Prognostic Subgroups among Patients with Stage II Colon Cancer

Construction of a potential long noncoding RNA prognostic model involved competitive endogenous RNA for patients with gastric cancer

Increasing evidence has underscored the role of long noncoding RNAs (lncRNAs) make up the major proportion of the competing endogenous RNAs (ceRNAs) network and can regulate gene expression by competitively binding to miRNAs in the development and progression of tumors. Nevertheless, the role of lncRNA-mediated ceRNAs in gastric cancer (GC) and their regulatory mechanisms have not been elucidated to some extent. This study is aimed at constructing a prognostic risk model for GC based on lncRNAs. A TCGA (The Cancer Genome Atlas) dataset was analyzed using edgeR to identify differentially expressed lncRNAs (DElncRNAs) in GC tissues vs normal tissues. Subsequently, DElncRNAs that could predict GC prognosis were determined using a training set. A prognostic risk model based on the DElncRNAs was then constructed. The performance of the model was tested using a test set. The functions of these lncRNAs in GC were investigated using a lncRNA-miRNA-mRNA network. Analysis of lncRNA expression in 407 TCGA GC cases identified 3 lncRNAs that significantly correlated with prognosis. GC cases with high-risk scores showed markedly poor prognosis relative to those with low-risk scores in both the training and test sets. Univariate and multivariate Cox regression analysis of the relationship between various clinical features and prognosis found that these lncRNAs and stage significantly correlated with GC prognosis. A lncRNA-miRNA-mRNA network based on 3 lncRNAs and functional enrichment analysis of interacting mRNA indicated that these genes are enriched in various intracellular receptor signaling pathways, including regulation of muscle system process, and protein deubiquitylation. The current study provides novel insights into the lncRNA-related ceRNA network in GC and sheds lights on underlying 3 lncRNA biomarkers may be independent prognostic signatures in predicting the survival of GC patients.

A Prospective Long-Term Follow-Up Study: The Application of Circulating Tumor Cells Analysis to Guide Adjuvant Therapy in Stage II Colorectal Cancer

BACKGROUND

The efficacy of circulating tumor cells (CTCs) in the selection of stage II colorectal cancer (CRC) patients for adjuvant chemotherapy remains inconclusive.

OBJECTIVE

The aim of this study was to validate the necessity of adjuvant chemotherapy for stage II CRC patients with positive postoperative CTCs.

METHODS

The clinicopathological features and overall survival (OS) of a cohort of 70 patients with confirmed CRC were collected and analyzed.

RESULTS

The total rate of positive CTCs was 55.7%, while the average OS was 70.8 months and the OS rate was 75.7% (53/70). These 70 patients were divided into four subgroups, including a CTC-negative group with non-adjuvant chemotherapy (CHEMO-/CTC-) versus a CTC-positive group with non-adjuvant chemotherapy (CHEMO-/CTC+), CHEMO+/CTC- versus CHEMO+/CTC+, CHEMO-/CTC- versus CHEMO+/CTC-, and CHEMO+/CTC+ versus CHEMO-/CTC+; the total numbers in each subgroup were 25 versus 32, 6 versus 7, 25 versus 6, and 7 versus 32, respectively. The average OS of the CHEMO-/CTC- and CHEMO-/CTC+ groups was 82.0 and 68.1 months, respectively (p = 0.020); the average OS of the CHEMO+/CTC- and CHEMO+/CTC+ groups was 83.6 months and 76.4 months, respectively (p = 0.963); the average OS of the CHEMO-/CTC- and CHEMO+/CTC- groups was 82.0 months and 83.6 months, respectively (p = 0.999); and the average OS of the CHEMO+/CTC+ and CHEMO-/CTC+ groups was 76.4 months and 68.1 months, respectively (p = 0.247).

CONCLUSIONS

Positive CTCs are a potential prognostic marker for stage II CRC.

DNA methylation profile in CpG-depleted regions uncovers a high-risk subtype of early-stage colorectal cancer

BACKGROUND

The current risk stratification system defined by clinicopathological features does not identify the risk of recurrence in early-stage (stage I-II) colorectal cancer (CRC) with sufficient accuracy. We aimed to investigate whether DNA methylation could serve as a novel biomarker for predicting prognosis in early-stage CRC patients.

METHODS

We analyzed the genome-wide methylation status of CpG loci using Infinium MethylationEPIC array run on primary tumor tissues and normal mucosa of early-stage CRC patients to identify potential methylation markers for prognosis. The machine-learning approach was applied to construct a DNA methylation-based prognostic classifier for early-stage CRC (MePEC) using the 4 gene methylation markers FAT3, KAZN, TLE4, and DUSP3. The prognostic value of the classifier was evaluated in 2 independent cohorts (n = 438 and 359, respectively).

