Approximately half of glioblastoma and more than two-thirds of grade II and III glioma tumors lack the DNA repair protein O 6 -methylguanine methyl transferase (MGMT). MGMT-deficient tumors respond initially to the DNA methylation agent temozolomide (TMZ) but frequently acquire resistance through loss of the mismatch repair (MMR) pathway. We report the development of agents that overcome this resistance mechanism by inducing MMR-independent cell killing selectively in MGMT-silenced tumors. These agents deposit a dynamic DNA lesion that can be reversed by MGMT but slowly evolves into an interstrand cross-link in MGMT-deficient settings, resulting in MMR-independent cell death with low toxicity in vitro and in vivo. This discovery may lead to new treatments for gliomas and may represent a new paradigm for designing chemotherapeutics that exploit specific DNA repair defects.

Glioblastomas are a subtype of gliomas, which are the most aggressive and deadly form of brain tumours. The epidermal growth factor receptor (EGFR) is over-expressed and amplified in glioblastomas. Luteolin is a common bioflavonoid found in a variety of fruits and vegetables. The aim of this study was to explore the molecular and biological effects of luteolin on EGF-induced cell proliferation and the potential of luteolin to induce apoptosis in glioblastoma cells. In vitro cell viability assays demonstrated that luteolin decreased cell proliferation in the presence or absence of EGF. Immunoblots revealed that luteolin decreased the protein expression levels of phosphorylated Akt, mTOR, p70S6K and MAPK in the presence of EGF. Furthermore, our results revealed the ability of luteolin to induce caspase and PARP cleavages in glioblastoma cells in addition to promoting cell cycle arrest. Our results demonstrated that luteolin has an inhibitory effect on downstream signalling molecules activated by EGFR, particularly the Akt and MAPK signalling pathways, and provided a rationale for further clinical investigation into the use of luteolin as a therapeutic molecule in the management of glioblastoma.

Objectives Glioblastoma (GBM) is highly proliferative, infiltrative, malignant and the most deadly form of brain tumour. The epidermal growth factor receptor (EGFR) is overexpressed, amplified and mutated in GBM and has been shown to play key and important roles in the proliferation, growth and survival of this tumour. The goal of our study was to investigate the antiproliferative, apoptotic and molecular effects of apigenin in GBM. Methods Proliferation and viability tests were carried out using the trypan blue exclusion, MTT and lactate dehydrogenase (LDH) assays. Flow cytometry was used to examine the effects of apigenin on the cell cycle check-points. In addition, we determined the effects of apigenin on EGFR-mediated signalling pathways by Western blot analyses. Key findings Our results showed that apigenin reduced cell viability and proliferation in a dose-and time-dependent manner while increasing cytotoxicity in GBM cells. Treatment with apigenin-induced is poly ADP-ribose polymerase (PARP) cleavage and caused cell cycle arrest at the G2M checkpoint. Furthermore, our data revealed that apigenin inhibited EGFR-mediated phosphorylation of mitogen-activated protein kinase (MAPK), AKT and mammalian target of rapamycin (mTOR) signalling pathways and attenuated the expression of Bcl-xL. Conclusion Our results demonstrated that apigenin has potent inhibitory effects on pathways involved in GBM proliferation and survival and could potentially be used as a therapeutic agent for GBM.

Humankind has used and abused psychoactive drugs for millennia. Formally, a psychoactive drug is any agent that alters cognition and mood. The term “psychotropic drug” is neutral and describes the entire class of substrates, licit and illicit, of interest to governmental drug policy. While these drugs are prescribed for issues ranging from pain management to anxiety, they are also used recreationally. In fact, the current opioid epidemic is the deadliest drug crisis in American history. While the topic is highly politicized with racial, gender, and socioeconomic elements, there is no denying the toll drug mis- and overuse is taking on this country. Overdose, fueled by opioids, is the leading cause of death for Americans under 50 years of age, killing ca. 64,000 people in 2016. From a chemistry standpoint, the question is in what ways, if any, did organic chemists contribute to this problem? In this targeted review, we provide brief historical accounts of the main classes of psychoactive drugs and discuss several foundational total syntheses that ultimately provide the groundwork for producing these molecules in academic, industrial, and clandestine settings.

Herein, we report the synthesis and structure–activity relationship of a series of chiral alkoxymethyl morpholine analogs. Our efforts have culminated in the identification of (S)-2-(((6-chloropyridin-2-yl) oxy)methyl)-4-((6-fluoro-1H-indol-3-yl)methyl)morpholine as a novel potent and selective dopamine D4 receptor antagonist with selectivity against the other dopamine receptors tested (<10% inhibition at 1 µM against D1, D2L, D2S, D3, and D5).