Prognostic Value of Metastatic Tumoral Caveolin-1 Expression in Patients with Resected Gastric Cancer.
Gastric cancer (GC) still remains the third leading cause of cancer-related mortality, with 723,100 deaths per year . With recent advancements in our understanding of the molecular biology of GC, targeting agents for molecular targets, such as epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF) receptor, and human epidermal growth factor receptor 2 (HER2), have been used widely to improve patient survival in the setting of recurrent and metastatic GC [2, 3], but the prognosis of patients with advanced GC remains poor. Therefore, new therapeutic molecular targets are required to improve the survival of patients.
Caveolin-1 (Cav-1), a 22-kD protein of 178 amino acids and a member of the caveolin family (Cav-1, 2, and 3), is the highly conserved and essential component of caveolae . Cav-1 is expressed in the terminally differentiated cells, such as fibroblasts, adipocyte, endothelial cells, myoepithelial cells, and type I pneumocytes, but not in human peripheral blood cells or myeloid, lymphoid, and erythroid cell lines. Functionally, Cav-1 has been implicated in diverse cellular processes, including cholesterol homeostasis, vesicular transport, cell migration, cell cycle, and cell polarity, to regulate cell transformation and signal transduction. The perturbations in Cav-1 expression and/or function were, therefore, assumed to play an important part in disease pathogenesis, such as cancer [5, 6].
Dysregulation of Cav-1 has been associated with several human malignancies including GC. Several studies implicate that Cav-1 is involved in a tumor suppression in vitro and in vivo [7, 8]. In contrast, others reported an increased expression of Cav-1 in the more advanced stages of cancers [5, 9,10], which still suggest the conflicting impact on cancer progression of Cav-1 protein. These contradictory results could be due to the complex biologic behavior of Cav-1 protein, which depends on the location of this molecule and interaction of signaling pathways , which might mean the different roles between primary and metastatic tumors. Thus, to clarify the clinical role of the expression of Cav-1 protein in the curatively resected GC, we evaluated the expression of tumoral and stromal Cav-1 proteins in primary gastric tumors and metastatic lymph nodes and compared their relationship with clinicopathological parameters and clinical outcomes.
2. Materials and Methods
2.1. Patients and Specimens. The clinical and pathological data of patients with gastric cancer, who had undergone primary curative resection between 2001 and 2005 at Uijeongbu St. Mary's Hospital of the Catholic University of Korea, were reviewed. The inclusion criteria were the following: (i) pathologically confirmed diagnosis of adenocarcinoma; (ii) having performed primary R0 resection of cancer and not received radiation or chemotherapy preoperatively; (iii) having at least 15 or more the removed lymph nodes; and (iv) paraffin block of tumor specimens were available. Postoperative pathological staging was analyzed according to the American Joint Committee on Cancer staging criteria, 7th edition. This study was approved by the Institutional Research Ethics Board of Uijeongbu St. Mary's Hospital of the Catholic University of Korea and adhered to the Declaration of Helsinki.
2.2. Immunohistochemical Analysis. Immunohistochemistry was performed on formalin-fixed, paraffin-embedded tissues of all primary cancer samples and lymph nodes with cancer metastasis. For immunostaining for Cav-1, we excluded meticulously low tumor volume (<2 mm) of metastatic lymph node, so called as "micrometastasis," and selected the largest tumor volume among metastatic lymph nodes in each case. As a control, we conducted Cav-1 immunostaining on 11 normal gastric tissues. Those samples were obtained from resected gastric tissue due to gastric ulcer. Submitting samples to Cav-1 immunostain were far away from the lesion to avoid a significant inflammation. The whole tissue sections of all surgical tumor samples were deparaffinized with xylene and graded alcohols and then rehydrated with distilled water. Endogenous peroxidase was blocked by 3% hydrogen peroxide in methanol for 10 min. Antigen retrieval was then performed by heating the slides for 15 minutes in 0.01 mol/L citrate buffer (pH 6.0). The sections were incubated with human-specific antibodies against caveolin-1 (1:400, cell signaling) at room temperature for 2 hours, washed in TBST (tris buffered saline with 0.1% Tween 20), and then incubated with biotinylated secondary antibody for 10 min. After being washed with TBST, sections were stained by a streptavidin-peroxidase detection system (Novex). The immunoreaction was visualized using 3,3-diaminobenzidine as chromogen and counterstained with hematoxylin. The results were analyzed by two board certified pathologists (S.A.H. and S.H.Y), independently, who were blinded to all patients' clinical data. Expression of primary tumoral, stromal, and metastatic tumoral Cav-1 was analyzed through intensity and proportion. The staining intensity was scored semiquantitively as 0 (negative), +1 (weak), +2 (moderate), and +3 (strong). The H score (0 to 300) was calculated by multiplying intensity and proportion of Cav-1 expression. To find the best cutoff values for predicting survival, a maximally selected rank statistics test was performed, using R Maxstat Package (version 3.3.1; R Foundation for statistical Computing, Viena, Austria) . As a result, H score > 30 for primary tumoral Cav-1 expression, >120 for stromal, and any expression for metastatic tumor were determined as high expression.
