Small Bowel Obstruction Caused by Migration of Fractured Metal Stent in Patients with Malignant Gastric Outlet Obstruction: A Report of Two Cases and Review of the Literature

Gastroduodenal stenting (GDS) is a less invasive alternative to gastrojejunostomy for the management of malignant gastric outlet obstruction (mGOO). GDS is a minimally invasive treatment with good technical and clinical success, and severe complications that require surgical intervention are rare. Stent fracture is an uncommon complication associated with GDS; however, migration of the fractured distal segment can result in small bowel obstruction. Adverse effects of stent fractures in patients with mGOO have rarely been reported. We herein report two surgical cases of small bowel obstruction caused by the migration of fractured metal stent in patients with mGOO.

Cardiac 18F‑FDG uptake and new‑onset rectal cancer

The present study aimed to investigate the factors affecting the cardiac uptake of 18F-fluorodeoxyglucose (18F-FDG) during 18F-FDG positron emission tomography (PET) for new-onset rectal cancer and new-onset colon cancer (ascending, transverse, descending, sigmoid colon cancer) and to examine the association between the cardiac uptake of 18F-FDG and prognosis. The participants were diagnosed with new-onset rectal cancer and new-onset colon cancer (ascending, transverse, descending, sigmoid cancer) at the Iga City General Hospital (Iga, Japan) between January 1, 2013, and March 31, 2018, and underwent an 18F-FDG PET scan for pretreatment staging. The relationship between cardiac maximum standard uptake value (SUVmax), the presence/absence of distant metastasis and prognosis was examined. A total of 26 patients (14 men and 12 women) aged 72.0±10 years with new-onset rectal cancer were selected for the study. No patients had multiple simultaneous cancers. The median cardiac SUVmax was 3.8 and 2.5 in patients with no distant metastasis and distant metastasis, respectively, revealing a statistically significant difference (P<0.01). The median tumor volume on PET-computed tomography (CT) images was 7,815 cm² and was 66,248 cm² in patients with no distant metastasis and distant metastasis, respectively, revealing a statistically significant difference (P<0.01). Echocardiography findings revealed no significant difference between patients with and without distant metastasis. The correlation coefficient between cardiac SUVmax and total tumor volume on PET/CT images (primary + lymph + distant metastases) was statistically significant (r=-0.42, P=0.03). Analysis of the association between the occurrence of distance metastasis and cardiac SUVmax as a continuous variable gave a statistically significant result [hazard ratio (HR): 0.30, 95% confidence interval (CI): 0.09-0.98, P=0.045]. Receiver operating characteristic analysis showed a cardiac SUVmax of 2.6 with an area under the curve of 0.86 for determining the presence of distant metastasis (95% CI: 0.70-1.00). The median observation time was 56 months, and nine patients died during observation. Analysis of the association between the overall survival and cardiac SUVmax (cutoff: 2.6) showed 95% CI: 0.01-0.45 and HR: 0.06 (P<0.01); that between the overall survival and total tumor volume on PET images showed 95% CI: 1.00-1.00 and HR: 1.00 (P<0.01); and that between the overall survival and presence of distant metastasis showed 95% CI: 1.72-116.4 and HR: 14.1 (P<0.01). Furthermore, 25 patients (16 men and nine women) aged 71.4±14.2 years with new-onset colon cancer were selected for the study. Analysis of new-onset colon cancer revealed no statistically significance between the cardiac SUVmax and distant metastasis.

Lymphocyte-C-reactive Protein Ratio as Promising New Marker for Predicting Surgical and Oncological Outcomes in Colorectal Cancer

BACKGROUND

Systemic inflammation via host-tumor interactions is currently recognized as a hallmark of cancer. The aim of this study was to evaluate the prognostic value of various combinations of inflammatory factors using preoperative blood, and to assess the clinical significance of our newly developed inflammatory score in colorectal cancer (CRC) patients.

METHOD

In total 477 CRC patients from the discovery and validation cohorts were enrolled in this study. We assessed the predictive impact for recurrence using a combination of nine inflammatory markers in the discovery set, and focused on lymphocyte-C-reactive protein ratio (LCR) to elucidate its prognostic and predictive value for peri-operative risk in both cohorts.

RESULTS

A combination of lymphocytic count along with C-reactive protein levels demonstrated the highest correlation with recurrence compared with other parameters in CRC patients. Lower levels of preoperative LCR significantly correlated with undifferentiated histology, advanced T stage, presence of lymph node metastasis, distant metastasis, and advanced stage classification. Decreased preoperative LCR (using an optimal cut-off threshold of 6000) was an independent prognostic factor for both disease-free survival and overall survival, and emerged as an independent risk factor for postoperative complications and surgical-site infections in CRC patients. Finally, we assessed the clinical feasibility of LCR in an independent validation cohort, and confirmed that decreased preoperative LCR was an independent prognostic factor for both disease-free survival and overall survival, and was an independent predictor for postoperative complications and surgical-site infections in CRC patients.

CONCLUSION

Preoperative LCR is a useful marker for perioperative and postoperative management of CRC patients.

Identification of Predictors of Recurrence in Patients with Lower Rectal Cancer Undergoing Neoadjuvant Chemotherapy: A Direct Comparison of Short-Course and Long-Course Chemoradiotherapy

OBJECTIVE

This study aimed to investigate clinicopathological responses and oncological outcome in patients receiving short- or long-course chemoradiotherapy (CRT) and to assess the predictive factor for recurrence in each treatment.

METHODS

A total of 118 rectal cancer patients receiving preoperative CRT were enrolled. Clinicopathological responses and oncological outcome in patients receiving short- or long-course CRT were investigated.

RESULTS

Despite there being no significant differences in the prognosis of disease-free survival (DFS) based on TNM stage classification in patients receiving long-course CRT, patients with advanced stage demonstrated poor DFS after short-course CRT. The presence of lymph node metastasis was a predictor of poor DFS in short-course CRT, whereas poor pathological response was a predictor of recurrence in long-course CRT.

CONCLUSIONS

Distinct predictors of recurrence depending on the CRT course might be needed to discriminate candidates from rectal cancer patients receiving preoperative CRT who might benefit from more intensive adjuvant therapy after surgery.

Downregulation of trefoil factor-3 expression in the rectum is associated with the development of ulcerative colitis-associated cancer

Diagnostic markers facilitate more selective screening and treatment strategies for ulcerative colitis (UC)-associated cancer (UCAC). The expression of trefoil factor-3 (TFF3), which is involved in mucosal protection and repair in the gastrointestinal tract, was analyzed and its significance for UCAC was evaluated. A total of 145 patients with UC who underwent proctocolectomies were enrolled, including 15 patients (10.8%) with UCAC. TFF3 expression in the rectal mucosa and in cancer cells was assessed using immunohistochemistry, and the expression in UCAC and sporadic colorectal cancer was compared. Analyzing the mucinous granules of goblet cells located in crypts revealed that the non-cancerous rectal mucosa of patients with UCAC had significantly lower mean TFF3 staining scores compared with patients with UC without UCAC or patients with sporadic cancer. TFF3 staining score was revealed to be an independent predictor of UCAC development. These results indicated that low TFF3 expression in the rectal mucosa was associated with the development of UCAC. Thus, TFF3 expression in the rectal mucosa may be a useful biomarker for monitoring patients with UC.

Colony-stimulating factor-1 and colony-stimulating factor-1 receptor co-expression is associated with disease progression in gastric cancer

Colony‑stimulating‑factor‑1 (CSF‑1) is a hematopoietic growth factor that exerts its effects through the c‑fms/CSF‑1 receptor (CSF‑1R). The CSF‑1/CSF‑1R axis is thought to be involved in the development of several types of cancer. This study aimed to clarify the clinical and biological significance of the CSF‑1/CSF‑1R axis in gastric cancer (GC). For this purpose, we evaluated CSF‑1 and CSF‑1R expression in GC tissues from 148 patients by RT‑qPCR and immunohistochemistry. The biological roles of the CSF‑1/CSF‑1R axis were investigated by measuring the cell proliferation and migration, and anoikis resistance in a human GC cell line following treatment with recombinant human CSF‑1 and/or CSF‑1R inhibitor. The results revealed that an elevated expression of CSF‑1 or CSF‑1R significantly correlated with disease progression and with a poor overall survival (OS, P=0.037 and 0.016, respectively) and disease‑free survival (DFS, P<0.001 and <0.001, respectively) of patients with GC. Furthermore, a high co‑expression of CSF‑1 and CSF‑1R was an independent prognostic factor for OS (HR, 1.38; 95% CI, 1.02‑1.88; P=0.038) and DFS (HR, 1.79; 95% CI, 1.21‑2.67; P=0.004), and an independent risk factor for lymph node and peritoneal metastasis. Immunohistochemical analysis revealed an intense CSF‑1/CSF‑1R expression in the cytoplasm of cancer cells in primary GC tissues. CSF‑1 or CSF‑1R expression positively correlated with vascular endothelial growth factor A (VEGFA) or Fms related tyrosine kinase 1 (FLT1) expression in GC tissues. Treatment with recombinant human CSF‑1 promoted proliferation, migration and anoikis resistance in a GC cell line. These effects were generally blocked by CSF‑1R inhibition. On the whole, the findings of this study indicate that the CSF‑1/CSF‑1R axis may be a clinically useful prognostic and predictive biomarker for lymph node and peritoneal metastasis and a potential therapeutic target in GC.

Clinical Burden of Modified Glasgow Prognostic Scale in Colorectal Cancer

BACKGROUND/AIM

This study aimed to clarify the potential of modified Glasgow Prognostic Score (mGPS) as a prognostic biomarker and reveal the significance of fish oil (FO)-enriched nutrition in colorectal cancer (CRC).

PATIENTS AND METHODS

A total of 738 CRC patients from three different patient cohorts, including 670 patients in the biomarker study and 68 patients in the nutrition-intervention study, were analyzed.

