The Egr transcription factor family: From signal transduction to kidney differentiation

Extracellular “signals” in the form of neurotransmitters, growth factors, hormones, and matrix are known to be key modulators of cellular phenotype. These agents lead to the generation of second messenger signals in the plasma membrane and cytosol. In turn, these biochemical events modulate the expression of a set of so-called immediate-early genes (IEG), whose induction does not require de novo protein synthesis. Several years ago, we and others identified several IEGs [reviewed in 1 and 2]. Of particular interest to our laboratory has been a subset of IEGs that encode transcription factors, since as such they might: (1) be the targets for second messenger events, and (2) activate or repress the transcription of critical genes required to effect a particular cellular phenotype. Thus, immediate-early transcription factors (IETF) should couple short-term responses in the form of second messenger events to long-term changes in gene expression instrumental in altering phenotype

The Repurposing Drugs in Oncology (ReDO) Project

The Repurposing Drugs in Oncology (ReDO) Project seeks to repurpose well-known and well-characterised non-cancer drugs for new uses in oncology. The rationale for this project is presented, examining current issues in oncological drug development, challenges for health systems, and existing and future patient needs. In addition to discussing the advantages of repurposing, the paper also outlines some of the characteristics used in the selection of drug candidates by this project. Challenges in moving candidate drugs into clinical trial and subsequent practice are also discussed

Repurposing drugs in oncology (ReDO)—cimetidine as an anti-cancer agent

Cimetidine, the first H2 receptor antagonist in widespread clinical use, has anti-cancer properties that have been elucidated in a broad range of pre-clinical and clinical studies for a number of different cancer types. These data are summarised and discussed in relation to a number of distinct mechanisms of action. Based on the evidence presented, it is proposed that cimetidine would synergise with a range of other drugs, including existing chemotherapeutics, and that further exploration of the potential of cimetidine as an anti-cancer therapeutic is warranted. Furthermore, there is compelling evidence that cimetidine administration during the peri-operative period may provide a survival benefit in some cancers. A number of possible combinations with other drugs are discussed in the supplementary material accompanying this paper

Repurposing Drugs in Oncology (ReDO)—mebendazole as an anti-cancer agent

Mebendazole, a well-known anti-helminthic drug in wide clinical use, has anti-cancer properties that have been elucidated in a broad range of pre-clinical studies across a number of different cancer types. Significantly, there are also two case reports of anti-cancer activity in humans. The data are summarised and discussed in relation to suggested mechanisms of action. Based on the evidence presented, it is proposed that mebendazole would synergise with a range of other drugs, including existing chemotherapeutics, and that further exploration of the potential of mebendazole as an anti-cancer therapeutic is warranted. A number of possible combinations with other drugs are discussed in the Appendix

Tumor-derived lactate and myeloid-derived suppressor cells: Linking metabolism to cancer immunology

Many malignant cells produce increased amounts of lactate, which promotes the development of myeloid-derived suppressor cells (MDSCs). MDSCs, lactate, and a low pH in the tumor microenvironment inhibit the function of natural killer (NK) cells and T lymphocytes, hence allowing for disease progression. Ketogenic diets can deplete tumor-bearing animals from MDSCs and regulatory T cells, thereby improving their immunological profile

Fluvoxamine: A review of its mechanism of action and its role in COVID-19

Fluvoxamine is a well-tolerated, widely available, inexpensive selective serotonin reuptake inhibitor that has been shown in a small, double-blind, placebo-controlled, randomized study to prevent clinical deterioration of patients with mild coronavirus disease 2019 (COVID-19). Fluvoxamine is also an agonist for the sigma-1 receptor, through which it controls inflammation. We review here a body of literature that shows important mechanisms of action of fluvoxamine and other SSRIs that could play a role in COVID-19 treatment. These effects include: reduction in platelet aggregation, decreased mast cell degranulation, interference with endolysosomal viral trafficking, regulation of inositol-requiring enzyme 1α-driven inflammation and increased melatonin levels, which collectively have a direct antiviral effect, regulate coagulopathy or mitigate cytokine storm, which are known hallmarks of severe COVID-19

