A Multifunctional Non-viral Vector for the Delivery of MTH1-targeted CRISPR/Cas9 System for Non-Small Cell Lung Cancer Therapy

Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) system adapted from bacteria is a programmable nuclease-based genome editing tool. The long-lasting effect of gene silencing or correction is beneficial in cancer treatment. Considering the need to broaden the practical application of this technology, highly efficient non-viral vectors are urgently required. We prepared a multifunctional non-viral vector that could actively target tumor cells and deliver CRISPR/Cas9 plasmids into nuclei of cancer cells. Protamine sulfate (PS) which contains nuclear localization sequence was utilized to condense plasmid DNA and facilitate nuclei-targeted delivery. Liposome-coated protein/DNA complex avoided the degradation of nuclease in blood circulation. The obtained PS@Lip/pCas9 was further modified with distearoyl phosphoethanolamine-polyethylene glycol-hyaluronic acid (HA) to endow the vector ability to actively target tumor cell. Results suggested that PS@HA-Lip could deliver CRISPR/Cas9 plasmids into nuclei of tumor cells and induce genome editing effect. With the disruption of MTH1 (mutT homolog1) gene, the growth of non-small cell lung cancer was inhibited. Moreover, cell apoptosis in tumor tissue was promoted, and liver metastasis of non-small cell lung cancer (NSCLC) was reduced. Our study has provided a therapeutic strategy targeting MTH1 gene for NSCLC therapy. STATEMENT OF SIGNIFICANCE: CRISPR/Cas9 as a powerful tool for genome editing has drawn much attention. The long-lasting effect possesses unique advantage in cancer treatment. Non-viral vectors have high loading capacity, high safety and low immunogenicity, playing an important role in CRISPR/Cas9 delivery. In our study, a multifunctional non-viral vector for the efficient delivery of CRISPR/Cas9 plasmid was constructed. With the active targeting ligand and nuclei-targeting component, the cargo was efficiently delivered into cell nuclei and exerted genome editing effect. By using this vector, we successfully inhibited the growth and induced the apoptosis of non-small cell lung cancer by disrupting MTH1 expression with good safety. Our work provided an efficient non-vial vector for CRISPR/Cas9 delivery and explored the possibility for cancer treatment.

Coadministration of iRGD peptide with ROS-sensitive nanoparticles co-delivering siFGL1 and siPD-L1 enhanced tumor immunotherapy

The continuous activation and expansion of tumor-specific T cells by various means are the main goal of cancer immunotherapy. Tumor cells overexpress fibrinogen-like protein 1 (FGL1) and programmmed death-ligand 1 (PD-L1), which respectively bind to lymphocyte-activation gene 3 (LAG-3) and programmmed death-1(PD-1) on T cells, forming important signaling pathways (FGL1/LAG-3 and PD-1/PD-L1) that negatively regulate immune responses. In order to interfere with the inhibitory function of FGL1 and PD-L1 proteins, we designed a new type of reactive oxygen species (ROS)-sensitive nanoparticles to load FGL1 siRNA (siFGL1) and PD-L1 siRNA (siPD-L1), which was formed from a stimuli-responsive polymer with a poly-l-lysine-thioketal and modified cis-aconitate to facilitate endosomal escape. Moreover, tumor-penetrating peptide iRGD and ROS-responsive nanoparticles were co-administered to further enhance the delivery efficiency of siFGL1 and siPD-L1, thereby significantly reducing the protein levels of FGL1 and PD-L1 in tumor cells. Our findings indicated that the dual delivery of FGL1/PD-L1 siRNA was a new and powerful treatment method, which was characterized by increasing the infiltration of effector CD4+ and CD8+ T cells, effectively alleviating the tumor immunosuppressive microenvironment. These findings also supported the superiority and feasibility of nanoparticle-mediated tumor immunotherapy, and may provide a different perspective for cancer treatment. STATEMENT OF SIGNIFICANCE: In addition to the idea that cancer vaccines can promote T cell immune responses, nanoparticle delivery modulators (such as small interfering RNA (siRNA) targeting immunosuppressive pathways) may provide more information for the research of nanoparticle-mediated cancer immunotherapy. In this study, we designed a new intelligent nano-delivery system for co-delivery of siFGL1 and siPD-L1, and demonstrated the ability to down-regulate the expression levels of FGL1 and PD-L1 proteins in tumor cells in vitro and in vivo. The constructed nanoparticle had a good tumor microenvironment responsiveness, and the delivery efficiency was enhanced by co-injection with tumor penetrating peptide iRGD. This project proposed a new strategy for tumor immunotherapy based on smart nano-delivery systems, and explored more possibilities for tumor therapy.

