Cellular Based Aggregated Satellite System: The Design and Architecture of a Three Degree of Freedom Near-Frictionless Testbed for Ground Validation of CubeSat Operations

As small and nano-satellite operations become more complex and increase in functionality, the need to validate new concepts prior to deployment in a low-cost and time efficient manner has further increased. While computer simulations have traditionally provided acceptable results for guidance navigation and control (GNC) algorithms, more complex actions such as rendezvous and proximity operations and docking (RPOD) require alternative methods, which often require ground-based platforms. The concept of on-orbit autonomous docking of small satellites has grown in popularity due to its broad range of applications. However, most existing ground testing platforms (GTP) are expensive due to the technologies used and large physical space required. Due to the importance of RPOD to nano-satellites specifically, the development of a low-profile GTP is a crucial component in the testing and validation of small satellite concepts. The Space Engineering Research Center (SERC) at the University of Southern California (USC) has designed and manufactured a GTP capable of validating various unique nano-satellite operations in a cost-effective and space-efficient manner. This paper will focus on the design and architecture of a three degree of freedom (3DoF) near-frictionless testbed for ground validation of RPOD in a microgravity environment and its use with various small satellite applications

BRAFV600E/RAS Mutations and Lynch Syndrome in Patients With MSI-H/dMMR Metastatic Colorectal Cancer Treated With Immune Checkpoint Inhibitors

Mutació BRAF; Síndrome de Lynch; Inhibidors del punt de control immunològicMutación BRAF; Síndrome de Lynch; Inhibidores de punto de control inmunológicoBRAF mutation; Lynch syndrome; Immune checkpoint inhibitorsBackground We pooled data from 2 cohorts of immune checkpoint inhibitors-treated microsatellite instability-high/mismatch repair-deficient (MSI/dMMR) metastatic colorectal cancer patients to evaluate the prognostic value of RAS/BRAFV600E mutations and Lynch syndrome (LS). Patients and Methods Patients were defined as LS-linked if germline mutation was detected and as sporadic if loss of MLH1/PMS2 expression with BRAFV600E mutation and/or MLH1 promoter hypermethylation, or biallelic somatic MMR genes mutations were found. Progression-free survival (PFS) and overall survival (OS) were adjusted on prognostic modifiers selected on unadjusted analysis (P < .2) if limited number of events. Results Of 466 included patients, 305 (65.4%) and 161 (34.5%) received, respectively, anti-PD1 alone and anti-PD1+anti-CTLA4 in the total population, 111 (24.0%) were treated in first-line; 129 (28.8%) were BRAFV600E-mutated and 153 (32.8%) RAS-mutated. Median follow-up was 20.9 months. In adjusted analysis of the whole population (PFS/OS events = 186/133), no associations with PFS and OS were observed for BRAFV600E-mutated (PFS HR= 1.20, P = .372; OS HR = 1.06, P = .811) and RAS-mutated patients (PFS HR = 0.93, P = .712, OS HR = 0.75, P = .202). In adjusted analysis in the Lynch/sporadic status-assigned population (n = 242; PFS/OS events = 80/54), LS-liked patients had an improved PFS compared to sporadic cases (HR = 0.49, P = .036). The adjusted HR for OS was 0.56 with no significance (P = .143). No adjustment on BRAFV600E mutation was done due to collinearity. Conclusion In this cohort, RAS/BRAFV600E mutations were not associated with survival while LS conferred an improved PFS.This research did not receive any specific grant from funding of industry; partially funded by IOVIRCCS 5x1000 Grant, Missoni Project, code BIGID219ZAGO, and by Association de Recherche en Oncologie Saint-Antoine (AROSAT)

Initiation of Human Immunodeficiency Virus Type 1 (HIV-1) Transcription is Inhibited by Noncytolytic CD8+ Suppression

The replication of human immunodeficiency virus type 1 (HIV-1) can be inhibited by noncytolytic CD8+ T cell mediated suppression, an immune response that specifically targets HIV-1 gene expression. Clinical studies demonstrate that this immune response may play an important role in the host defense against HIV infection. In this study, we examined the distinct steps in viral gene expression for inhibition by noncytolytic CD8+ T cells. A primary HIV-1 infection system of CD4+ enriched peripheral blood mononuclear cells was utilized to examine the HIV-1 life cycle as a relevant ex vivo system. Established CD8+ T cell lines from two HIV+ long-term nonprogressors were used to examine differences at the level of transcriptional initiation and elongation of the HIV genome. This infection system coupled with the results from real-time measurement of newly transcribed RNA transcripts determined that there was a significant decrease (5-8 fold) in short intracellular viral RNA transcripts. These data strongly favor a role for the initiation of virus transcription in noncytolytic CD8+ T cell mediated suppression

Association of CpG island methylator phenotype and EREG/AREG methylation and expression in colorectal cancer

