Krüppel-like factor 5 (KLF5) is an oncogenic factor that is highly expressed in basal-like breast cancer (BLBC) and promotes cell proliferation, survival, migration, stemness, and tumor growth; ...however, its posttranslational modifications are poorly defined. Protein arginine methyltransferase 5 (PRMT5) is also an oncogene implicated in various carcinomas, including breast cancer. In this study, we found that PRMT5 interacts with KLF5 and catalyzes the di-methylation of KLF5 at Arginine 57 (R57) in a methyltransferase activity-dependent manner in BLBC cells. Depletion or pharmaceutical inhibition (using PJ-68) of PRMT5 decreased the expression of KLF5 and its downstream target genes in vitro and in vivo. PRMT5-induced KLF5R57me2 antagonizes GSK3β-mediated KLF5 phosphorylation and subsequently Fbw7-mediated KLF5 ubiquitination and coupled degradation. Functionally, PRMT5 promotes breast cancer stem cell maintenance and proliferation, at least partially, by stabilizing KLF5. PRMT5 and KLF5 protein levels were positively correlated in clinical BLBCs. Taken together, PRMT5 methylates KLF5 to prevent its phosphorylation, ubiquitination, and degradation, and thus promotes breast cancer stem cell maintenance and proliferation. These findings suggest that PRMT5 is a potential therapeutic target for BLBC.
The methyltransferase like 3 (METTL3) has been generally recognized as a nuclear protein bearing oncogenic properties. We find predominantly cytoplasmic METTL3 expression inversely correlates with ...node metastasis in human cancers. It remains unclear if nuclear METTL3 is functionally distinct from cytosolic METTL3 in driving tumorigenesis and, if any, how tumor cells sense oncogenic insults to coordinate METTL3 functions within these intracellular compartments. Here, we report an acetylation-dependent regulation of METTL3 localization that impacts on metastatic dissemination. We identify an IL-6-dependent positive feedback axis to facilitate nuclear METTL3 functions, eliciting breast cancer metastasis. IL-6, whose mRNA transcript is subjected to METTL3-mediated m
A modification, promotes METTL3 deacetylation and nuclear translocation, thereby inducing global m
A abundance. This deacetylation-mediated nuclear shift of METTL3 can be counterbalanced by SIRT1 inhibition, a process that is further enforced by aspirin treatment, leading to ablated lung metastasis via impaired m
A methylation. Intriguingly, acetylation-mimetic METTL3 mutant reconstitution results in enhanced translation and compromised metastatic potential. Our study identifies an acetylation-dependent regulatory mechanism determining the subcellular localization of METTL3, which may provide mechanistic clues for developing therapeutic strategies to combat breast cancer metastasis.
∆Np63α is a key transcription factor overexpressed in types of squamous cell carcinomas (SCCs), which represses epithelial–mesenchymal transition (EMT) and cell migration. In this study, we found ...that CDK1 phosphorylates ∆Np63α at the T123 site, impairing its affinity to the target promoters of its downstream genes and its regulation of them in turn. Database analysis revealed that CDK1 is overexpressed in head and neck squamous cell carcinomas (HNSCCs), especially the metastatic HNSCCs, and is negatively correlated with overall survival. We further found that CDK1 promotes the EMT and migration of HNSCC cells by inhibiting ∆Np63α. Altogether, our study identified CDK1 as a novel regulator of ΔNp63α, which can modulate EMT and cell migration in HNSCCs. Our findings will help to elucidate the migration mechanism of HNSCC cells.
