111 research outputs found

    Systemically Administered RNAi Molecule Sensitizes Malignant Pleural Mesotheliomal Cells to Pemetrexed Therapy

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    Pemetrexed (PMX) is a key drug for the management of malignant pleural mesothelioma (MPM). However, its therapeutic efficacy is cruelly restricted in many clinical settings by the overexpression of thymidylate synthase (TS) gene. Recently, we emphasized the efficacy of locally administered shRNA designed against TS gene in enhancing the cytotoxic effect of PMX against orthotopically implanted MPM cells in tumor xenograft tumor model. Herein, we explored the efficiency of systemic, rather than local, delivery of TS RNAi molecule in sensitizing MPM cells to the cytotoxic effect of PMX. We here designed a PEG-coated TS shRNA-lipoplex (PEG-coated TS shRNA-lipoplex) for systemic injection. PEG modification efficiently delivered TS shRNA in the lipoplex to tumor tissue following intravenous administration as indicated by a significant suppression of TS expression level in tumor tissue. In addition, the combined treatment of PMX with systemic injection of PEG-coated TS shRNA-lipoplex exerted a potent antitumor activity in a s.c. xenograft tumor model, compared to a single treatment with either PMX or PEG-coated TS shRNA-lipoplex. Metastasis, or the spread, of mesothelioma substantially dedicates the effectiveness of treatment options. The systemic, in addition to local, delivery of tumor targeted anti-TS RNAi system we propose in this study might be an effective option to extend the clinical utility of PMX in treating malignant mesothelioma

    Metronomic S-1 dosing and thymidylate synthase silencing have synergistic antitumor efficacy in a colorectal cancer xenograft model

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    Metronomic chemotherapy is currently considered an emerging therapeutic option in clinical oncology. S-1, an oral formulation of Tegafur (TF), a prodrug of 5-fluorouracil (5-FU), is designed to improve the antitumor activity of 5-FU in tandem with reducing its toxicity. Clinically, metronomic S-1 dosing has been approved for the standard first- and second-line treatment of metastatic or advanced stage of colorectal (CRC). However, expression of intratumor thymidylate synthase (TS), a significant gene in cellular proliferation, is associated with poor outcome to 5-FU-based chemotherapeutic regimens. In this study, therefore, we examined the effect of a combination of TS silencing by an RNA interfering molecule, chemically synthesized short hairpin RNA against TS (shTS), and 5-FU on the growth of human colorectal cancer cell (DLD-1) both in vitro and in vivo. The combined treatment of both shTS with 5-FU substantially inhibited cell proliferation in vitro. For in vivo treatments, the combined treatment of metronomic S-1 dosing with intravenously injected polyethylene glycol (PEG)-coated shTS-lipoplex significantly suppressed tumor growth, compared to a single treatment of either S-1 or PEG-coated shTS-lipoplex. In addition, the combined treatment increased the proportion of apoptotic cells in the DLD-1 tumor tissue. Our results suggest that metronomic S-1 dosing combined with TS silencing might represent an emerging therapeutic strategy for the treatment of patients with advanced CRC

    Biomarkers Predictive of Distant Disease-free Survival Derived from Diffusion-weighted Imaging of Breast Cancer

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    Purpose: To investigate whether intravoxel incoherent motion (IVIM) and/or non-Gaussian diffusion parameters are associated with distant disease-free survival (DDFS) in patients with invasive breast cancer. Methods: From May 2013 to March 2015, 101 patients (mean age 60.0, range 28-88) with invasive breast cancer were evaluated prospectively. IVIM parameters (flowing blood volume fraction [ɪᴠɪᴍ] and pseudodiffusion coefficient [D*]) and non-Gaussian diffusion parameters (theoretical apparent diffusion coefficient [ADC] at a b value of 0 s/mm² [ADC₀] and kurtosis [K]) were estimated using a diffusion-weighted imaging series of 16 b values up to 2500 s/mm². Shifted ADC values (sADC₂₀₀-₁₅₀₀) and standard ADC values (ADC₀-₈₀₀) were also calculated. The Kaplan-Meier method was used to generate survival analyses for DDFS, which were compared using the log-rank test. Univariable Cox proportional hazards models were used to assess any associations between each parameter and distant metastasis-free survival. Results: The median observation period was 80 months (range, 35-92 months). Among the 101 patients, 12 (11.9%) developed distant metastasis, with a median time to metastasis of 79 months (range, 10-92 months). Kaplan-Meier analysis showed that DDFS was significantly shorter in patients with K > 0.98 than in those with K ≤ 0.98 ( = 0.04). Cox regression analysis showed a marginal statistical association between K and distant metastasis-free survival ( = 0.05). Conclusion: Non-Gaussian diffusion may be associated with prognosis in invasive breast cancer. A higher K may be a marker to help identify patients at an elevated risk of distant metastasis, which could guide subsequent treatment

    cis interaction of CD153 with TCR/CD3 is crucial for the pathogenic activation of senescence-associated T cells

