Soluble Guanylate Cyclase ß1 Subunit Represses Human Glioblastoma Growth.

Malignant glioma is the most common and deadly brain tumor. A marked reduction in the levels of sGC (soluble guanylyl cyclase) transcript in the human glioma specimens has been revealed in our previous studies. In the present study, restoring the expression of sGCß1 alone repressed the aggressive course of glioma. The antitumor effect of sGCß1 was not associated with enzymatic activity of sGC since overexpression of sGCß1 alone did not influence the level of cyclic GMP. Additionally, sGCß1-induced inhibition of the growth of glioma cells was not influenced by treatment with sGC stimulators or inhibitors. The present study is the first to reveal that sGCß1 migrated into the nucleus and interacted with the promoter of the TP53 gene. Transcriptional responses induced by sGCß1 caused the G0 cell cycle arrest of glioblastoma cells and inhibition of tumor aggressiveness. sGCß1 overexpression impacted signaling in glioblastoma multiforme, including the promotion of nuclear accumulation of p53, a marked reduction in CDK6, and a significant decrease in integrin α6. These anticancer targets of sGCß1 may represent clinically important regulatory pathways that contribute to the development of a therapeutic strategy for cancer treatment.

Nitric oxide-releasing gel accelerates healing in a diabetic murine splinted excisional wound model.

Introduction: According to the American Diabetes Association (ADA), 9-12 million patients suffer from chronic ulceration each year, costing the healthcare system over USD $25 billion annually. There is a significant unmet need for new and efficacious therapies to accelerate closure of non-healing wounds. Nitric Oxide (NO) levels typically increase rapidly after skin injury in the inflammatory phase and gradually diminish as wound healing progresses. The effect of increased NO concentration on promoting re-epithelization and wound closure has yet to be described in the context of diabetic wound healing. Methods: In this study, we investigated the effects of local administration of an NO-releasing gel on excisional wound healing in diabetic mice. The excisional wounds of each mouse received either NO-releasing gel or a control phosphate-buffered saline (PBS)-releasing gel treatment twice daily until complete wound closure. Results: Topical administration of NO-gel significantly accelerated the rate of wound healing as compared with PBS-gel-treated mice during the later stages of healing. The treatment also promoted a more regenerative ECM architecture resulting in shorter, less dense, and more randomly aligned collagen fibers within the healed scars, similar to that of unwounded skin. Wound healing promoting factors fibronectin, TGF-ß1, CD31, and VEGF were significantly elevated in NO vs. PBS-gel-treated wounds. Discussion: The results of this work may have important clinical implications for the management of patients with non-healing wounds.

John Mendelsohn: A visionary scientist, oncologist and leader.

Dr. John Mendelsohn is credited for the concept of targeting the epidermal growth factor receptor (EGFR), providing the first evidence of anticancer activity of antagonist anti-EGFR mAb, and developing the Erbitux (Cetuximab) drug for cancer patients. During his professional journey, Dr. Mendelsohn also helped to build and elevate the status of three cancer cancers, all while touching the lives of cancer patients around the globe. He was a towering figure, and his passing in January 2019 casts a very long shadow over the entire field of cancer research and treatment. Although no one person can ever adequately fill John Mendelsohn's very large shoes, we can all learn by his remarkable example. Here we discuss Dr. Mendelsohn's professional life to spotlight his influence on oncology and also share personal reflections from us and several colleagues: Tony Hunter, Robert A. Weinberg, Robert C. Bast, Raymond Sawaya, David M. Gershenson, Christopher J Logothetis, Stanley R. Hamilton, Mien-Chie Hung, and George M. Stancel. See related article Kumar et al. Can Res 2019; 79:4315-4323.

Differentiation of Human Induced Pluripotent or Embryonic Stem Cells Decreases the DNA Damage Repair by Homologous Recombination.

The nitric oxide (NO)-cyclic GMP pathway contributes to human stem cell differentiation, but NO free radical production can also damage DNA, necessitating a robust DNA damage response (DDR) to ensure cell survival. How the DDR is affected by differentiation is unclear. Differentiation of stem cells, either inducible pluripotent or embryonic derived, increased residual DNA damage as determined by γ-H2AX and 53BP1 foci, with increased S-phase-specific chromosomal aberration after exposure to DNA-damaging agents, suggesting reduced homologous recombination (HR) repair as supported by the observation of decreased HR-related repair factor foci formation (RAD51 and BRCA1). Differentiated cells also had relatively increased fork stalling and R-loop formation after DNA replication stress. Treatment with NO donor (NOC-18), which causes stem cell differentiation has no effect on double-strand break (DSB) repair by non-homologous end-joining but reduced DSB repair by HR. Present studies suggest that DNA repair by HR is impaired in differentiated cells.

