j o u r n a l o f s u r g i c a l r e s e a r c h 1 9 3 ( 2 0 1 5 ) 7 6 4 e7 7 1
Available online at www.sciencedirect.com
ScienceDirect journal homepage: www.JournalofSurgicalResearch.com
The comparison of miR-155 with computed tomography and computed tomography plus serum amyloid A protein in staging rectal cancer Yun Yang, MD,a Tian Tang, MD, PhD,b Wei Peng, MD, PhD,c Lin Xia, MD, PhD,a Xiaodong Wang, MD,a Baofeng Duan, MD,d and Ye Shu, MD, PhDa,* a
Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China b Department of Hepatic Surgery and Hepatic Transplantation Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan Province, China c Department of Gynecology and Obstetrics, West China Women’s and Children’s Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan Province, China d Department of Oncology, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China
article info
abstract
Article history:
Background: Recently identified class of microRNAs (miRNAs) provided a new insight in
Received 6 May 2014
cancer research. As a member of miRNAs family, miR-155 expression demonstrated the
Received in revised form
correlation with tumor stage. Thus, its expression level can be potentially used for staging
17 August 2014
rectal tumors. The aim of this study was to systematically evaluate the potential abilities of
Accepted 22 August 2014
miR-155 in preoperatively N staging.
Available online 27 August 2014
Materials and methods: Expression of miR-155 was detected and quantitated in rectal cancer tissues and in adjacent nonmalignant tissues from 40 patients by TaqMan MicroRNA assays.
Keywords:
Preoperative enhanced computed tomography (CT) scan, serum amyloid A protein (SAA),
Rectal cancer
carcinoembryonic antigen (CEA), and postoperative pathologic biopsy were performed.
N stage
Results: A significant overexpression of miR-155 was observed in rectal carcinoma tissues
CT
(0.137 0.095 versus 0.093 0.091, P ¼ 0.043). High expression of miR-155 in N1e2
SAA
(0.09 0.038 versus 0.183 0.111, P ¼ 0.001) and III and IV stages (0.091 0.039 versus
miR-155
0.178 0.111, P ¼ 0.002) presented its potential correlation with N and tumor-node-
microRNA
metastasis combined stages. Receiver operating characteristics curve analysis showed that miR-155 could discriminate N0 from N1e2 with 85.0% sensitivity and 85.0% specificity at the cutoff value of 0.125. miR-155 and CT had nearly equal performances in sensitivity (0.850 versus 0.700, P ¼ 0.450) and specificity (0.850 versus 0.550, P ¼ 0.077) in predicting N1e2 stage. Compared with CT þ SAA, miR-155 had similar sensitivity (0.850 versus 0.950, P ¼ 0.617) but higher specificity (0.750 versus 0.200, P ¼ 0.015) for lymph node assessment. Conclusions: Increase in the expression of miR-155 might represent a potential valuable marker for rectal carcinoma N and combined tumor-node-metastasis staging. ª 2015 Elsevier Inc. All rights reserved.
* Corresponding author. Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, No.37 Guo Xue Lane, Chengdu 610041, Sichuan Province, China. Tel.: þ86 028 85422480; fax:þ86 028 87560976. E-mail address: [email protected] (Y. Shu). 0022-4804/$ e see front matter ª 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jss.2014.08.040
765
j o u r n a l o f s u r g i c a l r e s e a r c h 1 9 3 ( 2 0 1 5 ) 7 6 4 e7 7 1
1.