Apigenin increases radiosensitivity of glioma stem cells by attenuating HIF-1α-mediated glycolysis

Apigenin, a natural flavonoid compound present in a variety of edible plants and health foods, has an anti-tumor effect and inhibits hypoxia inducible factor-lα (HIF-1α) expression in hypertrophic cardiac tissues. However, whether or not apigenin has a radiosensitization effect on glioma stem cells (GSCs) is unknown. Our present study aimed to investigate the effect of apigenin and its possible mechanisms. The human GSCs SU3 and its radioresistance line SU3-5R were treated with apigenin, radiation, or their combination, and the cell proliferation, migration, colony formation, and intracellular lactic acid and glycolytic related protein expressions were determined. Additionally, a cell model with hypoxia-induced HIF-1α expression was used and treated with apigenin. The current results displayed that the combination of apigenin and radiation could synergically reduce the viability, colony formation, and migration of the both GSCs. Moreover, this combination could also decrease the radiation-induced increments of glycolytic production lactic acid in the both GSCs and related protein expressions, including HIF-1α, glucose transporter (GLUT)-1/3, nuclear factor kappa B (NF-κB) p65, and pyruvate kinase isozyme type M2 (PKM2). Further study confirmed that after treatment of hypoxia-cultured SU3 or SU3-5R cells with apigenin, the expression levels of HIF-1α, GLUT-1/3, NF-κB p65, and PKM2 proteins were reduced. These results demonstrated that apigenin could increase the radiosensitivity of GSCs and its radiosensitization mechanisms were attributable to the attenuation of glycolysis, which might result from the inhibition of HIF-1α expression and subsequent reductions of GLUT-1/3, NF-κB, and PKM2 expressions.

Apigenin-induced HIF-1α inhibitory effect improves abnormal glucolipid metabolism in AngⅡ/hypoxia-stimulated or HIF-1α-overexpressed H9c2 cells

BACKGROUND

Apigenin, a natural flavonoid compound, can improve the myocardial abnormal glucolipid metabolism and down-regulate the myocardial hypoxia inducible factor-1α (HIF-1α) in hypertensive cardiac hypertrophic rats. However, whether or not the ameliorative effect of glucolipid metabolism is from the reduction of HIF-1α expression remains uncertain.

PURPOSE

This study aimed to investigate the exact relationship between them in angiotensin Ⅱ (Ang Ⅱ)/hypoxia-stimulated or HIF-1α overexpressed H9c2 cells.

METHODS

Two cell models with Ang Ⅱ/hypoxia-induced hypertrophy and HIF-1α overexpression were established. After treatment of the cells with different concentrations of apigenin, the levels of total protein, free fatty acids (FFA), and glucose were detected by the colorimetric method, the level of atrial natriuretic peptide (ANP) was detected by the ELISA method, and the expressions of HIF-1α, peroxisome proliferator-activated receptor α/γ (PPARα/γ), carnitine palmitoyltmnsferase-1 (CPT-1), pyruvate dehydrogenase kinase-4 (PDK-4), glycerol-3-phosphate acyltransferase genes (GPAT), and glucose transporter-4 (GLUT-4) proteins were detected by the Western blot assay.

