SPECT/CT imaging for tracking subendothelial retention of electronegative low-density lipoprotein in vivo.

The fifth subfraction of low-density lipoprotein (L5 LDL) can be separated from human LDL using fast-protein liquid chromatography with an anion exchange column. L5 LDL induces vascular endothelial injury both in vitro and in vivo through the lectin-like oxidized LDL receptor-1 (LOX-1). However, no in vivo evidence shows the tendency of L5 LDL deposition on vascular endothelium and links to dysfunction. This study aimed to investigate L5 LDL retention in vivo using SPECT/CT imaging, with Iodine-131 (131I)-labeled and injected into six-month-old apolipoprotein E knockout (apoE-/-) mice through tail veins. Besides, we examined the biodistribution of L5 LDL in tissues and analyzed the intracellular trafficking in human aortic endothelial cells (HAoECs) by confocal microscopy. The impacts of L5 LDL on HAoECs were analyzed using electron microscopy for mitochondrial morphology and western blotting for signaling. Results showed 131I-labeled-L5 was preferentially deposited in the heart and vessels compared to L1 LDL. Furthermore, L5 LDL was co-localized with the mitochondria and associated with mitofusin (MFN1/2) and optic atrophy protein 1 (OPA1) downregulation, leading to mitochondrial fission. In summary, L5 LDL exhibits a propensity for subendothelial retention, thereby promoting endothelial dysfunction and the formation of atherosclerotic lesions.

Sorafenib Induces Apoptosis and Inhibits NF-κB-mediated Anti-apoptotic and Metastatic Potential in Osteosarcoma Cells.

BACKGROUND/AIM: Sorafenib, an oral multi-kinase inhibitor, has been shown to improve the outcome of patients with osteosarcoma (OS). However, the anti-OS effect and mechanism of sorafenib has not yet been fully understood. The main purpose of this study was to investigate the effect of sorafenib on apoptotic signaling and Nuclear Factor-κB (NF-κB)-mediated anti-apoptotic and metastatic potential in OS in vitro. MATERIALS AND METHODS: The effect of sorafenib on apoptotic signaling transduction, anti-apoptotic, and metastatic potential of OS U-2 cells was verified with flow cytometry, trans-well invasion/migration, and western blotting assay. RESULTS: Sorafenib induced the extrinsic and intrinsic apoptotic pathways. In addition, sorafenib reduced the invasion and migration ability of OS cells, induced NF-κB activation, and the expression of anti-apoptotic proteins and metastasis-associated proteins encoded by NF-κB target genes. CONCLUSION: Sorafenib led to stimulation of extrinsic/intrinsic apoptotic pathways and NF-κB inactivation in U-2 OS cells.

Lenvatinib Induces AKT/NF-κB Inactivation, Apoptosis Signal Transduction and Growth Inhibition of Non-small Cell Lung Cancer In Vivo.

BACKGROUND/AIM: Non-small cell lung cancer (NSCLC) is the most common type of lung cancer with poor prognosis. Lenvatinib is a multi-kinase inhibitor that has the potential to suppress tumor progression. Our previous study suggested that lenvatinib induces cytotoxicity and apoptosis in CL-1-5-F4 cells in vitro. However, whether lenvatinib suppresses NSCLC progression in vivo remains unclear. MATERIALS AND METHODS: Tumor growth inhibition and normal tissue toxicity evaluation following lenvatinib treatment were performed on CL-1-5-F4-bearing mice. RESULTS: Tumor growth calculated by caliper and living cell intensity decreased by lenvatinib treatment as analysed by bioluminescence imaging. Phosphorylation of AKT, NF-κB, and NF-κB downstream proteins involved in tumor progression were reduced by lenvatinib in the tumor tissue. No pathological changes were found in the liver, kidney, and spleen after lenvatinib treatment. CONCLUSION: Induction of apoptosis and suppression of AKT/NF-κB were associated with lenvatinib-induced inhibition of the progression of NSCLC in vivo.

Preparation and Characterization of pH Sensitive Chitosan/3-Glycidyloxypropyl Trimethoxysilane (GPTMS) Hydrogels by Sol-Gel Method.

pH responsive chitosan and 3-Glycidyloxypropyl trimethoxysilane (GPTMS) hydrogels were synthesized by the sol-gel crosslinking reaction. GPTMS was introduced to influence several behaviors of the chitosan hydrogels, such as the swelling ratio, mechanical properties, swelling thermodynamics, kinetics, and expansion mechanism. The functional groups of Chitosan/GPTMS hybrid hydrogels were verified by FT-IR spectrometer. Differential scanning calorimetry (DSC) and the thermogravimetric analysis (TGA) were used to analyzed the thermal behavior of water molecules, the expansion of thermodynamics, and the content of water molecules in the hydrogel. The results show that hydrogel consists of 50 wt.% GPTMS (CG50) and has good mechanical properties and sensitivity to pH response characteristics in the acidic/alkaline buffer solution. The increase of GPTMS content leads to the increase of hydrophobic groups in the hydrogel and causes the decrease of the overall water content and the freezing bond water content. When the hydrogels were immersed in acid solution, the interaction force parameter was smaller than that of DI-water and alkaline. It means that the interaction forces between hydrogel and water molecules are relatively strong. The swelling kinetics of hybrid hydrogels were investigated to inspect the swelling mechanism. The result is consistent with the Fisk's diffusion mechanism, meaning that the rate of water penetration is adjustable. The biodegradable hydrogel (CG50) in this study has good environmental sensitivity and mechanical properties. It is suitable to be applied in the fields of drug release or biomedical technology.

Therapeutic Efficacy and Inhibitory Mechanism of Regorafenib Combined With Radiation in Colorectal Cancer.

