Changes on the disease pattern of primary colorectal cancers in Southern China: a retrospective study of 20 years

Red Flag Signs and Symptoms for Patients With Early-Onset Colorectal Cancer: A Systematic Review and Meta-Analysis

Importance

Early-onset colorectal cancer (EOCRC), defined as a diagnosis at younger than age 50 years, is increasing, and so-called red flag signs and symptoms among these individuals are often missed, leading to diagnostic delays. Improved recognition of presenting signs and symptoms associated with EOCRC could facilitate more timely diagnosis and impact clinical outcomes.

Objective

To report the frequency of presenting red flag signs and symptoms among individuals with EOCRC, to examine their association with EOCRC risk, and to measure variation in time to diagnosis from sign or symptom presentation.

Data Sources

PubMed/MEDLINE, Embase, CINAHL, and Web of Science were searched from database inception through May 2023.

Study Selection

Studies that reported on sign and symptom presentation or time from sign and symptom presentation to diagnosis for patients younger than age 50 years diagnosed with nonhereditary CRC were included.

Data Extraction and Synthesis

Data extraction and quality assessment were performed independently in duplicate for all included studies using Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guidelines. Joanna Briggs Institute Critical Appraisal tools were used to measure risk of bias. Data on frequency of signs and symptoms were pooled using a random-effects model.

Main Outcomes and Measures

Outcomes of interest were pooled proportions of signs and symptoms in patients with EOCRC, estimates for association of signs and symptoms with EOCRC risk, and time from sign or symptom presentation to EOCRC diagnosis.

Results

Of the 12 859 unique articles initially retrieved, 81 studies with 24 908 126 patients younger than 50 years were included. The most common presenting signs and symptoms, reported by 78 included studies, were hematochezia (pooled prevalence, 45% [95% CI, 40%-50%]), abdominal pain (pooled prevalence, 40% [95% CI, 35%-45%]), and altered bowel habits (pooled prevalence, 27% [95% CI, 22%-33%]). Hematochezia (estimate range, 5.2-54.0), abdominal pain (estimate range, 1.3-6.0), and anemia (estimate range, 2.1-10.8) were associated with higher EOCRC likelihood. Time from signs and symptoms presentation to EOCRC diagnosis was a mean (range) of 6.4 (1.8-13.7) months (23 studies) and a median (range) of 4 (2.0-8.7) months (16 studies).

Conclusions and Relevance

In this systematic review and meta-analysis of patients with EOCRC, nearly half of individuals presented with hematochezia and abdominal pain and one-quarter with altered bowel habits. Hematochezia was associated with at least 5-fold increased EOCRC risk. Delays in diagnosis of 4 to 6 months were common. These findings highlight the need to identify concerning EOCRC signs and symptoms and complete timely diagnostic workup, particularly for individuals without an alternative diagnosis or sign or symptom resolution.

Alexithymia is associated with insomnia in Chinese patients with schizophrenia

Background

Sleep disorders are prevalent among patients with schizophrenia and are associated with several negative consequences. Although, researchers have recently suggested that sleep disorders have a close correlation with alexithymia, and schizophrenia also has a strong correlation with alexithymia, there have been few studies on the relationships between schizophrenia, sleep disorders and alexithymia. Therefore, this study aimed to explore the relationships between psychiatric symptoms, alexithymia and sleep problems in patients with schizophrenia so as to provide a reference for the clinical treatment of this comorbidity.

Methods

In total, 977 patients with schizophrenia were recruited for this study. The Insomnia Severity Index (ISI) was used to assess sleep disorders, and the Positive and Negative Syndrome Scale (PANSS), Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) and Toronto Alexithymia Scale (TAS) were used to evaluate clinical symptoms, cognitive functions and the ability to express emotion, respectively.

Results

The results indicated that the PANSS subscales (G-subscore) and TAS group were risk factors for insomnia in schizophrenia patients (all p < 0.05). The mediation model showed the standardized path coefficients from schizophrenia to alexithymia (β = 0.104, p < 0.001) and from alexithymia to insomnia (β = 0.038, p < 0.001) were statistically significant.

Conclusion

The results of this study indicated that alexithymia is associated with sleep disturbance in patients with schizophrenia. These findings may provide a new avenue for the treatment of schizophrenia patients with sleep disorders.

The prognostic impact of BMI on colorectal cancer is stratified by tumor location

Purpose

Recent studies have revealed the contrasting prognostic roles of body mass index (BMI) and tumor location in colorectal cancer (CRC). Given that right- and left-sided CRC may exhibit inverse effects on outcome and body weight, the present study aimed to examine whether the prognostic value of BMI and tumor location could be reciprocally stratified.

Methods

This prospective, observational study recruited 4,086 patients diagnosed with stage III CRC from five independent clinical centers in China. The association of patients’ outcomes with BMI and tumor location was evaluated hierarchically by Kaplan–Meier and Cox proportional-hazards models.

Results

Although BMI was not associated with overall outcome, the association was significantly modified by tumor location. Among left-sided tumors, obesity and overweight were significantly associated with adverse overall survival (OS) and disease-specific survival (DSS). In contrast, among right-sided tumors, overweight was significantly associated with more favorable OS and DSS compared with the normal-weight group. The association of survival with tumor location did not reach statistical significance. However, hierarchical analysis by BMI revealed that left-sided tumors were associated with more favorable outcomes in the normal-weight group, while there was no statistically significant difference in the overweight or obese group.

Conclusions

BMI and tumor location may have opposing effects on CRC prognosis, when stratified by each other, after adjusting for other known prognostic factors. These findings are the first to show the interactive prognostic impact of BMI and tumor location, which could be relevant to the stratification of patient management.

Effect of antifoaming agent on benign colorectal tumors in colonoscopy: A meta-analysis

BACKGROUND

Although several trials have shown that the addition of antifoaming agents to polyethylene glycol (PEG) can improve bowel preparation, whether PEG plus antifoaming agents have a beneficial role in the detection of benign tumors during colonoscopy has yet to be confirmed. Our aim was to clarify whether adding simethicone to PEG solution could improve the detection of benign colorectal tumors.

AIM

To clarify whether adding simethicone to PEG solution could improve the detection of benign colorectal tumors.

METHODS

The PubMed, EMBASE, and Cochrane Library databases were searched for articles published prior to September 2019. The outcomes included the detection rates of colorectal adenomas and polyps.

RESULT

Twenty studies were eligible. Although there was no difference in the colorectal adenoma detection rate (ADR), a significant effect of simethicone for diminutive adenomas (< 10 mm) was revealed in the group taking simethicone. We also found that simethicone could significantly improve the ADR in the proximal colon but did not affect the colorectal polyp detection rate. Furthermore, the subgroup analyses revealed a beneficial effect of simethicone on the ADR among Asians (P = 0.005) and those with an ADR < 25% (P = 0.003). Moreover, it was a significant finding that the low dose simethicone was as effective as the high dose one with respect to the detection of benign colorectal tumors.

CONCLUSION

In summary, the addition of simethicone to PEG might improve the detection of diminutive adenomas in the right colon by colonoscopy in Asia. Low-dose simethicone was recommended for the detection of benign colorectal tumors. However, large clinical trials are necessary to validate our results and determine the ideal dose of simethicone.

Current status of surgical treatment of rectal cancer in China

With the changing lifestyle and the acceleration of aging in the Chinese population, the incidence and mortality of colorectal cancer (CRC) have risen in the last decades. On the contrary, the incidence and mortality of CRC have continued to decline in the USA since the 1980s, which is mainly attributed to early screening and standardized diagnosis and treatment. Rectal cancer accounts for the largest proportion of CRC in China, and its treatment regimens are complex. At present, surgical treatment is still the most important treatment for rectal cancer. Since the first Chinese guideline for diagnosis and treatment of CRC was issued in 2010, the fourth version has been revised in 2020. These guidelines have greatly promoted the standardization and internationalization of CRC diagnosis and treatment in China. And with the development of comprehensive treatment methods such as neoadjuvant chemoradiotherapy, targeted therapy, and immunotherapy, the post-operative quality of life and prognosis of patients with rectal cancer have improved. We believe that the inflection point of the rising incidence and mortality of rectal cancer will appear in the near future in China. This article reviewed the current status and research progress on surgical therapy of rectal cancer in China.

