Tumor-derived extracellular vesicles: how they mediate glioma immunosuppression.

Gliomas, the most common malignant brain tumor, present a grim prognosis despite available treatments such as surgical resection, temozolomide (TMZ) therapy, and radiation therapy. This is due to their aggressive growth, high level of immunosuppression, and the blood-brain barrier (BBB), which obstruct the effective exchange of therapeutic drugs. Gliomas can significantly affect differentiation and function of immune cells by releasing extracellular vesicles (EVs), resulting in a systemic immunosuppressive state and a highly immunosuppressive microenvironment. In the tumor immune microenvironment (TIME), the primary immune cells are regulatory T cells (Tregs), myeloid-derived suppressor cells (MDSCs), and tumor-associated macrophages (TAMs). In particular, glioma-associated TAMs are chiefly composed of monocyte-derived macrophages and brain-resident microglia. These cells partially exhibit characteristics of a pro-tumorigenic, anti-inflammatory M2-type. Glioma-derived EVs can hijack TAMs to differentiate into tumor-supporting phenotypes or directly affect the maturation of peripheral blood monocytes (PBMCs) and promote the activation of MDSCs. In addition, EVs impair the ability of dendritic cells (DCs) to process antigens, subsequently hindering the activation of lymphocytes. EVs also impact the proliferation, differentiation, and activation of lymphocytes. This is primarily evident in the overall reduction of CD4 + helper T cells and CD8 + T cells, coupled with a relative increase in Tregs, which possess immunosuppressive characteristics. This study investigates thoroughly how tumor-derived EVs impair the function of immune cells and enhance immunosuppression in gliomas, shedding light on their potential implications for immunotherapy strategies in glioma treatment.

Recombinant adenoviral vector expressing human wild-type p53, GM-CSF, and B7-1 genes suppresses the growth of glioma in vivo.

Malignant gliomas are the most common of primary brain tumors and have been proven incurable with conventional treatments. Evidence have shown that a recombinant adenoviral vector expressing human wild-type p53, granulocyte-macrophage colony-stimulating factor (GM-CSF), and B7-1 genes (BB-102) may have antitumor effects in vitro. In this study, we investigated the effects of BB-102-based vaccine on glioma in vivo. An animal model using nonobese diabetic/severe combined immunodeficiency (NOD/SCID) mice with human immune system was established. The mice were vaccinated with inactivated U251 glioma cells transduced with BB-102 or adenoviral vector expressing green fluorescence protein (Ad-GFP) as a control and followed by the challenge of live U251 glioma cells. Tumor growth and antitumor responses were measured. Data showed that mice vaccinated with BB-102 had significantly reduced local tumor growth compared to mice with Ad-GFP vaccination or the control group. Histopathological analysis displayed low tumor cell density and significant infiltration of human peripheral blood lymphocytes (HuPBLs) in the tumor tissues of mice transduced with BB-102. Immunohistochemical analysis showed that mutant p53 was not expressed in tumor tissues of mice with BB-102 vaccination, and the expression level of Ki67 was significantly lower in the tumor tissues of the BB-102 group than those in the Ad-GFP group or the control group. Further study demonstrated that mice with BB-102 vaccination had significantly increased total T cell numbers, total T cell proportion, CD4+ T cell proportion, and CD8+ T cell proportion in spleens, as well as higher value of IgG, IgA, and IgE in sera. These data suggest that the recombinant adenoviral vector expressing human wild-type p53, GM-CSF, and B7-1 genes could suppress glioma in NOD/SCID mice model and might be considered as a novel strategy for glioma therapy.

[Application research of polysomnography and lateral cephalometric radiographs in the diagnosis and treatment of sleep-disordered breathing in children].

