Objective To study the effect of substance P ( SP) on int racellular f ree calcium concent ration in human poorly-differentiated gast ric cancer cell in vitro. Methods Human gast ric cancer cell line MKN45 was cultured in RPMI 1640. Then the cells were loaded with specific calcium fluorescent probe Furu23/ AM. ASN21377642 (NK21 receptor antagonist) , Nicardipine (calcium channel blocker) and different concent rations of SP were used to treat gast ric cancer cells. The concent ration changes of int racellular free calcium were detected by laser scanning confocal microscope. Results It was found that 10 , 50 and 100 nmol/ L SP could significantly increase the int racellular free calcium concent ration of gast ric cancer cells in Hanks solutions , which contain ext racellular calcium ( P lt;0. 05) , and the change was in a dose-dependent manner ( P lt; 0. 05) . When there was ext racellular calcium existed ,the increasing amplitude of intracellular f ree calcium concent ration was significantly higher than that when there was no extracellular calcium ( Plt; 0. 05) . And when Hanks solutions were pretreated with ASN21377642 and Nicardipine , the effects of 100 nmol/ L SP were partly inhibited , and the concent rations of int racellular f ree calcium were significantly lower than those in group s without pret reatment s ( P lt; 0. 05) . Conclusion SP can significantly increase free calcium concent ration in the gastric cancer cells. Releasing of stored calcium in the cells and influx of extracelluar calcium may contribute to the elevation of int racellular free calcium concentration.
Objective To investigate the role of expression of T cell costimulatory molecule CD28 and variance of T cell subpopulations in the development and prognosis of gastric cancer and colorectal cancer. Methods The peripheral blood lymphocytes were tested for T cell subpopulations and T cell costimulatory molecule CD28 by flow cytometry in 38 patients with gastric cancer, 42 patient s with colorectal cancer , and 21 healthy peoples as control group . Results Expressions of T cell costimulatory molecule CD28 in patients with gastric cancer and colorectal cancer were (25. 80 ±10. 56) % and (28. 95 ±9. 29) % , and significantly higher than that of control group 〔(0. 82 ±0. 98) % , Plt; 0. 01〕. Expression percentage of total T cell (CD3 + ) in patient s with gastric cancer and colorectal cancer were significantly lower than that of control group 〔(53. 61 ±13. 84) % and (55. 96 ±10. 68) % vs (72. 07 ±7. 83) % , Plt; 0. 01〕. Expression percentage of CD4 + T cell (CD4 + CD3 + ) in patients with gastric cancer and colorectal cancer were significantly lower than that of control group 〔( 29. 84 ±9. 71) % and ( 33. 75 ±9. 04) % vs (38. 79 ±5. 08) %; Plt; 0. 01 , Plt; 0. 05〕; Expression percentage of CTL cell (CD8 + CD28 + CD3 + ) in patient s with gastric cancer and colorectal cancer were significantly higher than that of control group 〔( 1. 57 ±1. 99) % and (1. 93 ±2. 61) % vs (0. 02 ±0. 04) %; P lt; 0. 01〕; Expression percentage of CD8 + inhibitory T cell (CD8 + CD28 -CD 3 + ) and CD4 / CD8 ratio in patient s with gastric cancer were significantly lower than that of control group 〔(16. 06 ±6. 94) % vs (20. 56 ±6. 54) % , Plt; 0. 05 ; (1. 10 ±0. 51) % vs (1. 36 ±0. 31) % , P lt; 0. 05〕; Expression of regulatory T cell (CD4 + CD25 + CD3 + ) of patients with colorectal cancer was (19. 74 ±6. 89) % , which was significantly higher than that of control group 〔(13. 72 ±3. 08) % , Plt; 0. 01〕. No difference of expression was found in peripheral T cell subpopulations of postoperative patients with gastric cancer and colorectal cancer after one week ( Pgt; 0. 05) . Conclusion T cell number is fall ,T cell costimulatory molecule CD28 useless expression is increase in patient s with gastric cancer and colorectal cancer. CD4 + T cell subpopulation is significantly decreased in patient s with gast ric cancer. The regulatory T cell of patient s with colorectal cancer is significantly increased.
Objective To evaluate the capability of 64 multidetector CT in the differentiation between mucinous and nonmucinous gastric cancer. Methods From June 2006 to June 2007, 68 patients diagnosed as gastric cancer (18 mucinous and 50 nonmucinous cancer) underwent preoperative scan with a 64-slice helical CT scanner at West China Hospital. The CT images were analyzed retrospectively on tumor location (proximal/distal stomach), diameter of tumor, appearance of thickened gastric wall, contrast enhancement pattern (layered/nonlayered), degree of enhancement and serosal invasion. Results The primarily thickened layer (94% of patients) was the low attenuation middle layer in mucinous cancer and the rate was 72% with high attenuating inner layer or entire layer in nonmucinous cancer. The most common contrast enhancement pattern and degree was layered (83% of patients) and non-enhanced (89% of patients) in mucinous cancer and nonlayered (76% of patients) with enhanced (60%of patients) in nonmucinous cancer. The more common serosal invasion was shown in mucinous cancer than in nonmucinous cancer （89% vs 64%）. These findings were statistically significant (P＜0.05). Tumor location and size of gastric cancer were not correlated with operative pathologic classification. Conclusion Sixty-four multidetector CT is effective in distinguishing mucinous from nonmucinous gastric cancer, predominantly on the basis of thickened and layered gastric wall, enhancement pattern of low-attenuating middle layer.
Objective To observe the effects of vascular endothelial growth factor antisense oligonucleotide (VEGF-ASODN) on expression of vascular endothelial growth factor (VEGF) and growth in gastric cancer cells. Methods The VEGF-ASODN was synthesized artificially with phosphorothioic acid. After transfecting with VEGF-ASODN in gastric cancer cells SGC-7901, the initial copy number of mRNA was detected by real-time RT-PCR, and the quantity of VEGF protein in both cell and supernatant were detected by ELISA. The levels of expression of survivin protein in cells were measured by Western blot. FCM and MTT method were used to detect cellular apoptosis and the activity of cells, respectively. The effect of transfection on the growth of cells was evaluated by growth curve. Results The copy number of VEGR mRNA, protein levels of VEGF in the cells and in culture fluid all decreased when the concentration of transfected VEGF-ASODN increased, as well as the levels of survivin protein （P＜0.05）. The ratio of apoptosis increased, the activity of cells also decreased as the concentration of transfected VEGF-ASODN increased （P＜0.05）. Conclusion Transfection with VEGF-ASODN in gastric cancer cells SGC-7901 can inhibit the expressions of VEGF and survivin remarkably. It can enhance cellular apoptosis and suppress growth of cells.