2.3. Statistical Analysis. Cancer-specific survival (CSS) was calculated from the date of surgery to the date of death from GC; the observations were censored at death from causes other than GC. The relapse-free survival (RFS) duration was calculated from the date of diagnosis to the date of first distant or local disease recurrence or last follow-up. The Kaplan-Meier method was used to analyze "time-to-event" data, and the significance of differences in the cumulative survival curves was evaluated using the log-rank test. Cox proportional hazards regression models were used to investigate the significance of prognostic factors. Cav-1 expression and all variables with a P value of <0.25 in the univariate analysis were included in the multivariate analysis. Correlations between immunohistochemical profiles and clinicopathological variables were analyzed by the chi-squared or Fisher's exact test. Comparisons of immunohistochemical expression were performed with an independent-sample t-test for continuous variables. Survival rates and hazard ratios (HRs) are presented with their respective 95% confidence intervals (CIs). A P value of <0.05 was considered to indicate statistical significance. All statistical analyses were performed using the R statistical software package (R Foundation for Statistical Computing, Vienna, Austria).
3.1. Patients' Clinical Characteristics. In total, 145 paraffin blocks of tumor samples were available from patients who had undergone surgical curative gastrectomy. The clinical and pathological characteristics of the cohort are shown in Table 1. The patient cohort consisted of 107 males (73.8%) and 38 females (26.2%), with a median age of 60 (29-89) years. According to the AJCC staging criteria, twenty patients (13.8%) had stage I disease, 44 (30.3%) patients had stage II disease, and 81 (55.9%) had stage III disease. Ninety-one patients (62.8%) have regional lymph node metastases at the time of operation. Seventy-five (51.7%) patients postoperatively received 5-fluorouracil and cisplatin combination therapy. The follow-up period ranged from 0.7 to 172.2 months, with a median of 70.3 months after curative surgical resection. Of the 145 total patients, 43 (29.7%) died due to their cancer, and 102 (70.3%) were alive at the last follow-up. Disease recurrence was observed in 62 cases (42.8%).
3.2. Immunohistochemical Staining Patterns and Relationship with Clinicopathological Findings. Figure 1 shows a representative immunohistochemistry results. Cav-1 expression in the normal gastric mucosa was found in parietal cells, but not gastric foveolar epithelium. In stroma, Cav-1 expression was observed in fibroblast, blood vessel, and smooth muscle of muscularis mucosa and proper muscle layer. The result of normal gastric tissue was consistent in all 11 normal gastric tissues (Figures 1(a) and 1(b)). Of the 145 gastric specimens, Cav-1 was highly expressed in tumor cells of 18 (12.4%) cases (Figure 1(c)), while low expression was observed in 127 (87.6%) cases (Figure 1(d)). In a total of 91 cases with nodal metastasis, high expression of Cav-1 of tumor cell in metastatic lymph nodes was observed in 15 (16.5%) cases (Figure 1(e)). In metastatic lymph nodes, 76 (83.5%) cases with low Cav-1 expression were entirely negative for Cav-1 immunostaining (Figure 1(f)). In primary tumoral storma, high expression of Cav-1, which was observed in fibroblast-like cells, was demonstrated in 32 (22.7%) cases (Figure 1(e)), while low expression was found in 109 (77.3%), including loss of stromal Cav-1 expression in 57 (40.4%, Figure 1(f)). Correlation between primary tumoral, stromal, and metastatic tumoral Cav-1 expression was not identified (primary tumor versus metastatic tumor, P =1000; primary stroma versus metastatic tumor, P = 0.522). Associations between Cav-1 expression and clinicopathological features, including well-known prognostic factors such as pathologic TNM stage, lymph node metastasis, lymphovascular invasion, degree of differentiation, and Lauren classification, were also explored. High meta-static tumoral Cav-1 expression was marginally related with vascular invasion (P = 0.069), and low expression of Cav-1 in the stroma of the primary tumor was significantly related with diffuse type of Lauren classification (P = 0.045, Table 2). The lymph node ratio (LNR), which is defined as the total number of positive/total number of lymph nodes collected, also has been highlighted as an important prognostic indictor of gastric cancer after surgery . Thus, we also investigated the relation between the level of Cav-1 expression and LNR. As shown in Figure 2, mean LNR level was significantly higher in patients with gastric cancer with high metastatic tumoral Cav-1 expression (0.229 [+ or -] 0.195) compared to those with low metastatic tumoral Cav-1 expression (0.416 [+ or -] 0.255, P = 0.015).