Readily available drugs and other interventions to potentially improve the efficacy of immune checkpoint blockade in cancer

To improve the efficacy of immune checkpoint inhibitors (ICIs) for cancer treatment, various strategies, including combination therapies with repurposed drugs, are being explored. Several readily available interventions with potential to enhance programmed death 1 (PD-1) blockade have been identified. However, these interventions often remain overlooked due to the lack of financial incentives for their development, making them financial orphans. This review summarizes current knowledge regarding off-label drugs, supplements, and other readily available interventions that could improve the efficacy of PD-1 blockade. The summary of each intervention includes the proposed mechanism of action for combination with checkpoint inhibitors and data from animal and human studies. Additionally, we include summaries of common interventions to be avoided by patients on PD-1 blockade. Finally, we present approaches for conducting further studies in patients, with the aim of expediting the clinical development of these interventions. We strive to increase awareness of readily available combination therapies that may advance cancer immunotherapy and help patients today

Repurposing Drugs in Oncology (ReDO)—nitroglycerin as an anti-cancer agent

Nitroglycerin (NTG), a drug that has been in clinical use for more than a century, has a range of actions which make it of particular interest in an oncological setting. It is generally accepted that the main mechanism of action of NTG is via the production of nitric oxide (NO), which improves cardiac oxygenation via multiple mechanisms including improved blood flow (vasodilation), decreased platelet aggregation, increased erythrocyte O2 release and decreased mitochondrial utilization of oxygen. Its vasoactive properties mean that it has the potential to exploit more fully the enhanced permeability and retention effect in delivering anti-cancer drugs to tumour tissues. Moreover NTG can reduce HIF-1α levels in hypoxic tumour tissues and this may have anti-angiogenic, pro-apoptotic and anti-efflux effects. Additionally NTG may enhance anti-tumour immunity. Pre-clinical and clinical data on these anti-cancer properties of NTG are summarised and discussed. While there is evidence of a positive action as a monotherapy in prostate cancer, there are mixed results in NSCLC where initially positive results have yet to be fully replicated. Based on the evidence presented, a case is made that further exploration of the clinical benefits that may accrue to cancer patients is warranted. Additionally, it is proposed that NTG may synergise with a number of other drugs, including other repurposed drugs, and these are discussed in the supplementary material appended to this paper

A Case of Complete and Durable Molecular Remission of Chronic Lymphocytic Leukemia Following Treatment with Epigallocatechin-3-gallate, an Extract of Green Tea

We report the case of a 48-year-old man who achieved a complete molecular remission 20 years after a diagnosis of chronic lymphocytic leukemia while using epigallicatechin-3-gallate, an extract of green tea. The patient presented at age 28 with lymphocytosis, mild anemia, mild thrombocytopenia, and massive splenomegaly, for which a splenectomy was performed. He was then followed expectantly. Over the next two decades, he suffered two symptomatic chronic lymphocytic leukemia-related events. The first occurred twelve years after diagnosis (at age 40) when the patient developed fevers, night sweats, and moderate anemia. He was diagnosed with autoimmune hemolytic anemia secondary to chronic lymphocytic leukemia. The patient declined conventional therapy in favor of a diet, exercise, and supplement regimen, and recovered from the autoimmune hemolytic anemia though the underlying chronic lymphocytic leukemia remained evident. This is the first published case report of "spontaneous" recovery from secondary autoimmune hemolytic anemia in an adult. Over the second decade following chronic lymphocytic leukemia diagnosis, serial bone marrow biopsies demonstrated increasing lymphocytosis, with minimal peripheral lymphocytosis. However, twenty years after diagnosis, peripheral lymphocytosis accelerated, with white blood cell counts rising to 55,000/µL. Because the patient continued to refuse conventional therapy, he was treated instead with a supplement regimen that included high doses of epigallocatechin-3-gallate, a green tea extract. Peripheral lymphocytosis resolved. More remarkably, a bone marrow examination, including flow cytometry, showed no evidence of a malignant clone. Two years later (at age 51), the peripheral blood and bone marrow were without molecular evidence of chronic lymphocytic leukemia or any malignancy. The patient remains well at age 52