Chlorpromazine affects glioblastoma bioenergetics by interfering with pyruvate kinase M2.

Glioblastoma (GBM) is the most frequent and lethal brain tumor, whose therapeutic outcome - only partially effective with current schemes - places this disease among the unmet medical needs, and effective therapeutic approaches are urgently required. In our attempts to identify repositionable drugs in glioblastoma therapy, we identified the neuroleptic drug chlorpromazine (CPZ) as a very promising compound. Here we aimed to further unveil the mode of action of this drug. We performed a supervised recognition of the signal transduction pathways potentially influenced by CPZ via Reverse-Phase Protein microArrays (RPPA) and carried out an Activity-Based Protein Profiling (ABPP) followed by Mass Spectrometry (MS) analysis to possibly identify cellular factors targeted by the drug. Indeed, the glycolytic enzyme PKM2 was identified as one of the major targets of CPZ. Furthermore, using the Seahorse platform, we analyzed the bioenergetics changes induced by the drug. Consistent with the ability of CPZ to target PKM2, we detected relevant changes in GBM energy metabolism, possibly attributable to the drug's ability to inhibit the oncogenic properties of PKM2. RPE-1 non-cancer neuroepithelial cells appeared less responsive to the drug. PKM2 silencing reduced the effects of CPZ. 3D modeling showed that CPZ interacts with PKM2 tetramer in the same region involved in binding other known activators. The effect of CPZ can be epitomized as an inhibition of the Warburg effect and thus malignancy in GBM cells, while sparing RPE-1 cells. These preclinical data enforce the rationale that allowed us to investigate the role of CPZ in GBM treatment in a recent multicenter Phase II clinical trial.

A diagnostic circulating miRNA signature as orchestrator of cell invasion via TKS4/TKS5/EFHD2 modulation in human gliomas.

BACKGROUND: Altered microRNA profiles have been observed not only in tumour tissues but also in biofluids, where they circulate in a stable form thus representing interesting biomarker candidates. This study aimed to identify a microRNA signature as a non-invasive biomarker and to investigate its impact on glioma biology. METHODS: MicroRNAs were selected using a global expression profile in preoperative serum samples from 37 glioma patients. Comparison between serum samples from age and gender-matched controls was performed by using the droplet digital PCR. The ROC curve and Kaplan-Meier survival analyses were used to evaluate the diagnostic/prognostic values. The functional role of the identified signature was assessed by gain/loss of function strategies in glioma cells. RESULTS: A three-microRNA signature (miR-1-3p/-26a-1-3p/-487b-3p) was differentially expressed in the serum of patients according to the isocitrate dehydrogenase (IDH) genes mutation status and correlated with both patient Overall and Progression Free Survival. The identified signature was also downregulated in the serum of patients compared to controls. Consistent with these results, the signature expression and release in the conditioned medium of glioma cells was lower in IDH-wild type cells compared to the mutated counterpart. Furthermore, in silico analysis of glioma datasets showed a consistent deregulation of the signature according to the IDH mutation status in glioma tumour tissues. Ectopic expression of the signature negatively affects several glioma functions. Notably, it impacts the glioma invasive phenotype by directly targeting the invadopodia-related proteins TKS4, TKS5 and EFHD2. CONCLUSIONS: We identified a three microRNA signature as a promising complementary or even an independent non-invasive diagnostic/prognostic biomarker. The signature displays oncosuppressive functions in glioma cells and impacts on proteins crucial for migration and invasion, providing potential targets for therapeutic intervention.

MiR-22, a serum predictor of poor outcome and therapy response in diffuse large B-cell lymphoma patients.

Diffuse large B-cell lymphoma (DLBCL) is an aggressive, heterogeneous neoplasm where prognostication and therapeutic decision are challenging. The available prognostic tools are not able to identify all patients refractory to treatment. MicroRNAs, small RNAs frequently deregulated in cancer, stably circulate in biofluids, representing interesting candidates for non-invasive biomarkers. Here we validated serum miR-22, an evolutionarily conserved microRNA, as a prognostic/predictive biomarker in DLBCL. Moreover, we found that its expression and release from DLBCL cells are related to therapy response and adversely affect cell proliferation. These results suggest that miR-22 is a promising complementary or even independent non-invasive biomarker for DLBCL management.

Dropwort-induced metabolic reprogramming restrains YAP/TAZ/TEAD oncogenic axis in mesothelioma.

BACKGROUND: Over the past decade, newly designed cancer therapies have not significantly improved the survival of patients diagnosed with Malignant Pleural Mesothelioma (MPM). Among a limited number of genes that are frequently mutated in MPM several of them encode proteins that belong to the HIPPO tumor suppressor pathway. METHODS: The anticancer effects of the top flower standardized extract of Filipendula vulgaris (Dropwort) were characterized in "in vitro" and "in vivo" models of MPM. At the molecular level, two "omic" approaches were used to investigate Dropwort anticancer mechanism of action: a metabolomic profiling and a phosphoarray analysis. RESULTS: We found that Dropwort significantly reduced cell proliferation, viability, migration and in vivo tumor growth of MPM cell lines. Notably, Dropwort affected viability of tumor-initiating MPM cells and synergized with Cisplatin and Pemetrexed in vitro. Metabolomic profiling revealed that Dropwort treatment affected both glycolysis/tricarboxylic acid cycle as for the decreased consumption of glucose, pyruvate, succinate and acetate, and the lipid metabolism. We also document that Dropwort exerted its anticancer effects, at least partially, promoting YAP and TAZ protein ubiquitination. CONCLUSIONS: Our findings reveal that Dropwort is a promising source of natural compound(s) for targeting the HIPPO pathway with chemo-preventive and anticancer implications for MPM management.

Antibody Array as a Tool for Screening of Natural Agents in Cancer Chemoprevention.

The efficacy of a given drug resides mainly on its ability to specifically target disease mechanisms. Natural products represent the leading source of bioactive molecules with a broad range of activities. It is becoming increasingly clear that natural compounds exert their chemopreventive or antitumoral activities targeting simultaneously diverse cellular pathways. Here we describe the use of antibody array to assess the effects of natural compounds on the expression of multiple proteins and of their posttranslational modifications in cellular systems. This might turn to be a very flexible application for cancer chemoprevention studies.

Cynara scolymus affects malignant pleural mesothelioma by promoting apoptosis and restraining invasion.

Malignant pleural mesothelioma is a poorly treated neoplasia arising from the pleural mesothelial lining. Here we document that the leaf extract of Cynara scolymus exerts broad antitumoral effects both in vitro and in vivo on mesothelioma cell lines. We found that Cynara scolymus treatment affects strongly cell growth, migration and tumor engraftment of mesothelioma cell lines. Strikingly, dietary feeding with Cynara scolymus leaf extract reduces the growth of mesothelioma xenografted tumors similarly to pemetrexed, a commonly employed drug in the treatment of mesothelioma. In aggregate our findings suggest that leaf extract of Cynara scolymus holds therapeutic potential for the treatment of mesothelioma.