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Background & aims Intrahepatic cholangiocarcinoma (ICC) is aggressive and has high rates of relapse, conferring poor long-term survival after curative resection. Little is known about the genomic evolution that occurs during ICC relapse. Approach & results We conducted whole-exome sequencing (WES) of 30 paired primary and relapsed tumors from 10 patients with ICC who received curative resection. We sought to identify frequently altered genes, infer tumor subclonal architectures, and track genomic evolution from primary to relapsed tumors. We examined functional effects and the mechanism of action of SLIT2, a gene specifically mutated in relapsed tumors, on tumor growth and metastasis and the tumor microenvironment. Our results indicated that relapsed ICCs were genetically derived from intrahepatic dissemination of primary tumors. But, they acquired additional mutations while maintaining most drivers, such as TP53 and IDH1. Multiregion sequencing suggested polyclonal seeding of ICC dissemination. Four of 10 relapsed ICCs acquired SLIT2 mutations that were not present in the corresponding primary tumors. Validation in an expanded sample revealed SLIT2 mutations in 2.3% (1/44) of primary ICCs and 29.5% (13/44) of relapsed ICCs. Biofunctional investigations revealed that inactivating mutation of SLIT2 resulted in activation of PI3K-Akt signaling in ICC cells, directly enhanced neutrophil chemotaxis, mediated tumor-associated neutrophil infiltration, and contributed to ICC growth and metastasis. Conclusions We characterized genomic evolution during ICC relapse and identified SLIT2 as a driver of tumor dissemination and tumor-associated neutrophil infiltration.

Background & Aims Early recurrence of hepatocellular carcinoma (HCC) after curative resection is common. However, the association between genetic mechanisms and early HCC recurrence, especially in Chinese patients, remains largely unknown. Methods We performed whole-genome sequencing (49 cases), whole-exome sequencing (18 cases), and deep targeted sequencing (115 cases) on 182 primary HCC samples. Focusing on WNK2, we used Sanger sequencing and qPCR to evaluate all the coding exons and copy numbers of that gene in an additional 554 HCC samples. We also explored the functional effect and mechanism of WNK2 on tumor growth and metastasis. Results We identified 5 genes (WNK2, RUNX1T1, CTNNB1, TSC1, and TP53) harboring somatic mutations that correlated with early tumor recurrence after curative resection in 182 primary HCC samples. Focusing on WNK2, the overall somatic mutation and copy number loss occurred in 5.3% (39/736) and 27.2% (200/736), respectively, of the total 736 HCC samples. Both types of variation were associated with lower WNK2 protein levels, higher rates of early tumor recurrence, and shorter overall survival. Biofunctional investigations revealed a tumor-suppressor role of WNK2: its inactivation led to ERK1/2 signaling activation in HCC cells, tumor-associated macrophage infiltration, and tumor growth and metastasis. Conclusions Our results delineate genomic events that characterize Chinese HCCs and identify WNK2 as a driver of early HCC recurrence after curative resection. Lay summary We applied next-generation sequencing and conducted an in-depth genomic analysis of hepatocellular carcinomas from a Chinese patient cohort. The results delineate the genomic events that characterize hepatocellular carcinomas in Chinese patients and identify WNK2 as a driver associated with early tumor recurrence after curative resection.

Osteosarcoma is the most common primary bone malignancy, and the lung is the most frequent site of metastasis. The limited understanding of the tumoral heterogeneity and evolutionary process of genomic alterations in pulmonary metastatic osteosarcoma impedes development of novel therapeutic strategies. Here we systematically illustrate the genomic disparities between primary tumors and corresponding pulmonary metastatic tumors by multiregional whole-exome and whole-genome sequencing in 86 tumor regions from 10 patients with osteosarcoma. Metastatic tumors exhibited a significantly higher mutational burden and genomic instability compared with primary tumors, possibly due to accumulation of mutations caused by a greater number of alterations in DNA damage response genes in metastatic tumors. Integrated analysis of the architecture and relationships of subclones revealed a dynamic mutational process and diverse dissemination patterns of osteosarcoma during pulmonary metastasis (6/10 with linear and 4/10 with parallel evolutionary patterns). All patients demonstrated more significant intertumoral rather than intratumoral heterogeneity between primary tumors and metastatic tumors. Mutated genes were enriched in the PI3K–Akt pathway at both the early and late stages of tumor evolution and in the MAPK pathway at the metastatic stage. Conversely, metastatic tumors showed improved immunogenicity, including higher neoantigen load, elevated PD-L1 expression, and tumor-infiltrating lymphocytes than the corresponding primary tumors. Our study is the first to report the dynamic evolutionary process and temporospatial tumor heterogeneity of pulmonary metastatic osteosarcoma, providing new insights for diagnosis and potential therapeutic strategies for pulmonary metastasis. Significance: High-throughput sequencing of primary and metastatic osteosarcoma provides new insights into the diagnosis of and potential clinical therapeutic strategies for pulmonary metastasis.

