Design and synthesis of an in vivo-efficacious PIM3 kinase inhibitor as a candidate anti-pancreatic cancer agent

PIM3 Kinase: A Promising Novel Target in Solid Cancers

PIM3 (provirus-integrating Moloney site 3) is a serine/threonine kinase and belongs to the PIM family (PIM1, PIM2, and PIM3). PIM3 is a proto-oncogene that is frequently overexpressed in cancers originating from endoderm-derived tissues, such as the liver, pancreas, colon, stomach, prostate, and breast cancer. PIM3 plays a critical role in activating multiple oncogenic signaling pathways promoting cancer cell proliferation, survival, invasion, tumor growth, metastasis, and progression, as well as chemo- and radiation therapy resistance and immunosuppressive microenvironment. Genetic inhibition of PIM3 expression suppresses in vitro cell proliferation and in vivo tumor growth and metastasis in mice with solid cancers, indicating that PIM3 is a potential therapeutic target. Although several pan-PIM inhibitors entered phase I clinical trials in hematological cancers, there are currently no FDA-approved inhibitors for the treatment of patients. This review provides an overview of recent developments and insights into the role of PIM3 in various cancers and its potential as a novel molecular target for cancer therapy. We also discuss the current status of PIM-targeted therapies in clinical trials.

Corynoline inhibits esophageal squamous cell carcinoma growth via targeting Pim-3

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is an aggressive and deadly malignancy characterized by late-stage diagnosis, therapy resistance, and a poor 5-year survival rate. Finding novel therapeutic targets and their inhibitors for ESCC prevention and therapy is urgently needed.

METHODS

We investigated the proviral integration site for maloney murine leukemia virus 3 (Pim-3) protein levels using immunohistochemistry. Using Methyl Thiazolyl Tetrazolium and clone formation assay, we verified the function of Pim-3 in cell proliferation. The binding and inhibition of Pim-3 by corynoline were verified by computer docking, pull-down assay, cellular thermal shift assay, and kinase assay. Cell proliferation, Western blot, and a patient-derived xenograft tumor model were performed to elucidate the mechanism of corynoline inhibiting ESCC growth.

RESULTS

Pim-3 was highly expressed in ESCC and played an oncogenic role. The augmentation of Pim-3 enhanced cell proliferation and tumor development by phosphorylating mitogen-activated protein kinase 1 (MAPK1) at T185 and Y187. The deletion of Pim-3 induced apoptosis with upregulated cleaved caspase-9 and lower Bcl2 associated agonist of cell death (BAD) phosphorylation at S112. Additionally, binding assays demonstrated corynoline directly bound with Pim-3, inhibiting its activity, and suppressing ESCC growth.

CONCLUSIONS

Our findings suggest that Pim-3 promotes ESCC progression. Corynoline inhibits ESCC progression through targeting Pim-3.

Bioactive Aurones, Indanones, and Other Hemiindigoid Scaffolds: Medicinal Chemistry and Photopharmacology Perspectives

Hemiindigoids comprise a range of natural and synthetic scaffolds that share the same aromatic hydrocarbon backbone as well as promising biological and optical properties. The encouraging therapeutic potential of these scaffolds has been unraveled by many studies over the past years and uncovered representants with inspiring pharmacophoric features such as the acetylcholinesterase inhibitor donezepil and the tubulin polymerization inhibitor indanocine. In this review, we summarize the last advances in the medicinal potential of hemiindigoids, with a special attention to molecular design, structure-activity relationship, ligand-target interactions, and mechanistic explanations covering their effects. As their strong fluorogenic potential and photoswitch behavior recently started to be highlighted and explored in biology, giving rise to the development of novel fluorescent probes and photopharmacological agents, we also discuss these properties in a medicinal chemistry perspective.

Contribution of Knoevenagel Condensation Products towards Development of Anticancer Agents: An Updated Review

Knoevenagel condensation is an entrenched, prevailing, prominent arsenal following greener principles in the generation of α, β-unsaturated ketones/carboxylic acids by involving carbonyl functionalities and active methylenes. This reaction has proved to be a major driving force in many multicomponent reactions indicating the prolific utility towards the development of biologically fascinating molecules. This eminent reaction was acclimatised on different pharmacophoric aldehydes (benzimidazole, β-carboline, phenanthrene, indole, imidazothiadiazole, pyrazole etc.) and active methylenes (oxindole, barbituric acid, Meldrum's acid, thiazolidinedione etc.) to generate the library of chemical compounds. Their potential was also explicit to understand the significance of functionalities involved, which thereby evoke further developments in drug discovery. Furthermore, most of these reaction products exhibited remarkable anticancer activity in nanomolar to micromolar ranges by targeting different cancer targets like DNA, microtubules, Topo-I/II, and kinases (PIM, PARP, NMP, p300/CBP) etc. This review underscores the efficiency of the Knoevenagel condensation explored in the past six-year to generate molecules of pharmacological interest, predominantly towards cancer. The present review also provides the aspects of structure-activity relationships, mode of action and docking study with possible interaction with the target protein.