3.3. Survival Analysis with Respect to Cav-1 Expression in Primary and Metastatic Lymph Nodes. The 5-year RFS rate and CSS rate for patients who had undergone curative resection of gastric cancer were 59.7% (95% CI, 51.8-68.7) and 69.9% (95% CI, 62.2-78.6), respectively. For RFS, univariate analysis revealed that the following factors were significantly correlated with disease relapse: advanced pT stage (P <0.001), lymph node metastasis (P <0.001), LNR (P < 0.001), lymphatic invasion (P = 0.012), and tumor grade (P = 0.046) (Table 3). Kaplan-Meier survival curve revealed inverse associations between high expression of metastatic tumoral Cav-1 protein in lymph node and disease relapse (P = 0.002), not primary tumoral or stromal Cav-1 expression (P = 0.892 and P = 0.131, resp., Figure 3(a)). In the multivariate analysis for RFS, in addition to old age, advanced pT stage, and diffuse type, metastatic tumoral Cav-1 expression was an independent indicator of poor prognosis (HR, 3.934; 95% CI, 1.882-8.224; P = 0.001, Table 3). For CSS, univariate analysis revealed that the following factors were significantly correlated with CSS: advanced pT stage (P = 0.005), lymph node metastasis (P < 0.001), LNR (P < 0.001), lymphatic invasion (P = 0.012), and venous invasion (P = 0.023). Kaplan-Meier survival curve revealed a significant association between high expression of tumoral Cav-1 protein in metastatic lymph node and cancer-specific death (P = 0.004, Figure 3(b)). In the multivariate analysis, tumoral Cav-1 protein in meta-static lymph node was found to be significantly associated with a poor outcome (HR, 2.681; 95% CI, 1.612-8.623; P = 0.002, Table 4). Furthermore, to clarify the role of Cav-1 expression in the patients with lymph node metastasis, we performed univariate and multivariate analyses for RFS and CSS in the subgroup of the patients with lymph node metastasis. Metastatic tumoral Cav-1 expression remained as a strong indicator of poor prognosis for RFS (HR, 3.136; 95% CI, 1.444-6.810; P = 0.003, Figure 3(c) and Table 5) and CSS (HR, 2.509; 95% CI, 1.078-5.837; P = 0.032, Figure 3(d) and Table 6).
The impact of Cav-1 on cancer progression, whether it is expressed in the tumor cells or stromal cells, seems to be complex and debatable [5, 8, 14-17]. Previous reports also showed a controversial role for Cav-1 expression in GC, leading us to analyze Cav-1 expression in GC [10, 15, 18]. In the present study, we found that Cav-1 expression was more frequently observed in tumor cells of metastatic lymph nodes than of primary sites and that high metastatic tumoral Cav-1 expression was associated with poor clinical outcome in the patients with resected GC, not primary tumoral or stromal Cav-1 expression. Its prognostic influence seemed to be independent of well-known clinicopathological factors. To the best of our knowledge, this is the first report focusing on clinical significance of Cav-1 in metastatic tumors in the patients with resected GC.
Cav-1 protein is a component of caveolae invaginated microdomains of the plasma membrane that is present in most mammalian cells . High tumoral Cav-1 expression was observed in GC cells in 18 of 145 cases (12.4%). In the nonepithelial compartment, Cav-1 was more frequently expressed in fibroblast-like cells, endothelial cells, and smooth muscle within the stroma surrounding tumor nests more than tumor cell, and loss of stromal Cav-1 expression was found in 57 of 141 cases (40.4%), which is consistent with the previous studies [10, 18]. In a study of 405 patients with GC, Cav-1 expression was absent in normal epithelial cells and was highly expressed in 22 (5.4%) of 405 cases . In addition, loss of stromal Cav-1 expression in cancer-associated fibroblast (CAF) was reported at 35% in GC . Similarly, Cav-1 protein was dysregulated in several other gastrointestinal cancers. Tumoral Cav-1 expression increased in cancers cells compared to their normal counterparts, whereas stromal Cav-1 expression decreased in cancer tissues compared to adjacent normal tissues, such as pancreatic cancer [9,19], esophageal cancer , and hepatocellular carcinomas . Cav-1 expression is known to be regulated mainly by inactivation of oncogenes or inactivation of tumor suppressive genes, TGF-[beta], and oxidative stress in the tumor microenvironment [22, 23].
