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1.
J Ethnopharmacol ; 324: 117617, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38142876

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Erzhi pills (EZP), a traditional Chinese medicine formula prescribed for the treatment of vitiligo, has shown promising efficacy. However, the oral bioactive components and mechanisms underlying the promotion of melanogenesis by EZP remain unclear. AIM OF THE STUDY: This study aimed to investigate the pharmacological basis and mechanism of EZP in promoting melanogenesis. MATERIALS AND METHODS: UHPLC-TOF-MS analysis was used to identify absorbed phytochemicals in serum after oral administration of EZP. Network pharmacology methods were used to predict potential targets and pathways involved in the melanogenic activity of EZP, resulting in the construction of a "compound-target-pathway" network. Zebrafish and B16F10 cells were used to evaluate the effects of EZP on tyrosinase activity and melanin content. Western blot and ELISA analyses were used to validate the effects of EZP on melanogenesis-related proteins, including MITF, TYR, CREB, p-CREB, and cAMP. RESULTS: UHPLC-TOF-MS analysis identified 36 compounds derived from EZP in serum samples. Network pharmacology predictions revealed 89 target proteins associated with the identified compounds and closely related to vitiligo. GO and KEGG analyses indicated the involvement of the cAMP/PKA signaling pathway in the promotion of melanogenesis by EZP. Experimental results showed that EZP increased tyrosinase activity and melanin content in zebrafish and B16F10 cells without inducing toxicity. Western blot and ELISA results suggested that the melanogenic effect of EZP may be related to the activation of the cAMP/PKA signaling pathway. These results confirm the feasibility of combining serum pharmacological and network pharmacological approaches. CONCLUSIONS: EZP have the potential to increase tyrosinase activity and melanin content in zebrafish and cells possibly through activation of the cAMP/PKA pathway.


Assuntos
Medicamentos de Ervas Chinesas , Melanoma Experimental , Vitiligo , Animais , Melaninas/metabolismo , Peixe-Zebra , Melanogênese , Monofenol Mono-Oxigenase/metabolismo , Melanoma Experimental/tratamento farmacológico , Melanoma Experimental/metabolismo , Linhagem Celular Tumoral , Fator de Transcrição Associado à Microftalmia/metabolismo
3.
Front Oncol ; 12: 971532, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36203429

RESUMO

Background: Hepatocellular carcinoma (HCC) patients with portal vein tumor thrombus (PVTT) have conventionally been regarded as a contraindication for liver transplantation (LT). However, the outcomes of deceased donor liver transplantation (DDLT) in patients with segmental PVTT remain unknown. The aim of this study is to evaluate the feasibility and effectiveness of DDLT in the treatment of HCC with segmental PVTT. Methods: We retrospectively analyzed 254 patients who underwent DDLT for HCC in our institution from January 2015 to November 2019. To assess the risks of PVTT, various clinicopathological variables were evaluated. Overall (OS) and recurrence-free survival (RFS) analyses based on different PVTT types were performed in HCC patients. Results: Of the 254 patients, a total of 46 patients had PVTT, of whom 35 had lobar PVTT and 11 had segmental PVTT in second-order branches or below. Alpha-fetoprotein (AFP) level, tumor maximal diameter, histological grade, micro-vascular invasion (MVI), RFS, and OS were significantly different between the control and PVTT groups. Lobar PVTT was associated with unfavorable 5-year RFS and OS compared with MVI group (28.6% and 17.1%, respectively). Instead, no significant difference was observed between the segmental PVTT and MVI group in terms of 5-year RFS and OS (RFS: 36.4% vs. 40.4%, p=0.667; OS: 54.5% vs. 45.1%, p=0.395). Further subgroup analysis showed segmental PVTT with AFP levels ≤100 ng/ml presented significantly favorable RFS and OS rates than those with AFP level >100 ng/ml (p=0.050 and 0.035, respectively). Conclusions: In summary, lobar PVTT remains a contraindication to DDLT. HCC patients with segmental PVTT and AFP level ≤100 ng/ml may be acceptable candidates for DDLT.

