Impact of metformin on survival outcome of esophageal squamous cell carcinomas patients undergoing surgical resection: a multicenter retrospective study.

BACKGROUND: Diabetes mellitus is a recognized risk factor for esophageal squamous cell carcinomas (ESCC), and metformin is a recognized protective factor for some gastrointestinal tumors. But knowledge is limited regarding the effect of metformin on survival outcome of ESCC patients with type 2 diabetes mellitus (T2DM). We assessed the impact of post-diagnosis metformin use on overall survival (OS) and disease-free survival (DFS) in ESCC with T2DM undergoing surgical resection. METHODS: A retrospective analysis was performed on 3,523 patients with ESCC who met the study conditions after surgical resection. Log-rank and Cox regression models were used to evaluate the relationship between metformin and T2DM and ESCC survival rate, and adjusted according to age, gender, BMI, smoking, drinking and staging, et al. RESULTS: Among included ESCC patients, 619 were associated with type 2 diabetes, while the remaining 2,904 were not associated with type 2 diabetes. The 5-year OS (28.43%) of patients with T2DM was significantly lower than that of patients without T2DM (32.75%), P=0.037. DFS in 5 years were 27.30% (with T2DM) and 31.75% (without T2DM) (P=0.030), respectively. Compared with patients without T2DM, patients with T2DM presented worse OS [adjusted risk ratio (HRadj) =1.19] and DFS (HRadj =1.17; P<0.001). Among the 619 patients with type 2 diabetes, 485 were treated with metformin and 134 were not treated with metformin. Patients treated with metformin had significantly improved OS [adjusted risk ratio (HRadj) =0.89; P=0.031) and DFS (HRadj =0.90; P=0.013). CONCLUSIONS: T2DM was again associated with poorer survival in ESCC patients, and metformin may improve the prognosis of these patients.

Preoperative Administration of Olive Oil Reduces Chylothorax After Minimally Invasive Esophagectomy.

BACKGROUND: Chylothorax after esophagectomy is uncommon but potentially fatal. We performed a retrospective study to assess the effect of olive oil administered orally before surgery on reducing chylothorax in patients who underwent minimal invasive esophagectomy. METHODS: Between May 2013 and December 2016, patients with esophageal squamous cell cancer who underwent minimal invasive esophagectomy were screened. Patients in the investigational group were preoperatively administered olive oil orally 8 hours before surgery, and patients in the control arm received no olive oil. We used a propensity score matching model to derive 1:1 cohorts. Statistical analysis was performed by using the t test or χ2 or Fisher's exact test. RESULTS: The propensity score matching model finally selected 384 of 425 patients, with 192 patients in each group. The patient characteristics were balanced. Oral olive oil was well tolerated. The thoracic duct identification rate was higher in the investigational group (100% versus 45.31%, χ2 = 141.78, p < 0.01). The investigational group was associated with a reduced incidence of ligation (7.81% versus 18.22%, χ2 = 8.03, p = 0.003). The incidence of chylothorax was significantly reduced in the investigational group compared with that of the control group (0% versus 3.12%, χ2 = 4.23, p = 0.03). CONCLUSIONS: Preoperative administration of olive oil is a simple and safe method to minimize chylothorax complicating minimal invasive esophagectomy.

Inhibition of pancreatic stellate cell activity by adipose-derived stem cells.

BACKGROUND: Pancreatic stellate cells (PSCs) play a critical role in the development of pancreatic fibrosis. In this study we used a novel method to isolate and culture rat PSCs and then investigated the inhibitory effects of adipose-derived stem cells (ADSCs) on activation and proliferation of PSCs. METHODS: Pancreatic tissue was obtained from Sprague-Dawley rats for PSCs isolation. Transwell cell cultures were adopted for co-culture of ADSCs and PSCs. PSCs proliferation and apoptosis were determined using CCK-8 and flow cytometry, respectively. alpha-SMA expressions were analyzed using Western blotting. The levels of cytokines [nerve growth factor (NGF), interleukin-10 (IL-10) and transforming growth factor-beta1 (TGF-beta1)] in conditioned medium were detected by ELISA. Gene expression (MMP-2, MMP-9 and TIMP-1) was analyzed using qRT-PCR. RESULTS: This method produced 17.6+/-6.5X10(3) cells per gram of the body weight with a purity of 90%-95% and a viability of 92%-97%. Co-culture of PSCs with ADSCs significantly inhibited PSCs proliferation and induced PSCs apoptosis. Moreover, alpha-SMA expression was significantly reduced in PSCs+ADSCs compared with that in PSC-only cultures, while expression of fibrinolytic proteins (e.g., MMP-2 and MMP-9) was up-regulated and anti-fibrinolytic protein (TIMP-1) was down-regulated. In addition, NGF expression was up-regulated, but IL-10 and TGF-beta1 expressions were down-regulated in the co-culture conditioned medium compared with those in the PSC-only culture medium. CONCLUSIONS: This study provided an easy and reliable technique to isolate PSCs. The data demonstrated the inhibitory effects of ADSCs on the activation and proliferation of PSCs in vitro.