RESULTS

The comprehensive analysis identified an epigenetic subtype with high risk of recurrence based on a group of CpG loci in the CpG-depleted region. In multivariable analysis, the MePEC classifier was independently and statistically significantly associated with time to recurrence in validation cohort 1 (hazard ratio = 2.35, 95% confidence interval = 1.47 to 3.76, P < .001) and cohort 2 (hazard ratio = 3.20, 95% confidence interval = 1.92 to 5.33, P < .001). All results were further confirmed after each cohort was stratified by clinicopathological variables and molecular subtypes.

CONCLUSIONS

We demonstrated the prognostic statistical significance of a DNA methylation profile in the CpG-depleted region, which may serve as a valuable source for tumor biomarkers. MePEC could identify an epigenetic subtype with high risk of recurrence and improve the prognostic accuracy of current clinical variables in early-stage CRC.

The clinical value of a nomogram constructed from CEA, CA199, PT, FIB, tumor differentiation and TNM stage in colorectal cancer

BACKGROUND

The accurate Tumor-Node-Metastasis (TNM) staging of colorectal cancer (CRC) is of great guiding significance for the judgment of tumor progression and prognosis, and the formulation of treatment strategies.

OBJECTIVE

The aim of this study was to construct a recurrence risk scoring (RRS) system and prognostic prediction model to improve the accuracy of staging, prognosis prediction, and clinical decision making in resectable CRC.

METHODS

CRC patients who underwent radical resection were retrospectively enrolled into study. Multivariable Cox regression model was applied to screen for independent prognostic factors. The RRS system is composed of independent prognostic factors which was awarded 1point each. A prognostic model composed of RRS and TNM staging system (RRS-TNM model) was applied to predict postoperative recurrence.

RESULTS

TNM stage, tumor differentiation, preoperative elevated Carcinoembryonic Antigen, Carbohydrate Antigen 199, Prothrombin Time and Fibrinogen were the independent prognostic biomarkers. 173 of 540 patients had recurrence. The 5-year cumulative recurrence rate (5-y CRR) and disease-free survival (DFS) of postoperative p-TNM stage I, II, and III were 12.7% and 104.8 months, 26.5% and 89.3 months, and 55.5% and 57.3 months, respectively. The 5-y CRR and DFS of preoperative Low-risk (RRS 0-1score), Middle-risk (RRS 2-3scores), and High-risk (RRS 4-5scores) groups were 13.9% and 101.1 months, 40.9% and 75.5 months, and 70.2% and 41.1 months. The AUC (area under ROC curve) of RRS system was not inferior to that of TNM staging system (0.713 vs. 0.666; P= 0.093). The AUC (0.770) and C-index value (0.721) of RRS-TNM model were significantly better than both RRS and TNM staging system (P< 0.001).

CONCLUSIONS

The RRS system accurately identifies CRC patients with high-risk recurrence preoperatively. Constructing a nomogram using the RRS system and TNM staging significantly improves the accuracy of staging and prognosis prediction, which is of great clinical significance for individualized clinical treatment and follow-up of CRC.

Prognostic Value of Lymph Node Evaluation in Stage II Small Bowel Adenocarcinoma: An Updated Analysis of Surveillance, Epidemiology, and End Results Database

Background

Due to the lack of large-scale clinical trials, the treatment strategies of small bowel adenocarcinoma (SBA) are controversial, especially for stage II patients. According to the National Comprehensive Cancer Network (NCCN) guideline, few lymph nodes (LNs) examined (<5 for duodenum or <8 for jejunal/ileal primary location) are one of the high-risk features for stage II patients, for whom adjuvant chemotherapy is recommended. This consensus is originally drawn from data in the Surveillance, Epidemiology, and End Results Database (SEER) between 1988 and 2010. However, the surgical modalities and chemotherapy strategies changed a lot after 2004 for SBA patients. The previous data may not represent a true picture of current therapeutics. Thus, we reanalyzed the SEER database and updated the cutoff point of LN numbers resected with respect to cancer-specific survival (CSS) using the latest SEER information.

Methods

Patients diagnosed with stage II SBA and who underwent curative surgery between 2004 and 2018 were extracted from the SEER database. CSS was calculated using the Kaplan–Meier method and compared by log-rank test. Maximum survival differences based on total LNs examined for duodenal and jejunoileal tumors were determined separately with the cut-point analysis and maximum log-rank χ² statistic. A nomogram model was constructed based on the multivariate Cox analysis to predict 5‐ and 10‐year CSS and was then validated with an internal cohort.

Results

A total of 935 stage II SBA patients met the inclusion criteria. The greatest difference in survival was found in patients who had removal of at least 5 LNs for duodenal and 12 LNs for jejunoileal tumors. Multivariate Cox analysis showed that age, T stage, histology grade, primary site, and LN numbers were independent prognostic factors for survival. The C index of nomogram model was 0.701 (95% CI, 0.661–0.741, p < 0.001).

