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1.
Mol Pharm ; 15(4): 1505-1514, 2018 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-29502410

RESUMO

Pyropheophorbide-a (Pyro) is a highly promising photosensitizer for tumor photodynamic therapy (PDT), although its very limited tumor-accumulation ability seriously restricts its clinical applications. A higher accumulation of photosensitizers is very important for the treatment of deeply seated and larger tumors. The conjugation of Pyro with tumor-homing peptide ligands could be a very useful strategy to optimize the physical properties of Pyro. Herein, we reported our studies on the conjugation of Pyro with a cyclic cRGDfK (cRGD) peptide, an integrin binding sequence, to develop highly tumor-specific photosensitizers for PDT application. To further reduce the nonspecific uptake and, thus, reduce the background distribution of the conjugates in normal tissues, we opted to add a highly hydrophilic polyethylene glycol (PEG) chain and an extra strongly hydrophilic carboxylic acid group as the linker to avoid the direct connection of the strongly hydrophobic Pyro macrocycle and cRGD ligand. We reported here the synthesis and characterization of these conjugates, and the influence of the hydrophilic modification on the biological function of the conjugates was carefully studied. The tumor-accumulation ability and photodynamic-induced cell-killing ability of these conjugates were evaluated through both in vitro cell-based experiment and in vivo distribution and tumor therapy experiments with tumor-bearing mice. Thus, the synthesized conjugate significantly improved the tumor enrichment and tumor selectivity of Pyro, as well as abolished the xenograft tumors in the murine model through a one-time PDT treatment.


Assuntos
Clorofila/análogos & derivados , Peptídeos Cíclicos/química , Fármacos Fotossensibilizantes/química , Animais , Linhagem Celular Tumoral , Clorofila/química , Feminino , Humanos , Interações Hidrofóbicas e Hidrofílicas , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fotoquimioterapia/métodos , Polietilenoglicóis/química , Distribuição Tecidual
2.
Open Med (Wars) ; 19(1): 20230810, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38947217

RESUMO

Leukemia, the most common malignant tumor in childhood, can be categorized into acute leukemia and chronic leukemia. However, the role of FUNDC1 in childhood leukemia (CL) remains unknown. This study aims to investigate the effects of FUNDC1 on patients with CL and its underlying mechanism both in vivo and in vitro. The mRNA expression levels of FUNDC1 were found to be up-regulated in serum samples from CL patients as well as in leukemia cell lines. Furthermore, it was observed that the mRNA expression of FUNDC1 was lower in stage I-II CL patients compared to stage III-IV patients. The up-regulation of FUNDC1 was found to promote leukemia metastasis. Additionally, it was discovered that FUNDC1 up-regulation reduces ferroptosis by inhibiting mitochondrial damage. In a leukemia model, FUNDC1 up-regulation induces the expression of FBXL2. Moreover, FUNDC1 up-regulation reduces FBXL2 ubiquitination, thus maintaining FBXL2 protein expression in leukemia. By inducing FBXL2, FUNDC1 reduces ferroptosis in leukemia through the inhibition of mitochondrial damage. The stability of FUNDC1 is controlled by METTL3 methylation. Overall, this study sheds light on the role of FUNDC1 in CL and provides insights into its underlying mechanisms.

3.
Neuroreport ; 31(17): 1225-1235, 2020 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-33105440

RESUMO

Neuroblastoma is an important problem in children. Long noncoding RNAs (lncRNAs) exhibit important roles in tumorigenicity of neuroblastoma. However, the role and mechanism of lncRNA small nucleolar RNA host gene 16 (SNHG16) in neuroblastoma tumorigenicity remain poorly understood. Forty-six neuroblastoma samples and 28 normal tissues were harvested. The levels of SNHG16, microRNA-15b-5p (miR-15b-5p), and phosphoribosyl pyrophosphate synthetase 1 (PRPS1) were detected via quantitative reverse transcription PCR or western blot. Cell proliferation as well as cycle distribution were measured via 3-(4, 5-Dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide or flow cytometry. Cell metastasis was investigated via epithelial-mesenchymal transition or transwell assay. The target relationship of miR-15b-5p and SNHG16 or PRPS1 was explored via starBase and dual-luciferase reporter assay. The role of SNHG16 in neuroblastoma in vivo was analyzed using a xenograft model. We found SNHG16 and PRPS1 levels were increased in neuroblastoma tissues and cells. SNHG16 knockdown inhibited cell proliferation, increased the cell cycle distribution at G0/G1 phase, and decreased the cells at S phase. SNHG16 overexpression caused an opposite effect. SNHG16 silence suppressed neuroblastoma cell metastasis. PRPS1 knockdown constrained cell proliferation and metastasis and regulated cell cycle distribution. miR-15b-5p was sponged by SNHG16 and directly targeted PRPS1. miR-15b-5p knockdown or PRPS1 overexpression mitigated the influence of SNHG16 silence on cell cycle, proliferation, and metastasis. SNHG16 knockdown reduced xenograft tumor growth. In conclusion, SNHG16 downregulation suppressed neuroblastoma tumorigenicity by regulating cell cycle, proliferation, and metastasis via miR-15b-5p/PRPS1 axis.


