Colorectal cancer screening and surveillance

In vitro/in vivo biorecognition of lectin-immobilized fluorescent nanospheres for human colorectal cancer cells

Peanut agglutinin (PNA)-immobilized polystyrene nanospheres with surface poly(N-vinylacetamide) (PNVA) chains encapsulating coumarin 6 were designed as a novel colonoscopic imaging agent. PNA was a targeting moiety that binds to beta-D-galactosyl-(1-3)-N-acetyl-D-galactosamine, which is the terminal sugar of the Thomsen-Friedenreich antigen that is specifically expressed on the mucosal side of colorectal cancer cells. PNVA was immobilized with the aim of reducing nonspecific interactions between imaging agents and normal tissues. Coumarin 6 was encapsulated into nanosphere cores to provide endoscopically detectable fluorescence intensity. After incubation of imaging agents with human cells, the fluorescence intensity of imaging agent-bound cells was estimated quantitatively. The average fluorescence intensity of any type of colorectal cancer cell used in this study was higher than that of small intestinal epithelial cells that had not exposed the carbohydrate. The in vivo performance of imaging agents was subsequently evaluated using a human colorectal cancer orthotopic animal model. Imaging agent-derived strong fluorescence was observed at several sites of the large intestinal mucosa in the tumor-implanted nude mice after the luminal side of the colonic loop was contacted with imaging agents. In contrast, when mice that did not undergo tumor implantation were used, the fluorescence intensity on the mucosal surface was extremely low. Data indicated that imaging agents bound to colorectal cancer cells and the cancer cell-derived tumors with high affinity and specificity.

Delivery of a polyp

BACKGROUND

Colorectal cancer is uncommon during pregnancy. Although there is overlap between symptoms of colon cancer and normal pregnancy, clinicians should be vigilant identifying those at risk and offer colorectal cancer screening when appropriate.

CASES

Three women in their 30s passed or prolapsed adenomatous tissue per rectum during the second stage of labor. Further evaluation lead to the diagnosis of premalignant lesions or colorectal cancer in each case.

CONCLUSION

Colorectal cancer can present in young women of childbearing age, especially in those with a genetic predisposition. It may present with the prolapse or passage of tissue during vaginal delivery. Appropriate referral and screening are of critical importance for those at risk, especially those with a family history or pertinent physical findings.

Surgical approaches to cancer in patients who have inflammatory bowel disease

IBD clearly increases the risk for GI malignancies, especially CRC. The absolute number of patients that develops such malignancies is low compared with the overall cancer rate; however, younger age of onset, higher relative risk, unique clinical presentations, and problems with early diagnosis make this a serious complication of IBD. With the exception of patients with comorbid complications, such as primary sclerosing cholangitis, the prognosis is no worse for CRCs that arise as the result of IBD compared with those that arise sporadically. The prognosis remains poor for small bowel adenocarcinomas in patients who have CD, primarily because of their advanced stage at detection. Diligent surveillance is essential for early detection and treatment of IBD-related CRCs in patients with unresected colons, long-standing or extensive disease, and in those who have early-onset CD, although pundits still question whether it significantly affects prognosis and survival. Better surveillance techniques for small bowel dysplasia or malignancy in patients who have CD is needed, especially given the poor prognosis of these patients when advanced cancers are detected. Depending on the presentation and disease diagnosis, patients have several surgical treatment options and can expect good outcomes for all. When the appropriate surgical technique is used in patients who have colon or rectal cancer, along with adjuvant chemotherapy when appropriate, prognosis and function is good; however, the experience of the surgeon can affect the prognosis for IBD-related GI cancers. Surgical therapy is based not only on general oncologic principles, but also on the surgery that is appropriate for the IBD diagnosis. Resection of the mesentery and lymphadenectomy should be performed according to oncologic principles. Postoperative survival for IBD-related CRC is good, and diligent surveillance and follow-up are critical to the patient's overall prognosis.

Deregulation of Cyclin E induces chromosomal instability in human colon cancer

AIM: To study the influence of stably inducible expression of Cyclin E on the chromosomal instability in human colon cancer cell line DLD1.

METHODS: Tetracycline-responsive gene-inducible cell line DLD1tTA-cyclin E was generated. Western blot was used to examine the induction of Cyclin E expression upon removal of doxycycline. 4'-6-Diamidino-2-phenylindole (DAPI) staining was performed to detect the percentage of cells with chromosomal instability 1, 3, 5, 7 and 14 d after the induction of Cyclin E expression.

RESULTS: Western blot showed that the peak of Cyclin E expression appeared 96 h after induction. The percentage of cells with chromosomal instability in tet-off DLD1tTA-Cyclin E cells ranged from 0.97% to 1.22% (t = 3.81, P > 0.01). However, the percentages of cells with chromosomal instability were 2.41%, 3.63%, 3.92%, 6.17% and 8.34%, respectively, 1, 3, 5, 7 and 14 d after the induction of Cyclin E expression (t = 4.77, P < 0.01).

CONCLUSION: Deregulation of cyclin E can induce the formation of aneuploidy in human colon cancer cell line DLD1, and it also plays an important role in the pathway of chromosomal instability.