pathways are more pronounced for PCV. Whole-exome sequencing in 259 PCV patients revealed functional rare variants burden in collagen type I alpha 1 chain gene (COL1A1; P=1.05times {10}^{-6}) and potential enrichment of functional rare mutations at AMD-associated loci. At the GATA binding protein 5 (GATA5) locus, the most significant GWAS novel loci, the expressions of genes including laminin subunit alpha 5 (Lama5), mitochondrial ribosome associated GTPase 2 (Mtg2), and collagen type IX alpha 3 chain (Col9A3), are significantly induced during retinal angiogenesis and subretinal fibrosis in murine models. Furthermore, retinoic acid increased the expression of LAMA5 and MTG2 in vitro. Taken together, our data provide insights into the genetic basis of AMD pathogenesis in the Asian population.

Investigating the Prognosis Gene Profile of Triple-Negative Breast Cancer

Background: Current therapeutic strategies have poor effects in triple-negative breast cancer (TNBC) patients due to lack of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor-2 expression. Identification of novel genes of TNBC prognosis aids in the development of effective treatment strategies. Aim: We aim at explore key genes related to TNBC recurrence. Methods: RNAseq and clinical characteristics data were derived from The Cancer Genome Atlas Breast Invasive Carcinoma project. Ninety-seven TNBC patients were included. We used DESeq2 and Cox regression to identify significant genes to TNBC recurrence. Pathway enrichment analysis and protein–protein interaction plot were conducted to understand the functions of target genes. Results: We discovered top nine important genes for TNBC recurrence. Lower mRNA expression of potassium voltage-gated channel subfamily Q member 5, H3 clustered histone 10, and ADP-ribosylation factor-like protein 17 and higher mRNA expression of synuclein beta, interleukin 6 (IL-6), casein kappa, RHOC, phosphodiesterase 8B, and laminin subunit alpha 3 (LAMA3) were associated with higher risk of recurrence. IL-6, LAMA3, and Ras homolog family member V (RHOV) genes out of nine candidate genes can make the best prediction of TNBC recurrence (area under receiver operating characteristic curve: 0.95, sensitivity: 0.89 and specificity: 0.97). The top three significant Gene Ontology (GO) pathways are nucleosome, ion gated channel activity, and epidermis development. Significant GO pathways can be categorized into four functions: cell–cell adhesion, cell transportation, cell proliferation, ion channel and transporter, and immune. Conclusion: We discovered that the gene set of IL6, LAMA3, and RHOV can accurately predict TNBC recurrence. These genes warrant further study to confirm their causal association with TNBC prognosis and possible treatment targets.

Research Progress on the Role of Laminin Subunit Alpha 4 in Diseases

Laminin subunit alpha 4 (LAMA4),a member of the laminin family,is present in the intercellular matrix of adult tissues as a major component of basement membrane.LAMA4 is involved in the adhesion of cells and can bind to corresponding integrins to activate relevant signaling pathways,playing an essential role in the growth,proliferation,and migration of cells.It has been demonstrated that LAMA4 is associated with the occurrence and development of a variety of diseases including tumors,and the expression of LAMA4 can be used as a biomarker of tumor diagnosis and prognosis.This paper summarizes the current research progress in LAMA4 with the focus on the relationship between LAMA4 and diseases,especially tumor,with a view to provide new directions for the future research.

LINC00629 protects osteosarcoma cell from ER stress-induced apoptosis and facilitates tumour progression by elevating KLF4 stability

BackgroundEscaping from ER stress-induced apoptosis plays an important role in the progression of many tumours. However, its molecular mechanism in osteosarcoma remains incompletely understood.MethodsThe molecular mechanism was investigated using RNA sequencing, qRT–PCR and Western blot assays. The relationship between LINC00629 and KLF4 was investigated using RNA pulldown and ubiquitylation assays. The transcriptional regulation of laminin subunit alpha 4 (LAMA4) by KLF4 was identified using bioinformatic analysis, a luciferase assay, and a chromatin immunoprecipitation assay.ResultsHere, we demonstrated that LINC00629 was increased under ER stress treatment. Elevated LINC00629 inhibited ER stress-induced osteosarcoma cell apoptosis and promoted clonogenicity and migration in vitro and in vivo. Further mechanistic studies indicated that LINC00629 interacted with KLF4 and suppressed its degradation, which led to a KLF4 increase in osteosarcoma. In addition, we also found that KLF4 upregulated LAMA4 expression by directly binding to its promoter and that LINC00629 inhibited ER stress-induced apoptosis and facilitated osteosarcoma cell clonogenicity and metastasis by activating the KLF4-LAMA4 pathway.ConclusionCollectively, our data indicate that LINC00629 is a critical long noncoding RNA (lncRNA) induced by ER stress and plays an oncogenic role in osteosarcoma cell by activating the KLF4-LAMA4 axis.

