Ionizing irradiation is an effective treatment for malignant glioma (MG); however, a higher rate of recurrence with more aggressive phenotypes is a vital issue. Although epithelial-mesenchymal ...transition (EMT) is involved in irradiation-induced cancer progression, the role for such phenotypic transition in MG remains unknown.
To investigate the mechanism of irradiation-dependent tumor progression in MG, we performed immunohistochemistry (IHC) and qRT-PCR using primary and recurrent MG specimens, MG cell lines, and primary culture cells of MG. siRNA technique was used for MG cell lines.
In 22 cases of clinically recurrent MG, the expression of the mesenchymal markers vimentin and CD44 was found to be increased by IHC. In paired identical MG of 7 patients, the expression of collagen, MMPs, and YKL-40 were also elevated in the recurrent MGs, suggesting the The Cancer Genome Atlas-based mesenchymal subtype. Among EMT regulators, sustained elevation of Snail was observed in MG cells at 21 days after irradiation. Cells exhibited an upregulation of migration, invasion, numbers of focal adhesion, and MMP-2 production, and all of these mesenchymal features were abrogated by Snail knockdown. Intriguingly, phosphorylation of ERK1/2 and GSK-3β were increased after irradiation in a Snail-dependent manner, and TGF-β was elevated in both fibroblasts and macrophages but not in MG cells after irradiation. It was noteworthy that irradiated cells also expressed stemness features such as SOX2 expression and tumor-forming potential in vivo.
We here propose a novel concept of glial-mesenchymal transition after irradiation in which the sustained Snail expression plays an essential role.
Swainsonine (SWA), a potent inhibitor of class II α-mannosidases, is present in a number of plant species worldwide and causes severe toxicosis in livestock grazing these plants. The mechanisms ...underlying SWA-induced animal poisoning are not fully understood. In this study, we analyzed the alterations that occur in N- and free N-glycomic upon addition of SWA to HepG2 cells to understand better SWA-induced glycomic alterations. After SWA addition, we observed the appearance of SWA-specific glycomic alterations, such as unique fucosylated hybrid-type and fucosylated M5 (M5F) N-glycans, and a remarkable increase in all classes of Gn1 FNGs. Further analysis of the context of these glycomic alterations showed that (fucosylated) hybrid type N-glycans were not the precursors of these Gn1 FNGs and vice versa. Time course analysis revealed the dynamic nature of glycomic alterations upon exposure of SWA and suggested that accumulation of free N-glycans occurred earlier than that of hybrid-type N-glycans. Hybrid-type N-glycans, of which most were uniquely core fucosylated, tended to increase slowly over time, as was observed for M5F N-glycans. Inhibition of swainsonine-induced unique fucosylation of hybrid N-glycans and M5 by coaddition of 2-fluorofucose caused significant increases in paucimannose- and fucosylated paucimannose-type N-glycans, as well as paucimannose-type free N-glycans. The results not only revealed the gross glycomic alterations in HepG2 cells induced by swainsonine, but also provide information on the global interrelationships between glycomic alterations.
•SWA specific N- and free N-glycomic alterations were thoroughly extracted.•Dynamic nature of glycomic alterations upon exposure of SWA was elucidated.•Global interrelationships between glycomic alterations were revealed.•Inhibition of SWA induced N-glycans' fucosylation fluctuated FNGs' metabolism.•M5F and fucosylated hybrid N-glycans showed similar expression patterns.
Recently, we have developed a hydroxyapatite (HAp)‐hybridized double‐network (DN) hydrogel (HAp/DN gel), which can robustly bond to the bone tissue in the living body. The purpose of this study is to ...clarify whether the HAp/DN gel surface can differentiate the bone marrow‐derived mesenchymal stem cells (MSCs) to osteogenic cells. We used the MSCs which were harvested from the rabbit bone marrow and cultured on the polystyrene (PS) dish using the autogenous serum‐supplemented medium. First, we confirmed the properties of MSCs by evaluating colony forming unit capacity, expression of MSC markers using flow cytometry, and multidifferential capacity. Secondly, polymerase chain reaction analysis demonstrated that the HAp/DN gel surface significantly enhanced mRNA expression of the eight osteogenic markers (TGF‐β1, BMP‐2, Runx2, Col‐1, ALP, OPN, BSP, and OCN) in the cultured MSCs at 7 days than the PS surfaces (p < 0.0001), while the DN gel and HAp surfaces provided no or only a slight effect on the expression of these markers except for Runx2. Additionally, the alkaline phosphatase activity was significantly higher in the cells cultured on the HAp/DN gel surface than in the other three material surfaces (p < 0.0001). Thirdly, when the HAp/DN gel plug was implanted into the rabbit bone marrow, MSC marker‐positive cells were recruited in the tissue generated around the plug at 3 days, and Runx2 and OCN were highly expressed in these cells. In conclusion, this study demonstrated that the HAp/DN gel surface can differentiate the MSCs into osteogenic cells.
