Quercetin inhibits invasion and angiogenesis of esophageal cancer cells.

BACKGROUND: Esophageal carcinoma has poor prognosis and novel therapies for esophageal carcinoma are urgently needed. Quercetin is a natural flavonoid compound that can be found in many foods. In this study, we investigated the effects of quercetin on invasion and angiogenesis of esophageal cancer cells. METHODS: Human esophageal cancer cell line Eca109 was treated with 5 µg/mL or 10 µg/mL of quercetin. Colony formation assay was performed. Cell migration and invasion were evaluated by wound healing and transwell assays, respectively. Human umbilical vein/vascular endothelium cells (CLR-1730) were treated with Eca109 conditioned medium, and the effects of quercetin on CLR-1730 were evaluated by wound healing and tube formation assays. Protein levels of VEGF-A, MMP9, and MMP2 were determined by Western blotting. RESULTS: The ability of colony forming in Eca109 was reduced with the administration of 10 µg/mL quercetin, but there was no difference between the 5 µg/mL quercetin group and control. The migration distance and the number of invasive cells were significantly reduced in the 10 µg/mL quercetin group. At the lower level of quercetin at 5 µg/mL, only the invasion of cells was significantly inhibited. In endothelial cells treated with Eca109 conditioned medium, cell migration and tube forming ability were suppressed. The decreased protein levels of VEGF-A, MMP9, and MMP2 were observed at the 10 µg/mL quercetin group. CONCLUSION: Quercetin suppressed the invasion and angiogenesis of esophageal cancer cells, and the effects were associated with the decreased expression of VEGF-A, MMP2, and MMP9.

Metabolic syndrome prevalence in patients with obstructive sleep apnea syndrome and chronic obstructive pulmonary disease: Relationship with systemic inflammation.

OBJECTIVES: Metabolic syndrome (MetS) is frequent in both chronic obstructive pulmonary disease (COPD) and Obstructive sleep apnea (OSA). The aim of this study was to assess the frequency of MetS and the status of systemic inflammation in overlap syndrome. METHODS: A total of 151 consecutive COPD patients were recruited in this cross-sectional study. Spirometry and polysomnography were done in all patients. The MetS was defined according to the criteria of the International Diabetes Federation. Anthropometry, metabolic parameters and inflammatory biomarkers: IL-6, TNF-α, leptin, resistin and adiponectin were recorded. RESULTS: OSA was present in 19.2% COPD patients. Subjects with overlap syndrome had higher neck and waist circumference compared to those with COPD alone. Significant differences in levels of blood pressure, lipid metabolic and glucose metabolic were found between two groups with overlap and COPD, as well as inflammatory biomarkers. Prevalence of MetS was increased in overlap group. Multivariate logistic regression showed that BMI, systolic BP when fall asleep and recumbent angiotens levels as significant independent predictors of the presence of Mets in overlap syndrome. CONCLUSION: This study shows that MetS is frequent in patients with overlap. Overlap syndrome indicates a higher cardiometabolic risk and higher levels of systemic inflammatory.

Effect of silencing S-phase kinase-associated protein 2 on chemosensitivity to temozolomide of human glioma cells U251.