Impact of simethicone on bowel cleansing during colonoscopy in Chinese patients

BACKGROUND

Four-liter polyethylene glycol (PEG) solutions are effective for bowel cleansing, but their large volume might hinder patient compliance. Due to the unique features of Asians, 4 L PEG might be a suboptimal bowel preparation in predominantly ethnically Asian countries. In view of this, a balance should be achieved between the volume and effectiveness. The ideal bowel cleansing regimen for a colonoscopy has yet to be determined in a Chinese population.

AIM

To compare the cleansing efficacy of 3 L PEG plus simethicone with 4 L PEG.

METHODS

A total of 291 patients were randomly allocated to two groups: Group 1 (n = 145) received 4 L split-dose PEG (4-P); group 2 (n = 146) received 3 L split-dose PEG plus simethicone (3-PS). Bowel-cleansing efficacy was evaluated by endoscopists using the Boston bowel preparation scale (BBPS) and the bubbles score.

RESULTS

Although there were no significant differences in the total BBPS score or the adequate rate of bowel preparation between the two groups, the BBPS score of the right-side colon was significantly higher in the 3-SP group (2.37 ± 0.54 vs 2.21 ± 0.78; P = 0.04). Moreover, the use of simethicone significantly reduced bubbles in all colon segments (P < 0.001). The mean withdrawal time was significantly shorter in the 3-PS group (8.8 ± 3.4 vs 9.6 ± 2.3; P = 0.02). Furthermore, significantly more proximal adenomas were detected in the 3-PS group (53.6% vs 45.7%; P = 0.03). In addition, the proportions of patients with nausea and bloating were significantly lower in the 3-SP group (P < 0.01 for both). More patients in the 3-PS group expressed willingness to repeat the bowel preparation (87.7% vs 76.6%, P = 0.01).

CONCLUSION

Three-liter PEG shows satisfactory bowel cleansing despite the decrease in dosage, and addition of simethicone with better bubble elimination and enhanced patient acceptance offers excellent potential impact on the detection of proximal adenomas in Chinese patients.

Gender aspects of survival after abdominoperineal resection for low rectal cancer: a retrospective study

PURPOSE

The difference in prognosis between genders after abdominoperineal resection (APR) for low rectal cancer (LRC) is unclear. This study aimed to compare survival outcomes between genders in patients with LRC who underwent curative APR.

METHODS

This retrospective cohort study used a database of consecutive colorectal resections. Patients who received curative APR with LRC were grouped according to their gender. Female patients were frequency-matched 1:1 on American Joint Committee on Cancer (AJCC) stage to male patients. Overall survival (OS), disease-free survival (DFS), and their independent risk factors were examined.

RESULTS

A total of 140 patients with APR for LRC were included after matching: 70 (50.0%) males and 70 (50.0%) females. No significant differences were found between the groups in terms of age, operation methods, AJCC stage, and adjuvant therapy (all P > 0.05). Median follow-up was 39 (range: 3-128) months. Male gender was independently associated with worse OS (adjusted hazard ratio [HR] = 2.755, 95% CI: 1.507-5.038, P = 0.001) and worse DFS (adjusted HR = 2.440, 95% CI: 1.254-4.746, P = 0.009). Subgroup analysis revealed that female patients with stage III disease had better OS (P = 0.001) and DFS (P < 0.001) than male patients.

CONCLUSION

Gender affects survival after a curative APR for LRC. Compared with females, male patients with LRC after curative APR had worse prognosis, especially for stage III disease.

Surgical treatment of massive stoma site tumors after a curative operation for rectal cancer

OBJECTIVE

This study aimed to evaluate the clinical and oncological outcomes of selected rectal cancer patients with massive stoma site tumors who underwent radical resection and reconstruction.

METHODS

We reviewed 8 cases of massive stoma site tumors in patients who had permanent gastrointestinal stoma in the abdominal wall following radical resection of rectal cancer between March 2013 and May 2018 at the Peking University Cancer Hospital and Peking University Shougang Hospital.

RESULTS

There were seven males and one female patient, with a median age of 50.6 years. The average time between the initial surgery and the development of a malignant tumor at the stoma site was 5 years (range, 0.5-14 years). The average diameter of the stoma site tumors was 8.1 cm, and the diameter of the largest tumor was 12 cm. After tumor resection, the area of the largest abdominal wall defect was about 15 × 14 cm². Abdominal wall repair included the use of a tensor fasciae latae muscle flap, local fasciocutaneous rotational flap, and pedicled anterolateral thigh flap. No patient died in the 30 days following surgery. The longest follow-up period was 81 months, and 5 patients died.

CONCLUSIONS

Multidisciplinary clinical management fosters positive outcomes in treating massive stoma site tumors. Local R0 resection and abdominal wall reconstruction are safe and feasible, and function to removes local disease, allowing patients to live a higher quality of life.

Upregulation of MiR-1274a is Correlated with Survival Outcomes and Promotes Cell Proliferation, Migration, and Invasion of Colon Cancer

Purpose

Colon cancer has become one of the primary causes of cancer-related mortality in recent years. MicroRNAs (miRNAs) play important roles in the regulation of target genes expression. Some of these molecules are aberrantly expressed in colon cancer. The aim of this study was to investigate the potential role of miR-1274a in colon cancer.

Patients and Methods

The expression levels of miR-1274a in colon cancer tissues and cell lines were detected using RT-qPCR. The association between miR-1274a expression and clinical features was analyzed by the χ² test. Then the Kaplan–Meier method and multivariate Cox regression analysis were used to explore the clinical prognostic significance of miR-1274a in colon cancer. Finally, the effects of miR-1274a on cell growth, migration, and invasion were investigated with the CCK-8 assay, colony formation assay, transwell migration, and invasion assays, respectively.

Results

The expression of miR-1274a was increased in colon cancer tissues and cell lines. The miR-1274a expression was associated with lymph node metastasis, vascular invasion, and TNM stage. Patients with high miR-1274a expression had a poor overall survival time compared with those with low miR-1274a expression. Upregulated miR-1274a promoted cell proliferation, migration, and invasion of colon cancer cells, while inhibition of miR-1274a suppressed these cellular activities by targeting FOXO4.

Conclusion

Our study suggested that miR-1274a might function as an oncogene in human colon cancer and be a potential prognostic biomarker and therapeutic target for the treatment of colon cancer.

Disease characteristics and treatment patterns of Chinese patients with metastatic colorectal cancer: a retrospective study using medical records from China

Background

Colorectal cancer (CRC) is the third most prevalent cancer in China but few large-scale studies were conducted to understand CRC patients. The current study is aimed to gain a real-world perspectives of CRC patients in China.

Methods

Using electronic medical records of sampled patients between 2011 and 2016 from 12 hospitals in China, a retrospective cohort study was conducted to describe demographics and disease prognosis of CRC patients, and examine treatment sequences among metastatic CRC (mCRC) patients. Descriptive, comparative and survival analyses were conducted.

Results

Among mCRC patients (3878/8136, 48%), the fluorouracil, leucovorin, and oxaliplatin (FOLFOX) and other oxaliplatin-based regimens were the most widely-used first-line treatment (42%). Fluorouracil, leucovorin, irinotecan (FOLFIRI) and other irinotecan-based regimens dominated the second-line (40%). There was no a dominated regimen for the third-line. The proportion of patients receiving chemotherapy with targeted biologics increased from less than 20% for the first- and second- lines to 34% for the third-line (p < 0.001). The most common sequence from first- to second-line was from FOLFOX and other oxaliplatin-based regimens to FOLFIRI and other irinotecan-based regimens (286/1200, 24%).

Conclusions

Our findings reflected a lack of consensus on the choice of third-line therapy and limited available options in China. It is evident o continue promoting early CRC diagnosis and to increase the accessibility of treatment options for mCRC patients. As the only nationwide large-scale study among CRC and mCRC patients before more biologics became available in China, our results can also be used as the baseline to assess treatment pattern changes before and after more third-line treatment were approved and covered into the National Health Insurance Plan in China between 2017 and 2018.

