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Glioma is the leading cancer of the central nervous system (CNS). The efficacy of glioma treatment is significantly hindered by the presence of the blood-brain barrier (BBB) and blood-brain tumour barrier (BBTB), which prevent most drugs from entering the brain and tumours. Hence, we established a novel drug delivery nanosystem of brain tumour-targeting that could self-assemble the method using an amphiphilic Zein protein isolated from corn. Zein's amphiphilicity prompted it to self-assembled into NPs, efficiently containing TMZ. This allowed us to investigate temozolomide (TMZ) for glioblastoma (GBM) treatment. To construct TMZ-encapsulated NPs (TMZ@RVG-Zein NPs), the NPs' Zein was clocked to rabies virus glycoprotein 29 (RVG29). To verify that the NPs could penetrate the BBB and precisely target and kill the GBM cancer cell line, in vitro studies were performed. The process of NPs penetrating cancer cell membranes was investigated using enzyme-linked immunosorbent assays (ELISAs) to measure the expressions of nicotinic acetylcholine receptors (nAChRs) on the U87 cell line. Therefore, effective targeted brain cancer treatment is possible by forming NP clocks, a cell-penetrating natural Zein protein with an RVG29. These NPs can penetrate the blood-brain barrier (BBB) and enter the glioblastoma (U87) cell line to release TMZ. These NPs have a distinct cocktail of biocompatibility and brain-targeting abilities, making them ideal for involving brain diseases.

Background miRNAs play an important role in the pathogenesis of intervertebral disc degeneration (IDD). The role and the underlying mechanism of miR-424-5p in human nucleus pulposus (NP) are still unknown. We aimed to explore the role of miR-424-5p in IDD. Methods Real-time PCR was used to detect the expression of miR-424-5p and Bcl2 in IDD tissues and idiopathic scoliosis tissues. Human NP cells were used in our study. MTT and Hoechst apoptosis assays were used to detect the proliferation and apoptosis of NP cells, respectively. Western blotting assays were used to detect the expression levels of Bcl-2, cleaved caspase-3, cleaved caspase-9, caspase-3 and caspase-9 in degenerative NP cells. A luciferase reporter assay was applied to confirm the relationship between miR-424-5p and Bcl2. Results Our results showed that the expression of miR-424-5p was increased and Bcl2 was decreased in degenerative NP cells. miR-425-5p expression was negatively correlated with Bcl2 expression in IDD tissues. Suppression of miR-424-5p using an inhibitor increased Bcl2 expression at both the mRNA and protein levels, and it promoted cell viability and inhibited apoptosis. Furthermore, the levels of cleaved caspase-3 and cleaved caspase-9 were downregulated in miR-424-5p-silenced NP cells. Interestingly, we found that silencing miR-424-5p increased p62 expression at both the mRNA and protein levels. Finally, a luciferase reporter assay verified the binding of the miR-424-5p and the 3’UTR of Bcl2. Conclusion These results suggested that silencing miR-424-5p suppressed NP cell apoptosis by upregulating Bcl2. Therefore, miR-424-5p might be a novel target for IDD therapies.

The mechanisms underlying neutrophilic inflammation in chronic rhinosinusitis with nasal polyps (CRSwNP) remain poorly investigated. This study aimed to examine the factors that contribute to tissue neutrophilia in CRSwNP. The numbers of neutrophils and active caspase-3-positive apoptotic neutrophils in sinonasal tissues were assessed via immunofluorescence staining. The 95th percentile of tissue neutrophil numbers in control subjects was selected as a cut-off to define neutrophil-high (Neu-high) or neutrophil-low (Neu-low) nasal polyps (NPs). The levels of 34 inflammatory mediators in sinonasal tissues were analyzed using Bio-Plex assay. Purified human peripheral blood neutrophils were incubated with nasal tissue homogenates, and the apoptotic neutrophils were assessed via flow cytometry. The cut-off for Neu-high NPs was >10 myeloperoxidase positive cells/high-power field. Compared with Neu-low NPs, Neu-high NPs had higher tissue levels of IL-1β, IL-1Ra, IL-6, IL-8, G-CSF, MCP-1, and MIP-1α, but lower levels of IL-5, IL-13, IgE, and eosinophils. Principal component and multiple correspondence analyses revealed mixed type 1, type 2, and type 3 endotypes for Neu-low NPs, and predominant type 1 and type 3 endotypes for Neu-high NPs. Neu-high NPs had lower percentages of apoptotic neutrophils than Neu-low NPs. The numbers of neutrophils and the percentages of apoptotic neutrophils correlated with G-CSF and IL-6 levels in the NPs. Tissue homogenates from Neu-high NPs, but not those from Neu-low NPs, suppressed neutrophil apoptosis in vitro, which was reversed by anti-G-CSF treatment. Tissue neutrophil numbers were associated with difficult-to-treat disease in patients with CRSwNP after surgery. We propose that G-CSF promotes neutrophilic inflammation by inhibiting neutrophil apoptosis in CRSwNP.

