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An 83-year-old female had asymptomatic SARS-CoV-2 infection while taking ruxolitinib. She remained RT-PCR positive for viral RNA for >120 days, and Pegylated interferon for 4 weeks led to viral RNA clearance. The observations support combination therapy of ruxolitinib + interferon for COVID-19.

An 83-year-old female had asymptomatic SARS-CoV-2 infection while taking ruxolitinib. She remained RT-PCR positive for viral RNA for >120 days, and Pegylated interferon for 4 weeks led to viral RNA clearance. The observations support combination therapy of ruxolitinib + interferon for COVID-19.

Strong‐motion recordings of the 2014 Mw 8.2 Iquique and 2015 Mw 8.3 Illapel, Chile, earthquakes were analyzed to determine rupture propagation and the location, timing, and strength of subevents that produce most of the high‐frequency (≥1 Hz) ground motions. A moving window,cross‐correlation analysis of recordings from a local dense array, band‐pass filtered at 1 Hz, directly shows that the Iquique earthquake ruptured to the southeast over a distance of about 60 km. Array analysis of lower frequency energy (0.03–0.1 Hz) indicates that it occurred updip of the high‐frequency rupture. A methodology was developed for inverting the envelopes of acceleration records (1–5 Hz) to map high‐frequency source factors on the rupture zone and was applied to the two earthquakes. Waveforms of Mw 6 earthquakes were used as empirical Green’s functions in the inversions. High‐frequency subevents within the two Mw 8 earthquakes were located at depths ranging from 25 to 55 km and mostly occurred downdip of the peak slip of these earthquakes. Fourier spectral ratios of the Iquique mainshock with respect to Mw 5–6 aftershocks were fit to determine their stress drops. The stress drops were roughly constant from Mw 5 to 8 at 10–20 MPa. A compound rupture model is described in which subevents occur in areas of spatially heterogeneous strength and stress on the rupture, and produce the high‐frequency radiated energy of the overall earthquake, but are not located in the areas of peak slip. The stress drop of the overall earthquake is shown to equal the root mean square stress drop of subevents averaged over the rupture area.

Strong‐motion recordings of the 2014 Mw 8.2 Iquique and 2015 Mw 8.3 Illapel, Chile, earthquakes were analyzed to determine rupture propagation and the location, timing, and strength of subevents that produce most of the high‐frequency (≥1 Hz) ground motions. A moving window,cross‐correlation analysis of recordings from a local dense array, band‐pass filtered at 1 Hz, directly shows that the Iquique earthquake ruptured to the southeast over a distance of about 60 km. Array analysis of lower frequency energy (0.03–0.1 Hz) indicates that it occurred updip of the high‐frequency rupture. A methodology was developed for inverting the envelopes of acceleration records (1–5 Hz) to map high‐frequency source factors on the rupture zone and was applied to the two earthquakes. Waveforms of Mw 6 earthquakes were used as empirical Green’s functions in the inversions. High‐frequency subevents within the two Mw 8 earthquakes were located at depths ranging from 25 to 55 km and mostly occurred downdip of the peak slip of these earthquakes. Fourier spectral ratios of the Iquique mainshock with respect to Mw 5–6 aftershocks were fit to determine their stress drops. The stress drops were roughly constant from Mw 5 to 8 at 10–20 MPa. A compound rupture model is described in which subevents occur in areas of spatially heterogeneous strength and stress on the rupture, and produce the high‐frequency radiated energy of the overall earthquake, but are not located in the areas of peak slip. The stress drop of the overall earthquake is shown to equal the root mean square stress drop of subevents averaged over the rupture area.

An 83-year-old female had asymptomatic SARS-CoV-2 infection while taking ruxolitinib. She remained RT-PCR positive for viral RNA for >120 days, and Pegylated interferon for 4 weeks led to viral RNA clearance. The observations support combination therapy of ruxolitinib + interferon for COVID-19.

A 61-year-old male on everolimus had chronic SARS-CoV-2 infection. Addition of pegylated interferon cleared viral RNA and supports combination therapy with everolimus plus interferon for COVID-19.

