ABSTRACT
The microcarrier system offers an attractive method for cellular amplification and phenotype enhancement in the field of bone tissue engineering. However, it remains a challenge to fabricate porous microcarriers with osteoinductive activity for speedy and high-quality osseointegration in regeneration of serious complication of bone fracture, like nonunion. Here, we present a facile method for the first time manufacture microcarriers with osteogenic effects and properties based on well controlled and long-term Sr2+ release. At first, strontium-substituted hydroxyapatite was prepared (Sr-HA) and a novel Sr-HA-graft-poly(γ-benzyl-l-glutamate) (Sr-HA-PBLG) nanocomposite was synthesized. Then, the microcarriers with highly interconnected macropores were fabricated by a double emulsion method, which allowed cells to adhere and proliferate and secrete extracellular matrix. Besides, the microcarriers with a relatively uniform diameter of 271.5 ± 45.0 µm are feasible for injection. The Sr-HA-PBLG microcarriers efficiently promoted osteogenic gene expression in vitro. With injection of the Sr-HA-PBLG microcarriers loading adipose derived stem cells (ADSCs) into the nonunion sites, bone regeneration was observed at 8 weeks after injection in a mice model.
Subject(s)
Durapatite/administration & dosage , Nanocomposites/administration & dosage , Osteogenesis/drug effects , Tissue Engineering , Animals , Bone Regeneration/drug effects , Cell Adhesion/drug effects , Cell Differentiation/drug effects , Cell Proliferation/drug effects , Durapatite/chemistry , Extracellular Matrix/drug effects , Gene Expression Regulation, Developmental/drug effects , Mice , Nanocomposites/chemistry , Polyglutamic Acid/administration & dosage , Polyglutamic Acid/analogs & derivatives , Polyglutamic Acid/chemistryABSTRACT
Self-healing polymeric hydrogels have the capability to recover their structures and functionalities upon injury, which are extremely attractive in emerging biomedical applications. This research reports a new kind of self-healing polypeptide hydrogels based on self-assembly between cholesterol (Chol)-modified triblock poly(L-glutamic acid)-block-poly(ethylene glycol)-block-poly(L-glutamic acid) ((PLGA-b-PEG-b-PLGA)-g-Chol) and ß-cyclodextrin (ß-CD)-modified poly(L-glutamic acid) (PLGA-g-ß-CD). The hydrogel formation relied on the host and guest linkage between ß-CD and Chol. This study demonstrates the influences of polymer concentration and ß-CD/Chol molar ratio on viscoelastic behavior of the hydrogels. The results showed that storage modulus was highest at polymer concentration of 15% w/v and ß-CD/Chol molar ratio of 1:1. The effect of the PLGA molecular weight in (PLGA-b-PEG-b-PLGA)-g-Chol on viscoelastic behavior, mechanical properties and in vitro degradation of the supramolecular hydrogels was also studied. The hydrogels showed outstanding self-healing capability and good cytocompatibility. The multilayer structure was constructed using hydrogels with self-healing ability. The developed hydrogels provide a fascinating glimpse for the applications in tissue engineering.
Subject(s)
Glutamic Acid/chemistry , Hydrogels/chemistry , Biocompatible Materials/chemistry , Humans , Molecular Weight , Polyesters/chemistry , Polyethylene Glycols/chemistry , Tissue Engineering , Tissue Scaffolds , beta-Cyclodextrins/chemistryABSTRACT
Previous studies have shown that promoter hypermethylation plays a key role in DLC-1 inactivation in nasopharyngeal carcinoma (NPC). However, DLC-1 mutation in NPC has not been reported, and there remain some discrepancies in methods and results between different groups. Here, we examined the mRNA and protein expression of DLC-1 in chronic nasopharyngitis (CN) and NPC tissues by reverse transcription-polymerase chain reaction/qPCR and immunohistochemistry, respectively. DLC-1 mRNA was undetectable in all the seven widely used NPC cell lines and absent or significantly down-regulated in 70% of NPC tissues. DLC-1 protein level was reduced in 74.3% of NPCs when compared with CN tissues, and significantly lower in NPC samples at advanced clinical stages than that at early stages. Then, we purified the same batch of specimens by microdissection and analyzed the possible mechanisms of DLC-1 downregulation with mutation and allelic loss analysis, methylation-specific PCR and bisulfite genomic sequencing. Only one mutation was detected at codon 693 of exon 8 in 3.3% of NPCs and five single nucleotide polymorphisms (SNPs) were identified. Loss of DLC-1 was detected in 23.3% of NPC tissues. The 100% of NPC cell lines, 80% of primary NPC and 22.2% of CN tissues showed methylation in DLC-1 promoter, while DLC-1 expression was recovered in seven NPC cell lines after 5-aza-dC treatment. Patched methylation assay confirmed that promoter methylation could repress DLC-1 expression. This report demonstrates that DLC-1 is negatively associated with NPC carcinogenesis, and promoter hypermethylation along with loss of heterozygosity, but not mutation, contributes to inactivation of DLC-1 in NPC.
