Objective To explore the effect and mechanism of wortmannin on the human gastric carcinoma cells. Methods SGC7901 cells were treated with 10nmol/L,30nmol/L and 60nmol/L of wortmannin,a specific inhibitor of AKT,for different time periods. Cell viability was estimated by MTT assay. Western blot was used to detect the level of NF-?B neucleoprotein and reverse transcriptasepolymerase chain reaction(RT-PCR) was used to determine transcription of NF-?B mRNA. Results All three different concentrations of wortmannin could inhibit the growth of SGC7901 cells,and the depression effect obviously depended on time and drug dose(P0.05). As the action time of wortmannin was prolonged,neucleoprotein and mRNA expression of NF-?B significantly decreased compared with the control (P

Objective:To investigate the expression of TGF-?1 and its clinical significance in colorectal carcinoma(CRC).Methods:The expression of TGF-?1 in seventy patients with CRC and 10 normal colorectal mucosal tissues were examined by immunohistochemistry,and the expression of TGF-?1 was analyzed with relation to clinicopathologic factors and post-operative survival.Results:Compared with the normal colorectal mucosal tissues,the expression of TGF-?1 in CRC was higher.The overexpression of TGF-?1 is associated with lymph node metastasis,Dukes staging and poor prognosis in patients with CRC.Conclusion:TGF-?1 stimulates CRC cells infiltration and metastasis.The expression of TGF-?1 appears to be a new prognostic factor for the prediction of outcome in patients with CRC.

Objective To observe the effects of oxaliplatin on proliferation in human colon carcinoma cell lines HT29 in vitro and investigate the mechanism. Methods The inhibition of proliferation in HT29 cell was estimated by MTT test. Morphologic changes were observed under electron microscope. Distribution of cell cycle and apoptosis was analyzed by using flow cytometry. The expression of cell cycle protein and apoptosis-associated gene protein was detected with immunohistochemical technique. Results Oxaliplatin could inhibit the proliferation of HT29 cells and the inhibition depended on the exposure dose and time. When treated with oxaliplatin for 72 h, apoptotic cells and apoptotic body could be found under the transmission electronic microscope. The analysis of cell cycle indicated that oxaliplatin blocked cells at G2/M phases and cells of G0/G1 and S phase reduced. The expression of Fas and Bax was up-regulated; Bcl-2, CyclinB1, and PCNA down-regulated. Conclusion Oxaliplatin could inhibit proliferation of the colon carcinoma cell lines HT29. The mechanism of inhibited proliferation is related to the induced apoptosis and the blocked cells.

Objective To analyze the relative risk factors of elderly patients with abdominoperineal resection for rectal carcinoma.Methods The risk factors for hospital death and postoperative complications in 137 elderly patients who had undergone abdominoperineal resection for rectal carcinoma from July 1995 to July 2005 were analyzed retrospectively.Results The risk factors included coexistent diseases,hemoglobin level less than 70 g/L,body mass index(BMI)less than 18.5 kg/m2,intraoperative blood loss more than 1 000 ml,operating time longer than 6 h.The relative risk ratio were 4.76,5.85,6.49,5.47,3.90 respectively for hospital death,and 2.02,2.27,1.83,2.01,1.70 for postoperative complications.Conclusion The risk factors of the elderly patients with abdominoperineal resection for rectal carcinoma should be considered carefully during the perioperative period.

ObjectiveTo construct the eukaryotic expression plasmids of tumor susceptibitity gene(TSG)101-siRNA and investigate the effect of RNA interference targeting tsg101 gene and cisplatin on liver cancer resistant strain QGY/CDDP.MethodsThe targeting fragments specifically against TSG101 were designed according to the principle of small interfering RNA designation using computer software.The sequences were cloned into siRNA expression plasmids through DNA recombinant technology.The expressions of tsg101mRNA and TSG101 after TSG101-siRNA transfection was detected by RT-PCR and Western blot respectively.MTT test were applied to measure the proliferation of QGY/CDDP strain.ResultsThe fragments of interest were obtained by digestion and further confirmed by DNA sequencing.TSG101-siRNA inhibited the expressions of tsg101mRNA and TSG101 and the proliferation of QGY/CDDP,especially in combination with cisplatin.ConclusionThe eukaryotic expression vector of TSG101-siRNA combined with cisplatin inhibits the proliferation of QGY/CDDP and increases the sensitivity of liver cancer resistant strain QGY/CDDP to chemotherapy.

Objective To establish a drug-resistant human colon cancer cell line to oxaliplatin(L-OHP)based on cell line HT29.Methods A resistant cell line-HT29/L-OHP was established by gradually increasing the dose of L-OHP and intermittent administration.The growth curves,multidrug resistance and resistance index of HT29/L-OHP cell line to anticancer agents were detected by MTT assay.The changes of its biological characteristics were determined by light microscopy,electron microscopy,and flow cytometry.Results HT29/L-OHP cell line was established after 3 months,which had stable resistance to L-OHP and a resistance index of 10.64.HT29/L-OHP cells exhibited cross resistance to many other chemotherapeutic agents.As compared with parental cells,the morphological and chromatosome number of HT29/L-OHP were changed;its doubling time was prolonged;and the number of cells in S phase and G0/G1 phase were decreased while in G2/M phase increased.Conclusion HT29/L-OHP cell line shows the typical multidrug-resistant phenotype.