Conclusions

The number of LNs harvested is an important prognostic factor for survival in stage II SBA patients. LN number examined <5 remains a high-risk factor for duodenum, but the cutoff point for jejunal/ileal tumors should rise from 8 to 12. Appropriate radical lymphadenectomy should be performed in stage II SBA surgery.

Prothrombin time (PT) and CEA as prognostic predictive biomarkers for postoperative recurrence after curative resection in patients with stage I-III colorectal cancer: a retrospective cohort study

There are no ideal biomarkers including the TNM stage that can accurately predict the recurrence of colorectal cancer (CRC) and the benefit of chemotherapy for stage II patients. Here, 451 CRC patients were divided into three groups according to preoperative levels of prothrombin time (PT) and CEA to analyze the value of these indexes in predicting postoperative recurrence in different TNM stages. Preoperatively elevated levels of PT and CEA were significantly associated with a high 5-year cumulative recurrence rate (CRR) and short recurrence-free survival (RFS). According to PT and CEA levels, the 5-year CRR and RFS differed significantly among the High-risk (PT ≥ 12.65 s and CEA ≥ 10.175 ng/ml), Middle-risk (PT ≥ 12.65 s or CEA ≥ 10.175 ng/ml), and Low-risk (PT < 12.65 s and CEA < 10.175 ng/ml) groups (p < 0.001). In the same TNM stage, the 5-year CRR of the High-risk group was significantly higher and the RFS was markedly shorter than those in the Low-risk and even those in stage III (p < 0.001). In the subgroup of early stage (stage I and II), the 5-year CRR of the High-risk group was significantly higher and the RFS was significantly shorter than those in stage IIIA and IIIB (p < 0.001), which is similar to IIIC. In conclusion, preoperatively elevated levels of serum PT and CEA were reliable predictors of postoperative high-risk recurrence in CRC and combined with TNM stage precisely identify postoperative recurrence CRC patients in stage I-III and the benefit of adjuvant chemotherapy for patients with stage II CRC.

Nestin and CD34 expression in colorectal cancer predicts improved overall survival

BACKGROUND

Nestin, a class VI intermediate filament protein of the cytoskeleton, and CD34, a transmembrane phosphoglycoprotein, are markers of progenitor cells. This study aimed to evaluate their expression and clinical significance in colorectal cancer.

METHODS

A clinically annotated tissue microarray, including 599 patients with colorectal cancer, was analyzed by immunohistochemistry. Furthermore, nestin and CD34 correlations with HIF-1a and a panel of cytokines and chemokines were assessed using quantitative reverse transcription PCR and The Cancer Genome Atlas dataset.

RESULTS

Expression of nestin and CD34 was observed only in the tumor stroma. Patients displaying high expression of nestin and CD34 demonstrated higher rates of T1 and T2 tumors (p = .020), lower vascular invasion (p < .001) and improved 5-year overall survival (65%; 95% CI = 55-73 vs 45%; 95% CI = 37-53) after adjusting for clinicopathological characteristics (HR: 0.67; 95% CI = 0.46-0.96). A moderate to strong correlation (r = 0.37-0.78, p < .03) of nestin and CD34 was demonstrated for the following markers; HIF-1α, CD4, CD8, FOXP3, IRF1, GATA3, CCL2, CCL3, CXCL12 and CCL21.

CONCLUSIONS

Combined expression of nestin and CD34 expression is associated with better overall survival possibly by modulating a favorable immune response.

MAP17 Expression in Colorectal Cancer Is a Prognostic Factor for Disease Recurrence and Dismal Prognosis Already in Early Stage Disease

BACKGROUND

Disease recurrence in colorectal cancer constitutes a major cause of significant cancer-associated morbidity and mortality. MAP17 is a small protein, and its overexpression in malignant tumors has been correlated with aggressive tumor phenotypes. The aim of the present study was to investigate the expression patterns of MAP17 in colorectal cancer specimens and to assess its clinical significance.

PATIENTS AND METHODS

Surgical specimens of 111 patients with primary resectable colorectal cancer constituted the study population. Expression of MAP17 was assessed by immunohistochemistry, and the results were correlated with clinical and survival data.

RESULTS

MAP17 was expressed in cancer cells and endothelial cells of tumor blood vessels. Expression of MAP17 more than 10% was correlated with advanced disease stage (p < 0.001), higher T classification (p = 0.007), the presence of lymph node metastasis (p < 0.001), vascular (p = 0.013) and perineural invasion (p = 0.012). Patients exhibiting MAP17 expression of more than 30% in cancer cells compared to those expressing MAP17 less than 10% demonstrated a significantly worse 3-year progression-free survival (35.2 vs. 91%, p < 0.001) and 5-year overall survival (40.8 vs. 91%, p < 0.001). Cox regression analysis confirmed MAP17 expression of more than 30% as a prognostic marker of progression free survival (HR 0.136, 95% CI = 0.056-0.329, p < 0.001) and overall survival (HR 0.144 [95% CI) = 0.049-0.419, p < 0.001) independent of other clinicopathological characteristics. Statistically significantly worse 3-year progression-free survival and 5-year overall survival was demonstrated in the subgroup analysis of patients with early stage cancer only and high expression of MAP17.