Accurate determination of human tumor malignancy is important for choosing efficient and safe therapies. Bioimaging technologies based on luminescent molecules are widely used to localize and ...distinguish active tumor cells. Here, we report a human cancer grade probing system (GPS) using a water-soluble and structure-changeable Eu(III) complex for the continuous detection of early human brain tumors of different malignancy grades. Time-dependent emission spectra of the Eu(III) complexes in various types of tumor cells were recorded. The radiative rate constants (k
), which depend on the geometry of the Eu(III) complex, were calculated from the emission spectra. The tendency of the k
values to vary depended on the tumor cells at different malignancy grades. Between T = 0 and T = 3 h of invasion, the k
values exhibited an increase of 4% in NHA/TS (benign grade II gliomas), 7% in NHA/TSR (malignant grade III gliomas), and 27% in NHA/TSRA (malignant grade IV gliomas). Tumor cells with high-grade malignancy exhibited a rapid upward trend in k
values. The cancer GPS employs Eu(III) emissions to provide a new diagnostic method for determining human brain tumor malignancy.
MicroRNA (miRNA) can function as tumor suppressors or oncogenes, and also as potential specific cancer biomarkers; however, there are few published studies on miRNA in synovial sarcomas, and their ...function remains unclear. We transfected the OncomiR miRNA Precursor Virus Library into synovial sarcoma Fuji cells followed by a colony formation assay to identify miRNAs to confer an aggressive tumorigenicity, and identified miR‐17‐5p from the large colonies. MiR‐17 was found to be induced by a chimeric oncoprotein SS18‐SSX specific for synovial sarcoma, and all examined cases of human synovial sarcoma expressed miR‐17, even at high levels in several cases. Overexpression of miR‐17 in synovial sarcoma cells, Fuji and HS‐SYII, increased colony forming ability in addition to cell growth, but not cell motility and invasion. Tumor volume formed in mice in vivo was significantly increased by miR‐17 overexpression with a marked increase of MIB‐1 index. According to PicTar and Miranda algorithms, which predicted CDKN1A (p21) as a putative target of miR‐17, a luciferase assay was performed and revealed that miR‐17 directly targets the 3′‐UTR of p21 mRNA. Indeed, p21 protein level was remarkably decreased by miR‐17 overexpression in a p53‐independent manner. It is noteworthy that miR‐17 succeeded in suppressing doxorubicin‐evoked higher expression of p21 and conferred the drug resistance. Meanwhile, introduction of anti‐miR‐17 in Fuji and HS‐SYII cells significantly decreased cell growth, consistent with rescued expression of p21. Taken together, miR‐17 promotes the tumor growth of synovial sarcomas by post‐transcriptional suppression of p21, which may be amenable to innovative therapeutic targeting in synovial sarcoma.
In this study, we performed cancer related miRNAs library screening to identify miRNA to confer an aggressive growth on synovial sarcoma, and identified miR‐17‐5p act as an oncogene in this tumor. Forced expression of miR‐17 in synovial sarcoma cells strikingly promoted tumorigenicity in in vivo mice by directly targeting p21CIP1/WAF1. We here found SS18‐SSX possesses an ability to induce miR‐17 that disrupt 3′UTR of p21 mRNA, resulted in an aggressive cell growth and acquired chemoresistance to doxorubicin. Hence, our findings propose miR‐17 as a candidate for p53‐independent p21 downregulation, and upregulation of p21 protein by miR‐17 depletion might exert potent effects in therapy of human synovial sarcoma.
Neural regeneration is extremely difficult to achieve. In traumatic brain injuries, the loss of brain parenchyma volume hinders neural regeneration. In this study, neuronal tissue engineering was ...performed by using electrically charged hydrogels composed of cationic and anionic monomers in a 1:1 ratio (C1A1 hydrogel), which served as an effective scaffold for the attachment of neural stem cells (NSCs). In the 3D environment of porous C1A1 hydrogels engineered by the cryogelation technique, NSCs differentiated into neuroglial cells. The C1A1 porous hydrogel was implanted into brain defects in a mouse traumatic damage model. The VEGF-immersed C1A1 porous hydrogel promoted host-derived vascular network formation together with the infiltration of macrophages/microglia and astrocytes into the gel. Furthermore, the stepwise transplantation of GFP-labeled NSCs supported differentiation towards glial and neuronal cells. Therefore, this two-step method for neural regeneration may become a new approach for therapeutic brain tissue reconstruction after brain damage in the future.