RESULTS

High preoperative mGPS was significantly correlated with well-recognized disease progression factors and advanced UICC stage classification. In addition, high mGPS was an independent prognostic factor in both cohorts, especially in stage III and IV patients. These statuses were maintained in postoperative course and correlated with sarcopenia. Furthermore, FO-enriched nutrition suppressed systemic inflammatory reaction and improved skeletal muscle mass and prognosis, especially in CRC patients with mGPS 1 or 2.

CONCLUSION

Assessment of mGPS could identify patients with high-risk CRC, who might be candidates for FO-enriched nutrition.

Feasibility of Assessing Prognostic Nutrition Index in Patients With Rectal Cancer Who Receive Preoperative Chemoradiotherapy

BACKGROUND

Malnutrition can adversely affect treatment responses and oncological outcomes in cancer patients. However, among patients with rectal cancer who undergo chemoradiotherapy (CRT), the significance of peri-treatment nutrition assessment as a predictor of treatment response and outcome remains unclear.

OBJECTIVE

The aim of this study was to determine whether the Prognostic Nutrition Index (PNI) based on peri-treatment serum can be used as a predictor of treatment response and outcome in patients with rectal cancer who undergo CRT.

DESIGN, SETTING, AND PATIENTS

We analyzed 114 patients with rectal cancer who received preoperative CRT followed by total mesorectal excision at our institution.

RESULTS

Post-CRT PNI was significantly lower than pre-CRT PNI in rectal cancer patients. Although post-CRT PNI did not significantly correlate with either overall survival or disease-free survival, low pre-CRT PNI was significantly associated with shorter overall survival and disease-free survival in this population and was also an independent risk factor for ineffectiveness of long-course preoperative CRT. Finally, low pre-CRT PNIs were a stronger indicator of poor prognosis and early recurrence in patients with pathological lymph node metastasis (who generally need to receive postoperative chemotherapy), than in those with no pathological lymph node metastasis.

CONCLUSION

Pretreatment PNI could be useful in evaluating and managing patients with rectal cancer who undergo CRT followed by curative resection.

Successful identification of a predictive biomarker for lymph node metastasis in colorectal cancer using a proteomic approach

Colorectal cancer (CRC)-associated mortality is primarily caused by lymph node (LN) and distant metastasis, highlighting the need for biomarkers that predict LN metastasis and facilitate better therapeutic strategies. We used an Isobaric Tags for Relative and Absolute Quantification (iTRAQ)-based comparative proteomics approach to identify novel biomarkers for predicting LN metastasis in CRC patients. We analyzed five paired samples of CRC with or without LN metastasis, adjacent normal mucosa, and normal colon mucosa, and differentially expressed proteins were identified and subsequently validated at the protein and/or mRNA levels by immunohistochemistry and qRT-PCR, respectively. We identified 55 proteins specifically associated with LN metastasis, from which we selected ezrin for further analysis and functional assessment. Expression of ezrin at both the protein and mRNA levels was significantly higher in CRC tissues than in adjacent normal colonic mucosa. In univariate analysis, high ezrin expression was significantly associated with tumor progression and poor prognosis, which was consistent with our in vitro findings that ezrin promotes the metastatic capacity of CRC cells by enabling cell invasion and migration. In multivariate analysis, high levels of ezrin protein and mRNA in CRC samples were independent predictors of LN metastasis. Our data thus identify ezrin as a novel protein and mRNA biomarker for predicting LN metastasis in CRC patients.

Prevalence of anastomotic leak and the impact of indocyanine green fluorescein imaging for evaluating blood flow in the gastric conduit following esophageal cancer surgery

BACKGROUNDS AND AIM

Anastomotic leak (AL) following esophagectomy for esophageal cancer (EC) remains an important cause of prolonged hospitalization and impaired quality of life. Recently, indocyanine green (ICG) fluorescein imaging has been used to evaluate the gastric conduit blood supply during EC surgery. Although several factors have been reported to be associated with AL, no studies have evaluated the relationships between risk factors for AL, including ICG fluorescein imaging. The purpose of this study was to investigate the risk factors associated with AL following esophagectomy and to evaluate the impact of ICG fluorescein imaging of the gastric conduit during EC surgery.

METHODS

One hundred and twenty patients undergoing esophagectomy with esophagogastric anastomosis for EC were enrolled in this retrospective study. Clinicopathological factors, preoperative laboratory variables, and surgical factors, including ICG fluorescence imaging, were analyzed to determine their association with AL. Univariate and multivariate logistic regression analysis was used to evaluate the impact of each of these factors on the incidence of AL.

RESULTS

Among the 120 patients enrolled in the study, 10 (8.3%) developed AL. Univariate analysis demonstrated an increased risk of AL in patients with a high-neutrophil-to-lymphocyte ratio (p = 0.0500) and in patients who did not undergo ICG fluorescein imaging (p = 0.0057). Multivariate analysis revealed that the absence of ICG imaging was an independent risk factor for AL (p = 0.0098).

CONCLUSIONS

Using ICG fluorescein imaging to evaluate blood flow in the gastric conduit might decrease the incidence of AL following EC surgery.

Proteomics analysis of differential protein expression identifies heat shock protein 47 as a predictive marker for lymph node metastasis in patients with colorectal cancer

The discovery of biomarkers to predict the potential for lymph node (LN) metastasis in patients with colorectal cancer (CRC) is essential for developing improved strategies for treating CRC. In the present study, they used isobaric tags for relative and absolute quantitation to conduct a proteomic analysis designed to identify novel biomarkers for predicting LN metastasis in patients with CRC. They identified 60 differentially expressed proteins specifically associated with LN metastasis in CRC patients and classified the molecular and functional characteristics of these proteins by bioinformatic approaches. A literature search led them to select heat shock protein 47 (HSP47) as the most suitable candidate biomarker for predicting LN metastasis. Validation analysis by immunohistochemistry showed that HSP47 expression in patients with CRC and the number of HSP47-positive spindle cells in the tumor stroma were significantly higher compared with those in adjacent normal colonic mucosa, and the number of the latter cells increased with tumor progression. Further, the number of HSP47-positive spindle cells in stroma was a more informative marker for identifying LN metastasis than HSP47expression. Multivariate analysis identified spindle cells that expressed elevated levels of HSP47 as an independent predictive biomarker for CRC with LN metastasis. Moreover, these cells served as an independent marker of disease-free and overall survival of patients with CRC. Their data indicate that the number of HSP47-positive spindle cells in the stroma of CRC may serve as a novel predictive biomarker of LN metastasis, early recurrence and poor prognosis.

Prognostic impact of preoperative albumin to globulin ratio in curative colon cancer patients

647

Background: Albumin to globulin ratio (AGR) has been reported to predict long term mortality in patients with several cancers. However, prognostic impact of preoperative AGR in colon cancer patients with curative intent has not yet been fully addressed. Therefore, we, for the first time, investigated the association between AGR and clinico-pathological findings including overall survival (OS) and disease free survival (DFS) in stage I-III colon cancer patients. Methods: Clinicopathological findings including preoperative laboratory data (carcinoembryonic antigen [CEA] and AGR) from 251 curative colon cancer patients were assessed as indicators of early recurrence and poor prognosis in this retrospective study. AGR was calculated as [AGR = albumin/ (total protein - albumin)]. The cut-off value of AGR was 1.32 in current study. Results: Several clinicopathological categories related with tumor progression such as lymph node metastasis, T4 tumor, large tumor size, undifferentiated tumor, venous and lymphatic invasion, and high CEA were significantly associated with low AGR level. The patients with low AGR were significantly poorer OS (P = 0.001) and DFS (P = 0.003) than those with high AGR, respectively. In addition, multivariate analyses demonstrated that low AGR was independently associated with early recurrence (HR = 2.87, P = 0.007) and poor prognosis (HR = 2.56, P = 0.008), respectively. On the other hand, sub analysis of survival curves revealed that stage III colon cancer patients with low AGR were significantly poorer OS (P = 0.007) and DFS (P = 0.02) than those with high AGR, respectively. Furthermore, significantly poorer OS and DFS were also shown in stage I-II colon cancer patients with low AGR, respectively (OS: P = 0.02, DFS: P = 0.01). Conclusions: Preoperative AGR was an independent predictor of early recurrence and poor prognosis in curative colon cancer patients. AGR may represent a simple, potentially useful predictive biomarker for selecting stage I-II colon cancer patients who might need adjuvant chemotherapy. Furthermore, AGR may select candidates who are better to introduce more intensive adjuvant chemotherapy after curative operation in stage III colon cancer patients.

Modified Glasgow prognostic score as a selection marker for colorectal cancer patients with multiple metastases who can underwent primary site resection followed by multidisciplinary therapy

655

Background: We often encounter the colorectal cancer (CRC) patients with multiple distant metastases who rapidly progress after resection of primary tumor site due to preventing bowel obstruction, tumor bleeding and perforation. However, there has been few knowledge for identification of these patients at the present time. In this study, we evaluated the association between clinicopathological findings, including with preoperative laboratory data and survival outcome, and possibility of multimodality therapy in CRC patients with multiple metastases after resection of primary tumor lesion. Methods: Clinicopathological findings and preoperative laboratory data, including carcinoembryonic antigen (CEA) and systemic inflammatory response markers, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and modified Glasgow Prognosis Score (mGPS) for 92 CRC patients with multiple metastases from 2005 to 2014 were collected. We performed multivariate analysis for overall survival (OS) in cox proportional hazard model. In addition, we performed multivariate logistic regression analysis to evaluate the factors influencing possibility of postoperative multimodality therapy. Results: Postoperative multimodality therapy improved overall survival significantly. Among serum markers, elevated CEA, NLR, and mGPS were significant indicators of poorer OS. Multivariate analysis for OS revealed that elevated CEA (P = 0.026), mGPS (P = 0.038), and undifferentiated histology type (P = 0.02) were independent poorer prognostic factors. In addition, multivariate logistic regression analysis showed that elevated mGPS (P = 0.029) and higher age (P = 0.013) were independent risk factors for difficulty of introducing postoperative multidisciplinary therapy. Conclusions: Preoperative mGPS is useful objective marker for selection of colorectal cancer patients with multiple metastases who can undergo primary resection followed by multidisciplinary therapy.