The role of Cav-1 protein in tumorigenesis and tumor progression still remains controversial. Initially, Cav-1 protein has been shown to play a role in tumor suppression. The CAV-1 gene resides on chromosome 7q31.1, a fragile site known as FRA7G, which is commonly deleted in human cancers . Mutant mice in the gene-encoding CAV-1 showed an enhanced association with the development and progression of breast cancer carcinogenesis  and normally regulated the proliferation of intestinal stem cells in vivo . Tumor suppressive function of Cav-1 is mediated by induction of the cell cycle arrest of G0-G1-phase in fibroblasts through a p53/p21-dependent pathway , inhibition of Wnt/[beta]-catenin signaling in epithelial cell , and activation of cell-matrix interactions toward the basal membrane . However, the upregulation of Cav-1 in human cancer cells may serve as a tumor promoter role in the majority of human cancer types. Previous studies have related Cav-1 over-expression with oncogenic transformation, invasion, and metastasis. Recently, Chatterjee et al. have observed that CAV-1 knockdown reduced proliferative, invasive, and migratory properties in multiple pancreatic cancer cell lines . Cav-1 affects several signaling pathways in cellular transformation, including aerobic glycolysis, JAK/STAT, JNK, and Src signaling pathway [9, 28]. These conflicting effects may be mediated by the activation status of different domains of Cav-1, which depends on the levels of other molecules in different signaling pathways that are expressed with Cav-1 .
Notably, in a study of GC, Cav-1 mRNA expression was lower in cell lines derived from a primary tumor, but it increased in cell lines originating from distant metastases. In addition, Cav-1 overexpressing gastric cancer cell line gained prosurvival ability , which results are concordant with ours that the high Cav-1 expression of tumor cells in metastatic lymph node was related with poor prognosis of GC patients. Although primary tumoral Cav-1 over-expression was documented to associate with lymph node metastasis and advanced TNM stage in the previous study , our results suggested that primary tumoral Cav-1 expression was not correlated with these clinicopathological features and clinical outcomes, which is in consistency with Barresi et al.'s study . However, our present study showed that metastatic tumoral Cav-1 expression was related with high LNR (P = 0.015) and perivascular invasion (P = 0.069) and that its elevated expression had a strongly negative correlation with clinical prognosis, which suggest that Cav-1 protein plays a more significant role in metastatic tumor than the primary tumor. Ectopic expression of Cav-1 in GC cell lines with a low level of Cav-1 decreased proliferation but promoted anchorage-independent growth and survival. This biphasic pattern may support the different roles of Cav-1 as a tissue and stage-specific tumor modulator , where it acts as an inhibitor or promoter of tumor formation and progression depending on its protein interaction partners such as growth factor receptors or cell adhesion molecules.
In this study, regarding stromal Cav-1 expression, it was more frequently downregulated in diffuse-type (58.2%) than mixed or intestinal-type (41.8%) of Lauren classification (P = 0.045), which is consistent with the previous reports [29, 30], and stromal Cav-1 protein did not show the prognostic role in curatively resected GC. The down-regulation of Cav-1 is a major characteristic of CAFs, and existing studies have indicated that CAFs have the ability to inhibit cancer cell apoptosis, increase the growth of cancer cells, and activate tumor angiogenesis [16, 18]. Thus, the loss of stromal Cav-1 has been reported to be a poor prognostic factor in various human cancers . In previous study, low expression of Cav-1 in CAF was related with unfavorable prognosis in GC . Compared to the present study including only primary R0 resection, the patient cohort in that study was heterogeneous, in which patients who received cytoreductive surgery and postoperative radiotherapy were included. Moreover, we used whole tissue section to evaluate the expression of Cav-1, while they conducted only on tissue microarray. These factors might be contributed to the different results of prognostic impact of stromal Cav-1 expression in GC. Furthermore, the prognostic significance of Cav-1 in CAFs remains still debatable in various cancers. Goetz et al. reported that Cav-1 expression in the CAFs of breast cancer correlated with low survival and that stromal Cav-1, through p190RhoGAP regulation, favors remodels periand intratumoral microenvironments to facilitate tumor invasion, correlating with increased metastatic potency in vitro and in vivo . Vered et al., in an analysis of their series of 64 cases of tongue squamous cell carcinoma, reported that accumulation of Cav-1 in tissue microenvironment had a negative prognostic value and also showed that Cav-1 expression in fibroblasts undergoes trans-differentiation to CAFs . These conflicting results may attribute to the contradictory function of CAF in cancer progression .
