ABSTRACT
ABSTRACT Background: Neuroblastoma is a pediatric tumor with a mortality rate of 40% in the most aggressive cases. Tumor microenvironment components as immune cells contribute to the tumor progression; thereby, the modulation of immune cells to a pro-inflammatory and antitumoral profile could potentialize the immunotherapy, a suggested approach for high-risk patients. Preview studies showed the antitumoral potential of BJcuL, a C- type lectin isolated from Bothrops jararacussu venom. It was able to induce immunomodulatory responses, promoting the rolling and adhesion of leukocytes and the activation of neutrophils. Methods: SK-N-SH cells were incubated with conditioned media (CM) obtained during the treatment of neutrophils with BJcuL and fMLP, a bacteria-derived peptide highly effective for activating neutrophil functions. Then we evaluated the effect of the same stimulation on the co-cultivation of neutrophils and SK-N-SH cells. Tumor cells were tested for viability, migration, and invasion potential. Results: In the viability assay, only neutrophils treated with BJcuL (24 h) and cultivated with SK-N-SH were cytotoxic. Migration of tumor cells decreased when incubated directly (p 0.001) or indirectly (p 0.005) with untreated neutrophils. When invasion potential was evaluated, neutrophils incubated with BJcuL reduced the total number of colonies of SK-N-SH cells following co-cultivation for 24 h (p 0.005). Treatment with CM resulted in decreased anchorage-free survival following 24 h of treatment (p 0.001). Conclusion: Data demonstrated that SK-N-SH cells maintain their migratory potential in the face of neutrophil modulation by BJcuL, but their invasive capacity was significantly reduced.
ABSTRACT
Neuroblastoma is a pediatric tumor with a mortality rate of 40% in the most aggressive cases. Tumor microenvironment components as immune cells contribute to the tumor progression; thereby, the modulation of immune cells to a pro-inflammatory and antitumoral profile could potentialize the immunotherapy, a suggested approach for high-risk patients. Preview studies showed the antitumoral potential of BJcuL, a C- type lectin isolated from Bothrops jararacussu venom. It was able to induce immunomodulatory responses, promoting the rolling and adhesion of leukocytes and the activation of neutrophils. Methods: SK-N-SH cells were incubated with conditioned media (CM) obtained during the treatment of neutrophils with BJcuL and fMLP, a bacteria-derived peptide highly effective for activating neutrophil functions. Then we evaluated the effect of the same stimulation on the co-cultivation of neutrophils and SK-N-SH cells. Tumor cells were tested for viability, migration, and invasion potential. Results: In the viability assay, only neutrophils treated with BJcuL (24 h) and cultivated with SK-N-SH were cytotoxic. Migration of tumor cells decreased when incubated directly (p < 0.001) or indirectly (p < 0.005) with untreated neutrophils. When invasion potential was evaluated, neutrophils incubated with BJcuL reduced the total number of colonies of SK-N-SH cells following co-cultivation for 24 h (p < 0.005). Treatment with CM resulted in decreased anchorage-free survival following 24 h of treatment (p < 0.001). Conclusion: Data demonstrated that SK-N-SH cells maintain their migratory potential in the face of neutrophil modulation by BJcuL, but their invasive capacity was significantly reduced.(AU)
Subject(s)
Animals , Peptides , Bothrops , Crotalid Venoms/isolation & purification , Lectins, C-Type/isolation & purification , Neuroblastoma , Neutrophils , In Vitro TechniquesABSTRACT
Objective@#To investigate the role of lysosomes in manganese-induced toxicity in human neuroblastoma SK-N-SH cells.@*Methods@#SK-N-SH cells were treated with MnCl2 at doses of 0.062 5, 0.125, 0.25, 0.5, 1.0, 2.0 and 4.0 mmol/L for 24 h, and the cell viability was detected by MTT assay. Cells were treated with MnCl2 at doses of 0.125, 0.25, 0.5 and 1.0mmol/L for 24 h, and lysosomes labeled with lysotracker red were observed by laser confocal microscopy, the expression levels of LAMP1 and CTSD were detected by western blot, and CTSD activity was detected by Cathepsin D Activity Fluorometric Assay Kit.@*Results@#Compared with the control group, the survival rates of SK-N-SH cells were decreased significantly in the 0.5-4.0 mmol/L MnCl2 treatment groups (P<0.01) , the relative fluorescence intensities of 0.5 and 1.0 mmol/L MnCl2 treatment groups were increased (P<0.01) . Compared with the control group, the 0.125-0.5 mmol/L MnCl2 treatment groups had significant increase in the the expression of LAMP1 (P<0.01) . Compared with the control group, the expression of m-CTSD was significantly increased at the does of 0.125-0.25 mmol/L MnCl2, while it was decreased at the does of 1.0 mmol/L (P<0.01) . Otherwise, it wasn’t observed significant difference of the activity of CTSD between different MnCl2 treatment groups.@*Conclusion@#MnCl2 could cause cytotoxicity in SK-N-SH cells. Lysosomes may play a normal function at low doses of manganese, but they may be damaged at high doses of manganese. As an organelle that can degradate substrates in autophagy, lysosomes participate in the neurotoxic mechanism of manganese.