Preoperative evaluation of heat shock protein 47 expression to identify patients with colorectal cancer with lymph node metastasis and poor prognosis

546

Background: Accumulating evidences reveal that overexpression of Heat shock protein 47 (HSP47) increase cancer progression, and that HSP47 expression in the tumor-associated stroma serve as diagnostic marker in various cancers. In addition, we recently performed immunohistochemistry to evaluate HSP47 expression in surgical colorectal cancer (CRC) specimens, and showed that the count of HSP47 positive spindle cell in cancer stroma was significantly associated with lymph node (LN) metastasis, early recurrence and poor prognosis in CRC patients. Thus, evaluating HSP47 expression in CRCs preoperatively may be valuable for planning the treatment of patients with CRC. In this study, we quantified the messenger RNA(mRNA) expression of HSP47 in CRCs by using preoperative biopsy samples, and analyzed the association between HSP47 mRNA expression and clinico-pathological factors including prognosis in patients with CRC. Methods: A total of 139 CRC samples, which were taken by biopsy before surgery at Mie University Hospital from 2000 to 2005, were enrolled. HSP47 gene expression was determined by quantitative real-time reverse transcription–PCR using Power SYBR Green PCR methods. Results: All CRC patients were classified according to the tumor-node-metastasis (TNM) classification system as follows: stage I (n = 33); stage II (n = 44); stage III (n = 33), and stage IV (n = 29). High HSP47 expression in CRC was significantly associated with higher T stage (p = 0.0163), LN metastasis (p = 0.0186), vessel invasion (p = 0.0328) and higher TNM staging (p = 0.0115). Kaplan-Meier analysis showed that patients with high HSP47 expression had significantly poorer overall survival (OS) than those with low (p = 0.0003). Furthermore, multivariate analyses revealed that HSP47 expression was an independent predictive marker for LN metastasis and poor OS in CRC patients, respectively (LN metastasis; OR; 2.3946, p = 0.0249, OS; HR; 2.7407, p = 0.00224). Conclusions: In conclusion, quantification of HSP47 expression using biopsy samples can identify the CRC patients who may suffer from LN metastasis and poor prognosis, preoperatively.

Metastasis-associated protein is a predictive biomarker for metastasis and recurrence in gastric cancer

The metastasis-associated (MTA) gene family is a critical component of the nucleosome remodeling and histone deacetylase complex, and plays an important role in metastatic processes. We systematically evaluated dysregulation of the MTA family to clarify their clinical significance in gastric cancer (GC). One hundred and forty-five patients who underwent surgery for GC were evaluated. We analyzed the expression levels of the MTA family (MTA1, 2 and 3) by qPCR in GC tissue, and the MTA1 protein expression in primary cancer and matched normal mucosa (NM) was measured using immunohistochemical analysis. The expression of all the MTA family members was significantly increased in a stage-dependent manner, and elevated expression of all of the MTA family members was correlated with metastatic factors and prognosis in GC patients. Multivariate analysis revealed that MTA1 overexpression was an independent risk factor for survival. Especially, elevated expression of MTA1 was significantly correlated with recurrence, and was an independent risk factor for lymph node metastasis. Immunohistochemical analysis demonstrated that MTA1 was predominantly expressed in the nuclei of primary GC cells but was not expressed in NM and in the cancer stroma. In conclusion, quantification of MTA expression may support the accurate diagnosis of disease staging and may help predict clinical outcomes.

Circulating microRNA-1290 as a novel diagnostic and prognostic biomarker in human colorectal cancer

BACKGROUND

Circulating microRNAs (miRNAs) are attracting major interest as potential non-invasive biomarkers for colorectal cancer (CRC). This study aimed to identify a novel serum miRNA biomarker for the early detection and/or evaluating prognosis of CRC patients.

PATIENTS AND METHODS

Comprehensive miRNA array analysis was carried out using serum samples from patients with colorectal neoplasia and healthy controls. Next, to verify whether the candidate miRNA possessed a secretory potential, we screened miRNA expression levels in culture medium from 2 CRC cell lines, followed by serum analysis from 12 stage IV CRC, 12 adenoma, and 12 control subjects. Thereafter, we validated expression of candidate miRNAs in 179 primary CRC tissues, as well as serum samples from an independent cohort of 211 CRCs, 56 adenomas, and 57 control subjects.

RESULTS

Through microarray analysis, we identified significantly higher levels of miRNA-1290 (miR-1290) in serum from patients with colorectal adenomas and cancers. We verified miR-1290 overexpression in serum of CRC patients in a training cohort. In the validation cohort, serum miR-1290 levels were significantly up-regulated in patients with colorectal adenomas (P < 0.0001) and cancers (P < 0.0001). Serum miR-1290 levels could robustly distinguish adenoma [area under the curve (AUC) = 0.718] and CRC patients (AUC = 0.830) from normal subjects. High miR-1290 expression in serum and tissue was significantly associated with tumor aggressiveness and poor prognosis. Moreover, serum miR-1290 levels were an independent prognostic factor [hazard ratio (HR) = 4.51; 95% confidence interval (CI) = 1.23-23.69; P = 0.0096] and an independent predictor for tumor recurrence (hazard ratio = 3.92; 95% confidence interval = 1.11-25.14; P = 0.032) in CRC.

CONCLUSIONS

Serum miR-1290 is a novel biomarker for early detection, recurrence, and prognosis in CRC.

Abstract 5016: Elevated serum monocyte chemotactic protein 4 (MCP4) as a novel noninvasive prognostic and predictive biomarker for detection of metastasis in colorectal cancer

Purpose. Despite the recent progress in diagnosis and treatment for colorectal cancer (CRC), prognosis of CRC patients still remains poor. Metastatic recurrence is the major causes of cancer-related death in CRC patients, and recent progress in treatment options, especially technical advances in invasive treatment for metastatic lesion, have improved the prognosis of CRC patients with metastasis. Furthermore, almost half of patients that receive chemotherapy derive no clinical benefit, though all are exposed to these severe toxic and expensive therapeutic regimens in patients with metastatic CRC patients. In view of these underlying issues, for improvement of patient's prognosis, there is a keen interest in developing robust biomarkers that can identify the subset of patients who can benefit from intensive post-treatment surveillance protocols for early detection of recurrence, and prompt decision of appropriate treatment protocol. Herein, we systemically and comprehensively evaluated differentially levels of serum cytokines using array-based techniques to identify novel and reliable serum biomarker to predict metastasis and poor outcome in CRC.

Methods. The study design included an initial dual screening phases, and followed by a subsequent clinical validation phase in this study.In discovery phase, we examined cytokine profiling using preoperative serum from two different CRC cohorts (n = 30) to identify differentially expressed serum cytokines in CRC patients with metastasis. In validation phase, serum levels of MCP-4 were assessed in 194 CRC patients by enzyme-linked immunosorbent assay, and their relationships with clinicopathological findings, including recurrence and survival, were investigated.

Results. In discovery phase, three cytokines (elevated: MCP-4, ENA-78; decreased:Ckb8-1) were overlapped as a differentially expressed cytokines in serum from CRC patients with metastasis compared those without metastasis. High serum MCP-4 was significantly associated with older age (p = 0.033), advanced T stage (p = 0.029), distant metastasis (p = 0.011) and UICC stage classification (p = 0.006). Cox regression analysis showed that elevated MCP-4 was a significant and independent prognostic factor of disease free survival (HR:2.6, 95%CI:1.0-6.7) and overall survival (HR:2.7, 95%CI:1.3-5.9) in all CRC patients. Furthermore, logistic regression analysis revealed that high serum MCP-4 level was an independent marker in predicting distant metastasis in CRC (OR:3.8, 95%CI:1.3-10.9).

Conclusion. Our comprehensive study highlights the clinical feasibility of serum MCP-4 as a prognostic and predictive biomarker for distant metastasis and recurrence in CRC patients. Quantification of serum MCP-4 concentration might support the early detection/prediction of recurrence and may contribute to the prediction of clinical outcomes in CRC.

Citation Format: Yoshinaga Okugawa, Yuji Toiyama, Koji Tanaka, Mikio Kawamura, Takahito Kitajima, Tadanobu Shimura, Hiroki Imaoka, Hiroyuki Fujikawa, Susumu Saigusa, Yasuhiro Inoue, Motoyoshi Tanaka, Yasuhiko Mohri, Chikao Miki, Ajay Goel, Masato Kusunoki. Elevated serum monocyte chemotactic protein 4 (MCP4) as a novel noninvasive prognostic and predictive biomarker for detection of metastasis in colorectal cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 5016.

Abstract 1967: MicroRNA-1290 promotes tumor progression and acts as a novel biomarker for poor prognosis in human colorectal cancer

Background:

MicroRNA (miRNA)-1290 is known to activate Wnt signaling pathway and increase the reprogramming-related transcript factors c-Myc and Nanog. Additionally, miR-1290 promotes the epithelial-mesenchymal transition and interferes with cellular differentiation. Previous report demonstrated that overexpressing miR-1290 shows extensive atrophy and intestinal metaplasia of the gastric mucosa, indicating that miR-1290 is involved in the precancerous lesions of the gastric epithelial cells. However, to the best of our knowledge, miR-1290 expression pattern, its clinical significance and molecular mechanism in colorectal cancer (CRC) have not been investigated.

Materials and Methods:

We screened miR-1290 expression in a subset of 36 tissue samples from normal colonic mucosa (n = 12), adenoma (n = 12) and CRC (n = 12). Next, we further validated miR-1290 expression in a larger, independent cohort, which included normal colonic mucosa (n = 21), adenoma (n = 26) and CRC (n = 179), and investigated the clinical significance of miR-1290 in CRC. In addition, CRC cell lines were transfected with anti-miR against miR-1290 for the assessment of its function.

