A collagen-based multicellular tumor spheroid model for evaluation of the efficiency of nanoparticle drug delivery.

Targeted drug delivery systems, especially those that use nanoparticles, have been the focus of research into cancer therapy during the last decade, to improve the bioavailability and delivery of anticancer drugs to specific tumor sites, thereby reducing the toxicity and side effects to normal tissues. However, the positive antitumor effects of these nanocarriers observed in conventional monolayer cultures frequently fail in vivo, due to the lack of physical and biological barriers resembling those seen in the actual body. Therefore, the collagen-based 3-D multicellular culture system, to screen new nanocarriers for drug delivery and to obtain more adequate and better prediction of therapeutic outcomes in preclinical experiments, was developed. This 3-D culture model was successfully established using optimized density of cells. Our result showed that 3-D cell colonies were successfully developed from 95-D, U87 and HCT116 cell lines respectively, after a seven-day culture in the collagen matrix. The coumarin-conjugated nanoparticles were able to penetrate the matrix gel to reach the tumor cells. The model is supposedly more accurate in reflecting/predicting the dynamics and therapeutic outcomes of candidates for drug transport in vivo, and/or investigation of tumor biology, thus speeding up the pace of discovery of novel drug delivery systems for cancer therapy.

The association study on renalase polymorphism and hypertension: a meta-analysis.

Hypertension is considered a multi-factorial disease since its development is affected by both genetic and environmental factors. Intensive efforts have been focused on identifying gene(s) related to hypertension. Renalase is a recently discovered protein that expressed in kidney, heart, liver, and brain that metabolizes catecholamines, regulation of blood pressure in humans and animals. A common missense polymorphism in the flavin-adenine dinucleotide-binding domain of human renalase (Glu37Asp) has recently been described. But the reported results are not always consistent. In this meta-analysis, we examined the association between (Glu37Asp) polymorphism (rs2296545) in renalase gene and risk of hypertension. Through a systematic literature search for publications between 2007 and 2014, we summarized the data from 4 studies on polymorphism (rs2296545) in renalase gene and risk of hypertension. We did not find any association of rs2296545 with risk of hypertension in dominant model (OR=0.64; 95% CI: 0.41-1.00), recessive model (OR=1.29, 95% CI: 0.95-1.75), co-dominant model (OR=1.38, 95% CI: 0.92-2.08), and allelic model (OR=1.19; 95% CI: 0.96-1.47). The results of the present study indicated that the renalase genetic polymorphism was not associated with risk of hypertension.

An investigation of antitumor efficiency of novel sustained and targeted 5-fluorouracil nanoparticles.

Traditional chemotherapeutic drugs remain the major treatment for advanced colorectal cancer. However, due to the lack of tumor specificity these drug also destroy healthy tissue and organs, which has been the main reason for treatment failure and mortality. Folate-based drug delivery systems for improving nanoparticle endocytosis have been used to address these problems. Here, folic acid (FA) conjugated mPEG-b-P(CABCL-co-ACL) diblock copolymers were synthesized and characterized by TEM and NMR. Drug loaded nanoparticles were prepared using dialysis method and was obtained with a mean diameter of 45.2 nm with sustained in vitro release profile. In vitro cytotoxicity assay indicated that the cytotoxicity of folate modified nanoparticles were significantly increased compared to free drug and non-folate nanoparticles. In addition, results of hemolytic and histopathologic study suggested that the non-loaded nanoparticle (NL/NP) was non-toxic and biocompatible at the testing concentration. Moreover, in vivo results showed that FA/5-FU/NP effectively inhibited growth of HCT-8 cell-based xenograft tumors in BALB/c mice and revealed stronger antitumor efficacy than other treated groups. Thus, both in vitro and in vivo results exhibited that the folate conjugated mPEG-b-P(CABCL-co-ACL) copolymers have great potential to be used as sustainable and specific colon cancer targeting delivery system for anticancer agents.

Overcoming multidrug resistance in 2D and 3D culture models by controlled drug chitosan-graft poly(caprolactone)-based nanoparticles.