OBJECTIVE: To examine the effect of silencing SKP2 on chemosensitivity of human glioma cells U251 to temozolomide (TMZ). METHODS: Adenoviruses harbouring shRNA targeting SKP2 (i.e. Ad-shSKP2) and non-targeting scrambled shRNA (i.e. Ad-shNC) were used to infect U251 cells. The transduced cells were then treated with TMZ. Cell viability after treatment was assayed using CCK8; while cell cycle and apoptosis were examined using flow cytometry. To study the effect of silencing SKP2 on autophagy in U251, we co-transduced the cells with Ad-mRFP-LC3 and Ad-shSKP2/Ad-shNC. The expression of autophagy marker LC3 after TMZ treatment was studied using microscopy and Western blotting assays. RESULTS: The cytotoxicity of TMZ (i.e. 20-100 µM) was more significantly seen in Ad-shSKP2-transduced U251 cells than in the Ad-shNC-transduced U251 cells. The IC50 values in shSKP2-U251 were significantly lower than those of the shNC-U251 (P < 0.05). Both TMZ and Ad-shSKP2 alone increased apoptosis and promoted expression of LC3 in U251. Combined treatment of Ad-shSKP2 and TMZ further elevated apoptosis and LC3 expression. CONCLUSION: Silencing SKP2 in U251 cells increased chemosensitivity to TMZ that was accompanied with enhanced apoptosis and autophagy. Targeting SKP2 may be a potential approach to potentiate TMZ treatment in patients with glioma.

Low concentration of quercetin antagonizes the invasion and angiogenesis of human glioblastoma U251 cells.

Glioblastoma is the most aggressive type of brain tumor with a very poor prognosis. Therefore, it is always of great importance to explore and develop new potential treatment for glioblastoma. Quercetin, a flavonoid present in a variety of human foods, has been shown to inhibit various tumor cell proliferation. In this study, we found that treating human glioblastoma U251 cells with 10 µg/mL quercetin for 24 hours, a concentration that was far below the IC50 (113.65 µg/mL) and at which quercetin failed to inhibit cell proliferation, inhibited cell migration (30%) and cell invasion as examined by wound scratch assay and transwell assay, respectively. We further showed that 10 µg/mL quercetin inhibited cell migration and tube formation of human umbilical vein endothelial cells induced by the conditioned medium derived from U251 cell culture. The inhibitory effect of quercetin on migration and angiogenesis is possibly mediated through the downregulation of protein levels of VEGFA, MMP9, and MMP2 as detected by Western blot. Our findings demonstrated that low concentration of quercetin antagonized glioblastoma cell invasion and angiogenesis in vitro.

Effects of quercetin on proliferation and migration of human glioblastoma U251 cells.

Quercetin is a flavonoid that has been shown to have anti-oxidation, anti-inflammation, anti-allergic, anti-viral, and anti-cancer activities. Here, we examined the effects of quercetin on cell viability, cell cycle progression, and migration in U251 cells, a human glioblastoma cell line. We found that quercetin inhibited cell proliferation after treating cells for 24 (IC50 of 113.65µg/ml) or 48h (IC50 of 48.61µg/ml). Quercetin treatment also induced apoptosis via deregulating the expression of apoptotic genes, including Bax and Bcl-2, and arrested cell cycle at G2/M phases. We further found that quercetin impaired cell migration and invasion via downregulating the expression of matrix metallopeptidases MMP9 and MMP2. Our results provide evidences that quercetin has inhibitory effects on glioblastoma cell proliferation and invasion, and suggest a potential clinical application for glioblastoma.

Conventional transbronchial needle aspiration technique guided by rapid on-site evaluation / 天津医药

Transbronchial needle aspiration (TBNA), which has excellent sensitivity and specificity, is one of the key techniques of diagnostic interventional pulmonology. The conventional TBNA (C-TBNA) is routinely operated with ordinary bronchoscopy under local anesthesia. The efficacy of C-TBNA can be improved when rapid on-site evaluation (ROSE) is used during operating procedure. This paper describes technical essentials of ROSE-based C-TBNA.

Ebb-and-flow of macroautophagy and chaperone-mediated autophagy in Raji cells induced by starvation and arsenic trioxide.

