Staging and prognosis of colon cancer

Anesthetic propofol inhibits ferroptosis and aggravates distant cancer metastasis via Nrf2 upregulation

The impact of anesthetic management on the prognosis of patients with cancer undergoing surgery is controversial. Circulating tumor cells (CTCs) play critical roles during cancer metastasis and can be released in large quantities during surgery. The ferroptosis of CTCs is related to metastasis. Whether anesthetics affect distant metastasis by increasing the survival of CTCs is unknown. To test this hypothesis, mice were inoculated with cancer cells via tail vein injection before treatment with propofol or sevoflurane for 2 h. After 2 weeks, more metastases were observed in the propofol group compared with the sevoflurane and vehicle groups. Then, we used the ferroptosis inhibitor ferrostatin-1 to explore the effect of ferroptosis on metastasis. Similar to propofol, pretreatment with ferrostatin-1 significantly increased CTC survival in mouse lungs at 24 h and the tumor burden at 10 weeks post-inoculation. Moreover, propofol protected cancer cells from RSL3-induced ferroptosis in vitro, as evidenced by decreases in intracellular levels of reactive oxygen species (ROS), lipid peroxide, and ferroptosis markers. Further studies showed that propofol treatment upregulated the expression of nuclear factor erythroid 2-related factor 2 (Nrf2) and its downstream target genes, including HO-1, NQO1, and SLC7A11. Finally, the targeted knockdown of Nrf2 abolished the anti-ferroptosis effect of propofol. Collectively, we demonstrated the risk of a specific type of anesthetic, propofol, in promoting cancer cell metastasis through Nrf2-mediated ferroptosis inhibition. These findings may guide the choice of anesthetic for surgical removal of tumors.

Development of necroptosis-related gene signature to predict the prognosis of colon adenocarcinoma

Colon adenocarcinoma (COAD) is a common malignancy and has a high mortality rate. However, the current tumor node metastasis (TNM) staging system is inadequate for prognostic assessment of COAD patients. Therefore, there is an urgent need to identify reliable biomarkers for the prognosis COAD patients. The aberrant expression of necroptosis-related genes (NRGs) is reported to be associated with tumorigenesis and metastasis. In the present work, we compared the expression profiles of NRGs between COAD patients and normal individuals. Based on seven differentially expressed NRGs, a risk score was defined to predict the prognosis of COAD patients. The validation results from both training and independent external cohorts demonstrated that the risk score is able to distinguish the high and low risk COAD patients with higher accuracies, and is independent of the other clinical factors. To facilitate its clinical use, by integrating the proposed risk score, a nomogram was built to predict the risk of individual COAD patients. The C-index of the nomogram is 0.75, indicating the reliability of the nomogram in predicting survival rates. Furthermore, two candidate drugs, namely dapsone and xanthohumol, were screed out and validated by molecular docking, which hold the potential for the treatment of COAD. These results will provide novel clues for the diagnosis and treatment of COAD.

Functionalized LbL Film for Localized Delivery of STAT3 siRNA and Oxaliplatin Combination to Treat Colon Cancer

The aim of the study was to develop and evaluate the efficacy of a functionalized layer-by-layer (LbL) assembled film entrapped with oxaliplatin (OX) and signal transducer and activator of transcription 3 (STAT3) siRNA in the localized treatment of colon cancer. The LbL film was prepared by the sequential layering of chitosan (CS) and alginate to attain desired physical and mechanical properties. The film was functionalized by coating folic acid-conjugated CS on one side. On the other side, polycaprolactone was coated as a backing layer to provide directional drug release. OX was entrapped within the layers of the film, while STAT3 siRNA was complexed with CS to form nanoparticles before entrapment in the LbL film. The CS-siRNA nanoparticles were taken up by the colon carcinoma, Caco-2 cells within 3 h and provided concentration-dependent reduction in STAT3 protein expression. The functionalized LbL film (F-LbL film) selectively adhered to the colon cancer tissue in the mice model, whereas the nonfunctionalized film adhered to the normal colon tissue. The combination of OX and STAT3 siRNA provided significantly greater tumor regression, survival rate, and STAT3 protein suppression after localized delivery through oral administration compared with intravenous administration. Taken together, the F-LbL film can selectively bind to colon tumors for localized delivery of drugs to treat colon cancer.

An Apoptosis-Related Gene Prognostic Index for Colon Cancer

Purpose: To construct an apoptosis-related gene prognostic index (ARGPI) for colon cancer, and clarify the molecular and immune characteristics of the risk subgroup as defined by the prognostic index and the benefits of adjuvant chemotherapy. Integrating the prognostic index and clinicopathological risk factors to better evaluate the prognosis of patients with colon cancer. Methods: Based on the colon adenocarcinoma data in the TCGA database, 20 apoptosis-related hub genes were screened by weighted gene co-expression network analysis (WGCNA). Five genes constituting the prognosis model were determined by Cox regression and verified by the Gene Expression Omnibus (GEO) dataset. Then the molecular and immune characteristics of risk subgroups defined by the prognostic index and the benefits of adjuvant chemotherapy were analyzed. Finally, nomograms integrating ARGPI and four clinicopathological risk factors were used to evaluate the prognosis of patients with colon cancer. Results: The ARGPI was constructed based on the FAS, VWA5A, SPTBN2, PCK1, and TIMP1 genes. In the TCGA cohort, patients in the low-risk subgroup had a longer progression-free interval (PFI) than patients in the high-risk subgroup, which coincided with the results of the GEO cohort. The comprehensive results showed that the high-risk score was related to the enrichment of the cell cycle pathway, high mutation rate of TP53 and KRAS, high infiltration of T regulatory cells (Tregs), immunosuppressive state, and less chemotherapeutic benefit. However, low-risk scores are related to drug metabolism-related pathways, low TP53 and KRAS mutation rates, high infiltration of plasma cells, more resting CD4 memory cells and eosinophils, active immune function, and better chemotherapeutic benefits. Receiver operating characteristic curve of two-year progress prediction evaluation showed that the ARGPI had higher prognostic accuracy than TNM staging. Nomograms integrating ARGPI and clinicopathological risk factors can better evaluate the prognosis of patients with colon cancer. Conclusions: The ARGPI is a promising biomarker for determining risk of colon cancer progression, molecular and immune characteristics, and chemotherapeutic benefit. This is a reliable method to predict the prognosis of colon cancer patients. It also can assist doctors in formulating more effective treatment strategies.

