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Background: Angiosarcomas are rare mesenchymal sarcomas that can present as primary cutaneous or noncutaneous disease. They express a variety of vascular endothelial growth factor receptors. The authors hypothesized that the treatment of angiosarcoma with pazopanib, a multikinase inhibitor with activity against vascular endothelial growth factor receptors, would result in disease response and prolonged disease stabilization.Methods: This was an open-label, phase 2 trial of pazopanib in patients who had incurable angiosarcoma. The co-primary end points were response according to the Response Evaluation Criteria in Solid Tumors and progression-free survival (PFS) at 3 months. The starting dose of pazopanib was 800 mg daily.Results: Twenty-nine patients were accrued between 2011 and 2018, and 22 patients were evaluable for response. Toxicities were similar to those identified in prior reports. There was one partial response (3%), and the clinical benefit rate (including complete responses, partial responses, and stable disease) was 48%, which was observed more frequently in patients who had cutaneous disease. The median PFS was 14.4 weeks, and the 3-month PFS rate determined by Kaplan-Meier estimate was 54.6% (95% CI, 36.0%-82.9%), meeting the primary study objective. The Kaplan-Meier overall survival estimate was 16.1 months.Conclusions: Pazopanib therapy in patients who had incurable angiosarcoma was associated with meaningful disease control, especially in those who had cutaneous disease with limited objective responses.Lay Summary: Angiosarcoma is a rare cancer that can be found on the skin or in internal organs. This study tested pazopanib, an oral targeted medication, to determine its benefit in patients with angiosarcoma who could not undergo the removal of their tumors by surgery. Pazopanib treatment was safe, and no new side effects were reported. The study showed that pazopanib controlled tumor growth in one half of patients at 3 months and was more common in angiosarcomas of the skin; it led to tumor shrinkage in a minority of patients (1 of 29). [ABSTRACT FROM AUTHOR]

Regulation of mRNA stability and translation plays a critical role in determining protein abundance within cells. Processing bodies (P‐bodies) are critical regulators of these processes. Here, we report that the Pim1 and 3 protein kinases bind to the P‐body protein enhancer of mRNA decapping 3 (EDC3) and phosphorylate EDC3 on serine (S)161, thereby modifying P‐body assembly. EDC3 phosphorylation is highly elevated in many tumor types, is reduced upon treatment of cells with kinase inhibitors, and blocks the localization of EDC3 to P‐bodies. Prostate cancer cells harboring an EDC3 S161A mutation show markedly decreased growth, migration, and invasion in tissue culture and in xenograft models. Consistent with these phenotypic changes, the expression of integrin β1 and α6 mRNA and protein is reduced in these mutated cells. These results demonstrate that EDC3 phosphorylation regulates multiple cancer‐relevant functions and suggest that modulation of P‐body activity may represent a new paradigm for cancer treatment. Synopsis: EDC3 is highly phosphorylated in tumors, thereby preventing P‐body assembly. Inhibiting EDC3 phosphorylation decreases tumor growth and invasion, suggesting key roles for the regulation of RNA decapping and destruction by EDC3 in cancer progression. The Pim 1 and 3 protein kinases co‐immunoprecipitate with the P‐body protein EDC3 and phosphorylate it at serine 161.Inhibition of EDC3 phosphorylation increases the number of P‐bodies in tumor cells.Inhibition of EDC3 phosphorylation reduces the levels of the integrins B1 and A6 and the transcription factor KLF4.Human breast tumor patient samples contain increased phospho‐EDC3 when compared to normal controls. [ABSTRACT FROM AUTHOR]

Background: Therapeutic options for patients with advanced soft‐tissue sarcoma (STS) are limited. The goal of the current phase 2 study was to examine the clinical activity and safety of the combination of gemcitabine plus pazopanib, a multityrosine kinase inhibitor with activity in STS. Methods: The current randomized, phase 2 trial enrolled patients with advanced nonadipocytic STS who had received prior anthracycline‐based therapy. Patients were assigned 1:1 to receive gemcitabine at a dose of 1000 mg/m2 on days 1 and 8 with pazopanib at a dose of 800 mg daily (G+P) or gemcitabine at a dose of 900 mg/m2 on days 1 and 8 and docetaxel at a dose of 100 mg/m2 on day 8 (G+T) every 3 weeks. Crossover was allowed at the time of disease progression. The study used a noncomparative statistical design based on the precision of 95% confidence intervals for reporting the primary endpoints of median progression‐free survival (PFS) and rate of grade ≥3 adverse events (AEs) for these 2 regimens based on the intent‐to‐treat patient population (AEs were graded using version 4.0 of the National Cancer Institute Common Terminology Criteria for Adverse Events). Results: A total of 90 patients were enrolled: 45 patients on each treatment arm. The median PFS was 4.1 months for each arm (P =.3, log‐rank test). The best overall response of stable disease or better (complete response + partial response + stable disease) was the same for both treatment arms (64% for both the G+T and G+P arms). The rate of related grade ≥3 AEs was 82% for the G+T arm and 78% for the G+P arm. Related grade ≥3 AEs occurring in ≥10% of patients in the G+T and G+P arms were anemia (36% and 20%, respectively), fatigue (29% and 13%, respectively), thrombocytopenia (53% and 49%, respectively), neutropenia (20% and 49%, respectively), lymphopenia (13% and 11%, respectively), and hypertension (2% and 20%, respectively). Conclusions: The data from the current study have demonstrated the safety and efficacy of G+P as an alternative to G+T for patients with nonadipocytic STS. The results of the current trial suggest similar efficacy and tolerability when comparing the gemcitabine and pazopanib (G+P) regimen with the gemcitabine and docetaxel (G+T) regimen. In patients who are not suitable for treatment with G+T, the G+P regimen is a reasonable alternate for the second‐line treatment of patients with metastatic nonadipocytic sarcomas. [ABSTRACT FROM AUTHOR]