Bone metastatic cancer-secreted extracellular factors are capable of modifying the bone microenvironment through interacting with bone cells, including osteoblasts. Reticulum ribosome-binding protein ...1 (RRBP1) is substantially expressed in certain bone metastatic cancer cells. This study was undertaken to determine whether RRBP1 from bone metastatic cancer cells affects the osteoblastic phenotype expression. Breast and prostate cancer cells, MDA-MB-231 and PC3, were cultured, respectively, followed by collecting conditioned mediums (CMs) and identifying the abundance of RRBP1 in CMs using LC-MS/MS. MC3T3-E1 cells were cultured with a mixed medium (including CMs from sh
-transduced two-type cancer cells) with or without endoplasmic reticulum (ER) stress inhibitor 4-PBA, followed by measuring the levels of osteoblastic phenotype expression and biomarkers of ER stress using western blotting, qPCR, and ARS staining, respectively. Similar experiments were performed in sh
-transduced MC3T3-E1 cells cultured with a mixed medium (including CMs from the two-type cancer cells). Bone formation parameters were measured in the tibia of nude mice injected with sh
-transduced two-type cancer cells using micro-CT analysis. These results showed that RRBP1 is the sole shared high-abundance protein in CMs from the two-type cancer cells, involving osteoblast differentiation. CMs from sh
-transduced two-type cells boosted the osteoblastic phenotype expression partially through increasing ER stress. CMs from the two-type cancer cells partially offset the similar alterations induced by sh
in MC3T3-E1 cells. Injection with sh
-transduced two-type cells ameliorated the bone lesions in nude mice. Therefore, RRBP1 depletion of bone metastatic cancer enhanced the osteoblastic phenotype expression, suggesting a role of RRBP1 in the bone microenvironment.
In diabetes mellitus, death of β cell in the pancreas occurs throughout the development of the disease, with loss of insulin production. The maintenance of β cell number is essential to maintaining ...normoglycemia. SNAPIN has been found to regulate insulin secretion, but whether it induces β cell proliferation remains to be elucidated. This study aimed to explore the physiological roles of SNAPIN in β cell proliferation. SNAPIN expression increases with the age of mice and SNAPIN is down-regulated in diabetes. KEGG pathway and GO analysis showed that SNAPIN- interacting proteins were enriched in cell cycle regulation. B cell cycle was arrested in the S phase, and cell proliferation was inhibited after SNAPIN knockdown. The expression of CDK2, CDK4 and CCND1 proteins in the S phase of the cell cycle were reduced after SNAPIN knockdown, whereas they were increased after overexpression of SNAPIN. In addition, insulin protein and mRNA levels also increased or decreased after SNAPIN knockdown or overexpression, respectively. Conclusions: Our data indicate that SNAPIN mediates β cells proliferation and insulin secretion, and provide evidences that SNAPIN might be a pharmacotherapeutic target for diabetes mellitus.
Polymer-textile liner composites have potential applications in aerospace applications for reducing the abrasion damage of moving parts during operation owing to their self-lubrication, light weight, ...and high loading capacity. Herein, Au nanoparticles (AuNPs) are successfully loaded into the lumen of halloysite nanotubes (HNTs) to construct an HNTs-Au peasecod core-shell nanosystem to optimize the wear resistance of phenolic resin-based poly(p-phenylene benzobisoxazole) (PBO)/polytetrafluoroethylene (PTFE) textile composites. Transmission electron microscope (TEM) characterization reveals that the AuNPs are well-dispersed inside the HNTs, with an average diameter of 6–9 nm. The anti-wear performance of the HNTs and Au-reinforced PBO/PTFE composites is evaluated using a pin-on-disk friction tester at 100 MPa. Evidently, the addition of HNTs-Au induces a 27.9% decrease in the wear rate of the composites. Possible anti-wear mechanisms are proposed based on the analyzed results of the worn surface morphology and the cross-section of the tribofilm obtained by focused ion beam transmission electron microscopy.
OBJECTIVES This study examined the development of Chinese pre-service physical education teachers’ technical skill, tactical understanding, game performance (common content knowledge - CCK), and ...specialized content knowledge (SCK) during a badminton course incorporating Play Practice instruction.METHODS Participants were 36 pre-service teachers (31 males, 5 females: age 21 ± 1.0) majoring in physical education at a university in central China. The students completed a 24 lesson course after a 16 weeks semester. A typical lesson (90 minutes) included a 10-minute warm-up, followed by instruction in two or three technical skills or tactics for 50-55 minutes. The final 25-minutes included the Play Practice aspect of the lesson - a specific game-based challenge to reinforce a technical or tactical aspect of badminton play. The challenge included the three typical pedagogies of Play Practice: focusing, shaping, and enhancing. The French clear test, tactical understanding in badminton, Game Performance Assessment Instrument (GPAI), and student-generated content maps were used to respectively monitor changes in technical skills, tactical understanding, game performance, and specialized content knowledge before and after the course. Parametric statistics were used to compare student outcomes.RESULTS Statistically significant differences were found on all measures from pre- to post-test, with all showing large effect sizes. In particular, over 75% of students achieved the benchmark depth of SCK following the course.CONCLUSIONS The inclusion of Play Practice within a sport instruction course can contribute to various elements that are needed to promote the CCK and SCK of pre-service physical education students.