Subject(s)
DNA Methylation/genetics , GTPase-Activating Proteins/genetics , Loss of Heterozygosity , Nasopharyngeal Neoplasms/genetics , Promoter Regions, Genetic/genetics , Tumor Suppressor Proteins/genetics , Adolescent , Adult , Aged , Base Sequence , Carcinoma , Down-Regulation , Female , GTPase-Activating Proteins/biosynthesis , Gene Expression Regulation, Neoplastic , Humans , Male , Middle Aged , Mutation , Nasopharyngeal Carcinoma , Nasopharyngitis/genetics , Polymorphism, Single Nucleotide , RNA, Messenger/biosynthesis , Sequence Analysis, DNA , Tumor Suppressor Proteins/biosynthesis , Young AdultABSTRACT
Objective: To investigate the effects of perioperative general anesthesia (GA) and spinal anesthesia (SA) on postoperative rehabilitation in elderly patients with lower limb surgery. Methods: This retrospective propensity score-matched cohort study included patients aged 65 years or older who underwent lower limb surgery between January 1, 2020, and May 31, 2023. The GA and SA were selected at the request of the orthopedic surgeon, patient, and their family members. The main outcomes included the incidence of the patient's inability to self-care at discharge, postoperative complications including pulmonary infection, thrombus of lower extremity veins, infection of incisional wound and delirium, length of hospital stay, and incidence of severe pain in the first 2 days postoperatively. Results: In total, 697 patients met the inclusion criteria, and 456 were included in the final analysis after propensity score matching. In the GA and SA groups, 27 (11.84%) and 26 (11.40%) patients, respectively, could not care for themselves at discharge. The incidence rates did not differ between the groups (p = 0.884). In contrast, the incidence of postoperative complications (GA: 10.53% and SA: 4.39%; p = 0.013) and the length of hospital stay (GA: 16.92 ± 10.65 days and SA: 12.75 ± 9.15 days; p < 0.001) significantly differed between the groups. Conclusion: The choice of anesthesia is independent of the loss of postoperative self-care ability in older patients (>65 years) and is not a key factor affecting postoperative rehabilitation after lower limb surgery. However, compared with GA, SA reduces the incidence of postoperative complications and a prolonged hospital stay. Thus, SA as the primary anesthetic method is a protective factor against a prolonged hospital stay.
ABSTRACT
ESRG (embryonic stem cell related gene, also known as HESRG), is a novel human gene first cloned and identified by our group with microarray analysis. Interestingly, it is expressed specifically in undifferentiated human embryonic stem cells (hESCs), while its expression pattern and its role in hESCs remain unclear. Here, full-length 3151nt ESRG cDNA was further identified by RNA ligase mediated rapid amplification of cDNA ends (RLM-RACE) technique. Meanwhile, an alternatively splicing ESRG transcript (ESRG-B) of 2837nt in length was also found. Surprisingly, bioinformatics analyses showed that the open reading frames (ORFs) of ESRG and ESRG-B were identical. Both of them consist of 669nt and encode a 222aa protein with a predicted molecular size of 24 kDa. The ESRG protein was located in the nuclei of hESCs as demonstrated by immunocytochemical staining and Western blotting using ESRG specific antibody generated by us. In contrast, ESRG located in the cytoplasm of COS7 cells when it was forced to be expressed in these cells by gene transfection strategy, suggesting there may be some special proteins present only in hESCs which can help ESRG protein transport into the nuclei of hESCs. By spatial expression analysis, we further discovered that ESRG only expressed in the ovary tissue and hESCs instead of other tissues or cell lines. Our current data provide us with an important basis for conducting further studies on the functions and regulatory mechanisms underlying the role of ESRG in hESCs.