Log Odds of Positive Lymph Node- (LODDS-) Based Competing-Risk Nomogram for Predicting Prognosis of Resected Rectal Cancer: A Development and Validation Study

Background and Aims. Cancer-specific survival (CSS) of rectal cancer (RC) is associated with several factors. We aimed to build an efficient competing-risk nomogram based on log odds of positive lymph nodes (LODDS) to predict RC survival. Methods. Medical records of 8754 patients were collected from the Surveillance, Epidemiology, and End Results (SEER) database, of 4895 patients from SEER during 2011–2014 and of 478 patients from an Eastern center as a development cohort, validation cohort, and test cohort, respectively. Univariate and multivariate competing-risk analyses were performed to build competing-risk nomogram for predicting the CSS of RC patients. Prediction efficacy was evaluated and compared with reference to the 8th TNM classification using the factor areas under the receiver operating characteristic curve (AUC) and Brier score. Results. The competing-risk nomogram was based on 6 variables: size, M stage, LODDS, T stage, grade, and age. The competing-risk nomogram showed a higher AUC value in predicting the 5-year death rate due to RC than the 8th TNM stage in the development cohort (0.81 vs. 0.76), validation cohort (0.85 vs. 0.82), and test cohort (0.71 vs. 0.66). The competing-risk nomogram also showed a higher Brier score in predicting the 5-year death rate due to RC than the 8th TNM stage in the development cohort (0.120 vs. 0.127), validation cohort (0.123 vs. 0.128), and test cohort (0.202 vs. 0.226). Conclusion. We developed and validated a competing-risk nomogram for RC death, which could provide the probability of survival averting competing risk to facilitate clinical decision-making.

Low circulating 25-hydroxyvitamin D level is associated with increased colorectal cancer mortality: a systematic review and dose-response meta-analysis

Epidemiological studies have suggested inconclusive associations between 25-hydroxyvitamin D (25(OH)D) and survival in patients with colorectal cancer (CRC). The aim of the present study was to quantitatively assess these associations. PubMed, EMBASE, and Web of Science databases were systematically searched for eligible studies. Subgroup analyses based on study geographic location, publication year, length of follow-up time, sample size, and stage were conducted to explore the potential sources of heterogeneity. Dose-response relationships and pooled hazard ratios (HR) for overall and CRC-specific survival comparing the highest versus the lowest categories of circulating 25(OH)D concentrations were assessed. Overall, 17 original studies with a total of 17,770 CRC patients were included. Pooled HR (95% confidence intervals) comparing highest versus lowest categories were 0.64 (0.55-0.72) and 0.65 (0.56-0.73) for overall and CRC-specific survival, respectively. Studies conducted in the U.S.A., with median follow-up time ≥ 8 years, larger sample size, and including stage I-III patients showed a more prominent association between 25(OH)D concentrations and overall survival. The dose-response analysis showed that the risk of all-cause mortality was reduced by 7% (HR = 0.93; 95% CI: 0.90, 0.95), and the risk of CRC-specific mortality was reduced by 12% (HR = 0.88; 95% CI: 0.84, 0.93) for each 20 nmol/l increment of 25(OH)D concentration. This meta-analysis provides evidences that a higher 25(OH)D concentration is associated with lower overall mortality and CRC-specific mortality.

Omics Integration Analyses Reveal the Early Evolution of Malignancy in Breast Cancer

The majority of cancer evolution studies involve individual-based approaches that neglect the population dynamics necessary to build a global picture of cancer evolution for each cancer type. Here, we conducted a population-based study in breast cancer to understand the timing of malignancy evolution and its correlation to the genetic evolution of pathological stages. In an omics integrative approach, we integrated gene expression and genomic aberration data for pre-invasive (ductal carcinoma in situ; DCIS, early-stage) and post-invasive (invasive ductal carcinoma; IDC, late-stage) samples and investigated the evolutionary role of further genetic changes in later stages compared to the early ones. We found that single gene alterations (SGAs) and copy-number alterations (CNAs) work together in forward and backward evolution manners to fine-tune the signaling pathways operating in tumors. Analyses of the integrated point mutation and gene expression data showed that (i) our proposed fine-tuning concept is also applicable to metastasis, and (ii) metastases sometimes diverge from the primary tumor at the DCIS stage. Our results indicated that the malignant potency of breast tumors is constant over the pre- and post-invasive pathological stages. Indeed, further genetic alterations in later stages do not establish de novo malignancy routes; however, they serve to fine-tune antecedent signaling pathways.

Significance of Tumor-Infiltrating Immune Cells in the Prognosis of Colon Cancer

Objective

Increasing evidence has indicated an association between immune infiltration in colon cancer and clinical outcomes. The aim of this research is to comprehensively investigate the effect of 22 tumor-infiltrating immune cells (TIICs) on the prognosis of colon cancer patients.

Methods

In our research, CIBERSORT algorithm was used to calculate the proportion of 22 TIICs in 369 colon cancer cases and 39 normal cases from the TCGA cohort. Cox regression analysis was used to analyze the effect of 22 TIICs on the prognosis of colon cancer. Immune risk scoring model was constructed based on the statistical correlation between TIICs subpopulation and survival. Meanwhile, multivariate Cox regression analysis was utilized to investigate whether the immune risk score model was an independent factor for predicting the prognosis of colon cancer. Nomogram was constructed to comprehensively predict the survival rate of colon cancer. P< 0.05 was considered to be statistically significant.

Results

The results of the difference analysis showed that except for 12 TIICs, the remaining immune cells exhibited no differential infiltration between normal and colon cancer tissues (p<0. 05). Univariate Cox regression analysis revealed 5 immune cells statistically correlated with colon cancer-related survival risk, including B cells naive, B cells memory, monocytes, macrophages M0, macrophages M1 (P<0.05). In addition, a four-cell based immune risk scoring model was constructed through LASSO Cox regression analysis. KM curve indicated that patients in highrisk were associated with poor outcomes (p<0.001). ROC curve indicated that the immune risk score model was reliable in predicting survival risk (AUC=0.848). Our model showed satisfying AUC and survival correlation in the validation dataset (3-year over survival (OS) AUC=0.941, 5-year OS AUC=0.865, P=0.022). Furthermore, multivariate Cox regression analysis confirmed that the immune risk score model was an independent factor for predicting the prognosis of colon cancer (hazard ratio (HR) =5.017, 95% confidence interval (CI) =2.336–10.777; P<0.001). Ultimately, a nomogram was established to comprehensively predict the survival of colon cancer patients with the results of multivariate Cox regression analysis.