Establishment of induced pluripotent stem cell lines from an ARVC patient carrying a heterozygous variant in LAMA2 gene

Using peripheral blood mononuclear cell (PBMC) reprogramming technology, a human-induced pluripotent stem cell (iPSC) line was produced from a patient who presents classic clinical features of arrhythmogenic right ventricular cardiomyopathy (ARVA) and carries a de novo laminin subunit alpha 2 (LAMA2) heterozygous mutation (NM_000426.3: c.8842G > A, p.G2948S). This mutation was not inherited from his parents, who also present normal cardiac phenotype. This iPSC line demonstrates a normal karyotype. Pluripotency and differentiation capacity has been confirmed in vitro. This cell line can help in efforts to understand the pathogenic mechanism between LAMA2 mutation and ARVC.

An artificial LAMA2-GelMA hydrogel microenvironment for the development of pancreatic endocrine progenitors

The biomimetic pancreatic microenvironment improves the differentiation efficiency and function of human embryonic stem cell-derived β-cells (SC-β cells). Thus, a laminin subunit alpha 2-gelatin methacrylate (LAMA2-GelMA) hybrid hydrogel as a bionics carrier for the formation and maturation of endocrine lineage was developed in our research, based on pancreas proteomics analysis of postnatal mice. Pancreatic endocrine cells cultured on the hybrid hydrogel in vitro, which was composed of 0.5 μg/mL LAMA2 protein and 4% GelMA, the expression of transcription factors (TFs), including NKX6.1, NKX6.2, and NEUROD1 were upregulated. Single-cell transcriptomics was performed after LAMA2 knockdown during the early differentiation of pancreatic progenitor (PP) cells, a marked decrease in the forkhead box protein A2 (FOXA2+)/GATA-binding factor 6 (GATA6+) cluster was detected. Also, we clarified that as a receptor of LAMA2, integrin subunit alpha 7 (ITGA7) participated in Integrin-AKT signaling transduction and influenced the protein levels of FOXA2 and PDX1. In vivo experiments showed that, PP cells encapsulated in the LAMA2-GelMA hydrogel exhibited higher serum C-peptide levels compared to the GelMA and Matrigel groups in nude mice and reversed hyperglycemia more quickly in STZ-induced diabetic nude mice. Taken together, our findings highlighted the feasibility of constructing a pancreas-specific microenvironment based on proteomics and tissue engineering for the treatment of diabetes.

Epigenetic regulation of LINC01270 in breast cancer progression by mediating LAMA2 promoter methylation and MAPK signaling pathway.

Application of long non-coding RNAs (lncRNAs) for modulation of breast cancer (BC) has attracted much attention. Here, we probed into the role and underlying mechanism of long intergenic non-coding RNA 01270 (LINC01270) in BC. With the help of bioinformatics tools, we identified laminin subunit alpha 2 (LAMA2) as a BC-related differentially expressed gene to discern the effect of LAMA2 in BC cells. LAMA2 was initially poorly expressed while LINC01270 was highly expressed in BC. BC cells were subsequently treated with sh-LINC01270 or/and sh-LAMA2 for exploration of their regulatory mechanism in BC, which unfolded that LINC01270 inhibition up-regulated LAMA2 and inactivated the MAPK signaling pathway to suppress malignant characteristics of BC cells. Functional assays demonstrated that LINC01270 bound to DNMT1, DNMT3a, and DNMT3b promoted the methylation of CpG islands in LAMA2 promoter and inhibited the LAMA2 expression. Moreover, our data suggested that LAMA2 suppressed MAPK signaling pathway to inhibit BC cell malignant characteristics. The in vitro results were re-produced with the help of the in vivo experimentations. In conclusion, LINC01270 silencing inhibited the methylation of LAMA2 promoter to suppress the activation of MAPK signaling pathway, which subsequently restrained the BC progression. 1, Overexpression of LAMA2 inhibits malignant features of BC cells. 2, LINC01270 promotes LAMA2 promoter methylation by recruiting DNMTs to the LAMA2 promoter region. 3, 5-aza-dc reverses the promotion of LAMA2 promoter methylation by LINC01270. 4, LAMA2 inhibits malignant features of BC cells by suppressing the activation of MAPK signaling pathway.