The principal limitations of chemotherapy are dose-limiting systemic toxicity and the development of multidrug-resistant phenotypes. The aim of this study was to investigate the efficiency of a new sustained drug delivery system based on chitosan and ε-caprolactone to overcome multidrug resistance in monolayer and drug resistance associated with the three-dimensional (3D) tumor microenvironment in our established 3D models. The 5-fluorouracil (5-FU)-loaded nanoparticles (NPs) were characterized by transmission electron microscope and dynamic light scattering, and its released property was determined at different pH values. 5-FU/NPs exhibited well-sustained release properties and markedly enhanced the cytotoxicity of 5-FU against HCT116/L-OHP or HCT8/VCR MDR cells in two-dimensional (2D) and its parental cells in 3D collagen gel culture with twofold to threefold decrease in the IC50 values, as demonstrated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Hoechst/propidium iodide staining and flow cytometry analysis. Furthermore, the possible mechanism was explored by high-performance liquid chromatography and rhodamine 123 accumulation experiment. Overall, the results demonstrated that 5-FU/NPs increase intracellular concentration of 5-FU and enhance its anticancer efficiency by inducing apoptosis. It was suggested that this novel NPs are a promising carrier to decrease toxic of 5-FU and has the potential to reverse the forms of both intrinsic and acquired drug resistance in 2D and 3D cultures.

[The effect of drainage in cavities on preventing from grade B and C of the pancreatic fistula after pancreaticoduodenectomy].

OBJECTIVE: To explore the effect of drainage in cavities on preventing from grade B and C of the pancreatic fistula after pancreaticoduodenectomy (PD). METHODS: From June 2008 to June 2010, the medical team had performed the operations of digestive tract reconstruction by the same way in 68 cases with PD. There were 43 male and 25 female patients, with a mean age of (64 ± 3) years. The patients were simply randomly divided into drainage in cavities group (DC, n = 32) and conventional drainage group (CD, n = 36) according to the different drainage way. The methods of drainage in cavities were composed of three aspects which include drainage in main pancreatic duct, drainage around cholecystojejunostomy anastomosis and peripancreatic drainage. The clinical parameters of the two groups were collected. The characteristics of the drainage juice which include color, volume and amylase value in the two groups were compared. The incidence and severity grading of pancreatic fistula between the two groups were evaluated. RESULTS: The average of amylase value and the peripancreatic drainage flow were (1401 ± 8) U/L and (49 ± 5) ml in the DC group. Their average in the CD group were (2160 ± 13) U/L and (76 ± 4) ml. There was significant statistical difference in the peripancreatic drainage flow between the two groups (t = 2.597, P = 0.031). The amylase values of the drainage juice between the two groups were of no statistical difference (P > 0.05). According to the definition of pancreatic fistula by an international study group, the incidence of pancreatic fistula in the DC group was 25.0% (8/32) and the CD group 30.5% (11/36) (P > 0.05). The proportion of grades B and C of pancreatic fistula in the DC group had statistical difference compared with one of the CD group (χ(2) = 4.797, P = 0.029). CONCLUSION: Drainage in cavities could significantly decrease and the occurring ratio of grade B and C of pancreatic fistula after PD.

Optimal treatment opportunity for mTHPC-mediated photodynamic therapy of liver cancer.

Photodynamic therapy (PDT) has been clinically used for liver cancer. The pharmacokinetics of a photosensitizer needs to be monitored so that PDT can be performed at the most favorable time and with the proper dose to increase the cure rate. As mTHPC is a fluorescent compound, we investigate its pharmacokinetics, distribution, and elimination in the rat orthotropic liver cancer model in order to confirm an optimal treatment opportunity of liver cancer PDT. After intravenous administration at a single dose of 300 µg/kg, mTHPC was extracted from tissue homogenates or plasma. Then, mTHPC concentrations were assessed by fluorescence spectroscopy and the data were processed with PK-GRAPH pharmacokinetic procedure. The plasma concentration-time profile of mTHPC showed a short distribution half-life (T½α = 0.082 h) and a relatively longer elimination half-life (T½ß = 28.23 h), which quite fitted with a two-compartment model. The results of mTHPC tissue distributions showed that the highest drug accumulation was in tumor tissue, and successively decreased in liver, heart, spleen, muscle, and skin tissues. The drug distribution ratio of tumor to normal tissue reached the peak at 24 h after mTHPC administration. mTHPC was eliminated at a suitable rate in rat orthotropic liver cancer model, and there was no long-term accumulation of mTHPC in rat tissues. For PDT of orthotropic liver cancer, 24 h after mTHPC intravenous injection may be the optimal treatment time point, which might provide higher clinical efficacy and reduce side effects.