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    老化T細胞が自己免疫病や慢性炎症疾患を引き起こすメカニズムを解明 --老化関連疾患克服への新しいアプローチ--. 京都大学プレスリリース. 2022-09-22.With age, senescence-associated (SA) CD4+ T cells that are refractory to T cell receptor (TCR) stimulation are increased along with spontaneous germinal center (Spt-GC) development prone to autoantibody production. We demonstrate that CD153 and its receptor CD30 are expressed in SA-T and Spt-GC B cells, respectively, and deficiency of either CD153 or CD30 results in the compromised increase of both cell types. CD153 engagement on SA-T cells upon TCR stimulation causes association of CD153 with the TCR/CD3 complex and restores TCR signaling, whereas CD30 engagement on GC B cells induces their expansion. Administration of an anti-CD153 antibody blocking the interaction with CD30 suppresses the increase in both SA-T and Spt-GC B cells with age and ameliorates lupus in lupus-prone mice. These results suggest that the molecular interaction of CD153 and CD30 plays a central role in the reciprocal activation of SA-T and Spt-GC B cells, leading to immunosenescent phenotypes and autoimmunity

    A nucleoside anticancer drug, 1-(3-C-ethynyl-β-D-ribo-pentofuranosyl)cytosine (TAS106), sensitizes cells to radiation by suppressing BRCA2 expression

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    <p>Abstract</p> <p>Background</p> <p>A novel anticancer drug 1-(3-C-ethynyl-β-D-ribo-pentofuranosyl)cytosine (ECyd, TAS106) has been shown to radiosensitize tumor cells and to improve the therapeutic efficiency of X-irradiation. However, the effect of TAS106 on cellular DNA repair capacity has not been elucidated. Our aim in this study was to examine whether TAS106 modified the repair capacity of DNA double-strand breaks (DSBs) in tumor cells.</p> <p>Methods</p> <p>Various cultured cell lines treated with TAS106 were irradiated and then survival fraction was examined by the clonogenic survival assays. Repair of sublethal damage (SLD), which indicates DSBs repair capacity, was measured as an increase of surviving cells after split dose irradiation with an interval of incubation. To assess the effect of TAS106 on the DSBs repair activity, the time courses of γ-H2AX and 53BP1 foci formation were examined by using immunocytochemistry. The expression of DNA-repair-related proteins was also examined by Western blot analysis and semi-quantitative RT-PCR analysis.</p> <p>Results</p> <p>In clonogenic survival assays, pretreatment of TAS106 showed radiosensitizing effects in various cell lines. TAS106 inhibited SLD repair and delayed the disappearance of γ-H2AX and 53BP1 foci, suggesting that DSB repair occurred in A549 cells. Western blot analysis demonstrated that TAS106 down-regulated the expression of BRCA2 and Rad51, which are known as keys among DNA repair proteins in the homologous recombination (HR) pathway. Although a significant radiosensitizing effect of TAS106 was observed in the parental V79 cells, pretreatment with TAS106 did not induce any radiosensitizing effects in BRCA2-deficient V-C8 cells.</p> <p>Conclusions</p> <p>Our results indicate that TAS106 induces the down-regulation of BRCA2 and the subsequent abrogation of the HR pathway, leading to a radiosensitizing effect. Therefore, this study suggests that inhibition of the HR pathway may be useful to improve the therapeutic efficiency of radiotherapy for solid tumors.</p

    A novel intraperitoneal therapy for gastric cancer with DFP‐10825, a unique RNAi therapeutic targeting thymidylate synthase, in a peritoneally disseminated xenograft model