Conclusion

Collectively, tumor-infiltrating immune cells played an essential role in the prognosis of colon cancer. Furthermore, immune risk score was an independent predictive factor of colon cancer, indicating a poor survival.

Association of Circulating 25-Hydroxyvitamin D Levels with Colorectal Cancer: An Updated Meta-Analysis

A higher serum 25-hydroxyvitamin D (25(OH)D) concentration benefits colorectal cancer prevention. However, whether it can improve the prognosis among patients is still under discussion. This study aims to explore the impacts of high level 25(OH)D on the survival of colorectal cancer patients. PubMed, Embase, and Cochrane were searched from January 2000 to August 2017 for relevant articles. Only published studies focusing on the relationship between 25(OH)D levels at or near the time of diagnosis and survival were considered. Two review authors independently assessed the risk of bias for each study, and any disagreement was resolved by discussion or by involving a third assessor. Eleven studies comprising 7,367 patients were included. In these studies, there were considerable differences between the higher 25(OH)D level group and the lower group in terms of overall survival (OS), progression-free survival (PFS) and colorectal cancer-specific survival (CSS) in a random effect model (OS: HR 0.67, 95% CI 0.56-0.80, p<0.00001; CSS: HR 0.73, 95% CI 0.55-0.97, p=0.03; PFS: HR 0.74, 95% CI 0.61-0.90, p=0.003). Moreover, the combined hazard ratios of OS and CSS had considerably significant heterogeneity which may be explained by subgroup analysis. The relationship between 25(OH)D and tumor characteristics/lifestyle factors was also included in the meta-analysis. BMI (p=0.03), smoking (p=0.03) and physical activity (p=0.002) seemed to be associated with circulating 25(OH)D level. Publication bias was undetected. Colorectal cancer patients with higher circulating 25(OH)D level may have a better prognosis.

Comparison of Different Lymph Node Staging Systems in Patients With Resectable Colorectal Cancer

Background and Objectives: Currently, the United States Joint Commission on Cancer (AJCC) N staging, lymph node positive rate (LNR), and log odds of positive lymph nodes (LODDS) are the main lymph node (LN) staging systems. However, the type of LN staging system that is more accurate in terms of prognostic performance remains controversial. We compared the prognostic accuracy of the three staging systems in patients with CRC and determine the best choice for clinical applications. Methods: From the Surveillance, Epidemiology, and End Results (SEER) database, 56,747 patients were identified who were diagnosed with CRC between 2004 and 2013. Akaike's Information Criterion (AIC) and Harrell's Consistency Index (c-index) were used to assess the relative discriminative abilities of different LN staging systems. Results: In 56,747 patients, when using classification cut-off values for evaluation, the LNR of Rosenberg et al. showed significantly better predictive power, especially when the number of dissected lymph nodes (NDLN) were insufficient. When analyzed as a continuous variable, the LODDS staging system performed the best and was not affected by the NDLN. Conclusions: We suggest that the LNR of Rosenberg et al. should be introduced into the AJCC system as a supplement when the NDLN is insufficient until the optimal LODDS cut-off values are calculated.

Impact of protamine I on colon cancer proliferation, invasion, migration, diagnosis and prognosis

This paper investigates protamine I (PRM1) expression and its effects on proliferation, invasion and migration of colon cancer cells as well as its function in clinical diagnosis and prognosis. Gene chips were used to screen differentially expressed genes. PRM1 expression was detected by Western blotting and quantitative real time-polymerase chain reaction (qRT-PCR). Hematoxylin and eosin (HE) staining and immunohistochemistry were utilized to compare the expression of PRM1 from multiple differentiation levels of colon cancer tissues. Cell viability, cell apoptosis and cell cycle were tested using the MTT assay and flow cytometry. Cell invasion and migration capability were tested using the Transwell assay and wound healing. In vivo effects of PRM1 on colon cancer were explored using a xenograft model. PRM1 expression in serum was detected by enzyme-linked immunosorbent assay (ELISA). The expression level of PRM1 was significantly higher in colon cancer tissues and the staining degree of PRM1 in poorly-differentiated was stronger. pcDNA3.1-PRM1 decreased cell apoptosis while it increased the proliferation, cell invasion and migration. The si-PRM1 group displayed an opposite tendency. The serum PRM1 level was significantly higher and could serve as a diagnostic biomarker for colon cancer.

Prognostic and clinical significance of claudin-1 in colorectal cancer: A systemic review and meta-analysis

BACKGROUND

The current reports on the association of claudin-1 expression with colorectal cancer (CRC) result were controversial. Thus, we conducted a meta-analysis to assess the correlation between claudin-1 expression and the clinical parameters and assess the prognostic value of claudin-1 in CRC.

METHODS

Systematic searches on PubMed, Embase, Elsevier, CNKI (China National Knowledge Infrastructure), Wanfang data and Cochrane Library prior to August 2016 were performed. The pooled odds ratio (OR) with its 95% confidence interval (95 %CI) was used to assess association between claudin-1 expression and clinical parameters of CRC patients, and to assess association between claudin-1 expression and the prognostic value of CRC patients.

RESULTS

Eight studies with a total of 1146 CRC patients were included. Overall, the pooled results showed that low expression of claudin-1 was associated with TNM III-IV stage of CRC patients (OR: 1.714, 95%CI: 1.215-2.418, P = 0.002). Low expression of claudin-1 was also associated with a poor survival in CRC patients (one year survival rate: OR: 2.112, 95%CI: 1.028-4.339, P = 0.042; three years survival rate: OR: 1.501, 95%CI: 1.030-2.186, P = 0.035; five years survival rate: OR: 1.794, 95%CI: 1.139-2.439, P = 0.000). Whereas, low expression of claudin-1 is not associated with gender (OR: 1.259, 95%CI: 0.957-1.657, P = 0.100), tumors' differentiation (OR: 1.317, 95%CI: 0.916-1.892, P = 0.137), depth of invasion (OR: 1.016, 95 %CI: 0.701-1.472, P = 0.935) and lymph node metastasis group (OR: 1.286, 95% CI: 0.982-1.684, P = 0.06) of CRC.

CONCLUSIONS

Low expression of claudin-1 is associated with TNM III-IV stage and poor prognosis of CRC patients. Low expression of claudin-1 is not associated with gender, tumors' differentiation depth of invasion and lymph node involvement of CRC patients.