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Objective@#To investigate the effect of manganese chloride (MnCl2) or 1-methyl-4-phenylpyridinium (MPP +) on oxidative stress and autophagy in human neuroblastomaSK-N-SH cells and the mechanism of the neurotoxicity of manganese.@*Methods@#SK-N-SH cells were treated with MnCl2 or MPP+ at doses of 0.062 5, 0.125, 0.25, 0.5, 1.0, and 2.0 mmol/L for 24 hours, and MTT assay was used to measure cell viability. The cells weretreated with MnCl2 or MPP+ at doses of 0.125, 0.25, and 0.5 mmol/L for 24 hours, and flow cytometry was used to measure the content of reactive oxygen species (ROS) in cells, a laser scanning confocal microscope was used to observe autophagosome in cells, and Western blot was used to measure the expression of autophagy-related proteins P62 and LC3-II/LC3-I.@*Results@#Compared with the control group, the 0.0625-2.0 mmol/L MnCl2 and 0.125-2.0 mmol/L MPP + treatment groups had significant reductions in the viability of SK-N-SH cells, and the 0.25-2.0 mmol/L MnCl2 treatment groups had significantly lower viability than the groups treated with the same doses of MPP+ (all P<0.05) . Compared with the control group, the 0.125-0.25 mmol/L MnCl2 and 0.125-0.5 mmol/L MPP+ treatment groups had significant increases in the content of ROS, and the 0.25-0.5 mmol/L MPP+ treatment groups had significantly higher content of ROS than the groups treated with the same doses of MnCl2 (all P<0.05) . Compared with the control group, the 0.25-0.5 mmol/L MnCl2 andMPP+ treatment groups had significant increases in autophagy-related proteins LC3-II/LC3-I and significant reductions in P62 expression; the 0.125-0.5 mmol/L MPP+ treatment groups had significantly higher LC3-II/LC3-I than the groups treated with the same doses of MnCl2, and the 0.125 and 0.25 mmol/L MPP + treatment groups had significantly lower P62 expression than the groups treated with the same doses of MnCl2 (all P<0.05) .@*Conclusion@#Both MnCl2 and MPP+ can induce oxidative stress and autophagy in SK-N-SH cells, and MPP+ has a significantly greater inductive effect on autophagy of SK-N-SH cells than MnCl2.
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AIM: To investigate the inhibitory effect s of a synthetic CRE-transcription factor decoy oligodeoxynucleotide (CRE-decoy ODN) on the upregulation of the expression of cholecystokinin (CCK) and fosB mRN A induced by chronic morphine administration in SK-N-SH cells. METHODS: The CRE cis-element, TGACGTCA, was palindromic, a sy nthetic single-stranded phosphorothioate oligodeoxynucleotide composed of the CR E sequence self-hybridizes to form a duplex/hairpin. The CRE-palindromic decoy a nd control oligodeoxynucleotides were added to the medium (1 h before exposure t o morphine) at 150 nmol/L in the presence of cationic lipid DOTAP. After the cel ls were treated with 100 ?mol/L morphine for 48 h, 10 ?mol/L naloxone was use d for 15 min. The effects of CRE-decoy ODN on the DNA-binding activity of CREB, the expression of CCK and fosB mRNA were detected by electrophoresis mobi lity shift assay (EMSA) and RT-PCR, respectively. The stability of cell-incorpo rated [ 32P]-labeled CRE-decoy ODN was extracted with phenol:chloroform a nd then subjected to 20% nondenaturing polyacrylamide gel electrophoresis and au toradiography. RESULTS: Chronic morphine administration and acute naloxone-prec ipitated withdrawal significantly activated the DNA-binding activity of CREB and the expression of CCK and fosB mRNA in SK-N-SH cells. The CRE-decoy ODN pen etrated into the cells, specifically downregulated these indexes. CONCLUSIONS: CRE-decoy ODN can significantly downregulates the e xpre ssion of CCK and fosB mRNA through specifically suppressing the DNA-binding activity of CREB activated by chronic morphine administration in SK-N-SH cells.