A molecular prognostic model predicts esophageal squamous cell carcinoma prognosis.

BACKGROUND: Esophageal squamous cell carcinoma (ESCC) has the highest mortality rates in China. The 5-year survival rate of ESCC remains dismal despite improvements in treatments such as surgical resection and adjuvant chemoradiation, and current clinical staging approaches are limited in their ability to effectively stratify patients for treatment options. The aim of the present study, therefore, was to develop an immunohistochemistry-based prognostic model to improve clinical risk assessment for patients with ESCC. METHODS: We developed a molecular prognostic model based on the combined expression of axis of epidermal growth factor receptor (EGFR), phosphorylated Specificity protein 1 (p-Sp1), and Fascin proteins. The presence of this prognostic model and associated clinical outcomes were analyzed for 130 formalin-fixed, paraffin-embedded esophageal curative resection specimens (generation dataset) and validated using an independent cohort of 185 specimens (validation dataset). RESULTS: The expression of these three genes at the protein level was used to build a molecular prognostic model that was highly predictive of ESCC survival in both generation and validation datasets (P = 0.001). Regression analysis showed that this molecular prognostic model was strongly and independently predictive of overall survival (hazard ratio = 2.358 [95% CI, 1.391-3.996], P = 0.001 in generation dataset; hazard ratio = 1.990 [95% CI, 1.256-3.154], P = 0.003 in validation dataset). Furthermore, the predictive ability of these 3 biomarkers in combination was more robust than that of each individual biomarker. CONCLUSIONS: This technically simple immunohistochemistry-based molecular model accurately predicts ESCC patient survival and thus could serve as a complement to current clinical risk stratification approaches.

The prognostic implications of microvascular density and lymphatic vessel density in esophageal squamous cell carcinoma: Comparative analysis between the traditional whole sections and the tissue microarray.

Focal distribution of microvascular and lymphatic vessels is a critical issue in cancer, and is measured by tissue microarray (TMA) construction from paraffin-embedded surgically obtained tissues, a process that may not accurately reflect true focal distribution. The aim of this study was to assess the concordance of microvascular density (MVD) and lymphatic vessel density (LVD) in TMAs with corresponding whole sections, and to correlate the MVD or LVD with clinicopathological parameters in 124 cases of esophageal squamous cell carcinoma (ESCC). MVD, determined by CD105 immunohistochemistry of whole sections, was strongly associated with lymph node metastasis (p=0.000) and pTNM stage (p=0.001). Kaplan-Meier survival analysis showed that increasing CD105 microvessel count correlated with decreasing survival (p<0.001). The same result was acquired when MVD was calculated from tissue microarrays. Analysis of continuous data showed a highly significant correlation between whole sections and TMA data (Pearson r=0.522, p<0.001). Increasing LVD, as determined by D2-40 immunohistochemistry of whole sections, correlated with decreasing survival, but this relationship was undetectable using TMAs. In conclusion, we demonstrate that for the selected endothelial markers, TMAs can provide a realistic and reliable estimate of the extent of MVD, but not LVD in ESCC samples.

[Anatomy of mesoesophagus in esophagectomy with minimally invasive three-fields lymphadenectomy].

OBJECTIVE: To explore the anatomic features of mesoesophagus in combined thoracoscopic and laparoscopic esophagectomy with three-fields lymphadenectomy. METHODS: Clinical data of 67 patients undergoing thoracoscopic and laparoscopic esophagectomy with three-fields lymphadenectomy from July 2011 to September 2012 were analyzed retrospectively. All the patients underwent three-fields lymphadenectomy. Proper surgical planes were selected according to anatomy of mesoesophagus. Thoracoscopic surgical space was bounded on azygotic vein and divided into upper and low esophageal triangle. Pancreas was the key anatomical mark for laparoscopic gastric dissection, and peripancreatic space was the natural laparoscopic surgical plane. Prevertebral fascia was bottom surface of neck dissection and carotid sheath was the boundary of two sides. RESULTS: The median operative time was 251.6 min (range, 220 to 320 min). The median operative blood loss was 105.6 ml (range, 40 to 320 ml). The median number of lymph nodes dissected was 29.1 (range, 13 to 46, totally 1949). There was no perioperative death. Sixty-six patients were followed up with a mean follow-up time of 8.2 months (range, 2 to 14 months). Postoperative complications included reflux esophagitis in 10 and anastomotic stenosis in 3 cases. CONCLUSION: It is safe and more radical for minimally invasive esophagectomy that overall concept of minimally invasive anatomy of mesoesophagus is applied to identify the anatomic plane and landmark during operation.