The mechanisms underlying neutrophilic inflammation in chronic rhinosinusitis with nasal polyps (CRSwNP) remain poorly investigated. This study aimed to examine the factors that contribute to tissue neutrophilia in CRSwNP. The numbers of neutrophils and active caspase-3-positive apoptotic neutrophils in sinonasal tissues were assessed via immunofluorescence staining. The 95th percentile of tissue neutrophil numbers in control subjects was selected as a cut-off to define neutrophil-high (Neu-high) or neutrophil-low (Neu-low) nasal polyps (NPs). The levels of 34 inflammatory mediators in sinonasal tissues were analyzed using Bio-Plex assay. Purified human peripheral blood neutrophils were incubated with nasal tissue homogenates, and the apoptotic neutrophils were assessed via flow cytometry. The cut-off for Neu-high NPs was >10 myeloperoxidase positive cells/high-power field. Compared with Neu-low NPs, Neu-high NPs had higher tissue levels of IL-1β, IL-1Ra, IL-6, IL-8, G-CSF, MCP-1, and MIP-1α, but lower levels of IL-5, IL-13, IgE, and eosinophils. Principal component and multiple correspondence analyses revealed mixed type 1, type 2, and type 3 endotypes for Neu-low NPs, and predominant type 1 and type 3 endotypes for Neu-high NPs. Neu-high NPs had lower percentages of apoptotic neutrophils than Neu-low NPs. The numbers of neutrophils and the percentages of apoptotic neutrophils correlated with G-CSF and IL-6 levels in the NPs. Tissue homogenates from Neu-high NPs, but not those from Neu-low NPs, suppressed neutrophil apoptosis in vitro, which was reversed by anti-G-CSF treatment. Tissue neutrophil numbers were associated with difficult-to-treat disease in patients with CRSwNP after surgery. We propose that G-CSF promotes neutrophilic inflammation by inhibiting neutrophil apoptosis in CRSwNP. [ABSTRACT FROM AUTHOR]

Chronic pancreatitis is a progressive disease characterized by irreversible morphological changes to the pancreas, typically causing pain and permanent loss of function. It is a poorly understood disease with the pathogenesis remaining unclear. The authors' previous data demonstrated that the inhibition of Toll‑like receptor 4 (TLR4) using TLR4 antagonist kinase (TAK)‑242 attenuates taurocholate‑induced oxidative stress via the regulation of mitochondrial function in the pancreatic acinar cells of mice. In the present study, the effect of TAK‑242 on trinitrobenzene sulfonic acid (TNBS)‑induced chronic pancreatitis was investigated in rats. The results revealed that TAK‑242 attenuated the severity of chronic pancreatic injury, and regulated extracellular matrix secretion and cellular immunity. In addition, TAK‑242 treatment significantly decreased cell apoptosis, as evidenced by the reduction in Terminal deoxynucleotidyl transferase dUTP nick end labeling‑positive cells in pancreas tissue sections, and also promoted cell proliferation in TNBS‑treated animals. Furthermore, the results of the calibrated von Frey filament assay demonstrated that TAK‑242 could prevent the pancreatitis‑induced referred abdominal hypersensitivity. In summary, TAK‑242 exhibits protective effects against TNBS‑induced chronic pancreatitis and may be a potential therapeutic strategy for the treatment of patients with chronic pancreatitis. [ABSTRACT FROM AUTHOR]

Gossypol is a polyphenolic, yellowish compound derived from cottonseed extract. The present study examined the effects of gossypol on the apoptosis and autophagy of HT-29 cells. A Cell Counting Kit-8 assay, Annexin V-FITC, JC-1 staining and western blotting were used to identify the viability of cells, stages of apoptosis and the expression levels of the signaling proteins. Gossypol promoted apoptosis and induced the loss of mitochondrial membrane potential. Further investigation of the apoptotic mechanism revealed that gossypol increased the ratio of B-cell lymphoma 2 (Bcl-2)-associated X protein/Bcl-2 protein levels and upregulated the expression of caspase-3. Gossypol also enhanced the activity of microtubule-associated protein light chain 3 LC3-II and Beclin-1 and downregulated LC3-I, in a dose-dependent manner. Together, these finding suggested that gossypol may be a novel and potential antitumor agent. [ABSTRACT FROM AUTHOR]

