Photo-sensitive liposomes loading doxorubicin hydrochloride reverse drug resistance of breast cancer / 药学学报

This study was aimed to build a new photo-sensitive co-delivery liposomes which combine photodynamic therapy with chemotherapy to reverse drug resistance of breast cancer. Photodynamic photosen-sitizer chlorin e6 trimethyl ester (Ce6tM) and chemotherapeutic drug doxorubicin hydrochloride (DOX) were loaded into the liposomes (liposomes loaded with Ce6tM and DOX, CDL) by thin-film hydration extrusion and ammonium sulfate active loading methods. CDL was characterized with cryo-transmission electron microscopy (Cryo-TEM), dynamic light scattering particle size, zeta potentials and photo-sensitive DOX release behaviors in vitro. CDL cytotoxicity, singlet oxygen production, DOX accumulation, intracellular ATP level and cell cycle analysis in MCF7/ADR cells were evaluated. Finally, the tissue distribution of DOX and antitumor effects of CDL in BALB/c-nu nude mice bearing MCF7/ADR tumor were investigated. The results showed that the particle size of obtained CDL was 90.7 ± 1.1 nm and distributed uniformly. CDL possessed outstanding properties of photo-sensitive drug release profile. The accumulated release of DOX reached (96.52 ± 0.11)% in 2 min under 671 nm laser irradiation (2 W·cm-2). Interestingly, DOX in CDL could maintain rapid release after 671 nm laser irradiation with low power and short time (15 s, 0.25 W·cm-2). This phenomenon was caused by oxidation of unsaturated phospholipids in CDL under 671 nm laser irradiation and had nothing to do with the slightly elevated temperature. Photo-sensitive drug release behavior contributed to increased DOX accumulation in MCF7/ADR cells. The half inhibition concentration (IC50) of DOX in CDL laser group in MCF7/ADR cells was decreased by 601.9-fold compared with no laser group, which could be related to increased accumulation of DOX, decreased ATP levels and cell cycle arrest in MCF7/ADR cells. With the help of CDL, DOX accumulation in tumor was increased and in cardiac toxicity was reduced in vivo. CDL laser group showed a good anti-tumor effect. The tumor inhibition rate was (94.7 ± 6.2)%. These results suggest that CDL has a promising potential in reversing drug resistance of breast cancer.

Differential expression of the RNA-binding motif protein 3 in human astrocytoma / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The RNA-binding motif protein 3 (RBM3), which is transcriptionally induced by low temperature and hypoxia, has recently been found to be upregulated in human tumors. However, its expression status in human astrocytoma is not well defned. This article focuses on the differential expression of RBM3 in human astrocytomas of different grades and normal brain tissues.</p><p><b>METHODS</b>RBM3 was detected in astrocytomas and normal brain tissues by quantitative real-time PCR, immunohistochemistry, and Western blotting. Analysis of variance was performed on the data from quantitative real-time PCR. The Fisher's exact test was used to analyze the immunohistochemistry results. A P-value of less than 0.05 indicates a statistically significant difference.</p><p><b>RESULTS</b>On one hand, the mRNA expression levels of three X-chromosome-related RBM genes (RBMX, RBM3, and RBM10) were detected by quantitative real-time PCR. The results showed that there were no significant differences in RBMX and RBM10 mRNA expression levels in human astrocytomas of different grades and normal brain tissues. However, RBM3 mRNA expression levels were elevated in high-grade (World Health Organization (WHO) Grade III-IV) astrocytomas versus low-grade (WHO Grade I-II) astrocytomas (5.06 ± 0.66 vs. 1.60 ± 0.58; P < 0.05) or normal controls (5.06 ± 0.66 vs. 1.03 ± 0.22; P < 0.05) as determined by quantitative real-time PCR analysis. On the other hand, immunohistochemistry showed an increased RBM3 labeling index in astrocytomas of different grades and normal brain tissues (positive staining rate: astrocytoma Grade IV, 92.9%; astrocytoma Grade III, 81.8%; astrocytoma Grade I-II, 50%; normal brain tissues, 37.5%; high-grade astrocytoma versus normal brain tissues, P < 0.05; high-grade astrocytoma versus low-grade astrocytoma, P < 0.05). The higher protein levels of RBM3 were also validated in high-grade astrocytomas and low-grade astrocytomas compared with normal brain tissues by Western blotting.</p><p><b>CONCLUSIONS</b>These data suggest that the overexpression of RBM3 may serve as an important molecular mechanism underlying astrocytic carcinogenesis. Moreover, RBM3 may have proliferative and/or proto-oncogenic functions in human astrocytomas.</p>

