Colon signet-ring cell carcinoma with chylous ascites caused by immunosuppressants following liver transplantation:A case report

BACKGROUND Chylous ascites is caused by disruption of the lymphatic system,which is characterized by the accumulation of a turbid fluid containing high levels of triglycerides within the abdominal cavity.The two most common causes are cirrhosis and tuberculosis,and colon signer ring cell carcinoma(SRCC)due to the use of immunosuppressants is extremely rare in cirrhotic patients after liver transplantation,making it prone to misdiagnosis and missed diagnosis.CASE SUMMARY A 52-year-old man who underwent liver transplantation and was administered with immunosuppressants for 8 months was admitted with a 3-month history of progressive abdominal distention.Initially,based on lymphoscintigraphy and lymphangiography,lymphatic obstruction was considered,and cystellar chyli decompression with band lysis and external membrane stripping of the lymphatic duct was performed.However,his abdominal distention was persistent without resolution.Abdominal paracentesis revealed allogenic cells in the ascites,and immunohistochemistry analysis revealed adenocarcinoma cells with phenotypic features suggestive of a gastrointestinal origin.Gastrointestinal endoscopy was performed,and biopsy showed atypical signet ring cells in the ileocecal valve.The patient eventually died after a three-month follow-up due to progression of the tumor.CONCLUSION Colon SRCC,caused by immunosuppressants,is an unusual but un-neglected cause of chylous ascites.

Three cancers in the renal pelvis,bladder,and colon:A case report

BACKGROUND Multiple primary cancers are rare occurrences that can involve either metachronous or synchronous development.It is particularly rare for an individual to have more than two primary cancers.In this report,we present a case study of an elderly man who was diagnosed with three heterochronous cancers in the renal pelvis,bladder,and colon.CASE SUMMARY On December 30,2014,a 51-year-old Chinese man was admitted to our hospital with complaints of intermittent painless gross hematuria for the preceding week.A computed tomography(CT)scan revealed wall thickening in the left ureter’s upper segment,while a CT urography revealed a left renal pelvis tumor.A successful laparoscopic radical resection of the left renal pelvis tumor was subsequently performed at Shanghai Zhongshan Hospital in January 2015.The pathological findings after the surgery revealed a low-grade papillary urothelial carcinoma of the renal pelvis.The final pathological tumor stage was pT1N0M0.After surgery,this patient received 6 cycles of intravenous chemotherapy with gemcitabine and carboplatin,as well as bladder infusion therapy with gemcitabine.On December 18,2017,the patient was admitted once again to our hospital with a one-day history of painless gross hematuria.A CT scan showed the presence of a space-occupying lesion on the posterior wall of bladder.Cystoscopic examination revealed multiple tumors in the bladder and right cutaneous ureterostomy was performed under general anesthesia on December 29,2017.The postoperative pathological findings disclosed multifocal papillary urothelial carcinoma of the bladder(maximum size 3.7 cm×2.6 cm).The bladder cancer was considered a metastasis of the renal pelvis cancer after surgery.The pathological tumor stage was pT1N0M1.The patient refused chemotherapy after surgery.After another six years,the patient returned on February 28,2023,complaining of periumbilical pain that had lasted six days.This time,a CT scan of the abdomen showed a tumor in the ascending colon,but a subsequent colonoscopy examination indicated a tumor in the descending colon.On March 12,2023,a subtotal colectomy and an ileosigmoidal anastomosis were carried out under general anesthesia.Postoperative pathological findings revealed that all three tumors were adenocarcinomas.The final pathological tumor stage was pT3N0M0.The patient had an uneventful postoperative recovery and was discharged without complications.CONCLUSION The case of this elderly man presents a rare occurrence of metachronous primary cancers in the renal pelvis and colon.Bladder cancer is considered a metastasis of renal pelvis cancer after surgery.Optimal treatment can be implemented by evaluating the patient’s histological features,clinical history,and tumor distribution correctly.

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.

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.

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.

Clear cell adenocarcinoma of the colon is a unique morphological variant of intestinal carcinoma:Case report with molecular analysis

Here we report a new case of clear cell adenocarcinoma (CCA) of the colon in a 54-year-old Caucasian man. Despite of the previous reported cases, the lesion was located in the right colon and was not associated with the conventional adenoma. We performed immunohistochemical and molecular analyses in order to explore whether the CCA had the molecular features generally associated with conventional colorectal carcinoma. The immunohistochemical and molecular analyses showed that the different morphology of CCA does not reflect a distinct biological entity but only an unusual morphological variant of intestinal carcinoma.

Clear cell adenocarcinoma of the colon:A case report and review of literature

A primary clear cell adenocarcinoma of the colon is a rare oncologic entity. We herein report a case of such a tumor of the sigmoid colon in a 71-year-old woman who was successfully treated by an endoscopic polypectomy in our hospital. We also reviewed the published reports regarding cases of primary clear cell tumors in the colon.

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.

Mucinous cystadenoma of the appendix associated with adenocarcinoma of the sigmoid colon and hepatocellular carcinoma of the liver:Report of a case

附录的粘蛋白的包囊腺瘤是一个稀罕条件并且与附录的普通名字粘液囊肿代表三个实体之一。它被腔的膀胱的膨胀在它内与粘液的壅滞描绘。组织病理学说地，粘液囊肿被划分成三个组：焦点或弥漫的粘膜增生，粘蛋白的包囊腺瘤和粘蛋白的包囊腺癌。这个条件经常与另外的瘤形成被联系，特别冒号和卵巢的腺癌。我们这里描述与腹的不快，便秘，在凳子的新鲜的血和经常的泌尿介绍了的 57 岁男性病人。他有与结肠的腺癌和肝的肝细胞癌联系的附录的一个大包囊腺瘤。病人经历了正确 haemicolectomy， S 字形的冒号切除术和肝的部分切除术。现在， 3 年以后，他没有疾病恶化的证据。根据这，我们在这些病人强调精确外科手术前的诊断的需要和整个腹部的 intraoperative 探索。

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.

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.

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.

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.

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.

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。

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.

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。

Docosahexaenoic acid suppresses arachidonic acid-induced proliferation of LS-174T human colon carcinoma cells

AIM:To investigate the impact of arachidonic acid (AA) and docosahexaenoic acid (DHA) and their combination on colon cancer cell growth.METHODS:The LS-174T colon cancer cell line was used to study the role of the prostaglandin precursor AA and the omega-3 polyunsaturated fatty acid DHA on cell growth. Cell viability was assessed in XTT assays. For analysis of cell cycle and cell death,flow cytometry and DAPI staining were applied. Expression of cyclooxygenase-2 (COX-2),p21 and bcl-2 in cells incubated with AA or DHA was examined by real-time RT-PCR. Prostaglandin E2 (PGE2) generation in the presence of AA and DHA was measured using a PGE2-ELISA.RESULTS:AA increased cell growth,whereas DHAreduced viability of LS 174T cells in a time-and dose-dependent manner. Furthermore,DHA down-regulated mRNA of bcl-2 and up-regulated p21. Interestingly,DHA was able to suppress AA-induced cell proliferation and significantly lowered AA-derived PGE2 formation. DHA also down-regulated COX-2 expression. In addition to the effect on PGE2 formation,DHA directly reduced PGE2-induced cell proliferation in a dose-dependent manner. CONCLUSION:These results suggest that DHA can inhibit the pro-proliferative effect of abundant AA or PGE2.