The cysteine protease cathepsin B (Cat B) is important in the progression of tumor cells, however, the function and molecular mechanisms of Cat B in hepatocellular carcinoma (HCC) remain to be elucidated. Our previous study demonstrated that integrin αvβ3 regulated the biological behavior of HCC. The present study demonstrated that Cat B was also important in cell proliferation and apoptosis in HCC. Notably, Cat B was observed to activate the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway to promote HCC proliferation. Furthermore, inhibition of integrin αvβ3 significantly prevented Cat B-induced activation of PI3K/Akt and the progression of HCC. Thus, the results of the present study suggested the presence of a Cat B/integrin αvβ3/PI3K/Akt axis in the regulation of the progression of HCC. [ABSTRACT FROM AUTHOR]

Background: Zuo-Jin-Wan (ZJW), a traditional Chinese medicine formula, has been identified to be effective against drug resistance in cancer. In the present study, we investigated the effect of ZJW on acquired oxaliplatin-resistant and the PI3K/Akt/NF-κB pathway in vitro. Methods: We tested the dose--response relationship of ZJW on reversing drug-resistance by CCK-8 assay and flow cytometry analysis in vitro. The protein expression of P-gp, MRP-2, LRP, and ABCB1 mRNA expression level were evaluated by Western blot and quantitative RT-PCR. The activities of PI3K/Akt/NF-κB pathway were also examined with or without ZJW, including Akt, IκB, p65 and their phosphorylation expression. Results: We found that ZJW significantly enhanced the sensitivity of chemotherapeutic drugs and increased oxaliplatin (L-OHP)-induced cell apoptosis in a time- and dose-dependent manner. Moreover, both ZJW and a PI3K specific inhibitor (LY294002) suppressed phosphorylation of Akt (Ser473) and NF-κB, which is necessary in the activation of the PI3K/Akt/NF-κB pathway. The effect of ZJW in reversing drug-resistance and suppressing phosphorylation of Akt (Ser473) and NF-κB were weakened after treatment with a PI3K/Akt activator in HCT116/L-OHP cells. Conclusions: Our study has provided the first direct evidence that ZJW reverses drug-resistance in human colorectal cancer by blocking the PI3K/Akt/NF-κB signaling pathway, and could be considered as a useful drug for cancer therapy. [ABSTRACT FROM AUTHOR]

JKA97, a benzylidene analog of harmine, has been found to be a promising drug candidate for human cancer therapy, although the underlying molecular mechanisms have not been fully demonstrated. In this study, we evaluated the effects of JKA97 on human breast cancer cells in vitro and in vivo. JKA97 inhibited the growth and proliferation of MCF7 (p53 wildtype), MCF7 (p53 knockdown), and MDA-MB-468 (p53 mutant) cells in a dose-dependent manner. Treatment with JKA97 arrested breast cancer cells in G1 phase and induced apoptosis. JKA97 also significantly suppressed the growth of MCF7 and MDA-MB-468 xenograft tumors. It regulated the expression levels of G1 phase regulators, such as p21, p27, cyclinE, and cylinD1. JKA97 activated p21 transcription, independent of p53, but had little effect on p21 protein stability/degradation. In summary, our results suggest that JKA97 inhibits human breast cancer cell growth through activating p21, independent of p53, which provides a basis for developing this compound as a novel drug for human breast cancer therapy. [ABSTRACT FROM AUTHOR]

We recently isolated an exon-4-deleted epidermal growth factor receptor (EGFR) variant, termed de4 EGFR. Because the extracellular domain alteration of receptors often influences the antitumor effect of therapeutic antibodies, it is essential to test the sensitivity of de4 EGFR+ tumors to anti-EGFR antibodies. Therefore, in this study, the antitumor activities of mAb CH12, an anti-EGFRvIII antibody developed in our laboratory, as well as a U.S. Food and Drug Administration-approved anti-EGFR antibody, cetuximab (C225), were characterized on de4 EGFR+ models. The results of FACS assays showed that CH12 bound to de4 EGFR with a higher avidity than did C225. Interestingly, CH12, but not C225, significantly inhibited the metastasis and growth of U87MG-de4 EGFR xenografts, with a growth-inhibition ratio of 46.48% in vivo, and prolonged the survival of the tumor-bearing mice by 37.2%. Treatment with CH12 significantly suppressed tumor proliferation and angiogenesis with increased tumor apoptosis. Mechanistically, de4 EGFR protein expression was virtually undetectable in the U87MG-de4 EGFR xenografts treated with CH12. This may account for the observed reduction of Akt and Erk phosphorylation, cyclin D1, Bcl-2, and Bcl-xL expression and the increase of p27 and E-cadherin expression. Intriguingly, LAMP-1, a major component of the lysosome, was significantly up-regulated in the CH12- treated group but not in the C225-treated group, suggesting its contribution to the degradation of de4 EGFR. Taken together, our data demonstrated that mAb CH12 is a promising therapeutic agent for treating de4 EGFR+ gliomas. [ABSTRACT FROM AUTHOR]