An 83-year-old female had asymptomatic SARS-CoV-2 infection while taking ruxolitinib. She remained RT-PCR positive for viral RNA for >120 days, and Pegylated interferon for 4 weeks led to viral RNA clearance. The observations support combination therapy of ruxolitinib + interferon for COVID-19.

A 61-year-old male on everolimus had chronic SARS-CoV-2 infection. Addition of pegylated interferon cleared viral RNA and supports combination therapy with everolimus plus interferon for COVID-19.

The purpose of this study is to describe the clinical and prognostic features and to evaluate the outcome of different therapeutic approaches among patients with blastic plasmacytoid dendritic cell neoplasm (BPDCN) who have been diagnosed and treated in different institutions. A total of 398 patients from 75 centers were included in the study. Treatment consisted of non-Hodgkin lymphoma (NHL)-like regimens in 129 (32.8%) patients and acute leukemia (AL)-like regimens in 113 (23.5%) patients. In 61 (15.5%) and 16 (4.1%) patients, chemotherapy was followed by allogeneic and autologous hematopoietic stem cell transplantation (HSCT), respectively. Twenty-seven (6.9%) patients received radiotherapy, 6 (1.5%) received new agents, and 62 (15.7%) received palliative care. After a median follow-up of 12 months, median overall survival (OS) was 18 months. Patients who received NHL/AL-like regimens, followed by allogeneic HSCT, had the best outcome; median OS was not reached. OS was 65 months for patients who underwent autologous HSCT; 18 months and 14 months, respectively, for those treated with AL-like and NHL-like regimens without consolidation; and 4 months for those receiving palliative care (P < .001). In BPDCN, chemotherapy with lymphoma- or AL-like regimens, followed by transplantation, represents the therapeutic strategy associated with the best outcome. Consolidation with allogeneic HSCT, when feasible, appears superior to autologous HSCT

Every year more than 8 million people suffer from cancer-related deaths worldwide [1]. Metastasis, the spread of cancer to distant sites, accounts for 90% of these deaths. A promising target for blocking tumor progression, without causing severe side effects [2], is Tumor Endothelial Marker 8 (TEM8), an integrin-like cell surface protein expressed predominantly in the tumor endothelium and in cancer cells [3, 4]. Here, we have investigated the role of TEM8 in cancer progression, angiogenesis and metastasis in invasive breast cancer, and validated the main findings and important results in colorectal cancer. We show that the loss of TEM8 in cancer cells results in inhibition of cancer progression, reduction in tumor angiogenesis and reduced metastatic burden in breast cancer mouse models. Furthermore, we show that TEM8 regulates cancer progression by affecting the expression levels of cell cycle-related genes. Taken together, our findings may have broad clinical and therapeutic potential for breast and colorectal primary tumor and metastasis treatment by targeting TEM8.

Every year more than 8 million people suffer from cancer-related deaths worldwide [1]. Metastasis, the spread of cancer to distant sites, accounts for 90% of these deaths. A promising target for blocking tumor progression, without causing severe side effects [2], is Tumor Endothelial Marker 8 (TEM8), an integrin-like cell surface protein expressed predominantly in the tumor endothelium and in cancer cells [3, 4]. Here, we have investigated the role of TEM8 in cancer progression, angiogenesis and metastasis in invasive breast cancer, and validated the main findings and important results in colorectal cancer. We show that the loss of TEM8 in cancer cells results in inhibition of cancer progression, reduction in tumor angiogenesis and reduced metastatic burden in breast cancer mouse models. Furthermore, we show that TEM8 regulates cancer progression by affecting the expression levels of cell cycle-related genes. Taken together, our findings may have broad clinical and therapeutic potential for breast and colorectal primary tumor and metastasis treatment by targeting TEM8.