[Value of low-dose spiral computed tomography in lung cancer screening].

OBJECTIVE: To explore the application value of low-dose spiral computed tomography (LDCT) in lung cancer screening. METHODS: A total of 2251 asymptomatic subjects undergoing chest LDCT scan at Center of Physical Examination, Affiliated Zhongshan Hospital, Fudan University between June 2011 and December 2012 were prospectively enrolled. The incidence rates of lung nodule and lung cancer were analyzed to compare the value of LDCT screening in subjects with smoking-related high, medium and low risks of lung cancer. The value of serum tumor biomarker in the reduction of false positive of LDCT was also discussed. RESULTS: Among all subjects, 9.9% (222/2251) displayed at least 1 non-calcified nodule with a diameter ≥ 4 mm. Two subjects were diagnosed with lung cancer and 1 of them received surgical resection. Other subjects with lung nodules were followed. There was no statistical difference in the incidence rates of lung nodule between the high, medium and low-risk groups of lung cancer associated with smoking (8.8%, 9.5% and 10.1%, P = 0.864). The incidence rates of lung nodule in subjects ≥ 55 years old were higher than that of those <55 years old (12.7% vs 9.1%, P = 0.034). Female gender had a high risk of ground glass opacity (GGO) or ground glass nodule (GGN) (P = 0.015). The independent or combined increase of serum tumor biomarkers of carcinoembryonic antigen (CEA), neuron specific enolase (NSE), cytokeratin fragment 21-1 (Cyfra211) and squamous cell carcinoma antigen (SCC) might not predicate the incidence of lung nodule. CONCLUSION: LDCT screening is highly valuable in lung cancer screening.

Comparison between air and carbon dioxide insufflation in the endoscopic submucosal excavation of gastrointestinal stromal tumors.

AIM: To evaluate the safety and efficacy of CO(2) insufflation compared with air insufflation in the endoscopic submucosal excavation (ESE) of gastrointestinal stromal tumors. METHODS: Sixty patients were randomized to undergo endoscopic submucosal excavation, with the CO(2) group (n = 30) and the air group (n = 30) undergoing CO(2) insufflation and air insufflation in the ESE, respectively. The end-tidal CO(2) level (pETCO(2)) was observed at 4 time points: at the beginning of ESE, at total removal of the tumors, at completed wound management, and 10 min after ESE. Additionally, the patients' experience of pain at 1, 3, 6 and 24 h after the examination was registered using a visual analog scale (VAS). RESULTS: Both the CO(2) group and air group were similar in mean age, sex, body mass index (all P > 0.05). There were no significant differences in PetCO(2) values before and after the procedure (P > 0.05). However, the pain scores after the ESE at different time points in the CO(2) group decreased significantly compared with the air group (1 h: 21.2 ± 3.4 vs 61.5 ± 1.7; 3 h: 8.5 ± 0.7 vs 42.9 ± 1.3; 6 h: 4.4 ± 1.6 vs 27.6 ± 1.2; 24 h: 2.3 ± 0.4 vs 21.4 ± 0.7, P < 0.05). Meanwhile, the percentage of VAS scores of 0 in the CO(2) group after 1, 3, 6 and 24 h was significantly higher than that in the air group (60.7 ± 1.4 vs 18.9 ± 1.5, 81.5 ± 2.3 vs 20.6 ± 1.2, 89.2 ± 0.7 vs 36.8 ± 0.9, 91.3 ± 0.8 vs 63.8 ± 1.3, respectively, P < 0.05). Moreover, the condition of the CO(2) group was better than that of the air group with respect to anal exsufflation. CONCLUSION: Insufflation of CO(2) in the ESE of gastrointestinal stromal tumors will not cause CO(2) retention and it may significantly reduce the level of pain, thus it is safe and effective.