Epidemiology and risk factors of colorectal cancer in China

In China, colorectal cancer (CRC) ranked fourth and fifth in the highest incidence and mortality rates of all malignancies in 2018, respectively. Although these rates are below the world average, China placed first worldwide in the number of new CRC cases and CRC-related deaths because of its comparatively large population. This disease represents a threat to the health of population and incurs a heavy economic burden on the society and individuals. CRC has various risk factors, including age, sex, lifestyle, genetic factors, obesity, diabetes, gut microbiota status, and precancerous lesions. Furthermore, incidence and mortality rates of CRC are closely related to socioeconomic development levels, varying according to regional and population characteristics. Prevention is the main strategy to reduce incidence and mortality rates of CRC. This can be achieved through strategies stimulating lifestyle changes, healthy diet habits, and early screening for high-risk individuals. To reduce the burden of CRC, public health officials should promote prevention and management of modifiable risk factors through national policies. The rising incidence and mortality rates of CRC in China may be timely curbed by clarifying specific epidemiological characteristics, optimizing early screening strategies, and strictly implementing diagnosis and treatment guidelines. Thus, this study aimed to collect and report the current research status on epidemiology and risk factors of CRC in China.

Reevaluation of a rightward shift in colorectal cancer: A single-center retrospective study in Tianjin

OBJECTIVES

Some Western reports have shown a proximal shift in colorectal cancer (CRC), but there are few studies in China. This study aimed to provide more information for the management and screening of CRC by investigating trends in the anatomic distribution of CRC among the Chinese population in recent years.

METHODS

A retrospective study was conducted on patients with CRC admitted to the Digestive Endoscopy Center of Tianjin Medical University General Hospital between January 2000 and December 2017. Patients were divided into a left-sided colorectal cancer (LSCRC) group and a right-sided colon cancer (RSCC) group. The detection rates of LSCRC and RSCC based on patients' age and sex, and on the time periods were analyzed.

RESULTS

A total of 2319 cases were diagnosed with CRC among 75 183 consecutive patients. The prevalence of CRC showed a significant reduction from 2000-2008 to 2009-2017 (3.8% vs 2.7%, P < .001). The proportion of RSCC presented a downtrend from 2000-2008 to 2009-2017 (40.6% vs 37.7%, P > .05). There were slightly more RSCCs in female patients than in male patients, with no significant difference (40.9% vs 36.5%, P > .05). The proportion of RSCC in patients aged ≥50 years was similar to that in younger patients. The alarming symptoms between LSCRC and RSCC showed a significant difference (P < .05).

CONCLUSIONS

In the present study, the prevalence of CRC declined significantly with time. However, there did not appear to be a rightward shift in CRC among the patients in Tianjin over the past 18 years.

Analysis of population-based colorectal cancer screening in Guangzhou, 2011-2015

Objective

To analyze the detection rates of colorectal cancer (CRC) and polyps by population‐based screening in Guangzhou.

Methods

From January 2011 to December 2015, the residents aged 30‐79 were selected for CRC screening. The residents were conducted Questionnaires and/or FOBT to assess high‐risk groups, the free colonoscopy examination was recommended, and the results were evaluated in detail.

Results

There were 98 927 residents involving screening, 5306 high‐risk residents identified (males 1859 and females 3447), and 4713 subjects underwent colonoscopy (males 1690 and females 3023). CRC was seen in 55 individuals (males 28 and females 27), and the detection rates in male were higher than in female (P = 0.019). And the detection rates increasing with age, for people over 60 years old, were obviously higher than those younger (x² = 18.64, P = 0.000924).

The polyps were seen in 1458 (30.94%) cases， and 1420 subjects received pathological examination (adenomas 971 and non‐adenomatous polyps 449). Advanced adenomas were seen in 462 cases (males 240 and females 222) and 509 cases of non‐advanced adenomas (males 255 and females 254). For advanced adenomas, the detection rates in male were higher than female (14.20% vs 7.34%, P = 2.64 × 10⁻¹⁴). For the detection rates of adenomas or advanced adenomas by age, the people over 40 years were higher than younger (20.91% vs 3.61% P = 7.87 × 10⁻⁶; 9.94% vs 2.41%, P = 0.009).

Conclusions

For Guangzhou residents, the detection rates of CRC and adenoma were 1.17% and 20.60%. The detection rates of CRC increasing with age, for people over 60 years old, were obviously higher than those younger. But for people over 40 years, the detection rate of adenoma and advanced adenoma was higher than younger. So for people over 40 years, the CRC screening is recommended.

Cartilage oligomeric matrix protein is a prognostic factor and biomarker of colon cancer and promotes cell proliferation by activating the Akt pathway

PURPOSE

Recent studies have determined that cartilage oligomeric matrix protein (COMP) plays a vital role in carcinogenesis. We sought to clarify the role of COMP in colon cancer.

METHODS

We investigated gene expression data from The Cancer Genome Atlas (TCGA) dataset. Tissue microarrays (TMA) containing paired samples from 253 patients with colon cancer were subjected to immunostaining. COMP levels in serum of colon cancer patients and healthy donors were measured with ELISA. We established COMP-knockout cells using the CRISPR/Cas9 system and COMP-overexpressing cells using lentiviral vectors to detect the effects of COMP on colon cancer cells using Cell Counting Kit-8 (CCK8), colony formation, apoptosis detection kit, and tumorigenesis assays in nude mice.

RESULTS

The analysis of TCGA dataset and the results of the TMA suggested that COMP expression levels were significantly higher in cancer tissues than in adjacent normal tissues. Moreover, high COMP expression was correlated with the poor outcome of colon cancer patients. COMP levels in the sera of preoperative patients with colon cancer were much higher than those in healthy donors and were significantly reduced after colectomy. Colon cancer cells without COMP were defective with respect to the ability to proliferate, colony formation, the ability to resist 5-Fluorouracil-induced apoptosis and the growth of xenograft tumors in mice. Contrasting results were observed in COMP overexpressed cells. COMP promoted colon cancer cell proliferation partially through the activation of PI3K/ Akt/ mTOR/ p70S6K pathway.

CONCLUSIONS

COMP may be a novel prognostic indicator and biomarker and also a potential therapeutic target for colon cancer.

NOTCH4 regulates colorectal cancer proliferation, invasiveness, and determines clinical outcome of patients

Notch signal has complex roles in human malignancies, which might be attributed to the diversity of Notch receptors. Here, we set out to identify the association of NOTCH4 with colorectal cancer (CRC). In the hospital-based study cohort, we investigated NOTCH4 mRNA levels in primary CRC, as well as its association with clinicopathologic characteristics. Besides, NOTCH4 cDNA and siRNA was transfected into colorectal cancer cell line to elucidate its impact on tumor cell proliferation and migration. Results revealed a statistically significant lower expression of NOTCH4 mRNA in tumor specimens compared with that in control. NOTCH4 level in CRC was found to be related to tumor differentiation, invasion, and node metastasis. Moreover, it was demonstrated that NOTCH4 mRNA level could be an independent prognostic factor for both disease-free and overall survival of CRC patients. Overexpression of NOTCH4 in CRC cell lines suppressed tumor cell proliferation, migration, and invasion, while induced apoptosis. In the opposite, the malignant behavior of CRC cells was enhanced by NOTCH4 knockdown. These results demonstrated for the first time that NOTCH4 expression was decreased in CRC, which could determine tumor proliferation, relapse, and prognosis.

Dietary patterns and colorectal cancer risk: a meta-analysis

The analysis of dietary patterns has recently drawn considerable attention as a method of investigating the association between the overall whole diet and the risk of colorectal cancer. However, the results have yielded conflicting findings. Here, we carried out a meta-analysis to identify the association between dietary patterns and the risk of colorectal cancer. A total of 40 studies fulfilled the inclusion criteria and were included in this meta-analysis. The highest category of 'healthy' dietary pattern compared with the lowest category was apparently associated with a decreased risk for colorectal cancer [odds ratio (OR)=0.75; confidence interval (CI): 0.68-0.83; P<0.00001]. An increased risk of colorectal cancer was shown for the highest compared with the lowest category of a 'western-style' dietary pattern (OR=1.40; CI: 1.26-1.56; P<0.00001). There was an increased risk of colorectal cancer in the highest compared with the lowest category of 'alcohol-consumption' pattern (OR=1.44; CI: 1.13-1.82; P=0.003). The results of this meta-analysis indicate that a 'healthy' dietary pattern may decrease the risk of colorectal cancer, whereas 'western-style' and 'alcohol-consumption' patterns may increase the risk of colorectal cancer.

