Cancer multidrug resistance (MDR) impairs the therapeutic efficacy of various chemotherapeutics. Novel approaches, particularly the development of MDR reversal agents, are critically needed to address this challenge. This study demonstrates that tenacissoside I (TI), a compound isolated from Marsdenia tenacissima (Roxb.) Wight et Arn, traditionally used in clinical practice as an ethnic medicine for cancer treatment, exhibits significant MDR reversal effects in ABCB1-mediated MDR cancer cells. TI reversed the resistance of SW620/AD300 and KBV200 cells to doxorubicin (DOX) and paclitaxel (PAC) by downregulating ABCB1 expression and reducing ABCB1 drug transport function. Mechanistically, protein arginine methyltransferase 1 (PRMT1), whose expression correlates with poor prognosis and shows positive association with both ABCB1 and EGFR expressions in tumor tissues, was differentially expressed in TI-treated SW620/AD300 cells. SW620/AD300 and KBV200 cells exhibited elevated levels of EGFR asymmetric dimethylarginine (aDMA) and enhanced PRMT1-EGFR interaction compared to their parental cells. Moreover, TI-induced PRMT1 downregulation impaired PRMT1-mediated aDMA of EGFR, PRMT1-EGFR interaction, and EGFR downstream signaling in SW620/AD300 and KBV200 cells. These effects were significantly reversed by PRMT1 overexpression. Additionally, TI demonstrated resistance reversal to PAC in xenograft models without detectable toxicities. This study establishes TI's MDR reversal effect in ABCB1-mediated MDR human cancer cells through inhibition of PRMT1-mediated aDMA of EGFR, suggesting TI's potential as an MDR modulator for improving chemotherapy outcomes.
Humans ; Protein-Arginine N-Methyltransferases/antagonists & inhibitors* ; Drug Resistance, Neoplasm/drug effects* ; ErbB Receptors/genetics* ; Animals ; Cell Line, Tumor ; Drug Resistance, Multiple/drug effects* ; Methylation/drug effects* ; Saponins/administration & dosage* ; Mice ; Mice, Nude ; Mice, Inbred BALB C ; ATP Binding Cassette Transporter, Subfamily B/genetics* ; Doxorubicin/pharmacology* ; Paclitaxel/pharmacology* ; Female ; Repressor Proteins

OBJECTIVE: To explore the genetic etiology for a child presenting with motor retardation, language delay, intellectual disability, and dysmorphic features. METHODS: A child presented at Linyi People's Hospital in June 2022 was selected as the study subject. Clinical data of the child was collected. Peripheral blood samples were obtained from the child and her parents. Following extraction of genomic DNA, whole-exome sequencing (WES) was carried out. Candidate variant was validated by Sanger sequencing. Amniotic fluid samples were obtained from the mother's subsequent pregnancies for prenatal diagnosis. This study has been reviewed and approved by the Medical Ethics Committee of Linyi People's Hospital (Ethics No.: 2019-134). RESULTS: The proband was a 2-year-old girl showing developmental delays in motor, language, and intellectual domains, strabismus, hypertelorism, hearing impairment, obesity, and brachymesophalangy of the fifth finger. Magnetic resonance imaging revealed abnormalities of the white matter. Chromosomal microarray analysis (CMA) identified a 15q26.3 duplication (chr15:101562020_102060896 × 3) inherited from her mother. WES has uncovered a heterozygous c.1931A>G (p.Tyr644Cys) variant in the FBXO11 gene. Sanger sequencing confirmed the variant to be de novo in origin. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was classified as likely pathogenic. Prenatal diagnosis revealed that the fetuses from the mother's second and third pregnancies did not harbor the same variant. CONCLUSION The c.1931A>G (p.Tyr644Cys) variant of the FBXO11 gene probably underlay the abnormal phenotype in the child. Based on its genotype and phenotype, the proband was diagnosed with Intellectual developmental disorder with dysmorphic facies and behavioral abnormalities.
Humans ; Female ; Intellectual Disability/genetics* ; Child, Preschool ; F-Box Proteins/genetics* ; Protein-Arginine N-Methyltransferases/genetics* ; Exome Sequencing

BACKGROUNDProtein arginine methyltransferases 1 (PRMT1) is over-expressed in a variety of cancers, including lung cancer, and is correlated with a poor prognosis of tumor development. This study aimed to investigate the role of PRMT1 in nonsmall cell lung cancer (NSCLC) migration in vitro.

METHODSIn this study, PRMT1 expression in the NSCLC cell line A549 was silenced using lentiviral vector-mediated short hairpin RNAs. Cell migration was measured using both scratch wound healing and transwell cell migration assays. The mRNA expression levels of matrix metalloproteinase 2 (MMP-2) and tissue inhibitor of metalloproteinase 1, 2 (TIMP1, 2) were measured using quantitative real-time reverse transcription-polymerase chain reaction. The expression levels of protein markers for epithelial-mesenchymal transition (EMT) (E-cadherin, N-cadherin), focal adhesion kinase (FAK), Src, AKT, and their corresponding phosphorylated states were detected by Western blot.