CONCLUSIONS

High MAP17 expression in patients with colorectal cancer is a significant risk factor for cancer-associated morbidity and mortality already in early stage disease.

High fascin-1 expression in colorectal cancer identifies patients at high risk for early disease recurrence and associated mortality

BACKGROUND

Fascin is the main actin cross-linker protein that regulates adhesion dynamics and stabilizes cell protrusion, such as filopodia. In human cancer, fascin expression correlates with aggressive clinical features. This study aimed to determine the expression patterns of fascin-1 and assessed its prognostic significance in colorectal cancer.

METHODS

One hundred eleven specimens of patients with primary resectable colorectal cancer were examined via immunohistochemistry for the expression of fascin-1, and the results were correlated with clinicopathological characteristics and survival data.

RESULTS

Fascin-1 staining displayed strong intensity in the cytoplasm of the colorectal cancer cells and endothelial cells of tumor blood vessels. Moderate to high fascin-1 expression was associated with progressive anatomic disease extent (p < 0.001), higher T classification (p = 0.007), the presence of lymph node (p < 0.001) and distant metastasis (p = 0.002), high grade tumors (p = 0.002) and vascular invasion (p < 0.001). Patients displaying moderate and high fascin-1 expression demonstrated a significantly worse 5-year overall survival [HR; 3.906, (95%CI) = 1.250-12.195] and significantly worse 3-year progression-free survival [HR; 3.448, (95%CI) = 1.401-8.475] independent of other clinicopathological characteristics. Besides, high fascin-1 expression in early-stage cancer only was associated with a dismal prognosis.

CONCLUSIONS

High fascin-1 expression in colorectal cancer is an independent negative prognostic factor for survival, increasing the risk for disease recurrence or death almost by sevenfold. Fascin-1 expression could be potentially utilized to identify high-risk patients prone to metastasis already in early-stage disease.

Better survival of right-sided than left-sided stage II colon cancer: a propensity scores matching analysis based on SEER database

BACKGROUND/AIMS

Most studies have found that right-sided colon cancer (RCC) has worse prognosis than left-sided colon cancer (LCC), especially in stage III, but the reported prognosis of stage II colon cancer is variable. This study aimed to evaluate the impact of tumor location on survival outcomes in stage II colon cancer.

MATERIALS AND METHODS

Patients with stage II colon cancer were identified in the Surveillance, Epidemiology, and End Results database from 2004 to 2009. The effect of tumor location on overall survival and cancer-specific survival was analyzed using Cox proportional hazards regression models and propensity score matching.

RESULTS

Of 16,519 patients, 69.6% had RCC and30.4% had LCC. In unadjusted analyses, RCC had a 13% increased overall mortality risk (hazards ratio [HR], 1.13; 95% confidence interval [CI], 1.07-1.19; p<0.001) but an18% reduction in cancer-specific mortality risk compared with LCC (HR, 0.82; 95% CI, 0.76-0.89; p<0.001). After propensity scores matching analyses, RCC had a 21% reduced overall mortality risk (HR, 0.79; 95% CI, 0.72-0.87; p<0.001) and a 49% reduction in cancer-specific mortality risk compared with LCC (HR, 0.51; 95% CI, 0.44-0.60; p<0.001).

CONCLUSION

When adjusted for multiple clinicopathological features, stage II RCC showed better prognosis than stage II LCC.

GLUT3 induced by AMPK/CREB1 axis is key for withstanding energy stress and augments the efficacy of current colorectal cancer therapies

Cancer cells are usually characterized by hyperactive glucose metabolism, which can often lead to glucose scarcity; thus, alternative pathways to rewire cancer metabolism are required. Here, we demonstrated that GLUT3 was highly expressed in colorectal cancer (CRC) and negatively linked to CRC patient outcomes, whereas GLUT1 was not associated with CRC prognosis. Under glucose-limiting conditions, GLUT3 expedited CRC cell growth by accelerating glucose input and fuelling nucleotide synthesis. Notably, GLUT3 had a greater impact on cell growth than GLUT1 under glucose-limiting stress. Mechanistically, low-glucose stress dramatically upregulated GLUT3 via the AMPK/CREB1 pathway. Furthermore, high GLUT3 expression remarkably increased the sensitivity of CRC cells to treatment with vitamin C and vitamin C-containing regimens. Together, the results of this study highlight the importance of the AMPK/CREB1/GLUT3 pathway for CRC cells to withstand glucose-limiting stress and underscore the therapeutic potential of vitamin C in CRC with high GLUT3 expression.

