Lung cancer is the leading cause of cancer-related deaths worldwide. Despite the development and use of several targeting drugs for lung cancer therapy, the five-year survival rate has remained as low as 15% for the past three decades. Cisplatin-based chemotherapy is considered the first-line therapeutic strategy for lung cancer. However, developments of chemoresistance is a major obstacle for the successful treatment. Therefore, the development of novel therapy against cisplatin-resistance lung cancer is imperative. Photodynamic therapy (PDT), which is a non-invasive combinatorial therapeutic modality using light, photosensitizer (PS) and oxygen, may provide an unprecedented tool to develop more effective treatments. To provide experimental basis for its application in cisplatin-resistance lung cancer, we will discuss the biological effects of MPPa-photodynamic therapy in human cisplatin-resistance lung cancer cells in this article. Human cisplatin-resistance lung cancer cells A549/DDP were co-cultured with MPPa (0, 1, 2, 4, 8, 16 μmol/L) and exposed to light (0, 0.6, 1.2, 2.4, 3.6, 4.8 J/cm2), and cell viability was determined with CCK-8 assay. Flow cytometry was used to detect apoptosis, DCFH-DA staining was employed to observe reactive oxygen species (ROS), and Western blot was used to detect the expressions of B-cell lymphoma-2 (Bcl-2) protein and Bcl-2 associated X protein (Bax). The proliferation of A549/DDP cells was suppressed by PDT. The apop-totic rate in the PDT group was significantly higher than that in the control, MPPa or light group (P < 0.05). The level of ROS was increased. The expression of Bax was increased, and that of Bcl-2 was decreased. MPPa-photodynamic therapy can significantly suppress cell viability, and induce apoptosis in human cisplatin-resistance lung cancer cells.
To aggressively proliferate and metastasize, cancer cells are in extreme need of energy supply and nutrients. Therefore, a promising cancer therapy strategy is developed to target its hallmark feature of metabolism. Recent findings revealed the regulatory role of caveolin-1 (Cav-1), a structural protein of caveolae, in cancer metabolism. And low Cav-1 expression in tumor stroma was proved to be a central player of cancer malignant phenotype. Here, we summarized the progressions of studies on Cav-1, mitochondria and cancer metabolism to indicate that the altered metabolism induced by Cav-1 and mitochondria association is a major cause of cancer malignant phenotype.
Objective To investigate the protective effect of the antioxidant glutathione (GSH) on the steroid-induced imbalance between osteogenesis and adipogenesis in human bone marrow mesenchymal stem cells (BMSCs). Methods The BMSCs were isolated from the proximal femur bone marrow from 3 patients of femoral neck fracture and were separated, cultured, and purificated by density gradient centrifugation and adherent wall methodin vitro. The third generation BMSCs were divided into 5 groups: group A, BMSCs (1×105 cells/mL); group B, BMSCs (1×105 cells/mL)+10 μmol/L dexamethasone; group C, BMSCs (1×105 cells/mL)+10 μmol/L dexamethasone+5 μmol/L GSH; group D, BMSCs (1×105 cells/mL)+10 μmol/L dexamethasone+10 μmol/L GSH; group E, BMSCs (1×105 cells/mL)+10 μmol/L dexamethasone+50 μmol/L GSH. After cultured for 7 days, the reactive oxygen species expression was detected by flow cytometry; the superoxide dismutase (SOD) and Catalase mRNA expressions were determined by RT-PCR; the peroxisome proliferator-activated receptors γ (PPAR-γ), CCAAT/enhancer-binding family of proteins (C/EBP), Runx2, and alkaline phosphatase (ALP) mRNA expressions were evaluated by real-time fluorescence quantitative PCR. After cultured for 21 days, Oil red O staining was used to observe the adipogenesis differentiation of cells, and the expressions of related proteins were detected by Western blot. Results The reactive oxygen species expression in group B was obviously higher than in the other groups, in group C than in groups A, D, and E, and in groups D, E than in group A, all showing significant differences between groups (P<0.05); but there was no significant difference between groups D and E (P>0.05). The oil red O staining positive cells in group B were obviously more than the other groups, and groups C, D, E, and A decreased sequentially, the absorbance (A) values had significant differences between groups (P<0.05). RT-PCR detection showed that the relative expressions of SOD and Catalase mRNA in group B were significantly lower than those in the other groups, while in group C than in groups A, D, and E (P<0.05), but there was no significant difference among groups A, D, and E (P>0.05). Real-time fluorescence quantitative PCR detection showed that the relative expressions of PPAR-γ and C/EBP mRNA in group B were significantly higher than those in the other groups, while in group C than in groups A, D, and E, and in groups D, E than in group A (P<0.05); but there was no significant difference between groups D and E (P>0.05). The relative expressions of Runx2 and ALP mRNA in group B were significantly lower than those in the other groups, while in group C than in groups A, D, and E, and in groups D, E than in group A (P<0.05); but there was no significant difference between groups D and E (P>0.05). Western blot detection showed that the relative expression of PPAR-γ and C/EBP protein in group B was significantly higher than those in the other groups, and groups C, D, E, and A decreased sequentially, all showing significant differences between groups (P<0.05). The relative expression of Runx2 and ALP protein in group B was significantly lower than those in the other groups, and groups C, D, E, and A increased sequentially, all showing significant differences between groups (P<0.05). Conclusions GSH can inhibit the adipogenesis differentiation and enhance the osteogenic differentiation of human BMSCs by reducing the intracellular reactive oxygen species level; and in a certain range, the higher the concentration of GSH, the more obvious the effect is.