Introduction
Rectal carcinoma (RC) is one of the leading causes of cancerrelated death worldwide [1]. It is associated with a significantly high local and distant recurrence rate. For those patients with locally advanced cancer, preoperative chemoradiotherapy is regarded as preferred treatment, given that it is associated with a superior overall compliance rate, an improved rate of local control, reduced toxicity, and an increased rate of sphincter preservation in patients with low-lying tumors [2]. With increasing use of preoperative optimal treatment strategy in patients with rectal cancer, accurate local staging information is paramount for stratifying patients who would benefit from neoadjuvant therapy. At present, several modalities exist for the preoperative staging of rectal cancer such as computed tomography (CT), magnetic resonance imaging (MRI) and transrectal ultrasonography (TRUS). However, there is a wide variation of accuracy in detecting metastatic node by CT (22%e73%), MRI (39%e75%), and TRUS (62%e87%) [3]. In previous study, a preoperative evaluation strategy combining 64 multislice spiral CT with serum amyloid A protein (SAA) was found to be effective in preoperative staging, particularly in N staging [4]. SAA, termed as acute phase protein, is a major factor in altering high-density lipoproteins metabolism during inflammation [5]. It was reported that a significant increase of SAA level in patients with colorectal cancer [6]. More recent study showed that an increased SAA level was associated with metastatic lymph nodes in rectal cancer, which indicated its potential value for preoperatively noninvasive identification of lymph nodes [4]. Besides SAA, microRNAs (miRNAs) are approximately 22 nucleotide noncoding RNA molecules and function as posttranscriptional gene regulators. miRNAs were already reported to participate in the regulation of cellular development, differentiation, proliferation, and apoptosis [7,8,9]. Recent evidences indicate that some miRNAs can function as oncogenes or tumor suppressor genes [10,11]. miR-155 is such an oncogenic miRNA, which has been found overexpressing in several types of human malignant solid tumors [12,13]. A study of miR155 expression demonstrated the correlation with N stage of colorectal cancer [14]. But the potential abilities of miR-155 in preoperative predicting N stage have never been evaluated systematically. Consequently, we compared miR-155 level detection with other two preoperative lymph node assessment strategies: enhanced CT and enhanced CT þ SAA and evaluated the feasibility of using miR-155 expression level as a marker in preoperative N staging.
2.
Materials and methods
2.1.
Inclusive and exclusive criteria
adenomatous polyposis or hereditary nonpolyposis colorectal cancer; preoperative neoadjuvant therapy; intestinal obstruction, perforation and any other acute abdomen conditions. No treatment was administered preoperatively.
2.2.
Three days before surgery, venous blood specimens from the inclusive patients were taken and sent to the Clinical Immunology Laboratory for tests. The serum SAA concentrations were measured by immunofixed time nephelometry (Dade Behring Diagnostics, Marburg, Germany). The serum carcinoembryonic antigen (CEA) concentrations were measured by radioimmunoassays kits (Roche Diagnostics, Mannheim, Germany). All detections were performed according to manufacturer’s instructions. Enhanced CT scans were performed for all patients by using a Philips Brilliance 64-slice CT scanner (Philips Medical Systems, Best, The Netherlands). The slice interval was adjusted to 5 mm. Contrast agent (Omnipaque; GE Healthcare, Buckinghamshire, United Kingdom) was administered intravenously for all patients. CT was prospectively evaluated before surgery by same radiologist, who was blind to any patient information. Metastatic nodal was considered to be present if their diameter exceeded 8 mm [15]. At the same time, the presence of regional lymph node metastases was also assessed by another collaborative strategy of enhanced CT þ SAA. Judgment standards are as follow [4] (Table 1).