MicroRNA-421 Inhibits Apoptosis by Downregulating Caspase-3 in Human Colorectal Cancer

Purpose

Dysregulated microRNAs (miRNAs/miRs) have been reported to play significant roles in pathogenesis of colorectal cancer (CRC). Previous studies have demonstrated that miR-421 regulates apoptosis in some cancers. Caspase-3 plays a key role in apoptosis, but the relationship between miR-421 and caspase-3 in CRC has not been determined. In this study, we investigated the role of miR-421 in CRC and the relationship between miR-421 and caspase-3.

Methods

Expression of miR-421 and caspase-3 were detected in human paired CRC cancer tissues and corresponding paracancerous tissues. In situ detection of tissue, apoptosis was performed via the TUNEL assay. HCT116 and SW480 cell lines were subjected to several in vitro experiments to explore the relationship between miRNA421 and caspase-3 during apoptosis using miR421 mimics/antagomir and luciferase reporter assay. Apoptosis was measured by determining the levels and activity of caspase-3 as well as DNA fragmentation. Luciferase reporter assay was performed to determine the potential interaction of miR-421 with caspase-3.

Results

The results showed that the expression of miR-421 in cancer tissues was higher than that in corresponding paracancerous tissues. Inhibition of miR-421 induced apoptosis, as shown by the upregulation of caspase-3 activity and expression as well as DNA fragmentation, which were attenuated by miR-421 mimic. We further showed that miR-421 targeted and inhibited CASP3 expression by targeting sites located in the 3ʹ-untranslated region (3ʹ-UTR) of CASP3 mRNA.

Conclusion

This study demonstrated an anti-apoptotic role of miR-421 in CRC and identified caspase-3 gene as a direct target of miR-421. These findings provide a potential treatment strategy using miR-421 as a therapeutic target for CRC.

Transcriptome analysis reveals a reprogramming energy metabolism-related signature to improve prognosis in colon cancer

Although much progress has been made to improve treatment, colon cancer remains a leading cause of cancer death worldwide. Metabolic reprogramming is a significant ability of cancer cells to ensure the necessary energy supply in uncontrolled proliferation. Since reprogramming energy metabolism has emerged as a new hallmark of cancer cells, accumulating evidences have suggested that metabolism-related genes may serve as key regulators of tumorigenesis and potential biomarkers. In this study, we analyzed a set of reprogramming energy metabolism-related genes by transcriptome analysis in colon cancer and revealed a five-gene signature that could significantly predict the overall survival. The reprogramming energy metabolism-related signature could distinguish patients into high-risk and low-risk groups with significantly different survival times (P = 0.0011; HR = 1.92; 95% CI [1.29–2.87]). Its prognostic value was confirmed in another two independent colon cancer cohorts (P = 5.2e–04; HR = 2.09, 95%; CI [1.37–3.2] for GSE17538 and P = 3.8e−04; HR = 2.08, 95% CI [1.37–3.16] for GSE41258). By multivariable analysis, we found that the signature was independent of clinicopathological features. Its power in promoting risk stratification of the current clinical stage was then evaluated by stratified analysis. Moreover, the signature could improve the power of the TNM stage for the prediction of overall survival and could be used in patients who received adjuvant chemotherapy. Overall, our results demonstrated the important role of the reprogramming energy metabolism-related signature in promoting stratification of high-risk patients, which could be diagnostic of adjuvant therapy benefit.

Prognostic value of a hypoxia-related microRNA signature in patients with colorectal cancer

Hypoxia has been particularly associated with poor prognosis in cancer patients. Recent studies have suggested that hypoxia-related miRNAs play a critical role in various cancers, including colorectal cancer (CRC). In the present study, we found 52 differentially expressed miRNAs in HT-29 cells under hypoxic conditions versus normoxic conditions by analyzing the profiles of miRNAs. Using Cox model, we developed a hypoxia-related miRNA signature consisting of four miRNAs, which could successfully discriminate high-risk patients in the Cancer Genome Atlas (TCGA) training cohort (n=381). The prognostic value of this signature was further confirmed in the TCGA testing cohort (n=190) and an independent validation cohort composed of formalin-fixed paraffin-embedded clinical CRC samples (n=220), respectively. Multivariable Cox regression and stratified survival analysis revealed this signature was an independent prognostic factor for CRC patients. Time-dependent receiver operating characteristic (ROC) analysis showed that the area under the curve (AUC) of this signature was significantly larger than that of any other clinical risk factors or single miRNA alone. A nomogram was constructed for clinical use, which incorporated both the miRNA signature and clinical risk factors and performed well in the calibration plots. Collectively, this novel hypoxia-related miRNA signature was an independent prognostic factor, and it possessed a stronger predictive power in identifying high-risk CRC patients than currently used clinicopathological features.