ObjectiveTo investigate the role of p22phox and NOX5 in autophagy and apoptosis of osteoblasts induced by hypoxia.MethodsThe skull tissue of newborn rats was cut into small pieces, and the osteoblasts were separated and purified by the tissue block adherent method and the differential adherent method. The first generation cells were harvested and identified by HE staining, Alizarin red staining, alkaline phosphatase (ALP) staining, and flow cytometry. A three-gas incubator was used to prepare a hypoxia model of osteoblasts. At 0, 3, 6, 12, and 24 hours of hypoxia, the expressions of p22phox, NOX5, and LC3Ⅱ/Ⅰ were detected by Western blot, and the level of reactive oxygen species (ROS) and cell apoptosis rate were detected by flow cytometry. And the time point of the highest level of ROS was selected as the hypoxia time point for subsequent experiments. The first generation osteoblasts were divided into normal group, si-p22phox hypoxia group, and si-NOX5 hypoxia group and subjected to corresponding transfection and hypoxia treatment. The inhibition efficiency of si-p22phox and si-NOX5 were detected by RT-PCR. Then the osteoblasts were divided into normal group, si-NC hypoxia group, si-p22phox hypoxia group, and si-NOX5 hypoxia group. After transfection and hypoxia treatment, Western blot was used to detect the expressions of p22phox, NOX5, autophagy-related proteins (LC3Ⅱ/Ⅰ, Beclin), and apoptosis-related proteins (Bcl-2, Bax), and flow cytometry was used to detect the cell apoptosis rate and level of ROS. The first generation osteoblasts were divided into a hypoxia group for 12 hours (hypoxia group) and a group that simultaneously inhibited si-p22phox and si-NOX5 and hypoxia for 12 hours (inhibition+hypoxia group). The expressions of Beclin and Bax were observed by immunofluorescence staining after the corresponding treatment.ResultsAfter identification, the isolated cells were osteoblasts. After hypoxia treatment, the relative expressions of p22phox, NOX5, and LC3Ⅱ/Ⅰ proteins and the apoptosis rate of osteoblasts gradually increased (P<0.05), and the level of ROS also significantly increased (P<0.05) and reached the peak value at 12 hours. The 12-hour hypoxia model was selected for subsequent experiments. Silencing the p22phox gene did not affect the expression of NOX5, and silencing the NOX5 gene did not affect the expression of p22phox. Compared with hypoxia treatment, the relative expressions of LC3Ⅱ/Ⅰ, Beclin, and Bax proteins after inhibiting the expression of p22phox or NOX5 gene significantly decreased (P<0.05), the relative expression of Bcl-2 protein significantly increased (P<0.05), the cell apoptosis rate and level of ROS also significantly decreased (P<0.05). After silencing the expressions of p22phox and NOX5 genes at the same time, the immunofluorescence staining showed that the fluorescence of Beclin and Bax were weak.ConclusionInhibiting the expressions of p22phox and NOX5 genes can reduce the level of ROS in osteoblasts under hypoxia-induced conditions, and at the same time reduce autophagy and apoptosis, especially attenuate the excessive apoptosis of cells in the early to late stages, and strengthen the hypoxic osteoblasts proliferation.