Autophagy is crucial in the maintenance of homeostasis and regenerated energy of mammalian cells. Macroautophagy and chaperone-mediated autophagy(CMA) are the two best-identified pathways. Recent research has found that in normal cells, decline of macroautophagy is appropriately parallel with activation of CMA. However, whether it is also true in cancer cells has been poorly studied. Here we focused on cross-talk and conversion between macroautophagy and CMA in cultured Burkitt lymphoma Raji cells when facing serum deprivation and exposure to a toxic compound, arsenic trioxide. The results showed that both macroautophagy and CMA were activated sequentially instead of simultaneously in starvation-induced Raji cells, and macroautophagy was quickly activated and peaked during the first hours of nutrition deprivation, and then gradually decreased to near baseline. With nutrient deprivation persisted, CMA progressively increased along with the decline of macroautophagy. On the other hand, in arsenic trioxide-treated Raji cells, macroautophagy activity was also significantly increased, but CMA activity was not rapidly enhanced until macroautophagy was inhibited by 3-methyladenine, an inhibitor. Together, we conclude that cancer cells exhibit differential responses to diverse stressor-induced damage by autophagy. The sequential switch of the first-aider macroautophagy to the homeostasis-stabilizer CMA, whether active or passive, might be conducive to the adaption of cancer cells to miscellaneous intracellular or extracellular stressors. These findings must be helpful to understand the characteristics, compensatory mechanisms and answer modes of different autophagic pathways in cancer cells, which might be very important and promising to the development of potential targeting interventions for cancer therapies via regulation of autophagic pathways.

Arsenic trioxide induces autophagy and antitumor effects in Burkitt's lymphoma Raji cells.

Although it is generally acknowledged that auto-phagy plays an important role in tumorigenesis and therapy, studies of autophagy in different cell types and under different conditions have led to conflicting theories regarding the influence of autophagy on cell death. In the present study, we explored the role of autophagy and its underlying mechanism in the inhibitory effects of arsenic trioxide (As2O3) on Burkitt's lymphoma Raji cells. The results showed that As2O3 significantly inhibited the proliferation of Raji cells in a dose- and time-dependent manner, induced G2/M phase cell cycle arrest and apoptosis. Moreover, As2O3 also promoted the formation of autophagic vacuoles, as well as increased the degradation of autophagy substrate P62 protein, which was accompanied by an upregulation of Beclin-1 gene and a downregulation of Bcl-2 gene expression. 3-Methyladenine, an autophagy inhibitor, not only increased cell viability through inhibiting autophagic cell death and apoptosis, but also reversed the upregulation of Beclin-1 gene and the downregulation of Bcl-2 gene in the Raji cells induced by As2O3. These results may lead to a better understanding of the action of As2O3 and may provide evidence that autophagy plays an important role in the regulation of cell death. Therefore, regulation of autophagic activity may be a promising therapy for patients with Burkitt's lymphoma.

Insulin resistance reduces sensitivity to Cis-platinum and promotes adhesion, migration and invasion in HepG2 cells.

The liver is normally the major site of glucose metabolism in intact organisms and the most important target organ for the action of insulin. It has been widely accepted that insulin resistance (IR) is closely associated with postoperative recurrence of hepatocellular carcinoma (HCC). However, the relationship between IR and drug resistance in liver cancer cells is unclear. In the present study, IR was induced in HepG2 cells via incubation with a high concentration of insulin. Once the insulin-resistant cell line was established, the instability of HepG2/ IR cells was further tested via incubation in insulin-free medium for another 72h. Afterwards, the biological effects of insulin resistance on adhesion, migration, invasion and sensitivity to cis-platinum (DDP) of cells were determined. The results indicated that glucose consumption was reduced in insulin-resistant cells. In addition, the expression of the insulin receptor and glucose transportor-2 was downregulated. Furthermore, HepG2/IR cells displayed markedly enhanced adhesion, migration, and invasion. Most importantly, these cells exhibited a lower sensitivity to DDP. By contrast, HepG2/IR cells exhibited decreased adhesion and invasion after treatment with the insulin sensitizer pioglitazone hydrochloride. The results suggest that IR is closely related to drug resistance as well as adhesion, migration, and invasion in HepG2 cells. These findings may help explain the clinical observation of limited efficacy for chemotherapy on a background of IR, which promotes the invasion and migration of cancer cells.

