Whole-genome sequencing reveals the evolutionary trajectory of HBV-related hepatocellular carcinoma early recurrence.

Patients with hepatocellular carcinoma (HCC) have poor long-term survival following curative resection because of the high rate of tumor early recurrence. Little is known about the trajectory of genomic evolution from primary to early-recurrent HCC. In this study, we performed whole-genome sequencing (WGS) on 40 pairs of primary and early-recurrent hepatitis B virus (HBV)-related HCC tumors from patients who received curative resection, and from four patients whose primary and recurrent tumor were extensively sampled. We identified two recurrence patterns: de novo recurrence (18/40), which developed genetically independently of the primary tumor and carried different HCC drivers, and ancestral recurrence (22/40), which was clonally related to the primary tumor and progressed more rapidly than de novo recurrence. We found that the recurrence location was predictive of the recurrence pattern: distant recurrence tended to display the de novo pattern, whereas local recurrence tended to display the ancestral pattern. We then uncovered the evolutionary trajectories based on the subclonal architecture, driver-gene mutations, and mutational processes observed in the primary and recurrent tumors. Multi-region WGS demonstrated spatiotemporal heterogeneity and polyclonal, monophyletic dissemination in HCC ancestral recurrence. In addition, we identified recurrence-specific mutations and copy-number gains in BCL9, leading to WNT/ß-catenin signaling activation and an immune-excluded tumor microenvironment, which suggests that BCL9 might serve as a new therapeutic target for recurrent HCC. Collectively, our results allow us to view with unprecedented clarity the genomic evolution during HBV-related HCC early recurrence, providing an important molecular foundation for enhanced understanding of HCC with implications for personalized therapy to improve patient survival.

Genomic evolution and the impact of SLIT2 mutation in relapsed intrahepatic cholangiocarcinoma.

BACKGROUND AND 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 AND RESULTS: We conducted whole-exome sequencing 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. However, 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.

Genomic sequencing identifies WNK2 as a driver in hepatocellular carcinoma and a risk factor for early recurrence.

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.

Multiregion Sequencing Reveals the Genetic Heterogeneity and Evolutionary History of Osteosarcoma and Matched Pulmonary Metastases.

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.

Laparoscopic vs open abdominoperineal resection in the multimodality management of low rectal cancers.

AIM: To evaluate the safety and feasibility of laparoscopic abdominoperineal resection compared with the open procedure in multimodality management of rectal cancer. METHODS: 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. RESULTS: 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, P < 0.001), earlier first flatus (57.3 ± 7.9 h vs 63.5 ± 9.2 h, P < 0.001), shorter urinary drainage time (6.5 ± 3.4 d vs 7.8 ± 1.3 d, P < 0.001), 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. CONCLUSION: 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.

Mechanical evaluation of three access devices for laparoendoscopic single-site surgery.

BACKGROUND: Many access devices have been developed for laparoendoscopic single-site surgery (LESS) during recent years. However, investigations are needed to determine which port is most suitable for this relatively new technique. The aim of this study was to evaluate commonly used ports using mechanical approaches in a training simulator. Any port that required less force and shorter surgery times had superior maneuverability. METHODS: The following three commercially available access devices were evaluated: Multi-ports, TriPort, and single-incision laparoscopic surgery (SILS) Port. A LESS mechanical evaluation platform was developed to investigate the forces that acted on the instruments in the ports while moving along horizontal and vertical axes. In addition, a strain-force measurement system was used to compare the average load on the ports when performing standard maneuvers. Additionally, the task completion time was recorded when the maneuvers in these ports were completed. RESULTS: During the horizontal displacement of the instrument, the traction forces of the Multi-ports were lower than those of the SILS Port, which were lower than those of the TriPort. The average traction forces were significantly different in pairwise multiple comparisons (P < 0.05). When the instrument was inserted into the ports, the vertical friction forces of the Multi-ports were the lowest and those of the TriPort were the highest. On extraction of the instrument, the friction forces of the Multi-ports remained the lowest, followed by those of the TriPort and SILS Port. There were statistically significant results among all the devices (P < 0.05). The average load required to perform the task was less for the SILS Port than that for the TriPort (P < 0.05). Similarly, the average load for the Multi-ports was significantly less than that for the TriPort (P < 0.001). The participants who used the Multi-ports had significantly faster task times than those who used the SILS Port or TriPort (P < 0.005). CONCLUSIONS: Compared with the TriPort and SILS Port, the Multi-ports was associated with the least average load and the shortest task performance times in a training simulator. This study demonstrates that the Multi-ports may offer superior maneuverability for LESS.

Dimethyl 2,5-bis-(5-hexyl-thio-phen-2-yl)benzene-1,4-dioate.

In the title compound, C(30)H(38)O(4)S(2), the centroid of the benzene ring lies on a center of inversion. The thio-phene ring is aligned at 49.8 (1)° with respect to the benzene ring. The alkyl chain adopts an extended zigzag conformation.

Synthesis of tetrachloro-azapentacene as an ambipolar organic semiconductor with high and balanced carrier mobilities.

Two new azapentacene derivatives 9,10-dibromo-6,13-bis(triisopropylsilylethynyl)-1-azapentacene (a) and 8,9,10,11-tetrachloro-6,13-bis(triisopropylsilylethynyl)-1-azapentacene (b) were synthesized, and their FET properties were investigated. Compound b exhibits high and balanced ambipolar transport properties, with the hole and electron mobilities reaching up to 0.12 and 0.14 cm(2) V(-1) s(-1), respectively. This work suggests that chlorination to the N-heteropentacene framework is an efficient way for producing high performance ambipolar organic semiconductors.

High and balanced hole and electron mobilities from ambipolar thin-film transistors based on nitrogen-containing oligoacences.

We demonstrate a strategy for designing high-performance, ambipolar, acene-based field-effect transistor (FET) materials, which is based on the replacement of C-H moieties by nitrogen atoms in oligoacenes. By using this strategy, two organic semiconductors, 6,13-bis(triisopropylsilylethynyl)anthradipyridine (1) and 8,9,10,11-tetrafluoro-6,13-bis(triisopropylsilylethynyl)-1-azapentacene (3), were synthesized and their FET characteristics studied. Both materials exhibit high and balanced hole and electron mobilities, 1 having µ(h) and µ(e) of 0.11 and 0.15 cm(2)/V·s and 3 having µ(h) and µ(e) of 0.08 and 0.09 cm(2)/V·s, respectively. The successful demonstration of high and balanced ambipolar FET properties from nitrogen-containing oligoacenes opens up new opportunities for designing high-performance ambipolar organic semiconductors.

New oligothiophene-pentacene hybrids as highly stable and soluble organic semiconductors.

Two series of new oligothiophene-pentacene hybrid compounds were successfully synthesized and characterized, which consist of pentacene and anthradithiophene skeletons modified by different oligothienyl groups at 6,13 sites or 5,11 sites, respectively. Their optical, thermal, and electrochemical properties show regular variations with the length change of the side groups. These materials exhibit much higher solubility and significantly improved thermal and photooxidation stabilities compared with unmodified pentacene and anthradithiophene.