RESULTSCell migration was significantly inhibited in the PRMT1 silenced group compared to the control group. The mRNA expression of MMP-2 decreased while TIMP1 and TIMP2 increased significantly. E-cadherin mRNA expression also increased while N-cadherin decreased. Only phosphorylated Src levels decreased in the silenced group while FAK or AKT remained unchanged.

CONCLUSIONSPRMT1-small hairpin RNA inhibits the migration abilities of NSCLC A549 cells by inhibiting EMT, extracellular matrix degradation, and Src phosphorylation in vitro.

Blotting, Western ; Carcinoma, Non-Small-Cell Lung ; enzymology ; genetics ; Cell Line ; Cell Movement ; genetics ; physiology ; Epithelial-Mesenchymal Transition ; genetics ; physiology ; Extracellular Matrix Proteins ; metabolism ; Humans ; Protein-Arginine N-Methyltransferases ; genetics ; metabolism ; RNA, Small Interfering ; genetics ; physiology

OBJECTIVETo discuss the effect of matrine on nitric oxide (NO) and asymmetric methylarginine (ADMA) metabolism pathways in serum and tissues of mice with lipopolysaccharide (LPS) -induced intestine tissue inflammation.

METHODKunming mice were randomly divided into five groups: the normal control group, the LPS group and matrine (80, 40, 20 mg x kg(-1) x d(-1)) groups. The mice were intragastrically administered with drugs for 3 d (distilled water of the same volume for the normal control group and the LPS group). One hour after the last intragastrical administration, normal saline or LPS (1 mg x kg(-1)) were intraperitoneally injected. Twelve hours later, serum and tissues were collected to determine NO and ADMA levels and observe the pathological changes of intestinal tissues. The Western blot method was adopted to detect the protein expressions of arginine methyltransferases 1 (PRMT1) and dimethylarginine dimethylaminohydrolase 2 (DDAH2) in intestinal tissues.

RESULTCompared with the model group, matrine (80, 40, 20 mg x kg(-1) x d(-1)) groups showed lower NO content in serum and tissues, higher ADMA level in serum and increased PRMT1 expression in intestinal tissues, but without effect on DDAH2 expression.

CONCLUSIONMatrine could inhibit LPS-induced intestine tissue inflammation in mice. Its action mechanism is related to the decreased NO content in serum and tissues and increased ADMA level in serum and PRMT1 expression in intestinal tissues.

Alkaloids ; administration & dosage ; Animals ; Arginine ; analogs & derivatives ; blood ; metabolism ; Humans ; Inflammation ; Intestinal Diseases ; drug therapy ; enzymology ; immunology ; metabolism ; Intestines ; drug effects ; enzymology ; immunology ; metabolism ; Lipopolysaccharides ; adverse effects ; Male ; Mice ; Nitric Oxide ; blood ; metabolism ; Protein-Arginine N-Methyltransferases ; genetics ; metabolism ; Quinolizines ; administration & dosage

Protein arginine methylation is important for a variety of cellular processes including transcriptional regulation, mRNA splicing, DNA repair, nuclear/cytoplasmic shuttling and various signal transduction pathways. However, the role of arginine methylation in protein biosynthesis and the extracellular signals that control arginine methylation are not fully understood. Basic fibroblast growth factor (bFGF) has been identified as a potent stimulator of myofibroblast dedifferentiation into fibroblasts. We demonstrated that symmetric arginine dimethylation of eukaryotic elongation factor 2 (eEF2) is induced by bFGF without the change in the expression level of eEF2 in mouse embryo fibroblast NIH3T3 cells. The eEF2 methylation is preceded by ras-raf-mitogen-activated protein kinase kinase (MEK)-extracellular signal-regulated kinase (ERK1/2)-p21(Cip/WAF1) activation, and suppressed by the mitogen-activated protein kinase (MAPK) inhibitor PD98059 and p21(Cip/WAF1) short interfering RNA (siRNA). We determined that protein arginine methyltransferase 7 (PRMT7) is responsible for the methylation, and that PRMT5 acts as a coordinator. Collectively, we demonstrated that eEF2, a key factor involved in protein translational elongation is symmetrically arginine-methylated in a reversible manner, being regulated by bFGF through MAPK signaling pathway.
Animals ; Arginine ; Cell Dedifferentiation ; Cyclin-Dependent Kinase Inhibitor p21/genetics/metabolism ; Elongation Factor 2 Kinase/*metabolism ; Fibroblast Growth Factor 2/*metabolism ; Fibroblasts/*metabolism/pathology ; Flavonoids/pharmacology ; MAP Kinase Signaling System/drug effects/genetics ; Methylation ; Mice ; Mitogen-Activated Protein Kinases/antagonists & inhibitors ; Myofibroblasts/pathology ; NIH 3T3 Cells ; Protein Methyltransferases/*metabolism ; Protein-Arginine N-Methyltransferases/*metabolism ; RNA, Small Interfering/genetics