Caspase-12 has been localized to endoplasmic reticulum (ER) and showed to involve ER stress-induced apoptosis. In the present work we investigated the temporospatial alterations of caspase-12 immunoreactivity in the penumbra following cerebral ischemia/reperfusion in rabbit. Transient cerebral ischemia was produced by intraluminal occlusion of the middle cerebral artery for 2 h followed by 1 h, 6 h, 1 day, 3 days, 7 days and 14 days of reperfusion. Caspase-12 immunohistochemistry was first increased in the penumbra 1 h after reperfusion, with a peak at day 1 to day 3, and then gradually decreased to basal level at day 14. The number of TUNEL-positive cells and ultrastructural observation of brain sections in the penumbra showed a similar change at the same time points. ER mediated by caspase-12 participated in apoptosis induced by cerebral ischemia/reperfusion injury, which may provide a new area for therapeutic intervention to ameliorate outcomes following cerebral ischemia. [ABSTRACT FROM AUTHOR]

Two groups of rats were used to examine the effect of pioglitazone, a peroxisome proliferator-activated receptor γ (PPARγ) agonist, on rat hearts using an in vivo model of ischemia-reperfusion (I/R) to elucidate potential mechanisms. One group was the 30-min reperfusion group, which was further subdivided into sham (n = 5), vehicle (n = 6) and pioglitazone (3 mg·kg–1, n = 7) treatment groups with 30 min ischemia followed by 30 min reperfusion to detect data related to cardiac function and the area of myocardial infarction. The other group was the 120-min reperfusion group, subdivided into sham (n = 5), vehicle (n = 6), and pioglitazone 0.3 mg·kg–1 (n = 6), 1 mg·kg–1 (n = 7) and 3 mg·kg–1 (n = 6) treatment groups. Immunohistochemistry, in situ hybridization, terminal deoxynucleotidyltransferase-mediated dUTP-biotin nick end labeling (TUNEL) and DNA agarose gel electrophoresis were performed to detect apoptosis and expressions of Bax, Bcl-2, caspase 3, MMP-2 and PPARγ protein, and MMP-2 and PPARγ mRNA. We found that, after acute treatment with pioglitazone, the ratio of necrosis to area at risk decreased by 28% (p < 0.01) and that of necrosis to left ventricle was reduced by 32% (p < 0.01), compared with the vehicle group. Heart rate and +dp/dtmax, representing the cardiac systolic function, as well as –dp/dtmax, the indicator of cardiac diastolic function, improved significantly at 1 and 30 min after reperfusion (p < 0.05–0.01). Furthermore, myocardial apoptosis was significantly suppressed by acute treatment with pioglitazone as evidenced by the decreased number of TUNEL-positive myocytes and DNA ladder, enhanced Bcl-2 protein expression, reduced Bax and caspase 3 protein expression in a dose-dependent manner compared with vehicle-treated rats. In addition, acute treatment with pioglitazone dose-dependently increased PPARγ expression and decreased MMP-2 expression at protein and mRNA levels. Our findings demonstrate that a PPARγ agonist may protect the heart from I/R injury. The protective effect is likely to occur by reducing cardiomyocyte apoptosis and inhibiting MMP-2. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The RON (recepteur d'origine nantais) receptor belongs to the MET proto-oncogene family that is implicated in the oncogenesis of the gastrointestinal epithelium. The present study aimed to determine the role of RON in regulating epithelial phenotypes in response to transforming growth factor (TGF)-1. Expression and activation of RON in SV40-immortalized mouse intestinal epithelial MODE-K cells result in reduction of cellular sensitivities towards apoptotic signals elicited by TGF-1. This effect is dependent on RON expression and phosphorylation that inhibit the TGF-1-induced activation of caspase-3 and truncation of BAD. Among cellular signaling components, the activation of MAP kinase is critical in the RON-mediated inhibitory effect. PD98059, a specific MAP kinase inhibitor, prevented RON-mediated anti-apoptotic activities. PD98059 also prevented the inhibitory effect of RON on TGF-1-induced cleavage of caspase-3 and BAD. By protecting cells from apoptotic death, activated RON collaborates with TGF-1 in the induction of cell morphological changes with decreased E-cadherin expression and increased migration and morphogenesis. Thus, RON expression and activation modulate phenotypes of gastrointestinal epithelial cells in response to TGF-1 with reduced sensitivity to apoptosis and increased migration. These activities might represent a mechanism by which RON activation increases tumorigenic activities and facilitates the progression of transformed epithelial cells towards malignancy. [ABSTRACT FROM AUTHOR]

