Sarcoma is a rare type of cancer for which new therapeutic agents are required. Ferroptosis is a nonapoptotic cell death triggered by iron-mediated lipid peroxidation. We found that TFRC, an iron ...uptake protein, was expressed at higher levels in sarcoma cell lines than in noncancer and carcinoma cell lines. Glutathione peroxidase 4 (GPX4) protects cells against ferroptosis, and its inhibition using RAS-selective lethal 3 (RSL3) had an antitumor effect that was more pronounced in sarcoma cell lines, particularly synovial sarcoma cells, compared to non-sarcoma cells. Because NF-κB can provoke ferroptosis, we examined the role of SHARPIN, an activator of NF-κB, in sarcoma. We found that SHARPIN expression was significantly associated with reduced survival in cohorts of patients with cancer, including sarcoma. In addition, SHARPIN promoted the sensitivity of sarcoma cells to ferroptosis. Further analyses revealed that the PGC1α/NRF2/SLC7A11 axis and BNIP3L/NIX-mediated mitophagy are regulated through NF-κB and PRMT5 downstream of SHARPIN. Our findings suggest that ferroptosis could have a therapeutic effect in sarcoma, particularly in subpopulations with high TFRC and SHARPIN expression.
Although biological resources are essential for basic and preclinical research in the oncological field, those of sarcoma are not sufficient for rapid development of the treatment. So far, some ...sarcoma cell lines have been established, however, the success rate was low and the established sarcoma types were frequently biased. Therefore, an efficient culture method is needed to determine the various types of sarcomas. Organoid culture is a 3-dimentional culture method that enables the recapitulation of the tumor microenvironment and the success rate reported is higher than the 2-dimentional culture. The purpose of this study was to report our newly established organoids from human epithelioid sarcoma using the air-liquid interface organoid culture method.
We treated 2 patients with epithelioid sarcoma in our institute. The remaining sarcoma specimens after surgical resection were embedded in collagen type 1 gels according to the air-liquid interface organoid culture method. After serial passages, we xenografted the organoids to NOD-scid IL2Rgnull (NSG) mice. Using the developed tumors, we performed histological and genomic analyses to compare the similarities and differences with the original epithelioid sarcoma from the patient.
Organoids from the epithelioid sarcoma could be serially cultured and maintained in collagen type 1 gels for more than 3 passages. Developed orthotopic tumor xenografts were detected in the NSG mice. After the process was repeated severally, the patient derived organoid lines from the epithelioid sarcoma were established. The established organoids showed loss of integrase interactor 1 expression with polymerase chain reaction and immunohistochemical analyses. The xenografted organoids of the epithelioid sarcoma had histologically similar phenotypes with the original tumor and genetically resembled it to some degree.
The present study demonstrated 2 novel established organoid models of epithelioid sarcoma, and our organoid models could be used to investigate the molecular pathogenesis and develop a novel treatment.
Highly diastereoselective intramolecular C–H bond activation at a prochiral sp
3 carbon was achieved with a cationic iridium complex having an optically active heterochelate PN*(R) PN*(R)=
o-Ph
2PC
...6H
4CH
2OCH
2
▪ ligand.
Highly diastereoselective intramolecular C–H bond activation at a prochiral sp
3 carbon was achieved with a cationic iridium complex having an optically active heterochelate PN*(R) PN*(R)=
o-Ph
2PC
6H
4CH
2OCH
2
▪ ligand.
Parkinson disease (PD) is caused by loss of dopamine, which is synthesized from tyrosine by two enzymes, tyrosine hydroxylase (TH) and 4-dihydroxy-l-phenylalanine decarboxylase (DDC). DJ-1 is a ...causative gene for the familial form of PD, but little is known about the roles of DJ-1 in dopamine synthesis. In this study, we found that DJ-1 directly bound to TH and DDC and positively regulated their activities in human dopaminergic cells. Mutants of DJ-1 found in PD patients, including heterozygous mutants, lost their activity and worked as dominant-negative forms toward wild-type DJ-1. When cells were treated with H2O2, 6-hydroxydopamine, or 1-methyl-4-phenylpyridinium, changes in activities of TH and DDC accompanied by oxidation of cysteine 106 of DJ-1 occurred. It was found that DJ-1 possessing Cys-106 with SH and SOH forms was active and that DJ-1 possessing Cys-106 with SO2H and SO3H forms was inactive in terms of stimulation of TH and DDC activities. These findings indicate an essential role of DJ-1 in dopamine synthesis and contribution of DJ-1 to the sporadic form of PD.
