Silencing Fas-associated phosphatase 1 expression enhances efficiency of chemotherapy for colon carcinoma with oxaliplatin

AIM:To investigate whether silencing Fas-associated phosphatase 1(FAP-1)expression enhances the efficiency of chemotherapy for colon carcinoma with oxaliplatin.METHODS:Expression of FAP-1 in mRNA and protein was detected by reverse transcription polymerase chain reaction(RT-PCR)and flow cytometry.Small interfering RNA(siRNA)was designed according to the FAP-1 mRNA sequence.Cell proliferation was evaluated by methyl thiazolyl tetrazolium(MTT)assay.Anenxin V-and propidine iodine(PI)were assayed by flow cytometry for the detection of apoptosis. RESULTS:The expression of FAP-1 was increased in SW480 cells after chemotherapy with oxaliplatin. Transfection of FAP-1 siRNA into SW480 cells silenced the expression of FAP-1 and consequently abolished the inhibitory function of Fas/FasL-mediated apoptosis pathway,thus increasing the efficacy of chemotherapy for colon carcinoma with oxaliplatin. CONCLUSION:RNA interference combined with conventional chemotherapy is more effective against colon cancer.

Effects of Meloxicam on Vascular Endothelial Growth Factor and Angiopoietin-2 Expression in Colon Carcinoma Cell Line HT-29

To investigate the effect of meloxicam, a selected NSAIDs, on cell growth, expression of VEGF and angiopointin-2 （Ang-2） protein in HT-29 cell line, cultured HT-29 cells were treated with meloxicam of various concentrations for various lengths of time. The proliferation of HT-29 was detected by cell counting kit-8 （CCK-8）, the cell cycle was determined by flow cytometer and the levels of VEGF and Ang-2 protein in supernatants were examined by enzyme linked immunosorbent assay （ELISA）. The mRNA expressions of VEGF and Ang-2 in cultured HT-29 were determined by real-time quantitative reverse-transcription polymerase chain reaction. Our results showed that treatment of meloxicam of different concentrations and for various lengths of time had a cytotoxicic effect on the cell proliferation of HT-29 cells in a concentration-dependant and time-dependant manner. Cell cycle analysis showed that the cells were mainly blocked in G0/G1 phase. The VEGF and Ang-2 protein levels in supernatants of the culture medium were decreased gradually in a concentration-dependent or time-dependent fashion. The mRNA expression of cox-2, VEGF and Ang-2 showed a gradual and concentration-dependent reduction. It is concluded that meloxicam can reduce the expression of VEGF and Ang-2 at the protein and mRNA level in colon carcinoma cell line.

Src Is Dephosphorylated at Tyrosine 530 in Human Colon Carcinomas

Objective：Src is a protein tyrosine kinase that plays important roles in cancer development,and Src kinase activity has been found to be elevated in several types of cancers.However,the cause of the elevation of Src kinase activity in the majority of human colon carcinomas is still largely unknown.We aim at finding the cause of elevated Src kinase activity in human colon carcinomas.Methods：We employed normal colon epithelial FHC cells and examined Src activation in human colon carcinoma specimens from 8 patients.Protein expression levels were determined by Western blotting,and the activity of Src kinase by kinase assay.Results：Actin levels were different between tumor and normal tissues,demonstrating the complexities and inhomogeneities of the tissue samples.Src kinase activities were increased in the majority of the colon carcinomas as compared with normal colon epithelial cells （range 13-29）.Src protein levels were reduced in the colon carcinomas.Src Y530 phosphorylation levels were reduced to a higher extent than protein levels in the carcinomas.Conclusion：The results suggest that Src specific activities were highly increased in human colon carcinomas;phosphorylation at Src Y530 was reduced,contributing to the highly elevated Src specific activity and Src kinase activity.

