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1.
Cancer Discov ; 14(2): 326-347, 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-37824278

RESUMO

Pancreatic ductal adenocarcinoma (PDAC) remains a highly lethal malignancy because of its aggressive nature and the paucity of effective treatment options. Almost all registered drugs have proven ineffective in addressing the needs of patients with PDAC. This is the result of a poor understanding of the unique tumor-immune microenvironment (TME) in PDAC. To identify druggable regulators of immunosuppressive TME, we performed a kinome- and membranome-focused CRISPR screening using orthotopic PDAC models. Our data showed that receptor-interacting protein kinase 2 (RIPK2) is a crucial driver of immune evasion of cytotoxic T-cell killing and that genetic or pharmacologic targeting of RIPK2 sensitizes PDAC to anti-programmed cell death protein 1 (anti-PD-1) immunotherapy, leading to prolonged survival or complete regression. Mechanistic studies revealed that tumor-intrinsic RIPK2 ablation disrupts desmoplastic TME and restores MHC class I (MHC-I) surface levels through eliminating NBR1-mediated autophagy-lysosomal degradation. Our results provide a rationale for a novel combination therapy consisting of RIPK2 inhibition and anti-PD-1 immunotherapy for PDAC. SIGNIFICANCE: PDAC is resistant to almost all available therapies, including immune checkpoint blockade. Through in vivo CRISPR screen, we identified that RIPK2 plays a crucial role in facilitating immune evasion by impeding antigen presentation and cytotoxic T-cell killing. Targeting tumor-intrinsic RIPK2 either genetically or pharmacologically improves PDAC to anti-PD-1 immunotherapy. See related commentary by Liu et al., p. 208 . This article is featured in Selected Articles from This Issue, p. 201.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Imunoterapia , Linfócitos T Citotóxicos/metabolismo , Proteínas Quinases , Microambiente Tumoral
2.
Transl Cancer Res ; 11(6): 1770-1780, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35836539

RESUMO

Background: Apatinib is a small-molecule tyrosine kinase inhibitor targeting VEGFR-2, which was recently used in a phase II clinical trial for the treatment of recurrent or metastatic nasopharyngeal carcinoma (rmNPC). However, there is no consistent conclusion on its efficacy and safety on rmNPC. This study conducted a meta-analysis of clinical research on the efficacy and safety of apatinib in the treatment of rmNPC. Methods: In April 2022, the PubMed, Web of Science, Scopus, Chinese National Knowledge Infrastructure (CNKI), CMB, and Wanfang databases were systematically searched, and relevant research literature were screened and analyzed. The clinical trial literatures using apatinib as the main single or combined treatment for rmNPC patients were selected and combined with objective response rate (ORR), disease control rate (DCR), progression-free survival (PFS), overall survival (OS) and other efficacy and safety indicators. Results: The meta-analysis included 12 studies, including 408 patients with rmNPC. The methodological index for nonrandomized studies scale was used to evaluate the bias of the included literatures and found that the bias was low. A total of 408 rmNPC patients were included in the included literature, with 11 studies being a phase II single-arm trial and one being a phase II non-randomized controlled trial. The ORR of patients with rmNPC treated with apatinib was 41.5% (95% CI: 34.8%, 48.2%), and the DCR was 80.2% (95% CI: 70.9%, 89.6%). The median PFS was 6.4 months (95% CI: 5.3, 7.4), and the median OS was 14.8 months (95% CI: 10.7, 18.9). The incidence of hypertension, hand-foot skin reaction, and proteinuria was 31% (95% CI: 19-43%), 29% (95% CI: 20-39%), and 13% (95% CI: 6-20%), respectively. Discussion: The efficacy of apatinib in the treatment of rmNPC patients is similar to that of the previous second-line chemotherapy drugs, but since most studies are phase II single-arm studies, the advantages and disadvantages of the existing second-line chemotherapy regimens cannot be determined.

