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Objective To investigate the clinicopathological significance of PDC in liver metastases and analyze the correlation of PDC between liver metastases and primary lesions. Methods Retrospective analysis of 72 matched cases of colorectal cancer with liver metastases was performed. The PDC in primary tumor and liver metastatic lesion was interpreted synchronously, and then the relationship between PDC in liver metastasis and clinicopathological parameters was analyzed based on the correlation of PDC between primary and metastatic lesions. In addition, PDC were interpreted in accordance with Uenos' standard. Results Among the 72 cases of liver metastasis of colorectal cancer, the number of G1, G2, and G3 graded by PDC was 28, 24, and 20, respectively. The PDC in liver metastatic lesion was correlated with tumor budding in liver metastatic lesion and PDC grade of primary lesion. No significant correlation with the size and number of liver metastatic lesion, the site, WHO grade, depth of invasion, lymph node metastasis, vascular invasion or tumor budding of the primary lesion was observed. Conclusion A positive correlation is found between liver metastasis of colorectal adenocarcinoma and PDC grade of primary tumor. Evaluating the PDC grade of primary tumor may provide a reference for the risk of liver metastasis.
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Objective To investigate the effect of ketamine on the mitochondrial function of rat neurons subjected to anoxia. Methods Primarily cultured rat hippocampal neurons were seeded in culture dishes (35 mm in diameter) at the density of 5×105-1×106 cells∕ml, and divided into 3 groups (n=11 each) using a random number table: control group, anoxia group and ketamine group. The neurons were exposed to 90% N2 plus 10% CO2 50 ml∕min for 5 min in anoxia group. In ketamine group, ketamine was added to the culture medium with the final concentration of 20 μmol∕L at 1 h before anoxia, and then the neurons were exposed to 90% N2 plus 10% CO2 50 ml∕min for 5 min. After the end of treatment in each group, the dead neurons were detected using trypan blue staining, the ATP content was determined by ATP bioluminescence assay, and mitochondrial membrane potential was measured by rhodamine 123 staining. Results Compared with control group, the mortality rate of hippocampal neurons was significantly in?creased, and the ATP content and mitochondrial membrane potential were significantly decreased in anoxia group and ketamine group ( P<0.05) . Compared with anoxia group, the mortality rate of hippocampal neu?rons was significantly decreased, and the ATP content and mitochondrial membrane potential were signifi?cantly increased in ketamine group (P<0.05). Conclusion The mechanism by which ketamine amelio?rates anoxia?induced damage to rat neurons is related to improved mitochondrial function.
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Objective To investigate the drug resistance of side population cells in human gallbladder cancer cell line GBC-SD and explore its mechanism. Methods Drug sensitivity assays of 5chemotherapeutic agents were performed on side population cells (SP) and non-SP cells of GBC-SD.GBC-SD was cultured and then treated with the chemotherapeutic agent gemcitabine. The frequency of SP by FACS was measured. RT-PCR and Western blotting were used to detect the expression of AB-CG2 in both the SP and the corresponding non-SP subsets. Results After 1 d treatment with 4 chemotherapeutic agents (gemcitabine, cisplatin, 5-fluorouracil and mitoxantrone) in IC50 concentration to GBC-SD cell line, the reproductive ability of SP was higher than that of non-SP (P0.05). The percentage of SP in GBC-SD treated with chemotherapeutic agent gemcitabine after 3 weeks was sharply elevated by FACS (8.02% ±0.13% vs 0.62% ±0.08%, P<0.05), and the expression of ABCG2mRNA and protein were increased in SP as compared with non-SP. Conclusion SP from human gallbladder cancer cell line GBC-SD, like stem cell, showed a heighten resistance to drugs. Increased expression of ABCG2 was largely responsible for the multi-drug resistance.