Native proaerolysin is a channel-forming bacterial protoxin that binds to cell-surface receptors and then is activated by furin or furin-like proteases. We genetically engineered proaerolysin by replacing the furin-cleavage sequence with a prostate-specific antigen-selective sequence. The recombinant modified proaerolysin was expressed and purified from Aeromonas salmonicida in good yields and purity. Recombinant modified proaerolysin had no furin sensitivity and markedly increased prostate-specific antigen sensitivity relative to wild-type proaerolysin. Human prostate cancer cells were significantly more sensitive to recombinant modified proaerolysin in the presence of active prostate-specific antigen when compared with the absence of prostate-specific antigen or the presence of potent prostate-specific antigen inhibitors. Most normal human cells with the exception of prostate and renal epithelial cells showed very low sensitivity to recombinant modified proaerolysin. Our results suggest that recombinant modified proaerolysin is a potent prostate-specific antigen-sensitive protoxin that deserves further development for regional therapy of benign and malignant prostate growths.

DT388GMCSF, a fusion toxin composed of the NH2-terminal region of diphtheria toxin (DT) fused to human granulocyte-macrophage colony-stimulating factor (GMCSF) has shown efficacy in the treatment of acute myeloid leukemia. However, the primary dose-limiting side effect is liver toxicity. We have reproduced liver toxicity in rats using the rodent cell-tropic DT-murine GMCSF (DT390mGMCSF). Serum aspartate aminotransferase and alanine aminotransferase were elevated 15- and 4-fold, respectively, in DT390mGMCSF-treated rats relative to controls. Histologic analysis revealed hepatocyte swelling; however, this did not lead to hepatic necrosis or overt histopathologic changes in the liver. Immunohistochemical staining showed apoptotic cells in the sinusoids, and depletion of cells expressing the monocyte/macrophage markers, ED1 and ED2, indicating that Kupffer cells (KC) are targets of DT390mGMCSF. In contrast, sinusoidal endothelial cells seemed intact. In vitro, DT390mGMCSF was directly cytotoxic to primary KC but not hepatocytes. Two related fusion toxins, DT388GMCSF, which targets the human GMCSF receptor, and DT390mIL-3, which targets the rodent IL-3 receptor, induced a less than 2-fold elevation in serum transaminases and did not deplete KC in vivo. In addition, DTU2mGMCSF, a modified form of DT390mGMCSF with enhanced tumor cell specificity, was not hepatotoxic and was significantly less toxic to KC in vivo and in vitro. These results show that DT390mGMCSF causes liver toxicity by targeting KC, and establish a model for studying how this leads to hepatocyte injury. Furthermore, alternative fusion toxins with potentially reduced hepatotoxicity are presented.

Anthrax lethal toxin, composed of protective antigen and lethal factor, was tested for cytotoxicity to human melanoma cell lines and normal human cells. Eleven of 18 melanoma cell lines were sensitive to anthrax lethal toxin (IC50 < 400 pmol/L) and 10 of these 11 sensitive cell lines carried the V599E BRAF mutation. Most normal cell types (10 of 15) were not sensitive to anthrax lethal toxin and only 5 of 15 normal human cell types were sensitive to anthrax lethal toxin (IC50 < 400 pmol/L). These cells included monocytes and a subset of endothelial cells. In both melanoma cell lines and normal cells, anthrax toxin receptor expression levels did not correlate with anthrax lethal toxin cytotoxicity. Furthermore, an anthrax toxin receptor–deficient cell line (PR230) did not show any enhanced sensitivity to anthrax lethal toxin when transfected with anthrax toxin receptor. Anthrax lethal toxin toxicity correlated with elevated phosphorylation levels of mitogen-activated protein/extracellular signal-regulated kinase kinase (MEK) 1/2 in both melanoma cell lines and normal cells. Anthrax lethal toxin–sensitive melanoma cell lines and normal cells had higher phospho-MEK1/2 levels than anthrax lethal toxin–resistant melanoma cell lines and normal tissue types. U0126, a specific MEK1/2 inhibitor, was not toxic to anthrax lethal toxin–resistant melanoma cell lines but was toxic to 8 of 11 anthrax lethal toxin–sensitive cell lines. These results show that anthrax lethal toxin toxicity correlates with elevated levels of active MEK1/2 pathway but not with anthrax toxin receptor expression levels in both normal and malignant tissues. Anthrax lethal toxin may be a useful therapeutic for melanoma patients, especially those carrying the V599E BRAF mutation with constitutive activation of the mitogen-activated protein kinase pathway.