3.
Front Cell Infect Microbiol ; 11: 790036, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34869083

RESUMO

Interferon gamma-inducible protein 16 (IFI16) is a DNA sensor protein, which triggers interferon-beta (IFN-ß) production. However, the role of IFI16 in the innate immunity against hepatitis B virus (HBV) remains controversial. Peripheral blood mononuclear cells (PBMCs) and serum specimens were collected from 20 patients with chronic hepatitis B (CHB) receiving Peg-IFN-α2b therapy. IFI16 mRNA/protein of PBMCs and serum IFI16 at baseline and changes during Peg-IFN-α2b treatment were detected. The interaction between IFI16 and HBV DNA in the PBMCs was analyzed using chromatin immunoprecipitation assay. Leukemic T cell line CEM-C7 and HBV-replicating HepG2.2.15 cells were used to test the effects of interferon treatment and HBV replication on IFI16 expression. Compared with healthy controls, lower levels of IFI16 mRNA but more significant expression of IFI16 protein with heterogeneous degradation were detected in PBMCs of CHB patients. Early changes in IFI16 mRNA, but not IFNB mRNA of PBMCs or serum IFI16, were correlated to HBeAg seroconversion of Peg-IFN-α2b therapy. An interaction between IFI16 and HBV DNA was detected in the PBMCs. In the cultured HepG2.2.15 and CEM-C7 cells, interferons resulted in the translocalization of IFI16 from the cytoplasm to the nucleus and inhibited IFI16 degradation. IFI16 of PBMCs may play a role in sensing HBV infection, and early change in IFI16 mRNA of PBMCs is valuable to predict HBeAg seroconversion in Peg-IFN-α2b treatment. The influences on IFI16 degradation and subcellular location may present a molecular mechanism of antiviral activity of interferon.


Assuntos
Antivirais , Hepatite B , Proteínas Nucleares/imunologia , Fosfoproteínas/imunologia , Antivirais/uso terapêutico , Células Cultivadas , Hepatite B/tratamento farmacológico , Hepatite B/imunologia , Humanos , Interferon alfa-2/uso terapêutico , Interferon-alfa/uso terapêutico , Leucócitos Mononucleares , Polietilenoglicóis/uso terapêutico , Proteínas Recombinantes/uso terapêutico
4.
Infect Dis Immun ; 1(1): 36-42, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38630102

RESUMO

Background: Pre-existing liver disease is a risk factor for the worse prognosis of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We aimed to evaluate whether chronic hepatitis B (CHB) and hepatocellular carcinoma (HCC) affect the expression of viral receptor angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TMPRSS2) in the liver. Methods: Twelve pairs of matched liver tissues of HCC and para-carcinoma were collected from the First Affiliated Hospital of Zhejiang University School of Medicine. And 20 liver biopsies from CHB patients were collected from Peking University People's Hospital. The expression of ACE2 and TMRPSS2 were detected using immunofluorescence staining, western blot, and RT-qPCR. The effects of hepatitis B virus (HBV) replication or interferon on ACE2 and TMPRSS2 expression were tested in hepatic cell lines. Results: The mRNA expression of TMPRSS2 in HCC tissues was six-fold higher than that of para-carcinoma tissues (P = 0.002), whereas that of ACE2 was not statistically different between HCC and para-carcinoma tissues. Hepatocellular ACE2 expression was detected in 35% (7/20) of CHB patients and mostly distributed in the inflammatory areas. However, there was no difference in TMPRSS2 expression between areas with or without inflammation. IFN-α2b slightly induced ACE2 expression (2.4-fold, P = 0.033) in HepG2 cells but not in Huh-7, QSG-7701, and L-02 cells. IFN-α2b did not affect TMPRSS2 expression in these cell lines. In addition, HBV replication did not alter ACE2 expression in HepAD38 cells. Conclusions: Although HBV replication does not directly affect the expression of ACE2 and TMPRSS2, intrahepatic inflammation and carcinogenesis may increase their expression in some patients, which, in turn, may facilitate SARS-CoV-2 infection in hepatocytes.