Tadalafil: Protective Action against the Development of Multiple Organ Failure Syndrome.

INTRODUCTION: Multiple organ failure syndrome (MOFS) is a pathology associated to unspecified and severe trauma, characterized by elevated morbidity and mortality. The complex inflammatory MOFS-related reactions generate important ischemia-reperfusion responses in the induction of this syndrome. Nitric oxide elevation, through the activation of cyclic guanosine monophosphate (cGMP), has the potential of counteracting the typical systemic vasoconstriction, and platelet-induced hypercoagulation. Tadalafil would possibly act protectively by reducing cGMP degradation with consequent diffuse vasodilatation, besides reduction of platelet-induced hypercoagulation, thus, preventing multiple organ failure syndrome development. METHODS: The experimental protocol was previously approved by an institution animal research committee. Experimental MOFS was induced through the stereotaxic micro-neurosurgical bilateral anterior hypothalamic lesions model. Groups of 10 Wistar rats were divided into: a) Non-operated control; b) Operated control group; c) 2 hours after tadalafil-treated operated group; d) 4 hours after tadalafil-treated operated group; e) 8 hours after post-treated operated group. The animals were sacrificed 24 hours after the neurosurgical procedure and submitted to histopathologic examination of five organs: brain, lungs, stomach, kidneys, and liver. RESULTS: The electrolytic hypothalamic lesions resulted in a full picture of MOFS with disseminated multiple-organs lesions, provoked primarily by diffusely spread micro-thrombi. The treatment with tadalafil 2 hours after the micro-neurosurgical lesions reduced the experimental MOFS lesions development, in a highly significant level (P<0.01) of 58.75%. The treatment with tadalafil, 4 hours after the micro-neurosurgically-induced MOFS lesions, also reduced in 49.71%, in a highly significant level (P<0.01). Finally, the treatment with tadalafil 8 hours after the neurosurgical procedure resulted in a statistically significant reduction of 30.50% (P<0.05) of the experimentally-induced MOFS gravity scores. CONCLUSION: The phosphodiesterase 5 inhibitor, tadalafil, in the doses and timing utilized, showed to protect against the experimentally-induced MOFS.

Tadalafil: protective action against the development of multiple organ failure syndrome

Abstract Introduction: Multiple organ failure syndrome (MOFS) is a pathology associated to unspecified and severe trauma, characterized by elevated morbidity and mortality. The complex inflammatory MOFS-related reactions generate important ischemia-reperfusion responses in the induction of this syndrome. Nitric oxide elevation, through the activation of cyclic guanosine monophosphate (cGMP), has the potential of counteracting the typical systemic vasoconstriction, and platelet-induced hypercoagulation. Tadalafil would possibly act protectively by reducing cGMP degradation with consequent diffuse vasodilatation, besides reduction of platelet-induced hypercoagulation, thus, preventing multiple organ failure syndrome development. Methods: The experimental protocol was previously approved by an institution animal research committee. Experimental MOFS was induced through the stereotaxic micro-neurosurgical bilateral anterior hypothalamic lesions model. Groups of 10 Wistar rats were divided into: a) Non-operated control; b) Operated control group; c) 2 hours after tadalafil-treated operated group; d) 4 hours after tadalafil-treated operated group; e) 8 hours after post-treated operated group. The animals were sacrificed 24 hours after the neurosurgical procedure and submitted to histopathologic examination of five organs: brain, lungs, stomach, kidneys, and liver. Results: The electrolytic hypothalamic lesions resulted in a full picture of MOFS with disseminated multiple-organs lesions, provoked primarily by diffusely spread micro-thrombi. The treatment with tadalafil 2 hours after the micro-neurosurgical lesions reduced the experimental MOFS lesions development, in a highly significant level (P<0.01) of 58.75%. The treatment with tadalafil, 4 hours after the micro-neurosurgically-induced MOFS lesions, also reduced in 49.71%, in a highly significant level (P<0.01). Finally, the treatment with tadalafil 8 hours after the neurosurgical procedure resulted in a statistically significant reduction of 30.50% (P<0.05) of the experimentally-induced MOFS gravity scores. Conclusion: The phosphodiesterase 5 inhibitor, tadalafil, in the doses and timing utilized, showed to protect against the experimentally-induced MOFS.

