Effects and mechanisms of curcumin on apoptosis of retinal ganglion cells in chronic ocular hypertension rats / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate the effects and mechanisms of curcumin on apoptosis of retinal ganglion cells(RGCs)in chronic ocular hypertension rats.METHODS:A total of 21 Spraque-Dawley(SD)rats were randomly divided into 3 groups with 7 rats in each group. The rat models of chronic ocular hypertension were established by cauterization of the superior scleral veins in the high intraocular pressure model group and the curcumin treatment group, and the sham operation group only cut the conjunctiva without the cauterization of the superior scleral veins; the rats in the curcumin treatment group were intragastrically treated with curcumin at a dose of 4mL/kg, and the rats in the sham operation group and the high intraocular pressure model group were treated with pure water at a dose of 4mL/kg for 3wk. After 3wk, HE staining was used to observe the morphological and pathological changes of retina, the number of RGCs and the thickness of ganglion cell layer(GCL)in each group of rats; TUNEL staining was used to observe the apoptosis of RGCs and retinal cells in each group of rats; the expression levels of glutamate-cysteine ligase modifier subunit(GCLM)and heme oxygenase-1(HO-1)in the retina of each group of rats were detected by real-time fluorescence quantitative PCR, immunohistochemical staining and Western blot.RESULTS:Compared with the sham operation group, the retinal morphology of rats in the high intraocular pressure model group and the curcumin treatment group was disorganized, the number of RGCs was reduced, the GCL was thinner, the apoptosis rate of RGCs and retinal cells increased, and the expression levels of GCLM and HO-1 increased. Compared with the high intraocular pressure model group, the retinal morphology of rats in the curcumin treatment group was basically normal, the number of RGCs increased, the GCL thickened, the apoptosis rate of RGCs and retinal cells decreased, and the expression levels of GCLM and HO-1 increased.CONCLUSION:Curcumin can inhibit the apoptosis of RGCs in the rat model of chronic ocular hypertension by up-regulating the expression of antioxidant genes GCLM and HO-1.

Screening of tumor suppressor genes on 1q31.1-32.1 in Chinese patients with sporadic colorectal cancer / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>As a model for both multistep and multipathway carcinogenesis, colorectal neoplastic progression provides paradigms for researching both oncogenes and tumor suppressor genes (TSGs). However, the mechanism of colorectal cancer (CRC) is not completely understood, and many genes may be involved in the colorectal carcinogenesis. The purpose of this study was to screen for the potential TSGs on chromosome 1q31.1-32.1 in Chinese patients with sporadic colorectal cancer, to explore whether colorectal cancer in the Chinese population has unique genetic alterations and determine whether other putative TSGs exist and contribute to colon carcinogenesis.</p><p><b>METHODS</b>Six polymorphic microsatellite markers, at a density of approximately one marker in every 1.6 cM, were chosen for refined loss of heterozygosity (LOH) mapping of 1q31.1-32.1. Eighty-three colorectal cancer patients' tumor and normal DNA were analyzed via polymerase chain reaction (PCR) for these microsatellite markers. PCR products were eletrophoresed on an ABI 377 DNA sequencer. Genescan 3.1 and Genotype 2.1 software were used for LOH scanning and analysis. On the basis of refined LOH mapping results, we undertook a microarray-based expression screening to identify tumor association genes in 19 of the CRC cases.</p><p><b>RESULTS</b>The average LOH frequency of 1q31.1-32.1 was 24.41%, with the highest frequency of 36.73% (18/49) at D1S2622, and the lowest of 16.42% (11/67) at D1S412. A minimal region of frequent deletion was located within a 2 cM genomic segment at D1S413-D1S2622. There was no significant association between LOH of any marker in the studied regions and the clinicopathological data (patient sex, age, tumor size, growth pattern, or Dukes stage). On the basis of refined mapping results, we chose 25 genes located in the D1S413-D1S2622 (1q31.3-32.1) region and presented a microarray-based high throughput screening approach in 19 sporadic CRC cases to identify candidate CRC related tumor suppressor genes. This study found 4 significantly down-expressed genes, including CSRP1, LMOD1, PPP1R12B and CFHL3. There was no significant association between expression levels of CFHL3, CSRP1, LMOD1, PPP1R12B and the clinicopathological data. By database searching, CSRP1 was hypothesized to be a colorectal cancer related tumor suppressor gene.</p><p><b>CONCLUSIONS</b>Through detailed deletion mapping, we found that the 1q31.3-32.1 region might harbor one or more colorectal cancer related tumor suppressor gene (s). And by microarray-based high-throughput screening of candidate genes located in this region and by subsequent database searching, we present the first evidence that CSRP1 might be involved in the progression of CRC.</p>