5.
Cell Death Dis ; 11(7): 552, 2020 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-32690860

RESUMO

Acute promyelocytic leukemia (APL) therapy involves the compounds cytotoxic to both malignant tumor and normal cells. Relapsed APL is resistant to subsequent chemotherapy. Novel agents are in need to kill APL cells selectively with minimal toxicity. DDX5 has been recognized to be a novel target to suppress acute myeloid leukemia (AML). However, the role of DDX5 remains elusive in APL. Here a DDX5-targeting fully human monoclonal autoantibody named after 2F5 was prepared. It is demonstrated that 2F5 selectively inhibited APL cell proliferation without toxicity to normal neutrophil and tissues. Moreover, 2F5 was confirmed to induce G0/G1 phase arrest in APL cells, and promote APL cell differentiation combined with decreased DDX5 expression and increased reactive oxygen species (ROS) production. Knockdown of DDX5 by siRNA also inhibited proliferation, promoted cell differentiation and enhanced ROS production in APL cells. However, the ROS inhibitor reversed the effects of 2F5 on DDX5 and ROS in APL cells. Thus, we conclude that DDX5-targeting 2F5 inhibits APL cell proliferation, and promotes cell differentiation via induction of ROS. 2F5 showed the therapeutic value of fully human monoclonal autoantibody in APL, which provides a novel and valid approach for treatment of relapse/refractory APL.


Assuntos
Anticorpos Monoclonais/farmacologia , Diferenciação Celular/efeitos dos fármacos , RNA Helicases DEAD-box/antagonistas & inibidores , Leucemia Promielocítica Aguda/metabolismo , Leucemia Promielocítica Aguda/patologia , Espécies Reativas de Oxigênio/metabolismo , Acetilcisteína/farmacologia , Animais , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , RNA Helicases DEAD-box/genética , RNA Helicases DEAD-box/metabolismo , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Inativação Gênica/efeitos dos fármacos , Humanos , Leucemia Promielocítica Aguda/genética , Masculino , Camundongos Endogâmicos BALB C , Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo
6.
Environ Entomol ; 49(3): 667-672, 2020 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-32333018

RESUMO

Polycyclic aromatic hydrocarbons (PAHs), as well-recognized toxic chemical, cause the public hazard in environments. Here, we demonstrated the black soldier fly larvae (BSFL) could tolerate the PAHs and reduce their content. Four typical PAHs (1.0, 10.0, and 100.0 mg/kg), naphthalene, fluorene, phenanthrene, and pyrene, were individually spiked into BSFL conversion systems. The parameters for larval growth, conversion process, and PAHs removal were determined in spiked group and no-spiked control. The results show that the larval development time (19.7-21.0 d) in the half of PAH groups was significantly longer by 2-4 d than those in the control, while the relative growth rates (1.88-1.99% per day) in the majority PAH groups were lower. The larval mortalities (0-2.83%), harvest yields (80.20-85.91 g), conversion rates (14.71-15.83%), and eclosion rates (60.27-82.67%) in almost all of PAH groups did not significantly different from those in the control. The four PAHs potentially delayed the development time of BSFL, slowed the larval growth, and lower waste reduction rates, but these influences were slight and might be caused by the inhibition of PAHs to microbial activity. The BSFL-mortalities, conversion rates, yields, and eclosion rates were not significantly affected by the PAHs. Furthermore, BSFL effectively removed 34.1-84.2% of PAHs from subtracts in 18-21 d. The removal of PAHs with low concentration could be easier than those with high concentration by BSFL. The present results provide an alternative strategy to treat the waste contaminated by PAHs and elucidate the effect of PAHs on insects in the environment.


Assuntos
Dípteros , Hidrocarbonetos Policíclicos Aromáticos , Simuliidae , Animais , Larva , Hidrocarbonetos Policíclicos Aromáticos/toxicidade
7.
RSC Adv ; 8(40): 22583-22591, 2018 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-35539702

RESUMO

The effect of high strain rate and large shear deformation on the orientation of crystallites in high density polyethylene (HDPE) was investigated with dynamic equal-channel-angular pressing (D-ECAP). The HDPE samples were processed by two loading routes, route A and route C. Grid lines were used to obtain macroscopic strain distributions, which were substantiated by finite element modeling. Owing to the strain rate effect, the number of D-ECAP processing passes has a minor effect on the shear strain accumulations compared to ECAP. D-ECAP leads to a decrease in the thickness of the crystalline stem, and the crystallinity. After route-A or route-C D-ECAP processing, a new monoclinic phase emerges, and two types of crystallographic c-axis orientations appear: the crystallographic c-axis is approximately parallel to the flow direction (FD), or is tilted at approximately 55° clockwise away from FD. However, only one type of crystallographic c-axis orientation is detected after 2 passes of route-C D-ECAP. It is viable to utilize D-ECAP to control the structure and orientation of crystalline polymers, as a complement to ECAP and other processing techniques.

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