Preparation, characterization of paclitaxel-loaded Pluronic P105 polymeric micelles and in vitro reversal of multidrug resistant tumor / 药学学报

Drug delivery system (DDS) is a novel approach to overcome multidrug resistance (MDR) in tumors nowadays. This work was designed to investigate a new micellar delivery system for in vitro reversal of resistant ovarian tumor cells, based on a nonionic triblock copolymer Pluronic P105 and paclitaxel (PTX). The PTX-loaded polymeric micelles (P105/PTX) were prepared by thin film-hydration methods. Based on the results of single factor experiments, the P105/PTX micelle formulation was optimized by employing the central composite design-response surface methodology. The physico-chemical properties of the P105/PTX micelles were characterized, including micelle size, drug loading coefficient, in vitro release behavior, etc. The cytotoxicity of the P105/PTX micelles was assessed against human ovarian tumor cell line, SKOV-3/PTX, by a standard 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl (MTT) assay. In order to understand the possible mechanism of Pluronic effects in resistant tumor cells, cellular uptake study of micellar PTX or Rhodamine-123 (R-123) was also carried out. The results showed that the micelle size was about 24 nm with drug loading coefficient of 1.1% and PTX concentration of 700 microg x mL(-1). The cumulative release amount of PTX from the P105/PTX micelles was only 45.4% in 6 h (P < 0.05) and 79.6% in 24 h, whereas Taxol injection in 6 h released 95.2% PTX. The IC50 values of the P105/PTX micelles and Taxol injection against SKOV-3/PTX were 1.14 and 5.11 microg x mL(-1), and resistance reversion index (RRI) was 9.65 and 2.15, respectively. The micellar PTX or R-123 exhibited a significant increase in cellular uptake in resistant SKOV-3/PTX cells compared with free PTX or R-123. These results indicated that PTX could effectively be solubilized by Pluronic P105 block copolymers via thin film-hydration process and formulation optimization, producing nano-scale polymeric micelles with sustained release property in vitro. The P105/PTX micelles were effectively able to reverse resistance to PTX in SKOV-3/PTX tumor cells compared with Taxol injection or free PTX solution, and the enhanced cytotoxicity in the resistant SKOV-3/PTX cell was related to the improved cellular uptake of PTX by Pluronic P105 copolymers.

Localization and distribution of magnetic chemotherapeutic drugs with magnetic targeting in rat brain / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Magnetic targeting therapy may be a new method for the treatment of malignent tumors. The purpose of this study was to investigate the localization and distribution of ferrofluid microsphere of human serum albumin methotrexate (FM-HSA-MTX) carriers in the brain and to explore the magnetic targeting chemotherapy for malignant brain tumor.</p><p><b>METHODS</b>Ninety SD rats were divided into three groups: targeting group, non-magnetic targeting group, and control group. Synthesized FM-HSA-MTX carriers (MTX 25 mg/kg) were injected into the systemic circulation via the caudal vein (magnetic targeting group, n = 30). A 0.6 T magnetic field was placed around the right hemisphere. The non-magnetic targeting group (n = 30) was administered with FM-HSA-MTX without external magnetic field, meanwhile the control group (n = 30) was treated with MTX and a magnetic field. Random serial sacrifices (n = 10) were conducted at 15, 30 and 45 minutes after drug administration. Bilateral hemispheres were collected respectively, and analyzed for total MTX content.</p><p><b>RESULTS</b>MTX content in the right hemisphere of the magnetic targeting group was significantly higher than that in the other two groups at 15, 30 and 45 minutes after drug administration (P < 0.05) No difference was seen between the non-targeting group and control group. In the magnetic targeting group, MTX returned to the peak level [(0.564 +/- 0.018) mg/g, q15-45 = 32.252, P < 0.05] 45 minutes after the injection but it deceased in the other two groups [non-magnetic targeting group: (0.060 +/- 0.015) mg/g, q15-45 = 9.245, P < 0.05, control group: (0.074 +/- 0.045) mg/g, q15-45 = 6.299, P < 0.05]. In the magnetic targeting group, the concentration of MTX in the right hemisphere was significantly higher than that in the left hemisphere (t45min = 21.135, P = 0.000) but no difference was observed between bilateral hemispheres in the other two groups (non-magnetic targeting group: t45min = 0.434, P = 0.670; control group: t45min = 0.533, P = 0.600).</p><p><b>CONCLUSION</b>In the presence of the external magnetic field, FM-HSA-MTX can distribute successfully in the targeting areas of the brain.</p>