Normal adhering cells undergo apoptosis shortly after loss of adhesion to substratum, a phenomenon known as "anoikis." In-vitro-transformed cells and cancer-derived cells are able to survive and grow in the absence of anchorage to the extracellular matrix (ECM) and their neighboring cells. This represents one of the most important oncogenic properties of cancer cells. Integrin-ECM-mediated function is essential for survival and growth of normal adhering cells, while cancer cells are able to abrogate this requirement. This article will review and summarize the recent findings from our laboratory about the molecular signaling pathways important for the regulation of anchorage-independent survival and the growth of transformed fibroblasts and epithelial cells. Our study has shown that integrin-ECM-mediated signaling and cytoskeletal architecture play an essential role in effective recognition of the substrates by activated protein-tyrosine kinases (PTK) and their subsequent signaling functions. Among the various oncogenic PTK-activated pathways, phosphatidylinositol 3-kinase {PI3K)/Akt signaling is the most critical for anchorage-independent survival and growth. The activation of signal transducer and activator of transcription-3 (Slat3) and its function overlap partially with that of the PT3K/Akt in promoting anchorage-independent growth. Among the Rho family guanosine triphosphatases (GTPase), Cdc42, and to some extent Rac1. also appear to be important for promoting anchorage-independent growth. [ABSTRACT FROM AUTHOR]

Atorvastatin has been shown to reduce early brain edema and neuronal death after subarachnoid hemorrhage, but its mechanism is not clear. In this study, rat models of subarachnoid hemorrhage were established by autologous blood injection in the cisterna magna. Rat models were intragastrically administered 20 mg/kg atorvastatin 24 hours before subarachnoid hemorrhage, 12 and 36 hours after subarachnoid hemorrhage. Compared with the controls, atorvastatin treatment demonstrated that at 72 hours after subarachnoid hemorrhage, neurological function had clearly improved; brain edema was remarkably relieved; cell apoptosis was markedly reduced in the cerebral cortex of rats; the number of autophagy-related protein Beclin-1-positive cells and the expression levels of Beclin-1 and LC3 were increased compared with subarachnoid hemorrhage only. The ultrastructural damage of neurons in the temporal lobe was also noticeably alleviated. The similarities between the effects of atorvastatin and rapamycin were seen in all the measured outcomes of subarachnoid hemorrhage. However, these were contrary to the results of 3-methyladenine injection, which inhibits the signaling pathway of autophagy. These findings indicate that atorvastatin plays an early neuroprotective role in subarachnoid hemorrhage by activating autophagy. The experimental protocol was approved by the Animal Ethics Committee of Anhui Medical University, China (904 Hospital of Joint Logistic Support Force of PLA; approval No. YXLL-2017-09) on February 22, 2017.

RACK1 is a 7-WD motif-containing protein with numerous downstream effectors regulating various cellular functions. Using a yeast two-hybrid screen, we identified dynein light chain 1 as a novel interacting partner of RACK1. Additionally, we demonstrated that RACK1 formed a complex with DLC1 and Bim, specifically BimEL, in the presence of apoptotic agents. Upon paclitaxel treatment, RACK1, DLC1, and CIS mediated the degradation of BimEL through the ElonginB/C-Cullin2-CIS ubiquitin-protein isopeptide ligase complex. We further showed that RACK1 conferred paclitaxel resistance to breast cancer cells in vitro and in vivo. Finally, we observed an inverse correlation between CIS and BimEL levels in both ovarian and breast cancer cell lines and specimens. Our study suggests a role of RACK 1 in protecting cancer cells from apoptosis by regulating the degradation of BimEL, which together with CIS could play an important role of drug resistance in chemotherapy. [ABSTRACT FROM AUTHOR]