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    Purpose: In advanced gastric cancer, peritoneal dissemination is a life‐threatening mode of metastasis. Since the treatment options with conventional chemotherapy remain limited, any novel therapeutic strategy that could control such metastasis would improve the outcome of treatment. We recently developed a unique RNA interference therapeutic regimen (DFP‐10825) consisting of short hairpin RNA against thymidylate synthase (TS shRNA) and cationic liposomes. The treatment with DFP‐10825 has shown remarkable antitumor activity in peritoneally disseminated human ovarian cancer–bearing mice via intraperitoneal administration. In this study, we expanded DFP‐10825 to the treatment of peritoneally disseminated gastric cancer. Methods: DFP‐10825 was administered intraperitoneally into mice with intraperitoneally implanted human gastric cancer cells (MKN45 or NCI‐N87). Antitumor activity and host survival benefits were monitored. Intraperitoneal distribution of fluorescence‐labeled DFP‐10825 was monitored in this MKN45 peritoneally disseminated mouse model. Results: Intraperitoneal injection of DFP‐10825 suppressed tumor growth in two peritoneally disseminated cancer models (MKN45 and NCI‐N87) and increased the survival time of the MKN45 model without severe side effects. Throughout the treatment regimen, no significant body weight loss was associated with the administration of DFP‐10825. Interestingly, after intraperitoneal injection, fluorescence‐labeled DFP‐10825 retained for more than 72 hours in the peritoneal cavity and selectively accumulated in disseminated tumors. Conclusions: Intraperitoneal injection of DFP‐10825 demonstrated effective antitumor activity without systemic severe adverse effects via the selective delivery of RNAi molecules into disseminated tumors in the peritoneal cavity. Our current study indicates that DFP‐10825 could become an alternative option to improve the outcomes of patients with peritoneally disseminated gastric cancer

    Simple and Rapid Enzymatic Method for the Synthesis of Single-Strand Oligonucleotides Containing Trifluorothymidine

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    To investigate the mechanism of trifluorothymidine (TFT)-induced DNA damage, we developed an enzymatic method for the synthesis of single-strand oligonucleotides containing TFT-monophosphate residues. Sixteen-mer oligonucleotides and 14-mer 5′-phosphorylated oligonucleotides were annealed to the template of 25-mer, so as to empty one nucleotide site. TFT-triphosphate was incorporated into the site by DNA polymerase and then ligated to 5′-phosphorylated oligonucleotides by DNA ligase. The synthesized 31-mer oligonucleotides containing TFT residues were isolated from the 25-mer complementary template by denaturing polyacrylamide electrophoresis. Using these single-strand oligonucleotides containing TFT residues, the cleavage of TFT residues from DNA, using mismatch uracil-DNA glycosylase (MUG) of E.coli origin, was compared with that of 5-fluorouracil (5FU) and 5-bromodeoxyuridine (BrdU). The TFT/A pair was not cleaved by MUG, while the other pairs, namely, 5FU/A, 5FU/G, BrdU/A, BrdU/G, and TFT/G, were easily cleaved from each synthesized DNA. Thus, this method is useful for obtaining some site-specifically modified oligonucleotides

    当科で経験した側頭骨線維性骨異形成症の1例

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    線維性骨異形成症は,骨の吸収,未熟な骨梁の新生を主病変とし,骨の形成異常を原因とする非腫瘍性骨疾患であり,四肢の長管骨,肋骨,頭蓋顔面骨に好発し,頭蓋顔面骨では上顎骨,下顎骨の報告はしばしば散見されるが,側頭骨発生の頻度は少ない.今回,我々は側頭骨に生じた線維性骨異形成症の1例を経験したので文献的考察を加え報告する.症例は53歳男性.20XX年4月初旬,左耳痛・耳漏を主訴に近医を受診し,急性中耳炎と診断され治療を行われるも改善乏しく,5月中旬紹介となった.初診時,外耳道,鼓膜所見に異常は認めず,純音聴力検査では軽度の気導-骨導差を認め左混合難聴であった.CT所見で左外耳道,鼓室内には軟部陰影は認めなかったが,左乳突蜂巣内に側頭骨の菲薄化,破壊像を認め,周囲にスリガラス陰影を呈する比較的低吸収域の軟部陰影を認めた,またMRI所見では,左乳突蜂巣内に,T1強調像で小脳実質と等信号であり,周囲に造影効果を認め,T2強調像で周囲が高信号な辺縁整で境界明瞭な腫瘤性病変を認めた.これらから,組織学的検査目的で手術を行った.左耳後切開し,外耳道を剥離し,鼓室・上鼓室を明視下に置き,中耳腔全体を観察した.鼓膜は正常であったが,ツチ-キヌタ骨関節に軽度な肉芽組織を認めたが,アブミ骨の可動性は良好であった.乳突洞削開術を行うと,骨は脆弱でもろく,乳突蜂巣に肉芽病変が充満し,乳様突起先端部に直径1cm以下の嚢胞病変を認めた.術中側頭骨及び,嚢胞を病理検査に提出した.中頭蓋底およびS状静脈洞の骨膜が広範囲に破壊されており,この部位に,筋膜および骨を置き,手術終了した.病理組織検査では,形状が不整で骨芽細胞や破骨細胞をほとんど認めない未熟な骨を認め,周囲に間質の疎な線維性結合組織の増殖があった事から線維性骨異形成症と診断した.現在術後12か月になるが,再発なく経過良好である.Fibrous dysplasia(FD) is a benign disease characterized by the progressive replacement of the normal bone element with fibrous tissue. FD is usually found in the long bones, and is rare in the temporal bone. Surgery may be necessary for restoration of conductive hearing loss and prevention of complications. Meatoplasty has often been selected as surgical treatment, and the postoperative restenosis of external auditory canal(EAC) was found in most cases requiring management to prevent restenosis of EAC. Although FD is a benign disease, often to come back or to return, it is nessesary for careful follow up. We report a case of monostotic FD of the temporal bone. The patient was a 53 years old man, who complained of repeatedly ear discharge in the left ear. He have diabetes and hypertension. When a patient is first seen, ear discharge and eardrum perforation is nothing, and otitis media cholesteatoma is not own. The hearing test is left sensorineural hearing impairment. Computed tomography revealed pagetoid and sclerotic changes of the temporal bone. Biopsy was performed and the histological examination diagnosed FD