Novel agents to treat acute myeloid leukemia (AML) are needed with increased efficacy and specificity. We have synthesized a dual-specificity fusion toxin DTU2GMCSF composed of the catalytic and translocation domains of diphtheria toxin (DT) fused to the granulocyte-macrophage colony-stimulating factor (GM-CSF) in which the DT furin cleavage site 163RVRRSV170 is modified to a urokinase plasminogen activator (uPA) cleavage site 163GSGRSA170, termed U2. DTU2GMCSF was highly toxic to the TF1-vRaf AML cell line (proliferation inhibition assay; IC50 = 3.14 pM), and this toxicity was greatly inhibited following pretreatment with anti-uPA and anti-GM-CSF antibodies. The activity of this toxin was then tested on a larger group of 13 human AML cell lines; 5 of the 13 cell lines were sensitive to DTU2GMCSF. An additional 5 of the 13 cell lines became sensitive when exogenous pro-uPA was added. Sensitivity to DTU2GMCSF strongly correlated with the expression levels of uPA receptors (uPARs) and GM-CSF receptors (GM-CSFRs) as well as with total uPA levels. DTU2GMCSF was less toxic to normal cells expressing uPAR or GMCSFR alone, that is, human umbilical vein endothelial cells and peripheral macrophages, respectively. These results indicate that DTU2GMCSF may be a selective and potent agent for the treatment of patients with AML. (Blood. 2004;104:2143-2148)

In this study, we attempt to target the mitogen-activated protein kinase (MAPK) pathway in acute myeloid leukemia (AML) cells using a recombinant anthrax lethal toxin (LeTx). LeTx consists of protective antigen (PrAg) and lethal factor (LF). PrAg binds cells, is cleaved by furin, oligomerizes, binds three to four molecules of LF, and undergoes endocytosis, releasing LF into the cytosol. LF cleaves MAPK kinases, inhibiting the MAPK pathway. We tested potency of LeTx on a panel of 11 human AML cell lines. Seven cell lines showed cytotoxic responses to LeTx. Cytotoxicity of LeTx was mimicked by the specific mitogen-activated protein/extracellular signal-regulated kinase kinase 1/2 (MEK1/2) inhibitor U0126, indicating that LeTx-induced cell death is mediated through the MEK1/2-extracellular signal-regulated kinase (ERK1/2) branch of the MAPK pathway. The four LeTx-resistant cell lines were sensitive to the phosphatidylinositol 3-kinase inhibitor LY294002. Co-treatment of AML cells with both LeTx and LY294002 did not lead to increased sensitivity, showing a lack of additive/synergistic effects when both pathways are inhibited. Flow cytometry analysis of MAPK pathway activation revealed the presence of phospho-ERK1/2 only in LeTx-sensitive cells. Staining for Annexin V/propidium iodide and active caspases showed an increase in double-positive cells and the absence of caspase activation following treatment, indicating that LeTx-induced cell death is caspase-independent and nonapoptotic. We have shown that a majority of AML cell lines are sensitive to the LF-mediated inhibition of the MAPK pathway. Furthermore, we have demonstrated that LeTx-induced cytotoxicity in AML cells is nonapoptotic and dependent on phospho-ERK1/2 levels.

In this study, we attempt to target Arginine auxotrophy in glioblastoma multiforme (GBM) cells using a pegylated recombinant human Arginase I cobalt [HuArgI (Co)-PEG5000]. We tested and characterized the activity of HuArgI (Co)-PEG5000 on a panel of 9 GBM cell lines and on human fetal glial cells (SVG-p12). HuArgI (Co)-PEG5000 was cytotoxic to all GBM cells tested. SVG-p12 cells were not sensitive demonstrating the selective cytotoxicity of HuArgI (Co)-PEG5000-induced arginine deprivation. Addition of l-citrulline led to the rescue of 6 GBM cell lines but only at concentrations of 11.4 mM, reflecting the extent of arginine auxotrophy in GBM. The ability of l-citrulline to rescue cells was dependent on the expression of argininosuccinate synthetase-1 (ASS1) with the cells that were not rescued by l-citrulline being negative for ASS1 expression. Knocking-down ASS1 reversed the ability of l-citrulline to rescue GBM cells, further illustrating the dependence of arginine auxotrophy on ASS1 expression. Inhibition of autophagy increased cell sensitivity to HuArgI (Co)-PEG5000 indicating that, following arginine deprivation, autophagy plays a protective role in GBM cells. Analysis of the type of cell death revealed a lack of AnnexinV staining and caspase activation in HuArgI (Co)-PEG5000-treated cells, indicating that arginine deprivation induces caspase-independent, non-apoptotic cell death in GBM. We have shown that GBM cells are auxotrophic for arginine and can be selectively targeted using HuArgI (Co)-PEG5000-induced arginine depletion, thus demonstrating that l-Arginine deprivation is a potent and selective potential treatment for GBM.