BACKGROUND: Although both chemotherapy and radiotherapy (RT) can sufficiently maintain tumor suppression of colorectal cancer (CRC), these treatments may trigger the expression of nuclear factor kappa B (NF-κB) and compromise patients' survival. Regorafenib suppresses NF-κB activity in various tumor types. However, whether regorafenib may act as a suitable radiosensitizer to enhance therapeutic efficacy of RT remains unknown. MATERIALS AND METHODS: Here, we established a CRC-bearing animal model to investigate the therapeutic efficacy of regorafenib in combination with RT, through measurement of tumor growth, body weight, whole-body computed tomography (CT) scan and immunohisto-chemistry staining. RESULTS: Smallest tumor size and weight were found in the combination treatment group. In addition, RT-induced up-regulation of NF-κB and downstream proteins were diminished by regorafenib. Moreover, the body weight and liver pathology in the treated group were similar to those of the non-treated control group. CONCLUSION: Regorafenib may enhance the anti-CRC efficacy of RT.

Apoptosis induction and AKT/NF-κB inactivation are associated with regroafenib-inhibited tumor progression in non-small cell lung cancer in vitro and in vivo.

Non-small cell lung cancer (NSCLC) is a malignant lung cancer type with poor prognosis. NF-κB, the oncogenic transcription factor, has been recognized as an important mediator in progression of NSCLC. Regorafenib, a multikinase inhibitor, was demonstrated to inhibit tumor progression through suppression of ERK/NF-κB signaling in hepatocellular carcinoma cells in vitro and in vivo. However, whether regorafenib inhibit progression of NSCLC is ambiguous. Thus, the major purpose of present study was to evaluate anticancer efficacy and underlying mechanism of regorafenib on tumor progression in NSCLC in vitro and in vivo. CL-1-5-F4 cells were treated with regorafenib, NF-κB (QNZ) or AKT (LY294002) inhibitor for 24 or 48 h. Then, we performed cell viability assay, NF-κB reporter gene assay, transwell invasion assay and apoptosis related flow cytometry assay on cellular level to verify anti-cancer effect and mechanism of regorafenib. CL-1-5-F4 bearing animal model was treated with vehicle or regorafenib for 28 days. The therapeutic efficacy and mechanism of regorafenib in CL-1-5-F4 bearing animal model were investigated by tumor size evaluation, whole body computer tomography (CT) scan, Haemotoxylin and Eosin (H&E) stain and immunohistochemistry (IHC) stain. Our results demonstrated regorafenib significantly inhibited tumor growth and induced apoptosis through extrinsic/intrinsic pathways in NSCLC in vitro and in vivo. Furthermore, we also found the suppression of AKT/NF-κB signaling was required for regorafenib inhibited expression of progression-related and invasion-related proteins. Our finding indicated apoptosis induction and suppression of AKT/NF-κB signaling were associated with regorafenib-inhibited progression of NSCLC in vitro and in vivo.

Regorafenib inhibits tumor progression through suppression of ERK/NF-κB activation in hepatocellular carcinoma bearing mice.

Regorafenib has been demonstrated in our previous study to trigger apoptosis through suppression of extracellular signal-regulated kinase (ERK)/nuclear factor-κB (NF-κB) activation in hepatocellular carcinoma (HCC) SK-Hep1 cells in vitro However, the effect of regorafenib on NF-κB-modulated tumor progression in HCC in vivo is ambiguous. The aim of the present study is to investigate the effect of regorafenib on NF-κB-modulated tumor progression in HCC bearing mouse model. pGL4.50 luciferase reporter vector transfected SK-Hep1 (SK-Hep1/luc2) and Hep3B 2.1-7 tumor bearing mice were established and used for the present study. Mice were treated with vehicle or regorafenib (20 mg/kg/day by gavage) for 14 days. Effects of regorafenib on tumor growth and protein expression together with toxicity of regorafenib were evaluated with digital caliper and bioluminescence imaging (BLI), ex vivo Western blotting immunohistochemistry (IHC) staining, and measurement of body weight and pathological examination of liver tissue, respectively, in SK-Hep1/luc2 and Hep3B 2.1-7 tumor bearing mice. The results indicated regorafenib significantly reduced tumor growth and expression of phosphorylated ERK, NF-κB p65 (Ser536), phosphorylated AKT, and tumor progression-associated proteins. In addition, we found regorafenib induced both extrinsic and intrinsic apoptotic pathways. Body weight and liver morphology were not affected by regorafenib treatment. Our findings present the mechanism of tumor progression inhibition by regorafenib is linked to suppression of ERK/NF-κB signaling in SK-Hep1/luc2 and Hep3B 2.1-7 tumor bearing mice.

Hyperforin Inhibits Cell Growth by Inducing Intrinsic and Extrinsic Apoptotic Pathways in Hepatocellular Carcinoma Cells.

The aim of the present study was to investigate the antitumor effect and mechanism of action of hyperforin in hepatocellular carcinoma (HCC) SK-Hep1 cells in vitro. Cells were treated with different concentrations of hyperforin for different periods of time. Effects of hyperforin on cell viability, apoptosis signaling, and expression of anti-apoptotic and proliferative proteins [cellular FLICE-like inhibitory protein (c-FLIP), X-linked inhibitor of apoptosis protein (XIAP), myeloid cell leukemia 1(MCL1), and cyclin-D1] were investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, flow cytometry, and western blotting. Hyperforin significantly inhibited cell viability and expression of anti-apoptotic and proliferative proteins. We also found that hyperforin significantly induced accumulation of cells in sub-G1 phase, loss of mitochondrial membrane potential, and increased levels of active caspase-3, and caspase-8. Taken together, our findings indicate that hyperforin triggers inhibition of tumor cell growth by inducing intrinsic and extrinsic apoptotic pathways in HCC SK-Hep1 cells.