4.
Immunology ; 164(3): 507-523, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34115389

RESUMO

Loss of the B2M gene is associated with tumour immune escape and resistance to immunotherapy. However, genetic alterations of the B2M gene are rare. We performed an integrative analysis of the mutational and transcriptional profiles of large cohorts of non-small-cell lung cancer (NSCLC) patients and found that epigenetic downregulation of B2M is common. B2M-low tumours exhibit a suppressive immune microenvironment characterized by reduced infiltration of immune cells of various lineages; in B2M-high tumours, more T and natural killer cells are present, but their activities are constrained by immune checkpoint molecules, indicating the diverse mechanisms of immune evasion. High levels of B2M mRNA, but not PD-L1, are correlated with an enhanced response to PD-1-based immunotherapy, suggesting its value for immunotherapy response prediction in solid tumours. Notably, a high tumour mutation burden (TMB) is associated with low B2M expression, which may explain the poor predictive value of the TMB in some situations. In syngeneic mouse models, genetic ablation of B2M in tumour cells causes resistance to PD-1-based immunotherapy, and B2M knockdown also diminishes the therapeutic efficacy. Moreover, forced expression of B2M in tumour models improves the response to immunotherapy, suggesting that B2M levels have significant impacts on treatment outcomes. Finally, we provide insight into the roles of transcription factors and KRAS mutations in B2M expression and the anticancer immune response. In conclusion, genetic and epigenetic regulation of B2M fundamentally shapes the NSCLC immune microenvironment and may determine the response to checkpoint blockade-based immunotherapy.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Pulmonar de Células não Pequenas/imunologia , Neoplasias Pulmonares/imunologia , Microglobulina beta-2/genética , Animais , Antígeno B7-H1/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Conjuntos de Dados como Assunto , Modelos Animais de Doenças , Regulação para Baixo/imunologia , Resistencia a Medicamentos Antineoplásicos/genética , Epigênese Genética/imunologia , Regulação Neoplásica da Expressão Gênica/imunologia , Técnicas de Silenciamento de Genes , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Camundongos , Mutação , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Proteínas Proto-Oncogênicas p21(ras)/genética , Evasão Tumoral/genética , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
5.
Food Microbiol ; 92: 103572, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32950157

RESUMO

Shiga toxigenic Escherichia coli (STEC) can form biofilms and frequently cause serious foodborne illnesses. A strain of STEC O145:H25 (EC19990166) known to be a strong biofilm former was used to evaluate the efficacy of bacteriophage AZO145A against biofilms formed on stainless steel (SS) coupons. Exposure of STEC O145:H25 to phage AZO145A (1010 PFU/mL) for 2 h resulted in a 4.0 log10 reduction (P < 0.01) of planktonic cells grown in M9 broth at 24 °C for 24 h, while reductions were 2.0 log10 CFU/mL if these cells were grown for 48 h or 72 h prior to phage treatment. STEC O145 biofilms formed on SS coupons for 24, 48 and 72 h were reduced (P < 0.01) 2.9, 1.9 and 1.9 log10 CFU/coupon by phages. STEC O145 cells in biofilms were readily transferred from the surface of the SS coupon to beef (3.6 log10 CFU/coupon) even with as little as 10 s of contact with the meat surface. However, transfer of STEC O145 cells from biofilms that formed on SS coupons for 48 h to beef was reduced (P < 0.01) by 3.1 log10 CFU by phage (2 × 1010 PFU/mL) at 24 °C. Scanning electron microscopy revealed that bacterial cells within indentations on the surface of SS coupons were reduced by phage. These results suggest that bacteriophage AZO145A could be effective in reducing the viability of biofilm-adherent STEC O145 on stainless steel in food industry environments.


Assuntos
Bacteriófagos/fisiologia , Contaminação de Equipamentos/prevenção & controle , Carne/microbiologia , Escherichia coli Shiga Toxigênica/virologia , Aço Inoxidável/análise , Animais , Biofilmes , Bovinos , Manipulação de Alimentos/instrumentação , Escherichia coli Shiga Toxigênica/crescimento & desenvolvimento , Escherichia coli Shiga Toxigênica/fisiologia
6.
Exp Cell Res ; 360(2): 81-93, 2017 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-28870599

RESUMO

Immortalized human hepatocytes (IHH) could provide an unlimited supply of hepatocytes, but insufficient differentiation and phenotypic instability restrict their clinical application. This study aimed to determine the role of hepatocyte nuclear factor 4A (HNF4A) in hepatic differentiation of IHH, and whether encapsulation of IHH overexpressing HNF4A could improve liver function and survival in rats with acute liver failure (ALF). Primary human hepatocytes were transduced with lentivirus-mediated catalytic subunit of human telomerase reverse transcriptase (hTERT) to establish IHH. Cells were analyzed for telomerase activity, proliferative capacity, hepatocyte markers, and tumorigenicity (c-myc) expression. Hepatocyte markers, hepatocellular functions, and morphology were studied in the HNF4A-overexpressing IHH. Hepatocyte markers and karyotype analysis were completed in the primary hepatocytes using shRNA knockdown of HNF4A. Nuclear translocation of ß-catenin was assessed. Rat models of ALF were treated with encapsulated IHH or HNF4A-overexpressing IHH. A HNF4A-positive IHH line was established, which was non-tumorigenic and conserved properties of primary hepatocytes. HNF4A overexpression significantly enhanced mRNA levels of genes related to hepatic differentiation in IHH. Urea levels were increased by the overexpression of HNF4A, as measured 24h after ammonium chloride addition, similar to that of primary hepatocytes. Chromosomal abnormalities were observed in primary hepatocytes transfected with HNF4A shRNA. HNF4α overexpression could significantly promote ß-catenin activation. Transplantation of HNF4A overexpressing IHH resulted in better liver function and survival of rats with ALF compared with IHH. HNF4A improved hepatic differentiation of IHH. Transplantation of HNF4A-overexpressing IHH could improve the liver function and survival in a rat model of ALF.