The influence of neoadjuvant therapy for the prognosis in patients with rectal carcinoma: a retrospective study

Rectal cancer, defined as a cancerous lesion of the colon distal to the rectosigmoid junction, is the fourth most common cancer cause of death globally. There were 474 patients with rectal cancer who underwent surgery between October 2007 and May 2013 enrolled in our center. Patients were respectively categorized by neoadjuvant therapy. This study aimed to explore the predictive factors that affected the Progression-free survival and overall survival of the patients with rectal cancer. Clinical characteristics of patients were compared with the groups and potential prognostic factors were analyzed by SPSS 19.0. In our study, neoadjuvant therapy increased the anus-retained rate (64.4 vs 53.4 % P = 0.016) and remission rate in the treatment group, compared to the non-treatment group (62.6 vs 34.8 %; P = 0.000). The neoadjuvant concurrent chemoradiotherapy, more operative duration, anus retained and micturition damaged are positive prognostic factors of PFS to patients. Poor differentiation, the tumor of ulcer, invasive, and pT4 stage, contributed the poor factors for PFS of patients (P < 0.05). Additionally, the patients with neoadjuvant concurrent chemoradiotherapy and adjuvant chemotherapy underwent the better prognosis of OS. Adjuvant chemotherapy cannot increase PFS of the patients who accepted neoadjuvant therapy after surgery get pCR, but can improve OS. The anus-retained and neoadjuvant radiotherapy, duration of surgery in rectal cancer have the positive correlation. Micturition damaged and neoadjuvant radiotherapy were positively correlated as well. In conclusion, adjuvant chemotherapy does not improve the PFS of patients with pCR to neoadjuvant therapy, but is good for OS. Further prospective and large population-based clinical studies are needed to establish clinical guidelines for the use of neoadjuvant therapy and adjuvant chemotherapy in patients with rectal cancer.

A population-based study elicits a reverse correlation between age and overall survival in elderly patients with rectal carcinoma receiving adjuvant chemotherapy

Colorectal cancer is the third most common cancer and the fourth most common cause of cancer-related death globally. This population-based study aimed to explore the predictive factors that affected the overall survival of rectal cancer patients receiving adjuvant chemotherapy plus radical surgery using a Cox proportional hazards modeling approach. A total of 619 patients with rectal cancer who underwent surgery were enrolled between October 2006 and May 2013. Clinical characteristics of the patients were compared among the groups and potential prognostic factors were analyzed using the spss program, version 19.0. Patients aged ≥ 70 years have distinctive characteristics such as lager tumour size (≥ 5 cm), damaged micturition and higher incidence of diabetes compared to younger and middle-aged patients. Male gender, tumour size (≥ 5 cm), poor differentiation, later stage, adjuvant chemotherapy, damaged micturition, hypertension or diabetes are associated with a worse prognosis for rectal cancer patients (P < 0.05). However, smoking is a favourable factor to the patients (P = 0.018). Age of ≥ 70 years is an independent prognostic factor for patients with rectal cancer after surgery (P = 0.000) and elderly patients with Stage II and III disease receiving adjuvant chemotherapy show a favourable prognosis. The elderly patients who suffered from diabetes receiving adjuvant chemotherapy have a poor prognosis. Further prospective and large population studies are warranted to confirm the findings of this study.

Aberrant MEK5/ERK5 signalling contributes to human colon cancer progression via NF-κB activation

This study was designed to evaluate MEK5 and ERK5 expression in colon cancer progression and to ascertain the relevance of MEK5/ERK5 signalling in colon cancer. Expression of MEK5 and ERK5 was evaluated in 323 human colon cancer samples. To evaluate the role of MEK5/ERK5 signalling in colon cancer, we developed a stable cell line model with differential MEK5/ERK5 activation. Impact of differential MEK5/ERK5 signalling was evaluated on cell cycle progression by flow cytometry and cell migration was evaluated by wound healing and transwell migration assays. Finally, we used an orthotopic xenograft mouse model of colon cancer to assess tumour growth and progression. Our results demonstrated that MEK5 and ERK5 are overexpressed in human adenomas (P<0.01) and adenocarcinomas (P<0.05), where increased ERK5 expression correlated with the acquisition of more invasive and metastatic potential (P<0.05). Interestingly, we observed a significant correlation between ERK5 expression and NF-κB activation in human adenocarcinomas (P<0.001). We also showed that ERK5 overactivation significantly accelerated cell cycle progression (P<0.05) and increased cell migration (P<0.01). Furthermore, cells with overactivated ERK5 displayed increased NF-κB nuclear translocation and transcriptional activity (P<0.05), together with increased expression of the mesenchymal marker vimentin (P<0.05). We further demonstrated that increased NF-κB activation was associated with increased IκB phosphorylation and degradation (P<0.05). Finally, in the mouse model, lymph node metastasis was exclusively seen in orthotopically implanted tumours with overactivated MEK5/ERK5, and not in tumours with inhibited MEK5/ERK5. Our results suggested that MEK5/ERK5/NF-κB signalling pathway is important for tumour onset, progression and metastasis, possibly representing a novel relevant therapeutic target in colon cancer treatment.

Major postoperative complications following elective resection for colorectal cancer decrease long-term survival but not the time to recurrence

AIM

The aim of the study was to determine the effect of major complications after colorectal cancer surgery on survival and time to recurrence.

METHOD

Patients having a curative colorectal cancer resection and a follow-up of at least 3 years were identified from a prospective database. Major complications were defined as Clavien-Dindo Grades 3b or 4 and their impact on time to recurrence and mortality was analysed by univariate and multivariable analysis. Postoperative death within 30 days or during the initial hospitalization (Clavien-Dindo Grade 5) was a priori excluded.

RESULTS

From 2003 to 2012, 868 colorectal cancer resections resulting in 63 (7%) major postoperative complications including deaths (Clavien-Dindo ≥ 3b) were identified. After exclusion of Grade 5 complications (postoperative or in-hospital deaths), 844 resections with 39 (5%) major complications remained for analysis. Median follow-up time was 5.7 years. Using the Kaplan-Meier method, the estimated crude 5-year overall survival probability was 78% (95% CI 75-81) in the group without and 65% (95% CI 51-83) in the group with major complications (P = 0.009, log-rank test). Major complications were a significant negative predictor for overall survival (hazard ratio 2.42, 95% CI 1.41-4.14) when adjusted for sex, age, American Society of Anesthesiologists grade, tumour site (colon vs rectum), R stage and tumour stage. However, in both univariate and multivariable analysis, major complications were not a significant predictor for time to recurrence (hazard ratio 1.29, 95% CI 0.56-2.99).

