Surgical management of colon cancer

Prognostic analysis and comparison of colon cancer in Han and Hui patients

AIM

To investigate the relevant prognostic factors and their differences between colorectal cancer (CRC) patients of Chinese Han and Hui ethnicities in the Beijing region.

METHODS

A retrospective analysis of 880 patients diagnosed with CRC at Xuanwu Hospital, Capital Medical University between September 2001 and September 2011 was performed. Among the 880 patients, 398 and 482 were Hui and Han, respectively. Characteristics including sex, age, diet, tumor size, primary tumor site, Dukes' stage and degree of differentiation were analyzed for their influence on prognosis. Data on dietary structures were recorded through a questionnaire survey conducted during the patient's first visit, return visit or follow-up checkups.

RESULTS

Among patients with colon cancer, the 5-year survival rate for patients of Hui ethnicity was lower than that for Han patients (P = 0.025). Six risk factors (age of onset, dietary structure, tumor size, Dukes' stage, location of cancer and degree of differentiation) in both Han and Hui patients were identified as prognostic factors (P < 0.05). Multivariate analysis showed that age of onset (P = 0.002), diet (P = 0.000), Dukes' stage (P = 0.000) and degree of differentiation (P = 0.000) are prognostic factors affecting both ethnic groups. Comparison of prognostic factors between Han and Hui patients with CRC showed that dietary structure was a statistically significant factor, and diet varied significantly between the two ethnic groups.

CONCLUSION

Dietary structure has a significant influence on colon cancer prognosis among Han and Hui patients with colon cancer in Beijing, which may cause a difference in their survival rates.

An effective vaccine against colon cancer in mice: Use of recombinant adenovirus interleukin-12 transduced dendritic cells

AIM: To investigate the effect of a vaccine with recombinant adenovirus interleukin-12 (AdVIL-12) transduced dendritic cells (DCs) against colon cancer in mice.

METHODS: DCs and AdVIL-12 were incubated together at different time intervals and at different doses. Supernatant was collected and tested for IL-12 by enzyme-linked immunosorbent assay (ELISA). In order to determine whether tumor cell lysate-pulsed (TP) AdVIL-12/DCs enhance therapeutic potential in the established tumor model, CT26 colon tumor cells were implanted subcutaneously (s.c.) in the midflank of naïve BALB/c mice. Tumor-bearing mice were injected with a vaccination of CT26 TP AdVIL-12/DCs on d 3 and 10. As a protective colon tumor model, naïve BALB/c mice were immunized s.c. in their abdomens with CT26 TP AdVIL-12/DCs twice at seven day intervals. After the immunization on d 7, the mice were challenged with a lethal dose of CT26 tumor cells and survival times were evaluated. Subsequently, cytotoxic T lymphocyte (CTL) activity and interferon gamma (IFNγ) secretion was evaluated in the immunized mice, and assayed CTL ex vivo.

RESULTS: Murine DCs were retrovirally transduced with AdVIL-12 efficiency, and the AdVIL-12 transduced DCs secreted a high level of IL-12 (AdVIL-12/DCs, 615.27 ± 42.3 pg/mL vs DCs, 46.32 ± 7.29 pg/mL, P < 0.05). Vaccination with CT26 TP AdVIL-12/DCs could enhance anti-tumor immunity against CT26 colon tumor in murine therapeutic models (tumor volume on d 19: CT26 TP AdVIL-12/DCs 107 ± 42 mm³vs CT26 TP DCs 383 ± 65 mm³, P < 0.05) and protective models. Moreover, the CT26 TP AdVIL-12/DC vaccination enhances tumor-specific CTL activity, producing high levels of IFNγ in immunized mice. Ex vivo primed T cells with AdVIL-12/DCs were able to induce more effective CTL activity than in primed T cells with CT26 TP/DCs (E:T = 100:1, 69.49% ± 6.11% specific lysis vs 37.44% ± 4.32% specific lysis, P < 0.05).

CONCLUSION: Vaccination with recombinant AdVIL-12 transduced DC pulsed tumor cell lysate enhance anti-tumor immunity specific to colon cancer in mice.