EXPRESSION OF FLIP IN HUMAN COLON CARCINOMAS: A NEW MECHANISM OF IMMUNE EVASION

Objective： It has been proposed that Fas ligand （FasL） may play an important role in immune escape of tumors and FLIP is an important mediator of Fas/FasL pathway. In this study, the expression of FLIP was determined in human colon carcinoma cell lines and tissue to investigate the new mechanism of immune evasion of human colon carcinomas. Methods： RT-PCR and immunohistochemistry （IHC） were performed to investigate the expression of FLIP in human colon carcinoma cell lines SW480, LS174 and twenty human primary colon carcinoma specimens. Results： It was shown that SW480 cells, LS174 cells and primary colon carcinoma specimen constitutively expressed FLIP at the mRNA and protein level. The expression of FLIP was not found in the epithelial cells of normal colon mucosa. Conclusion： FLIP was expressed in human primary colon carcinoma specimens but not in the normal counterpart. It suggested that the expression of FLIP may occur during the malignant transformation from normal colon epithelial cells to colon carcinoma cells. Tumor cells might obtain the ability to resist the Fas-mediated apoptosis by expressing FLIP. The expression of FLIP might contribute to the formation of colon carcinomas.

Identification of liver metastasis-associated genes in human colon carcinoma by mRNA profiling

Objective: Liver metastasis,which contributes substantially to high mortality,is the most common recurrent mode of colon carcinoma.Thus,it is necessary to identify genes implicated in metastatic colonization of the liver in colon carcinoma.Methods: We compared mRNA profiling in 18 normal colon mucosa(N),20 primary tumors(T) and 19 liver metastases(M) samples from the dataset GSE49355 and GSE62321 of Gene Expression Omnibus(GEO) database.Gene ontology(GO) and pathways of the identified genes were analyzed.Co-expression network and proteinprotein interaction(PPI) network were employed to identify the interaction relationship.Survival analyses based on The Cancer Genome Atlas(TCGA) database were used to further screening.Then,the candidate genes were validated by our data.Results: We identified 22 specific genes related to liver metastasis and they were strongly associated with cell migration,adhesion,proliferation and immune response.Simultaneously,the results showed that C-X-C motif chemokine ligand 14(CXCL14) might be a favorable prediction factor for survival of patients with colon carcinoma.Importantly,our validated data further suggested that lower CXCL14 represented poorer outcome and contributed to metastasis.Gene set enrichment analysis(GSEA) showed that CXCL14 was negatively related to the regulation of stem cell proliferation and epithelial to mesenchymal transition(EMT).Conclusions: CXCL14 was identified as a crucial anti-metastasis regulator of colon carcinoma for the first time,and might provide novel therapeutic strategies for colon carcinoma patients to improve prognosis and prevent metastasis.

FasL EXPRESSION IN HUMAN COLON CARCINOMAS

Objective: The Fas and Fas ligand (FasL) play an important role in maintaining immune privilege on malignant tumors. In present study, we investigated the expression of FasL in SW480 and LS174 human colon carcinoma cell lines and twenty primary colon carcinoma specimens. Methods: The expression of FasL in human colon carcinoma cell lines and primary colon carcinomas specimens was detected by immunohistochemistry and Reverse Transcription-PCR (RT-PCR). Results: We found that all of detected human colon carcinoma cell lines and primary colon carcinoma specimens constitutively expressed FasL at the mRNA and protein level. However, the expression of FasL was not found in normal colon epithelial cells. Conclusion: The expression of FasL may occur during malignant transformation from normal colon epithelial cells to colon carcinoma cells. Our results suggest that tumor cells kill cytotoxic T lymphocytes (CTLS) and natural killer (NK) cells by expression of FasL. It may be a new mechanism for tumor cells to escape the host’s immune surveillance. The expression of FasL may contribute to the formation of colon carcinomas.

Synergistic Action of fMLP-boanmycin Combination on the Growth of Mouse Colon Carcinoma and Its Action Mechanisms

