Guanglong Dong

In silico analysis and verification of S100 gene expression in gastric cancer

BackgroundThe S100 protein family comprises 22 members whose protein sequences encompass at least one EF-hand Ca2+ binding motif. They were involved in the regulation of a number of cellular processes such as cell cycle progression and differentiation. However, the expression status of S100 family members in gastric cancer was not known yet.MethodsCombined with analysis of series analysis of gene expression, virtual Northern blot and microarray data, the expression levels of S100 family members in normal and malignant stomach tissues were systematically investigated. The expression of S100A3 was further evaluated by quantitative RT-PCR.ResultsAt least 5 S100 genes were found to be upregulated in gastric cance by in silico analysis. Among them, four genes, including S100A2, S100A4, S100A7 and S100A10, were reported to overexpressed in gastric cancer previously. The expression of S100A3 in eighty patients of gastric cancer was further examined. The results showed that the mean expression levels of S100A3 in gastric cancer tissues were 2.5 times as high as in adjacent non-tumorous tissues. S100A3 expression was correlated with tumor differentiation and TNM (Tumor-Node-Metastasis) stage of gastric cancer, which was relatively highly expressed in poorly differentiated and advanced gastric cancer tissues (P < 0.05).ConclusionTo our knowledge this is the first report of systematic evaluation of S100 gene expressions in gastric cancers by multiple in silico analysis. The results indicated that overexpression of S100 gene family members were characteristics of gastric cancers and S100A3 might play important roles in differentiation and progression of gastric cancer.

Downregulation of MSP58 inhibits growth of human colorectal cancer cells via regulation of the cyclin D1–cyclin-dependent kinase 4–p21 pathway

We have investigated the expression and role of the 58‐kDa microspherule protein (MSP58) in colorectal carcinoma (CRC). By immuhistochemistry and immunofluorescence, we observed MSP58 in the nucleus and cytoplasm of CRC cells, and found MSP58 to be present in CRC specimens more often than in adjacent non‐tumor tissues (92.5 vs 36.3%, P < 0.01). The average staining score in adjacent non‐tumor tissues was significantly lower than in CRC tissues (2.05 ± 1.13 vs 5.23 ± 1.38, P < 0.01). Moreover, MSP58 mRNA and protein appeared to be upregulated in six fresh CRC samples compared to their adjacent non‐cancerous tissues. MSP58 expression was also detected in the human CRC‐derived cell lines LoVo, CoLo205, HCT116, HT‐29, SW620, and SW480. Downregulation of MSP58 inhibited in vitro growth and attenuated tumor growth in animal models by induction of cell cycle arrest, and was associated with reduced levels of cyclin D1, cyclin‐dependent kinase 4, phosphorylation‐Rb (p‐Rb), p21, and Retino blastoma (Rb) proteins. These results indicated that MSP58 might play an important role in the carcinogenesis of CRC via regulation of the cyclin D1–cyclin‐dependent kinase 4–p21 pathway. (Cancer Sci 2009; 100: 1585–1590)

Notch2 Expression Is Decreased in Colorectal Cancer and Related to Tumor Differentiation Status

BackgroundThe significance of Notch2 expression in colorectal cancer (CRC) has not been clearly investigated. We investigated the expression of Notch2 and its relationship with differentiation status and tumor stage by studying clinical CRC specimens with matched adjacent normal tissues and normal control colorectal specimens.MethodsImmunohistochemistry, real-time polymerase chain reaction, and Western blot analysis were performed to assess the expression of Notch2 in clinical CRC specimens. Also, Notch2 levels in an induced differentiation model of CRC cell lines were investigated.ResultsIt was found that Notch2 expression was decreased in cancer tissues compared with adjacent normal tissue and normal control tissues. Also, a tendency for decreased expression was observed when going from well to poorly differentiated carcinomas, as well as going from tumor, node, metastasis system stage I to stage IV. With the differentiation of colon cancer cells, the expression of Notch2 increased. To support this observation, colon cancer cell lines HT29 and SW620 were induced to differentiate in culture, and expression of Notch2 was investigated. A clear increase expression of Notch2 was observed.ConclusionsNotch2 expression correlated closely with CRC and may play a role in tumor inhibition in colon carcinogenesis.

Notch1 Expression in Colorectal Carcinoma Determines Tumor Differentiation Status

IntroductionThe significance of Notch1 expression in colorectal cancer has not been clearly described. We investigated the expression of Notch1 and its relationship with differentiation status and tumor (Union Internationale Contre le Cancer, UICC) stage using a series of 237 colorectal cancer samples with matched adjacent normal tissues and a series of 46 normal colorectal specimens.Materials and MethodsImmunohistochemistry, real-time polymerase chain reaction, and Western blot analysis were performed to assess the expression of Notch1.ResultsIt was found that Notch1 was overexpressed in cancer tissues as compared with adjacent normal tissue and normal control tissues. Also, a tendency for increased expression was observed when going from well to poorly differentiated carcinomas, as well as going from UICC stage I to stage IV. With the differentiation of colon cancer cells, the expression of Notch1 decreased. To support this observation, colon cancer cell lines HT29 and SW620 were induced to differentiate in culture, and expression of Notch1 was investigated. A clear reduction of Notch1 expression was observed.ConclusionThese results suggest that Notch1 expression correlated closely with colorectal cancer and may play an oncogenic role during colonic carcinogenesis.

The safety of donor in living donor small bowel transplantation – an analysis of four cases

Abstract:  Intestinal transplantation using living‐related donors could potentially reduce the severity of rejection responses against this highly immunogenic organ by better tissue matching and shorter cold ischemia duration, compensating for the shortage of donor grafts. The purpose of this study is to assess the safety of donors receiving living donor small bowel transplantation (LDSBT) in our hospital by reviewing the risk of operations and absorbing capability recovering retrospectively based on the parameters, such as body weight loss, blood loss, blood transfusion, operation time, duration of hospitalization, complications, and d‐xylose tolerance test. After a follow‐up period (mean 72 months, range: 48–96 months) of four cases of donors performed LDSBT in Xijing Hospital of digestive diseases dated from May 1999 to September 2003, no complication occurred. Therefore, pre‐operation angiography, meticulous management of operation and accurate post‐operation monitoring were particularly necessary to guarantee the safety of donors.

Generation of Rat Monoclonal Antibodies Against Human RANTES

RANTES (or regulated upon activation, normal T cell expressed and secreted) belongs to the rapidly growing chemokine family. It is mainly produced by T cells, epithelial cells, monocytes, fibroblasts, and mesanglial cells. Increased RANTES expression has been associated with a wide range of inflammatory disorders and pathologies. Mouse RANTES is the homolog molecule of human RANTES. The two have considerable homology in both sequence and structure. Using hRANTES as immunogen and the technique of rat B lymphocyte hybridoma, we raised two hybridoma cell lines secreting monoclonal antibodies (MAbs) to hRANTES, designated no. 1 and no. 2. Both MAbs can bind the hRANTES in FCM, Western blot analysis, and immunocytochemistry. No. 1 also worked well in immunohistochemistry of rat transplanted intestine, which may recognize the same epitope on human RANTES and rat RANTES. Thus, successful production of rat anti-human RANTES MAbs may provide a useful tool in further exploration of the biological function and pathological significance of RANTES and may provide a new method to judge early rejection after small bowel transplantation.