Assuntos
Diferenciação Celular/genética , Fator 4 Nuclear de Hepatócito/fisiologia , Hepatócitos/fisiologia , Hepatócitos/transplante , Falência Hepática Aguda/terapia , Fígado/fisiologia , Adulto , Animais , Linhagem Celular Transformada , Sobrevivência Celular/genética , Células Cultivadas , Hepatócitos/patologia , Humanos , Falência Hepática Aguda/genética , Falência Hepática Aguda/patologia , Transplante de Fígado/métodos , Masculino , Ratos , Ratos Sprague-Dawley
7.
Cancer Biol Ther ; 17(5): 558-65, 2016 05 03.
Artigo em Inglês | MEDLINE | ID: mdl-27124543

RESUMO

Mesenchymal stem cells (MSCs) hold promise as cellular vehicles for the delivery of therapeutic gene products because they can be isolated, expanded, and genetically modified in vitro and possess tumor-oriented homing capacity in vivo. (1) Hepatocyte nuclear factor 4α (HNF4α) is a dominant transcriptional regulator of hepatocyte differentiation and hepatocellular carcinogenesis (HCC). (2,3) We have previously demonstrated that overexpression of HNF4α activates various hepatic-specific genes and enhances MSC differentiation. (4) However, the extent that overexpression of HNF4α in MSCs influences HCC progression has yet to be examined. Here we sought to investigate what effect MSCs overexpressing HNF4α (MSC-HNF4α) have on human hepatoma cells in vitro and in vivo. Conditioned medium collected from in vitro MSC-HNF4α cultures significantly inhibited hepatoma cell growth and metastasis compared with controls. Additionally, nude mice administered MSC-HNF4α exhibited significantly smaller tumors compared with controls in vivo. Immunoblot analysis of HCC cells treated with MSC-HNF4α displayed downregulated ß-catenin, cyclinD1, c-Myc, MMP2 and MMP9. Taken together, our results demonstrate that MSC-HNF4α inhibits HCC progression by reducing hepatoma cell growth and metastasis through downregulation of the Wnt/ß-catenin signaling pathway.


Assuntos
Carcinoma Hepatocelular/genética , Fatores Nucleares de Hepatócito/metabolismo , Neoplasias Hepáticas/genética , Células-Tronco Mesenquimais/metabolismo , Via de Sinalização Wnt/genética , Animais , Carcinoma Hepatocelular/patologia , Proliferação de Células , Regulação para Baixo , Humanos , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Nus , Transfecção
8.
World J Gastroenterol ; 20(1): 126-32, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-24415865

RESUMO

Hepatocellular carcinoma (HCC), which develops from liver cirrhosis, is highly prevalent worldwide and is a malignancy that leads to liver failure and systemic metastasis. While surgery is the preferred treatment for HCC, intervention and liver transplantation are also treatment options for end-stage liver disease. However, the success of partial hepatectomy and intervention is hindered by the decompensation of liver function. Conversely, liver transplantation is difficult to carry out due to its high cost and the lack of donor organs. Fortunately, research into bone-marrow stromal cells (BMSCs) has opened a new door in this field. BMSCs are a type of stem cell with powerful proliferative and differential potential that represent an attractive tool for the establishment of successful stem cell-based therapy for liver diseases. A number of different stromal cells contribute to the therapeutic effects exerted by BMSCs because BMSCs can differentiate into functional hepatic cells and can produce a series of growth factors and cytokines capable of suppressing inflammatory responses, reducing hepatocyte apoptosis, reversing liver fibrosis and enhancing hepatocyte functionality. Additionally, it has been shown that BMSCs can increase the apoptosis rate of cancer cells and inhibit tumor metastasis in some microenvironments. This review focuses on BMSCs and their possible applications in liver regeneration and metastasis after hepatectomy.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia , Neoplasias Hepáticas/cirurgia , Regeneração Hepática , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/fisiologia , Animais , Carcinoma Hepatocelular/fisiopatologia , Carcinoma Hepatocelular/secundário , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/fisiopatologia , Resultado do Tratamento
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