Potential Application of Eicosapentaenoic Acid Monoacylglyceride in the Management of Colorectal Cancer

Background: There is increasing evidence that marine omega-3 oils are involved in the reduction of cancer risk and progression. However, the anticancer effect of omega-3 monoglyceride on colorectal cancer has yet to be assessed. The goal of this study was to evaluate the anti-cancer effects of eicosapentaenoic acid monoglyceride (MAG-EPA) in HCT116 colorectal carcinoma cells. Methods: The effect of MAG-EPA was evaluated in vitro on HCT116 cells and in vivo on mouse model of HCT116 xenograft. Results: Our data reveal that MAG-EPA decreased cell proliferation and induced apoptosis in HCT116 cells. In a xenograft mouse model, daily per os administration of MAG-EPA reduced tumor growth. Furthermore, MAG-EPA treatments decreased EGFR, VEGFR, and AKT activation pathways and reduced VEGF and HIF1α expression levels in tumors. Conclusion: MAG-EPA may promote apoptosis and inhibit growth of tumors by suppressing EGFR and VEGFR activation pathways. Altogether, these data provide new evidence regarding the mode of action of MAG-EPA in colorectal cancer cells.

[Expression of vascular growth factors in intestinal tissues in colorectal carcinoma patients with schistosomiasis japonica]

OBJECTIVE

To investigate the differences of mRNA quantitation and protein expression of vascular growth factors including platelet-derived endothelial cell growth factor (PD-ECGF) and vascular endothelial growth factor (VEGF) in intestinal tissues in colorectal carcinoma patients with and without schistosomiasis.

METHODS

Thirty colorectal carcinoma patients with schistosomiasis and 30 colorectal carcinoma patients without schistosomiasis were included in this study. The mRNA quantitation and protein expression of PD-ECGF and VEGF in the normal tissue, peri-carcinoma tissue as well as carcinoma tissue obtained from surgical specimens were detected by qRT-PCR and Western blot.

RESULTS

The mRNA relative quantitations of PD-ECGF in normal tissue, peri-carcinoma tissue and carcinoma tissue in the colorectal carcinoma patients with schistosomiasis were 1.726, 1.766 and 2.729 times to those in the colorectal carcinoma patients without schistosomiasis, respectively. The corresponding ones of VEGF were 2.138, 1.831 and 3.376 times, respectively. The protein expression levels of PD-ECGF and VEGF in normal tissue, peri-carcinoma tissue and carcinoma tissue were higher in the colorectal carcinoma patients with schistosomiasis than in the colorectal carcinoma patients without schistosomiasis.

CONCLUSIONS

The expressions of vascular growth factors including PD-ECGF and VEGF are higher in the colorectal carcinoma patients with schistosomiasis than in the colorectal carcinoma patients without schistosomiasis. Therefore, schistosomiasis may be one of the risk factors of colorectal cancer.

Colorectal carcinoma associated with schistosomiasis: a possible causal relationship

The association between schistosomiasis and colorectal malignancy has long been suggested in the literature, but it is not uniformly accepted. In the Far East, considerable evidence supports an etiological link between Schistosoma japonicum and colorectal cancer. However, the available data regarding the role of Schistosoma mansoni in colorectal carcinogenesis are conflicting and most often do not show causality. We report on a patient with sigmoid colonic cancer coexisting with schistosomiasis, and we provide a comprehensive review of the literature regarding the epidemiology and pathobiology of this association.

Colorectal cancer in a population with endemic Schistosoma mansoni: is this an at-risk population?

PURPOSE

Chronic infection with schistosomiasis has been clearly associated with the development of bladder cancer, and infestation is associated with a high incidence of colorectal cancer in endemic populations. Despite this association, the potential role of alterations in tumor suppressor genes colorectal cancers has never been evaluated in an endemically infected population. The aim of this paper was to compare histopathologic and genetic changes in schistosomal colitis-associated colorectal cancer (SCC) with colorectal cancer in a group of patients from the same population not affected by the disease (NDCC).

MATERIALS AND METHODS

Sixty patients were included in this study: SCC-40, NDCC-20. Data collected included age, sex, clinical presentation, presence of synchronous tumors, histopathology, and clinical stage. p53, DCC (deleted in colorectal cancer gene), and mismatch repair genes (MLH1 and MSH2) were studied using immunohistochemical staining.

RESULTS

Patients with SCC were significantly younger than the NDCC group (34.52+/-11.22 years vs 50.73+/-12.75 years, p=0.02). Mucinous adenocarcinoma occurred significantly more frequently in SCC (35 vs 10%, p=0.02). SCC tumors were more frequently stage III or IV, and significantly more synchronous tumors were present in the affected group (SCC-8/40 vs NDCC-1/20, p=0.05). p53 staining was far more frequent in SCC (SCC-32/40 vs NDCC-8/20, p=0.006). DCC expression was similar in two groups. There were only four cases, three in SCC and one in NDCC, that showed microsatellite instability.