CONCLUSION

Non-lethal major postoperative complications seem to have a negative long-term impact on survival but not on time to recurrence.

Assessment of prognostic factors after primary tumor resection in metastatic colon cancer patients: a Veteran's Affairs Central Cancer Registry (VACCR) analysis, 1995-2008

BACKGROUND

Resection of the primary tumor in metastatic colon cancer may occur for palliation of bleeding or obstruction despite distant metastases. This study evaluates clinicopathologic features that serve as prognostic markers in those patients with stage IV colon cancer who undergo resection of their primary tumor.

METHODS

Retrospective analysis of stage IV colon cancer patients who underwent surgical resection of the primary tumor from 1995 to 2008 was done via the Veteran's Affairs Central Cancer Registry. Age, Charlson co-morbidity index score, extent of metastases, sex, number of lymph nodes examined, lymph node ratio (LNR), type of surgery, use of adjuvant chemotherapy, primary tumor site, and grade were studied with respect to overall survival by using log-rank and Kaplan-Meier analysis.

RESULTS

There were 2,625 patients with stage IV colon cancer who had primary tumor resection. Age at diagnosis, Charlson co-morbidity index score, lymph node ratio, and use of chemotherapy were found to be independent predictors of survival by multivariate analysis.

CONCLUSION

Clinicopathologic factors such as LNR, use of chemotherapy, age, co-morbidities, site of primary colon tumor, and number of sites of metastasis are all independent predictors of overall survival in patients who undergo primary colon tumor resection in the metastatic setting.

Predictive value of immunohistochemical expression of claudin-1 in colonic carcinoma

OBJECTIVE

Colonic carcinoma is one of the most common cancers worldwide. Recently, the possible involvement of claudin-1, one of the major tight junction proteins, in the process of tumorigenesis has been suggested. Also, claudin-1 has emerged as a potential prognostic factor in different types of tumors. The aim of this study was to detect caludin-1 expression in colonic carcinoma and to correlate its expression with clinicopathological variables in an attempt to delineate its role as a potential new prognostic marker.

MATERIAL AND METHODS

Immunohistochemical expression of claudin-1 was assessed in 50 Egyptian patients with colonic adenocarcinoma. The predictive performance of claudin-1 expression was statistically evaluated.

RESULTS

Decreased claudin-1 expression was found in 62% of colonic adenocarcinoma cases while similar expression was found in 38% of the cases. Statistical analysis showed a statistically significant inverse correlation between claudin-1 expression and tumor grade, depth of invasion, lymph node involvement, and tumor stage. Regression analysis showed that claudin-1 decreased expression significantly predicts that the tumor is of a high grade, high stage, and is associated with lymph node involvement. ROC curve analysis showed that claudin-1 had a sensitivity of 88.24% and a specificity of 81.25% for the prediction of tumor stage and a sensitivity of 73.33% and a specificity of 82.86% for the prediction of lymph node involvement.

CONCLUSIONS

Claudin-1 decreased expression in colonic carcinoma contributes to tumor dedifferentiation, invasion and metastasis. Claudin-1 expression could be used as a predictor of colonic carcinoma stage and lymph node status with a high sensitivity and specificity.

A study of aspects on gender and prognosis in synchronous colorectal cancer

AIM

To assess differences in demography, pathology and prognosis with tumor multiplicity in colorectal cancer.

METHOD

A retrospective single centre study of all patients surgically treated for a colorectal cancer during 1999-2008 (n = 2524). Patient characteristics, pathology and follow-up data were retrieved. Survival was assessed by overall and cancer specific survival.

RESULTS

60 (2.4%) patients had a synchronous cancer (SC), associated with right colon, higher age, more assessed lymph nodes but a lower frequency of stage III/IV disease (42% vs. 52%). There was no overall prognostic difference between single or multiple cancer patients but females with SC had better survival than corresponding males (P < 0.046).

CONCLUSION

The incidence of synchronous cancers was 2.4% with the second cancer often located in right colon. The SC patients were older than single tumor patients, had a lower frequency of stage III/IV disease and the females with SC had a better survival prognosis than corresponding males.

Sentinel lymph node in colorectal cancer — 5 years follow up

To assess the impact of micrometastases in sentinel and non-sentinel lymph nodes on long-term survival rates of patients treated for colorectal cancer (CRC). Data of 57 patients diagnosed with CRC and treated in the Department of Surgical Oncology in Gdansk in the years 2002–2006 were retrospectively analyzed. Clinico-histopathological data were analyzed using chi-square tests. The effect on long-time survival rates was analyzed using Kaplan-Meier survival probability estimates. Identification of the SLN was performed using the blue dye staining method. All regional lymph nodes were subject to standard histopathological examination. Additionally in 32(56.14%) patients whose nodes were found negative for metastases on standard staining further immunohistochemical analyses were performed. In the analyzed group SLNB was performed in 42(73.7%) patients with colon cancer and in 15(26.3%) with rectal cancer. Identification of the SLN was possible in 45(78.9%) patients. The sensitivity of SLNB was 33%. False negatives were found in 66%. SLNB is a feasible method in CRC patients. We presume that lack of micrometastases in the SLN and non-SLN cannot be regarded as a prognostic factor.

Can lymph node ratio take the place of pN categories in the UICC/AJCC TNM classification system for colorectal cancer?

BACKGROUND

Lymph node ratio (LNR) has been reported to represent a powerful independent prognostic value in some malignancies. The significance of LNR in colorectal cancer is still under debate.

METHODS

A total of 505 patients with stage III colorectal cancer were reviewed. Using running log-rank statistics, we calculated the best cutoff values for LNRs and proposed a novel rN category: rN1, 0% < LNR ≤ 35%; rN2, 35% < LNR ≤ 69%; and rN3, LNR > 69%. A Spearman's correlation coefficient test was used to assess the correlation between the number of retrieved nodes and the number of metastatic nodes, as well as the number of retrieved nodes and the LNRs. Univariate and two-step multivariate analyses were performed, respectively, to identify the significant prognostic clinicopathologic factors.

RESULTS

The 5-year overall survival rate decreased significantly with increasing LNRs: rN(1) = 61% survival rate, rN(2) = 30.3% survival rate, and rN(3) = 11.2% survival rate (P < 0.001). Univariate and two-step multivariate analyses identified the rN category as a significant prognostic factor no matter whether the minimum number of LNs retrieved was met. There was a significant prognostic difference among different rN categories for any pN category, but no apparent prognostic difference was seen between different pN categories in any rN category. Moreover, marked heterogeneity could be seen within III(a-c) substages when survival was compared among rN(1-3) categories but not between pN(1-2) categories.