Results:

In screening step, miR-1290 expression stepwise increased according to adenoma-carcinoma sequence, and its expression in adenoma and CRC was significantly higher than that in normal colonic mucosa, respectively (adenoma: p&lt;0.0001, CRC: p&lt;0.0001). In validation step, we confirmed miR-1290 expression in both adenoma and CRC was significantly higher than that in normal colonic mucosa (adenoma: p&lt;0.0001, CRC: p&lt;0.0001). In addition, miR-1290 expression in CRC gradually increased according to TNM stage and significantly higher in stage IV. High expression in CRC were significantly associated with large tumor size (&gt;40mm), high grade of T stage (T3/4), lymphatic and venous invasion positive, lymph node metastasis and liver metastasis. In addition, Kaplan-Meier survival curves revealed that the CRC patients with high miR-1290 expression were significantly poorer overall survival than that with low expression, respectively (p = 0.0082). Our in vitro study demonstrated that attenuated miR-1290 expression resulted in inhibition of proliferation, invasion and migration capacity of CRC cell lines.

Conclusions:

We, for the first time, demonstrated that miR-1290 in CRC acts as onco-miRNAs that is supported by several evidences from our in vitro analysis and clinical data. MiR-1290 is significantly associated with malignant potential of CRC and can be the biomarker for predicting poor prognosis in patients with CRC.

Citation Format: Yuka Nagano, Yuji Toiyama, Hiroki Imaoka, Hiroyuki Fujikawa, Junichiro Hiro, Susumu Saigusa, Minako Kobayashi, Toshimitsu Araki, Masaki Ohi, Koji Tanaka, Yasuhiro Inoue, Yasuhiko Mohri, Kenichiro Ishii, Masato Kusunoki. MicroRNA-1290 promotes tumor progression and acts as a novel biomarker for poor prognosis in human colorectal cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1967.

Circulating microRNA-203 predicts metastases, early recurrence, and poor prognosis in human gastric cancer

BACKGROUND

Metastasis is a major cause of death in patients with gastric cancer (GC). MicroRNAs (miRNAs) relating to the epithelial-mesenchymal transition (EMT) control GC progression and metastasis. The aim of this study was to evaluate serum EMT-associated miRNAs for metastatic and prognostic noninvasive biomarkers in GC.

METHODS

In the first step of this study (preliminary experiments), we selected candidate miRNAs associated with metastasis by analyzing the expression of the miR-200 family (miR-200a, miR-200b, miR-200c, miR-141, and miR-429) and miR-203 in serum samples from stage I (n = 12) and stage IV (n = 12) GC patients. The second phase involved the independent validation of candidate miRNAs in serum specimens from 130 patients with GC and 22 controls.

RESULTS

Based on the preliminary experiments, miR-203 was selected as the candidate serum miRNA that was most closely associated with metastasis. Validation analysis revealed that serum miR-203 levels were significantly lower in stage IV than stage I-III GC patients. Serum miR-203 expression was significantly lower in GC patients with a higher T stage, vessel invasion, and lymph node, peritoneal, and distant metastases. Low expression of serum miR-203 was significantly associated with poor disease-free and overall survival. Multivariate analysis revealed that low serum miR-203 expression was an independent predictive marker for lymph node, peritoneal, and distant metastases and a poor prognosis in patients with GC.

CONCLUSIONS

Serum miR-203 has the potential to serve as a noninvasive biomarker for prognosis and to predict metastasis in patients with GC.

Intravital imaging of the effects of 5-fluorouracil on the murine liver microenvironment using 2-photon laser scanning microscopy

5-fluorouracil (5FU) is often used in the treatment of colorectal cancer. 5FU improves the median overall and disease-free survival rates and reduces recurrence rates in patients who have undergone curative surgical resection. However, in the adjuvant setting, whether 5FU eradicates clinically undetectable micrometastases in target organs such as the liver, or whether 5-FU inhibits the adhesion of circulating tumor cells has not yet been established. In the present study, 5FU was administered following the inoculation of red fluorescent protein-expressing HT29 cells into green fluorescent protein (GFP)-transgenic nude mice to examine its inhibitory effect. 2-photon laser scanning microscopy was performed at selected time points for time-series imaging of liver metastasis of GFP-transgenic mice. The cell number in vessels was quantified to evaluate the response of the tumor microenvironment to chemotherapy. HT29 cells were visualized in hepatic sinusoids at the single-cell level. A total of 2 hours after the injection (early stage), time-series imaging revealed that the number of caught tumor cells gradually reduced over time. In the 5FU treatment group, no significant difference was observed in the cell number in the early stage. One week after the injection (late stage), a difference in morphology was observed. The results of the present study indicated that 5FU eradicated clinically undetectable micrometastases in liver tissues by acting as a cytotoxic agent opposed to preventing adhesion. The present study indicated that time-series intravital 2-photon laser scanning microscopic imaging of metastatic tumor xenografts may facilitate the screening and evaluation of novel chemotherapeutic agents with less interindividual variability.

Clinical significance of enlarged lateral pelvic lymph nodes before and after preoperative chemoradiotherapy for rectal cancer

Preoperative chemoradiotherapy (CRT) with total mesorectal excision (TME) is the widely accepted treatment for rectal cancer (RC) in Western countries. However, there remains controversy as to whether preoperative CRT is useful in tumors that extend beyond the mesorectum, including metastasis to the lateral pelvic lymph nodes (LPLN). The aim of this study was to assess the prognostic significance of LPLN enlargement in patients with RC who receive preoperative CRT followed by TME without LPLN dissection. We evaluated the prognostic effect of radiographic LPLN enlargement before and after CRT, as well as the patients' clinicopathological and genetic profiles. Of the 104 patients investigated, pretreatment imaging identified 19 (18%) as LPLN-positive (>7 mm in diameter). Of these 19 patients, 7 (37%) exhibited LPLN downsizing to <7 mm following CRT. The median follow-up period was 52 months. The 5-year cancer-specific survival (CSS) or relapse-free survival (RFS) did not differ significantly between patients who did and those who did not have positive LPLN on pretreatment imaging. However, LPLN that remained positive after CRT were significantly associated with poorer 5-year CSS (73 vs. 84%, respectively; P=0.0052) and RFS (32 vs. 78%, respectively; P=0.0264). None of the patients whose LPLN were downsized to <7 mm following CRT developed recurrence; however, those with positive LPLN after CRT had a 55% higher recurrence rate, characterized by delayed local recurrence, a pattern that may be affected by certain chemokines. In conclusion, changes in initially positive LPLN (>7 mm) may predict the prognosis of patients with RC who receive preoperative CRT-TME. LPLN positivity after CRT was associated with shorter CSS and RFS. Strategies to improve patient survival may include selective LPLN dissection or more aggressive multimodality therapy.

miRNA-503 Promotes Tumor Progression and Is Associated with Early Recurrence and Poor Prognosis in Human Colorectal Cancer

OBJECTIVES

MicroRNA (miR)-503 is downregulated in several cancers and plays a tumor-suppressive role in carcinogenesis. However, the miR-503 expression pattern, its clinical significance and its molecular mechanism in colorectal cancer (CRC) have not been investigated.

METHODS

We analyzed miR-503 expression in normal mucosa (n = 20), adenoma (n = 27) and CRC (n = 20). We quantified miR-503 expression in an independent cohort (n = 191) and investigated the clinical significance of miR-503 in CRC. CRC cell lines were transfected with anti-miR-503 to assess its function and target gene.

RESULTS

miR-503 expression increased according to the adenoma-carcinoma sequence. High miR-503 expression was significantly associated with large tumor size, serosal invasion, lymphatic and venous invasion as well as lymph node metastasis. CRC patients with high miR-503 expression had significantly earlier relapse and poorer prognosis than those with low expression. miR-503 was an independent recurrence marker in stage I/II CRC. In vitro, attenuated miR-503 expression resulted in inhibition of proliferation, invasion and migration and acquisition of anoikis of CRC cells. The putative target gene (calcium-sensing receptor) was significantly upregulated after miR-503 attenuation.

CONCLUSIONS

miR-503 acts as an 'onco-miR' in CRC. High miR-503 expression is associated with early recurrence and poor prognosis in CRC.

Distinguishing between limited systemic scleroderma-associated pseudo-obstruction and peritoneal dissemination

A 78-year-old woman receiving treatment for limited systemic scleroderma (SSc) underwent high anterior resection and partial liver resections for rectosigmoid colon cancer with multiple liver metastases. A year after surgery, an abdominal computed tomography (CT) demonstrated suspicion for peritoneal dissemination with an increase in ascites, and (18)F-fluorodeoxy glucose-positron emission tomography-CT was suggestive of carcinomatosis. We began to decompress the small intestine and administer octreotide. However, the intestinal obstruction did not improve. Although intestinal pseudo-obstruction caused by limited SSc was considered as a differential diagnosis, we performed an exploratory laparotomy because the possibility of peritoneal dissemination-associated obstruction could not be excluded. We observed a moderate amount of serous ascites and dilatation of the small intestine that was white in color, hard, and with limited contractility. There was no evidence of peritoneal dissemination nor of mechanical obstruction. Our experience thus shows the difficulty of distinguishing SSc-associated intestinal pseudo-obstruction from peritoneal dissemination.

Implication of programmed cell death ligand 1 expression in tumor recurrence and prognosis in rectal cancer with neoadjuvant chemoradiotherapy

BACKGROUND

Programmed cell death ligand 1 (PD-L1) regulates immune responses through interaction with its receptor. PD-L1 is not only a predictor of poor prognosis but also a new therapeutic target in several malignancies. Neoadjuvant chemoradiotherapy (CRT) is an effective tool for local control of rectal cancer, but the disease recurrence rate remains high. The aim of this study was to retrospectively evaluate the correlation between PD-L1 expression and clinicopathological variables in rectal cancer after neoadjuvant CRT.