Subject(s)
Cell Nucleus/metabolism , Embryonic Stem Cells/metabolism , Gene Expression Profiling , Proteins/genetics , Proteins/metabolism , Alternative Splicing , Amino Acid Sequence , Animals , Base Sequence , Blotting, Western , COS Cells , Cell Line , Chlorocebus aethiops , Cytoplasm/metabolism , Embryonic Stem Cells/cytology , Female , Fetus/metabolism , Humans , Mice , Microscopy, Fluorescence , Molecular Sequence Data , Ovary/embryology , Ovary/metabolism , Protein Isoforms/genetics , Protein Isoforms/metabolism , RNA, Long Noncoding , Reverse Transcriptase Polymerase Chain ReactionABSTRACT
A new generation of osteochondral integrated scaffolds is needed for articular osteochondral regeneration, which can not only facilitate the accurate construction of osteochondral scaffolds in a minimally invasive manner but also firmly combine the subchondral bone layer and cartilage layer. Herein, an osteochondral integrated hydrogel scaffold was constructed by the poly(L-glutamic acid) (PLGA) based self-healing hydrogels with phenylboronate ester (PBE) as the dynamic cross-linking. The bone layer self-healing hydrogel (hydrogel O-S) was prepared by physically blending nanohydroxyapatite into the self-healing hydrogel PLGA-PBE-S, which was fabricated by 3-aminophenylboronic acid/glycidyl methacrylate-modified PLGA (PLGA-GMA-PBA) and 3-amino-1,2-propanediol/N-(2-aminoethyl) acrylamide-modified PLGA (PLGA-ADE-AP). The cartilage layer self-healing hydrogel (hydrogel C-S) was prepared by PLGA-GMA-APBA and glucosamine- modified PLGA-ADE-AP (PLGA-ADE-AP-G). Excellent injectability and self-healing profiles of hydrogel O-S and C-S were observed, the self-healing efficiencies were 97.02% ± 1.06% and 99.06% ± 0.57%, respectively. Based on the injectability and spontaneous healing on the interfaces of hydrogel O-S and C-S, the osteochondral hydrogel (hydrogel OC) was conveniently constructed in a minimally invasive manner. In addition,in situphotocrosslinking was used to enhance the mechanical strength and stability of the osteochondral hydrogel. The osteochondral hydrogels exhibited good biodegradability and biocompatibility. The osteogenic differentiation genes BMP-2, ALPL, BGLAP and COL I of adipose-derived stem cells (ASCs) in the bone layer of the osteochondral hydrogel were significantly expressed, and the chondrogenic differentiation genes SOX9, aggrecan and COL II of ASCs in the cartilage layer of the osteochondral hydrogel were obviously upregulated after 14 d of induction. The osteochondral hydrogels could effectively promote repair of osteochondral defects after 3 months post-surgery.
Subject(s)
Hydrogels , Tissue Engineering , Hydrogels/chemistry , Osteogenesis , Amino Acids , Tissue Scaffolds/chemistryABSTRACT
PURPOSE: To explore the effect of sodium alginate-g-deferoxamine/chitosan (SA-g-DFO/CS) microspheres on proliferation and osteogenic differentiation of rat bone mesenchymal stem cells (BMSCs). METHODS: A kind of SA-g-DFO/CS microsphere was developed through electrostatic interaction between porous chitosan microspheres and sodium alginate chemically grafted on the surface of DFO. Its morphology, porosity rate, pore size and sustained release of DFO in vitro were examined. Rat BMSCs were isolated and co-cultured with microspheres in osteogenic differentiation medium. MTT assay was used to study the influence of cell proliferation, and Calcein-AM/PI staining was used to observe the cell viability. Alkaline phosphatase (ALP) activity assay was conducted. PCR was used to detect the expression of genes related to angiogenesis and osteogenesis. Statistical analysis was performed using SPSS 22.0 software package. RESULTS: The SA-g-DFO/CS porous microspheres were successfully prepared with a sustained re6lease of DFO. Compared with SA/CS microspheres, the SA-g-DFO/CS microspheres were conducive to cell proliferation and differentiation, with the increases in expression level of ALP, related angiogenesis genes HIF-1α, VEGF and osteogenesis genes COLI, OCN. CONCLUSIONS: The SA-g-DFO/CS porous microspheres can provide a new choice for the development of alveolar bone regeneration.
Subject(s)
Chitosan , Mesenchymal Stem Cells , Rats , Animals , Osteogenesis/genetics , Deferoxamine/pharmacology , Deferoxamine/metabolism , Microspheres , Cell Differentiation , Mesenchymal Stem Cells/metabolism , Alginates/pharmacology , Cells, CulturedABSTRACT
The lack of interconnected macro-porous structure of most injectable hydrogels lead to poor cell and tissue infiltration. Herein, we present the fabrication of injectable macro-porous hydrogels based on "smashed gels recombination" strategy. Chitosan/polyethylene glycol-silicotungstic acid (CS/PEG-SiW) double-network hydrogels were prepared via dual dynamic interactions. The bulk CS/PEG-SiW hydrogels were then smashed into micro-hydrogels with average sizes ranging from 47.6 to 63.8 µm by mechanical fragmentation. The CS/PEG-SiW micro-hydrogels could be continuously injected and rapidly recombined into a stable porous hydrogel based on the dual dynamic interactions between micro-hydrogels. The average pore size of the recombined porous CS/PEG-SiW hydrogels ranged from 52 to 184 µm. The storage modulus, compress modulus and maximum compressive strain of the recombined porous CS/PEG-SiW1.0 hydrogels reached about 47.2 %, 28.2 % and 127.6 % of the values for their corresponding bulk hydrogels, respectively. The recombined porous hydrogels were cytocompatible and could effectively support proliferation and chondrogenic differentiation of bone marrow mesenchymal stem cells (BMSCs). In a rat cartilage defect model, recombined porous CS/PEG-SiW hydrogels could promote cartilage regeneration. Hematoxylin and eosin (H&E), Safranin-O/Fast green and immunohistochemical staining confirmed the accumulation of glycosaminoglycans (GAG) and type II collagen (Col II) in regenerated cartilage.
