Objective:To investigate the inhibitory effect of Dickkopf-1 (Dkk1) on vasculogenic mimicry (VM) formation and the relevant mechanism. Methods:CD34-PAS dual staining and immunohistochemical staining were used to detect and analyze the re-lationship between VM existence and Dkk1 expression in 217 human colon cancer tissue samples;three dimensional (3D) culture was used to detect the influence of Dkk1 on tube structure formation and on VE-cadherin expression;a subcutaneous mouse xenograft mod-el was made to further validate the inhibitory role of Dkk1 on VM formation in vivo. Results:VM-positive samples indicated a lower expression of Dkk1(P<0.05);colon cancer cells with Dkk1 overexpression exhibited a decreased ability to form tube-like structure and a decreased expression of VE-cadherin;Dkk1 inhibited the VM-formation abilities of human colorectal carcinoma cell line xenograft tu-mor tissue. Conclusion:Dkk1 inhibits the VM formation of colon cancer.

Objective:This study aims to investigate the potential of colon cancer cells to differentiate into vascular endothelial cells in endothelial-induced specific environment. Methods:Three colon cancer cells with different differentiated level HCT116 (poor-ly differentiated), SW480 (moderately differentiated), HT29 (well differentiated) were cultured in the conditioned medium containing the endothelial-inducing factors for 15 days respectively. The expression of vascular endothelial indicators Platelet endothelial cell adhe-sion molecule-1、Endothelial cell adhesion molecule CD34 was detected via western blot. Immunofluorescence staining was performed to examine CD31 and CD34 expression level in HCT116 after cultured in endothelial-inducing medium and ordinary medium for 15 days respectively, and the three-dimensional (3D) culture was used to detect the abililty of in vitro tube-like structure formation. Re-sults:Western blot showed that CD31 and CD34 expression level were negatively correlated with degree of differentiation in colon can-cer cells. CD31 and CD34 expression in endothelial-inducing medium HCT116 cells (poorly differentiated) were higher then in the nor-mal medium, while the CD31 and CD34 expression in SW480 cells (moderately differentiated) and HT29 cells (well differentiated) in the two cultural mediums were not notably changed. Immunofluorescence staining illustrated that CD31 and CD34 expression in HCT116 cells cultured in endothelial-inducing medium increased compared with those cultured in ordinary medium. In vitro three-di-mensional culture demonstrated that ability of tube-like structure formation was notably enhanced after endothelial-inducing cultured. Conclusion:Endothelial-inducing medium could promote colon cancer cells with strong stemness differentiate toward vascular endo-thelial cells.

Objective:To explore the clinicopathological characteristics and prognostic factors of neuroendocrine neoplasms(NENs)at different sites in the digestive system.Methods:The clinicopathological parameters and follow-up data were collected from 284 pa-tients with NENs in the digestive system in Tianjin Medical University Cancer Institute and Hospital from March 2011 to December 2015.The incidence and clinicopathological features were compared between the cases of NENs at different sites and survival analysis was performed.Results:In this study,NENs were detected mostly frequently in the pancreas,followed by the colorectum and stom-ach.In the pancreas,neuroendocrine tumor(NET)G1(51.8%)and G2(35.8%)accounted for a large proportion of NENs.World Health Organization(WHO)grades were related to lymph node metastasis,adjacent organ invasion,and nerve invasion(P<0.05 for all)but were not associated with the overall survival time of the patients.The patients with pancreatic NENs with distant metastasis had poor overall survival(P<0.05).Regarding colorectal NENs,most patients had NET G1(82.5%),and the majority of patients were cured with endoscopic or transanal resection.Patients with NENs,lymph node metastasis,and distant metastasis had poor overall survival(P<0.05 for all).The ratio of male-to-female patients,proportion of patients aged older than 40 years,prevalence of neuroendocrine carci-nomas(NECs)and mixed adenoneuroendocrine carcinomas(MANECs),presence of lymph node and distant metastasis,and presence of advanced stage tumors were greater in patients with gastric NENs than in patients with pancreatic and colorectal NENs(P<0.05 for all).WHO grades and lymph node metastasis were associated with the overall survival time of patients with gastric NENs(P<0.05 for both).Conclusions:NENs in the digestive system are a group of heterogeneous tumors with different clinicopathological features at different sites.The distribution and clinicopathological features of Chinese patients with NENs in the digestive system are different from those of European and American patients.More multicenter studies with large sample sizes are still needed to understand the bi-ological behaviors and prognostic factors of NENs at different sites in the digestive system.