In this study, we target arginine auxotrophy of AML cell lines using human arginase I cobalt-PEG5000. HuArgI(Co)-PEG5000 was cytotoxic to all AML cell lines tested. Mononuclear cells and CD34+ blasts were not sensitive demonstrating the selectivity of HuArgI(Co)-PEG5000-induced arginine deprivation. Addition of l-citrulline led to the rescue of five cell lines. The four cell lines that were not rescued by l-citrulline did not express argininosuccinate synthetase-1, indicating complete arginine auxotrophy. Inhibition of autophagy increased cell sensitivity to HuArgI(Co)-PEG5000 demonstrating the protective role of autophagy following arginine deprivation. We have shown that AML can be selectively targeted using HuArgI(Co)-PEG5000-induced arginine depletion.

Arthur E Frankel Department of Internal Medicine, Simmons Comprehensive Cancer Center, The University of Texas Southwestern Medical Center, Dallas, TX, USA Until recent decades, the role of the immune system in harnessing tumor growth was based on anecdotal observations of increased cancers in immune-compromised patients, the benefits of graft-versus-leukemia in allogeneic stem cell transplants, and the limited but reproducible anticancer activity of several lymphokines, including interferon and interleukin (IL)-2. Vaccine studies and infusions of "activated" lymphocytes yielded variable clinical responses and disease control. An improved understanding of the molecular and cell mechanisms of the innate and adaptive immune system in cancer-bearing animals and the discovery of an immune-suppressive tumor microenvironment then led to development and testing of a battery of new drug and cell-based approaches to trigger antitumor immunity. This issue of Clinical Pharmacology: Advances and Applications highlights some of the new protein-based compounds that are radically changing the cancer therapeutic landscape. The purpose of this collection of reviews is to inform the readership regarding the importance of the seismic change in cancer therapeutics and stimulate efforts to find novel niches and combinations of agents similar to recent advances in the application of cancer pathway inhibitors.

Arthur E Frankel Department of Internal Medicine, Simmons Comprehensive Cancer Center, The University of Texas Southwestern Medical Center, Dallas, TX, USA Until recent decades, the role of the immune system in harnessing tumor growth was based on anecdotal observations of increased cancers in immune-compromised patients, the benefits of graft-versus-leukemia in allogeneic stem cell transplants, and the limited but reproducible anticancer activity of several lymphokines, including interferon and interleukin (IL)-2. Vaccine studies and infusions of "activated" lymphocytes yielded variable clinical responses and disease control. An improved understanding of the molecular and cell mechanisms of the innate and adaptive immune system in cancer-bearing animals and the discovery of an immune-suppressive tumor microenvironment then led to development and testing of a battery of new drug and cell-based approaches to trigger antitumor immunity. This issue of Clinical Pharmacology: Advances and Applications highlights some of the new protein-based compounds that are radically changing the cancer therapeutic landscape. The purpose of this collection of reviews is to inform the readership regarding the importance of the seismic change in cancer therapeutics and stimulate efforts to find novel niches and combinations of agents similar to recent advances in the application of cancer pathway inhibitors.

