Coronavirus disease 2019 (COVID-19), the global pandemic caused by SARS-CoV-2, has resulted thus far in greater than 933,000 deaths worldwide; yet disease pathogenesis remains unclear. Clinical and immunological features of patients with COVID-19 have highlighted a potential role for changes in immune activity in regulating disease severity. However, little is known about the responses in human lung tissue, the primary site of infection. Here we show that pathways related to neutrophil activation and pulmonary fibrosis are among the major up-regulated transcriptional signatures in lung tissue obtained from patients who died of COVID-19 in Wuhan, China. Strikingly, the viral burden was low in all samples, which suggests that the patient deaths may be related to the host response rather than an active fulminant infection. Examination of the colonic transcriptome of these patients suggested that SARS-CoV-2 impacted host responses even at a site with no obvious pathogenesis. Further proteomics analysis validated our transcriptome findings and identified several key proteins, such as the SARS-CoV-2 entry-associated protease cathepsins B and L and the inflammatory response modulator S100A8/A9, that are highly expressed in fatal cases, revealing potential drug targets for COVID-19.

Systemic immune-inflammation index (SII), based on lymphocyte (L), neutrophil (N), and platelet (P) counts, was recently developed and reflects comprehensively the balance of host inflammatory and immune status. We explored its prognostic value in localized gastric cancer (GC) after R0 resection and the potential associations with Thymidine phosphorylase (TYMP), which was reported to increase the migration and invasion of gastric cancer cells. A total of 455 GC patients who received D2 gastrectomy were enrolled. Blood samples were obtained within 1 week before surgery to measure SII (SII = P × N/L). TYMP expression was measured on tumor sections by immunohistochemical analysis. Preoperative high SII indicated worse prognosis (HR: 1.799; 95% CI: 1.174-2.757; p = 0.007) in multivariate analysis and was associated with higher pathological TNM stage, deeper local invasion of tumor and lymph node metastasis (all p < 0.001). SII predicted poor overall survival in pathological TNM stage I subgroup also (p < 0.001). Furthermore we found that in high SII group, positive rate of TYMP expression increased (53.7% vs 42.7%, p = 0.046) and TYMP positive patients had higher SII score (median 405.9 vs. 351.9, p = 0.026). SII, as a noninvasive and low cost prognostic marker, may be helpful to identify higher-risk patients after R0 resection, even for stage I GC patients.

Angiosarcoma is a rare malignant mesenchymal tumor with poor prognosis. We aimed to identify malignancy-associated miRNAs and their target genes, and explore biological functions of miRNA and its target in angiosarcoma. By miRNA microarrays and reverse transcription polymerase chain reaction, we identified 1 up-regulated miRNA (miR-222-3p) and 3 down-regulated miRNAs (miR-497-5p, miR-378-3p and miR-483-5p) in human angiosarcomas compared with human capillary hemangiomas. The intermediate-conductance calcium activated potassium channel KCa3.1 was one of the putative target genes of miR-497-5p, and marked up-regulation of KCa3.1 was detected in angiosarcoma biopsy specimens by immunohistochemistry. The inverse correlation of miR-497-5p and KCa3.1 also was observed in the ISO-HAS angiosarcoma cell line at the mRNA and protein levels. The direct targeting of KCa3.1 by miR-497-5p was evidenced by reduced luciferase activity due to complementary binding of miR-497-5p to KCa3.1 mRNA 3′ untranslated region. For the functional role of miR-497-5p/KCa3.1 pair, we showed that application of TRAM-34, a specific KCa3.1 channel blocker, or transfection of ISO-HAS cells with KCa3.1 siRNA or miR-497-5p mimics inhibited cell proliferation, cell cycle progression, and invasion by down-regulating cell-cycle related proteins including cyclin D1, surviving and P53 and down-regulating matrix metallopeptidase 9. In an in vivo angiosarcoma xenograft model, TRAM-34 or miR-497-5p mimics both inhibited tumor growth. In conclusion, the tumor suppressor miR-497-5p down-regulates KCa3.1 expression and contributes to the inhibition of angiosarcoma malignancy development. The miR-497-5p or KCa3.1 might be potential new targets for angiosarcoma treatment.