Rapid natural resolution of intracranial hematoma / 中华创伤杂志(英文版)

<p><b>OBJECTIVE</b>To investigate the clinical characteristics of intracranial hematoma and the mechanism involved in its rapid natural resolution.</p><p><b>METHODS</b>Seventeen cases of intracranial hematoma with typical clinical and CT manifestations were retrospectively studied.</p><p><b>RESULTS</b>Intracranial hematoma was found obviously decreased in size within 72 h after its occurrence in 8 cases. The rest 9 cases presented complete resolution.</p><p><b>CONCLUSIONS</b>Rapid natural resolution of acute epidural hematoma is mostly found in teenagers and the resolution is correlated with cranial fracture at the hematoma site. As for acute subdural hematoma, its rapid resolution is associated with the transfer of cerebrospinal fluid toward subdural space, the lavage effect, and the compression caused by the increased intracranial pressure or the space left resulting from redistribution of the hematoma in brain atrophy.</p>

Somatic mutations of VHL gene and HIF-1alpha expression in primary renal clear cell carcinomas / 中华外科杂志

<p><b>OBJECTIVE</b>To evaluate the significance of somatic mutations of VHL gene and hypoxia-inducible factor-1alpha (HIF-1alpha) expression in primary renal clear cell carcinoma (RCC).</p><p><b>METHODS</b>Mutation of VHL gene and HIF-1alpha expression were detected by means of PCR, denaturing high-performance liquid chromatography (DHPLC), direct sequencing and immunohistochemistry in 32 samples from primary renal clear cell carcinoma patients.</p><p><b>RESULTS</b>In 32 RCC samples, 17 samples (53.1%) had and 32 samples of adjacent nonmalignant renal tissue had not mutations of VHL gene expression. Twelve RCC samples (70.6%) which had mutations of VHL gene expressed HIF-1alpha, and it had significant difference to 4 RCC (26.7%) samples which didn't have mutations of VHL gene (P < 0.05).</p><p><b>CONCLUSION</b>Mutations of VHL gene may play a significant role in the tumorigenesis of RCC, and HIF-1alpha expression correlates with it.</p>

Construction and screening of suppression subtractive hybridization library of renal cell carcinoma / 中华外科杂志

<p><b>OBJECTIVE</b>To construct and screen the suppression subtractive hybridization (SSH) library of human renal cell carcinoma (RCC).</p><p><b>METHODS</b>Poly A(+) RNA was isolated from RCC lines 786-O (tester) and renal cell (RC) lines HK-2 (driver), respectively. SSH procedure was performed according to the protocol of the PCR-Select cDNA Subtraction Kit (Clontech), and PCR products were cloned into pT-Adv vector and transformed E. coli TOP10F'. All positive clones picked out were digested and some of which were sequenced.</p><p><b>RESULTS</b>The SSH library contained 362 clones with SSH cDNA fragments distributed mainly from 0.3 to 0.9 kb. Among 50 clones sequenced randomly, 2 represented unknown genes and the other 48 derived from 36 known genes.</p><p><b>CONCLUSION</b>The quality of the SSH library of human RCC is reliable and its construction is the basis for further screening differentially expressed genes of RCC.</p>

Expression and significance of clusterin in normal prostate, benign prostate hyperplasia and prostate cancer / 中华外科杂志