Objective： The inhibitory action of fMLP-boanmycin （BAM） combination on the growth of mouse colon carcinoma and its action mechanisms were observed in order to provide experimental proof for probing novel regimen of chemotactic modulation in combination with chemotherapy in the treatment of cancer. Methods： Cytotoxicity of BAM-fMLP combination to tumor cells was determined by MTT assay in vitro. Antitumor activity of BAM-fMLP combination was assessed in mice subcutaneously transplanted colon carcinoma 26. The amount of superoxide anion （O2 ·^-）released from fMLP stimulated macrophages was determined by NBT assay. The amount of nitric oxide （NO） was indirectly determined by Griess method. Results： BAM-fMLP combination had no synergistic effect on tumor cells（CDI〉0.85）, but BAM at the doses of 10μg/ml, 30μg/ml and 100μg/ml in combination with fMLP at the concentration 20μg / ml exhibited synergistic effect on tumor cells in the presence of macrophages（CDI〈0.75）, fMLP inhibited the growth of colon carcinoma 26 by 50.0% when it at dose of 1 mg/mouse was administered peritumorally. BAM （1 mg/kg, intraperitoneally, three times） alone and BAM - fMLP combination inhibited the growth of colon carcinoma 26 by 38.6% and 78.4%, respectively （CDI=0.71） on day 12. The amount of O2 ·^- released from fMLP 4.6×10^-7 mol/L （0.2μg/ml） stimulated macrophages which were treated by BAM in vitro increased significantly（P〈0.01）, fMLP 2.3×10^-6 mol/L （1μg/ml） could not stimulate macrophages to release NO, but may stimulate macrophages treated with BAM 10μg/ml and 100μg/ml to release NO significantly（P〈0.01）. Conclusion： The inhibitory action of fMLP-boanmycin combination on the growth of mouse colon carcinoma have synergism, which may associate with the increase of O2 ·^- and NO released by macrophages. Chemotactic modulation in combination with chemotherapy may be a novel regimen in the treatment of cancer.

Effect of 5-Aminoisoquinolinone on the Adhesion of Colon Carcinoma

Objective： 5-Aminoisoquinolinone, a water-soluble, potent inhibitor of the activity of poly （adenosine 5＇-diphosphate ribose） polymerase, plays an important role in the tissue injury associated with ischaemia-reperfusion injury and inflammation by inhibiting the activity of poly （adenosine 5＇-diphosphate ribose） polymerase and the expression of cell adhesion molecules such as ICAM-1, P-selectin et al. But how about it in the tumor is not clear. The aim of the present study was to study the effects of 5-Aminoisoquinolinon on the adhesion of colon carcinoma line HT-29 cells to human umbilical vein endothelial cells; and the effects of 5-Aminoisoquinolinon on the expression of ICAM-1, P-selectin and the activity of poly （adenosine 5＇-diphosphate ribose） polymerase in colon carcinoma HT-29 cells. Methods： The adhesion of HT-29 cells to human umbilical vein endothelial cells was detected by adhesive experiment. Immunocytochemically Streptavidin-Peroxidase method was used to investigate the expression of ICAM-1, P-selectin and Poly （adenosine 5＇-diphosphate ribose）（ the product of poly （adenosine 5＇-diphosphate ribose） polymerase activation）. Results： the results of the adhesion assay of HT-29 cells to HUVEC showed that the OD570 value in each 5-AIQ-treated group was significant lower than that in the control group （5-AIQ-untreated） in a dose-dependent manner. The expression of ICAM-1, P-selectin and Poly （adenosine 5＇-diphosphate ribose） was significant lower in 5-Aminoisoquinolinone-treated HT-29 cell group than that in 5-Aminoisoquinolinoneuntreated groups. Conclusion： The data suggest that 5-Aminoisoquinolinone can inhibit the adhesion of HT-29 cells to human umbilical vein endothelial cells. 5-Aminoisoquinolinone also can inhibit poly （adenosine 5＇-diphosphate ribose） polymerase activation and the expressions of ICAM-1 and P-selectin in HT-29 cells. 5-Aminoisoquinolinone probably contributes to the prevention of tumor cell metastasis. Further study is needed.

Effects of Down-regulation of Integrin-β_1 Expression on Migration and Hepatic Metastasis of Human Colon Carcinoma

Organ-specific tumor cell adhesion to extracellular matrix (ECM) components and cell migration into host organs often involve integrin-mediated cellular processes. Direct integrin-mediated cell adhesion to ECM components in the space of Disse appears to be required for the successful liver metastatic formation of colon cancer. In the present study, human colon cancer HT-29 cells were transfected by liposome with integrin-β1 antisense oligodeoxynucleotide (ASODN). The integrin-β1 gene expression in HT-29 cel...