CONCLUSIONS

rN categories have more potential for predicting patient outcomes and are superior to the UICC/AJCC pN categories. We recommend rN categories for prognostic assessment and rN categories should be reported routinely in histopathological reports.

Colonoscopy and computerized tomography scan are not sufficient to localize right-sided colonic lesions accurately

AIM

Accurate preoperative localization of colonic lesions is critical especially in laparoscopic colectomy where tactile localization is absent particularly in screen-detected tumours. The study aimed to evaluate the accuracy of colonoscopy and double-contrast computerized tomography (CT) scan to localize lesions treated by right hemicolectomy.

METHOD

A retrospective chart review was performed of patients treated by right hemicolectomy under the colorectal service between July 2003 and October 2006. Preoperative tumour location determined by CT scan and colonoscopy was compared with the intra-operative and histopathological findings.

RESULTS

Out of 101 patients, 73 (73%) were for adenoma or cancer, with a final diagnosis of adenocarcinoma in 59 (58%). Preoperative localization was inaccurate in 29% of lesions using both CT and colonoscopy. In the transverse colon, colonoscopy alone was only 37.5% accurate, increasing to 62.5% when information from the CT scan was added.

CONCLUSION

Preoperative localization of right-sided colon cancers using colonoscopy and CT scanning is unreliable in at least 29% of cases. Inaccurate localization of transverse colon tumours risks inadequate lymphadenectomy with an adverse cancer outcome. Preoperative abdominal CT scan improves accuracy but endoscopic tattoo localization should be employed routinely especially in patients undergoing laparoscopic resection.

Tumour differentiation grade is associated with TNM staging and the risk of node metastasis in colorectal cancer

AIM

The tumour differentiation grade has been shown by numerous multivariate analyses to be a stage-independent prognostic factor in colorectal cancer. The aim of this study was to explore the importance of differentiation grading for the staging of colorectal cancer and how it relates to the components of the TNM system.

MATERIAL AND METHODS

The study was a retrospective single-centre analysis of all patients undergoing surgical resection for colorectal cancer during the period 2002-2007 (n = 1239). The clinical parameters and pathology data of overall stage, differentiation grade, local tumour (T)-stage and metastasis status (M-stage) were included as well as the lymph node count of both assessed and metastatic nodes. The differentiation grade was correlated with demography, overall stage and each component of the TNM staging system. The correlation between differentiation grade and N-stage was also explored for the separate T-stages.

RESULTS

The tumour differentiation grade correlated significantly with the overall TNM stage (p < 0.0001). The grade significantly correlated with the T-stage and the risk of having lymph node metastasis (p < 0.0001). A high grade was associated with a higher positive lymph node count in stage III disease (p < 0.0002). For the T-stages, the risk of node metastasis was significantly linked to the tumour grade. A low grade (G1) T2 had a 17% risk of lymph node metastasis compared to a 44% risk for a high grade (G4) T2.

CONCLUSION

Tumour differentiation is an important prognostic factor. It correlates significantly with the overall stage of the TNM system and also to each of its components. The risk of having lymph node metastasis for each T-stage also correlates with the tumour grade. The findings can be of importance in postoperative risk assessment or when considering local resection procedures like TEM.

Colorectal Carcinoma: Local Tumor Staging and Assessment of Lymph Node Metastasis by High-Resolution MR Imaging in Surgical Specimens

Purpose. To assess the accuracy of high-resolution MR imaging as a means of evaluating mural invasion and lymph node metastasis by colorectal carcinoma in surgical specimens. Materials and Methods. High-resolution T1-weighted and T2-weighted MR images were obtained in 92 surgical specimens containing 96 colorectal carcinomas. Results. T2-weighted MR images clearly depicted the normal colorectal wall as consisting of seven layers. In 90 (94%) of the 96 carcinomas the depth of mural invasion depicted by MR imaging correlated well with the histopathologic stage. Nodal signal intensity on T2-weighted images (93%) and nodal border contour (93%) were more accurate than nodal size (89%) as indicators of lymph node metastasis, and MR imaging provided the highest accuracy (94%-96%) when they were combined. Conclusion. High-resolution MR imaging is a very accurate method for evaluating both mural invasion and lymph node metastasis by colorectal carcinoma in surgical specimens.

Human colon cancer profiles show differential microRNA expression depending on mismatch repair status and are characteristic of undifferentiated proliferative states

BACKGROUND

Colon cancer arises from the accumulation of multiple genetic and epigenetic alterations to normal colonic tissue. microRNAs (miRNAs) are small, non-coding regulatory RNAs that post-transcriptionally regulate gene expression. Differential miRNA expression in cancer versus normal tissue is a common event and may be pivotal for tumor onset and progression.

METHODS

To identify miRNAs that are differentially expressed in tumors and tumor subtypes, we carried out highly sensitive expression profiling of 735 miRNAs on samples obtained from a statistically powerful set of tumors (n = 80) and normal colon tissue (n = 28) and validated a subset of this data by qRT-PCR.

RESULTS

Tumor specimens showed highly significant and large fold change differential expression of the levels of 39 miRNAs including miR-135b, miR-96, miR-182, miR-183, miR-1, and miR-133a, relative to normal colon tissue. Significant differences were also seen in 6 miRNAs including miR-31 and miR-592, in the direct comparison of tumors that were deficient or proficient for mismatch repair. Examination of the genomic regions containing differentially expressed miRNAs revealed that they were also differentially methylated in colon cancer at a far greater rate than would be expected by chance. A network of interactions between these miRNAs and genes associated with colon cancer provided evidence for the role of these miRNAs as oncogenes by attenuation of tumor suppressor genes.

CONCLUSION

Colon tumors show differential expression of miRNAs depending on mismatch repair status. miRNA expression in colon tumors has an epigenetic component and altered expression that may reflect a reversion to regulatory programs characteristic of undifferentiated proliferative developmental states.

Effect of early preoperative 5-fluorouracil on the integrity of colonic anastomoses in rats

AIM: To determine the effect of chemotherapy on wound healing by giving early preoperative 5-fluorouracil (5-FU) to rats with colonic anastomoses.