<p><b>OBJECTIVE</b>To investigate the expression and significance of Clusterin in normal prostate, benign prostate hyperplasia (BPH) and prostate cancer.</p><p><b>METHODS</b>Clusterin expression in samples of 12 normal prostate, 15 BPH, and 56 prostate cancer were studied by immunohistochemical stain.</p><p><b>RESULTS</b>Of 83 cases, 67 are positive or weak positive (81%). The rate of positive or weak positive for normal prostate, BPH and prostate cancer was 17% (2/12), 73% (11/15), and 96% (54/56) respectively. The expression level of Clusterin in prostate cancer was much higher than in normal prostate (t = 8.82, P < 0.01). BPH (t = 7.63, P < 0.01) was related positively with pathological grade (r = 0.649, P < 0.01) and stage (r = 0.609, P < 0.01) of prostate cancer.</p><p><b>CONCLUSION</b>Clusterin may play an important role in the biological characteristics of prostate cancer by the anti-apoptosis pathway.</p>

Effects of dominant-negative truncation mutant ?NTCF4 on biological characteristics of renal cancer cell line GRC-I by down-regulation Wnt signaling pathway target genes / 中华泌尿外科杂志

Objective To investigate the effects of dominant-negative truncation mutant?NTCF4, lacking the N-terminal form of TCF4 gene,on biological characteristics of renal cancer cell line GRC-I and explore the molecular mechanisms.Methods GRC-I cell was transfected with pCDNA3-?NTCF4 eukary- otie expression plasmid,pCDNA3 empty vector to construct the stable cell line GRC-I/?NTCF4 and GRC-I/ Mock respectively.The morphological changes of stable cells were observed and the cells growth curve was detected through light microscope.The cellular proliferation activities were determined using the MTT assay. The protein expression of Wnt pathway downstream target gene C-Myc and Cox-2 was evaluated by immuno- cytoehemieal method and Western Blot analysis.Results After the dominant-negative?NTCF4 gene was permanently expressed,the GRC-I/?NTCF4 stable cells morphologically showed that appearance changed from circular to long-spindle shape,growth rate decreased with less karyosehisis found,malignant pheno- types reversed to normal renal tubular cells.MTT assay revealed that the proliferation activities of GRC-1/?NTCF4 cells were inhibited by 11.2%-35.5% compared with GRC-I cells (P＜0.05),while the GRC- I/Mock cells have no difference with the control cells.Immunocytochemical analysis and Western Blot showed that the C-Myc and Cox-2 protein expression level of GRC-I/?ANTCF4 cells were significantly sup- pressed in comparison with that of GRC-I/Mock and GRC-I cells.Conclusions The dominant-negative truncation mutant?NTCF4 could partially inhibit the growth of renal cancer cells and down-regulate the pro- tein expression of Wnt pathway target gene C-Myc and Cox-2.These findings provide a experimental founda- tion for applying cell signal therapy to renal cell cancer by blocking the Wnt signaling pathway.

Clinical study on operative effect of traumatic cerebral herniation with bilateral mydriasis / 中华创伤杂志

Objective To explore the surgical effect to traumatic tentorial herniation with bilater- al mydriasis.Methods The patients were divided into three groups,ie,epidural hematoma group,a- cute diffuse brain swelling group and cerebral contusion and/or subdural hematoma group,to perform clinical outcome analysis.Half year after operation,the neurological outcome was scored according to the Glasgow Outcome Scale.Results Of all,there were three cases with good recovery,10 with moderate disability,nine with severe disability and 10 with vegetative survival but 35 deaths.The outcome was the best in epidural hemotoma group but the poorest in acute diffuse brain swelling group.Conclusions The operative effect of traumatic cerebral herniation with bilateral mydriasis is related with the type of orig- inal injury that is important for selection of operation.Patients with cerebral herniation caused by epidural hematoma should receive immediate operation that will induce better outcome.The operation is not vital for those with cerebral herniation caused by acute diffuse brain swelling.Emergent surgery can save lives of some patients with cerebral contusion and/or subdural hematoma.Rapid diagnosis,correct operation and perioperative treatment may ensure the success of surgery.