DETECTION OF CANCER-ASSOCIATED ANTIGEN IN FECES USING MONOCLONAL ANTIBODIES IN THE DIAGNOSIS OF COLON CARCINOMA

Monoclonal antibodies against colon and pancreatic cancer, CL-2, CL-3, PS-9, PS-10, were used to detect the associated antigens in feces of patients with gastrointestinal carcinoma and non-cancer diseases. Binding inhibition test by SABC-ELISA method were performed for the measurement of the antigen level. Results showed that the associated antigen detected in feces of patients with colon cancer were significantly higher than that of non-cancer disease or normal subjects. The positive rates were 61.1% as detected with CL-2; 53.4% with CL-3; 55.0%, PS-9; and 53.3% PS-10 in cancer patients while that in normal subjects were 7%; 9%; 8%; and 8% respectively. When 'cocktail' of CL-2, PS-9 and PS-10 were used, the positive rates were 92.5% in colon cancer and 14% in normal subjects. In seven out of the sixty patients with colon cancer studied who were graded as Dukes A, the results were all positive. The results seem superior to the serologic detection and may provide a promising new approach in the early diagnosis of colon cancer.

Laparoscopic versus open right hemicolectomy with curative intent for colon carcinoma

AIM: Laparoscopic surgery, especially laparoscopic rectal surgery, for colorectal cancer has been developed considerably. However, due to relatively complicated anatomy and high requirements for surgery techniques,laparoscopic right colectomy develops relatively slowly. This study was designed to compare the outcomes of laparoscopic right hemicolectomy (LRH) with open right hemicolectomy (ORH) in the treatment of colon carcinoma.METHODS: Between September 2000 and February 2003,30 patients with colon cancer who underwent LRH were compared with 34 controls treated by ORH in the same period. All patients were evaluated with respect to surgeryrelated complications, postoperative recovery, recurrence and metastasis rate, cost-effectiveness and survival.RESULTS: Among 30 LRH, 2 (6.7%) were converted to open procedure. No significant differences were observed in terms of mean operation time, blood loss, post-operative complications, and hospital cost between LRH and ORH groups. Mean time for bowel movement, hospital stay,and time to resume early activity in the LRH group were significantly shorter than those in the ORH group (2.24±0.56vs 3.25±1.29 d, 13.94±6.5 vs 18.25±5.96 d, 3.94±1.64 vs 5.45±1.82 d respectively, P＜0.05). As to the lymph node yield, the specimen length and total cost for operation and drugs, there was no significant difference between the two groups. Local recurrence rate and metachronous metastasis rate had no marked difference between the two groups.Cumulative survival probability at 40 mo in LRH group (76.50%) was not obviously different compared to the ORH group (74.04%).CONCLUSION: LRH in patients with colon cancer has statistically and clinically significant advantages over ORH.Thus, LRH can be regarded as a safe and effective procedure.

Clinicopathologic significance of BAG1 and TIMP3 expression in colon carcinoma

AIM: To explore the expression of BAG1 and tissue inhibitor of metalloproteinase 3 (TIMP3) in colon carcinoma and their correlation and clinicopathologic significance. METHODS: SABC immunohistochemistry was used to detect the expression of BAG1 and TIMP3 in 80 colon carcinoma tissues and 20 normal colonic mucosa. RESULTS: Positive rate of BAG1 in colon carcinoma tissue (80%) was notably higher compared to normal colonic mucosa (10%) (P < 0.05). However, no significant difference was observed in positive rate of TIMP3 in colon carcinoma tissue (43.75%) as compared with normal colonic mucosa (60%) (P > 0.05). Expression of BAG1 and TIMP3 was strongly associated with colon carcinoma differentiation, Duke's staging, lymph node metastasis and survival rate (P < 0.05), but not associated with gender and age. Moreover, BAG1 expression was not correlated with TIMP3. CONCLUSION: Our results suggest that over-expression of BAG1 or attenuated expression of TIMP3 may play an important role in genesis and development of colon carcinoma. The protein expression levels of BAG1 and TIMP3 are related to the malignant degree, infiltration and metastasis of colon carcinoma. BAG1 and TIMP3 might be new biological parameters in predicting invasion and metastasis of colon carcinoma.

