Reverting the molecular fingerprint of tumor dormancy as a therapeutic strategy for glioblastoma.

Glioblastoma is an aggressive and invasive brain malignancy with high mortality rates despite current treatment modalities. In this study, we show that a 7-gene signature, previously found to govern the switch of glioblastomas from dormancy to aggressive tumor growth, correlates with improved overall survival of patients with glioblastoma. Using glioblastoma dormancy models, we validated the role of 2 genes from the signature, thrombospondin-1 ( TSP-1) and epidermal growth factor receptor ( EGFR), as regulators of glioblastoma dormancy and explored their therapeutic potential. EGFR up-regulation was reversed using EGFR small interfering RNA polyplex, antibody, or small-molecule inhibitor. The diminished function of TSP-1 was augmented via a peptidomimetic. The combination of EGFR inhibition and TSP-1 restoration led to enhanced therapeutic efficacy in vitro, in 3-dimensional patient-derived spheroids, and in a subcutaneous human glioblastoma model in vivo. Systemic administration of the combination therapy to mice bearing intracranial murine glioblastoma resulted in marginal therapeutic outcomes, probably due to brain delivery challenges, p53 mutation status, and the aggressive nature of the selected cell line. Nevertheless, this study provides a proof of concept for exploiting regulators of tumor dormancy for glioblastoma therapy. This therapeutic strategy can be exploited for future investigations using a variety of therapeutic entities that manipulate the expression of dormancy-associated genes in glioblastoma as well as in other cancer types.-Tiram, G., Ferber, S., Ofek, P., Eldar-Boock, A., Ben-Shushan, D., Yeini, E., Krivitsky, A., Blatt, R., Almog, N., Henkin, J., Amsalem, O., Yavin, E., Cohen, G., Lazarovici, P., Lee, J. S., Ruppin, E., Milyavsky, M., Grossman, R., Ram, Z., Calderón, M., Haag, R., Satchi-Fainaro, R. Reverting the molecular fingerprint of tumor dormancy as a therapeutic strategy for glioblastoma.

Major hurdles to the use of tyrosine kinase inhibitors in clinical prevention/interception studies: Do preclinical studies with EGFR inhibitors suggest approaches to overcome some of the limitations.

There are major hurdles to the use of tyrosine kinase inhibitors (TKIs) and any other agents with significant toxicities (which means practically the preponderance of potential effective agents) in the context of prevention/anti-progression (interception) studies. We will discuss epidermal growth factor receptor (EGFR) inhibitors as examples, both in a primary prevention setting, where agent(s) are administered to individuals with no cancer but who might be considered at higher risk due to a variety of factors, and in anti-progression/interception studies, where agent(s) are administered to persons with known preinvasive lesions (e.g., colon adenomas, lung nodules, ductal carcinoma in situ (DCIS), or pancreatic intraepithelial neoplasia (PanIN) lesions in the pancreas) in an attempt to reverse or inhibit progression of these lesions. Multiple potential hurdles will be examined, including: a) toxicity of agents, b) the likely range of subtypes of cancers affected by a given treatment (e.g., EGFR inhibitors against EGFR mutant lung adenocarcinomas), c) the availability of practical endpoints besides the blocking of cancer formation or pharmacokinetics related to the agents administered in a primary prevention study, and d) the interpretation of the regression or blockage of new preinvasive lesions in the anti-progression study. Such an anti-progression approach may help address some of the factors commented on regarding primary prevention (toxicity, potential target organ cancer subtypes) but still leaves major questions regarding interpretation of modulation of preinvasive endpoints when it may not be clear how frequently they progress to clinical cancer. Additionally, we address whether certain recent preclinical findings might be able to reduce the toxicities associated with these agents and perhaps even increase their potential efficacy. Antibodies and TKIs other than the EGFR inhibitors are not discussed because few if any had been tested as monotherapies in humans, making their efficacy harder to predict, and because a number have relatively rare but quite striking toxicities. Furthermore, most of the practical hurdles raised regarding the EGFR inhibitors are relevant to the other TKIs. Finally, we briefly discuss whether early detection employing blood or serum samples may allow identification of high-risk groups more amenable to agents with greater toxicity.

Kinase Inhibitors as Potential Therapeutic Agents in the Treatment of COVID-19.

Corona virus is quickly spreading around the world. The goal of viral management is to disrupt the virus's life cycle, minimize lung damage, and alleviate severe symptoms. Numerous strategies have been used, including repurposing existing antivirals or drugs used in previous viral outbreaks. One such strategy is to repurpose FDA-approved kinase inhibitors that are potential chemotherapeutic agents and have demonstrated antiviral activity against a variety of viruses, including MERS, SARS-CoV-1, and others, by inhibiting the viral life cycle and the inflammatory response associated with COVID-19. The purpose of this article is to identify licensed kinase inhibitors that have the ability to reduce the virus's life cycle, from entrance through viral propagation from cell to cell. Several of these inhibitors, including imatinib, ruxolitinib, silmitasertib, and tofacitinib (alone and in conjunction with hydroxychloroquine), are now undergoing clinical studies to determine their efficacy as a possible treatment drug. The FDA approved baricitinib (a Janus kinase inhibitor) in combination with remdesivir for the treatment of COVID-19 patients receiving hospital care in November 2020. While in vitro trials with gilteritinib, fedratinib, and osimertinib are encouraging, further research is necessary before these inhibitors may be used to treat COVID-19 patients.