► DJ-1 stimulates VMAT2 activity by transactivation of the VMAT 2 gene. ► DJ-1 directly bound to VMAT2 and was co-localized with VMAT2. ► Cysteine 106 of DJ-1 is necessary for the stimulating ...activity of DJ-1 toward VMAT2. ► DJ-1 stimulates re-uptake of excess dopamine into synaptic vesicles.
Loss-of-functional mutation in the DJ-1 gene causes a subset of familial Parkinson’s disease. The mechanism underlying DJ-1-related selective vulnerability in the dopaminergic pathway is, however, not known. Dopamine is synthesized by two enzymes and then packed into synaptic vesicles by vesicular monoamine transporter 2 (VMAT2). In this study, we found that knockdown of DJ-1 expression reduced the levels of mRNA and protein of VMAT2, resulting in reduced VMAT2 activity. Co-immunoprecipitation and pull-down experiments revealed that DJ-1 directly bound to VMAT2, and DJ-1 was co-localized with VMAT2 in cells. Furthermore, ectopic expression of wild-type DJ-1, but not that of L166P, M26I and C106S mutants of DJ-1, increased mRNA and protein levels of VMAT2 and VMAT2 activity. Since VMAT2 and a portion of DJ-1 are localized in the synaptic membrane, these results suggest that DJ-1, but not pathogenically mutated DJ-1, stimulates VMAT2 activity in the synapse by transactivation of the VMAT gene and by direct binding to VMAT2 and that cysteine 106 is necessary for the stimulating activity of DJ-1 toward VMAT2.
Loss-of-function mutation in the DJ-1 gene causes a subset of familial Parkinson disease. The mechanism underlying DJ-1-related selective vulnerability in the dopaminergic pathway is, however, not ...known. DJ-1 has multiple functions, including transcriptional regulation, and one of transcriptional target genes for DJ-1 is the tyrosine hydroxylase (TH) gene, the product of which is a key enzyme for dopamine biosynthesis. It has been reported that DJ-1 is a neuroprotective transcriptional co-activator that sequesters a transcriptional co-repressor polypyrimidine tract-binding protein-associated splicing factor (PSF) from the TH gene promoter. In this study, we found that knockdown of human DJ-1 by small interference RNA in human dopaminergic cell lines attenuated TH gene expression and 4-dihydroxy-l-phenylalanine production but that knockdown or knock-out of mouse DJ-1 in mouse cell lines or in mice did not affect such expression and TH activity. In reporter assays using the human TH gene promoter linked to the luciferase gene, stimulation of TH promoter activity was observed in human cells, but not mouse cells, that had been transfected with DJ-1. Although human DJ-1 and mouse DJ-1 were associated either with human or with mouse PSF, TH promoter activity inhibited by PSF was restored by human DJ-1 but not by mouse DJ-1. Chromatin immunoprecipitation assays revealed that the complex of PSF with DJ-1 bound to the human but not the mouse TH gene promoter. These results suggest a novel species-specific transcriptional regulation of the TH promoter by DJ-1 and one of the mechanisms for no reduction of TH in DJ-1-knock-out mice.
Background
In Japan, ropinirole controlled‐release tabletsrecently became available for Parkinson's disease.
Aim
We compared the efficacy and safety of ropinirole controlled‐release with ropinirole ...immediate‐release.
Methods
We carried out a phase III clinical trial (randomized, double‐blind, double‐dummy), in which controlled‐release (n = 156) or immediate‐release (n = 146) was given to Japanese patients with advanced Parkinson's disease under L‐dopa treatment. First, we assessed the non‐inferiority of ropinirole controlled‐release to immediate‐release at week 24 by measuring change from week 0 in total score of the Unified Parkinson's Disease Rating Scale Part III. Then, during weeks 26–32, we evaluated the safety and efficacy of patients’ switching from ropinirole immediate‐release to controlled‐release, and a subset of patients continued on ropinirole controlled‐release though week 54.
Results
The change in the Unified Parkinson's Disease Rating Scale Part III total score at week 24 was −10.8 for the controlled‐release group and −11.1 for the immediate‐release group (adjusted mean difference: 0.34, two‐sided 95% confidence interval −1.41 to 2.09), and the upper limit of the confidence interval was less than the predefined margin of 2.5, showing the non‐inferiority of ropinirole controlled‐release to immediate‐release. The efficacy did not change after overnight switching from ropinirole immediate‐release to controlled‐release, and lasted until week 54. Adverse events were comparable between the two groups during the whole study period.
Conclusions
As adjunctive therapy to L‐dopa, ropinirole controlled‐release improved motor symptoms in Japanese patients with advanced Parkinson's disease. The overnight switch from immediate‐release to controlled‐release did not result in any unexpected adverse event.
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