Entering the duodenal diverticulum: a method for cannulation of the intradiverticular papilla.

Successful cannulation of the common bile duct may be difficult in patients in whom the papilla is located entirely within a diverticulum. In this study, we report successful biliary cannulation in three patients following intubation of the distal tip of the duodenoscope into the duodenal diverticulum and locating the major papilla. No complications occurred during the operation or during the postoperative period. This method didn't need second incubation an endoscope and might lower the burden of patients. So this skill is useful to deal with the papilla hidden inside the large diverticulum because of its safety and convenience.

Evaluation of two modified ECF regimens in the treatment of advanced gallbladder cancer.

Gallbladder cancer is a rare disease and it is associated with a poor clinical outcome and survival. A standard therapy for it has not been established yet. The aim of this study is to evaluate efficacy and safety of two modified ECF regimens in advanced gallbladder cancer patients. Clinical data of 38 patients with advanced gallbladder cancer treated with modified ECF regimen were reviewed retrospectively. Of them, 21 patients received an epirubicin, cisplatin, and 5-FU/LV combination therapy. Seventeen patients received a chemotherapy of epirubicin, cisplatin, and capecitabine. Partial response was achieved in fourteen (36.84%) patients with a median duration of 5 months (range, 3-13 months), while stable disease was achieved in eight patients (21.05%). The median time to progression was 4.0 months (95% CI, 3.62-4.58 months). And the median overall survival was 9.8 months (95% CI, 7.26-12.34 months). Responders demonstrated better survival than non-responders (median survival time: 16 vs. 6.9 months, P = 0.008). The median survival time for epirubicin-, cisplatin- and capecitabine-treated patients was 9.2 versus 8.9 months for epirubicin-, cisplatin- and 5-FU/LV-treated patients. There was no statistical difference between both treatment groups in terms of survival time (P = 0.769). Regimen-related toxicity resulted in at least one treatment delay or dosage reduction in 63.2 and 34.2% patients, respectively. There were no chemotherapy-related deaths during the study. Modified ECF regimen with epirubicin, cisplatin and 5-FU/LV or substituting capecitabine for 5-FU/LV is still a potentially effective therapeutic chemotherapy for patients with advanced gallbladder cancer, and toxicity was manageable. There was no remarkable difference in efficacy between the two regimens.

[Effects of lipid-modulation and antiplatelet treatment on the endothelial lipase expression].

OBJECTIVE: To investigate the effects of lipid-modulation and antiplatelet treatment on the expression of endothelial lipase (EL) of patients with coronary artery disease (CAD), and investigate the role of EL in the development of CAD. METHODS: One hundred and fifty-seven cases were divided into three groups according to clinical manifestations and the results of coronary artery angiography: control group (n=41) with more than one risk factors of CAD and the vessel lesions was <30%; stable angina pectoris (SAP) group (n=55); acute coronary syndrome (ACS) group (n=61). The EL positive cell rate was measured 2 weeks after cessation of lipid-modulation and aspirin treatment, and 6 months after treatment with simvastatin and/or aspirin. The drug was ceased for the complications or not tolerance for the treatment. RESULTS: Except the patients in control group with aspirin treatment, the EL positive cell rate was significantly decreased among other groups [control group with simvastatin: (3.93±0.87)% vs. (5.28±1.05)%, SAP group: (8.16±2.11)% vs. (15.12±2.53)%, ACS group: (13.93±3.22)% vs. (38.44±4.36)%; SAP group with aspirin: (10.57±4.07)% vs. (14.66±2.29)%, ACS group: (18.28±5.14)% vs. (40.27±3.96)%; control group with aspirin and simvastatin: (3.13±0.87)% vs. (5.33±1.25)%, SAP group: (5.68±2.20)% vs. (14.89±2.15)%, ACS group: (7.81±3.96)% vs. (39.27±5.17)%, P<0.05 or P<0.01]. CONCLUSION: The treatment with lipid-modulation and/or antiplatelet drug may significantly decrease the expression of EL, implying that EL participates in the progression of CAD.

