Synthesis of carbon-11-labeled tricyclic necroptosis inhibitors as new potential PET agents for imaging of tumor necrosis factor alpha (TNF-alpha)

Imaging Infection Across Scales of Size: From Whole Animals to Single Molecules

Infectious diseases are a leading cause of global morbidity and mortality, and the threat of infectious diseases to human health is steadily increasing as new diseases emerge, existing diseases reemerge, and antimicrobial resistance expands. The application of imaging technology to the study of infection biology has the potential to uncover new factors that are critical to the outcome of host-pathogen interactions and to lead to innovations in diagnosis and treatment of infectious diseases. This article reviews current and future opportunities for the application of imaging to the study of infectious diseases, with a particular focus on the power of imaging objects across a broad range of sizes to expand the utility of these approaches. Expected final online publication date for the Annual Review of Microbiology, Volume 75 is October 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Design and Synthesis of New 6-Nitro and 6-Amino-3,3a,4,5-Tetrahydro-2H-Benzo[g]indazole Derivatives: Antiproliferative and Antibacterial Activity

New substituted benzo[g]indazoles functionalized with a 6-nitro and 6-amino groups have been synthesized by the reaction of benzylidene tetralones with hydrazine in acetic acid. The resulting conformationally-constrained compounds were evaluated for their antiproliferative activity against selected cancer cell lines. The nitro-based indazoles 11a, 11b, 12a and 12b have shown IC₅₀ values between 5–15 μM against the lung carcinoma cell line NCI-H460. Moreover, the nitro compounds were tested for antibacterial activity where compounds 12a and 13b have shown MIC values of 250 and 62.5 μg/mL against N. gonorrhoeae with no hemolytic activity in human red blood cells (RBC).

PET imaging of inflammation biomarkers

Inflammation plays a significant role in many disease processes. Development in molecular imaging in recent years provides new insight into the diagnosis and treatment evaluation of various inflammatory diseases and diseases involving inflammatory process. Positron emission tomography using (18)F-FDG has been successfully applied in clinical oncology and neurology and in the inflammation realm. In addition to glucose metabolism, a variety of targets for inflammation imaging are being discovered and utilized, some of which are considered superior to FDG for imaging inflammation. This review summarizes the potential inflammation imaging targets and corresponding PET tracers, and the applications of PET in major inflammatory diseases and tumor associated inflammation. Also, the current attempt in differentiating inflammation from tumor using PET is also discussed.

BCL2 suppresses PARP1 function and nonapoptotic cell death

BCL2 suppresses apoptosis by binding the BH3 domain of proapoptotic factors and thereby regulating outer mitochondrial membrane permeabilization. Many tumor types, including B-cell lymphomas and chronic lymphocytic leukemia, are dependent on BCL2 for survival but become resistant to apoptosis after treatment. Here, we identified a direct interaction between the antiapoptotic protein BCL2 and the enzyme PARP1, which suppresses PARP1 enzymatic activity and inhibits PARP1-dependent DNA repair in diffuse large B-cell lymphoma cells. The BH3 mimetic ABT-737 displaced PARP1 from BCL2 in a dose-dependent manner, reestablishing PARP1 activity and DNA repair and promoting nonapoptotic cell death. This form of cell death was unaffected by resistance to single-agent ABT-737 that results from upregulation of antiapoptotic BCL2 family members. On the basis of the ability of BCL2 to suppress PARP1 function, we hypothesized that ectopic BCL2 expression would kill PARP inhibitor-sensitive cells. Strikingly, BCL2 expression reduced the survival of PARP inhibitor-sensitive breast cancer and lung cancer cells by 90% to 100%, and these effects were reversed by ABT-737. Taken together, our findings show that a novel interaction between BCL2 and PARP1 blocks PARP1 enzymatic activity and suppresses PARP1-dependent repair. Targeted disruption of the BCL2-PARP1 interaction therefore may represent a potential therapeutic approach for BCL2-expressing tumors resistant to apoptosis.