2.3. Reverse transcription and quantitative polymerase chain reaction From the inclusive patients, samples of tumor tissue and adjacent nonmalignant tissue (5e10 cm away from tumor site) were collected and frozen in liquid nitrogen right after surgical resection. Same technical group measured the expressions of miRNAs in nonmalignant and tumor tissue samples. The tissue samples were labeled such as to ensure that they were blind to the nonmalignant and tumor tissue identifications. Using Trizol (ABI, Carlsbad, CA), total RNAs that contain miRNAs were isolated from tumor and nonmalignant tissue samples of the 40 patients with primary RC. miR-155, U6 snRNA, and U47-specific probes were synthesized by ABI. The whole procedure was followed according to the TaqMan MicroRNA assay protocol (4364031 Rev. E, 01/2011) of ABI. The
Table 1 e The judgment standards for preoperative N staging by enhanced CT D SAA. N stage N0 N1e2
From August to October 2012, 40 newly biopsy-proven RC patients were recruited into this study at the gastrointestinal surgery center of West China Hospital. Inclusive criteria included tumor (proximal from dentate line) under the peritoneal reflection. Exclusive criteria excluded familial
Preoperative enhanced CT scan and SAA
Standards No visible lymph node, or a lymph node (diameter
Available online at www.sciencedirect.com
ScienceDirect journal homepage: www.JournalofSurgicalResearch.com
The comparison of miR-155 with computed tomography and computed tomography plus serum amyloid A protein in staging rectal cancer Yun Yang, MD,a Tian Tang, MD, PhD,b Wei Peng, MD, PhD,c Lin Xia, MD, PhD,a Xiaodong Wang, MD,a Baofeng Duan, MD,d and Ye Shu, MD, PhDa,* a
Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China b Department of Hepatic Surgery and Hepatic Transplantation Center, West China Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan Province, China c Department of Gynecology and Obstetrics, West China Women’s and Children’s Hospital, West China Medical School, Sichuan University, Chengdu, Sichuan Province, China d Department of Oncology, West China Hospital, Sichuan University, Chengdu, Sichuan Province, China
article info
abstract
Article history:
Background: Recently identified class of microRNAs (miRNAs) provided a new insight in
Received 6 May 2014
cancer research. As a member of miRNAs family, miR-155 expression demonstrated the
Received in revised form
correlation with tumor stage. Thus, its expression level can be potentially used for staging
17 August 2014
rectal tumors. The aim of this study was to systematically evaluate the potential abilities of
Accepted 22 August 2014
miR-155 in preoperatively N staging.
Available online 27 August 2014
Materials and methods: Expression of miR-155 was detected and quantitated in rectal cancer tissues and in adjacent nonmalignant tissues from 40 patients by TaqMan MicroRNA assays.
Keywords:
Preoperative enhanced computed tomography (CT) scan, serum amyloid A protein (SAA),
Rectal cancer
carcinoembryonic antigen (CEA), and postoperative pathologic biopsy were performed.
N stage
Results: A significant overexpression of miR-155 was observed in rectal carcinoma tissues
CT
(0.137 0.095 versus 0.093 0.091, P ¼ 0.043). High expression of miR-155 in N1e2
SAA
(0.09 0.038 versus 0.183 0.111, P ¼ 0.001) and III and IV stages (0.091 0.039 versus
miR-155
0.178 0.111, P ¼ 0.002) presented its potential correlation with N and tumor-node-
microRNA
metastasis combined stages. Receiver operating characteristics curve analysis showed that miR-155 could discriminate N0 from N1e2 with 85.0% sensitivity and 85.0% specificity at the cutoff value of 0.125. miR-155 and CT had nearly equal performances in sensitivity (0.850 versus 0.700, P ¼ 0.450) and specificity (0.850 versus 0.550, P ¼ 0.077) in predicting N1e2 stage. Compared with CT þ SAA, miR-155 had similar sensitivity (0.850 versus 0.950, P ¼ 0.617) but higher specificity (0.750 versus 0.200, P ¼ 0.015) for lymph node assessment. Conclusions: Increase in the expression of miR-155 might represent a potential valuable marker for rectal carcinoma N and combined tumor-node-metastasis staging. ª 2015 Elsevier Inc. All rights reserved.
* Corresponding author. Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, No.37 Guo Xue Lane, Chengdu 610041, Sichuan Province, China. Tel.: þ86 028 85422480; fax:þ86 028 87560976. E-mail address: [email protected] (Y. Shu). 0022-4804/$ e see front matter ª 2015 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.jss.2014.08.040
765
j o u r n a l o f s u r g i c a l r e s e a r c h 1 9 3 ( 2 0 1 5 ) 7 6 4 e7 7 1
1.