BACKGROUND: High EREG and AREG expression, and left-sided primary tumours are associated with superior efficacy of anti-epidermal growth factor receptor (EGFR) therapy in metastatic colorectal cancer (CRC), but a unifying explanation of these findings is lacking. METHODS: RNA-seq, gene expression arrays, and DNA methylation profiling were completed on 179 CRC tumours. Results were validated using independent The Cancer Genome Atlas data sets. An independent cohort of 198 KRAS wild-type metastatic CRC tumours was tested for CpG island methylator phenotype (CIMP) status, and progression-free survival (PFS) with the first anti-EGFR regimen was retrospectively determined. RESULTS: EREG and AREG expression was highly inversely correlated with methylation and was inversely associated with right-sided primary tumour, BRAF mutation, and CIMP-high status. Treatment of CRC cell lines with hypomethylating agents decreased methylation and increased expression of EREG. Inferior PFS with anti-EGFR therapy was associated with CIMP-high status, BRAF mutation, NRAS mutation, and right-sided primary tumour on univariate analysis. Among known BRAF/NRAS wild-type tumours, inferior PFS remained associated with CIMP-high status (median PFS 5.6 vs 9.0 mo, P=0.023). CONCLUSIONS: EREG and AREG are strongly regulated by methylation, and their expression is associated with CIMP status and primary tumour site, which may explain the association of primary tumour site and EREG/AREG expression with anti-EGFR therapy efficacy

Goblet Cell Tumors of the Appendix: Clinical & Molecular Features

View full abstracthttps://openworks.mdanderson.org/leading-edge/1047/thumbnail.jp

Utility of plasma tumor marker levels in management of patients with appendiceal adenocarcinoma

View full abstracthttps://openworks.mdanderson.org/leading-edge/1049/thumbnail.jp

Randomized, phase II selection study of ramucirumab and paclitaxel versus FOLFIRI in refractory small bowel adenocarcinoma: SWOG S1922

Background: Small bowel adenocarcinoma is a rare malignancy with limited evidence to support the choice of systemic chemotherapy beyond the frontline setting. Though second-line therapy has historically been extrapolated from colorectal cancers, recent molecular data has demonstrated small bowel adenocarcinoma to be genomically unique when compared to either colon or gastric cancer. Retrospective analyses of irinotecan- and taxane-based therapies and one prospective phase II clinical trial of nab-paclitaxel have demonstrated clinical activity in this cancer. Ramucirumab/paclitaxel represents an active combination in the management of gastric cancer. SWOG 1922 evaluates the use of FOLFIRI or ramucirumab/paclitaxel in the second- and later-line setting for small bowel adenocarcinoma. Methods: This is randomized, phase II, selection design clinical trial of FOLFIRI (5-fluorouracil, leucovorin and irinotecan) every two weeks or ramucirumab D1,15 and paclitaxel D1,8,15 every 4 weeks with the primary endpoint of progression-free survival (PFS). Secondary endpoints include response rate, overall survival, and safety. Archived paraffin tumor tissue collection and serial blood collections are included for correlative analyses. Key eligibility criteria include having mismatch repair proficient/microsatellite stable small bowel adenocarcinoma (ampullary location excluded); metastatic or locally advanced unresectable disease; prior fluoropyrimidine and/or oxaliplatin therapy; no prior treatment with irinotecan, ramucirumab, or taxanes; no recent bleeding, blood clots, or bowel perforation/fistula; and Zubrod performance status of 0/1. Measurable disease is not required. The null hypothesis is median PFS of 2.5 months. If a median PFS of at least 3.5 months is observed in one or both arms, the goal is to choose the better regimen with respect to this endpoint. The design provides a 90% probability of selecting the more active arm, assuming a hazard ratio of 1.4, if both arms meet this threshold. This trial is open and, as of September 1, 2021, 21 of 94 planned patients have been enrolled

Ampullary cancers harbor ELF3 tumor suppressor gene mutations and exhibit frequent WNT dysregulation

The ampulla of Vater is a complex cellular environment from which adenocarcinomas arise to form a group of histopathologically heterogenous tumors. To evaluate the molecular features of these tumors, 98 ampullary adenocarcinomas were evaluated and compared to 44 distal bile duct and 18 duodenal adenocarcinomas. Genomic analyses revealed mutations in the WNT signaling pathway among half of the patients and in all three adenocarcinomas irrespective of their origin and histological morphology. These tumors were characterized by a high frequency of inactivating mutations of ELF3, a high rate of microsatellite instability, and common focal deletions and amplifications, suggesting common attributes in the molecular pathogenesis are at play in these tumors. The high frequency of WNT pathway activating mutation, coupled with small-molecule inhibitors of β-catenin in clinical trials, suggests future treatment decisions for these patients may be guided by genomic analysis