Rectal Cancer in Asian vs. Western Countries: Why the Variation in Incidence?

OPINION STATEMENT

Colorectal cancer (CRC) is the third most common cancer worldwide. CRC has been thought to be less common in Asia compared to Western countries. However, the incidence rates of CRC in Asia are high and there is an increasing trend in the Asian population. Furthermore, colorectal cancer accounts for the greatest number of all incidences of CRC in Asia. The increasing adoption of a Western lifestyle, particularly in dietary habits, is likely the most important factor contributing to the rapid increase in colon cancer incidence; it is noteworthy that trends for rectal cancer were flat. The etiology of colon and rectal cancer is a bit different. The risks of distal colon and rectal cancers are more likely to be related to environmental factors, such as polluted surface water sources, alcohol consumption, and habitual smoking. The lack of great change in the incidence of rectal cancer might be due to weaker associations with such lifestyle factors. Therefore, it has been hypothesized that proximal and distal sections of the colon and rectum are two different organs in terms of function and genetic background. It may mean differences in differential sensitivities and exposures to carcinogens. However, despite the decrease in whole incidence, the CRC incidence in young adults in Western countries are reversely increasing, especially in rectal cancer, due to reasons largely unknown. Although the treatment algorithm is different between Asia and western countries, globally, the survival rate for patients with rectal cancer has risen during the past 10 years. Screening contributes a great deal to reducing the incidence and improving survival. Most countries in Asia, such as China, need nationwide registration and screening systems to provide better data.

Genome-wide analysis of long non-coding RNA expression and function in colorectal cancer

Long non-coding RNAs (lncRNAs) are widely transcribed in the genome, but their expression profile and roles in colorectal cancer are not well understood. The aim of this study was to investigate the long non-coding RNA expression profile in colorectal cancer and look for potential diagnostic biomarkers of colorectal cancer. Long non-coding RNA microarray was applied to investigate the global long non-coding RNA expression profile in colorectal cancer. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses were performed using standard enrichment computational methods. The expression levels of selected long non-coding RNAs were validated by quantitative reverse transcription polymerase chain reaction. The relationship between long non-coding RNA expression levels and clinicopathological characteristics of colorectal cancer patients was assessed. Coexpression analyses were carried out to find the coexpressed genes of differentially expressed long non-coding RNAs, followed by gene ontology analysis to predict the possible role of the selected long non-coding RNAs in colorectal carcinogenesis. In this study, a total of 1596 long non-coding RNA transcripts and 1866 messenger RNA transcripts were dysregulated in tumor tissues compared with paired normal tissues. The top upregulated long non-coding RNAs in tumor tissues were CCAT1, UCA1, RP5-881L22.5, NOS2P3, and BC005081 and the top downregulated long non-coding RNAs were AK055386, AC078941.1, RP4-800J21.3, RP11-628E19.3, and RP11-384P7.7. Long non-coding RNA UCA1 was significantly upregulated in colon cancer, and AK055386 was significantly downregulated in tumor with dimension <5 cm. Functional prediction analyses showed that both the long non-coding RNAs coexpress with cell cycle related messenger RNAs. The current long non-coding RNA study provided novel insights into expression profile in colorectal cancer and predicted the potential roles of long non-coding RNAs in colorectal carcinogenesis. Among the dysregulated long non-coding RNAs, UCA1 was found to be associated with anatomic site, and AK055386 was found associated with tumor size. Further functional investigations into the molecular mechanisms are warranted to clarify the role of long non-coding RNA in colorectal carcinogenesis.

Elevated expression of KLK8 predicts poor prognosis in colorectal cancer

KLK8, also known as neuropsin, is one of fifteen members of the human kallikrein-related peptidase (KLK) gene family, which consists of enzymes with serine protease enzymatic activity. Aberrant KLK8 expression has been reported in several malignancies. However, the clinicopathological significance and prognostic value of KLK8 expression in colorectal cancer (CRC) are unknown. Therefore, analysis of public datasets, quantitative real-time PCR and western blot analysis were performed to assess KLK8 expression in CRC at both the mRNA and protein level. KLK8 expression was also assessed by immunohistochemistry in a tissue microarray containing 124 CRC specimens. We observed that KLK8 was overexpressed in CRC tissues and was significantly associated with TNM stage, vascular invasion, differentiation and AJCC stage. Univariate and multivariate Cox analyses confirmed that KLK8 is a significant independent prognostic factor for both DFS and OS. Cell function assays also indicated that KLK8 could facilitate CRC cell proliferation, migration and invasion in vitro. In conclusion, elevated KLK8 expression was correlated with the progression of CRC and is a potential independent prognostic indicator for CRC.

NDRG4 stratifies the prognostic value of body mass index in colorectal cancer

NDRG4 is a novel candidate tumor suppressor and can inhibit PI3K/AKT signal which is related with energy balance and related carcinogenesis. In the present study, we investigated whether NDRG4 status could modify the association of obesity with clinical outcome of colorectal cancer. For this purpose, a hospital-based prospective study cohort of 226 colorectal cancer patients was involved. NDRG4 mRNA levels were determined by real-time PCR. Association of NDRG4 mRNA expression with disease-free and overall survival was studied first. Then, the association of obesity with clinical outcome was determined according to NDRG4 level. Multivariate Cox proportional hazards model was used to compute hazard ratio, adjusting for covariates including microsatellite instability, KRAS, BRAF and PIK3CA mutation. Results showed that NDRG4 mRNA expression was decreased in tumor specimens and significantly correlated with tumor differentiation, invasion and metastasis. Patients with tumor of reduced NDRG4 mRNA level had unfavorable disease-free and overall survival. Obesity was found to be adversely associated with disease-free and overall survival in tumors with reduced NDRG4 level, not in preserved NDRG4 level group, in both univariate and multivariate analysis. These data provided the first evidence that NDRG4 level in colorectal cancer could effectively stratify the prognostic value of obesity, which would better the understanding of the prognostic role of obesity in colorectal cancer. Our results also support the notion that the host-tumor interactions in colorectal cancer might influence tumor aggressiveness.

Secernin-1 contributes to colon cancer progression through enhancing matrix metalloproteinase-2/9 exocytosis

Emerging evidence shows that exocytosis plays a key role in tumor development and metastasis. Secernin-1 (SCRN1) is a novel regulator of exocytosis. Our previous work identified SCRN1 as a tumor-associated gene by bioinformatics analysis of transcriptomes. In this study, we demonstrated the aberrant overexpression of SCRN1 at mRNA and protein level in colon cancer. We also revealed that overexpression of SCRN1 was significantly associated with the tumor development and poor prognosis. Experiments in vitro validated that SCRN1 may promote cancer cell proliferation and secretion of matrix metalloproteinase-2/9 (MMP-2/9) proteins to accelerate tumor progression.