Expression of chemokine receptor CXCR4 in colorectal carcinoma and its relationship with clinicopathological parameters / 中华胃肠外科杂志

<p><b>OBJECTIVE</b>To investigate the expression of chemokine receptor CXCR4 in colorectal carcinoma and its relationship with the clinicopathological parameters, and to reveal the role of CXCL12/CXCR4 in the invasion and metastasis of colorectal carcinoma.</p><p><b>METHODS</b>CXCR4 expression was studied in 53 colorectal cancer tissues and 27 normal tissues by immunohistochemistry. Its relationship with clinicopathological characteristics of colorectal cancer patients were analyzed. The CXCR4 expression in tumor and normal specimens and its metastatic sites were assessed by RT-PCR and Western blot.</p><p><b>RESULTS</b>Fifty-three colorectal cancer patients,collected from July 2005 to February 2007 in our hospital,were enrolled in this study. CXCR4 was positive in 39 cancer tissue specimens(73.6%) and its high expression rate (in > 50% of cells) was 45.3%. High CXCR4 expression rate was significantly higher in patients with lymph node metastases (N(1)+N(2): 65.4%) than that in those without metastases(N(0) 25.9%). There were also associations between the high CXCR4 expression and the vascular and lymphatic vessel invasions (P<0.01). Meanwhile, there was a rising trend of high expression rate according to American Joint Committee on Cancer (AJCC) stage and pathologic grade,but no significant difference was found(P>0.05). There were no significant correlation of CXCR4 expression with clinicopathological parameters such as tumor location, tumor size, depth of tumor invasion(P>0.05). In addition, the CXCR4 mRNA expression in primary tumor specimens (n=27) from AJCC stage IIII( patients was significantly higher than that in normal tissues. CXCR4 mRNA expression of liver metastasis specimens(n=5) was significantly higher as compared with the primary colorectal cancer specimens(P<0.01).</p><p><b>CONCLUSIONS</b>Chemokine receptor CXCR4 is associated with the progression of colorectal carcinoma. High CXCR4 expression is associated with metastasis. The CXCL12-CXCR4 signaling pathway may be a potential novel target of therapy for patients with colorectal cancer.</p>

Construction of transcriptome profiling of cancerous parenchyma cells using laser capture microdissection and Gene-Chip technology / 肿瘤

Objective: To construct transcriptome profiling of parenchyma cell using laser capture microdissection (LCM) combined with Gene-Chip technology. Methods: We obtained cancerous parenchyma cells from frozen sections of tumor tissues by using LCM. RNA was extracted from the cells. aRNA was obtained after linear amplification, and then converted to cRNA probe, finally hybridized with Affymetrix HG-U133. Plus 2.0 Gene-Chip for construction of full genome transcriptome profiling. Results: About 3 mm2 cancerous colon cells were obtained from each of 5 colon cancer specimens, respectively. The quantity of total RNA extracted from cancerous colon cells ranged from 118.4 to 300.3 ng. We obtained 7 υg of aRNA after linear amplification from 100 ng mixed RNA. The quality control was guided by the operating instruction standard of Gene-Chip. Totally 18 205 transcripts were presented representing 15 276 genes. Conclusion: The combination of laser capture microdissection and Gene-Chip technology could be used for construction of transcriptome profiling of purified cancerous parenchyma cells.