Subject(s)
Chitosan , Rats , Animals , Chitosan/chemistry , Tissue Engineering , Hydrogels/chemistry , Polyethylene Glycols/pharmacology , Porosity , Cartilage , Biocompatible Materials/pharmacology , Chondrogenesis , Recombination, GeneticABSTRACT
Cartilage injury is a very common joint disease, and cartilage repair is a great challenge in clinical treatment due to the specific structure of cartilage tissue and its microenvironment in vivo. The injectable self-healing hydrogel is a very promising candidate as a cartilage repair material because of its special network structure, high water retention and self-healing properties. In this work, a self-healing hydrogel cross-linked by host-guest interaction between cyclodextrin and cholic acid was developed. The host material was composed of ß-cyclodextrin and 2-hydroxyethyl methacrylate-modified poly(l-glutamic acid) (P(LGA-co-GM-co-GC)), while the guest material was chitosan modified by cholic acid, glycidyl methacrylate, and (2,3-epoxypropyl)trimethylammonium chloride (EPTAC) (QCSG-CA). The host-guest interaction self-healing hydrogels, named as HG hydrogels (HG gel), exhibited excellent injectability and self-healable property, and the self-healing efficiency was greater than 90%. Furthermore, in order to enhance the mechanical properties and slow down the degradation of the HG gel in vivo, the second network was constructed by photo-cross-linking in situ. Biocompatibility tests showed that the enhanced multi-interaction hydrogel (MI gel) was extremely suitable for cartilage tissue engineering both in vitro and in vivo. In addition, the adipose derived stem cells (ASCs) in MI gel were able to differentiate cartilage effectively in vitro in the presence of inducing agents. Subsequently, the MI gel without ASCs was transplanted into rat cartilage defects in vivo for the regeneration of cartilage. After 3 months postimplantation, new cartilage tissue was successfully regenerated in a rat cartilage defect. All results indicated that the injectable self-healing host-guest hydrogels have important potential applications in cartilage injury repair.
Subject(s)
Chitosan , Rats , Animals , Hydrogels/pharmacology , Hydrogels/chemistry , Amino Acids/pharmacology , Cartilage , RegenerationABSTRACT
The novel stem cell-related gene, HESRG, was first identified by our group, and its expression pattern in human tumors remains unknown. In this study, we used RT-PCR to systematically investigate the expression of HESRG in various types of intracranial tumors and found that HESRG was expressed only in germinoma and embryonal carcinoma, but hardly at all in other types of brain tumors. Real-time PCR results further confirmed this expression pattern. Subsequently, we tested 134 intracranial non-germ cell tumors and 64 intracranial germ cell tumors by immunohistochemistry. Our results showed that HESRG was expressed strongly and diffusively in the nuclei of tumor cells in intracranial germinoma and embryonal carcinoma as well as in human embryonic stem cells. No positive staining signal was observed in any other type of intracranial tumors. In germinomas, 25 of 31 showed intensive (3+) expression, four cases showed moderate (2+) immunostaining and the remaining 2 cases showed weak (1+) immunostaining. In embryonal carcinoma, 6 of 9 showed intensive (3+) immunostaining and 3 of 9 showed moderate (2+) immunostaining. These results suggest that HESRG is a novel, sensitive and specific biomarker for intracranial germinoma and embryonal carcinoma.