MATERIALS AND METHODS

A total of 90 rectal cancer patients who underwent neoadjuvant CRT were enrolled in this study. We evaluated PD-L1 expression using immunohistochemistry. Moreover, we investigated the correlation between PD-L1 expression and tumor-infiltrating T cells, and between CD8- and Foxp3-positive cells.

RESULTS

Patients with high PD-L1 expression more frequently had vascular invasion and tumor recurrence compared to patients with low PD-L1 expression (P = 0.0225 and P = 0.0051). High PD-L1 expression was significantly associated with poor recurrence-free and overall survival (P = 0.0027 and P = 0.0357). Multivariate analysis revealed lymph node metastasis and high PD-L1 expression as independent risk factors for tumor recurrence (P = 0.0102 and P = 0.0374). Numbers of infiltrating CD8-positive cells in patients with high PD-L1 expression were significantly lower than in patients with low PD-L1 expression (P = 0.0322).

CONCLUSION

Our data suggest that inhibition of PD-L1 may be a new immunotherapeutic strategy to reduce tumor recurrence and improve prognosis in patients with rectal cancer after neoadjuvant CRT.

Preoperative prediction of peritoneal metastasis in gastric cancer as an indicator for neoadjuvant treatment

14

Background: Although Gastric cancer (GC) mortality has been reduced by advances in new treatments and in chemotherapy, it still has a poor prognosis and high mortality. One of the reasons for poor prognosis is that at the time of diagnosis advanced GC with metastatic disease is often detected and it is frequently accompanied by peritoneal metastasis. Imaging studies are frequently used to predict peritoneal metastasis, however, these modalities did not obtain consistently high sensitivity and specificity in assessing peritoneal metastasis. Therefore, we investigated whether the combination of several serum markers and clinical factors could be used for preoperative prediction of peritoneal metastasis in GC as an indicator for neoadjuvant treatment. Methods: A total of 493 patients with GC were enrolled in our Hospital. Preoperative serum tumor markers [carcinoembryonic antigen (CEA) and carbohydrate antigen (CA)19-9], systemic inflammatory marker C-reactive protein (CRP), host immune markers [neutrophil and lymphocyte counts and their ratio (NLR)], albumin as a nutritional marker, and objective preoperative clinical factors were available as indicators of postoperative peritoneal metastasis. Results: This study included a total of 344 men and 149 women who were classified according to UICC TNM Classification: 264 patients had stage I disease, 79 stage II, 78 stage III and 72 stage IV. Specific clinical factors, including tumor size, histopathology of biopsy sample, and tumor morphology, were significantly correlated with peritoneal metastasis. CA19-9, lymphocyte count and NLR were also predictive factors for peritoneal metastasis. Multivariate analysis identified the clinical factors tumor morphology and histopathology, and laboratory markers CA19-9 and lymphocyte count as independent factors predictive for peritoneal metastasis. Next, a combination of independent predictive factors achieved high predictive accuracy (0.882) for peritoneal metastasis preoperatively. Conclusions: A combination of preoperative tumor features and serum parameters is an alternative method to preoperatively discriminate patients with GC with peritoneal metastasis from those without.

Serum angiopoietin-like protein 2 as a potential biomarker for diagnosis, early recurrence and prognosis in gastric cancer patients

Chronic inflammation of gastric mucosa by Helicobacter pylori infection can initiate gastric carcinogenesis. As angiopoietin-like protein 2 (ANGPTL2) mediates inflammation and inflammation-associated carcinogenesis, we investigated the functional and clinical significance of ANGPTL2 in human gastric cancer (GC). SiRNA knockdown studies were performed for the functional assessment of ANGPTL2 in GC cell lines. ANGPTL2 expression was evaluated immunohistochemically in 192 tissue specimens from GC patients. In addition, we screened serum ANGPTL2 levels from 32 GC patients and 23 healthy controls; and validated these results in 194 serum samples from GC patients and 45 healthy controls by ELISA. ANGPTL2 knockdown caused anoikis and inhibited proliferation, invasion and migration in GC cells. ANGPTL2 expression was upregulated in GC tissues compared to normal gastric mucosa; and high ANGPTL2 expression was significantly associated with tumor progression, early recurrence (P = 0.003) and poor prognosis (P = 0.007). Serum ANGPTL2 in GC patients was significantly higher than for healthy controls (P < 0.05), and accurately distinguished GC patients from healthy control (AUC = 0.865). The validation step confirmed significantly higher serum ANGPTL2 levels in GC patients than healthy controls (P < 0.0001). Receiver operating characteristic curves yielded robust AUC value (0.831) accompanied by high sensitivity (73.0%) and specificity (82.2%) in distinguishing GC patients from healthy controls. High serum ANGPTL2, rather than its expression in matched tissues, was significantly associated with tumor progression, and emerged as an independent marker for recurrence (HR: 5.05, P = 0.0004) and prognosis (HR: 3.6, P = 0.01). Serum ANGPTL2 expression is a potential noninvasive biomarker for diagnosis, early recurrence and prognosis of GC patients.

Angiopoietin-like Protein 2 as a Predictor of Early Recurrence in Patients After Curative Surgery for Gastric Cancer

BACKGROUND

Angiopoietin-like protein-2 (ANGPTL2) mediates chronic inflammation. Tumor cell-derived ANGPTL2 promotes tumor invasion and angiogenesis. ANGPTL2 expression has not been fully investigated in gastric cancer (GC).

MATERIALS AND METHODS

ANGPTL2 expression in 354 patients with GC was assessed by immunohistochemistry (IHC). IHC scores were calculated, and the association of ANGPTL2 with clinicopathological factors and patient outcomes was evaluated.

RESULTS

Immunoreactive ANGPTL2 protein was expressed mainly in GC cell cytoplasm. Kaplan-Meier analysis showed that high expression of ANGPTL2 indicated significantly poorer overall disease-free survival (DFS). Among patients with curatively resected GC, multivariate analysis for DFS revealed that high ANGPTL2 expression (p<0.01), advanced T-stage (p=0.015), lymph node metastasis (p<0.01), and advanced Unio Internationalis Contra Cancrum (UICC) stage (p<0.01) were independent risk factors for poor DFS.

CONCLUSION

High cytoplasmic ANGPTL2 expression in GC tissue was associated with tumor progression, invasion, metastasis, and poor prognosis. ANGPTL2 may be a useful marker for detecting early postoperative recurrence in patients with GC.

Abstract 3411: MicroRNA-503 promotes tumor progression and acts as a novel biomarkers for early recurrence and poor prognosis in human colorectal cancer

Background:

MicroRNA (miRNA)-503 is known to be down-regulated in several types of cancer, including oral, hepatocellular, gastric, and endometrial, suggesting that it plays a tumor-suppressor role in carcinogenesis. In contrast, other recent reports have demonstrated up-regulation of miR-503 in adrenocortical carcinoma, parathyroid carcinoma, and retinoblastoma, compared with adjacent normal tissues. Collectively, miR-503 shows tissue- or disease-specific expression patterns. However, to the best of our knowledge, miR-503 expression pattern, its clinical significance and molecular mechanism in colorectal cancer (CRC) have not been investigated.

Materials and Methods:

We analyzed miR-503 expression in a subset of 69 tissue samples from normal colonic mucosa (n = 20), adenoma (n = 29) and CRC (n = 20). Next, we further quantified miR-503 expression in a larger, independent cohort, which included CRC tissues from 181 patients, and investigated the clinical significance of miR-503 in CRC. In addition, CRC cell lines were transfected with anti-miR against miR-503 for the assessment of its function.

Results:

MiR-503 expression stepwise increased according to adenoma-carcinoma sequence, and its expression in adenoma and CRC was significantly higher than that in normal colonic mucosa, respectively (adenoma: p = 0.001, CRC: p&lt;0.0001). MiR-503 expression gradually increased according to TNM stage. High expression in CRC were significantly associated with large tumor size (&gt;40mm), high grade of T stage (T3/4), lymphatic and venous invasion positive and lymph node metastasis. In addition, Kaplan Meier survival curves revealed that the CRC patients with high miR-503 expression were significantly poorer disease free survival (DFS) and overall survival (OS) than that with low expression, respectively (DFS: p = 0.01, OS: p = 0.003). Our in vitro study demonstrated that attenuated miR-503 expression resulted in inhibition of proliferation, invasion and migration capacity of CRC cell lines and acquiring capacity of anoikis.

Conclusions:

We, for the first time, demonstrated that miR-503 in CRC acts as onco-miRNAs that is supported by several evidences from our in vitro analysis and clinical data. MiR-503 is significantly associated with malignant potential of CRC and can be biomarkers for predicting early recurrence and poor prognosis in patients with CRC.

Citation Format: Yuji Toiyama, Takahito Kitajima, Hiroki Imaoka, Mikio Kawamura, Hiroyuki Fujikawa, Junichiro Hiro, Susumu Saigusa, Minako Kobayashi, Toshimitsu Araki, Masaki Ohi, Koji Tanaka, Yasuhiro Inoue, Yasuhiko Mohri, Masato Kusunoki. MicroRNA-503 promotes tumor progression and acts as a novel biomarkers for early recurrence and poor prognosis in human colorectal cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3411. doi:10.1158/1538-7445.AM2015-3411

Abstract 1061: Clinico-pathological significance of LINE-1 and ESR1 methylation levels in sporadic colorectal cancer

Background: Epigenetic changes including the global DNA methylation and the site-specific CpG island promoter methylation have been proposed to play an important role in colorectal carcinogenesis. The long interspersed nucleotide element-1 (LINE-1) methylation is good indicator of global DNA methylation levels, which is known to be hypo methylation in sporadic colorectal cancer (CRC). The promoter region of estrogen receptor 1 (ESR1) has been shown to be highly methylated in CRC compared to normal colorectal mucosa, and to be methylated in normal colorectal mucosa in an age-dependent manner. However, clinico-pathological significance of LINE-1 and ESR1 methylation levels in CRC has not sufficiently been investigated.