Therapeutic targeting of PIM KINASE signaling in cancer therapy: Structural and clinical prospects

BACKGROUND

PIM kinases are well-studied drug targets for cancer, belonging to Serine/Threonine kinases family. They are the downstream target of various signaling pathways, and their up/down-regulation affects various physiological processes. PIM family comprises three isoforms, namely, PIM-1, PIM-2, and PIM-3, on alternative initiation of translation and they have different levels of expression in different types of cancers. Its structure shows a unique ATP-binding site in the hinge region which makes it unique among other kinases.

SCOPE OF REVIEW

PIM kinases are widely reported in hematological malignancies along with prostate and breast cancers. Currently, many drugs are used as inhibitors of PIM kinases. In this review, we highlighted the physiological significance of PIM kinases in the context of disease progression and therapeutic targeting. We comprehensively reviewed the PIM kinases in terms of their expression and regulation of different physiological roles. We further predicted functional partners of PIM kinases to elucidate their role in the cellular physiology of different cancer and mapped their interaction network.

MAJOR CONCLUSIONS

A deeper mechanistic insight into the PIM signaling involved in regulating different cellular processes, including transcription, apoptosis, cell cycle regulation, cell proliferation, cell migration and senescence, is provided. Furthermore, structural features of PIM have been dissected to understand the mechanism of inhibition and subsequent implication of designed inhibitors towards therapeutic management of prostate, breast and other cancers.

GENERAL SIGNIFICANCE

Being a potential drug target for cancer therapy, available drugs and PIM inhibitors at different stages of clinical trials are discussed in detail.

An update on benzofuran inhibitors: a patent review

Introduction: Benzofuran is a fundamental unit in numerous bioactive heterocycles. They have attracted chemists and medical researchers due to their broad range of biological activity, where some of them possess unique anticancer, antitubercular, antidiabetic, anti-Alzheimer and anti-inflammatory properties. The benzofuran nucleus is present in a huge number of bioactive natural and synthetic compounds. Benzofuran derivatives have potent applications in pharmaceuticals, agriculture, and polymers. The recent developments considering the biological activities of benzofuran compounds are reported. They have a vital role as pronounced inhibitors against a number of diseases, viruses, fungus, microbes, and enzymes. Areas covered: This review covers the recent developments of biological activities of benzofurans during the period 2014-2019. The covered areas here comprised antimicrobial, anti-inflammatory, antitumor, antitubercular, antidiabetic, anti-Alzheimer, antioxidant, antiviral, vasorelaxant, anti-osteoporotic and enzyme inhibitory activities. Expert opinion: In addition to the already commercialized 34 benzofurans-based drugs in the market, this chapter outlines several potent benzofuran derivatives that may be useful as potential pro-drugs. It is also focused on providing details of SAR and the effect of certain functional groups on the activity of the benzofuran compounds. The presence of -OH, -OMe, sulfonamide, or halogen contributed greatly to increasing the therapeutic activities comparing with reference drugs.

PIM Kinase as an Executional Target in Cancer

PIM (proviral integration site for moloney murine leukemia virus) kinase plays a key role as an oncogene in various cancers including myeloma, leukemia, prostate and breast cancers. The aberrant expression and/or activation of PIM kinases in various cancers follow an isoform-specific pattern. While PIM1 is predominantly expressed in hematological and solid tumors, PIM2 and PIM3 are largely expressed in leukemia and solid tumors, respectively. All of PIM kinases cause transcriptional activation of genes involved in cell survival and cell cycle progression in cancer. A variety of pro-tumorigenic signaling molecules, such as MYC, p21^Cip1/Waf1/p27^kip1, CDC25, Notch1 and BAD have been identified as the downstream targets of PIM kinases. So far, three kinds of adenosine triphosphate-competitive PIM inhibitors, SGI-1776, AZD1208, and LGH447 have been in clinical trials for the treatment of acute myelogenous leukemia, prostate cancer, lymphoma, or multiple myeloma. This review sheds light on the signaling pathways involved in the PIM kinase regulation and current status of developing PIM kinase inhibitors as clinical success in combating human cancer.