3-L split-dose is superior to 2-L polyethylene glycol in bowel cleansing in Chinese population: a multicenter randomized, controlled trial

Large volume (4 L) of polyethylene glycol (PEG) solution would ensure a better quality of bowel cleansing but might be poorly tolerated. Due to the smaller body size, lower body weight, and different diet habits, the large volume of 4-L PEG might be poorly tolerated by the Chinese population. In view of this, a balance should be made between the volume and effectiveness. This study aimed to compare the effectiveness, compliance, and safety between 3-L split-dose and 2-L PEG in Chinese population. Consecutive patients scheduled for colonoscopy were recruited from 5 tertiary medical centers in South China between April and July, 2014. Patients were prospectively randomized into 2 groups: 3-L split-dose PEG (3L-group) and 2 L PEG (2L-group). The primary endpoint was bowel cleansing and was defined according to Ottawa Bowel Preparation Scale (OBPS). The safety and compliance were also evaluated. A total of 318 patients were included in the analysis. The mean total OBPS score was significantly higher in 2L-group than in 3L-group (4.4 ± 2.7 vs 2.9 ± 2.4, P < 0.001). Both the intention-to-treat and per-protocol analysis found that rates of successful and excellent bowel preparation were much higher in 3L-group (89.9% and 78.0%) than 2L-group (79.2% and 48.4%), respectively (P < 0.001). The average cecum intubation time was significantly shorter in 3L-group (8.2 ± 3.7 min) than in 2L-group (10.3 ± 4.2 min) (P = 0.04). Adenoma detection rate in right colon was slightly higher in 3L-group than in 2L-group (17.6% vs 12.6%, P = 0.21). The safety and compliance including the taste, smell, and dosage of PEG were similar between 2 groups (P > 0.05). 3-L split-dose PEG is superior to 2-L PEG by better bowel cleansing, improved safety and compliance, shorter cecum intubation time, and potentially higher adenoma detection rate in rightward colon in Chinese population.

Zinc-α-2-glycoprotein: a candidate biomarker for colon cancer diagnosis in Chinese population

Zinc-α-2-glycoprotein (AZGP1) is a 41-kDa secreted glycoprotein, which has been detected in several malignancies. The diagnostic value of AZGP1 in serum of prostate and breast cancer patients has been reported. Analyzing “The Cancer Genome Atlas” data, we found that in colon cancer AZGP1 gene expression was upregulated at transcriptional level. We hypothesized that AZGP1 could be used as a diagnostic marker of colon cancer. First, we confirmed AZGP1 expression was higher in a set of 28 tumor tissues than in normal colonic mucosa tissues by real-time quantitative PCR and western blot in a Chinese population. We verified that serum concentration of AZGP1 was higher in 120 colon cancer patients compared with 40 healthy controls by ELISA (p < 0.001). Then receiver-operating characteristic (ROC) curve analysis was used to evaluate the predictive diagnostic value of AZGP1 in serum. The area under the curve (AUC) of AZGP1 was 0.742 (p < 0.001, 95% confidence interval (CI) = 0.656–0.827) in between the AUC of carcinoembryonic antigen (CEA) and the AUC of CA19-9, suggesting that predictive diagnostic value of AZGP1 is between CEA and Carbohydrate 19-9 (CA19-9). The combination of AZGP1 with traditional serum biomarkers, CEA and CA19-9, could result in better diagnostic results. To further validate the diagnostic value of AZGP1, a tissue microarray containing 190 samples of primary colon cancer tissue paired with normal colonic tissue was analysed and the result showed that AZGP1 was significantly upregulated in 68.4% (130 of 190) of the primary cancer lesions. In contrast, there was a weakly positive staining in 29.5% (56 of 190) of the normal colonic tissue samples (p < 0.001). Leave-one-out cross-validation was performed on the serum data, and showed that the diagnostic value of AZGP1 had 63.3% sensitivity and 65.0% specificity. Combination of AZGP1, CEA and CA19-9 had improved diagnosis value accuracy with 74.2% sensitivity and 72.5% specificity. These results suggest that AZGP1 is a useful diagnostic biomarker in tissues and serum from a Chinese population.

Nemo‑like kinase expression predicts poor survival in colorectal cancer

Nemo‑like kinase (NLK), a serine/threonine protein kinase, was previously reported to be associated with tumor proliferation and invasion. The present study aimed to evaluate whether NLK participates in the tumorigenesis and progression of colorectal cancer (CRC). NLK expression was examined using reverse transcription quantitative polymerase chain reaction (RT‑qPCR) and western blot analysis in 50 paired CRC tissues as well as immunohistochemical analysis of 406 cases of primary CRC tissues and paired non‑cancerous tissues. Correlations between NLK expression, the clinicopathological features of CRC patients and clinical outcome were then analyzed. NLK expression was found to be significantly higher in CRC tissues as well as associated with the depth of tumor invasion, lymph node metastasis, distant metastasis, histological differentiation, vascular invasion and advanced tumor stage. Patients with NLK‑positive tumors demonstrated higher rates of recurrence and mortality than patients with NLK‑negative tumors. Multivariate analyses revealed that NLK expression was an independent factor for overall survival [hazard ratio (HR)=0.035; 95% confidence interval (CI)=0.02‑0.19; P<0.001] and disease‑free survival (HR=0.033; 95% CI=0.007‑0.09; P<0.001) in CRC patients. In conclusion, the results of the present study indicated that NLK may serve as a novel biomarker for tumor recurrence and survival for CRC patients.

Cytoreductive surgery plus hyperthermic intraperitoneal chemotherapy improves survival for patients with peritoneal carcinomatosis from colorectal cancer: a phase II study from a Chinese center

Background

Peritoneal carcinomatosis (PC) is a difficult clinical challenge in colorectal cancer (CRC) because conventional treatment modalities could not produce significant survival benefit, which highlights the acute need for new treatment strategies. Our previous case-control study demonstrated the potential survival advantage of cytoreductive surgery (CRS) plus hyperthermic intraperitoneal chemotherapy (HIPEC) over CRS alone. This phase II study was to further investigate the efficacy and adverse events of CRS+HIPEC for Chinese patients with CRC PC.

Methods

A total of 60 consecutive CRC PC patients underwent 63 procedures consisting of CRS+HIPEC and postoperative chemotherapy, all by a designated team focusing on this combined treatment modality. All the clinico-pathological information was systematically integrated into a prospective database. The primary end point was disease-specific overall survival (OS), and the secondary end points were perioperative safety profiles.

Results

By the most recent database update, the median follow-up was 29.9 (range 3.5–108.9) months. The peritoneal cancer index (PCI) ≤20 was in 47.0% of patients, complete cytoreductive surgery (CC0-1) was performed in 53.0% of patients. The median OS was 16.0 (95% confidence interval [CI] 12.2–19.8) months, and the 1-, 2-, 3-, and 5-year survival rates were 70.5%, 34.2%, 22.0% and 22.0%, respectively. Mortality and grades 3 to 5 morbidity rates in postoperative 30 days were 0.0% and 30.2%, respectively. Univariate analysis identified 3 parameters with significant effects on OS: PCI ≤20, CC0-1 and adjuvant chemotherapy over 6 cycles. On multivariate analysis, however, only CC0-1 and adjuvant chemotherapy ≥6 cycles were found to be independent factors for OS benefit.

Discussion

CRS+HIPEC at a specialized treatment center could improve OS for selected CRC PC patients from China, with acceptable perioperative safety.

The association of phosphatase and tensin homolog deleted on chromosome 10 polymorphisms and lifestyle habits with colorectal cancer risk in a Chinese population

The PI3K signaling pathway plays an important role in the development of colorectal cancer (CRC) and other neoplasm. Somatic phosphatase and tensin homolog deleted on chromosome 10 (PTEN) mutations and deletions or epigenetic silencing have been observed in multiple tumor types including CRC. To assess the association of PTEN polymorphisms and lifestyle habits with CRC risk in Chinese population, we carried out a case-control study which included 545 cases and 522 controls. In the present study, we genotyped eight single-nucleotide polymorphisms (SNPs) in PTEN and found that rs11202607 was associated with increased CRC risk (odds ratio (OR) = 1.40, 95 % confidence interval (CI) = 1.04-1.90). Stratification analysis by lifestyle habits showed a stronger association between rs11202607 and CRC risk among never tea drinkers than that among tea-drinkers (OR = 2.04, 95 % CI 1.29-3.22), and significant additive interaction between rs10490920 and tea drinking status was observed. Our study provided the evidence of an association between PTEN polymorphisms and the risk of CRC and significant additive interaction between PTEN polymorphism and tea drinking. Studies with larger sample size and further investigations into the mechanism are warranted to clarify the role of PTEN in colorectal carcinogenesis and the association between PTEN genetic variations, environment exposure, and CRC risk.