RESULTS

Following treatment of the both model cells with apigenin 1-10 μM for 24 h, the levels of intracellular total protein, ANP, and FFA were decreased, while the level of cultured supernatant glucose was increased. Importantly, apigenin treatment could inhibit the expressions of HIF-1α, PPARγ, GPAT, and GLUT-4 proteins, and increase the expressions of PPARα, CPT-1, and PDK-4 proteins.

CONCLUSION

Apigenin could exert an ameliorative effect on abnormal glucolipid metabolism in AngⅡ/hypoxia-stimulated or HIF-1α-overexpressed H9c2 cells, and its mechanisms were associated with the inhibition of HIF-1α expression and subsequent upregulation of PPARα-mediated CPT-1 and PDK-4 expressions and downregulation of PPARγ-mediated GPAT and GLUT-4 expressions.

Stevioside attenuates isoproterenol-induced mouse myocardial fibrosis through inhibition of the myocardial NF-κB/TGF-β1/Smad signaling pathway

Stevioside, a natural glycoside compound, has many beneficial biological activities, but its protective effect on myocardial fibrosis has not been reported yet. This study aimed to investigate the effect of stevioside. The isoproterenol-induced model mice were orally given stevioside 75-300 mg kg-1 for 40 days. The results showed that after the administration of stevioside, the myocardial hydroxyproline, collagen accumulation, and protein expressions of collagen I/III, α-smooth muscle actin, transforming growth factor-β1 (TGF-β1), nuclear factor kappa B p65 (NF-κB p65), Smad2/3, and P-Smad2/3 were decreased, while the glutathione peroxidase and superoxide dismutase levels in serum and myocardial tissues and protein expressions of myocardial peroxisome proliferator-activated receptor γ (PPARγ) and Smad7 were increased. After the preincubation of isoproterenol-stimulated cardiac fibroblasts with the PPARγ antagonist GW9662, stevioside-reduced protein expressions were decreased, but stevioside-induced Smad7 was not affected. These findings demonstrated that stevioside could exert a protective effect on mouse myocardial fibrosis, and its mechanisms were associated with the increments of antioxidant ability, PPARγ activation, and Smad7 expression, which caused a synergistic inhibition of the NF-κB/TGF-β1/Smad signaling pathway.

[Clinical characteristics and T-lymphocyte subsets in 48 acquired immune deficiency syndrome patients with cytomegalovirus infections]

Objective: To investigate the clinical features and T lymphocytes subsets in patients with acquired immune deficiency syndrome (AIDS) and cytomegalovirus (CMV) infection. Methods: A total of 48 hospitalized patients with human immunodeficiency virus (HIV)-1/AIDS and CMV infections were recruited at Peking Union Medical College Hospital from Jan 2010 to Aug 2017. Their clinical features and immune function were retrospectively analyzed. Patients with only HIV/AIDS in previous study were recruited as controls. Results: All 48 patients were at C3 stage, including 36 men and 12 women. Five of them were younger than 30 years old, 33 cases within 31-50 years old, and 10 cases older than 50 years old. Thirty-five patients had CD(4)(+)T lymphocytes ≤ 50 cells/μl, 7 cases with CD(4)(+)T cells 51-100/μl, 3 cases with 101-200 cells/μl, and 3 cases over 200 cells/μl. As to CMV infections, there were 31 cases of CMV viremia, 1 case of CMV encephalitis, 1 case of CMV enteritis, 5 cases of CMV pneumonia, and 9 cases of CMV retinitis. Other opportunistic infections were also common including 16 cases of pneumocystis pneumonia, 9 cases of tuberculosis, 5 cases of syphilis, 18 cases of digestive tract fungal infections, 8 cases of pulmonary fungal infections, 2 cases of EB virus infections, 2 cases of HIV encephalopathy/progressive multifocal leukoencephalopathy (PML), 3 cases of cryptococcal meningitis, 1 case of toxoplasma infection. In group of both CMV and HIV/AIDS infections, 100% patients had inverted CD(4)(+)/CD(8)(+) ratio. The immune activation marker CD(8)(+)CD(38)(+)/CD(8)(+) was higher (61.6%-98.8%) with a median value of 91.2% in 40 patients. HLA-DR(+)CD(8)(+)/CD(8)(+), another marker for T cell activation, was 25.5%-98.0% in 44 patients with a median value of 60.3%. Thirty-six patients had both immune activation markers positive. There was no significant difference in counts of B cells, natural killer cells, CD(4)(+) T cells, CD(8)(+) T cells and immune activation subsets stratified by gender and age (P>0.05). Meanwhile, neither serum HIV viral load nor serum CMV viral load was correlated with HLA-DR(+)CD(8)(+)/CD(8)(+), CD(8)(+)CD(38)(+)/CD(8)(+), CD(4)(+)T cell counts, and CD(4)(+)/CD(8)(+) ratio in the CMV and HIV/AIDS co-infection group (all P>0.05), while HIV viral load in HIV/AIDS only group was significantly correlated with HLA-DR(+)CD(8)(+)T/CD(8)(+), CD(38)(+)CD(8)(+)/CD(8)(+), CD(4)(+) T cell counts, CD(4)(+)/CD(8)(+) ratio (r=0.473, 0.575, -0.767 and -0.678, respectively, all P<0.05). Conclusions: CMV infections develop in HIV patients with advanced stage. CMV infection can cause life-threatening multiple organ lesions, especially in those with CD(4)(+) T cells less than 100 cells/μl. It is of great importance to screen CMV-IgM, pp65 antigen, CMV DNA to make early diagnosis and treatment.

