The prognostic significance of CDKN2A homozygous deletion in IDH-mutant lower-grade glioma and glioblastoma: a systematic review of the contemporary literature

Journal of Neuro-Oncology - The most recent cIMPACT-NOW update highlighted the homozygous deletion of the Cyclin Dependent Kinase Inhibitor 2A (CDKN2A) gene as a clinically important molecular...     

Impaired anti-SARS-CoV-2 antibody response in non-severe COVID-19 patients with diabetes mellitus: A preliminary report

Background and aimsPatients with diabetes mellitus (DM) often demonstrate impaired antibody response to influenza/hepatitis B vaccines. Hence, we compared anti-SARS-CoV-2 antibody response in non-severe COVID-19 patients with and without type 2 diabetes mellitus (T2DM).MethodsRecords of non-severe COVID-19 patients admitted at our institution between April 10, 2020 and May 20, 2020 were retrieved. Qualitative detection of total (IgG + IgM) anti-SARS-CoV-2 antibody was performed using electrochemiluminescence immunoassay in plasma samples collected at least 14 days post-polymerase chain reaction (PCR) confirmation of diagnosis.ResultsThirty-one non-severe COVID-19 patients were included. Nine patients (29%) had T2DM with mean HbA_1c at admission of 8.3 ± 1.0%. Anti-SARS-CoV-2 antibody was estimated at a median of 16 (14–17) days post-PCR confirmation of COVID-19 diagnosis. Only three patients (10%) were seronegative, and all had T2DM. Patients with T2DM were more likely to have non-detectable anti-SARS-CoV-2 antibodies than those without DM (p = 0.019).ConclusionsCOVID-19 patients with T2DM may not undergo seroconversion even after two weeks of diagnosis. Impaired seroconversion could theoretically increase the risk of reinfections in patients with DM. However, the finding requires validation in large-scale studies involving serial estimations of anti-SARS-CoV-2 antibodies in patients with and without DM.     

Exosomes secreted by prostate cancer cells under hypoxia promote matrix metalloproteinases activity at pre-metastatic niches

Approximately, 30 000 men die from prostate cancer (PCa) every year in the United States, mainly due to the metastasis. Thus, the key events associated with PCa metastasis are under rigorous investigation, with recent studies showing that preparation of pre-metastatic niches (PMN) in distant organs is an important step. However, the molecular basis for PMN preparation is still unclear. Hypoxia in primary tumors promotes aggressiveness; however, its precise role in metastasis is not clear. We recently reported that exosomes secreted by PCa cells under hypoxia promote stemness and invasiveness in naïve PCa cells; however, whether these extracellular vesicles also influence PMN remains unknown. In the present study, we isolated exosomes from human PCa PC3 cells under normoxic (21% O₂, exosomes secreted under normoxic condition [Exo^Normoxic]) and hypoxic (1% O₂, exosomes secreted under hypoxic condition [Exo^Hypoxic]) conditions, and characterized their effect (10 µg exosomes, intraperitoneal (IP) treatment every 48 hours for 4 weeks) on key biomarkers associated with PMN in nude mice. Whole animal fluorescence imaging showed that Exo^Hypoxic treatment promotes matrix metalloproteinases (MMPs) activity in several putative metastatic sites. Histological studies confirmed that Exo^Hypoxic treatment enhanced the level of MMP2, MMP9, and extracellular matrix proteins (fibronectin and collagen) as well as increased the number of CD11b+ cells at selective PMN sites. Furthermore, proteomic profiling of exosomes by liquid chromatography/mass spectrometry identified cargo proteins in Exo^Normoxic and Exo^Hypoxic as well as distinct canonical pathways targeted by them. These results suggest that exosomes secreted by PCa cells under hypoxia plausibly remodel distant PMN, and thus, could be a potential target to control metastatic PCa.