    CD153/CD30 signaling promotes age-dependent tertiary lymphoid tissue expansion and kidney injury

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    高齢者腎臓病を悪化させる原因細胞・分子の同定に成功. 京都大学プレスリリース. 2021-11-30.A new drug target for kidney disease. 京都大学プレスリリース. 2021-11-30.Tertiary lymphoid tissues (TLTs) facilitate local T- and B-cell interactions in chronically inflamed organs. However, the cells and molecular pathways that govern TLT formation are poorly defined. Here we identify TNF superfamily CD153-CD30 signaling between two unique age-dependent lymphocyte subpopulations, CD153⁺PD-1⁺CD4⁺ senescence-associated T (SAT) cells and CD30+T-bet+ age-associated B cells (ABCs), as a driver for TLT expansion. SAT cells, which produced ABC-inducing factors IL21 and IFNγ, and ABCs progressively accumulated within TLTs in aged kidneys after injury. Notably, in kidney injury models, CD153 or CD30 deficiency impaired functional SAT cell induction, which resulted in reduced ABC numbers and attenuated TLT formation with improved inflammation, fibrosis and renal function. Attenuated TLT formation after transplantation of CD153-deficient bone marrow further supported the importance of CD153 in immune cells. Clonal analysis revealed that SAT cells and ABCs in the kidneys arose from both local differentiation and recruitment from the spleen. In the synovium of aged rheumatoid arthritis patients, T peripheral helper/T follicular helper cells and ABCs also expressed CD153 and CD30, respectively. Together, our data reveal a previously unappreciated function of CD153-CD30 signaling in TLT formation and propose targeting CD153-CD30 signaling pathway as a therapeutic target for slowing kidney disease progression

    Relationship between advanced glycation end products and plaque progression in patients with acute coronary syndrome: the JAPAN-ACS Sub-study.

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    Background: The Japan Assessment of Pitavastatin and Atorvastatin in Acute Coronary Syndrome (JAPAN-ACS) trial demonstrated that early aggressive statin therapy in patients with ACS significantly reduces plaque volume (PV). Advanced glycation end products (AGEs) and the receptors of AGEs (RAGE) may lead to angiopathy in diabetes mellitus (DM) and may affect on the development of coronary PV. The present sub-study of JAPAN-ACS investigates the association between AGEs and RAGE, and PV.Methods: Intravascular ultrasound (IVUS)-guided percutaneous coronary intervention (PCI) was undertaken, followed by the initiation of statin treatment (either 4 mg/day of pitavastatin or 20 mg/day of atorvastatin), in patients with ACS. In the 208 JAPAN-ACS subjects, PV using IVUS in non-culprit segment > 5 mm proximal or distal to the culprit lesion and, serum levels of AGEs and soluble RAGE (sRAGE) were measured at baseline and 8-12 months after PCI.Results: At baseline, no differences in the levels of either AGEs or sRAGE were found between patients with DM and those without DM. The levels of AGEs decreased significantly with statin therapy from 8.6 ± 2.2 to 8.0 ± 2.1 U/ml (p < 0.001), whereas the levels of sRAGE did not change. There were no significant correlations between changes in PV and the changes in levels of AGEs as well as sRAGE. However, high baseline AGEs levels were significantly associated with plaque progression (odds ratio, 1.21; 95% confidence interval, 1.01 - 1.48; p = 0.044) even after adjusting for DM in multivariate logistic regression models.Conclusions: High baseline AGEs levels were associated with plaque progression in the JAPAN-ACS trial. This relationship was independent of DM. These findings suggest AGEs may be related to long-term glucose control and other oxidative stresses in ACS.Trial registration: NCT00242944. © 2013 Fukushima et al.; licensee BioMed Central Ltd
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