METHODS: Sixty Albino-Wistar male rats (median weight, 235 g) were used in this study. The rats were fed with standard laboratory food and given tap water ad libitum. The animals were divided into three groups: Group 1: Control group (chemotherapy was not administered), Group 2: Intraperitoneally (IP) administered 5-FU group (chemotherapy was administered IP to animals at a dose of 20 mg/kg daily during the 5 d preceeding surgery), Group 3: Intravenously (IV) administered 5-FU group. Chemotherapy was administered via the penil vein, using the same dosing scheme and duration as the second group. After a 3-d rest to minimize the side effects of chemotherapy, both groups underwent surgery. One centimeter of colon was resected 2 cm proximally from the peritoneal reflection, then sutured intermittently and subsequently end-to-end anastomosed. In each group, half the animals were given anaesthesia on the 3rd postoperative (PO) day and the other half on the 7th PO day, for in vivo analytic procedures. The abdominal incisions in the rats were dissected, all the new and old anastomotic segments were clearly seen and bursting pressures of each anastomotic segment, tissue hydroxyproline levels and DNA content were determined to assess the histologic tissue repair process.

RESULTS: When the IV group was compared with the IP group, bursting pressures of the anastomotic segments on the 3rd and 7th PO days, were found to be significantly decreased, hydroxyproline levels at the anastomotic segment on the 7th PO day were significantly decreased (P < 0.01).

CONCLUSION: In this study, we conclude that early preoperative 5-FU, administered IV, negatively affects wound healing. However, IP administered 5-FU does not negatively affect wound healing.

The intratumoral distribution of nuclear beta-catenin is a prognostic marker in colon cancer

BACKGROUND

Most colon cancers harbor mutations of APC or beta-catenin, both of which may lead to nuclear beta-catenin accumulation in the tumor cells and constitutively activated expression of its target genes. In many colon cancers, however, nuclear beta-catenin accumulation is heterogeneous throughout the tumor and often confined to the tumor margin. Herein, the authors investigated whether the intratumoral distribution of nuclear beta-catenin can serve as a prognostic marker for survival and tumor progression of stage IIA colon cancer patients.

METHODS

In total, 142 patients with primarily resected, moderately differentiated stage IIA colon cancer were included in this study. The patterning of nuclear beta-catenin expression was evaluated on immunohistochemically stained whole tissue sections of the tumors and was correlated with cancer-specific survival and disease-free survival using univariate and multivariate statistical analyses.

RESULTS

Four distinct patterns of nuclear beta-catenin expression were identified, and 2 main categories comprising tumors with or without intratumoral regulation of nuclear beta-catenin were distinguished. Moreover, the results demonstrated that the patterning, and especially the regulation or absence of regulation of nuclear beta-catenin expression, was a strong predictive marker of patient survival and tumor progression.

CONCLUSIONS

The current results indicated that the distribution of nuclear beta-catenin expression can be used as a good prognostic marker in patients with stage IIA colon cancer. Thus, the evaluation of nuclear beta-catenin may help to identify patients who will have a shorter than average survival and patients with a greater risk of disease progression who may be considered for adjuvant therapeutic modalities and intensified clinical aftercare in the future.

A study of lymph node ratio in stage IV colorectal cancer

BACKGROUND

The finding of metastasis in colorectal cancer, stage IV disease, has a major impact on prognosis and treatment strategy. Known important factors include the extent of the metastasis and the patients' performance status. The lymph node factors are of known importance in earlier cancer stages but less described in metastatic disease. The aim of the study was to evaluate lymph node status and ratio as prognostic markers in stage IV colorectal cancer.

METHODS

The study was retrospective and assessing all patients operated, with bowel resection, for an initial stage IV colorectal cancer during 1999-2003 (n = 136). Basic demographic data as well as given treatment was assessed. The Lymph node ratio (LNR), the quota between the number of lymph node metastasis and assessed lymph nodes, was calculated. LNR groups were created by ratio thirds, 3 equally sized groups. The analysis was made by LNR group and by eligibility for chemotherapy with cancer specific survival as outcome parameter.

RESULTS

The median survival (CSS) for the entire group was 431 days with great variability. For the patients eligible for chemotherapy it ranged from 791 days in LNR-group 1 to 433 days for the patients in group 3. For patients ineligible for chemotherapy the corresponding figures were 209 and 91 days. The eligibility for chemotherapy was a major prognostic factor which also takes co-morbidity, age and performance status into consideration. The LNR (p < 0.01) and the tumour differentiation grade were also significant (p < 0.05) factors regarding survival. The LNR group 3 was also associated with a higher frequency of multiple metastasis locations (p < 0.05) and of more side effects with chemotherapy and thus of reductions in dosage or pre-emptive treatment ending (p < 0.05).

CONCLUSION

Stage IV colorectal cancer is a heterogeneous group regarding the survival prognosis. The lymph node ratio was found to be a significant marker for the survival prognosis (p < 0.0049). High and low risk groups could be identified with a survival difference of up to one year. It could be of importance when planning a treatment strategy or evaluating clinical data materials. A pathology report should include a node assessment even at presence of synchronous metastasis.

A study of lymph node ratio as a prognostic marker in colon cancer

AIM

The aim of this study was to evaluate and describe the lymph node ratio (LNR) as a prognostic parameter for patients with colon cancer. As lymphatic involvement is the key, focus was set at stage III disease. Interest was directed at the possibility of identifying high-risk groups and the clinical implementation and consequence.

METHOD

The study was retrospective using a database of clinical data of all cancer patients treated at our unit. It has been continuous in registration, inclusion and update since 1999 including survival and clinical features. All patients (n=265) diagnosed with stage III colon cancer during 1999-2003 were included for the study. LNR was calculated and quartile groups were created. LNR and associated parameters were analysed towards 3-year disease-free survival (DFS). Basic patient data as well as surgery, pathology and postoperative treatment were taken into consideration.

RESULTS

Significant differences in disease-free survival were found for TNM N-status, tumour differentiation grade and LNR quartile group. There was a difference in 3-year DFS from 80% in LNR group 1 compared with less than 30% in group 4. These results were of prognostic interest both independently and in interaction with each other. High-risk groups could be identified and in the worst prognosis LNR group we also found a tendency towards more side effects with adjuvant chemotherapy.

CONCLUSION

The lymph node ratio, the quota between the number of lymph node metastasis and assessed lymph nodes, is a highly significant (p<0.001) prognostic factor in stage III colon cancer. It can be an aid in identifying risk groups that could benefit from a more intense postoperative surveillance and possibly bring changes in adjuvant treatment strategy. More studies of clinical data, genetic and biochemical markers are needed in this patient group to understand the possible difference in tumour behaviour and tailor the treatment.