[Study on six-minute walk test and cardiac output response against exercise in patients with chronic heart failure].

OBJECTIVE: To evaluate the significance of cardiac output (CO) response against exercise determined by IGR method and LVEF, 6 MWT distance in patients with chronic heart failure (CHF). METHOD: To adopt 6 MWT, and before and after the test measuring the CO by the IGR method, furthermore, measure LVEF to 36 patients (heart failure group) with CHF, compare with the health groups (control group). RESULTS: The 6MWT distance of heart failure group (333.00 +/- 49.64) m decrease compared with the control group (582.56 +/- 67.97) m (P < 0.01), moreover, the distance of NYHA class III (314.82 +/- 36.27) m is significantly shorter than II (361.57 +/- 55.42) m (P < 0.05). The LVEF of heart failure group (47.0 +/- 0.4)% reduce compared with the control group (66.9 +/- 5.2)% (P < 0.01), and the data of NYHA class III (43.3 +/- 10.3)% is significantly lower than II (52.8 +/- 7.6)% (P < 0.01). The increase in CO response against exercise of heart failure group (5.97 +/- 1.89) L/min decrease compared with control group (8.88 +/- 0.52) L/min (P < 0.01), furthermore, the value of NYHA class III (5.31 +/- 1.52) L/min, compared with II (7.01 +/- 1.98)L/min, is obviously lower (P < 0.01). The 6MWT distance correlates positively with the increase in CO response against exercise (r = 0.63, P < 0.01), but the correlation is not found between the increase CO response against exercise and the LVEF (r = 0.11, P > 0.05). CONCLUSION: Our results show that CO response against exercise measured by IGR method, with the advantages of being noninvasive, safe, convenient and accurate, combining with the 6MWT can evaluate cardiac reserve in patient with CHF.

Ferucarbotran versus Gd-DTPA-enhanced MR imaging in the detection of focal hepatic lesions.

AIM: To evaluate the efficacy of ferucarbotran-enhanced MR imaging in the detection of focal hepatic lesions compared to plain and Gd-DTPA-enhanced MR imaging. METHODS: Fifty-nine patients with suspected focal hepatic lesions were admitted to the study. Plain MR imaging (FSE T(2)WI with fat suppression and GRE T(1)WI sequences) and Gd-DTPA dynamic enhanced MR of the liver were initially performed followed by ferucarbotran-enhanced MR imaging 48 h later (including GRE T(1)WI, FSE T(2)WI with fat suppression, and GRE T(2)WI sequences). Images were reviewed independently by three observers. Results were correlated with surgery and pathologic examination or reference examination, and sensitivity was statistically calculated for the different MR imaging sequences. RESULTS: Among all confirmed lesions (n = 133), ferucarbotran-enhanced MR imaging revealed 130 lesions on FSE T(2)WI with fat suppression, 115 lesions on dynamic T(1)WI GRE, and 127 lesions on GRE T(2)WI. Pre-contrast MR imaging revealed only 84 lesions on GRE T(1)WI and 106 lesions on FSE T(2)WI with fat suppression, while Gd-DTPA dynamic enhanced GRE T(1)WI revealed 123 lesions. For 44 micro-lesions (< 1.0 cm) in all patients the detection rates were as follows: ferucarbotran-enhanced FSE T(2)WI with fat suppression, 93.2% (41/44); ferucarbotran-enhanced GRE T(2)WI, 88.6% (39/44); Gd-DTPA dynamic-enhanced GRE T(1)WI, 79.5% (35/44); pre-contrast FSE T(2)WI with fat suppression, 54.5% (24/44); and pre-contrast GRE T(1)WI, 34.1% (15/44). In detecting micro-lesions, statistically significant difference was found for Ferucarbotran-enhanced FSE T(2)WI with fat suppression and GRE T(2)WI sequences compared to the other sequences (P < 0.05). CONCLUSION: Ferucarbotran-enhanced FSE T(2)WI with fat suppression and GRE T(2)WI sequences are superior in detecting micro-lesions (< 1 cm) in comparison with plain and Gd-DTPA dynamic-enhanced MR imaging.