OBJECTIVE: To explore the application of polysomnography (PSG) and lateral cephalometric radiographs (LCR) in the diagnosis and treatment of sleep-disordered breathing (SDB) in children. METHOD: To select 157 cases of children suffering from SDB, 115 cases with primary snoring (PS) and 42 cases with obstructive sleep apnea hypopnea syndrome (OSAHS). After bilateral tonsillectomy and adenoidectomy, preoperative and postoperative LCR and PSG of measure were observed for statistical analysis. RESULT: Compared the group PS and group OSAHS; the thickness of adenoids was significantly different(P<0. 01). The preoperative oblique diameter of nasopharyngeal airway was significantly different (P<0. 05). There were significant differences on the preoperative and postoperative nasopharyngeal airway oblique diameter and oropharyngeal airway anteroposterior diameter in group PS and group OSAHS (all, P<0. 01). There were significant differences on the preoperative and postoperative AHI and LSaO2 in the group OSAHS (both, P<0. 01). The total effective rate of group PS was 97. 4% (112/115), and the total effective rate of group OSAHS was 97. 6% (41/42). CONCLUSION: PSG and LCR have a very important role in the diagnosis and treatment of SDB in children. Bilateral tonsillectomy and adenoidectomy are the primary means of treatment in children with SDB.

8-hydroxy-2-(di-n-propylamino)tetralin intervenes with neural cell apoptosis following diffuse axonal injury.

Previous studies have reported a neuroprotective effect of 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT) against traumatic brain injury. In accordance with the Marmarou method, rat models of diffuse axonal injury were established. 8-OH-DPAT was intraperitoneally injected into model rats. 8-OH-DPAT treated rats maintained at constant temperature served as normal temperature controls. TUNEL results revealed that neural cell swelling, brain tissue necrosis and cell apoptosis occurred around the injured tissue. Moreover, the number of Bax-, Bcl-2- and caspase-3-positive cells increased at 6 hours after diffuse axonal injury, and peaked at 24 hours. However, brain injury was attenuated, the number of apoptotic cells reduced, Bax and caspase-3 expression decreased, and Bcl-2 expression increased at 6, 12, 24, 72 and 168 hours after diffuse axonal injury in normal temperature control and in 8-OH-DPAT-intervention rats. The difference was most significant at 24 hours. All indices in 8-OH-DPAT-intervention rats were better than those in the constant temperature group. These results suggest that 8-OH-DPAT inhibits Bax and caspase-3 expression, increases Bcl-2 expression, and reduces neural cell apoptosis, resulting in neuroprotection against diffuse axonal injury. This effect is associated with a decrease in brain temperature.

Adenovirus mediated transfer of p53, GM-CSF and B7-1 suppresses growth and enhances immunogenicity of glioma cells.

OBJECTIVES: Malignant gliomas are good targets for gene therapy because they have been proven incurable with conventional treatments. However, malignant gliomas are genetically and physiologically highly heterogeneous, and current gene therapy interventions have been designed to target only a few variations of this kind of disease. Hence, we developed a combined gene therapy approach using a recombinant adenovirus carrying human wild-type p53 (WT-p53), granulocyte-macrophage colony-stimulating factor (GM-CSF) and B7-1 genes (designated BB-102) to combat the disease. METHODS: Human malignant glioma cells U251 and U87 were transduced with BB-102. Expression of WT-p53, GM-CSF and B7-1 genes were determined by Western blot, enzyme linked immunosorbent assay and flow cytometric analysis, respectively. Growth rates were determined by serial cell counts. Apoptosis was detected by flow cytometric analysis. Proliferation of autologous peripheral blood lymphocytes (PBLs) and cytotoxicity against primary glioma cells were assessed by cell proliferation and cytotoxicity assay kits, respectively. RESULTS: By the transduction of BB-102, high expression levels of the three exogenesis genes were detected in glioma cells. Cell growth was inhibited and apoptosis was induced. Significant proliferation of autologous PBLs and specific cytotoxicity against primary glioma cells were also induced by the infection of BB-102 in vitro, with the effect being more evident than that of Ad-p53. CONCLUSION: These results suggest that glioma cell vaccination co-transferred with p53, GM-CSF and B7-1 genes may be a feasible and effective immunotherapeutic approach in glioma treatments.

Expression of p27(kip1), Rb protein and proliferating cell nuclear antigen and its relationship with clinicopathology in human pancreatic cancer.