CONCLUSION

The data suggest that schistosomal colitis is more commonly associated with earlier onset of multicentric colorectal cancer, high percentage of mucinous adenocarcinoma, and presents at an advanced stage. The identification of a higher incidence of altered p53 expression in the SCC group raises the possibility of an association between schistosomiasis and alterations in p53 activation as an inciting event in colorectal cancer development.

Acute colorectal obstruction treated by means of transanal drainage tube: effectiveness before surgery and stenting

OBJECTIVES

The aim of this study was to clarify the usefulness of the management of acute colorectal obstruction using a transanal drainage tube before surgery or stenting.

METHODS

Fifty-four patients (34 males and 20 females, aged 46-94 yr, mean = 69.7) treated between May 1998 and March 2004 for acute colorectal obstruction were identified in a colorectal obstruction database, and their clinical and radiological features were reviewed. Based on abdominal computed tomography findings, urgent colonoscopy was performed. Subsequently, endoscopic decompression using a Dennis Colorectal Tube (DCT) was attempted.

RESULTS

Endoscopic decompression using the DCT was technically successful in 52 of 54 patients (96.3%). The site of obstruction was the cecum in 4, the ascending colon in 2, the transverse colon in 7, the descending colon in 11, the sigmoid colon in 18, and the rectum in 12. The etiology of obstruction was primary colorectal carcinoma in 45, non-colonic metastatic carcinoma in 4, postoperative obstruction in 4, and retrograde intussusception in 1. Following adequate cleansing of the colon, 44 patients underwent a one-stage surgery after 7+/- 3 days (SD; range, 4-10 days). Stenting was successfully used as the final palliative treatment in 4. The use of the DCT alone relieved postoperative stenosis (3 patients) and retrograde intussusception (Prognosis in patients with obstructing colorectal carcinoma. Am J Surg 1982;143:742-7). During these treatments, perforation occurred in one patient with postoperative stenosis of the cecum.

CONCLUSIONS

Management of acute colorectal obstruction using the DCT was found to be effective and safe, irrespective of the site or etiology of the obstruction. Therefore, this procedure should be considered as a primary method for decompression of the obstructed colon before considering surgery or stenting.

Phase I and pharmacokinetic study of the polyamine synthesis inhibitor SAM486A in combination with 5-fluorouracil/leucovorin in metastatic colorectal cancer

PURPOSE

The purpose of our study was to determine the maximum-tolerated dose, dose-limiting toxicity, safety profile, and pharmacokinetics of the polyamine synthesis inhibitor SAM486A given in combination with 5-fluorouracil/leucovorin (5-FU/LV) in cancer patients.

EXPERIMENTAL DESIGN

Patients with advanced colorectal cancer were treated with 5-FU [bolus (400 mg/m(2)) followed by a 22-h infusion (600 mg/m(2))] and LV (200 mg/m(2)) and escalating doses of SAM486A, 1-3-h infusion daily for 3 days. Plasma sampling was performed to characterize the pharmacokinetics and pharmacodynamics of the combination

RESULTS

Twenty-seven patients with metastatic colorectal cancer and 1 with pseudomyxoma peritonei were treated. Twenty-six patients received SAM486A in the combination at doses ranging from 25 to 150 mg/m(2)/day. Dose-limiting toxicity consisting of fatigue grade 3 was seen at 150 mg/m(2)/day. Other adverse events included neutropenia, hand and foot syndrome, nausea, vomiting, diarrhea, and constipation. Fifteen of 26 patients evaluable for best response according to the Southwest Oncology Group criteria achieved a partial response [8 (30%) of 26] or stable disease [9 (35%) of 26]. SAM486A did not influence the pharmacokinetics of 5-FU, and SAM486A clearance was similar to that when used as a single agent.

CONCLUSIONS

The novel molecular agent SAM486A is tolerable and safe in combination with a standard 5-FU regimen in patients with advanced colorectal cancer. The dose of SAM486A recommended for additional studies with this combination is 125 mg/m(2)/day. A disease-directed evaluation of SAM486A using this regimen is warranted.

Histological classification of schistosomal egg induced polyps of colon and their clinical significance. An analysis of 272 cases

272 cases of schistosomal egg induced polyps collected from mass-screening for colorectal carcinoma in Jiashan County were divided into 3 types: fibrous type (FT), mixed type (MT) and epithelial proliferative type (ET). The ET was characterized by crypt elongation, hypertrophy, variation in size, disorderly arrangement, as well as the high percentage of atypical hyperplasia (64.9%). The coexistence and transition between inflammatory reactive hyperplastic and neoplastic crypts were noticed. By HID/AB staining, sialomucins were increased in ET, CEA and PNA receptors detected by the ABC method were present in 18/20 and 6/18 of ET respectively. The mucin expression of ET was similar to that of adenomas. It is likely that a spectrum of ET, atypical hyperplasia and adenoma may exist. We suggest that the patients with ET, especially those with atypical hyperplasia, should be regarded as "risk group", and close follow-up is needed.