Synchronous isolated splenic metastasis from colon carcinoma and concomitant splenic abscess:A case report and review of the literature

This study aimed to describe a case in which an isolated splenic metastasis was synchronous with the colonic primary and a concomitant splenic abscess was associated. A wide review of the literature was also performed. A 54-year-old woman with abdominal pain and fever was admitted to our department. Abdominal CT revealed two low-density areas in the spleen and wall-thickening of the left colonic flexure,which was indistinguishable from the spleen parenchyma. The patient underwent emergency celiotomy,with the presumptive diagnosis of obstructing colon carcinoma of the splenic flexure,and concomitant splenic abscess. Subtotal colectomy and splenectomy were performed. Pathological findings were consistent with mucinous colonic carcinoma,synchronous isolated splenic metastasis and concomitant splenic abscess. This paper is also a review of the existing literature on the association between colorectal cancer and splenic metastasis. Only 41 cases of isolated splenic metastasis from colon carcinoma have been reported in the literature. This report is the third described case of synchronous isolated splenic metastasis from colon carcinoma. Only one case with concomitant splenic abscess has been previously reported. When obstructing left-sided colorectal cancer is suspected,careful CT examination can allow early diagnosis of splenic involvement by the tumor. The literature review suggests that there might be a significant improvement in survival following splenectomy for a metachronous isolated splenic metastasis from colon carcinoma. Prognosis for synchronous splenic metastasis seems to be related to the advanced stage of the disease. Nevertheless,no definitive conclusions can be drawn because of the small number of cases.

Antitumor activity of anti-type IV collagenase monoclonal antibody and its lidamycin conjugate against colon carcinoma

瞄准：包括 MMP-2 和 -9 的类型 IV 胶原酶在癌症房间侵略和转移起一个重要作用并且是为指导 mAb 的治疗的一个吸引人的目标。mAb 3G11 的免疫反应，在人对类型 IV 胶原酶指导的 mAb 渲染表面的癌，被学习由免疫组织化学(IHC ) 染色。mAb 3G11 被结合到反肿瘤抗菌素 lidamycin (LDM ) 。对冒号癌的 3G11-LDM conjugate 的反肿瘤活动在老鼠被调查。方法：ELISA，明胶 zymography，和西方的污点试金被用于 mAb 3G11 的生物描述。有人的 mAb 3G11 的免疫反应渲染表面的癌被染色的 IHC 检测。到人的结肠癌 HT-29 房间的 LDM 和 3G11-LDM conjugate 的细胞毒性被 clonogenic 试金和 MTT 试金检验。conjugate 3G11-LDM 的治疗学的效果与在老鼠的冒号癌 26 被评估。结果：是出现在 ELISA， mAb 3G11 与类型 IV 胶原酶明确地反应了，当 3G11-LDM conjugate 也明确地认出了它的各自的抗原时。在 IHC 试金， mAb 3G11 在颜色的大多数情况中显示出积极免疫反应表面的癌，和在邻近的非恶意的纸巾的否定免疫反应。由明胶 zymography，在类型 IV 胶原酶的分泌物活动的 mAb 3G11 的抑制效果被证明。以在 MTT 试金的 IC50 价值，到人的结肠癌 HT-29 房间的 LDM 的细胞毒性更是 10,000 褶层比丝裂霉素Ｃ(MMC ) 和 adriamycin (ADM ) 的有势力。3G11-LDM conjugate 也极其与 5.6 x 10 的 IC50 价值显示了有势力细胞毒性到人的冒号癌 HT-29 房间(-19) mol/L。在 0.05 和 0.1 mg/kg 的剂量的 3G11-LDM conjugate 分别地在 70.3 和 81.2% 禁止了在老鼠的结肠癌 26 的生长。结论：mAb 3G11 是与有 LDM 的表面的癌和它的 conjugate 是的人的颜色反应的免疫对在老鼠的冒号癌高度有效。

Avidin-biotin system pretargeting radioimmunoimaging and radioimmunotherapy and its application in mouse model of human colon carcinoma