Jung-Ki Yoon,1,2 Arthur E Frankel,3 Lynn G Feun,4 Suhendan Ekmekcioglu,1 Kevin B Kim11Department of Melanoma Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; 2Hwasung Public Health Center, Hwasung, South Korea, 3Scott and White Cancer Research Institute, Temple, TX, USA; 4Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USAAbstract: Despite recent development of promising immunotherapeutic and targeted drugs, prognosis in patients with advanced melanoma remains poor, and a cure for this disease remains elusive in most patients. The success of melanoma therapy depends on a better understanding of the biology of melanoma and development of drugs that effectively target the relevant genes or proteins essential for tumor cell survival. Melanoma cells frequently lack argininosuccinate synthetase, an essential enzyme for arginine synthesis, and as a result they become dependent on the availability of exogenous arginine. Accordingly, a therapeutic approach involving depletion of available arginine has been shown to be effective in preclinical studies. Early clinical studies have demonstrated sufficient antitumor activity to give rise to cautious optimism. In this article, the rationale for arginine deprivation therapy is discussed. Additionally, various strategies for depleting arginine are discussed and the preclinical and clinical investigations of arginine deprivation therapy in melanoma are reviewed.Keywords: arginine deprivation, argininosuccinate synthetase, melanoma

Jung-Ki Yoon,1,2 Arthur E Frankel,3 Lynn G Feun,4 Suhendan Ekmekcioglu,1 Kevin B Kim11Department of Melanoma Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA; 2Hwasung Public Health Center, Hwasung, South Korea, 3Scott and White Cancer Research Institute, Temple, TX, USA; 4Sylvester Comprehensive Cancer Center, University of Miami Miller School of Medicine, Miami, FL, USAAbstract: Despite recent development of promising immunotherapeutic and targeted drugs, prognosis in patients with advanced melanoma remains poor, and a cure for this disease remains elusive in most patients. The success of melanoma therapy depends on a better understanding of the biology of melanoma and development of drugs that effectively target the relevant genes or proteins essential for tumor cell survival. Melanoma cells frequently lack argininosuccinate synthetase, an essential enzyme for arginine synthesis, and as a result they become dependent on the availability of exogenous arginine. Accordingly, a therapeutic approach involving depletion of available arginine has been shown to be effective in preclinical studies. Early clinical studies have demonstrated sufficient antitumor activity to give rise to cautious optimism. In this article, the rationale for arginine deprivation therapy is discussed. Additionally, various strategies for depleting arginine are discussed and the preclinical and clinical investigations of arginine deprivation therapy in melanoma are reviewed.Keywords: arginine deprivation, argininosuccinate synthetase, melanoma

Arthur E FrankelScott and White Cancer ResearchInstitute, Temple, TX, USAClinical Pharmacology: Advances and Applications is now in its second year. The turnaround time for the publishing of manuscripts is a few weeks. Peer reviews are high quality, and the journal is open access, filling an important niche in academic medical publishing.Specifically, the journal was designed to bridge the gap between basic science and clinical practice. Because of the explosion in the market of new drugs and biomarkers secondary to in silico drug design, high-throughput screens, large cooperative group clinical trials, and patient characterizations by genomic and proteomic analyses, we now have a huge amount of information on drug targets and host responses. Although such a plethora of knowledge should promise rapid advances, in fact in many cases it has led to a partial paralysis of action both by pharmacologists and by physicians. How do we make sense of this massive complexity? Will any action we take be seen as erroneous in weeks or months?

Arthur E FrankelScott and White Cancer ResearchInstitute, Temple, TX, USAClinical Pharmacology: Advances and Applications is now in its second year. The turnaround time for the publishing of manuscripts is a few weeks. Peer reviews are high quality, and the journal is open access, filling an important niche in academic medical publishing.Specifically, the journal was designed to bridge the gap between basic science and clinical practice. Because of the explosion in the market of new drugs and biomarkers secondary to in silico drug design, high-throughput screens, large cooperative group clinical trials, and patient characterizations by genomic and proteomic analyses, we now have a huge amount of information on drug targets and host responses. Although such a plethora of knowledge should promise rapid advances, in fact in many cases it has led to a partial paralysis of action both by pharmacologists and by physicians. How do we make sense of this massive complexity? Will any action we take be seen as erroneous in weeks or months?