Objectives: Administrative criteria are often used to define COVID-19 outcomes despite challenges in differentiating hospitalization “for” vs “with” COVID-19 and unknown reliability for identifying COVID-related cardiopulmonary complications. We implemented a protocol to adjudicate COVID-related events across 14 studies participating in C4R. Methods: C4R cohorts ascertained COVID-related hospitalizations and deaths via questionnaires or ongoing surveillance. Medical records were reviewed by C4R physicians using a standardized protocol to assign COVID-related diagnoses as definite or probable. C4R diagnoses were compared against ICD codes assigned to the events. This report includes data from events centrally adjudicated by C4R as of September 2022. Results: Among 144 events ascertained across 7 cohorts as potentially COVID-related, SARS-CoV-2 infection was confirmed in 107/117 (91%) non-fatal hospitalizations and 26/27 (96%) deaths. Of confirmed infections, COVID-19 illness was diagnosed as the cause of 101/107 (94%) hospitalizations and 24/26 (92%) deaths ( Table ). Of non-fatal hospitalizations with infection, 72% were diagnosed with severe or critical COVID-19, 78% with COVID-associated pneumonia, and 29% with renal failure; other complications were less common. C4R review did not validate diagnoses indicated by ICD codes for 1 COVID-19 infection, 5 pneumonias, 1 stroke, and 7 renal failure cases. C4R review did identify diagnoses that were not ICD-coded for 13 infections, 31 pneumonias, 6 myocardial infarctions, 5 venous thromboses, and 21 renal failure cases. Conclusions: Protocolized medical records review by C4R confirmed COVID-19 as the cause of hospitalization or death in 87% of events ascertained as potentially COVID-related and 94% of those in which SARS-CoV-2 infection was confirmed. Both false-positive and false-negative misclassification by ICD criteria was observed. Protocolized review may be useful to identify and validate COVID-related events for epidemiologic research.
Abstract 2658: PFKFB3 inhibition reprograms malignant pleural mesothelioma to glycolytic stress-induced macropinocytosis and ER stress as independent binary adaptive responses
Abstract The metabolic signatures of cancer cells are often associated with elevated glycolysis which promotes alteration in cellular bioenergetics. 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase 3 (PFKFB3), a critical control point in the glycolytic pathway has emerged as a potential anti-cancer target associated with many aspects of neoplastic progression. Pharmacological (PFK158 treatment) and genetic inhibition of PFKFB3 activity, decreases glucose uptake, ATP production, and lactate dehydrogenase activity and inhibits cell proliferation in vitro by arresting the cells in the G0/G1 phase induced cell death in malignant pleural mesothelioma (MPM). It induces an early response of increased macropinocytosis and drastic endosomal vacuolization to overcome the nutrient stress both in sarcomatoid (H28) and epithelioid (EMMeso) MPM cells. Inhibition of PFKFB3 leads to the activation of the endocytic Rac1-Rab5-Rab7 pathway resulting in a unique form of cell death called “methuosis”. Transmission Electron Microscopy analysis showed that pharmacological and genetic inhibition of PFKFB3 activity leads to the formation of nascent macropinocytotic vesicles, which rapidly coalesced to form large vacuoles with compromised lysosomal function. Confocal microscopy revealed F-actin and α-tubulin disassembly leading to the disruption of cell structure integrity. In parallel, PFKFB3 expression inversely modulates endoplasmic reticulum (ER) stress in MPM. Pharmacological and genetic inhibition of PFKFB3 led to an escalation in ER activity and aggravated ER stress mostly by upregulating BiP and GADD153 expression levels. However, EHT1864, a Rac1 inhibitor, could not rescue MPM cells from ER stress, suggesting that the activation of macropinocytosis and ER stress are a result of two independent PFKFB3 modulated adaptive responses. Both immunofluorescence microscopy and co-immunoprecipitation analyses revealed that the two crucial biomolecules of each pathway, Rac1 and Calnexin, interact with each other only at the later stages of PFKFB3 inhibition. Finally, PFK158, in a combination of with CBPt, demonstrated a significant reduction in tumor weight in mesothelin overexpressed EMMeso xenograft model. Since most cancer cells exhibit an increased glycolytic rate, these results provide evidence for PFK158, in combination with standard chemotherapy, may have a potential in the treatment of MPM. Citation Format: Sayantani Sarkar Bhattacharya, Ling Jin, Debarshi Roy, Deokbeom Jung, Prabhu Thirusangu, Yinan Xiao, Julie Staub, Julian Molina, Viji Shridhar. PFKFB3 inhibition reprograms malignant pleural mesothelioma to glycolytic stress-induced macropinocytosis and ER stress as independent binary adaptive responses [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2658.