Subject(s)
Biomarkers, Tumor/analysis , Brain Neoplasms/metabolism , Carcinoma, Embryonal/metabolism , Germinoma/metabolism , Proteins/metabolism , Brain Neoplasms/genetics , Brain Neoplasms/pathology , Carcinoma, Embryonal/genetics , Carcinoma, Embryonal/pathology , Germinoma/genetics , Germinoma/pathology , Humans , Immunohistochemistry , Proteins/genetics , RNA, Long Noncoding , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain ReactionABSTRACT
OCT4 expresses variably in primary intracranial germinomas. In this study, we tested our hypothesis that such variation of OCT4 is predictive of outcome in primary intracranial germinomas. Thirty-one histologically identified CNS germinoma patients were enrolled in our study. We collected medical data, immunohistochemically evaluated the OCT4 expression level, and followed up all patients from April 2001 to May 2010. We found that 7 of the 31 patients expressed OCT4 weakly, 11 expressed OCT4 moderately, and 13 expressed OCT4 strongly. No significant correlation between the OCT4 expression level and clinicopathological characteristics was observed. WV-CS combined treatment modality showed a better 5-year progression-free survival (PFS) rate than other treatment modalities and a low expression level of OCT4 showed a significantly better 5-year PFS. In both the WV-CS combined treatment modality and other treatments modality group, patients received a better 5-year PFS and had a lower level of OCT4 expression. As a result, we suggest OCT4 as a probable prognostic marker for intracranial germinoma.
Subject(s)
Biomarkers, Tumor/metabolism , Brain Neoplasms/metabolism , Germinoma/metabolism , Octamer Transcription Factor-3/metabolism , Adolescent , Adult , Brain Neoplasms/mortality , Brain Neoplasms/therapy , Child , Combined Modality Therapy , Disease-Free Survival , Female , Germinoma/mortality , Germinoma/therapy , Humans , Immunohistochemistry , Kaplan-Meier Estimate , Magnetic Resonance Imaging , Male , Neoplasm Recurrence, Local/metabolism , Neoplasm Recurrence, Local/mortality , Prognosis , Retrospective Studies , Young AdultABSTRACT
Microtissues exhibit great advantages in injecting with minimum invasiveness, mimicking natural tissues, and promoting tissue regeneration. However, very few studies have focused on the construction of osteochondral microtissues that could simultaneously support hyaline-like cartilage and bone tissue regeneration. In this study, chondral microtissues that could favor the formation of hyaline-like cartilages and subchondral bone microtissues that could repair subchondral defects to support the neo-generated cartilages were successfully constructed for osteochondral tissue engineering. For chondral repair, the developed chondral microgels with high porosity and hydrophilicity could make cells spherical, favor the formation of cell aggregates, and show an excellent differentiation effect toward hyaline-like cartilage, thus contributing to the production of chondral microtissues. For subchondral bone repair, the fabricated subchondral microgels realize cell adhesion and proliferation and support the osteogenic differentiation of stem cells, thus favoring the formation of subchondral bone microtissues. The injectable chondral and subchondral bone microtissues could be stably assembled by Michael addition reaction between sulfhydryl groups of microtissues and double bonds of hydrophilic macromolecular cross-linker. At 12 weeks postimplantation, osteochondral microtissues could support the reconstruction of osteochondral-like tissues. The present study provides new insight into the microtissues for repair of osteochondral tissues.
Subject(s)
Cartilage, Articular , Tissue Engineering , Bone Regeneration , Cell Differentiation , Osteogenesis , Tissue Scaffolds/chemistryABSTRACT
Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer with limited therapeutic options available. We have recently demonstrated that lovastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, suppresses TNBC cell proliferation and stemness properties in vitro and in vivo. However, the mechanisms through which lovastatin inhibits TNBC cells are not fully understood. Here, we used 1H NMR-based metabolomic profiling to investigate lovastatin-induced metabolic changes in TNBC cell line MDA-MB-231. Among the 46 metabolites identified, lactate demonstrated the highest variable importance in projection (VIP) score. Glycolysis stress test revealed that lovastatin significantly decreased the extracellular acidification rate (ECAR) in MDA-MB-231 cells. Furthermore, lovastatin treatment down-regulated the levels of glycolysis-related proteins including GLUT1, PFK1, and PKM2 in MDA-MB-231 but not non-TNBC MDA-MB-453 cells. In addition, lovastatin induced autophagy as evidenced by increased LC3 puncta formation and LC3-II/I ratio, increased AMPK phosphorylation, and decreased Akt phosphorylation. We also revealed the interaction between the glycolytic enzyme hexokinase 2 (HK2) and the mitochondrial membrane protein voltage-dependent anion channel 1 (VDAC1), an important regulator of autophagy. Further bioinformatics analysis revealed that VDAC1 was expressed at a higher level in breast cancer than normal tissues and higher level of VDAC1 predicted poorer survival outcomes in breast cancer patients. The present study suggests that lovastatin might exert anti-tumor activity by reprogramming glycolysis toward autophagy in TNBC cells through HK2-VDAC1 interaction.