OBJECTIVE: To investigate the effect of inhibiting factor of cell cycle regulation p27(kip1), retinoblastinoma protein (Rb protein), and proliferating cell nuclear antigen (PCNA) on the genesis and progression of human pancreatic cancer. METHODS: The expression of p27(kip1), Rb protein and PCNA in the tumor tissue and adjacent tissue of 32 patients with pancreatic cancer was detected by SP immunohistochemical technique. RESULTS: The p27(kip1) protein positive-expression rate in the tumor tissue of pancreatic cancer was 56.25%, which was lower than that in the adjacent pancreatic tissue (P<0.05). p27(kip1) protein positive-expression was correlated significantly with tumor cell differentiation and lymph node metastasis (P<0.05). The Rb gene protein positive-expression rate in the tumor tissue was 50%, which was also lower than that in the adjacent pancreatic tissue (P<0.05). The PCNA positive-expression rate was 71.87%, which was higher than that in the adjacent pancreatic tissue (P<0.05). PCNA positive-expression was also correlated significantly with tumor cell differentiation and lymph node metastasis (P<0.05). CONCLUSION: The decreased expression of p27(kip1), Rb protein and over-expression of PCNA may play an important role in the genesis and progression of pancreatic cancer.

Expression of P57(kip2) and cyslinE proteins in human pancreatic cancer.

OBJECTIVE: To investigate the effects of p57(kip2) and cyclinE proteins on the genesis and progression of human pancreatic cancer. METHODS: The expression of p57(kip2) and cyclinE proteins in tumor tissues and adjacent tissues of pancreatic cancer in 32 patients was detected by SP immunohistochemical technique. RESULTS: The p57(kip2) protein positive-expression rate in tumor tissues of pancreatic cancer was 46.9%, which was lower than that in adjacent pancreatic tissue (P < 0.05). The p57(kip2) protein positive-expression correlated significantly with tumor cell differentiation (P < 0.05) and did not correlate significantly with lymph node metastasis (P > 0.05). The cyclinE positive-expression rate in tumor tissues was 68.8%, which was higher than that in adjacent pancreatic tissues (P < 0.05). The cyclinE positive-expression also correlated significantly with tumor cell differentiation and lymph node metastasis (P < 0.05). The cyclinE protein positive-expression rate in the tumor tissues of the p57(kip2) protein positive-expression group was lower than that in the p57(kip2) protein negative-expression group, and there were no significant correlation between the two groups (r = -0.112, P > 0.05). CONCLUSION: Decreased expression of the p57(kip2) protein and/or over-expression of the cyclinE protein may play an important role in the genesis and progression of human pancreatic cancer.

[Relationship between expression of p57(kip2), cyclin E protein, PCNA, and clinicopathological factors in human pancreatic cancer].

BACKGROUND & OBJECTIVE: The abnormality of mammalian cell cycle regulation is an important cause of cell over-proliferation and oncogenesis. There were few reports about the relationship between p57(kip2) protein as negative factor of cell cycle regulation and pancreatic cancer. This article aims to investigate the effects of p57(kip2), cyclin E and proliferating cell nuclear antigen (PCNA) protein on the occurrence and progression of pancreatic cancer. METHODS: Expression of p57(kip2), cyclin E, and PCNA in tumor tissue and adjacent tissue from 32 patients with pancreatic cancer were detected using SP immunohistochemical technique. RESULTS: The positive-expression rate of p57(kip2) protein in tumor tissue of pancreatic cancer was 46.9%, which was lower than that in adjacent pancreatic tissue (75.0%) (Chi(2)=5.317, P< 0.05); p57(kip2) protein positive-expression was remarkably correlated with tumor cell differentiation (P< 0.05), but was not correlated with lymph node metastasis (P >0.05). The positive-expression rate of cyclin E in tumor tissues was 68.8%, which was higher than that in adjacent pancreatic tissue (43.8%) (Chi(2)=4.063,P< 0.05); Cyclin E positive-expression was remarkably correlated with tumor cell differentiation and lymph node metastasis (P< 0.05). The positive-expression rate of PCNA protein in tumor tissues was 71.9%, which was higher than that in adjacent pancreatic tissue (43.8%) (Chi(2)=5.189,P< 0.05); PCNA positive- expression was remarkably correlated with tumor cell differentiation and lymph node metastasis(P< 0.05). CONCLUSION: The decreased expression of p57(kip2) protein and over-expression of cyclin E and PCNA proteins may significantly related to genesis and progress of pancreatic cancer.