AIM: To evaluate the multi-step pretargeting radioimmunoimaging (RII) and radioimmunotherapy (RIT) in nude mice bearing human colon carcinoma with avidin-biotin system labeled with 153Sm.METHODS: Two- and three-step strategies for avidinbiotin system pretargeting techniques were established.In a three-step procedure, human colon carcinoma bearing nude mice were first injected with biotinylated monoclonal antibody (McAb-Bt) followed by cold avidin (Av) 48 h later and then 153Sm-DB2 24 h thereafter;whereas the twostep procedure consisted of injection of 153Sm-SA 48 h after pretargeting with biotinylated anti-CEA monoclonal antibody (CEA McAb-Bt). SPECT imaging and biodistribution were performed at 4, 24, 48, or 72 h after injection of 153Sm-labeled compounds. Five groups of nude mice subcutaneously grafted with human colon carcinoma were treated 3 d after grafting. One group received the injection with 100 μg CEA McAb-Bt followed by cold avidin (80 μg)after 2 d and 11.1 MBq 153Sm-DB2 after 1d. Four control groups were treated respectively with 11.1 MBq 153SmCEA McAb, 11.1 MBq 153Sm-nmIgG, 11.1 MBq 153Sm-DB2,100 Μl normal saline. Toxicity was evaluated by changes of leukocyte count, and the efficacy by variation in tumor volume. Histological analyses of tumors were performed.RESULTS: The three-step procedure allowed faster blood clearance and yielded higher tumor blood ratios (5.76 at4 h and 12.94 at 24 h) of the 153Sm-DB2. The tumor was clearly visualized at 4 h in y-imaging after the injection of 153Sm-DB2, while a significant accumulation of 153Sm-SA in the tumor was observed only 24 h after the injection and tumor blood ratios at 4 and 24 h were 1.00 and 2.03,respectively, in the two-step procedure. Pretargeting RIT and 153Sm-CEA McAb had a strong tumor-inhibiting effect.The tumor inhibitory rate was 80.67% and 78.44%,respectively, five weeks after therapy. Histopathological evidence also indicated radioactive damage in tumor tissues as necrosis of tumor cells, while in the other organs such as liver and kidney no radioactive damage was observed. Leukocyte counts showed significant decrease after treatment in groups of 153Sm-CEA Mc Ab and 153SmnmIgG.CONCLUSION: The two kinds of pretargeting strategies can elevate the target-to-nontarget ratio, decrease the blood background and shorten the imaging time compared to 153Sm-CEA McAb. Three-step pretargeting RIT is as efficient as 153Sm-CEA Mc Ab, but markedly less toxic. This study provides experimental evidence for the clinical application of pretargeting RII and RIT.

Loss of heterozygosity of Kras2 gene on 12p12-13 in Chinese colon carcinoma patients

瞄准：在中国冒号癌病人在 12p12-13 上学习杂合现象(LOH ) 的损失。方法：DNA 分别地从癌症组织，邻近的组织的 10 个标本和正常组织的 10 个标本的 10 个标本被提取。Kras2 基因的 LOH 被聚合酶链反应(PCR ) 和使中毒的 polyacrylamide 胶化电气泳动在 12p-12-13 上用 11 个微卫星标记分析。结果：Kras 基因的 LOH 在 30% 至少在 12p-12-13 的一个标记上被检测(3/10 ) 邻近的织物标本。LOH 的高频率在 28.57% 在 D12S1034 上被识别(2/7 ) 邻近的织物标本。LOH 至少在一个上被检测癌织物标本的在 60% 的 12p12-13 (6/10 ) 的标记，最经常的 LOH 在 42.86% 在 D12S1034 和 D12S1591 上被发现(3/7 ) 癌织物标本。LOH 在 30% 被检测(3/10 ) 癌组织标本，(3/10 )30% 在 1% 邻近的组织标本，并且不发信号(1/0 ) 癌组织标本。LOH 的出现没与性别，年龄，肿瘤尺寸和淋巴节点转移相关。结论：Genomic 不稳定性可以在冒号癌的发展和前进发生在 Kras2 基因的 12p-12-13 上。Kras2 基因的高 LOH 可以直接影响野类型 Kras2 基因的抄写和翻译。