[Conventional and functional MRI features of parotid Warthin tumor: correlation with clinicopathological findings]

Objective: To assess the conventional and functional MRI features of parotid Warthin tumor (adenolymphoma) and to investigate the correlation between MRI and clinicopathological features which can provide evidence for clinical diagnosis and treatment. Methods: Sixty-seven patients with parotid Warthin tumor who were treated in the Department of Stomatology, The Fifth Clinical Medical College of Yangzhou University, Changshu No. 2 People's Hospital from June 2008 to April 2017 were included in this study. The retrospective study evaluated preoperative conventional and functional MRI features and clinicopathological findings of this group of patients. Among 67 patients (65 males, 2 females) with 92 lesions, there were 16 patients with multiple lesions and others with single lesion. Their age was (62.1±8.8) years, ranging from 42 to 84 years. According to pathological features, parotid Warthin tumor were classified into two types. Type Ⅰ was predominantly solid component which included completely solid or solid tumor with some cystic components. Type Ⅱ was predominantly cystic component which was characterized by big cyst with some solid components, and could be divided into capsule-like and scum-like cystic type, based on whether its interface of solid and cystic component was clear or not. On contrast-enhanced MRI, according to whether the lesion showed enhancement or not, solid or cystic component was defined. Results: Seventy-two lesions were located in the lower pole of the parotid gland, of which sixty-eight lesions were located in posterior inferior quadrant. In addition, sixteen lesions were located in the upper pole and four lesions in the middle. Because MRI features were consistent with pathological findings, parotid Warthin tumor were classified into solid (73) and cystic types (19). On T2WI, solid components showed isointense (92), whereas on T1WI cystic components demonstrated hyperintense (90). On contrast enhanced T1WI, solid types showed marginal vasculature sign (73), mild (69) or moderate (4) enhancement, whereas its cystic component showed no enhancement. On contrast enhanced T1WI, cystic types showed ring-like enhancement of cycle-wall and intra-cystic septal linear enhancement, whereas its solid components demonstrated mild enhancement (19). On diffusion weighted imaging, these masses demonstrated hyperintensity and lower apparent diffusion coefficient value indicating restricted diffusion (59/59). On dynamic contrast-enhanced-MRI, the masses showed "wash-out" pattern (28/29) or plateau pattern (1/29). Conclusions: Parotid Warthin tumor mainly occur in the posterior inferior quadrant of parotid gland and mostly in mid-aged or elder men. It has certain characteristics on conventional and function MRI. There is correlation between MRI and clinicopathological findings and it is useful for accurate diagnosis and treatment to understand these features.