We have previously reported that an adaptor protein CRK, including CRK‐I and CRK‐II, plays essential roles in the malignant potential of various aggressive human cancers, suggesting the validity of ...targeting CRK in molecular targeted therapy of a wide range of cancers. Nevertheless, the role of CRK in human bladder cancer with marked invasion, characterized by distant metastasis and poor prognosis, remains obscure. In the present study, immunohistochemistry indicated a striking enhancement of CRK‐I/‐II, but not CRK‐like, in human bladder cancer tissues compared to normal urothelium. We established CRK‐knockdown bladder cancer cells using 5637 and UM‐UC‐3, which showed a significant decline in cell migration, invasion, and proliferation. It is noteworthy that an elimination of CRK conferred suppressed phosphorylation of c‐Met and the downstream scaffold protein Gab1 in a hepatocyte growth factor‐dependent and ‐independent manner. In epithelial–mesenchymal transition‐related molecules, E‐cadherin was upregulated by CRK elimination, whereas N‐cadherin, vimentin, and Zeb1 were downregulated. A similar effect was observed following treatment with c‐Met inhibitor SU11274. Depletion of CRK significantly decreased cell proliferation of 5637 and UM‐UC‐3, consistent with reduced activity of ERK. An orthotopic xenograft model with bioluminescent imaging revealed that CRK knockdown significantly attenuated not only tumor volume but also the number of circulating tumor cells, resulted in a complete abrogation of metastasis. Taken together, this evidence uncovered essential roles of CRK in invasive bladder cancer through the hepatocyte growth factor/c‐Met/CRK feedback loop for epithelial–mesenchymal transition induction. Thus, CRK might be a potent molecular target in bladder cancer, particularly for preventing metastasis, leading to the resolution of clinically longstanding critical issues.
CRK elimination decreases primary tumor growth and completely abolished metastasis. UM‐UC‐3 bladder cancer cells labeled with tdTomato‐luc2 (control; empty, CRK depletion; CRKi‐3) were orthotopically injected under the bladder muscle layer in athymic mice. Tumor growth and metastasis were monitored weekly by bioluminescence imaging system.
Circulation of SARS-CoV-2 Omicron XBB has resulted in the emergence of XBB.1.5, a new Variant of Interest. Our phylogenetic analysis suggests that XBB.1.5 evolved from XBB.1 by acquiring the S486P ...spike (S) mutation, subsequent to the acquisition of a nonsense mutation in ORF8. Neutralization assays showed similar abilities of immune escape between XBB.1.5 and XBB.1. We determine the structural basis for the interaction between human ACE2 and the S protein of XBB.1.5, showing similar overall structures between the S proteins of XBB.1 and XBB.1.5. We provide the intrinsic pathogenicity of XBB.1 and XBB.1.5 in hamsters. Importantly, we find that the ORF8 nonsense mutation of XBB.1.5 resulted in impairment of MHC suppression. In vivo experiments using recombinant viruses reveal that the XBB.1.5 mutations are involved with reduced virulence of XBB.1.5. Together, our study identifies the two viral functions defined the difference between XBB.1 and XBB.1.5.
Cancer recurrence can arise owing to rare circulating cancer stem cells (CSCs) that are resistant to chemotherapies and radiotherapies. Here, we show that a double-network hydrogel can rapidly ...reprogramme differentiated cancer cells into CSCs. Spheroids expressing elevated levels of the stemness genes Sox2, Oct3/4 and Nanog formed within 24 h of seeding the gel with cells from any of six human cancer cell lines or with brain cancer cells resected from patients with glioblastoma. Human brain cancer cells cultured on the double-network hydrogel and intracranially injected in immunodeficient mice led to higher tumorigenicity than brain cancer cells cultured on single-network gels. We also show that the double-network gel induced the phosphorylation of tyrosine kinases, that gel-induced CSCs from primary brain cancer cells were eradicated by an inhibitor of the platelet-derived growth factor receptor, and that calcium channel receptors and the protein osteopontin were essential for the regulation of gel-mediated induction of stemness in brain cancer cells.
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