The limitation of our study is that Cav-1 expression was evaluated in a part of metastatic lymph nodes. Thus, the issue was remained to represent metastatic gastric cancer. However, we excluded meticulously low tumor volume of metastatic lymph node (<2 mm), so called as "micrometastasis," and selected the largest tumor volume among the meta-static lymph nodes in each case. We believe that the meta-static lymph node in the present study could be sufficient to evaluate Cav-1 expression.
This study clearly demonstrates the complex role of Cav-1 in GC, of which metastatic tumoral expression was an independent prognostic factor for clinical outcomes, not primary tumoral expression of Cav-1. Future study will be required to determine the mechanism of Cav-1 protein, by which oncogenic signaling through this complex is regulated.
An earlier version of this work was presented as an abstract at Gastrointestinal Cancers Symposium 2017 and AACR 2017 Proceedings.
Conflicts of Interest
The authors declare that they have no competing interest.
Der Sheng Sun and Soon Auck Hong contributed equally to this project and should be considered cofirst authors.
This study was supported by an industry academic cooperation research fund from the Catholic University of Korea (Der Sheng Sun) and by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Science, ICT, and Future Planning (NRF-2015R1C1A1A01054591) (Yoon Ho Ko).
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Der Sheng Sun, (1) Soon Auck Hong, (2) Hye Sung Won, (1) Su Hyun Yoo, (3) Han Hong Lee, (4) Okran Kim, (5) and Yoon Ho Ko (1,5)
(1) Division of Oncology, Department of Internal Medicine, The Catholic University of Korea, Seoul, Republic of Korea
(2) Department of Pathology, Soonchunhyang Cheonan Hospital, Soonchunhyang University College of Medicine, Cheonan, Republic of Korea
(3) Department of Hospital Pathology, Uijeongbu St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Uijeongbu-si, Republic of Korea
(4) Department of General Surgery, The Catholic University of Korea, Seoul, Republic of Korea
(5) Cancer Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
Correspondence should be addressed to Yoon Ho Ko; firstname.lastname@example.org
Received 24 April 2017; Revised 8 June 2017; Accepted 15 June 2017; Published 30 July 2017
Academic Editor: Nicola Silvestris
Caption: FIGURE 1: Representative caveolin-1 (Cav-1) expression. In nonneoplastic gastric tissue, Cav-1 expression was detected in fibroblast (arrow) and vessel walls (arrow head) in stroma (a), while Cav-1 showed a scant expression in parietal cells in epithelium (b). Tumor cells showed high (c) and low expression (d) of Cav-1 in the stomach and high (e) and low expression (f) of metastatic lymph node. Stromal Cav-1 immunoreactivity was observed in low (g) and high (h).
Caption: FIGURE 2: Relationship between Cav-1 protein expression and lymph node ratio (LNR). Patients with a high Cav-1 metastatic tumor showed significantly higher LNR levels (0.229 [+ or -] 0.195) compared to those with low metastatic tumoral Cav-1 expression (0.416 [+ or -] 0.255, P = 0.015).
Caption: FIGURE 3: Kaplan-Meier curves for patient survival. Patients with a high Cav-1 metastatic tumor showed a significantly shorter relapse-free survival (a) and cancer-specific survival (b) after surgery than those with a low Cav-1 tumor (P = 0.002 and P = 0.004, resp.). In patients with lymph node metastasis, high metastatic tumoral Cav-1 expression was associated with shorter relapse-free survival (c) and cancer-specific survival times (d) (P = 0.002 and P = 0.005, resp.).