Currently CNG has been widely used as an automotive fuel, and the security problems about CNG storage well are prominent which poses a serious threat to life and property.This indicates that the safety of the underground gas storage well stored CNG is of great importance. The purpose of this paper is to analyze the section of gas storage well that is the joint of casing and coupling based on the finite element method,as this section is the most dangerous.Using ANSYS software,the stress field of this section will be acquired.An example of a finite element model will be used to demonstrate the main section related to gas storage well failure is the root of the first engaged tooth of a joint between coupling and casing.

Minimally invasive robotic surgery has been investigated in various surgical application due to high accuracy, fine manipulation capability, tele-operation. Haptic feedback plays a significant role in MIS. In this paper, a dynamics model of a haptic robot is established, and PID algorithm is proposed. To prove the proposed method, an experimental system has been developed. Simulations and experiments show proposed methods is an effective method to master-slave MIRS.

To evaluate the safety and feasibility of laparoscopic abdominoperineal resection compared with the open procedure in multimodality management of rectal cancer.A total of 106 rectal cancer patients who underwent open abdominoperineal resection (OAPR) were matched with 106 patients who underwent laparoscopic abdominoperineal resection (LAPR) in a 1 to 1 fashion, between 2009 and 2013 at Fudan University Shanghai Cancer Center. Propensity score matching was carried out based on age, gender, pathological staging of the disease and administration of neoadjuvant chemoradiation. Data regarding preoperative staging, surgical technique, pathological results, postoperative recovery and complications were reviewed and compared between the LAPR and OAPR groups. Perineal closure around the stoma and pelvic floor reconstruction were performed only in OAPR, not in LAPR. Therefore, abdominoperineal resection procedure-specific surgical complications including parastomal hernia and perineal wound complications were compared between the open and laparoscopic procedure. Regular surveillance of the two cohorts was carried out to gather prognostic data. Disease-free survival was analyzed using Kaplan-Meier estimate and log-rank test. Subgroup analysis was performed in patients with locally advanced disease treated with preoperative chemoradiation followed by surgical resection.No significant difference was found between the LAPR group and the OAPR group in terms of clinicopathological features. The operation time (180.8 ± 47.8 min vs 172.1 ± 49.2 min, P = 0.190), operative blood loss (93.9 ± 60.0 mL vs 88.4 ± 55.2 mL, P = 0.494), total number of retrieved lymph nodes (12.9 ± 6.9 vs 12.9 ± 5.4, P = 0.974), surgical complications (12.3% vs 15.1%, P = 0.549) and pathological characteristics were comparable between the LAPR and OAPR group, respectively. Compared with OAPR patients, LAPR patients showed significantly shorter postoperative analgesia (2.4 ± 0.7 d vs 2.7 ± 0.6 d, P0.001), earlier first flatus (57.3 ± 7.9 h vs 63.5 ± 9.2 h, P0.001), shorter urinary drainage time (6.5 ± 3.4 d vs 7.8 ± 1.3 d, P0.001), and shorter postoperative admission (11.2 ± 4.7 d vs 12.6 ± 4.0 d, P = 0.014). With regard to APR-specific complications (perineal wound complications and parastomal hernia), there were no significant differences between the two groups. Similar results were found in the 26 pairs of patients administered neoadjuvant chemoradiation in subgroup analysis. During the follow-up period, no port site recurrences were observed.Laparoscopic abdominoperineal resection for multidisciplinary management of rectal cancer is safe, and is associated with earlier recovery and shorter admission time in combination with neoadjuvant chemoradiation.

We report the fabrication of simply structured and high performance organic complementary inverters based on an ambipolar organic semiconductor, 8,9,10,11-tetrachloro-6,13-bis-(triisopropylsilylethynyl)-1-azapentacene (4Cl-Azapen). Individual transistors using symmetric Au electrodes showed high and balanced performance, with good hole (up to 0.23 cm2V−1s−1) and electron (up to 0.21 cm2V−1s−1) mobilities. Integrated complementary inverters showed sharp inversions with high gains (>180) and negligible hysteresis. The inverters using low-cost electrodes, Ag and Cu, also exhibited high gains and high noise margins (>75% of the ideal value).