Assuntos
Neoplasias Encefálicas/metabolismo , Carcinogênese/metabolismo , MicroRNAs/metabolismo , Neuroblastoma/metabolismo , RNA Longo não Codificante/metabolismo , Ribose-Fosfato Pirofosfoquinase/metabolismo , Animais , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Carcinogênese/genética , Carcinogênese/patologia , Linhagem Celular Tumoral , Criança , Técnicas de Silenciamento de Genes/métodos , Células Endoteliais da Veia Umbilical Humana , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/genética , Neuroblastoma/genética , Neuroblastoma/patologia , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , Ribose-Fosfato Pirofosfoquinase/genética , Ensaios Antitumorais Modelo de Xenoenxerto/métodos
4.
Saudi J Biol Sci ; 26(8): 2108-2112, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31889803

RESUMO

OBJECTIVE: To explore he curative effect and safety of Prednisone in combination with Mycophenolate in treating ITP and its influence on the level of peripheral blood T lymphocytes and NK lymphocytes. METHOD: 93 cases of ITP patients were divided into the observation group and the control group by the Random Number Table method, 48 cases for the observation group, 45 for another. Patients in the control group orally took 0.5 mg/kg Prednisone Acetate tablets daily, two times each in the morning and evening. And the observation group, based on the treatment of the control group, orally took Mycophenolate Mofetil Dispersible tablets twice a day, 1 g each time. According to patients' conditions, 3 to 5 courses were set for treatment with 3 weeks a course. Compared PLT amount and the changing situation of inflammatory factors, CD3+ and CD3+CD95L+ before and after the treatment, the level of CD3+Caspase-3+ and CD3+Caspase-8+, NK+, NK+ CD95L+, NK+Caspase-3+, NK+Caspase-8, the curative effect and adverse events. RESULT: After treatment, PLT amount in both groups increased, and the increase in the observation group was much higher than that of the control group, the difference had statistical significance (P < 0.05). The time needed for PLT amount in the control group to reach the normal and peak values was longer than that of the observation group, whose PLT peak value was higher than another group. The difference had statistical significance (P < 0.05). After the treatment, the levels of TNF-α and IL-6 were lowered, and the value of the observation group was lower than that of another. The difference between and within the group has statistical significance. After the treatment, the level of CD3+, CD3+CD95L+ and CD3+Caspase-8+ is much higher and CD3+Caspase-3+ level lower than that before the treatment. The difference has statistical significance (P < 0.05). After the treatment, the level of NK+ and NK+ CD95L+ is higher and the level of NK+Caspase-8+ lower than that before the treatment. The difference has statistical significance (P < 0.05). After the treatment, the total effective rate 91.67% of the observation group is much higher than that 75.56% of another. The difference has statistical significance (P < 0.05). After the treatment, the incidence rate of adverse events in the control group is 11.11% (5/45), while 4.17% (2/48) in the observation group. The difference between groups has statistical significance (χ2 = 3.890, P < 0.05). CONCLUSION: The curative effect of Prednisone in combination with Mycophenolate on ITP patients is better than orally taking Prednisone tablets. Moreover, when it comes to Prednisone in combination with Mycophenolate, both the PLT amount and immunocompetence are improved without much adverse reaction, and the molecules of peripheral blood T lymphocytes and NK lymphocytes can be effectively adjusted to relieve the symptoms. So the method is trustworthy to be popularized for clinical practices.

5.
J Cancer ; 9(2): 310-320, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29344278

RESUMO

Phthalocyanines (Pcs) are a group of promising photosensitizers for use in photodynamic therapy (PDT). However, their extremely low solubility and their strong tendency to aggregate in aqueous solution greatly restrict their application. Conjugation of Pc macrocycles with peptide ligands could be a very useful strategy to optimize the physical properties of Pcs not only by increasing their water solubility and reducing their aggregation but also by endowing the conjugates with a tumor-targeting capability. To develop highly potent photosensitizers for tumor PDT, we prepared new peptide-conjugated photosensitizers using silicon Pc (SiPc), which has much higher photodynamic activity than zinc Pcs, as the light activation moiety and the cRGDfK peptide (or simply cRGD) as the peptide moiety. A polyethylene glycol linker and an extra carboxylic acid group were also tested for introduction into the conjugates to optimize the conjugate structure. The conjugates' photophysical and photodynamic behaviors were then carefully evaluated and compared using in vitro and in vivo experiments. One of the prepared conjugates, RGD-(Linker)2-Glu-SiPc, showed excellent physical properties and photodynamic activity, with an EC50 (half maximal effective concentration) of 10-20 nM toward various cancer cells. This conjugate eradicated human glioblastoma U87-MG tumors in a xenograft murine tumor model after only one dose of photodynamic treatment, with no tumor regrowth during observation for up to 35 days. The conjugate RGD-(Linker)2-Glu-SiPc thus showed highly promising potential for use in tumor treatment.

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