TABLE 1: Baseline clinicopathological characteristics of patients with gastric cancer. Characteristics No. of patients, n (%) Patient number 145 Age (years), median 60 (29-89) >60 73 (50.3) [less than or equal to] 60 72 (49.7) Gender Male 107 (73.8) Female 38 (26.2) T stage pT2-3 43 (29.7) pT4 102 (70.3) N stage pN0-1 79 (54.5) pN2-3 66 (45.5) TNM stage I 20 (13.8) II 44 (30.3) III 81 (55.9) Tumor grade Well 16 (11.0) Moderate-poor 129 (89.0) Lymphatic invasion No 27 (18.8) Yes 117 (81.2) Vascular invasion No 127 (91.4) Yes 12 (8.6) Lauren classification Nondiffuse type 68 (46.9) Diffuse type 77 (53.1) LNR, median (range) 0.071 (0-1) > median 74 (51.0) [less than or equal to] median 71 (49.0) Adjuvant therapy No 70 (48.3) Yes 75 (51.7) LNR: lymph node ratio. TABLE 2: Correlations between clinicopathologic findings and caveolin-1 expression. Primary tumoral Cav-1 expression Low, n (%) High, n (%) No. of patients 127 (87.6) 18 (12.4) TNM stage I 16 (12.6) 4 (22.2) II 38 (29.9) 6 (33.3) III 73 (57.5) 8 (44.5) P value 0.431 Tumor grade Well 15 (11.8) 1 (5.6) Moderately-poorly 112 (88.2) 17 (94.4) P value 0.694 Lymphatic invasion No 22 (17.5) 5 (27.8) Yes 104 (82.5) 13 (72.2) P value 0.333 Vascular invasion No 110 (90.9) 17 (94.4) Yes 11 (9.1) 1 (5.6) P value 1 Lauren classification Nondiffuse type 60 (47.2) 8 (44.4) Diffuse type 67 (52.8) 10 (55.6) P value 1 Stromal Cav-1 expression Low, n (%) High, n (%) No. of patients 109 (77.3) 32 (22.7) TNM stage I 16 (14.7) 4 (12.5) II 33 (30.3) 9 (28.1) III 60 (55.0) 19 (59.4) P value 0.960 Tumor grade Well 9 (8.3) 6 (18.8) Moderately-poorly 100 (91.7) 26 (81.2) P value 0.106 Lymphatic invasion No 21 (19.4) 6 (18.8) Yes 87 (80.6) 26 (81.2) P value 1 Vascular invasion No 95 (92.2) 28 (87.5) Yes 8 (7.8) 4 (12.5) P value 0.478 Lauren classification Nondiffuse type 46 (41.8) 20 (62.5) Diffuse type 63 (58.2) 12 (37.5) P value 0.045 * Metastatic tumoral Cav-1 expression Low, n (%) High, n (%) No. of patients 76 (83.5) 15 (16.5) TNM stage I 1 (1.3) 0 (0) II 10 (13.2) 3 (20.0) III 65 (85.5) 12 (80.0) P value 0.540 Tumor grade Well 3 (3.9) 1 (6.7) Moderately-poorly 73 (96.1) 14 (93.3) P value 0.520 Lymphatic invasion No 4 (5.3) 0 (0) Yes 72 (94.7) 15 (100) P value 1 Vascular invasion No 67 (90.3) 10 (71.4) Yes 7 (9.70) 4 (28.6) P value 0.069 Lauren classification Nondiffuse type 29 (37.8) 9 (60.0) Diffuse type 47 (62.2) 6 (40.0) P value 0.154 * Statistically significant (P < 0.05). TABLE 3: Univariate and multivariate analyses of relapse-free survival rates using the Cox proportional hazards model in all patients. Univariate analysis Hazard ratio 95% CI P value Age (>60 versus [less than or 1.623 0.982-2.683 0.059 equal to] 60 years) Sex (female versus male) 0.804 0.45-1.439 0.463 Advanced T stage (pT4 versus 3.088 1.557-6.045 0.001 pT2-3) Advanced N stage (pN2-3 versus 3.688 2.157-6.304 <0.001 pN0-1) Lauren classification (diffuse 1.505 0.905-2.501 0.115 versus nondiffuse) Lymphatic invasion (yes versus 2.956 1.272-6.869 0.012 no) Venous invasion (yes versus 1.821 0.782-4.238 0.165 no) Tumor grade (moderate-poor 4.199 1.026-17.184 0.046 versus well) Adjuvant chemotherapy (yes 0.839 0.51-1.381 0.490 versus no) LNR (>median versus [less than 4.551 2.567-8.069 <0.001 or equal to] median) Tumoral Cav-1 expression, 0.95 0.452-1.996 0.892 primary tumor (high versus low) Stromal Cav-1 expression, 1.529 0.881-2.652 0.131 primary tumor (high versus low) Tumoral Cav-1 expression, 2.874 1.491-5.540 0.002 lymph node (high versus low) Multivariate