ABSTRACT
Triple-negative breast cancer (TNBC) is the most aggressive subtype of breast cancer and lacks approved specific targeted therapies. One of the major reasons why TNBC is difficult to treat is the high proportion of cancer stem cells within the tumor tissue. Nucleolus is the location of ribosome biogenesis which is frequently overactivated in cancer cells and overactivation of ribosome biogenesis frequently drives the malignant transformation of cancer. Nucleolar and coiled-body phosphoprotein 1 (NOLC1) is a nucleolar protein responsible for nucleolus organization and rRNA synthesis and plays an important role in ribosome biogenesis. However, the correlation of NOLC1 expression with patient prognosis and its value as a therapeutic target have not been evaluated in TNBC. In the current study, based on bioinformatics analysis of the online databases, we found that the expression of NOLC1 was higher in breast cancer tissues than normal tissues, and NOLC1 was expressed at a higher level in TNBC than other subtypes of breast cancer. GSEA analysis revealed that stemness-related pathways were significantly enriched in breast cancer with high NOLC1 gene expression. Further analyses using gene expression profiling interactive analysis 2 (GEPIA2), tumor immune estimation resource (TIMER) and search tool for retrieval of interacting genes/proteins (STRING) demonstrated that NOLC1 was significantly associated with stemness in both all breast cancer and basal-like breast cancer/TNBC patients at both gene and protein levels. Knockdown of NOLC1 by siRNA decreased the protein level of the key stemness regulators MYC and ALDH and inhibited the sphere-forming capacity in TNBC cell line MDA-MB-231. Univariate and multivariate Cox regression analyses demonstrated that NOLC1 was an independent risk factor for overall survival in breast cancer. PrognoScan and Kaplan-Meier plotter analyses revealed that high expression of NOLC1 was associated with poor prognosis in both all breast cancer and TNBC patients. Further immunohistochemical analysis of breast cancer patient samples revealed that TNBC cells had a lower level of NOLC1 in the nucleus compared with non-TNBC cells. These findings suggest that NOLC1 is closely associated with the stemness properties of TNBC and represents a potential therapeutic target for TNBC.
ABSTRACT
The lactoferrin (LTF) gene, located at 3p21.3, behaves like a tumor suppressor gene in diverse tumors. To elucidate the exact role of LTF in NPC, we first detected its expression level in seven NPC cell lines by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR). The results showed the mRNA level of LTF was nearly undetectable in all the seven NPC cell lines, while it could be detected in chronic nasopharyngitis tissues. Subsequently, we used methylation-specific PCR (MSP), microsatellite assay, PCR-single-strand conformation polymorphism (PCR-SSCP) and sequencing methods to examine the promoter methylation, loss of heterozygosity (LOH) and gene mutation of LTF in NPC cell lines respectively. Consequently, we found that 100% (7 of 7) of NPC cell lines were methylated in LTF promoter, only one cell line (14%, 1 of 7) had LOH and gene mutation of LTF, respectively, while LTF exhibited re-expression in all cell lines after 5-aza-dC treatment, indicating promoter methylation should be the key mechanism causing LTF downregulation in NPC cell lines. Furthermore, patched methylation assay confirmed that promoter methylation could down-regulate LTF gene expression in NPC cells. Finally, we investigated the function of LTF in NPC cell lines by gene transfection. Restoration of LTF expression in NPC cells resulted in blockage of cell cycle progression, significant inhibition of cell growth and a reduced colony-formation capacity in vitro and obviously weaker tumor formation potential in vivo. In conclusion, our data indicate LTF may participate in NPC carcinogenesis as a negative effector, that is, a tumor suppressor gene.
Subject(s)
Lactoferrin/metabolism , Nasopharyngeal Neoplasms/metabolism , Animals , Base Sequence , Carcinoma , Cell Line, Tumor , Cell Proliferation , DNA Methylation , DNA Mutational Analysis , Female , G1 Phase , Humans , Lactoferrin/genetics , Loss of Heterozygosity , Male , Mice , Mice, Nude , Molecular Sequence Data , Nasopharyngeal Carcinoma , Neoplasm Transplantation , Promoter Regions, Genetic , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Transcription, Genetic , Tumor BurdenABSTRACT
Long non-coding RNA (lncRNA) differentiation antagonizing non-protein coding RNA (DANCR) participates in the development of diverse cancers. Nevertheless, the impact of DANCR on cervical cancer (CC) remains largely unknown. This study aims to explore the effects of DANCR sponging microRNA-145-3p (miR-145-3p) on CC. Expression of KLF5, DANCR, miR-145-3p, and zinc finger E-box binding homeobox 1 (ZEB1) in CC and adjacent normal tissues was determined. Human CC cell lines were, respectively, treated with silenced DANCR or miR145-3p mimic/inhibitor. Then, the viability, migration, invasion, and apoptosis of CC cells were measured. The cell growth in vivo was observed as well. Chromatin immunoprecipitation assay was performed to analyze the binding of KLF5 and DANCR promoter. Interaction among DANCR, miR-145-3p, and ZEB1 was assessed. KLF5, DANCR, and ZEB1 were upregulated but miR-145-3p was downregulated in CC tissues. KLF5 activated DANCR expression and the high DANCR expression was related to tumor staging, infiltrating muscle depth and lymphatic metastasis of CC patients. Reduced DANCR or elevated miR-145-3p repressed malignant behaviors of CC cells. The tumor diameter and weight were also repressed by DANCR silencing or miR-145-3p elevation. The effect of DANCR knockdown on CC cells could be reversed by miR-145-3p inhibitor. MiR-145-3p was targeted by DANCR and ZEB1 was targeted by miR-145-3p. KLF5-induced overexpression of DANCR promotes CC progression via suppressing miR-145-3p to target ZEB1. This study may provide potential targets for CC treatment.