Ciz1 is a novel predictor of survival in human colon cancer

Cip1-interacting zinc-finger protein1 (Ciz1) is a nuclear matrix protein associated DNA replication factor which has been implicated in breast and lung cancer progression. However, the clinical significance of Ciz1 expression in colon cancer has not been determined. This study aimed to examine Ciz1 expression pattern and its potential as a biomarker of prognosis in colon cancer. Using quantitative PCR, tissue microarray (TMA), and ELISA, we evaluated Ciz1 mRNA and protein levels in tumor tissues from patients with colon cancer and in paired adjacent normal tissues. Ciz1 mRNA expression was significantly upregulated in 22 of 39 paired samples (P < 0.001). Immunohistochemistry on TMA-containing samples from 203 colon cancer patients indicated that Ciz1 protein expression was significantly higher in tumor tissues than in adjacent normal tissues (Stuart-Maxwell test, P < 0.001). Elevated expression of Ciz1 protein was significantly correlated with T stage (P < 0.001), N stage (P = 0.005), M stage (P = 0.021), and AJCC stage (P = 0.002). Multivariate Cox proportion hazard model analysis revealed that Ciz1 expression is an independent prognostic factor for overall time (OS; hazard ratio (HR): 1.76; 95% confidence interval (CI): 1.04-2.98; P = 0.034) and disease-free survival (DFS; HR: 2.02; 95% CI: 1.14-3.58; P = 0.017) of patients with colon cancer after colectomy. Our data suggested that Ciz1 may be involved in colon cancer progression and could serve as a novel predictor of survival for colon cancer patients.

Up-regulation of CHAF1A, a poor prognostic factor, facilitates cell proliferation of colon cancer

Deregulation of chromatin assembly factor 1, p150 subunit A (CHAF1A) has recently been reported to be involved in the development of some cancer types. In this study, we identified that the frequency of positive CHAF1A staining in primary tumor mucosa (45.8%, 93 of 203 samples) was significantly elevated compared to that in paired normal mucosa (18.7%, 38 of 203 samples). The increased expression was strongly associated with cancer stage, tumor invasion, and histological grade. The five-year survival rate of patients with CHAF1A-positive tumors was remarkably lower than that of patients with CHAF1A-negative tumors. Colon cancer cells with CHAF1A knockdown exhibited decreased cell growth index, reduction in colony formation ability, elevated cell apoptosis rate as well as impaired colon tumorigenicity in nude mice. Hence, CHAF1A upregulation functions as a poor prognostic indicator of colon cancer, potentially contributing to its progression by mediating cancer cell proliferation.

Pediatric colonoscopy in South China: a 12-year experience in a tertiary center

Objective

To investigate: 1) the demographics and clinical characteristics, 2) the findings, and 3) the safety and effectiveness in a cohort of Chinese pediatric patients undergoing colonoscopy.

Methods

The study participants were consecutive patients aged ≤14 years old that underwent their first colonoscopy in the endoscopy center at the First Affiliated Hospital, Sun Yat-sen University between Jan. 1, 2001 and Dec. 31, 2012. Demographic, clinical, endoscopic, and pathological findings were collected.

Results

The cohort consisted of 322 patients, including 218 boys (67.7%) and 104 girls (32.3%). The median age was 8.0 years old and ranged from 9 months to 14 years old. Hematochezia (48.8%) and abdominal pain/discomfort (41.3%) were the most common presentations preceding pediatric colonoscopy. The caecal intubation success rate was 96.3%. No serious complications occurred during the procedures. A total of 227 patients (70.5%) received a positive diagnosis under endoscopy, including 138 patients with polyps and 53 patients with inflammatory bowel disease (IBD). Among the patients with polyps, 71.0% were juvenile polyps. Comparisons between years 2001–2006 and 2007–2012 showed that the IBD detection rate increased significantly (4.6% vs. 22.4%, P<0.001), while the opposite occurred for the polyp detection rate (73.1% vs. 27.6%, P<0.001).

Conclusion

Colonoscopy in pediatric patients is a safe and effective procedure. Polyps are the primary finding during colonoscopy. In South China there has been an increase in pediatric patients diagnosed with IBD over the past decade. However, a large epidemiological study is needed to confirm our findings.

Ubiquitin-like with PHD and ring finger domains 2 is a predictor of survival and a potential therapeutic target in colon cancer

In the present study, we investigated the expression of ubiquitin-like with PHD and ring finger domains 2 (UHRF2) in colon cancer and adjacent normal tissues and estimated the clinicopathological significance and predictive value of UHRF2 expression in colon cancer. Using quantitative real-time PCR, tissue microarray (TMA), western blot analysis and immunohistochemical staining, we evaluated UHRF2 mRNA and protein levels in tumor tissues and paired adjacent normal epithelium. We found that UHRF2 was upregulated at both the transcriptional and translational levels in tumor tissues. Immunohistochemical detection of UHRF2 on a TMA containing 203 paired specimens showed that increased cytoplasmic UHRF2 was significantly associated with clinical stage, depth of invasion, nodal involvement, tumor histologic grade and the presence of metastasis. Patients with UHRF2-positive tumors had a much lower disease-free survival [hazard ratio (HR) 9.511, P<0.001] and overall survival (HR 9.820, P<0.001). Univariate and multivariate analyses were performed to determine the correlation between these parameters and the clinical and pathological variables of the study population verifying that UHRF2 immunoreactivity emerged as an independent prognostic factor in the multivariate analysis. UHRF2 may contribute to the progression of colon carcinogenesis and function as a novel prognostic indicator after curative operation.

Incidence trends and predictors for cost and average lengths of stay in colorectal cancer surgery

AIM: To evaluate the changing trends and outcomes of colorectal cancer (CRC) surgery performed at a large single institution in Taiwan.

METHODS: This study retrospectively analyzed 778 patients who received colorectal cancer surgery at E-Da Hospital in Taiwan from 2004 to 2009. These patients were from health examination, inpatient or emergency settings. The following attributes were analyzed in patients who had undergone CRC surgical procedures: gender, age, source, surgical type, tumor number, tumor size, number of lymph node metastasis, pathologic differentiation, chemotherapy, distant metastases, tumor site, tumor stage, average hospitalization cost and average lengths of stay (ALOS). The odds ratio and 95% confidence intervals were calculated to assess the relative rate of change. Regression models were employed to predict average hospitalization cost and ALOS.

RESULTS: The study sample included 458 (58.87%) males and 320 (41.13%) females with a mean age of 64.53 years (standard deviation, 12.33 years; range, 28-86 years). The principal patient source came from inpatient and emergency room (96.02%). The principal tumor sites were noted at the sigmoid colon (35.73%) and rectum (30.46%). Most patients exhibited a tumor stage of 2 (37.28%) or 3 (34.19%). The number of new CRC surgeries performed per 100000 persons was 12.21 in 2004 and gradually increased to 17.89 in 2009, representing a change of 46.52%. During the same period, the average hospitalization cost and ALOS decreased from $5303 to $4062 and from 19.7 to 14.4 d, respectively. The following factors were associated with considerably decreased hospital resource utilization: age, source, surgical type, tumor size, tumor site, and tumor stage.

CONCLUSION: These results can be generalized to patient populations elsewhere in Taiwan and to other countries with similar patient profiles.

Fms-like tyrosine kinase 3 receptor ligand (Flt3L)-based vaccination administered with an adenoviral vector prevents tumor growth of colorectal cancer in a BALB/c mouse model

PURPOSE

Colorectal cancer is the third most frequent cancer in industrial nations. Therapeutic strategies to treat metastatic disease and prevent recurrence are needed. Anti-tumor immunity can be induced by dendritic cells. Dendritic cells can be expanded by the fms-like tyrosine kinase 3 ligand (Flt3L) in vivo. The aim of this study was to develop an adenoviral-based immune-gene therapy of colorectal cancer with Flt3L in a BALB/c mouse model.

METHODS

A new Flt3L-encoding adenoviral vector (pAdFlt3L) was administered in two approaches in a CT26 colon cancer model in female BALB/c mice. In the therapeutic approach, pAdFlt3L was injected into the tail vein or directly into subcutaneous CT26 colon carcinoma tumors in BALB/c mice. In the vaccination protocol, mice were vaccinated with CT26 cell lysate and pAdFlt3L subcutaneous prior to subcutaneous application of vital CT26 cells.