analysis Hazard ratio 95% CI P value Age (>60 versus [less than or 2.158 1.207-3.862 0.009 equal to] 60 years) Sex (female versus male) Advanced T stage (pT4 versus 2.464 0.995-6.102 0.051 pT2-3) Advanced N stage (pN2-3 versus 1.491 0.208-2.156 0.502 pN0-1) Lauren classification (diffuse 1.917 1.032-3.562 0.039 versus nondiffuse) Lymphatic invasion (yes versus 1.479 0.543-0.032 0.444 no) Venous invasion (yes versus 0.483 0.778-5.498 0.145 no) Tumor grade (moderate-poor 1.754 0.112-2.911 0.498 versus well) Adjuvant chemotherapy (yes versus no) LNR (>median versus [less than 2.282 0.926-5.626 0.072 or equal to] median) Tumoral Cav-1 expression, 1.275 0.485-3.350 0.622 primary tumor (high versus low) Stromal Cav-1 expression, 0.956 0.516-2.116 0.902 primary tumor (high versus low) Tumoral Cav-1 expression, 3.934 1.882-8.224 <0.001 lymph node (high versus low) LNR: lymph node ratio. TABLE 4: Univariate and multivariate analyses by cancer-specific survival rates using the Cox proportional hazards model in all patients. Univariate analysis Hazard ratio 95% CI P value Age (>60 versus [less than or 1.143 0.623-2.095 0.666 eqaul to] 60) Sex (female versus male) 0.9 0.452-1.792 0.765 Advanced T stage (pT4 versus 3.452 1.453-8.202 0.005 pT2-3) Advanced N stage (pN2-3 versus 4.344 2.214-8.522 <0.001 pN0-1) Lauren classification (diffuse 1.532 0.827-2.838 0.175 versus nondiffuse) Lymphatic invasion (yes versus 12.903 1.774-93.854 0.012 no) Venous invasion 2.744 1.149-6.553 0.023 (yes versus no) Tumor grade (moderate-poor 2.866 0.692-11.86 0.146 versus well) Adjuvant chemotherapy (yes 0.794 0.433-1.454 0.454 versus no) LNR (>median versus [less than 6.476 2.987-14.042 <0.001 or eqaul to] median) Tumoral Cav-1 expression, 0.496 0.153-1.605 0.242 primary tumor (high versus low) Stromal Cav-1 expression, 1.48 0.756-2.897 0.253 primary tumor (high versus low) Tumoral Cav-1 expression, 3.064 1.429-6.569 0.004 lymph node (high versus low) Multivariate analysis Hazard ratio 95% CI P value Age (>60 versus [less than or eqaul to] 60) Sex (female versus male) Advanced T stage (pT4 versus 3.366 1.010-11.214 0.048 pT2-3) Advanced N stage (pN2-3 versus 1.919 0.147-1.838 0.310 pN0-1) Lauren classification (diffuse 0.506 0.928-4.204 0.077 versus nondiffuse) Lymphatic invasion (yes versus 5.759 0.718-46.228 0.099 no) Venous invasion 0.380 0.990-6.990 0.052 (yes versus no) Tumor grade (moderate-poor 2.983 0.057-1.970 0.226 versus well) Adjuvant chemotherapy (yes versus no) LNR (>median versus [less than 0.2662 1.122-12.579 0.031 or eqaul to] median) Tumoral Cav-1 expression, 0.3945 0.084-1.849 0.237 primary tumor (high versus low) Stromal Cav-1 expression, primary tumor (high versus low) Tumoral Cav-1 expression, 2.681 1.612-8.623 0.002 lymph node (high versus low) LNR: lymph node ratio. TABLE 5: Univariate and multivariate analyses of relapse-free survival rates using the Cox proportional hazards model in patients with metastatic lymph nodes. Characteristics Univariate analysis Hazard ratio 95% CI P value Age (>60 versus [less than or 2.254 1.295-3.922 0.004 equal to] 60 years) Sex (female versus male) 1.331 0.722-2.453 0.360 Advanced T stage (pT4 versus 2.414 1.030-5.655 0.042 pT2-3) Advanced N stage (pN2-3 versus 2.064 1.059-4.022 0.033 pN1) Lauren classification (diffuse 1.411 0.809-2.462 0.225 versus nondiffuse) Lymphatic invasion (yes versus 1.103 0.344-3.542 0.869 no) Venous invasion (yes versus 1.512 0.644-3.552 0.343 no) Tumor grade (moderate-poor 1.429 0.348-5.876 0.620 