Subject(s)
MicroRNAs , RNA, Long Noncoding , Uterine Cervical Neoplasms , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Female , Gene Expression Regulation, Neoplastic , Humans , Kruppel-Like Transcription Factors/genetics , Kruppel-Like Transcription Factors/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism , Uterine Cervical Neoplasms/genetics , Uterine Cervical Neoplasms/pathology , Zinc Finger E-box-Binding Homeobox 1/genetics , Zinc Finger E-box-Binding Homeobox 1/metabolismABSTRACT
Injectable hydrogels have received much attention because of the advantages of simulation of the natural extracellular matrix, microinvasive implantation, and filling and repairing of complex shape defects. Yet, for bone repair, the current injectable hydrogels have shown significant limitations such as the lack of tissue adhesion, deficiency of self-healing ability, and absence of osteogenic activity. Herein, a strategy to construct mussel-inspired bisphosphonated injectable nanocomposite hydrogels with adhesive, self-healing, and osteogenic properties is developed. The nano-hydroxyapatite/poly(l-glutamic acid)-dextran (nHA/PLGA-Dex) dually cross-linked (DC) injectable hydrogels are fabricated via Schiff base cross-linking and noncovalent nHA-BP chelation. The chelation between bisphosphonate ligands (alendronate sodium, BP) and nHA favors the uniform dispersion of the latter. Moreover, multiple adhesion ligands based on catechol motifs, BP, and aldehyde groups endow the hydrogels with good tissue adhesion. The hydrogels possess excellent biocompatibility and the introduction of BP and nHA both can effectively promote viability, proliferation, migration, and osteogenesis differentiation of MC3T3-E1 cells. The incorporation of BP groups and HA nanoparticles could also facilitate the angiogenic property of endothelial cells. The nHA/PLGA-Dex DC hydrogels exhibited considerable biocompatibility despite the presence of a certain degree of inflammatory response in the early stage. The successful healing of a rat cranial defect further proves the bone regeneration ability of nHA/PLGA-Dex DC injectable hydrogels. The developed tissue adhesive osteogenic injectable nHA/PLGA-Dex hydrogels show significant potential for bone regeneration application.
Subject(s)
Biomimetic Materials/chemistry , Bone Regeneration/drug effects , Hydrogels/chemistry , Nanocomposites/chemistry , Osteogenesis/drug effects , Tissue Scaffolds/chemistry , Adhesives/chemical synthesis , Adhesives/chemistry , Adhesives/toxicity , Alendronate/analogs & derivatives , Alendronate/toxicity , Animals , Biocompatible Materials/chemical synthesis , Biocompatible Materials/chemistry , Biocompatible Materials/toxicity , Biomimetic Materials/chemical synthesis , Biomimetic Materials/toxicity , Bone and Bones/drug effects , Cell Line , Cell Physiological Phenomena/drug effects , Dextrans/chemical synthesis , Dextrans/chemistry , Dextrans/toxicity , Durapatite/chemical synthesis , Durapatite/chemistry , Durapatite/toxicity , Female , Hydrogels/chemical synthesis , Hydrogels/toxicity , Male , Mice , Nanocomposites/toxicity , Polyglutamic Acid/chemical synthesis , Polyglutamic Acid/chemistry , Polyglutamic Acid/toxicity , Rats, Sprague-Dawley , Swine , Tissue Engineering/methodsABSTRACT
Triple-negative breast cancer (TNBC) is more aggressive and has poorer prognosis compared to other subtypes of breast cancer. Epithelial-to-mesenchymal transition (EMT) is a process in which epithelial cells transform into mesenchymal-like cells capable of migration, invasion, and metastasis. Recently, we have demonstrated that lovastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitor and a lipid-lowering drug, could inhibit stemness properties of cancer stem cells (CSCs) derived from TNBC cell in vitro and in vivo. This study is aimed at investigating whether lovastatin inhibits TNBC CSCs by inhibiting EMT and suppressing metastasis and the mechanism involved. In the present study, we found that lovastatin dysregulated lysine succinylation of cytoskeleton-associated proteins in CSCs derived from TNBC MDA-MB-231 cell. Lovastatin inhibited EMT as demonstrated by down-regulation of the protein levels of Vimentin and Twist in MDA-MB-231 CSCs in vitro and vivo and by reversal of TGF-ß1-induced morphological change in MCF10A cells. Lovastatin also inhibited the migration of MDA-MB-231 CSCs. The disruption of cytoskeleton in TNBC CSCs by lovastatin was demonstrated by the reduction of the number of pseudopodia and the relocation of F-actin cytoskeleton. Combination of lovastatin with doxorubicin synergistically inhibited liver metastasis of MDA-MB-231 CSCs. Bioinformatics analysis revealed that higher expression levels of cytoskeleton-associated genes were characteristic of TNBC and predicted survival outcomes in breast cancer patients. These data suggested that lovastatin could inhibit the EMT and metastasis of TNBC CSCs in vitro and in vivo through dysregulation of cytoskeleton-associated proteins.