Introduction
Rectal carcinoma (RC) is one of the leading causes of cancerrelated death worldwide [1]. It is associated with a significantly high local and distant recurrence rate. For those patients with locally advanced cancer, preoperative chemoradiotherapy is regarded as preferred treatment, given that it is associated with a superior overall compliance rate, an improved rate of local control, reduced toxicity, and an increased rate of sphincter preservation in patients with low-lying tumors [2]. With increasing use of preoperative optimal treatment strategy in patients with rectal cancer, accurate local staging information is paramount for stratifying patients who would benefit from neoadjuvant therapy. At present, several modalities exist for the preoperative staging of rectal cancer such as computed tomography (CT), magnetic resonance imaging (MRI) and transrectal ultrasonography (TRUS). However, there is a wide variation of accuracy in detecting metastatic node by CT (22%e73%), MRI (39%e75%), and TRUS (62%e87%) [3]. In previous study, a preoperative evaluation strategy combining 64 multislice spiral CT with serum amyloid A protein (SAA) was found to be effective in preoperative staging, particularly in N staging [4]. SAA, termed as acute phase protein, is a major factor in altering high-density lipoproteins metabolism during inflammation [5]. It was reported that a significant increase of SAA level in patients with colorectal cancer [6]. More recent study showed that an increased SAA level was associated with metastatic lymph nodes in rectal cancer, which indicated its potential value for preoperatively noninvasive identification of lymph nodes [4]. Besides SAA, microRNAs (miRNAs) are approximately 22 nucleotide noncoding RNA molecules and function as posttranscriptional gene regulators. miRNAs were already reported to participate in the regulation of cellular development, differentiation, proliferation, and apoptosis [7,8,9]. Recent evidences indicate that some miRNAs can function as oncogenes or tumor suppressor genes [10,11]. miR-155 is such an oncogenic miRNA, which has been found overexpressing in several types of human malignant solid tumors [12,13]. A study of miR155 expression demonstrated the correlation with N stage of colorectal cancer [14]. But the potential abilities of miR-155 in preoperative predicting N stage have never been evaluated systematically. Consequently, we compared miR-155 level detection with other two preoperative lymph node assessment strategies: enhanced CT and enhanced CT þ SAA and evaluated the feasibility of using miR-155 expression level as a marker in preoperative N staging.
2.
Materials and methods
2.1.
Inclusive and exclusive criteria
adenomatous polyposis or hereditary nonpolyposis colorectal cancer; preoperative neoadjuvant therapy; intestinal obstruction, perforation and any other acute abdomen conditions. No treatment was administered preoperatively.
2.2.
Three days before surgery, venous blood specimens from the inclusive patients were taken and sent to the Clinical Immunology Laboratory for tests. The serum SAA concentrations were measured by immunofixed time nephelometry (Dade Behring Diagnostics, Marburg, Germany). The serum carcinoembryonic antigen (CEA) concentrations were measured by radioimmunoassays kits (Roche Diagnostics, Mannheim, Germany). All detections were performed according to manufacturer’s instructions. Enhanced CT scans were performed for all patients by using a Philips Brilliance 64-slice CT scanner (Philips Medical Systems, Best, The Netherlands). The slice interval was adjusted to 5 mm. Contrast agent (Omnipaque; GE Healthcare, Buckinghamshire, United Kingdom) was administered intravenously for all patients. CT was prospectively evaluated before surgery by same radiologist, who was blind to any patient information. Metastatic nodal was considered to be present if their diameter exceeded 8 mm [15]. At the same time, the presence of regional lymph node metastases was also assessed by another collaborative strategy of enhanced CT þ SAA. Judgment standards are as follow [4] (Table 1).
2.3. Reverse transcription and quantitative polymerase chain reaction From the inclusive patients, samples of tumor tissue and adjacent nonmalignant tissue (5e10 cm away from tumor site) were collected and frozen in liquid nitrogen right after surgical resection. Same technical group measured the expressions of miRNAs in nonmalignant and tumor tissue samples. The tissue samples were labeled such as to ensure that they were blind to the nonmalignant and tumor tissue identifications. Using Trizol (ABI, Carlsbad, CA), total RNAs that contain miRNAs were isolated from tumor and nonmalignant tissue samples of the 40 patients with primary RC. miR-155, U6 snRNA, and U47-specific probes were synthesized by ABI. The whole procedure was followed according to the TaqMan MicroRNA assay protocol (4364031 Rev. E, 01/2011) of ABI. The
Table 1 e The judgment standards for preoperative N staging by enhanced CT D SAA. N stage N0 N1e2
From August to October 2012, 40 newly biopsy-proven RC patients were recruited into this study at the gastrointestinal surgery center of West China Hospital. Inclusive criteria included tumor (proximal from dentate line) under the peritoneal reflection. Exclusive criteria excluded familial
Preoperative enhanced CT scan and SAA
Standards No visible lymph node, or a lymph node (diameter