Enhancing cold atmospheric plasma treatment of cancer cells by static magnetic field.

It has been reported since late 1970 that magnetic field interacts strongly with biological systems. Cold atmospheric plasma (CAP) has also been widely studied over the past few decades in physics, biology, and medicine. In this study, we propose a novel idea to combine static magnetic field (SMF) with CAP as a tool for cancer therapy. Breast cancer cells and wild type fibroblasts were cultured in 96-well plates and treated by CAP with or without SMF. Breast cancer cells MDA-MB-231 showed a significant decrease in viability after direct plasma treatment with SMF (compared to only plasma treatment). In addition, cancer cells treated by the CAP-SMF-activated medium (indirect treatment) also showed viability decrease but was slightly weaker than the direct plasma-SMF treatment. By integrating the use of SMF and CAP, we were able to discover their advantages that have yet to be utilized. Bioelectromagnetics. 38:53-62, 2017. © 2016 Wiley Periodicals, Inc.

Epigenetic regulation of soluble guanylate cyclase (sGC) ß1 in breast cancer cells.

Soluble guanylate cyclase (sGC) is a heterodimer composed of α and ß subunits. The loss of sGCß1 has been implicated in several vascular and nonvascular diseases. Our analysis showed that higher levels of sGCß1 in breast cancer tissues are correlated with greater survival probability than lower sGCß1 levels. However, there is no information on sGC regulation by epigenetic mechanisms. We examined the role of histone deacetylase (HDAC) inhibitors in regulating sGCα1 and -ß1 expression in human breast cancer MDA-MB-231 and MDA-MB-468 cell lines. The class I HDAC inhibitors increased the expression of sGCß1 more than sGCα1. Transient overexpression of HDAC3, but not HDAC1 or HDAC2, significantly reduced sGCß1 mRNA. Chromatin immunoprecipitation assay confirmed an enhanced binding of HDAC3 to the sGCß1 proximal promoter, which could be reversed by panobinostat (LBH-589) treatment. Mutations at the CCAAT binding sequence, a major element regulating sGCß1 expression, markedly reduced the efficacy of LBH-589 in augmenting sGCß1 promoter activity. LBH-589 markedly enhanced the binding of nuclear transcription factor Y, subunit α, to the sGCß1 promoter (CCAAT binding sequence). In summary, HDAC3 is an endogenous antagonist of sGCß1 expression. Inhibition of HDAC3 with targeted therapy could benefit treatment of the diseases associated with sGCß1 down-regulation and/or deficiency such as cancer and several vascular-related diseases.-Sotolongo, A., Mónica, F. Z., Kots, A., Xiao, H., Liu, J., Seto, E., Bian, K., Murad, F. Epigenetic regulation of soluble guanylate cyclase (sGC) ß1 in breast cancer cells.

Stabilizing the cold plasma-stimulated medium by regulating medium's composition.

Over past several years, the cold plasma-stimulated medium (PSM) has shown its remarkable anti-cancer capacity in par with the direct cold plasma irradiation on cancer cells or tumor tissues. Independent of the cold plasma device, PSM has noticeable advantage of being a flexible platform in cancer treatment. Currently, the largest disadvantage of PSM is its degradation during the storage over a wide temperature range. So far, to stabilize PSM, it must be remained frozen at -80 °C. In this study, we first reveal that the degradation of PSM is mainly due to the reaction between the reactive species and specific amino acids; mainly cysteine and methionine in medium. Based on this finding, both H2O2 in PSM and the anti-cancer capacity of PSM can be significantly stabilized during the storage at 8 °C and -25 °C for at least 3 days by using phosphate-buffered saline (PBS) and cysteine/methionine-free Dulbecco's Modified Eagle Medium (DMEM). In addition, we demonstrate that adding a tyrosine derivative, 3-Nitro-L-tyrosine, into DMEM can mitigate the degradation of PSM at 8 °C during 3 days of storage. This study provides a solid foundation for the future anti-cancer application of PSM.