ABSTRACT
Non-small cell lung cancer (NSCLC) is one of the major cancer-related causes of morbidity and mortality worldwide. Despite the progress in lung cancer treatment, there is still an urgent need to discover novel therapeutic agents for NSCLC. Natural products represent a rich source of bioactive compounds. Through a natural compound library screening assay, we found that a group of anti-insect drugs had significant inhibitory effect on the proliferation of NSCLC cells. Among the anti-insect drugs, two derivatives of artemisinin, i.e., artesunate (ART) and dihydroartemisinin (DHA), a group of well-known anti-malarial drugs, have been shown to possess selective anti-cancer properties. Mechanistically, we found that ART and DHA induced apoptosis of A549 cells as evidenced by decreased protein level of VDAC and increased caspase 3 cleavage. Furthermore, cystine/glutamate transporter (xCT), a core negative regulator of ferroptosis, was downregulated by ART and DHA. The mRNA level of transferrin receptor (TFRC), a positive regulator of ferroptosis, was upregulated by ART and DHA. ART/DHA-induced apoptosis and ferroptosis in NSCLC cells were partly reversed by N-Acetyl-L-cysteine (NAC), a ROS scavenger, and ferrostatin-1, a ferroptosis inhibitor, respectively. These results suggest that artemisinin derivatives have anti-NSCLC activity through induction of ROS-dependent apoptosis/ferroptosis. Our findings provide the experimental basis for the potential application of artemisinin derivatives as a class of novel therapeutic drugs for NSCLC.
ABSTRACT
Currently, biodegradable hydrogels are one of the most promising materials in tissue engineering. From the perspective of clinical needs, hydrogels with high strength and minimally invasive implantation are preferred for the reconstruction of load-bearing tissues. In this work, a biodegradable, high-strength, and injectable hydrogel was developed by one-step photo-cross-linking of two biomacromolecules, polyethylene glycol acrylated poly(l-glutamic acid) (PLGA-APEG) and methacrylated gellan gum (GG-MA). The hydrogels, named as PLGA/GG hydrogels, exhibited high mechanical properties. The compression stress of the hydrogels was 0.53 MPa, and the fracture energy was 7.7 ± 0.2 kJ m-2. Meanwhile, the storage modulus could reach 44.0 ± 0.6 kPa. The hydrogel precursor solution loaded with adipose-derived stem cells (ASCs) was subcutaneously injected into C57BL/6 mice and then cross-linked via in situ transdermal irradiation, which demonstrated the excellent injectability and subcutaneous gelatinization of PLGA/GG hydrogels as cell carriers. Furthermore, three-dimensional encapsulation of ASCs in hydrogels after 7, 14, and 21 days showed outstanding cytocompatibility, and the viability of ASCs was up to 84.0 ± 1.7%. The PLGA/GG hydrogels exhibited ideal behaviors of degradation, with 60 ± 5% of hydrogels degraded in phosphate buffered solution (PBS) after 11 weeks. H&E staining demonstrated that the hydrogels degraded gradually after 6 weeks and supported tissue invasion without inflammatory reactions, which indicated the laudable biodegradability of hydrogels. Hence, the biodegradable and high-strength hydrogels with well-performed injectability and biocompatibility possessed high potential applications in tissue engineering, especially in load-bearing tissue regeneration.