ObjectiveGelatin methacryloyl (GelMA)/hyaluronic acid methacryloyl (HAMA)/chitosan oligosaccharide (COS) hydrogel was used to construct islet biomimetic microenvironment, and to explore the improvement effect of GelMA/HAMA/COS on islet activity and function under hypoxia. Methods Islets cultured on the tissue culture plate was set as the control group, on the GelMA/HAMA/COS hydrogel with COS concentrations of 0, 1, 5, 10, and 20 mg/mL respectively as the experimental groups. Scanning electron microscopy was used to observe the microscopic morphology, rheometer test to evaluate the gel-forming properties, contact angle to detect the hydrophilicity, and the biocompatibility was evaluated by the scaffold extract to L929 cells [using cell counting kit 8 (CCK-8) assay]. The islets were extracted from the pancreas of 8-week-old Sprague Dawley rats and the islet purity and function were identified by dithizone staining and glucose-stimulated insulin secretion (GSIS) assays, respectively. Islets were cultured under hypoxia (1%O2) for 24, 48, and 72 hours, respectively. Calcein-acetyl methyl/propidium iodide (Calcein-AM/PI) staining was used to evaluate the effect of hypoxia on islet viability. Islets were cultured in GelMA/HAMA/COS hydrogels with different COS concentrations for 48 hours, and the reactive oxygen species kits were used to evaluate the antagonism of COS against islet reactive oxygen species production under normoxia (20%O2) and hypoxia (1%O2) conditions. Calcein-AM/PI staining was used to evaluate the effect of COS on islet activity under hypoxia (1%O2) conditions. Islets were cultured in tissue culture plates (group A), GelMA/HAMA hydrogels (group B), and GelMA/HAMA/COS hydrogels (group C) for 48 hours, respectively. Immunofluorescence and GSIS assays were used to evaluate the effect of COS on islet activity under hypoxia (1%O2) conditions, respectively. Results GelMA/HAMA/COS hydrogel had a porous structure, the rheometer test showed that it had good gel-forming properties, and the contact angle test showed good hydrophilicity. CCK-8 assay showed that the hydrogel in each group had good biocompatibility. The isolated rat islets were almost round, with high islet purity and insulin secretion ability. Islets were treated with hypoxia for 24, 48, and 72 hours, Calcein-AM/PI staining showed that the number of dead cells gradually increased with time, which were significantly higher than those in the non-hypoxia-treated group (P<0.001). Reactive oxygen staining showed that GelMA/HAMA/COS hydrogels with different COS concentrations could antagonize the production of reactive oxygen under normal oxygen and hypoxia conditions, and this ability was positively correlated with COS concentration. Calcein-AM/PI staining indicated that GelMA/HAMA/COS hydrogels with different COS concentrations could improve islet viability under hypoxia conditions, and cell viability was positively correlated with COS concentration. Immunofluorescence staining showed that GelMA/HAMA/COS hydrogel could promote the expression of islet function-related genes under hypoxia conditions. GSIS assay results showed that the insulin secretion of islets in hypoxia condition of group C was significantly higher than that of groups B and C (P<0.05). Conclusion GelMA/HAMA/COS hydrogel has good biocompatibility, promotes islet survival and function by inhibiting reactive oxygen species, and is an ideal carrier for building islet biomimetic microenvironment for islet culture and transplantation.
ObjectiveTo investigate the molecular mechanism by which metastasis-associated protein 3 (MTA3) participates in glioma resistance through reactive oxygen species. Methods Protein expression in glioma stem cells (GSCs) and non-GSCs was detected using Western blotting. GSCs included U87 and SHG44 cells, while non-GSCs included U87s and SU-2 cells. After overexpressing MTA3, U87 and SHG44 cells were divided into Lv-scr and Lv-MTA3 groups. The self-renewal capacity of glioma cells was assessed through a neurosphere formation assay. Cell survival fractions were examined following exposure to 0, 2, 4, 6, 8, and 10 Gy X-ray irradiation under normoxic or hypoxic conditions. Apoptosis and reactive oxygen species expression were analyzed using flow cytometry. Immunofluorescence staining was performed to detect the stem cell markers CD133 and nestin, as well as the differentiation markers glial fibrillary acidic protein (GFAP, for astrocytes) and neuronal class Ⅲ β-tubulin. Results In GSCs, MTA3 expression was lower in the U87s and SU-2 groups. After MTA3 overexpression, Lv-MTA3 expression was higher in U87s and SU-2 compared to the Lv-scr group. Under normoxic or hypoxic conditions, U87 and SU-2 showed greater radioresistance compared to glioma cell lines U87 and SHG44. Compared to non-GSCs, basal reactive oxygen species formation was reduced in GSCs, while reactive oxygen species generation was increased in non-GSCs. Following exposure to different doses of X-rays under normoxic or hypoxic conditions, GSCs with MTA3 overexpression exhibited greater radiosensitivity than those with stable integration. Additionally, MTA3 overexpression slightly increased the oxygen enhancement ratio (OER) in GSCs. MTA3 overexpression reduced the immunoreactivity of CD133 and nestin in both stem cell lines, and increased immunofluorescence staining of GFAP and neuronal class Ⅲ β-tubulin, with statistically significant differences (P<0.05). Conclusions MTA3 is downregulated in GSCs. Overexpression of MTA3 reduces the radioresistance and stemness of GSCs both in vitro and in vivo. MTA3 plays a crucial role in regulating the radiosensitivity and stemness of GSCs through reactive oxygen species.
