Intratumoral hypoxia and expression of hypoxia-inducible factor-1α (HIF-1α) correlate with metastasis and poor survival in patients with sarcoma. We show here that hypoxia controls sarcoma metastasis through a novel mechanism wherein HIF-1α enhances expression of the intracellular enzyme procollagen-lysine, 2-oxoglutarate 5-dioxygenase 2 (PLOD2). We show that loss of HIF-1α or PLOD2 expression disrupts collagen modification, cell migration, and pulmonary metastasis (but not primary tumor growth) in allograft and autochthonous LSL-Kras^G12D/+; Trp53^fl/fl murine sarcoma models. Furthermore, ectopic PLOD2 expression restores migration and metastatic potential in HIF-1α–deficient tumors, and analysis of human sarcomas reveals elevated HIF1A and PLOD2 expression in metastatic primary lesions. Pharmacologic inhibition of PLOD enzymatic activity suppresses metastases. Collectively, these data indicate that HIF-1α controls sarcoma metastasis through PLOD2-dependent collagen modification and organization in primary tumors. We conclude that PLOD2 is a novel therapeutic target in sarcomas and successful inhibition of this enzyme may reduce tumor cell dissemination. Significance: Undifferentiated pleomorphic sarcoma (UPS) is a commonly diagnosed and particularly aggressive sarcoma subtype in adults, which frequently and fatally metastasizes to the lung. Here, we show the potential use of a novel therapeutic target for the treatment of metastatic UPS, specifically the collagen-modifying enzyme PLOD2. Cancer Discov; 3(10); 1190–1205. ©2013 AACR. See related commentary by Vanharanta and Massagué, p. 1103 This article is highlighted in the In This Issue feature, p. 1083

Excessive production of proinflammatory cytokines, particularly tumor necrosis factor-α (TNFα) and interleukin-1β (IL-1β), plays a critical role in septic shock induced by bacterial endotoxin (endotoxemia). Precise control of cytokine expression depends on rapid degradation of cytokine mRNAs, mediated by an AU-rich element (ARE) in the 3′ noncoding region and by interacting ARE-binding proteins, which control the systemic inflammatory response. To understand the function of the ARE-binding protein AUF1, we developed anAUF1knockout mouse. We show that AUF1 normally functions to protect against the lethal progression of endotoxemia. Upon endotoxin challenge,AUF1knockout mice display symptoms of severe endotoxic shock, including vascular hemorrhage, intravascular coagulation, and high mortality, resulting from overproduction of TNFα and IL-1β. Overexpression of these two cytokines is specific, and shown to result from an inability to rapidly degrade these mRNAs in macrophages following induction. Neutralizing antibodies to TNFα and IL-1β protectAUF1knockout mice against lethal endotoxic shock. These and other data describe a novel post-transcriptional mechanism whereby AUF1 acts as a crucial attenuator of the inflammatory response, promoting the rapid decay of selective proinflammatory cytokine mRNAs following endotoxin activation. Defects in the AUF1 post-transcriptionally controlled pathway may be involved in human inflammatory disease.

Objectives: To report methods and findings of 2 autopsies with molecular evaluation of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) positive individuals. Methods: Postmortem examination was completed following Centers for Disease Control and Prevention public guidelines. Numerous formalin-fixed paraffin-embedded (FFPE) tissue types from each case were surveyed for SARS-CoV-2 RNA by quantitative reverse transcription polymerase chain reaction (qRT-PCR). SARS-CoV-2 viral genome was sequenced by next-generation sequencing (NGS) from FFPE lung tissue blocks. Results: Postmortem examinations revealed diffuse alveolar damage, while no viral-associated hepatic, cardiac, or renal damage was observed. Viral RNA was detected in lungs, bronchi, lymph nodes, and spleen in both cases using qRT-PCR method. RNA sequencing using NGS in case 1 revealed mutations most consistent with Western European Clade A2a with ORF1a L3606F mutation. Conclusions: SARS-CoV-2 testing and viral sequencing can be performed from FFPE tissue. Detection and sequencing of SARS-CoV-2 in combination with morphological findings from postmortem tissue examination can aid in gaining a better understanding of the virus’s pathophysiologic effects on human health.

Mice lacking heterogenous nuclear ribonuclear protein D (Hnrnpd), also known as Auf1, a regulator of inflammatory cytokine mRNA stability, develop chronic dermatitis with age that is characterized by pruritis and excoriations. Histological analysis showed marked epidermal acanthosis and spongiosis, neovascularization, and elevated number of inflammatory cells, including T cells, macrophages, neutrophils, mast cells, and eosinophils. Hnrnpd-deficient (Hnrnpdtm1Rjsc) mice with dermatitis display elevated serum IgE levels. Lesions in Hnrnpdtm1Rjsc mice were associated with a shift towards a Th₂ immune environment. Evaluation of T-cell-mediated skin inflammation by assaying contact hypersensitivity indicated an increased response in Hnrnpdtm1Rjsc mice. T cells and macrophages from Hnrnpdtm1Rjsc mice demonstrate a number of abnormalities associated with dermatitis, including increased IL2, tumor-necrosis factor-α (TNFα), and IL1β production. Finally, many features of spontaneous dermatitis could be recapitulated in experimentally induced lesions by subcutaneous injection of CCL27 and TNF in unaffected Hnrnpdtm1Rjsc mice. Collectively, these data highlight the importance of HNRNPD and proper regulation of mRNA stability in the intricate processes of leukocyte recruitment and inflammatory activation within the skin.