The proviral integration site for Moloney murine leukemia virus (PIM) serine/threonine kinases have an oncogenic and prosurvival role in hematological and solid cancers. However, the mechanism by which these kinases drive tumor growth has not been completely elucidated. To determine the genes controlled by these protein kinases, we carried out a microarray analysis in T‐cell acute lymphoblastic leukemia (T‐ALL) comparing early progenitor (ETP‐ALL) cell lines whose growth is driven by PIM kinases to more mature T‐ALL cells that have low PIM levels. This analysis demonstrated that the long noncoding RNA (lncRNA) H19 was associated with increased PIM levels in ETP‐ALL. Overexpression or knockdown of PIM in these T‐ALL cell lines controlled the level of H19 and regulated the methylation of the H19 promoter, suggesting a mechanism by which PIM controls H19 transcription. In these T‐ALL cells, the expression of PIM1 induced stem cell gene expression (SOX2, OCT‐4, and NANOG) through H19. Identical results were found in prostate cancer (PCa) cell lines where PIM kinases drive cancer growth, and both H19 and stem cell gene levels. Small molecule pan‐PIM inhibitors (PIM‐i) currently in clinical trials reduced H19 expression in both of these tumor types. Importantly, the knockdown of H19 blocked the ability of PIM to induce stem cell genes in T‐ALL cells, suggesting a novel signal transduction cascade. In PCa, increases in SOX2 levels have been shown to cause both resistance to the androgen deprivation therapy (ADT) and the induction of neuroendocrine PCa, a highly metastatic form of this disease. Treatment of PCa cells with a small molecule pan‐PIM‐i reduced stem cell gene transcription and enhanced ADT, while overexpression of H19 suppressed the ability of pan‐PIM‐i to regulate hormone blockade. Together, these results demonstrate that the PIM kinases control the level of lncRNA H19, which in turn modifies stem cell gene transcription regulating tumor growth. [ABSTRACT FROM AUTHOR]

To the authors' knowledge, the 2014 Surgeon General's report “The Health Consequences of Smoking‐50 Years of Progress” provides the first large evidence review of the effects of smoking on the outcomes of patients with cancer, concluding that smoking causes adverse health outcomes, increases all‐cause mortality, and increases cancer‐specific mortality. This causal evidence has profound implications on providing high‐quality cancer care by emphasizing the need to address tobacco use in all patients with cancer. [ABSTRACT FROM AUTHOR]

RUNX1 is essential for definitive hematopoiesis and T-cell differentiation. It has been shown that RUNX1 is phosphorylated at specific serine and threonine residues by several kinase families. However, it remains unclear whether RUNX1 phosphorylation is absolutely required for its biological functions. Here, we evaluated hematopoietic activities of RUNX1 mutants with serine ( S)/threonine ( T) to alanine ( A), aspartic acid ( D), or glutamic acid ( E) mutations at phosphorylation sites using primary culture systems. Consistent with the results of knockin mice, RUNX1-2 A, carrying two phospho-deficient mutations at S276 and S293, retained hematopoietic activity. RUNX1-4 A, carrying four mutations at S276, S293, T300, and S303, showed impaired T-cell differentiation activity, but retained the ability to rescue the defective early hematopoiesis of Runx1-deficient cells. Notably, RUNX1-5 A, carrying five mutations at S276, S293, T300, S303, and S462, completely lost its hematopoietic activity. In contrast, the phospho-mimic proteins RUNX1-4 D/ E and RUNX1-5 D/ E exhibited normal function. Our study identifies multiple phosphorylation sites that are indispensable for RUNX1 activity in hematopoiesis. [ABSTRACT FROM AUTHOR]