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ObjectiveTo explore the tumor igenic property of side population cells (SP) from human gallbladder carcinoma cell line GBC-SD. Methods SP and non-SP cells were isolated from GBC-SD staining with Hoechst33342 dye by fluorescence-activated cell sorting (FACS). The soft agar clonal assay and xenograft assay were performed to characterize tumorigenic property of side population cells in vitro and in vivo, respectively. The percentage of SP cells was analyzed by FACS in 5 hu man gallbladder carcinoma specimens. ResultsThe percentage of SP cells accounted for approximately 0.87 ％ of GBC-SD cells. The clone-formed rates of SP was more frequent than that of non-SP cells (14.74％ ± 3.53％ vs 5.17％ ± 1.05％), there was statistically significant difference (t =2.75,P＜0. 05). SP cells could generate tumors with as few as 5 × 103 cells (four of seven animals), whereas at least 1 × 105 non-SP cells were needed to form a tumor (one of seven animals). Re-analysis of SPderived tumors by FACS showed that SP cells under in vivo conditions also have the capacity to regenerate the SP and non-SP fractions. Besides, analysis of Hoechst33342 revealed s small fraction of SP cells, ranging from 0. 27％ to 2.3％ in gallbladder carcinoma specimens. ConclusionSP cells from GBC-SD are highly tumorigenic similar as the cancer stem cells.
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Objectives To isolate cancer stem cells (CSCs) in pancreatic cancer cell lines PANC1 and ASPC-1 with serum-free medium( SFM ), and to detect the expression of miR-590-3p in CSCs. Methods PANC1 and ASPC-1 cells was cultured in serum-free medium. The monoclonal formation, differentiation and cell cycle, half inhibitory concentration ( IC50 ), and the expression of the surface markers CD24 + , CD44 + were detected. qRT-PCR was used to detect the expression of miR-590-3p. Results After SFM culture, (0.94 ±0.53 ) ％ of ASPC-1 and (0.57 + 0. 12 ) ％ PANC1 survived, and they formed spheres, and could continuously passage in vitro. Cell spheres differentiation recurred when serum was supplemented in SFM. The G0/G1 stage proportion, CD24+ , CD44 + , CD24+ CD44+ cells proportion, IC50 in ASPC-1 cell were (75.3 ± 5.4)％,0.96％ ～ 2.01％, 27.52％ ～ 34.47％, 0.35％ ～ 0.44％ and (224.37 ± 5.71 ) μg/ml, which were significantly higher than that those in parent cell [ (43.7 ± 3.8 ) ％, 0. 38％ ～ 0.42％, 17.65％ ～ 18.25％,0.05％ ～0.08％, (11.43 ±2.10)μg/ml, P＜0.05]. The G0/G1 stage proportion, CD24+ ,CD44+ ,CD24 +CD44 + cells proportion, IC50 in PANC 1 cell were ( 80. 1 ± 4.7) ％, 5.31％ ～ 9.84％, 72.05％ ～ 93.06％,4.91％ ～5.21％, (296.58±4.27) μg/ml, which were significantly higher than that those in parent cell [ (46.1 ±5.3)％, 4.09％ ～4.97％, 47.71％ ～55.66％, 1.48％ ～2.63％, (26.17 ±3.81)μg/ml, P＜0.05]. The expression of miR-590-3p in ASPC-1, PANC1 spheres was 4.67 and 4.52 times higher than the expression in parent cell lines. Conclusions Pancreatic cancer cell spheres can be isolated from ASPC-1, PANC1 by culture with SFM. miR-590-3p is up-regulated and may play an important role in regulating biological characteristics of pancreatic cancer stem cells.
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Mounting evidence has shown that side population (SP) cells are enriched for cancer stem cells (CSCs) responsible for cancer malignancy. In this study, SP technology was used to isolate a small subpopulation of SP cells in human gallbladder cancer cell line GBC-SD, and SP cells which had superior potential for proliferation in vitro and tumorigenesis in vivo were identified. Importantly, the abundance of GBC-SD SP cells was increased by a transforming growth factor-β (TGF-β)-induced epithelial-mesenchymal transition (EMT), and this effect was accompanied with a strong up-regulation of ABCG2 mRNA expression, and a decreased sensitivity to mitoxantrone. SP cells were restored upon the removal of TGF-β and the reversion of the cells to an epithelial phenotype, and smad3-specific siRNA reduced SP abundance in response to TGF-β. In conclusion, TGF-β-induced EMT by smad-dependent signaling pathway promotes cancer development and anti-cancer drug resistant phenotype by augmenting the abundance of GBC-SD SP cells, and a better understanding of mechanisms involved in TGF-β-induced EMT may provide a novel strategy for preventing cancer progression.