[Effects of glycogen synthase kinase 3ß overexpression in rat and glycogen synthase kinase 3ß inhibitor SB-216763 on proliferation of hepatic oval cells].

OBJECTIVE: To research the effects of glycogen synthase kinase (GSK3ß) overexpression and GSK3ß inhibitor SB-216763 on the proliferation of hepatic oval cells in rats and its regulatory mechanisms by Wnt signaling pathway. METHODS: The hepatic oval cells WBF-344 were divided into the blank control group, GSK3ß over-expression group, DMSO control group and GSK3ß inhibitor groups, while the inhibitor groups set up three concentration gradients, that was 1, 5, 10 µmol/L. Using the GSK3ß over-expression lentivirus, which had been identified correctly, and SB-216763 dealt with the cells WBF-344. The cells morphology of each group was observed under the phase contrast inverted microscope, and the expression of fluorescence in the lentivirus-transfected group was observed under the fluorescent microscope. The proliferation of each group cells was tested by CCK8 kits. The cells' apoptosis was detected by AnnexinV-FITC/PI kits. The expression of GSK3ß, ß-catenin and cyclin D1 were detected by Western blot. RESULTS: The cells of GSK3ß over-expression group were fewer and obvious aging. However, in each inhibitor added group, the cells' division and proliferation was vigorous, and the condition was good. Moreover, the cells' proliferation was getting stronger with the concentration of SB-216763 increasing. A large number of green fluorescence was expressed in the lentivirus-transfected cells. The cells' proliferation in GSK3ß over-expression group restrained (t = 7.178, P < 0.01, as compared with control), while the cells' proliferation was vigorous in inhibitor groups (F = 45.030, P < 0.01, as compared with control). Flow Cytometry showed that the cells apoptosis was significant in GSK3ß over-expression group. Western blot showed that the expression of GSK3ß was increased, while the expression of ß-catenin and cyclin D1 was decreased in the over-expression group. The expression of GSK3ß had no significant difference among the control group and inhibitor groups. However, the expression of ß-catenin and cyclin D1 was significantly increased with the concentration of SB-216763 increasing. CONCLUSIONS: The overexpression of GSK3ß can inhibit the Wnt signaling pathway, thus restrain the cells' proliferation and promotes apoptosis. SB-216763 can activate the Wnt pathway, thus promotes cells' proliferation.

Prognostic significance of perigastric lymph nodes metastases on survival in patients with thoracic esophageal cancer.

Several publications have showed that the number of metastatic lymph node (LN) should be taken into consideration in nodal category of esophageal cancer, but seldom considered extent of involved regional LNs. The aim of this study is to evaluate the significance of the extent of regional LN metastasis on survival in patients with esophageal cancer. A total of 245 thoracic esophageal cancer patients underwent transthoracic esophagectomy with standard lymphadenectomy between January 2000 and December 2006 were included in the study. Data including demographic factors, pathologic findings, LN parameters and survival outcomes were collected. The survival experience was depicted using Kaplan-Meier method. A multivariate Cox proportional hazard model was used to screen the significant prognostic factors. The univariate analysis to further explore the significant prognostic factor was done by log-rank test. After a median follow-up of 53.2 months, the 5-year survival rate was 46.3% for the entire cohort. Cox model regression indicated that the LN status and perigastric nodal status, aside from residual tumor status, histological tumor type and depth of invasion, were the independent prognostic factors. Patients without LN metastasis had better 5-year survival than those with positive nodes (64.2% vs. 18.9%, X2=35.875, P<0.001). However, For those patients with nodal involvement, there was no difference in 5-year survival between patients with involved nodes<3 and >or=3 (27.8% vs. 0%, X2=0.925, P=0.336). When considering the location of LN metastasis, patients could be further stratified according to whether the perigastric nodes were involved or not (37.5% vs. 10.0%, X2=4.295, P=0.038). In conclusion, involved LN number had no prognostic implication in nodal involved patients based on our data. Whereas, perigastric nodal involvement should be used to refine the N category (N0, no nodal metastasis, N1, non-perigastric node metastasis, N2, perigastric node metastasis) for the future esophageal cancer staging criteria.