Aim: The aim of this study was to investigate the association between LINE-1 and ESR1 methylation levels and clinico-pathological findings including with microsatellite instability (MSI), KRAS and BRAF mutations, and tumor-infiltrating lymphocytes (TILs) in CRC.

Materials and Methods: We quantified the LINE-1 and ESR1 methylation levels in CRC (n = 182), adjacent normal mucosa (AN) (n = 18), normal colon mucosa (N) (n = 18) using a bisulfite pyrosequencing analysis. MSI status was determined using five mononucleotide-repeat microsatellite markers. KRAS (exons 2 and 3) and BRAF (V600E) mutations were also analyzed by a bisulfite pyrosequencing. TILs were evaluated by counting numbers of intra-tumor Foxp3- and CD8-positive T cell by immunohistochemistry.

Results: LINE-1 methylation levels in CRC were significantly lower than in AN or N, respectively. Lower LINE-1 methylation levels were significantly correlated with differentiated cell types, microsatellite stable (MSS) and low TILs in CRC. However, no significant association between LINE-1 methylation levels and tumor progression including with prognostic outcome was recognized. On the other hand, ESR1 methylation levels in CRC were significantly higher than in AN or N, respectively. Higher methylation levels of ESR1 were significantly associated with MSS and KRAS mutation in CRC. Although ESR1 methylation levels were not associated with tumor progression in CRC, survival curves showed that CRC patients with low ESR1 methylation levels had significantly poorer overall survival and disease free survival than those with high methylation levels. Furthermore, ESR1 methylation levels were independent indicators for poor prognosis and early recurrence of CRC patients.

Conclusion: We demonstrated novel evidence of ESR1 methylation levels as promising biomarkers for prognosis and predictive recurrence in patients with CRC.

Citation Format: Tomofumi Noguchi, Yuji Toiyama, Koichiro Mori, Shozo Ide, Hiroki Imaoka, Hiroyuki Fujikawa, Junichiro Hiro, Susumu Saigusa, Minako Kobayashi, Masaki Ohi, Koji Tanaka, Yasuhiro Inoue, Yasuhiko Mohri, kenichiro ishii, Masato Kusunoki. Clinico-pathological significance of LINE-1 and ESR1 methylation levels in sporadic colorectal cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1061. doi:10.1158/1538-7445.AM2015-1061

Preoperative prediction of peritoneal metastasis in gastric cancer as an indicator for neoadjuvant treatment

AIM

The aim of the present study was to investigate whether serum markers and clinical factors could be used for preoperative prediction of peritoneal metastasis in gastric cancer (GC) as an indicator for neoadjuvant treatment.

PATIENTS AND METHODS

We enrolled 493 patients with GC for whom preoperative serum tumor markers [carcinoembryonic antigen (CEA) and carbohydrate antigen (CA)19-9], systemic inflammatory marker C-reactive protein (CRP), host immune markers [neutrophil and lymphocyte counts and their ratio (NLR)], albumin as a nutritional marker, and objective preoperative clinical factors were available as indicators of postoperative peritoneal metastasis.

RESULTS

Specific clinical factors, including tumor size, histopathology of biopsy sample, and tumor morphology, were significantly correlated with peritoneal metastasis. CA19-9, lymphocyte count and NLR were also predictive factors for peritoneal metastasis. Multivariate analysis identified the clinical factors tumor morphology and histopathology, and laboratory markers CA19-9 and lymphocyte count as independent factors predictive for peritoneal metastasis. A combination of independent predictive factors achieved high predictive accuracy (0.882) for peritoneal metastasis preoperatively.

CONCLUSION

A combination of specific factors is an alternative method to preoperatively discriminate patients with GC with peritoneal metastasis from those without.

A report from the 2013 international symposium: the evaluation of the effects of low-dose radiation exposure in the life span study of atomic bomb survivors and other similar studies

The RERF International Low-Dose Symposium was held on 5-6 December 2013 at the RERF campus in Hiroshima, Japan, to discuss the issues facing the Life Span Study (LSS) and other low-dose studies. Topics included the current status of low-dose risk detection, strategies for low-dose epidemiological and statistical research, methods to improve communication between epidemiologists and biologists, and the current status of radiological studies and tools. Key points made by the participants included the necessity of pooling materials over multiple studies to gain greater insight where data from single studies are insufficient; generating models that reflect epidemiological, statistical, and biological principles simultaneously; understanding confounders and effect modifiers in the current data; and taking into consideration less studied factors such as the impact of dose rate. It is the hope of all participants that this symposium be used as a trigger for further studies, especially those using pooled data, in order to reach a greater understanding of the health effects of low-dose radiation.

Serum Angiopoietin-like Protein 2 Improves Preoperative Detection of Lymph Node Metastasis in Colorectal Cancer

AIM

We investigated whether serum markers and clinical factors could be used to preoperatively predict lymph node (LN) metastasis in colorectal cancer (CRC).

PATIENTS AND METHODS

The present study enrolled 157 curative CRC patients for whom preoperative serum carcinoembryonic antigen (CEA), systemic inflammatory markers (C-reactive protein (CRP) and angiopoietin-like protein 2 (ANGPTL2)) and objective preoperative clinical factors were available as indicators of pathological LN status.

RESULTS

Specific clinical factors, including gender, tumor size, histopathology of biopsy sample and tumor morphology, were significantly correlated with LN metastases. Additionally, CEA, CRP and ANGPTL2 levels were also predictive factors for LN status. Multivariate analysis revealed that clinical factors, including gender, histopathology, tumor morphology and ANGPTL2, were identified as independent predictive factors for LN metastases. A combination of clinical factors reached high predictive accuracy of LN metastases and, combined with clinical factors, ANGPTL2 further improved the accuracy.

CONCLUSION

Serum ANGPTL2 improves preoperative detection of LN metastasis in CRC.

Efficacy and safety of laparoscopic surgery in elderly patients with colorectal cancer

Colorectal cancer (CRC) is predominantly a disease of the elderly. Elderly patients may also exhibit poorer outcomes due to the increased burden of comorbidities, functional dependency and limited life expectancy. The aim of this study was to evaluate the outcome of laparoscopic surgery in elderly patients with CRC. A total of 148 patients who underwent laparoscopic surgery at our institution between January, 2000 and December, 2011 were enrolled. We compared the differences between elderly patients (aged >75 years, n=48) and non-elderly patients (aged <75 years, n=100) and evaluated the demographics and disease-related operative and prognostic data. Postoperative complications occurred in 24 (16.2%) of the 148 patients. The American Society of Anesthesiologists score and comorbidity were found to be significantly correlated with complications and the multivariate analysis demonstrated that pulmonary disease, but not age, was an independent factor affecting postoperative complications (odds ratio = 3.21, 95% confidence interval: 1.02-10.14, P=0.0470). Patients with pulmonary comorbidities also exhibited similar rates of postoperative complications compared with 259 matched patients who underwent open surgery during same period (41.2 vs. 46.7%, respectively; P=0.7547). In conclusion, chronological age alone should not be considered a contraindication for laparoscopic surgery for CRC in elderly patients. In addition, selection criteria for laparoscopic CRC surgery in elderly as well as non-elderly patients should include pulmonary comorbidities.

MicroRNA-503 promotes tumor progression and acts as a novel biomarker for prognosis in oesophageal cancer

AIM

This study investigated microRNA (miR)-503 expression levels and evaluated its clinical significance in patients with oesophageal cancer (EC).

MATERIALS AND METHODS

miR-503 expression was quantified by quantitative reverse transcription-polymerase chain reaction in 49 EC tissue samples and 12 adjacent normal tissues from 49 patients with EC. The association between miR-503 expression and clinicopathological factors, including prognostic outcomes, were assessed.

RESULTS

miR-503 was found up-regulated in EC tissues compared to adjacent normal tissues. High miR-503 expression was significantly associated with large tumor size. Kaplan-Meier analysis showed that patients with high miR-503 expression had significantly poorer disease-free and overall survival than those with lower expression levels. High miR-503 expression was identified as an independent prognostic predictor in patients with EC according to multivariate analysis.

CONCLUSION

miR-503 expression affects tumor cell proliferation in EC. Evaluation of miR-503 expression might thus help identify patients with EC with poor prognosis and higher risk of early recurrence.

RacGAP1 expression, increasing tumor malignant potential, as a predictive biomarker for lymph node metastasis and poor prognosis in colorectal cancer

555

Background: Rac GTPase activating protein (RacGAP) 1 plays a key role in controlling various cellular phenomena including cytokinesis, transformation and migration. Recently, the clinical significance of RacGAP1 expression has been reported in several malignancies. However, direct association between the RacGAP1 expression and colorectal cancer (CRC) has not been fully investigated. The aim of this study is to elucidate the function and clinical significance of RacGAP1 expression in CRC. Methods: The intrinsic functions of RacGAP1 in CRC cells were analyzed using small interfering RNA (siRNA). We analyzed RacGAP1 mRNA expression in surgical specimens from 193 CRC patients (Cohort 1) by real-time polymerase chain reaction. Then, we validated RacGAP1 protein expression using formalin-fixed paraffin-embedded samples from 298 CRC patients (Cohort 2) by immunohistochemistry. Finally, we evaluated the association between RacGAP1 mRNA and protein expression and clinicopathological data. Results: Reduced RacGAP1 expression by siRNA in CRC cell lines showed significantly decreased cellular proliferation, migration, and invasion. In Cohort 1, RacGAP1 expression in CRC was significantly higher than in adjacent normal mucosa, and increased according to TNM stage progression. High RacGAP1 expression in tumors was significantly associated with progression and prognosis. In Cohort 2, RacGAP1 protein was overexpressed mainly in the nuclei of CRC cells; however, its expression was scarcely observed in normal colorectal mucosa. RacGAP1 protein expression was significantly higher in CRC patients with higher T stage, vessel invasion, and lymph node and distant metastasis. Increased expression of RacGAP1 protein was significantly associated with poor disease-free and overall survival. Multivariate analyses revealed that high RacGAP1 expression was an independent predictive marker for lymph node metastasis, recurrence, and poor prognosis in CRC. Conclusions: Our data provide novel evidence for the biological and clinical significance of RacGAP1 as a potential biomarker for identifying patients with lymph node metastasis and poor prognosis in CRC.