Colorectal carcinoma: in vitro evaluation with high-spatial-resolution 3D constructive interference in steady-state MR imaging

PURPOSE

To retrospectively assess the accuracy of high-spatial-resolution three-dimensional (3D) constructive interference in steady-state (CISS) magnetic resonance (MR) imaging in the evaluation of mural invasion of colorectal carcinoma by using prospectively obtained in vitro images, with histopathologic analysis as the reference standard.

MATERIALS AND METHODS

Institutional review board approval was obtained for the prospective and retrospective components of this study, with informed consent for the former and waiver of informed consent for the latter. Surgical specimens were obtained in 92 patients (61 men, 31 women; mean age, 65 years) and contained 96 colorectal carcinomas. Specimens were examined with a 1.5-T MR system and a 4-cm-diameter loop coil. High-spatial-resolution 3D CISS MR images were obtained with 80 x 80-mm field of view, 512 x 512 matrix, and 0.7-mm section thickness, which resulted in a 0.017-mm(3) voxel size. The 3D data sets were postprocessed with surface-rendering software to generate virtual MR endoscopic images. The 3D CISS MR images were compared with histopathologic findings, and virtual MR endoscopic images were compared with macroscopic findings at surgery. Statistical analysis was performed with Spearman rank correlation.

RESULTS

In 92 (96%) colorectal carcinomas, the depth of mural invasion depicted by 3D CISS MR imaging correlated well with the histopathologic stage, although the stage assigned with 3D CISS MR imaging was higher than that assigned with histopathologic analysis in four (4%) carcinomas (r = 0.976, P < .001). Sensitivity, specificity, and accuracy were 100%, 94%-96%, and 98%-100%, respectively. In 91 (95%) carcinomas, virtual MR endoscopy clearly depicted the macroscopic type of carcinoma, including gross configuration and tumor ulceration (r = 0.916, P < .001).

CONCLUSION

High-spatial-resolution 3D CISS MR imaging has high diagnostic accuracy in the in vitro evaluation of mural invasion and macroscopic features of colorectal carcinomas.

p66 Shc Tumor Levels Show a Strong Prognostic Correlation with Disease Outcome in Stage IIA Colon Cancer

PURPOSE

Most stage IIA colon cancer patients receive no adjuvant therapy despite an estimated 15% risk of disease-related death within 5 years of resection. Prognostication of disease outcome would benefit the clinician by categorizing patients with stage IIA disease by risk. The abundance of the signal transduction proteins p66 Shc and tyrosine-phosphorylated (PY)-Shc in tumor cells is a prognostic indicator of disease outcome in breast cancer, suggesting that Shc analysis may provide prognostic information in stage IIA colon cancer.

EXPERIMENTAL DESIGN

Immunohistochemical staining of p66 Shc and PY-Shc was examined in resection specimens from 240 chemotherapy-naïve patients with stage IIA (T(3)N(0)M(0)) colon cancer from two independent (130 and 110 cases, respectively) retrospective cohorts. Staining was scored on a 0 to 5 scale and correlated with relapse-free survival and disease-specific survival in a multivariate analysis to obtain hazard ratios (HR) for both outcomes.

RESULTS

In a pooled analysis of both cohorts, p66 Shc score was a significant prognostic indicator of relapse-free survival (full-range HR, 13.0; P = 0.012) and disease-specific survival (full-range HR, 36.6; P = 0.004) when analyzed as a continuous variable in a multivariate Cox proportional hazards model stratified by study site and adjusted for age, sex, grade, and lymphovascular involvement. PY-Shc in this multivariate Cox model, however, did not achieve statistical significance for either outcome.

CONCLUSIONS

Measuring p66 Shc tumor levels provides a unique and simple tool for stratifying stage IIA colon cancer patients by risk of recurrence and disease-specific death and may assist in determining treatment strategies for these patients.

Stage migration in colorectal cancer related to improved lymph node assessment

AIM

The aim of the study was to evaluate the clinical impact of improved cooperation between the treating surgeons and pathologists in a high volume surgical unit. As a measure we used the staging process with special focus on lymph node assessment.

FINDINGS

Comparing two periods 5 years apart, we found a significant increase in the number of nodes examined and also an increase in the number of metastasis-positive nodes. Concurrently, we observed a trend in stage migration from stage I/II towards stage III, whilst stage IV remained unchanged. This was one factor that contributed to an increase in the number of patients treated with adjuvant chemotherapy. We also found that the number of assessed nodes had an impact on survival in stage II. The major change in practise was the implementation of a multidisciplinary team conference and the associated possibility of reciprocal feedback.

CONCLUSION

Lymph node status has a key role in cancer staging and in the selection of further therapy. The quality and the standard of the assessment can be improved through multidisciplinary cooperation and it has an impact on the clinical decisions and can affect long-term survival. A correct node status should be mandatory in the evaluation of prognostic factors.

The impact of postoperative complications on long-term outcomes following curative resection for colorectal cancer

BACKGROUND

This study aimed to investigate the impact of postoperative complications on long-term survival and disease recurrence in patients who underwent curative resection for colorectal cancer.

METHOD

Patients who underwent radical resection for colorectal cancer with curative intent from January 1996 to December 2004 were included. Operative mortality and morbidity were documented prospectively. Factors that might affect long-term outcome were analyzed with multivariate analysis.

RESULTS

Curative resection was performed in 1657 patients (943 men), and the median age was 70 years (range: 24-94 years). The 30-day mortality was 2.4%, and the complication rate was 27.3%. Age over 70 years (P < .001, odds ratio: 2.06, 95% CI: 1.63-2.61), male gender (P = .001, odds ratio: 1.49, 95% CI: 1.19-1.88), emergency operation (P < .001, odds ratio: 3.14, 95% CI: 2.26-4.35) and rectal cancer (P < .001, odds ratio: 1.41, 95% CI: 1.25-1.61) were associated with a significantly higher complication rate. With exclusion of patients who died within 30 days, the median follow-up of the surviving patients was 45.3 months. The 5-year overall survival was 64.9%, and the overall recurrence rate was 29.1%. The presence of postoperative complications was an independent factor associated with a worse overall survival (P = .023, hazard ratio: 1.26; 95% CI: 1.03-1.52) and a higher overall recurrence rate (P = .04, hazard ratio: 1.26; 95% CI: 1.01-1.57).

CONCLUSION

The presence of postoperative complication not only affects the short-term results of resection of colorectal cancer, but the long-term oncologic outcomes are also adversely affected. Long-term outcomes can be improved with efforts to reduce postoperative complications.

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.