We investigated the value of subcarinal lymph node dissection in esophageal cancer surgery. Altogether, 240 patients with esophageal cancer admitted to our department between June 2012 and January 2016 were prospectively assigned to an experimental group (subcarinal lymph node dissection group, n = 120 cases) and a control group (uncleaned group, n = 120 cases). The number of subcarinal lymph nodes and the rate of subcarinal lymph node metastasis were determined, and the factors influencing subcarinal lymph node metastasis were analyzed using logistic regression in the experimental group. The operation time, postoperative complications, intraoperative blood loss, postoperative hospital stay, total postoperative hospital cost, and 5-year survival rate were compared between the 2 groups. In the experimental group, an average of 6.03 subcarinal lymph nodes were dissected, and the lymph node metastasis rate was 18.33%. The subcarinal lymph node metastasis rate in the experimental group was related to the size of the subcarinal lymph nodes, depth of tumor invasion, and tumor location. The 5-year survival rate was higher in the experimental group than in the control group (44.2% vs 30.0%, χ 2 = 6.407, P = .04). The subcarinal lymph node metastasis rate in patients with esophageal cancer is high. Patients with mid-thoracic esophageal cancers that infiltrate beyond the esophageal muscle layer with subcarinal lymph node size > 1.0 cm should undergo lymph node resection, despite increased operation time, incidence of postoperative pulmonary infection, hospitalization time, and total postoperative cost; lymph node resection may improve the 5-year survival rate.

Objective To explore functions of the histone H3 lysine 79 (K79) methyltransferase Dot1L in the development of pancreatic cancer and evaluate the possibility of targeting Dot1L to inhibit pancreatic cancer progression. Methods Patient samples were used to detect differences in Dot1L expression between tumor and adjacent tissues and to determine correlations between Dot1L expression in patients with different stages of pancreatic cancer. Lentiviral-mediated knockdown of Dot1L expression and flow cytometry were used to detect apoptosis in pancreatic cancer lacking Dot1L expression; chromatin immunoprecipitation and quantitative PCR were used to detect downstream target genes of Dot1L. Results We show that Dot1L is highly expressed in pancreatic cancer, and that its expression is related to pancreatic cancer stage. Knocking down Dot1L significantly promoted apoptosis in pancreatic cancer cells, while overexpressing Dot1L inhibited apoptosis. Mechanistically, Dot1L regulated apoptosis in pancreatic cancer cells by promoting NUPR1 expression. The enriched H3K79 trimethylation in the transcription initiation region of NUPR1 promoted its expression. Overexpressing NUPR1 inhibited the pancreatic cancer cell apoptosis caused by Dot1L knockdown. Conclusions Dot1L inhibits pancreatic cancer cell apoptosis by targeting NUPR1; thus, Dot1L is a promising target for pancreatic cancer treatment.

Background: This study aims to investigate the effectiveness of application of single-port thoracoscopy using the subxiphoid approach in anterior mediastinal tumor surgery. Methods: Between June 2014 and June 2016, a total of 108 patients (59 males, 49 females; mean age: 64.9±7.5 years; range, 45 to 79 years) with anterior mediastinal tumors were randomized into subxiphoid (experimental) or right chest (control) groups. Single-port thoracoscopy using the subxiphoid approach was performed in the subxiphoid group, while thoracoscopy using the right thoracic approach was performed in the control group. Preand postoperative pain stress indicators, Visual Analog Scale scores, quality of life scores, postoperative tumor recurrence, and five-year survival rates were compared between the groups. Results: There were no mortality or serious complications in either group. The mean Visual Analog Scale pain scores on postoperative Days 1 and 7 were 6.5±0.8 and 2.9±0.8 in the subxiphoid group, respectively, compared to 7.2±0.8 and 3.4±0.8 in the control group (p<0.05 for all), respectively. The mean quality of life scores on postoperative Days 1 and 7 were 81.5±5.0 and 79.3±7.7, respectively, in the subxiphoid group compared to 72.4±4.3 and 71.3±4.8 in the control group, respectively (p<0.05 for all). Postoperative pain and pain mediator indexes were lower in the subxiphoid group (p<0.05 for all). The postoperative tumor recurrence rates were 3.70% and 20.37% in the subxiphoid and control groups, respectively (p=0.008). The five-year survival rates were 85.2% and 63.0% in the subxiphoid and control groups, respectively (p=0.008). Conclusion: Single-port thoracoscopy using the subxiphoid approach is technically feasible, safe, and effective in performing surgery for anterior mediastinal tumors with an intact capsule and a tumor diameter of ≤5 cm.