L1CAM expression in colorectal cancer identifies a high-risk group of patients with dismal prognosis already in early-stage disease

Background: Metastatic disease in colorectal cancer represents a major cause of significant cancer-associated morbidity and mortality. L1CAM is a stem cell marker, cell adhesion molecule, belongs to the immunoglobulin superfamily of cell adhesion molecules (IgCAM) and it is aberrantly expressed in several different types of human solid tumors. The aim of the present study was to assess the expression patterns of L1CAM and its clinical significance in colorectal cancer.Patients and methods: Surgical specimens of 109 patients with primary resectable colorectal cancer were examined for L1CAM expression via immunohistochemistry and the results were correlated with clinical and survival data.Results: L1CAM expression was significantly correlated with advanced stage of disease (p < .001), higher T classification (p = .040), the presence of lymph node (p < .001) and distant metastasis (p = .011). Patients displaying high L1CAM expression demonstrated a dismal three-year progression free survival (29.7% vs 87.1%, p < .001) and five-year overall survival (39.9% vs 87.7%, p < .001). Multivariate analysis using Cox proportional hazard models revealed high L1CAM expression as a prognostic marker of dismal progression free (HR 0.187, 95%CI = 0.075-0.467, p < .0001) and overall survival (HR 0.154, 95%CI = 0.049-0.483, p = .001) independent of other clinicopathological characteristics. Subgroup analysis comprised of patients with early stage disease only presented as well significantly worse progression free and overall survival when L1CAM exhibited high expression.Conclusions: Colorectal cancer patients displaying high expression of L1CAM harbor high risk for metastasis already in early stage disease identifying therefore a group of patients prone to dismal prognosis.

Gut butyrate-producing organisms correlate to Placenta Specific 8 protein: Importance to colorectal cancer progression

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Genes from stools have molecular significance with CRC tumorgenesis.

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SCFAs, the metabolites of microbiota, can suppress CRC tumorigenesis.

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Relationship between colonic genes, gut microbiota, or their metabolites is significant.

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Changes of PLAC8 and butyrate-producing organisms were found in stools of CRC patients.

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Butyrate can reduce the CRC formation through regulating PLAC8 expression.

Tumor metastasis or recurrence often occurs in patients with curative resection of colorectal cancer (CRC). Placental-specific 8 (PLAC8), which has increased expression in stool, may be associated with CRC recurrence. Insights into the role of PLAC8 in CRC recurrence and its clinical significance may support to develop strategies for preventing CRC recurrence and deterioration. Clinical tissues, cell and animal models were used to clarify the roles of PLAC8 in CRC tumorigenesis, invasion, and migration. Next-generation sequencing of 16S ribosomal DNA has been used to assess the gut microbiota in stool of CRC patients. We found that PLAC8 was upregulated in tissues from patients with late-stage CRC. In our in vitro studies, PLAC8 was dynamically regulated in mitotic cells. Overexpressed PLAC8 was nucleated at the centrosome during mitosis, and therefore, PLAC8 overexpression might increase cell growth and migration (all p < 0.05). The tumorigenic and invasive effects of PLAC8 on CRC cells were also confirmed in a xenograft mouse model. We further identified reduced levels of two butyrate-producing organisms, Butyricicoccus and Prevotella spp., in stools from CRC patients. We found that butyrate downregulated PLAC8 expression and induced apoptosis in PLAC8-overexpressing cells. Our data suggests that PLAC8 gene and protein expression and dysbiosis of gut microflora, especially in butyrate-producing microorganisms, may be indicators of CRC progression.

CDX2 and Muc2 immunohistochemistry as prognostic markers in stage II colon cancer

The treatment for colorectal cancer is largely surgical followed by adjuvant chemotherapy in high-risk cases. In patients with stage II cancer, there is no clear benefit for chemotherapy, and the current tools for assessment of risk are inadequate. A recent study identified that colorectal cancer with a gene signature similar to undifferentiated colonic stem cells was associated with a worse outcome. It was later shown that loss of CDX2 detected by immunohistochemistry (IHC) alone resulted in a worse prognosis and that this could be used to predict patients who would benefit from chemotherapy. Having observed that CDX2 expression can be patchy, we elected to validate these prior results for clinical practice using whole-slide IHC. The pathology of all cases was reviewed, and 3 blocks were selected for CDX2 IHC. We also expanded the panel beyond CDX2 to assess whether other markers in the gene signature including CDX1, Muc2, GPX2, and villin could better predict outcome. Among 210 cases, CDX2 expression was diffusely lost in 11% and focally lost in 23% of cases. There was no difference in survival based on CDX2 expression, but Muc2 loss was associated with reduced survival (hazard ratio, 3.32; 95% confidence interval, 1.20 to 9.20). No significant differences in outcome were identified based on CDX1, GPX2, or villin expression. In keeping with this, assessment of The Cancer Genome Atlas gene expression data demonstrated that decreased Muc2 expression was associated with reduced overall survival. Our results with whole-slide IHC are different from the previous studies and caution against the use of CDX2 in isolation as a prognostic marker in clinical practice. We have identified that loss of Muc2 is associated with reduced survival. This supports the use of the colonic differentiation gene expression signature to identify high-risk patients but cautions against the use of any one IHC-based marker in isolation.