[Changes of fasting serum insulin in normotensive patients with left ventricular hypertrophy].

OBJECTIVE: To explore the relationship between left ventricular hypertrophy (LVH) and serum insulin changes in normotensive patients. METHODS: Forty-two normotensive patients with LVH, who were free of hypertension, coronary artery disease and diabetes, were examined for fasting serum insulin, glucose and serum lipids, and the left ventricular mass (LVM) and left ventricular mass index (LVMI) were also measured with echocardiography, with 46 normal subjects serving as the control group. RESULTS: The levels of fasting triglyceride and insulin, as well as insulin resistance index (IRI), were higher in the LVH group than in the control group. Multifactor regression analysis showed that IRI was positively correlated to LVM and LVMI in LVH group (r=0.38, P<0.01; r=0.29, P<0.01). CONCLUSION: Hyperinsulinemia is closely correlated with LVH in these normotensive patients, and can be involved in the pathogenesis and progression of LVH.

[The effect of ginkgolide B on action potential, L-type calcium current and delayed rectifier potassium current in ischemic guinea pig ventricular myocytes].

AIM: To study the effect of ginkgolide B from Ginkgo leave on action potential (AP), L-type calcium current (I(Ca) - L) and delayed rectifier potassium current (I(K)) in normal and ischemic guinea pig ventricular myocytes. METHODS: With the standard microelectrode technique to record action potential and whole-cell variant patch-clamp technique to record calcium and potassium current. RESULTS: (1) Under normal condition, ginkgolide B shortened APD and had no effect on RP, AP and V(max). Ginkgolide B also increased I(K) in a concentration dependent manner and had no significant effect on I(Ca) - L (2) Under ischemia condition, it was observed that shortening of APD, APA, decrease V(max) and depolarization of RP was induced by ischemia, but ginkgolide B could attenuate above--mentioned changes. (3) Under ischemia condition, I(Ca) - L and I(K) were inhibited, perfusion with ischemia solution containing ginkgolide B could reverse the decrease of I(Ca) - L and I(K). CONCLUSION: Ginkgolide B had protective effect on ischemic myocardium to prevent ischemic arrhythmia.

Enhancement patterns of small hepatocellular carcinoma shown by dynamic MRI and CT.

OBJECTIVES: To study prospectively the enhancement features of small hepatocellular carcinoma (SHCC) with multi-phase scanning of dynamic MRI and spiral CT, and discuss the superiority of dynamic MRI to spiral CT. METHODS: Multi-phase dynamic contrast scanning of high field MRI and spiral CT were performed in 53 patients with SHCC. The arterial phase, portal venous phase and delayed phase scanning of spiral CT was done after the pre-contrast scanning of the entire liver. MRI was performed with SE sequence and fast multiplanar spoiled gradient-recalled sequence dynamic multi-phase contrast scanning. RESULTS: Seventy-six lesions were found in all 53 patients. Sixty-nine and 54 of the 76 lesions enhanced obviously in MRI and spiral CT arterial phase scanning respectively. The typical enhancement patterns of SHCC in the arterial phase, portal venous phase and delayed phase scanning of MRI and spiral CT were hyper-hypo-hypointense (dense) and hyper-iso-hypointense (dense). Atypical enhancement patterns were hyper-hyper-hyperintense (dense), hyper-iso-isointense (dense) and hypo-hypo-hypointense (dense). CONCLUSIONS: Both MRI and spiral CT multi-phase dynamic contrast-enhanced scanning could demonstrate the enhancement features of SHCC, and arterial phase scan of MRI was superior to spiral CT in reflecting the hypervascular characterization of SHCC. In addition, MRI was better than spiral CT in characterization of hepatic lesions combined with SE sequence.