Abstracts from the NIH Office of Research on Women's Health 2022 Annual BIRCWH Meeting:Building Interdisciplinary Research Careers in Women's Health November 2, 2022

Abstracts from the NIH Office of Research on Women's Health 2022 Annual BIRCWH Meeting:Building Interdisciplinary Research Careers in Women's Health November 2, 2022

FC017: Adaptive Remodelling of Mesangial Extracellular Matrix Proteoglycan Composition during IGA Nephropathy

Abstract BACKGROUND AND AIMS IgA nephropathy (IgAN) is characterized by the deposition of galactose deficient IgA (gd-IgA1) containing immune complexes in the mesangium leading to activation of the mesangial cells and local inflammation. Hallmarks of the disease are increased by mesangial proliferation and matrix expansion. The exact composition of the mesangial matrix is not known and nor is the full role of the expansion in disease progression. One important group of proteins found in extracellular matrixes is proteoglycans (PGs). PGs are composed of a core protein to which one or several negatively charged glycosaminoglycan (GAG) side chains are attached. Both the core protein and GAGs determine the properties of PGs and changes in the amount and structure of PGs could influence disease progression. In this study, we aimed to elucidate changes in the PG expression in the glomerulus in IgAN as well as how gd-IgA1 affects the mesangial cells’ PG expression. METHOD Using previously published glomerular transcriptomic data from patients with IgAN compared to healthy controls we investigated PG expression as well as changes in expression on a glomerular level [1]. Secondly, we investigated how gd-IgA1 affects the PG production of the cells in vitro using data from a previously published proteomic data set [1] as well as new in vivo experiments using real-time PCR as well as immunohistochemistry. To further explore the effects on PGs in IgAN, we employed a novel glycoproteomic approach that provides the combined characterization of GAG linkage regions and core protein identities in complex sample matrices. RESULTS We found 31 PGs to be expressed in the human glomeruli and of those 6 PGs were found to be significantly regulated in patients with IgAN. SDC1 (syndecan-1), was downregulated, while MXRA5 (matrix-remodeling associated 5), CD44 (CD44), TNC (tenascin C), FMOD (fibromodulin) and PRELP (PRELP) were up-regulated. The proteomic data set on mesangial cells treated with gd-IgA1 revealed that mesangial cells in vitro expressed 19 PGs and of those 10 were significantly regulated. Chondroitin sulfate proteoglycan 4, glypican-1, agrin, aggrecan, versican, lumican, protein AMBP, tenascin, collagen alpha-1(VII) chain and laminin subunit alpha-4. All of the significantly regulated PGs had an increased expression, except aggrecan, which was down-regulated. An interesting finding from the glycoproteomic experiments was the identification of collagen VII as a novel PG carrying chondroitin GAG in mesangial cells. In addition, immunohistochemistry revealed that gd-IgA1 treatment of mesangial cells does not lead to a total increase in GAGs, but rather to a switch from heparan sulfate to chondroitin sulfate GAGs. CONCLUSION In conclusion, this study gives a comprehensive view of the PGs expressed by mesangial cells and their alterations in response to gd-IgA1 as part of the expansion of the mesangium in IgAN. The switch of heparan sulfate GAGs to chondroitin sulfate GAGs is an interesting finding but the role of this switch needs further investigation.

A Pilot Study of Blood-Based Methylation Markers Associated With Pancreatic Cancer.

Over the past several decades in the United States, incidence of pancreatic cancer (PCa) has increased, with the 5-year survival rate remaining extremely low at 10.8%. Typically, PCa is diagnosed at an advanced stage, with the consequence that there is more tumor heterogeneity and increased probability that more cells are resistant to treatments. Risk factors for PCa can serve as a way to select a high-risk population and develop biomarkers to improve early detection and treatment. We focus on blood-based methylation as an approach to identify a marker set that can be obtained in a minimally invasive way (through peripheral blood) and could be applied to a high-risk subpopulation [those with recent onset type 2 diabetes (DM)]. Blood samples were collected from 30 patients, 15 had been diagnosed with PCa and 15 had been diagnosed with recent onset DM. HumanMethylationEPIC Beadchip (Illumina, CA, United States) was used to quantify methylation of approximately 850,000 methylation sites across the genome and to analyze methylation markers associated with PCa or DM or both. Exploratory analysis conducted to propose importance of top CpG (5′—C—phosphate—G—3′) methylation site associated genes and visualized using boxplots. A methylation-based age predictor was also investigated for ability to distinguish disease groups from controls. No methylation markers were observed to be significantly associated with PCa or new onset diabetes compared with control the respective control groups. In our exploratory analysis, one methylation marker, CpG04969764, found in the Laminin Subunit Alpha 5 (LAMA5) gene region was observed in both PCa and DM Top 100 methylation marker sets. Modification of LAMA5 methylation or LAMA5 gene function may be a way to distinguish those recent DM cases with and without PCa, however, additional studies with larger sample sizes and different study types (e.g., cohort) will be needed to test this hypothesis.