Protein arginine methylation is important for a variety of cellular processes including transcriptional regulation, mRNA splicing, DNA repair, nuclear/cytoplasmic shuttling and various signal transduction pathways. However, the role of arginine methylation in protein biosynthesis and the extracellular signals that control arginine methylation are not fully understood. Basic fibroblast growth factor (bFGF) has been identified as a potent stimulator of myofibroblast dedifferentiation into fibroblasts. We demonstrated that symmetric arginine dimethylation of eukaryotic elongation factor 2 (eEF2) is induced by bFGF without the change in the expression level of eEF2 in mouse embryo fibroblast NIH3T3 cells. The eEF2 methylation is preceded by ras-raf-mitogen-activated protein kinase kinase (MEK)-extracellular signal-regulated kinase (ERK1/2)-p21(Cip/WAF1) activation, and suppressed by the mitogen-activated protein kinase (MAPK) inhibitor PD98059 and p21(Cip/WAF1) short interfering RNA (siRNA). We determined that protein arginine methyltransferase 7 (PRMT7) is responsible for the methylation, and that PRMT5 acts as a coordinator. Collectively, we demonstrated that eEF2, a key factor involved in protein translational elongation is symmetrically arginine-methylated in a reversible manner, being regulated by bFGF through MAPK signaling pathway.
Animals ; Arginine ; Cell Dedifferentiation ; Cyclin-Dependent Kinase Inhibitor p21/genetics/metabolism ; Elongation Factor 2 Kinase/*metabolism ; Fibroblast Growth Factor 2/*metabolism ; Fibroblasts/*metabolism/pathology ; Flavonoids/pharmacology ; MAP Kinase Signaling System/drug effects/genetics ; Methylation ; Mice ; Mitogen-Activated Protein Kinases/antagonists & inhibitors ; Myofibroblasts/pathology ; NIH 3T3 Cells ; Protein Methyltransferases/*metabolism ; Protein-Arginine N-Methyltransferases/*metabolism ; RNA, Small Interfering/genetics

OBJECTIVETo observe the expression of protein arginine N-methyltransferase (PRMT) genes in the lung and spleen of E3 rats with acute asthma.

METHODSE3 rats with ovalbumin-induced pulmonary inflammation were divided into two groups (n=10), and the validity of the acute asthma model was evaluated by histological observation with HE and PAS staining and by measurement of NO production. Semi-quantitative RT-PCR was employed to detect the expressions of PRMT1-PRMT6 genes in the lung and spleen tissues of the rats.

RESULTSIn the lung tissue of the asthmatic rats, the gene expressions of PRMT1 (P<0.01), PRMT2 (P<0.01), PRMT3 (P<0.05) and PRMT5 (P<0.05) were significantly increased, but the expression of PRMT4 gene (P<0.05) was significantly decreased as compared with those in the control tissue. In the spleen tissue of the asthmatic rats, the expressions of PRMT2 (P<0.05) and PRMT5 genes (P<0.05) showed a significant increase as compared with those in the control rat tissue.

CONCLUSIONThe gene expressions of PRMTs vary significantly between asthmatic rats and control rats, suggesting that PRMTs play an important role in the post-translational modification process of asthma-related genes.

Acute Disease ; Animals ; Asthma ; enzymology ; Female ; Male ; Protein Processing, Post-Translational ; Protein-Arginine N-Methyltransferases ; classification ; genetics ; metabolism ; Random Allocation ; Rats ; Rats, Inbred Strains

OBJECTIVETo explore the role of BM2 protein in the life cycle of influenza B virus.

METHODSThe authors screened human kidney MATCHMAKER cDNA library for new binding partners of BM2 of influenza B virus by using the yeast two hybrid system with truncated BM2 (26-109 aa) as the bait.

RESULTSSix positive plasmids encoding N-acetylneuraminate pyruvate lyase, angiopoietin 3, zinc finger protein 251, ribosomal protein S20, protein arginine N-methyltransferase 1 variant 1 (PRMT) and transcription factor-like 1 (TCFL1) were obtained.

CONCLUSIONThe results suggest that BM2 may play an important role in the life cycle of influenza B virus.

Angiopoietin-like Proteins ; Angiopoietins ; genetics ; metabolism ; DNA-Binding Proteins ; genetics ; metabolism ; Gene Library ; Humans ; Influenza B virus ; genetics ; metabolism ; Kidney ; metabolism ; Oxo-Acid-Lyases ; genetics ; metabolism ; Plasmids ; genetics ; Protein Binding ; Protein-Arginine N-Methyltransferases ; genetics ; metabolism ; Repressor Proteins ; genetics ; metabolism ; Ribosomal Proteins ; genetics ; metabolism ; Transcription Factors ; genetics ; metabolism ; Two-Hybrid System Techniques ; Viral Proteins ; genetics ; metabolism ; Zinc Fingers ; genetics