Objective To construct an siRNA expression plasmid against tumor susceptibility gene 101(tsg101) and investigate its effect of RNA interference on oxaliplatin(L-OHP)-resistant human colon cancer cell line HT29/L-OHP.Methods The targeting fragments specifically against tsg101 were designed according to the principle of small interfering RNA designation using an online software.The sequences were cloned into siRNA expression plasmids,and the plasmids were transfected into HT29/L-OHP cells.The expression of tsg101 mRNA after the transfection of TSG101-siRNA plasmid was detected by RT-PCR.The expression of TSG101 after TSG101-siRNA transfection was detected by Western blotting.MTT test was applied to measure the inhibition combined with L-OHP on the proliferation of HT29/L-OHP cells.Distribution of cell cycle was analyzed using flow cytometry after RNA interference to HT29/L-OHP cells.Results The expected fragments were designed,and the TSG101-siRNA plasmid was confirmed by DNA sequencing.The TSG101-siRNA plasmid inhibited the expression of tsg101 mRNA,and the expression of TSG101 protein,and suppressed the proliferation of HT29/L-OHP cells obviously when combined with oxaliplatin.The analysis of cell cycle indicated that the TSG101-siRNA plasmid reduced the cells in G2/M phases and increased the cells in G0/G1 and S phases.Conclusion The expression vector of TSG101-siRNA combined with oxaliplatin inhibits the proliferation of HT29/L-OHP cells and increases the sensitivity to chemotherapy.

Objective To study the distal intramural spread of rectal carcinoma, and provide evidence for modification of rectal carcinoma surgery. Methods Sixty patients with rectal carcinoma admitted to the first affiliated hospital of Chongqing university of medical science from November 2001 to October 2002 were included. The specimens were extended to its original size and shape by the fat clearing method. Mesenteric lymph nodes were dissected by using transillumination to examine metastases histologically, then a lymph nodes map was produced which including the site of the primary lesion, the vascular distribution, and the sites of dissected nodes. The specimen below the distal margin of the tumor was cut continuously with 0.5 cm interval then sectioned for histopathological examination. Results Tumor spread to the distal intramural was observed in 11 of 60 patients (18.3%) with the range within 1.5 cm, of which less than 0.5 cm in 5 case, 5 cm to 1.0 cm in 2 cases, 1.0 cm to 1.5 cm in 4 cases. The tumor invasion was correlated with gross type, histological type and infiltrative depth, but not with sex, age, location of the tumor, size of the tumor, lymph nodes metastases and Dukes stage. Conclusion The range of distal mural excision should exceed 1.5 cm to tumor margin in radical surgery for rectal carcinoma. This rule should be emphasized for patients with poor cell differentiation and deep infiltration.

Objective To investigate the expression and significance of transforming growth factor-?1(TFG-?1) and its correlation with the cellular proliferation activity in human gastric carcinoma (GC). Methods The expression of TGF-?1 and Ki-67 in 50 GC tissues and 10 normal gastric mucosal tissues was examined by immunohistochemistry. Results Compared with the normal gastric mucosal tissues, the expression of TGF-?1 and Ki-67 in GC was significantly higher. TGF-?1 expression was associated with histological differentiation,lymphatic metastasis and invasion depth of GC. And Ki-67 expression was related with lymphatic metastasis and invasion depth of GC too. Furthermore, a significant correlation between TGF-?1 and Ki-67 expressions in GC was found as well. Conclusion Gastric carcinomas with expression of TGF-?1 had high cellular proliferation activity. TGF-?1 could not inhibit cellular proliferation in GC. TGF-?1 stimulated GC cells invasion and metastasis. The overexpression of TGF-?1 and Ki-67 can serve as a reference marker to evaluate GC biological behavior.

Background and purpose: The Testin gene is a candidate tumor suppressor gene located at 7q31.2. Our purpose was to investigate the expression of Testin gene, and its possible relationship with the clinicopathological features of human colorectal carcinoma. Methods: Semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry methods were used to investigate the expression of Testin in 60 specimens of colorectal carcinomas and corresponding adjacent normal mucosal tissues. The correlations of Testin to clinicopathologic features of colorectal carcinoma were analyzed. Results: The mRNA level of Testin was down-regulated in colorectal carcinomas. The positive rate of Testin protein was significantly lower than the paracancerous mucosal normal tissues (P<0.01). The expression of Testin protein and mRNA was correlated with infiltration, differentiation, Dukes stage, T stage,lymph node metastasis and distant metastasis (P<0.05), but not with patients' gender, age, site of cancer (P>0.05). The expression of Testin protein was lower in the tissues which were deeper infiltrated, poorer differentiated, advanced in Dukes stage and T stage, or with lymph node or remote metastasis. The expression of Testin mRNA was positively associated with that of Testin protein(r=0.75,P<0.05). Conclusion: The expression level of Testin is significantly down-regulated in colorectal carcinomas, which may be associated with the degree of infiltration, differentiation and metastasis of colorectal carcinoma. It suggests that Testin may be a valuable marker for assessing the prognosis and metastasis of colorectal carcinoma.