Genome-wide DNA methylation analysis reveals a prognostic classifier for non-metastatic colorectal cancer (ProMCol classifier)

OBJECTIVE

Pathological staging used for the prediction of patient survival in colorectal cancer (CRC) provides only limited information.

DESIGN

Here, a genome-wide study of DNA methylation was conducted for two cohorts of patients with non-metastatic CRC (screening cohort (n=572) and validation cohort (n=274)). A variable screening for prognostic CpG sites was performed in the screening cohort using marginal testing based on a Cox model and subsequent adjustment of the p-values via independent hypothesis weighting using the methylation difference between 34 pairs of tumour and normal mucosa tissue as auxiliary covariate. From the 1000 CpG sites with the smallest adjusted p-value, 20 CpG sites with the smallest Brier score for overall survival (OS) were selected. Applying principal component analysis, we derived a prognostic methylation-based classifier for patients with non-metastatic CRC (ProMCol classifier).

RESULTS

This classifier was associated with OS in the screening (HR 0.51, 95% CI 0.41 to 0.63, p=6.2E-10) and the validation cohort (HR 0.61, 95% CI 0.45 to 0.82, p=0.001). The independent validation of the ProMCol classifier revealed a reduction of the prediction error for 3-year OS from 0.127, calculated only with standard clinical variables, to 0.120 combining the clinical variables with the classifier and for 4-year OS from 0.153 to 0.140. All results were confirmed for disease-specific survival.

CONCLUSION

The ProMCol classifier could improve the prognostic accuracy for patients with non-metastatic CRC.

Macroscopic serosal invasion and small tumor size as independent prognostic factors in stage IIA colon cancer

BACKGROUND

This study aimed to investigate the prognostic factors of patients with stage IIA (T3N0M0) colon cancer in terms of macroscopic serosal invasion and small tumor size.

METHODS

We enrolled 375 stage IIA colon cancer patients who underwent curative resection between January 2004 and December 2011. Macroscopic serosal invasion was defined as tumor nodules or colloid changes protruding the surface of the serosa. The clinicopathologic characteristics were analyzed to identify independent prognostic factors.

RESULTS

The median follow-up was 47 months (range, 1-90 months). On multivariate survival analysis, macroscopic serosal invasion (adjusted hazard ratio [HR] = 4.750; p = 0.013), tumor size < 5 cm (adjusted HR = 3.112, p = 0.009), perineural invasion (adjusted HR = 3.528; p = 0.002), < 12 retrieved lymph nodes (adjusted HR = 4.257; p = 0.002), and localized perforation (adjusted HR = 7.666; p = 0.008) were independent risk factors for recurrence.

CONCLUSION

We found novel prognostic factors of stage IIA colon cancer, including macroscopic serosal invasion and small tumor size (< 5 cm). Further studies are needed to evaluate the benefit of adjuvant chemotherapy in patients with these prognostic factors.

Prognostic value of multiple cytokine analysis in colorectal cancer: a systematic review

The link between inflammation and outcome has been established in colorectal cancer through experimental evidence demonstrating an influential role of pro-inflammatory cytokines on tumour growth and progression. Furthermore, prognostic scores based on overall markers of systemic inflammation such as C-reactive protein and neutrophil count have been validated. Over recent years, an increasing number of inflammatory cytokines have been identified as prognostic predictors in colorectal cancer and the aim of this review was to evaluate the literature on the prognostic value of multiple cytokine measurement. The English language literature published since the year 2000 was searched using terms including, 'colorectal cancer', 'cytokines' and 'prognosis' through Medline, Embase and Scopus databases. Reports were screened by two independent reviewers and studies evaluating fewer than three cytokines were excluded. Quality assessments were performed in six domains before data extraction was undertaken in duplicate. Seven studies were found to evaluate multiple cytokines after 570 records were screened. The quality of these studies ranged from poor to moderate and were heterogeneous in terms of the patient population and the number and selection of cytokines tested. Four studies combined multiple cytokine levels into a single score and found them to be predictive of prognosis whereas the association between individual cytokines and outcome was not demonstrated consistently. The combination of multiple cytokine markers into a single prognostic score shows promise in colorectal cancer and further research is required to establish and validate such a score.