[Comparison of two different chemotherapy regimens for concurrent chemoradiotherapy in stage Ib2 to IVa squamous cell carcinoma of the uterine cervix].

OBJECTIVE: To compare the clinical efficacy and safety of two chemotherapy regimens for concurrent chemoradiotherapy in patients with stage Ib2 to IVa squamous cell carcinoma of the uterine cervix. METHODS: Between November 2007 and November 2011, 146 patients with stage Ib2 to IVa squamous cell carcinoma of the uterine cervix who received concurrent chemoradiotherapy in Peking University Cancer Hospital were analyzed. All cases were divided into two groups according to the different chemotherapy regimens during radiation therapy, the group receiving radiotherapy concomitant with weekly cisplatin or nedaplatin alone (platinum alone group, n = 59), the group receiving radiotherapy concomitant with cisplatin plus fluorouracil or nedaplatin plus tegafur every 3 weeks (combined group, n = 87). There were no statistical difference in the clinical and pathological characteristics between the two groups. RESULTS: Patients were evaluated by pelvic examination and pelvic MRI after chemoradiotherapy for 3 months according to WHO criteria. The response rate were respectively 97% (57/59) and 93% (81/87) in platinum alone group and combined group, in which there was no significant difference (P = 0.249). The five-year overall survival and the five-year progression-free survival of platinum alone group and combined group were respectively 61.2% versus 69.5% (P > 0.05) and 43.3% versus 24.4% (P > 0.05). There were also no statistically significant differences between platinum alone group and combined group in the five-year local recurrence rate and five-year distant metastasis (11.8% versus 9.8%, 29.4% versus 38.7%; all P > 0.05). Acute gastrointestinal toxicities (nausea and vomiting) in combined group were exactly higher than that in the other group [78% (68/87) versus 51% (30/59), P < 0.01]. Moreover, anaemia was slightly more common in combined group [53% (46/87) versus 25% (15/59), P = 0.019]. However, the occurrence rate of the acute or late proctitis and cystitis did not reveal difference between two groups (P > 0.05). CONCLUSIONS: Both concurrent chemoradiotherapy regimens had similar efficacy on cervical cancer patients with stage Ib2 to IVa. But the toxicity was lower in patients with weekly platinum than those with platinum-based combined regimens during radiation therapy.

[The analysis of HLA-A, B and DRB1 allelic polymorphism in Han race population in Lanzhou region of China].

OBJECTIVE: To investigate the HLA-A, B and DRB1 allele polymorphism of the Han race population in Lanzhou area. METHODS: Polymerase chain reaction-sequence specific primer was used to detect HLA-A, B and DRB1 alleles in 200 unrelated healthy Han individuals from Lanzhou region, Northwest China, and the results were compared with those of Han populations in North, South and Northwest China, and Hui, Uigur and Tibetan population in China. RESULTS: Fourteen of alleles were detected and identified for HLA-A; 32 for HLA-B; and 13 for HLA-DRB1. HLA- A*01, A*02,A*11,A*24, A*30, A*31, A*33; HLA- B*13, B*15, B*40, B*44, B*46, B*51, B*58, B*60; HLA- DRB1*04,. DRB1*07, DRB1*08, DRB1*09, DRB1*11, DRB1*12, DRB1*14 and DRB1*15 were the most common alleles. The frequencies of HLA-A, B and DRB1 genes of Lanzhou Han race were close to that of North China Hans and Hui population in Northwest China, and a little different to that of South China Hans. The HLA-DRB1 alleles were significantly different to those of Uigur and Tibetan race population of China. CONCLUSION: The allelic polymorphism of HLA-A,B and DRB1 loci of Han race population in Lanzhou area was between North and South Han race of China, close to Northwest China Hui, and markedly different to Northwest China Uigur and Tibetan race populations.