Expression of p57kip2, Rb protein and PCNA and their relationships with clinicopathology in human pancreatic cancer.

AIM: To investigate the effects of inhibiting factor of cell cycle regulation p57(kip2), retinoblastinoma protein (Rb protein) and proliferating cell nuclear antigen (PCNA) in the genesis and progression of human pancreatic cancer. METHODS: The expression of p57(kip2), Rb protein and PCNA in tumor tissues and adjacent tissues of 32 patients with pancreatic cancer was detected with SP immunohistochemical technique. RESULTS: p57(kip2) protein positive-expression rate in tumor tissues of pancreatic cancer was 46.9 %, which was lower than that in adjacent pancreatic tissues (75.0 %) (chi(2)=5.317, P<0.05), p57(kip2) protein positive-expression correlated significantly with tumor cell differentiation (well-differentiation versus moderate or low-differentiation, P<0.05) but did not correlate significantly with lymph node metastasis (lymph node metastasis versus non-lymph node metastasis, P>0.05); Rb gene protein positive-expression rate in tumor tissues was 50.0 %, which was also lower than that in adjacent pancreatic tissues (78.1 %) (chi(2)=5.497, P<0.05); PCNA positive-expression rate was 71.9 %, being higher than that in adjacent pancreatic tissues (43.8 %) (chi(2)=5.189, P<0.05), PCNA positive-expression also correlated significantly with tumor cell differentiation and lymph node metastasis (well-differentiation versus moderate or low- differentiation, lymph node metastasis versus non-lymph node metastasis, P<0.05). Rb protein positive-expression rate in the tumor tissues of p57(kip2) protein positive-expression group was 53.3 %; and Rb protein positive-expression rate in the tumor tissues of p57(kip2) protein negative-expression group was 47.1 %. There was no significant relationship between the two groups (r=0.16507, P>0.05). CONCLUSION: The decreased expression of p57(kip2), Rb protein or over-expression of PCNA protein might contribute to the genesis or progression of pancreatic cancer, p57(kip2), Rb protein and PCNA may play an important role in genesis and progression of pancreatic cancer.

Clinical significance of TGF- beta1 and beta-glucuronidase synchronous detection in human pancreatic cancer.

OBJECTIVE: To investigate the relation of transfer growth factor (TGF-beta1) and beta-glucuronidase (beta-GCD) on the occurrence and progress of pancreatic cancer. METHODS: The expression of TGF-beta1 and beta-GCD in the pancreatic cancer tissue and normal pancreatic tissue was determined synchronously using ABC method of immunohistochemistry. RESULTS: The percentage of TGF-beta1 positive cells was significantly higher in pancreatic cancer tissue (43.8%+/-5.2%) than in adjacent pancreatic tissue (28.7%+/-3.6%, P<0.01). The worse the cancer cells differentiated and lymph nodes metastasis, the more over-expression of TGF-beta1. The percentage of beta-GCD positive cells was also significantly higher in the pancreatic cancer tissue (62.5%+/-4.1%) than in the adjacent pancreatic tissue (33.5%+/-2.8%, P<0.01). The degree of over-expression of beta-GCD was related to the degree of cancer cells differentiation, but not to the lymph nodes metastasis. The expression of TGF-beta1 was significantly correlated with the expression of beta-GCD in pancreatic cancer tissue. CONCLUSIONS: The genesis of pancreatic cancer results from multi-factor, multi-step and multi-gene variation. The synchronous detection of TGF-beta1 and beta-GCD helps to determine the malignant degree of tumors and the prognosis of patients with such disease.