RESULTS

Application of pAdFlt3L led to high levels of Flt3L in vitro and in vivo. Significant expansion of dendritic cells after application of pAdFlt3L in vivo was confirmed by the use of CD11c and CD11b surface markers in immunohistochemistry and flow cytometry (p = 0.019). In the therapeutic approach, neither intravenous nor intratumoral treatments with pAdFlt3L lead to regression of CT26 tumors. In the vaccination protocol, vaccination completely prevented tumor growth and resulted in superior survival compared to control mice (p < 0.001).

CONCLUSIONS

Our results demonstrate that immunostimulatory therapy with pAdFlt3L is effective to prevent tumor development through vaccination and may represent a therapeutic tool to prevent metastatic disease.

Current status of rectal cancer treatment in China

AIM

Colorectal cancer (CRC) is the fourth most common carcinoma in China. For economic reasons, a national CRC registry has not been established and a large-scale screening programme has not been implemented.

METHOD

Clinical studies (since 2000) of CRC epidemiology which originated from China were summarized, and data was analyzed.

RESULTS

In China, the majority of hospitals in central cities and even in county hospitals are able to provide medical care for CRC patients. Due to socio-economic disparities, medical conditions and skill level, there is a wide variation in the treatment. Most oncologists make their clinical decisions based on the National Comprehensive Cancer Network (NCCN) guidelines, although some domestic guidelines are now available. On 11 October 2011, the China Ministry of Health released national guidelines for CRC treatment. Owing to language difficulties, research on CRC in China has only had a limited exposure in the international literature, due in some part to lack of understanding of the current position in the country.

CONCLUSION

The national guidelines for CRC treatment will give a degree of standardization of the treatment of CRC nationwide and will ensure that higher quality care will be available, especially in rural areas. Chinese colorectal surgeons urgently need to exchange their knowledge and experience with international colleagues.

Up-regulation of tripartite motif-containing 29 promotes cancer cell proliferation and predicts poor survival in colorectal cancer

Tripartite motif-containing 29 (TRIM29), also known as ataxia-telangiectasia group D, is structurally a member of the tripartite motif family of proteins, which characterized by the conserved RING finger, B-box, and coiled-coil domains. TRIM29 functions as an oncogene or a tumor suppressor depending on the tumor types. In this study, we aim to evaluate whether TRIM29 affects the tumorigenesis and progression of colorectal cancer. The expression of TRIM29 was investigated using real-time PCR in 40 pairs of colorectal cancer tissues and immunohistochemistry on a tissue microarray containing 203 cases of primary colorectal cancer paired with non-cancerous tissues. Down-regulation of TRIM29 was achieved by transient transfection in RKO cell lines, and the effects of TRIM29 on tumor proliferation were evaluated by MTT and plate colony formation assays. Results indicated that TRIM29 expression was much higher in colorectal cancer tissues and significantly associated with the depth of tumor invasion, lymph node metastasis, distant metastasis, histological differentiation, vascular invasion, ki-67 index, and advanced tumor stage. Patients with TRIM29-positive tumors had a higher recurrence rate and poorer survival than patients with TRIM29-negative tumors. In multivariate analyses, the TRIM29 expression was an independent factor for determining colorectal cancer prognosis after surgery. Moreover, down-regulation of TRIM29 inhibited tumor cell proliferation in vitro. In conclusion, TRIM29 plays an important role in promoting colorectal cancer progression. Our findings suggest that TRIM29 may serve as a novel biomarker for tumor recurrence and survival for colorectal cancer patients.

Role of endothelin A receptor in colon cancer metastasis: in vitro and in vivo evidence

The endothelin (ET)-1/endothelin A receptor (ETAR) axis is reportedly involved in tumor cell invasion, survival, and metastasis. However, the role of ETAR in colon cancer metastasis and the underlying mechanisms have not been defined. In the present study, we assessed the role of ETAR in colon cancer metastasis in vitro and in vivo. Overexpression and knockdown of ETAR were respectively performed in SW480 and SW620 human colon cancer cells. Overexpression of ETAR in SW480 cells significantly increased cell survival against cisplatin, cell invasion, and matrix metalloproteinase (MMP)-2 expression, which was strengthened by exogenous ET-1 and abolished by selective ETAR antagonist BQ123 and phosphatidylinositol 3-kinase (PI3K) inhibitor LY294002. Knockdown of ETAR in SW620 cells markedly decreased cell survival against cisplatin, cell invasion, and MMP-2 expression, which was strengthened by BQ123 and LY294002, and partially rescued by exogenous ET-1. In a colon cancer liver metastasis mouse model, while ETAR overexpression promoted colon cancer liver metastases, ETAR knockdown markedly decreased liver metastases. In conclusion, our in vitro data demonstrate that ETAR mediates the promoting effects of ET-1 on colon cancer cell survival, invasion and MMP-2 expression by a PI3K-mediated mechanism. Our in vivo data indicate that ETAR markedly promotes colon cancer liver metastasis. This study provides direct evidence for a critical role of ETAR in colon cancer metastasis, which suggests that ETAR antagonism could benefit patients with metastatic colon cancer.

Screening for differentially expressed genes between left- and right-sided colon carcinoma by microarray analysis

Left-sided colon carcinoma (LSCC) and right-sided colon carcinoma (RSCC) differ in their genetic susceptibilities to neoplastic transformation. The present study identified 11 genes that were differentially expressed in LSCC and RSCC by expression profiling with microarray analysis. Compared with RSCC, the human genes for L-lactate dehydrogenase B chain (LDHB), cyclin-dependent kinase 4 inhibitor D (CDKN2D), phosphatidylinositol-4-phosphate-3-kinase C2 domain-containing subunit α (PI3KC2α), protocadherin fat 1 (FAT; a human protein that closely resembles the Drosophila tumor suppressor, fat) and dual specificity protein phosphatase 2 (DUSP2) were upregulated in LSCC. By contrast, genes for ubiquitin D (UBD), casein kinase-1 binding protein (CK1BP), synaptotagmin-13 (SYT1), zinc finger protein 560 (ZNF560), pleckstrin homology domain-containing family B member 2 (PLEKHB2) and IgGFc-binding protein (FCGBP) were downregulated in LSCC compared with RSCC. A quantitative polymerase chain reaction (qPCR) analysis revealed that the mRNA levels of UBD and CK1BP in LSCC were significantly lower compared with those in RSCC (P=0.033 and P= 0.005, respectively), whereas the mRNA levels of LDHB and CDKN2D in LSCC were significantly higher compared with those in RSCC (P=0.008 and P=0.017, respectively). Western blot and immunohistochemical analyses demonstrated that the expression of CDKN2D in LSCC was significantly higher compared with that in RSCC, while the expression of UBD in LSCC was significantly lower compared with that in RSCC. The present study provides important insights into the understanding of the molecular genetic basis for the different biological behaviors observed between LSCC and RSCC. These insights may therefore serve as a basis for the identification of novel colon cancer markers and therapeutic targets.

Cullin 4B is a novel prognostic marker that correlates with colon cancer progression and pathogenesis

Cullin 4B (CUL4B), a scaffold protein of the Cullin4B-RING E3 ligase complex, functions in proteolysis. The present study aims to investigate its expression pattern and evaluate whether CUL4B expression was associated with histopathological and prognosis in the patients with colon cancer. Real-time PCR and western blot were used to identify CUL4B expression in tumor tissue and the paired adjacent normal mucosa from patients with colon cancer. Immunohistochemistry on a tissue microarray containing 203 cases of colon cancer was performed to analyze the association between CUL4B expression and clinicopathological features. Results indicated that CUL4B mRNA and protein levels in tumor tissues were both higher than that in normal mucosae (P < 0.001). Immunohistochemical study displayed that high CUL4B expression was significantly associated with the depth of tumor invasion, lymph node metastasis, distant metastasis, histological differentiation, vascular invasion, and advanced tumor stage. Patients with CUL4B-positive tumors had a higher recurrence rate and poorer survival than patients with CUL4B-negative tumors. In multivariate analyses, CUL4B expression was an independent factor for determining colon cancer prognosis after surgery. In conclusion, CUL4B might promote the progression of colon cancer and can be served as a novel independent prognostic marker for the prediction of recurrence in colon cancer.