Angiopoietin-like protein 2 as a novel biomarker for diagnosis and prognosis in esophageal cancer

73

Background: Angiopoietin-like protein 2 (ANGPTL2) is a secreted glycoprotein with homology to the angiopoietins and overexpression of ANGPTL2 is known to act as a causative mediator of chronic inflammatory carcinogenesis. Recently, expression in tumor cells which are associated with tumor progression has been recognized in lung, breast, colon and gastric cancer. However, to our knowledge, functional and clinical significance of ANGPTL2 expression has not been investigated in esophageal cancer (EC). Aim: We investigated the functional roles of ANGPTL2 in vitro assay and evaluated the clinical significance of ANGPTL2 expression in both primary tumor and matched serum in patients with EC. Materials and Methods: First, in vitro assays were performed for functional analysis of ANGPTL2 using small interfering RNA (siRNA). Next, ANGPTL2 expression in EC tissues was evaluated by immunohistochemically (IHC) in 71 EC patients. Finally, we investigated serum ANGPLT2 levels from EC patients (n=71) and healthy controls (n=35) by ELISA. Results: Knockdown of ANGPTL2 expression decreased proliferative, invasive and migrated capacity in EC cell lines. ANGPTL2 expression in EC tissues was significantly elevated in EC patients with high T stage, squamous cell carcinoma, and high TNM stage. Kaplan–Meier analysis showed that patients with high expression of ANGPTL2 had significantly poorer overall (p<0.01) and disease-free survival (p<0.01) than those with low expression, respectively. Furthermore, multivariate analysis revealed that high ANGPTL2 expression in EC tissues was an independent predictive marker for poor prognosis (HR: 2.30, p=0.04). On the other hands, serum ANGPTL2 levels in EC patients was significantly elevated compared to healthy controls (p<0.001), and it can discriminate EC patients from healthy controls with high accuracy (AUC=0.913). However, no significant association between serum ANGPTL2 levels and clinicopathological findings were recognized in EC patients. Conclusions: We have demonstrated several novel evidences for biological and clinical significance of ANGPTL2 in EC. This study indicates ANGPTL2 had the potential to be useful as a biomarker in EC.

Comprehensive analysis of predictive biomarkers for patients with curative colorectal cancer patients and high risk of recurrence

607

Background: Preoperative serum systemic inflammatory response (SIR) has been reported in patients with various cancers including colorectal cancer (CRC) as predictive biomarker of early recurrence. Molecular phenotypes of CRC including microsatellite instability (MSI) status and tumor infiltrating lymphocytes (TILs) have also known to be associated with recurrence in curative CRC patients. We comprehensively evaluated SIR status, MSI status and TILs in curative CRC patients and investigated which can be promising as high risk markers of recurrence in these patients. Methods: This retrospective study enrolled 157 CRC patients with stage I-III undergoing curative operation for whom preoperative neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR) and CRP were available as indicators of SIR status. For analysis of molecular phenotypes, we evaluated TILs by counting the number of intra-tumor Foxp3 and CD8 positive T cells by IHC analysis. Next, MSI status was determined in using 5 mononucleotide repeat microsatellite markers. Finally, we investigated the impact of SIR status, TILs and MSI status on the recurrence of these patients. Results: This study included a total of 90 males and 67 females, with an average age of 66.9 years. Twenty-nine patients (18.4%) developed recurrence. Kaplan-Meier analysis using SIR indicators revealed that patients with high CRP, NLR and PLR levels were significantly poorer disease free survival (DFS) than those with low levels. Low infiltrating CD8-positive T cells were significantly predictive factors for poor DFS, but there was no correlation between MSI status and recurrence, In univariate analysis, low infiltrating CD8-positive T cells, high CEA, CRP, NLR and PLR levels in serum were significantly predictive factors for poor DFS, respectively. Multivariate analysis showed that low infiltrating CD8-positive T cells and high serum CRP levels were independent predictive markers for recurrence in curative CRC patients. Conclusions: We demonstrated that evaluation of both CRP levels in preoperative serum and tumor infiltrating CD8 lymphocytes in CRC tissues are useful to predict the curative CRC patients with early relapse.

Visualization of in vivo thromboprophylactic and thrombolytic efficacy of enoxaparin in laser-induced vascular endothelial injury model using multiphoton microscopy

Enoxaparin is used postoperatively for the prevention of venous thromboembolism. In vitro studies and clinical trials have demonstrated the anticoagulant and antithrombotic efficacy of enoxaparin. In this study, we visualised thromboprophylactic and thrombolytic efficacy of enoxaparin in a laser-induced thrombus formation model in vivo using two-photon laser-scanning microscopy (TPLSM). Thrombus was induced by the selective irradiation of vascular endothelium in arterioles of the cecum of green fluorescent protein transgenic mice. The thromboprophylactic and thrombolytic efficacy of enoxaparin was visualised in vivo real-time using TPLSM. Platelet adhesion, aggregation, and platelet-dependent thrombus formation were observed in the laser-induced thrombus formation model with reproducibility. Laser-induced thrombus formation was significantly inhibited by enoxaparin pretreatment as the thromboprophylactic agent, as compared with control. The mean thrombus volumes were 652 microcubic meters in mice pretreated with enoxaparin and 8906 microcubic meter in control mice. Enoxaparin reduced the volume of laser-induced thrombus when using it as a thrombolytic agent. The mean rate of reduction was 59 percent. In a lipopolysaccharide-induced sepsis model, thromboprophylactic efficacy of enoxaparin was also observed in vivo in real-time. In vivo thromboprophylactic and thrombolytic efficacy of enoxaparin can be visualised at the single platelet level in the laser-induced endothelium injury model using TPLSM.

Angiopoietin-Like Protein 2 Acts as a Novel Biomarker for Diagnosis and Prognosis in Patients with Esophageal Cancer

BACKGROUND

Angiopoietin-like protein 2 (ANGPTL2) mediates chronic inflammation. Tumor cell-derived ANGPTL2 promotes tumor invasion and angiogenesis. Overexpression of ANGPTL2 in tumor cells is associated with tumor progression and has been recognized in lung, breast, colon, and gastric cancer. However, to our knowledge the functional and clinical significance of ANGPTL2 expression has not been investigated in patients with esophageal cancer (EC).

METHODS

First, in vitro assays were performed for functional analysis of ANGPTL2 using small interfering RNA. Next, ANGPTL2 expression in EC tissues (n = 71) was evaluated by immunohistochemistry (IHC in patients with EC (n = 71). Finally, serum ANGPLT2 levels from patients with EC (n = 71) and healthy controls (n = 35) were evaluated using enzyme-linked immunosorbent assay.

RESULTS

Knockdown of ANGPTL2 expression decreased the proliferative, invasive, and migration capacity in EC cell lines. ANGPTL2 expression in EC tissues was significantly elevated in patients with a high T stage, squamous cell carcinoma, and high TNM stage. Patients with high ANGPTL2 expression had significantly poorer overall and disease-free survival than those with low expression. Furthermore, high ANGPTL2 expression in EC tissues was an independent predictive marker for a poor prognosis. On the other hand, the serum ANGPTL2 level in patients with EC was significantly higher than that in healthy controls, and allowed for highly accurate discrimination between patients with and without EC. However, no significant association between serum ANGPTL2 levels and clinicopathological findings was observed in patients with EC.

CONCLUSIONS

We have demonstrated novel evidence for the clinical significance of ANGPTL2 as a biomarker in patients with EC.

RacGAP1 expression, increasing tumor malignant potential, as a predictive biomarker for lymph node metastasis and poor prognosis in colorectal cancer

Rac GTPase-activating protein (RacGAP) 1 plays a key role in controlling various cellular phenomena including cytokinesis, transformation, invasive migration and metastasis. This study investigated the function and clinical significance of RacGAP1 expression in colorectal cancer (CRC). The intrinsic functions of RacGAP1 in CRC cells were analyzed using small interfering RNA (siRNA). We analyzed RacGAP1 mRNA expression in surgical specimens from 193 CRC patients (Cohort 1) by real-time PCR. Finally, we validated RacGAP1 protein expression using formalin-fixed paraffin-embedded samples from 298 CRC patients (Cohort 2) by immunohistochemistry. Reduced RacGAP1 expression by siRNA in CRC cell lines showed significantly decreased cellular proliferation, migration and invasion. In Cohort 1, RacGAP1 expression in CRC was significantly higher than in adjacent normal mucosa and increased according to tumor node metastasis stage progression. High RacGAP1 expression in tumors was significantly associated with progression and prognosis. In Cohort 2, RacGAP1 protein was overexpressed mainly in the nuclei of CRC cells; however, its expression was scarcely observed in normal colorectal mucosa. RacGAP1 protein expression was significantly higher in CRC patients with higher T stage, vessel invasion and lymph node and distant metastasis. Increased expression of RacGAP1 protein was significantly associated with poor disease-free and overall survival. Multivariate analyses revealed that high RacGAP1 expression was an independent predictive marker for lymph node metastasis, recurrence and poor prognosis in CRC. Our data provide novel evidence for the biological and clinical significance of RacGAP1 as a potential biomarker for identifying patients with lymph node metastasis and poor prognosis in CRC.