Reduced expression ofβ-catenin inhibitor Chibby in colon carcinoma cell lines

AIM: To analyse the Chibby expression and its function in colon carcinoma cell lines and colorectal carcinoma (CRC). METHODS: Chibby expression levels were investigated by quantitative RT-PCR in a panel of seven different colon carcinoma cell lines. By sequencing, we analysed mutational status of Chibby. To test whether Chibby exhibited effects onβ-catenin signalling in colon carcinoma cells, we transfected SW480 cells with Chibby expression plasmid and, subsequently, analysed activity of p-catenin and tested for alterations in cellular phenotype. In addition, we examined Chibby mRNA levels in samples of colorectal carcinomas and adjacent normal tissues by using quantitative RT-PCR and hybridised gene chips with samples from CRC and normal tissues. RESULTS: Chibby mRNA expression was strongly down-regulated in colon carcinoma cell lines in comparison to normal colon epithelial cells and no mutation in any of the examined colon carcinoma cell lines was found. Further, we could show that Chibby inhibited p-catenin activity in TOPflash assays when over-expressed in SW480 cells. Proliferation and invasion assays with Chibby transfected SW480 cells did not reveal profound differences compared to control cells. In contrast to these in vitro data, quantitative RT-PCR analyses of Chibby mRNA levels in CRC tumor samples did not show significant differences to specimens in adjacent non-cancerous tissue. Consistent with these findings, gene chips analysing tissue samples of tumors and corresponding normal tissue did not show altered Chibby expression CONCLUSION: Altered Chibby expression might be observed in vitro in different colon carcinoma cell lines. However, this finding could not be confirmed in vitro in CRC tumors, indicating that Chibby is not likely to promote CRC tumor development or progression. As Chibby is an important inhibitor ofβ-catenin signalling, our data implicate that the usability of colon carcinoma cell lines for in vitro studies analysing the Wnt/β-catenin pathway in colorectal carcinoma needs extensive verification.

Cholecystocolic fistula caused by gallbladder carcinoma:Preoperatively misdiagnosed as hepatic colon carcinoma

Cholecystocolic fistula secondary to gallbladder carcinoma is extremely rare and has been reported in very few studies. Most cholecystocolic fistulae are late complications of gallstone disease, but can also develop following carcinoma of the gallbladder when the necrotic tumor penetrates into the adjacent colon. Although no currently available imaging technique has shown great accuracy in recognizing cholecystocolic fistula, abdominopelvic computed tomography may show fistulous communication and anatomical details.Herein we report an unusual case of cholecystocolic fistula caused by gallbladder carcinoma, which was preoperatively misdiagnosed as hepatic flexure colon carcinoma.

Effect of bone marrow-derived monocytes transfected with RNA of mouse colon carcinoma on specific antitumor immunity

AIM: To investigate the effect of bone marrow-derived monocytes transfected with RNA of CT-26 (a cell line of mouse colon carcinoma) on antitumor immunity.METHODS: Mouse bone marrow-derived monocytes were incubated with mouse granulocyte macrophage colony stimulating factor (mGM-CSF) in vitro, and the purity of monocytes was detected by flow cytometry. Total RNA of CT-26 was obtained by TRIzol's process, and monocytes were transfected by TransMessenger in vitro. The activity of cytotoxic T lymphocytes (CTL)in vivo was estimated by the modified lactate dehydrogenase (LDH) release assay.Changes of tumor size in mice and animal's survival time were observed in different groups.RESULTS: Monocytes from mouse bone marrow were successfully incubated, and the positive rate of CD11b was over 95%. Vaccination of the monocytes transfected with total RNA induced a high level of specific CTL activity in vivo,and made mice resistant to the subsequent challenge of parental tumor cells. In vivo effects induced by monocytes transfected with total RNA were stronger than those incuced by monocytes pulsed with tumor cell lysates.CONCLUSION: Antigen presenting cells transfected with total RNA of CT-26 can present endogenous? tumor antigens, activate CTL, and effectively induce specific antitumor immunity.