PIWI-interacting RNAs (piRNAs) are a class of noncoding RNAs originally reported in the reproductive system of mammals and later found to be aberrantly expressed in tumors. However, the function and ...mechanism of piRNAs in testicular cancer are not very clear.
The expression level and distribution of piR-36249 were detected by RT-qPCR and immunofluorescence staining assay. Testicular cancer cell (NT2) progression was measured by CCK8 assay, colony formation assay and wound healing assay. Cell apoptosis was assessed by flow cytometry and western blot. RNA sequencing and dual-luciferase reporter assay were conducted to identify the potential targets of piR-36249. The relationship between piR-36249 and OAS2 or DHX36 was confirmed using overexpression assay, knockdown assay, pull-down assay and RIP assay.
piR-36249 is significantly downregulated in testicular cancer tissues compared to tumor-adjacent tissues. Functional studies demonstrate that piR-36249 inhibits testicular cancer cell proliferation, migration and activates the cell apoptosis pathway. Mechanically, we identify that piR-36249 binds to the 3′UTR of 2′-5′-oligoadenylate synthetase 2 (OAS2) mRNA. OAS2 has been shown in the literature to be a tumor suppressor modulating the occurrence and development of some tumors. Here, we show that OAS2 knockdown also promotes testicular cancer cell proliferation and migration. Furthermore, piR-36249 interacts with DHX36, which has been reported to promote translation. DHX36 can also bind to OAS2 mRNA, and knockdown of DHX36 increases OAS2 mRNA but downregulates its protein, indicating the enhancing effect of DHX36 on OAS2 protein expression.
All these data suggest that piR-36249, together with DHX36, functions in inhibiting the malignant phenotype of testicular cancer cells by upregulating OAS2 protein and that piR-36249 may be used as a suppressor factor to regulate the development of testicular cancer.
Common content knowledge (CCK) includes the knowledge of (a) rules, safety, and etiquette, (b) techniques, and (c) tactics of movement forms (e.g., sports, dance and yoga; Ward, 2009) and has been ...established as critical knowledge for teachers to provide quality instruction. The purpose of this study was to evaluate the validity and reliability of a volleyball CCK test of preservice teachers in Japan. The test was developed using three steps: (a) content experts developed the questions, (b) ten experienced secondary school physical education teachers established face and content validity, and (c) the test was pilot tested with eight preservice teachers to secure concurrent validity. Following this, the test was given to 126 physical education preservice teachers. Data were analyzed using Rasch modeling (Rasch, 1980). The data fit the model for 29 of 30 questions. The analysis provides evidence to support the validity and reliability of the volleyball CCK test for Japanese physical education preservice teachers. The test can be confidently used to assess the knowledge of preservice teachers and the effectiveness of teacher education programs.
The analysis of nanoparticles’ biocompatibility and immunogenicity is mostly performed under a healthy condition. However, more clinically relevant evaluation conducted under pathological condition ...is less known. Here, the immunogenicity and bio–nano interactions of porous silicon nanoparticles (PSi NPs) are evaluated in an acute liver inflammation mice model. Interestingly, a new mechanism in which PSi NPs can remit the hepatocellular damage and inflammation activation in a surface dependent manner through protein corona formation, which perturbs the inflammation by capturing the pro‐inflammatory signaling proteins that are inordinately excreted or exposed under pathological condition, is found. This signal sequestration further attenuates the nuclear factor κB pathway activation and cytokines production from macrophages. Hence, the study proposes a potential mechanism for elucidating the altered immunogenicity of nanomaterials under pathological conditions, which might further offer insights to establish harmonized standards for assessing the biosafety of biomaterials in a disease‐specific or personalized manner.
The inflammation attenuation capability of porous silicon nanoparticles (PSi NPs) under an acute liver inflammation condition is positively correlated with the protein corona formation process. The detailed composition of protein corona composition of each type of PSi NPs is identified and confirmed by both proteomic and R‐language analyses, highlighting the role of PSi NPs in the prognosis of the disease.
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