In vivo optical pathology of paclitaxel efficacy on the peritoneal metastatic xenograft model of gastric cancer using two-photon laser scanning microscopy

BACKGROUND

We previously visualized in vivo responses to chemotherapy in a colorectal liver metastatic xenograft model using in vivo real-time and time-series intravital two-photon laser scanning microscopy (TPLSM). In this study, we established the method for evaluating the response of peritoneal xenografts to chemotherapy of metastatic gastric cancer using intravital TPLSM.

METHODS

Red fluorescent protein-expressing gastric cancer cells (NUGC4) were inoculated into the peritoneal cavity of green fluorescent protein nude mice.

RESULTS

Laparotomy revealed that 2 weeks after inoculation, macroscopic peritoneal metastatic nodules were formed. The first intravital TPLSM session revealed that they were composed of red tumor cell clusters and green surrounding stroma. Paclitaxel was administered intraperitoneally after the first TPLSM three times a week for 7 days in the treatment group. At the second laparotomy, there were significantly fewer and smaller nodules in the treated mice than in the controls. The second intravital TPLSM session showed tumor cell fragmentation, swelling, and nuclear condensation in the metastatic nodules--a response to chemotherapy. There were multinuclear tumor cells in the paclitaxel-treated living mice.

CONCLUSIONS

Our method may become a powerful tool for evaluating the efficacy of novel anti-gastric cancer drugs in a preclinical murine model with minimum interindividual variation.

Aortoduodenal syndrome in a patient receiving maintenance haemodialysis

An 83-year-old man receiving maintenance haemodialysis presented with abdominal pain, fever and emesis. He was initially diagnosed with acute cholecystitis. His pain and fever improved with fasting and antibiotics, but he continued to suffer from anorexia and emesis. Enhanced abdominal CT scan showed evidence of superior mesenteric artery (SMA) syndrome versus obstruction of the third part of the duodenum caused by abdominal aortic aneurysm (AAA), the so-called aortoduodenal syndrome. An upper gastrointestinal contrast study revealed duodenal dilation and blockage of the third part of the duodenum. The AAA continued to enlarge over the subsequent 3 months and the intra-abdominal visceral fat volume decreased over 1 month. The aortomesentric angle and distance remained within normal ranges. Ultimately, the patient was diagnosed with aortoduodenal syndrome. In the present case, a duodenal obstruction was caused by the combination of an enlarged AAA and reduced intra-abdominal visceral fat in a patient receiving maintenance haemodialysis.

Preoperative C-reactive protein and operative blood loss predict poor prognosis in patients with gastric cancer after laparoscopy-assisted gastrectomy

INTRODUCTION

The aim of this study was to clarify the factors associated with postoperative complications and prognoses following laparoscopy-assisted gastrectomy for gastric cancer.

METHODS

A total of 214 patients who underwent laparoscopy-assisted gastrectomy for gastric cancer were enrolled in this retrospective study. Factors that were potentially associated with postoperative complications and prognosis were assessed using the following clinical and perioperative parameters: the Estimation of Physiologic Ability and Surgical Stress scoring system, the Prognostic Nutritional Index, and the Clavien-Dindo classification.

RESULTS

Postoperative complications developed in 18.7% of patients. Blood loss ≥ 1% of body weight was significantly correlated with anastomotic leakage (P = 0.0108). Severe complications, based on the Clavien-Dindo classification, were more frequent in patients with proximal or total gastrectomies (P = 0.0324). A preoperative C-reactive protein level > 0.5 mg/dL, blood loss > 1% of body weight, age ≥ 70 years at the time of operation, and an Estimation of Physiologic Ability and Surgical Stress score ≥ 0.2 were significantly correlated with poor prognosis. Multivariate analysis revealed that two of these factors, preoperative C-reactive protein level ≥ 0.5 mg/dL and operative blood loss ≥ 1% of body weight, were independent prognostic factors (P = 0.0376 and P = 0.0112, respectively). The Prognostic Nutritional Index had no significant correlation with prognosis or the occurrence of postoperative complications.

CONCLUSION

Operative blood loss ≥ 1% of body weight and type of resection were associated with an increased frequency of postoperative complications, while preoperative C-reactive protein levels and operative blood loss may be prognostic predictors for gastric cancer patients following laparoscopy-assisted gastrectomy.

Elevated serum angiopoietin-like protein 2 correlates with the metastatic properties of colorectal cancer: a serum biomarker for early diagnosis and recurrence

PURPOSE

Angiopoietin-like protein 2 (ANGPTL2) is a mediator of chronic inflammation and inflammatory carcinogenesis. The biologic and clinical significance of ANGPTL2 remains unknown in human cancer. Therefore, we investigated the function of ANGPTL2 and evaluated its clinical significance in both primary tumors and matched sera in patients with colorectal cancer.

EXPERIMENTAL DESIGN

A colorectal cancer cell line was transfected with siRNA against ANGPTL2 for the assessment of its function. We examined ANGPTL2 expression in colorectal cancer tissues (n = 195) by immunohistochemistry. Finally, we screened serum ANGPTL2 levels from 32 colorectal cancers and 23 normal controls (NC), and validated these results in serum samples obtained from 195 colorectal cancers and 45 NCs by ELISA.

RESULTS

Knockdown of ANGPTL2 in vitro significantly inhibited cell proliferation, migration, and invasion, whereas it enhanced anoikis. ANGPTL2 was overexpressed in colorectal cancer tissues, and was significantly associated with advanced T stage, lymph node, and liver metastasis. Likewise, serum ANGPTL2 levels in colorectal cancers were significantly higher than NCs (P < 0.01), and allowed distinguishing of colorectal cancers from NCs with high accuracy (AUC = 0.837). The subsequent validation step confirmed that serum ANGPTL2 levels in colorectal cancers were significantly higher than in NCs (P < 0.0001), and had a high AUC value (0.885) for distinguishing colorectal cancers from NCs. High serum ANGPTL2 was significantly associated with advanced T stage, lymph node and liver metastasis, early relapse, and poor prognosis in colorectal cancers.

CONCLUSION

Serum ANGPTL2 is a novel diagnostic and recurrence-predictive biomarker in patients with colorectal cancer.

Short- and long-term outcomes of laparoscopic gastrectomy in elderly patients with gastric cancer

BACKGROUND

Elderly patients are regarded as being at increased risk during major abdominal surgery because of a lack of functional reserve and an increased number of comorbidities. The aim of this study was to compare short- and long-term outcomes of laparoscopic gastrectomy between elderly and young gastric cancer patients.

METHODS

Two-hundred ten patients who underwent laparoscopic gastrectomy for gastric cancer at our institution between January 2001 and December 2011 were included in this retrospective study. Patients were divided into two age groups (younger than 70 years and older than 70 years) and were evaluated with respect to postoperative morbidity, quality of life (QOL), and survival.

RESULTS

Postoperative morbidity was similar in elderly and young groups (18.3 vs. 21.6 %; P = 0.718). Overall survival of the elderly group was significantly worse than that of the young group (P < 0.001). However, disease-specific survival was not significantly different between the two groups. Longitudinal postoperative change in QOL in the elderly group showed a recovery similar to that in the young group.

CONCLUSIONS

Laparoscopic gastrectomy can be performed as safely in elderly patients as in young patients, with comparable postoperative results and long-term outcomes, including QOL, although the life expectancy of elderly patients is shorter.

Metastasis-associated long non-coding RNA drives gastric cancer development and promotes peritoneal metastasis

The prognosis of gastric cancer (GC) patients with peritoneal dissemination remains poor, and a better understanding of the underlying mechanisms is critical for the development of new treatments that will improve survival in these patients. This study aimed to clarify the clinical and biological role of two key metastasis-associated long non-coding RNAs (lncRNAs) in GC. We analyzed the expression levels of two lncRNAs-Metastasis-Associated Lung Adenocarcinoma Transcript 1 (MALAT1) and HOX-Antisense Intergenic RNA (HOTAIR)-by real-time reverse transcription PCR in 300 gastric tissues (150 GC and 150 adjacent normal mucosa), and in seven GC cell lines. Functional characterization for the role of HOTAIR in GC was performed by small interfering RNA (siRNA) knockdown, followed by series of in-vitro and in-vivo experiments. Expression of both lncRNAs was significantly higher in cancerous tissues than in corresponding normal mucosa, and higher expression of these lncRNAs significantly correlated with peritoneal metastasis in GC patients. In addition, elevated HOTAIR expression emerged both as an independent prognostic and risk factor for peritoneal dissemination. SiRNA knockdown of HOTAIR in GC cells significantly inhibited cell proliferation, migration and invasion, but concurrently enhanced the anoikis rate in transfected cells. In an in vivo assay, HOTAIR siRNA-transfected MKN45 cells injected into nude mice inhibited the growth of xenograft tumors and peritoneal metastasis compared with controls. Our data provide novel evidence for the biological and clinical significance of HOTAIR expression as a potential biomarker for identifying patients with peritoneal metastasis, and as a novel therapeutic target in patients with gastric neoplasia.

Vasohibin-1 increases the malignant potential of colorectal cancer and is a biomarker of poor prognosis

BACKGROUND

Vasohibin-1 (VASH1) is related to angiogenesis and poor prognosis in several types of cancers. However, the biological function and clinical significance of VASH1 in colorectal cancer (CRC) are not fully known.

MATERIALS AND METHODS

The associations between VASH1 expression and clinicopathological features were investigated by immunohistochemistry in 429 CRC tissues. To evaluate the function of VASH1 in vitro, small-interfering VASH1-targeting RNA was transfected into human CRC cell lines.

RESULTS

We found that VASH1 was highly expressed in the cytoplasm of CRC tissues. High VASH1 expression in the cytoplasm was significantly associated with tumor progression, such as larger tumor size, advanced T-stage, lymph node metastasis, distant metastasis and poor prognosis. Moreover, a significant positive correlation was detected between VASH1 expression and microvessel density. VASH1 siRNA inhibited CRC cell proliferation, migration, and invasion, and promoted anoikis.

CONCLUSION

Overexpression of VASH1 in CRC cells increased malignant potential and promoted metastasis.