versus well) Adjuvant chemotherapy (yes 0.450 0.262-0.775 0.004 versus no) LNR (>median versus [less than 2.910 1.309-6.468 0.009 or equal to] median) Tumoral Cav-1 expression, 1.090 0.466-2.551 0.842 primary tumor (high versus low) Stromal Cav-1 expression, 1.354 0.751-2.441 0.313 primary tumor (high versus low) Tumoral Cav-1 expression, 2.79 1.447-5.379 0.002 lymph node (high versus low) Characteristics Multivariate analysis Hazard ratio 95% CI P value Age (>60 versus [less than or 2.252 1.251-4.052 0.006 equal to] 60 years) Sex (female versus male) Advanced T stage (pT4 versus 2.750 1.110-6.810 0.028 pT2-3) Advanced N stage (pN2-3 versus 1.767 0.535-5.834 0.350 pN1) Lauren classification (diffuse versus nondiffuse) Lymphatic invasion (yes versus no) Venous invasion (yes versus no) Tumor grade (moderate-poor versus well) Adjuvant chemotherapy (yes 0.517 0.266-1.002 0.050 versus no) LNR (>median versus [less than 2.154 0.873-5.315 0.095 or equal to] median) Tumoral Cav-1 expression, 0.793 0.264-2.383 0.680 primary tumor (high versus low) Stromal Cav-1 expression, 1.122 0.575-2.186 0.735 primary tumor (high versus low) Tumoral Cav-1 expression, 3.136 1.444-6.810 0.003 lymph node (high versus low) LNR: lymph node ratio. TABLE 6: Univariate and multivariate analyses of cancer-specific survival rates using the Cox proportional hazards model in patients with metastatic lymph nodes. Characteristics Univariate analysis Hazard ratio 95% CI P value Age (>60 versus [less than or 1.723 0.901-3.300 0.100 equal to] 60 years) Sex (female versus male) 1.524 0.751-3.091 0.243 Advanced T stage (pT4 versus 3.318 1.018-10.816 0.047 pT2-3) Advanced N stage (pN2-3 versus 2.379 1.041-5.436 0.040 pN1) Lauren classification (diffuse 1.291 0.669-2.491 0.446 versus nondiffuse) Lymphatic invasion (yes versus 2.352 0.322-17.163 0.399 no) Venous invasion (yes versus 2.233 0.923-5.399 0.075 no) Tumor grade (moderate-poor 1.083 0.260-4.505 0.913 versus well) Adjuvant chemotherapy (yes 0.487 0.255-0.932 0.030 versus no) LNR (>median versus [less than 4.911 1.505-16.03 0.008 or equal to] median) Tumoral Cav-1 expression, 0.509 0.122-2.116 0.353 primary tumor (high versus low) Stromal Cav-1 expression, 1.324 0.652-2.687 0.437 primary tumor (high versus low) Tumoral Cav-1 expression, 2.985 1.392-6.399 0.005 lymph node (high versus low) Characteristics Multivariate analysis Hazard ratio 95% CI P value Age (>60 versus [less than or 2.248 1.023-4.937 0.437 equal to] 60 years) Sex (female versus male) Advanced T stage (pT4 versus 3.905 1.173-12.992 0.026 pT2-3) Advanced N stage (pN2-3 versus 2.100 0.635-8.025 0.252 pN1) Lauren classification (diffuse versus nondiffuse) Lymphatic invasion (yes versus no) Venous invasion (yes versus 1.848 0.709-4.818 0.208 no) Tumor grade (moderate-poor versus well) Adjuvant chemotherapy (yes 3.905 1.173-12.992 0.032 versus no) LNR (>median versus [less than 3.451 1.026-11.606 0.045 or equal to] median) Tumoral Cav-1 expression, 0.328 0.071-1.512 0.152 primary tumor (high versus low) Stromal Cav-1 expression, primary tumor (high versus low) Tumoral Cav-1 expression, 2.509 1.078-5.837 0.032 lymph node (high versus low) LNR: lymph node ratio.
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|Title Annotation:||Research Article|
|Author:||Sun, Der Sheng; Hong, Soon Auck; Won, Hye Sung; Yoo, Su Hyun; Lee, Han Hong; Kim, Okran; Ko, Yoon Ho|
|Publication:||Gastroenterology Research and Practice|
|Date:||Jan 1, 2017|
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