Homeobox protein CDX2 as a prognostic biomarker in solid malignancies: a meta-analysis

Background

CDX2 is a caudal-homeobox gene and its expression is abnormal in numerous tumour cell types. Nevertheless, its prognostic value for solid tumours requires further investigation. Hence, we conducted a meta-analysis to determine the significance of CDX2 as a prognostic biomarker in solid malignancies systematically.

Materials and Methods

We performed a systematic literature search in PUBMED and EMBASE up to May 2017. Retrospective studies comparing the prognostic value of different CDX2 levels in human malignancies were included. Data extractions and methodological assessments were performed separately by two investigators using a standard procedure. The statistical procedures were performed using Review Manager 5.3 and STATA/MP 14.0.

Results

A total of 26 retrospective studies met the inclusion criteria and comprised 5008 participants. Patients with CDX2 overexpression had significantly better 3-year, 5-year, 10-year and disease-free survival outcomes in solid malignancies, regardless of the cancer type, mean age, and source region. Nevertheless, there was no significant difference in the patients from Europe. The expression level of CDX2 was not statistically associated with cancer relapse. Moreover, our analysis showed that CDX2 overexpression is correlated to better responses to chemotherapy in patients with TNM IV stage cancers. The stability of the pooled outcomes was verified by sensitivity analysis. The funnel plots, Egger's test and Begg's test jointly confirmed that there was no publication bias.

Conclusions

Overexpression of CDX2 is a reliable biomarker of a better prognosis in solid malignancies.

Stromal Expression of Vimentin Predicts the Clinical Outcome of Stage II Colorectal Cancer for High-Risk Patients

Background

Increased expression of vimentin in tissue samples from patients with colorectal cancer (CRC) has been previously demonstrated, but its prognostic significance remains controversial, and the clinical significance for patients with stage II CRC is still unknown. The aim of this study was to evaluate the expression of vimentin in CRC and its potential prognostic significance.

Material/Methods

We analyzed vimentin expression in 203 CRC tissue samples from patients with stage II cancer using immunohistochemistry, and correlated the findings with clinicopathological patient features. CRC-specific survival (CSS) and disease-free survival (DFS) were analyzed using the Kaplan-Meier method. Univariate and multivariate analysis was performed using the Cox proportional hazards method for survival.

Results

Vimentin expression was significantly correlated only with tumor (T) stage (p=0.024). Kaplan-Meier survival analysis indicated that vimentin expression could stratify the CSS and DFS of patients with stage II CRC at high risk (p=0.029, p=0.042, respectively), but not those of low-risk stage II patients (p=0.208, p=0.361, respectively). Univariate and multivariate analysis further revealed that stromal vimentin expression is an independent prognostic factor for CSS and DFS of high-risk stage II patients (p=0.043, p=0.022, respectively). Moreover, high-risk stage II patients with low stromal vimentin expression benefitted more from standard adjuvant chemotherapy than those with high stromal vimentin expression (CSS: p=0.012 vs. p=0.407; DFS: p=0.017 vs. p=0.420).

Conclusions

Our study suggests that stromal vimentin expression is a promising indicator for survival prediction and adjuvant chemotherapy response in patients with stage II CRC with high-risk factors for recurrence.

The prognostic yield of biomarkers harvested in chemotherapy-naive stage II colon cancer: can we separate the wheat from the chaff?

The TNM-system fails to accurately predict disease recurrence in a considerate number of patients. While node-negative (stage II) colon cancer is considered to have an overall good prognosis, the 5-year cancer-specific survival is reported at 81-83% in patients who did not have adjuvant chemotherapy. Thus, reliance on node-status alone has lead to under-treatment in a subgroup of stage II patients with an unfavorable prognosis. The search for new and better prognosticators in stage II colon cancer has suggested several proposed biomarkers of better prognostication and prediction. However, few such biomarkers have reached widespread clinical utility. For the clinician swimming in the sea of emerging biomarkers, it may be hard to recognize the true floating aid from the surrounding debris in the search for more precise decision-making. Proposed markers include microsatellite instability (MSI), KRAS mutations and BRAF mutations, but a number of gene panels and consensus molecular subtypes are proposed for clinical prediction and prognostication as well. While several studies suggest such biomarkers or panels to have a prognostic role in subgroups of patients, a number of studies are reported in heterogeneous groups with in part discordant findings, which again distorts the predictive and prognostic ability of each marker. Lack of homogeneous cohorts, underpowered studies in strict subgroups and challenges in analytical and clinical validity may hamper the progress towards widespread clinical utility. The harvest of prognostic biomarkers in colon cancer has yielded a huge number of candidates for which it is now time to separate the wheat from the chaff.