Hepatic histopathology and postoperative outcome after preoperative chemotherapy for Chinese patients with colorectal liver metastases

AIM: To assess the effects of preoperative treatment on the hepatic histology of non-tumoral liver and the postoperative outcome.

METHODS: One hundred and six patients underwent hepatic resection for colorectal metastases between 1999 and 2009. The surgical specimens were reviewed with established criteria for diagnosis and grading of pathological hepatic injury. The impact of preoperative therapy on liver injury and postoperative outcome was analyzed.

RESULTS: Fifty-three patients (50%) received surgery alone, whereas 42 patients (39.6%) received neoadjuvant chemotherapy and 11 (10.4%) patients received preoperative hepatic artery infusion (HAI). Chemotherapy included oxaliplatin-based regimens (31.1%) and irinotecan-based regimens (8.5%). On histopathological analysis, 16 patients (15.1%) had steatosis, 31 (29.2%) had sinusoidal dilation and 20 patients (18.9%) had steatohepatitis. Preoperative oxaliplatin was associated with sinusoidal dilation compared with surgery alone (42.4% vs 20.8%, P = 0.03); however, the perioperative complication rate was not significantly different between the oxaliplatin group and surgery group (27.3% vs 13.2%, P = 0.1). HAI was associated with more steatosis, sinusoidal dilation and steatohepatitis than the surgery group, with higher perioperative morbidity (36.4% vs 13.2%, P = 0.06) and mortality (9.1% vs 0% P = 0.02).

CONCLUSION: Preoperative oxaliplatin was associated with sinusoidal dilation compared with surgery alone. However, the preoperative oxaliplatin had no significant impact on perioperative outcomes. HAI can cause pathological changes and tends to increase perioperative morbidity and mortality.

Advances in understanding relationship between miRNA single nucleotide polymorphisms and colorectal cancer

The occurrence and development of colorectal cancer (CRC) are a multifactorial, multi-step evolutionary process. Gene polymorphisms are often involved in tumor development and prognosis. Recent studies have found that certain microRNA (miRNA) single nucleotide polymorphisms were associated with genetic susceptibility to and prognosis of CRC. Understanding the relationship between miRNA single nucleotide polymorphisms and CRC can provide new clues to the detection, prevention, and prognostic evaluation of CRC.

Downregulation of metallothionein 1F, a putative oncosuppressor, by loss of heterozygosity in colon cancer tissue

PURPOSE

Downregulation of metallothionein (MT) genes has been reported in several tumors with discrepant results. This study is to investigate molecular mechanism of MT gene regulation in colon cancer which is characterized by tumor suppressor gene alterations.

EXPERIMENTAL DESIGN

Integral analysis of microarray data with loss of heterozygosity (LOH) information was employed. Quantitative real-time PCR and immunohistochemistry were used to validate MT isoform expression in colon cancer tissues and cell lines. The effects of MT1F expression on RKO cell survival and tumorigenesis was analyzed. Bisulphite sequencing PCR (BSP) and methylation-specific PCR were employed to detect the methylation status of the MT1F gene in colon cancer tissues and cell lines. DNA sequencing was used to examine the LOH at the MT1F locus.

RESULTS

MT1F, MT1G, MT1X, and MT2A gene expression was significantly downregulated in colon cancer tissue (p<0.05). Exogenous MT1F expression increased RKO cell apoptosis and inhibited RKO cell migration, invasion and adhesion as well as in vivo tumorigenicity. Downregulation of MT1F gene in majority of human colon tumor tissues is mainly through mechanism by loss of heterozygosity (p=0.001) while CpG island methylation of MT1F gene promoter region was only observed in poorly differentiated, MSI-positive RKO and LoVo colon cancer cell lines.

CONCLUSIONS

MT1F is a putative tumor suppressor gene in colon carcinogenesis that is downregulated mainly by LOH in colon cancer tissue. Further studies are required to elucidate a possible role for MT1F downregulation in colon cancer initiation and/or progression.

Epidemiological and clinical characteristics of colorectal cancer in Huidong District, Guangdong Province, over the past 10 years

AIM: To analyze the epidemiological and clinical characteristics of colorectal cancer in Huidong District, Guangdong Province, over the past 10 years.

METHODS: Data were collected from all consecutive patients receiving colonoscopy at our hospital during the past 10 years. The epidemiological data, clinical presentations, endoscopic findings, and pathohistological characteristics of patients with colorectal cancer were reviewed and analyzed retrospectively.

RESULTS: A total of 10 532 patients received colonoscopy from 2001 to 2010, and of them 853 cases of colorectal cancer were identified by histological assessment. The detection rate of colorectal cancer rose from 8.0% in the first 5-year period to 8.2% in the second five-year period. The median age of patients with colorectal cancer in the second five-year period was older than that in the first five-year period (65 years vs 59 years). The rectum is the most frequent site for colorectal cancer (55.0%), while hematochezia is the most common symptom (56.0%). The detection rate of right-sided colonic cancer in the second five-year period was significantly higher than that in the first five-year period (19.2% vs 15.1%, P < 0.05). Histologically, adenocarcinoma was the most frequent histological subtype (65.5%).

CONCLUSION: The onset age of patients with colorectal cancer is becoming older in Huidong District, Guangdong Province. The rectum remains the most frequent site for colorectal cancer. The shift in site of colonic cancer toward the right has occurred.

Ubiquitin D is correlated with colon cancer progression and predicts recurrence for stage II-III disease after curative surgery

BACKGROUND

Our recent study observed that the expression of ubiquitin D (UBD), a member of ubiquitin-like modifier family, was upregulated in colon cancer parenchymal cells. The present study further investigated the clinical signicance of UBD in colon cancer.

METHODS

Using quantitative PCR, tissue microarray (TMA), western blot analysis and immunohistochemical stain, we evaluated UBD mRNA and protein levels in tumour tissues from patients with colon cancer at different stages and in paired adjacent normal epithelium.

RESULTS

Immunohistochemical detection of UBD on a TMA containing 203 paired specimens showed that increased cytoplasmic UBD was signicantly associated with depth of cancer invasion, lymph node metastasis, distant metastasis, tumour histologic grade, advanced clinical stage and Ki-67 proliferative index. Patients with UBD-positive tumours had a significantly higher disease recurrence rate and poorer survival than patients with UBD-negative tumours after the radical surgery. Stratification analysis according to tumour stage revealed UBD as an independent predictor for tumour recurrence in patients with stage II and III tumours.

CONCLUSION

UBD may contribute to the progression of colon carcinogenesis and function as a novel prognostic indicator of forecasting recurrence of stage II and III patients after curative operations.

Colorectal cancer in Guangdong Province of China: A demographic and anatomic survey

AIM: To determine the basic demographic features of colorectal cancer (CRC) in five hospitals located in four different areas of Guangdong Province, China.

METHODS: A review of patient records from 1986 to 2006 from five hospitals was conducted. Patient data was obtained, including age, gender, location of lesions, staging and histological type of CRC. The Chi-square test was used to assess differences in rates and a significance level of 0.05 was used. Univariate comparisons were made via Fisher’s exact tests.

RESULTS: Analysis was carried out on 8172 CRC patents, 6.1% (499/8172) of the patients were aged ≤ 30 years. The peak incidence was between the ages 61-70 years (27.8%). The mean age at CRC diagnosis increased from 52 years (1986-1988) to 60 years (2004-2006) and the proportion of young CRC patients decreased from 8.0% to 5.9% over the same period. Of 8172 lesions, 4434 (54.3%) were located in rectum and 3738 (45.7%) in colon. The incidence of rectal cancer decreased significantly from 59.4% (1989-1991) to 51.8% (2004-2006) and right sided colon cancer increased from 40.6% to 48.2%. The mean age, anatomic distribution, histological type and differentiation degree were significantly different among the four geographical areas (P < 0.05).

CONCLUSION: The hospitalization rate for CRC has increased in Guangdong in recent years. The characteristics of CRC from the five hospitals located in the four different areas of Guangdong Province are also different. Further studies are needed to assess more recent trend in the incidence and prevalence of CRC as well as the respective roles of genetic and environmental factors in CRC.