Objective: To detect the expression of SVEP1, PKHD1 and P53 in primary liver cancer tissues by immunohistochemistry for predicting the recurrence of liver cancer. Methods: The clinical data of 103 patients with primary liver cancer who underwent surgical resection at Tianjin Medical University Cancer Institute and Hospital were gathered from January 2013 to January 2014 and analyzed retrospectively. Expression values of three different proteins were used to develop separate immunohistochemical scores for the prog-nosis of recurrence in patients. The patients were classified into either a high-risk or a low-risk group based on their immunohisto-chemical scores through ROC curve analysis. The difference in recurrence ratio between the two groups was then compared using the common research index of disease-free survival (DFS). Results: The median age of the total patients was 55 years (range 21-88 years), the median AFP level was 70.6 (range 1.03-718840.0) μg/L, the median CA19-9 level was 22.89 (range 0.6-1000.0) kU/L, and the medi-an tumor size was 4.5 (1.0-27.0) cm. The expression levels of SVEP1, PKHD1, and P53 in primary liver tumors were detected by immu-nohistochemistry and assigned separate immunohistochemical scores. The areas under the ROC curves of the immunohistochemical scores of SVEP1, PKHD1, and P53 were 0.861, 0.829, and 0.716, respectively. The critical values of SVEP1, PKHD1, and P53 were 4, 4, and 1 point, respectively (P<0.001). The three-year DFS rates among the SVEP1 high-risk (expression≤4 points) and low-risk groups (expression>4 points) were 4.1% and 51.7%, respectively. Similarly, the three-year survival rates among the PKHD1 high-risk (expres-sion≤4 points) and low-risk groups (expression>4 points) were 5.3% and 51.9%, respectively. The three-year DFS rates among the P53 high-risk (expression>1 point) and the low-risk group (expression≤1 point) were 6.3% and 27.3%, respectively. The survival differenc-es between all the pairs were statistically significant (P<0.001,<0.001, and 0.003 respectively). When PKHD1 was used in combination with SVEP1, the ROC curve had an area of 0.897 (P<0.001) with a sensitivity of 76.5% and a specificity of 94.4%. Conclusions: The accu-racy of P53 data for predicting primary liver cancer recurrence is insufficient and therefore it is not recommended for use. SVEP1 and PKHD1 data achieve sufficient accuracy for predicting the recurrence of primary liver cancer. Since SVEP1 data impart a higher specifici-ty and PKHD1 data impart a higher sensitivity to the prognosis scores, the combined use of the two markers is better than being used individually.

Objective:To investigate the difference of clinicopathological characteristics between mixed medullary and papillary carcinoma of thyroid and medullary carcinoma coexistent with papillary carcinoma.Method:The clinicopathological data of 3 MMPTC cases and 9 MTC-PTC cases treated at Tianjin Medical University Cancer Institute & Hospital during the past ten years were retrospectively analyzed. The differences in clinical characteristics, pathological characteristics, immunohistochemistry results, treatment and prognosis of the two groups were compared.Results:In the MMPTC group, the median onset-age was 59 years old. 3 patients were all medullary carcinoma colliding with micropapillary carcinoma. The immunohistochemistry results showed that medullary carcinoma and papillary carcinoma showed their distinctive immunohistochemical characteristics. The lymph node metastasis rate was 66.7% (2/3). In MTC-PTC group, the median onset-age was 55; 8 out of 9 patients had an increased preoperative calcitonin level. Medullary carcinoma and papillary carcinoma showed their distinctive immunohistochemical characteristics. Four out of the 9 cases had lymph node metastasis.Conclusion:Compared with MTC-PTC, MMPTC is more common in middle-aged and elder patients, with higher lymph node metastasis rate. The pathogenesis of MTC-PTC is similar to papillary thyroid carcinoma, and the treatment should be individualized. The prognosis of these two groups of patients is fair.