Objective To investigate the in vitro antioxidant and osteogenic induction capabilities of calcium phosphate nanoflowers (hereinafter referred to as nanoflowers) at different concentrations. Methods Nanoflowers were prepared using gelatin, tripolyphosphate, and calcium chloride. Their morphology, microstructure, elemental composition and distribution, diameter, and molecular constitution were characterized using scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, and energy-dispersive spectroscopy. Femurs and tibias were harvested from twelve 4-week-old Sprague Dawley rats, and bone marrow mesenchymal stem cells (BMSCs) were isolated and cultured using the whole bone marrow adherent method, followed by passaging. The third passage cells were identified as stem cells by flow cytometry and then co-cultured with nanoflowers at concentrations of 0, 0.4, 0.8, 1.2, 1.6, 2.0, 2.4, 2.8, 3.2, and 3.6 mg/mL. Cell counting kit 8 (CCK-8) assay was performed to screen for the optimal concentration that demonstrated the best cell viability, which was subsequently used as the experimental concentration for further studies. After co-culturing BMSCs with the screened concentration of nanoflowers, the biocompatibility of the nanoflowers was verified through live/dead cell staining, scratch assay, and cytoskeleton staining. The antioxidant capacity was assessed by using reactive oxygen species (ROS) fluorescence staining. The in vitro osteoinductive ability was evaluated via alkaline phosphatase (ALP) staining, alizarin red staining, and immunofluorescence staining of osteocalcin (OCN) and Runt-related transcription factor 2 (RUNX2). All the above indicators were compared with the control group of normally cultured BMSCs without the addition of nanoflowers. Results Scanning electron microscopy revealed that the prepared nanoflowers exhibited a flower-like structure; transmission electron microscopy scans discovered that the nanoflowers possessed a multi-layered structure, and high-magnification images displayed continuous atomic arrangements, with the nanoflower diameter measuring (2.00±0.25) μm; energy-dispersive spectroscopy indicated that the nanoflowers contained elements such as C, N, O, P, and Ca, which were uniformly distributed across the flower region; Fourier transform infrared spectroscopy analyzed the absorption peaks of each component, demonstrating the successful preparation of the nanoflowers. Through CCK-8 screening, the concentrations of 0.8, 1.2, and 1.6 mg/mL were selected for subsequent experiments. The live/dead cell staining showed that nanoflowers at different concentrations exhibited good cell compatibility, with the 1.2 mg/mL concentration being the best (P<0.05). The scratch assay results indicated that the cell migration ability in the 1.2 mg/mL group was superior to the other three groups (P<0.05). The cytoskeleton staining revealed that the cell morphology was well-extended in all concentration groups, with no significant difference compared to the control group. The ROS fluorescence staining demonstrated that the ROS fluorescence in all concentration groups decreased compared to the control group after lipopolysaccharide induction (P<0.05), with the 1.2 mg/mL group showing the weakest fluorescence. The ALP staining showed blue-purple nodular deposits around the cells in all groups, with the 1.2 mg/mL group being significantly more prominent. The alizarin red staining displayed orange-red mineralized nodules around the cells in all groups, with the 1.2 mg/mL group having more and denser nodules. The immunofluorescence staining revealed that the expressions of RUNX2 and OCN proteins in all concentration groups increased compared to the control group, with the 1.2 mg/mL group showing the strongest protein expression (P<0.05). Conclusion The study successfully prepares nanoflowers, among which the 1.2 mg/mL nanoflowers exhibits excellent cell compatibility, antioxidant properties, and osteogenic induction capability, demonstrating their potential as an artificial bone substitute material.