Highlights The IgA and IgE levels increased significantly, while C3 level decreased in non-survivors. Decreased complement C3 level was correlated with increased odds of death. Low level of C3 may be an alert to the attending that patients may be of additional management. Inhibition of the complement pathway might be an effective therapeutic to COVID-19 patients.

BackgroundsProficient-mismatch-repair or microsatellite stability (pMMR/MSS) colorectal cancer (CRC) has limited efficacy for immune checkpoint blockade (ICB) therapy and its underlying mechanism remains unclear. Guanylate binding protein 2 (GBP2) is a member of the GTPase family and is crucial to host immunity against pathogens. However, the correlations between GBP2 and immunosurveillance and immunotherapy for pMMR/MSS CRC have not been reported.MethodsUnsupervised clustering was employed to classify immune class and non-immune class in 1424 pMMR/MSS patients from six independent public datasets. This binary classification was validated using immune cells or response related signatures. The correlation between GBP2 and immune microenvironment was explored using well-established biological algorithms, multiplex immunohistochemistry (mIHC), in vitro and in vivo experiments.ResultsWe classified 1424 pMMR/MSS CRC patients into two classes, ‘immune’ and ‘non-immune’, and GBP2 was identified as a gene of interest. We found that lower GBP2 expression was correlated with poor prognosis and metastasis. GBP2 expression was also upregulated in the immune class and highly associated with interferon-γ (IFN-γ) signaling pathway and CD8 +T cell infiltration using gene set enrichment analysis, gene ontology analysis, single-cell sequencing and mIHC. Moreover, reduced GBP2 expression inhibited the antigen processing and presentation machinery and CXCL10/11 expression in MSS CRC cells on IFN-γ stimulation. A Transwell assay revealed that deletion of GBP2 in murine MSS CRC cells reduced CD8 +T cell migration. Mechanistically, GBP2 promoted signal transducer and transcription activator 1 (STAT1) phosphorylation by competing with SHP1 for binding to STAT1 in MSS CRC cells. Finally, an unsupervised subclass mapping (SubMap) algorithm showed that pMMR/MSS patients with high GBP2 expression may correlate with a favorable response to anti-PD-1 therapy. We further confirmed that GBP2 knockout reduced CD8 +T cell infiltration and blunted the efficacy of PD-1 blockade in tumor-bearing mice.ConclusionsOur study reveals that pMMR/MSS CRC is immunogenically heterogeneous and that GBP2 is a promising target for combinatorial therapy with ICB.

Hemorrhagic chronic radiation proctopathy (CRP) is a common complication after pelvic radiotherapy in patients with prostate or gynecological cancers. This systematic review was conducted to evaluate the efficacy and safety of argon plasma coagulation (APC) in treating hemorrhagic CRP. The databases of PubMed, Embase, and Cochrane Library were searched for related studies from inception to July 2017. Finally, 33 studies were identified with a total of 821 hemorrhagic CRP patients. After APC treatment, hemoglobin levels increased from 7.7–13.4 g/L to 11–14 g/L (including 15 studies). All (n = 33) studies reported an effective rate in rectal bleeding, among which five studies had a rate of 100%. Short-term complications were reported in 31 studies, while long-term complications in 33 studies and no complication in 11 studies. As for the severe complications, perforation was reported by 2 out of 33 studies, and the incidences were 3.3% (1/30) and 3.7% (1/27), respectively. As for APC setting, argon gas flow rate (median 1.5 L/min) and electric power (median 50 W) had no significant influence on complications and hemostasis. In conclusion, current literature indicated that APC therapy was an effective and safe strategy for hemorrhagic CRP, and large-scale prospective studies are needed to warrant our study.

: Heat shock protein 90 (Hsp90) plays an essential role in various physiological and pathological processes. It activates client proteins to participate in tumor progression. Blocking Hsp90 could enable effective antitumor effects in many tumor types, such as multiple myeloma and colon cancer. Recently, it has motivated an interest in Hsp90 inhibitors that bind to the N-terminal or C-terminal ATP pocket as antitumor drugs. We reviewed the data from experimental and clinical trials on Hsp90 inhibitors in the treatment of different malignancies to explore and summarize their antitumor mechanisms.

COVIDTrach is a UK multidisciplinary collaborative project that aims to evaluate the outcomes of tracheostomy in COVID-19 patients. It also examines the implementation of national guidance in COVID-19 tracheostomies and the incidence of COVID-19 infections amongst those health care workers involved in the procedure. An invitation to participate in an online survey tool (REDCap) was disseminated to all UK NHS departments involved in tracheostomy in mechanically ventilated COVID-19 patients via the Federation of Surgical Specialty Associations, it's subsidiary organisations and the Intensive Care Society. To date 78 hospitals have submitted 564 COVID-19 tracheostomy cases. Fifty-two percent (n=219/465) of patients who had undergone tracheostomy and were still alive, had been successfully weaned from mechanical ventilation at the point of completing the survey. The all cause in-hospital mortality following tracheostomy was 12% (n=62/530), with 3% of these (n=2/62) due to tracheostomy related complications and the remaining deaths due to COVID-19 related complications. Amongst 400 cases submitting data two weeks after the tracheostomy, no instance of COVID-19 infection amongst operators was recorded. FFP3 masks or Powered Air Purifying Respirators were used by operators in 100% of tracheostomies and a face visor or hood with face shield was available in 99% of cases. This interim report highlights early outcomes following tracheostomy in mechanically ventilated COVID-19 patients. Future reporting from COVIDTrach will include more detailed analysis at later timepoints using comparator groups in order to provide a more comprehensive assessment of tracheostomy in COVID-19.