Objective: To determine the expression of TAZ and its role in angiogenesis in gastric carcinoma. Methods: Immunohistochemical staining was performed to investigate the expression of TAZ and to determine whether a direct relationship exists between TAZ and β-catenin. Transfection with TAZ overexpression plasmid in MKN28 cells was conducted to induce exogenous expression of TAZ and a TAZ knockdown plasmid was transfected into MGC803 cells to reduce TAZ levels. The effects on endothelial cell formation, proliferation, and migration were determined by Matrigel three-dimensional culture, MTT proliferation assay and Transwell migration assay. In addition, the expression of TAZ and β-catenin in transfected gastric cancer cells was detected by Western blot. Results: Immunohistochemistry showed that TAZ protein was expressed in 64 of 150 gastric cancer sample tissues (43%), TAZ was localized in the nucleus, and its expression was associated with tumor grade, TNM stage, metastasis, and microvessel density (MVD) (P<0.05). In addition, the expression frequency of β-catenin in the TAZ positive group was 67.2%, which was significantly higher than that in the TAZ negative group, and the expression of TAZ was positively correlated with β-catenin. After transfection, TAZ overexpression increased the expression of β-catenin and enhanced HUVECs tube formation, proliferation, and migration. In the MGC803 cells transfected with the knockdown plasmid, β-catenin levels were decreased and HUVECs motility was inhibited. Conclusions: TAZ may promote angiogenesis in gastric cancer by promoting β-catenin expression.

Objective:To study the expression level of programmed death ligand 1 (PD-L1) in combined hepatocellular-cholangiocarcinoma (cHCC-CCA) and its correlation with the clinical characteristics and prognosis.Methods:The clinical data of 75 patients with cHCC-CCA undergoing surgery in Tianjin Medical University Cancer Institute and Hospital from January 2011 to December 2019, including 61 males and 14 females, with a median age of 55 years (36 to 77). Immunohistochemistry was conducted to determine the PD-L1 expression in tumor. The status of PD-L1 expression, clinicopathological data and prognosis of patients were analyzed.Results:In low-differentiated cHCC-CCA tissues, the proportion of PD-L1 expression (21.1%, 8/38) was higher than that in moderately to well-differentiated cHCC-CCA tissues (2.70%, 1/37, χ2=4.366, P=0.037). The median disease-free survival (DFS) and overall survival (OS)of PD-L1 positive patients were 12.3 and 15.1 months, respectively, lower than those of PD-L1 negative patients (14.4 and 23.3 months). The difference of DFS was statistically significant ( χ2=4.052, P=0.044). In multivariate analysis, major vascular invasion (DFS: HR=1.965, 95% CI: 1.119-3.450, P=0.019; OS: HR=1.781, 95% CI: 1.022-3.105, P=0.042) and lymph node metastasis (DFS: HR=2.451, 95% CI: 1.1033-5.814, P=0.042; OS: HR=2.652, 95% CI: 1.120-6.279, P=0.027) were identified as independent prognostic factors affecting DFS and OS. Conclusions:The proportion of PD-L1 positive is higher inthe low-differentiated cHCC-CCA tissue compared to that in moderately to well-differentiated cHCC-CCA. The major vascular invasion and lymph node metastasis are independent factors affecting the prognosis of patients with cHCC-CCA.