The tyrosine kinase inhibitor nilotinib is more efficient than mitotane in decreasing cell viability in spheroids prepared from adrenocortical carcinoma cells

Developing theragnostics for Alzheimer's disease: Insights from cancer treatment

The prevalence of Alzheimer's disease (AD) and its associated economic and societal burdens are on the rise, but there are no curative treatments for AD. Interestingly, this neurodegenerative disease shares several biological and pathophysiological features with cancer, including cell-cycle dysregulation, angiogenesis, mitochondrial dysfunction, protein misfolding, and DNA damage. However, the genetic factors contributing to the overlap in biological processes between cancer and AD have not been actively studied. In this review, we discuss the shared biological features of cancer and AD, the molecular targets of anticancer drugs, and therapeutic approaches. First, we outline the common biological features of cancer and AD. Second, we describe several anticancer drugs, their molecular targets, and their effects on AD pathology. Finally, we discuss how protein-protein interactions (PPIs), receptor inhibition, immunotherapy, and gene therapy can be exploited for the cure and management of both cancer and AD. Collectively, this review provides insights for the development of AD theragnostics based on cancer drugs and molecular targets.

The 3D in vitro Adrenoid cell model recapitulates the complexity of the adrenal gland

The crosstalk between the chromaffin and adrenocortical cells is essential for the endocrine activity of the adrenal glands. This interaction is also likely important for tumorigenesis and progression of adrenocortical cancer and pheochromocytoma. We developed a unique in vitro 3D model of the whole adrenal gland called Adrenoid consisting in adrenocortical carcinoma H295R and pheochromocytoma MTT cell lines. Adrenoids showed a round compact morphology with a growth rate significantly higher compared to MTT-spheroids. Confocal analysis of differential fluorescence staining of H295R and MTT cells demonstrated that H295R organized into small clusters inside Adrenoids dispersed in a core of MTT cells. Transmission electron microscopy confirmed the strict cell-cell interaction occurring between H295R and MTT cells in Adrenoids, which displayed ultrastructural features of more functional cells compared to the single cell type monolayer cultures. Adrenoid maintenance of the dual endocrine activity was demonstrated by the expression not only of cortical and chromaffin markers (steroidogenic factor 1, and chromogranin) but also by protein detection of the main enzymes involved in steroidogenesis (steroidogenic acute regulatory protein, and CYP11B1) and in catecholamine production (tyrosine hydroxylase and phenylethanolamine N-methyltransferase). Mass spectrometry detection of steroid hormones and liquid chromatography measurement of catecholamines confirmed Adrenoid functional activity. In conclusion, Adrenoids represent an innovative in vitro 3D-model that mimics the spatial and functional complexity of the adrenal gland, thus being a useful tool to investigate the crosstalk between the two endocrine components in the pathophysiology of this endocrine organ.

Three Dimensional Models of Endocrine Organs and Target Tissues Regulated by the Endocrine System

Immortalized cell lines originating from tumors and cultured in monolayers in vitro display consistent behavior and response, and generate reproducible results across laboratories. However, for certain endpoints, these cell lines behave quite differently from the original solid tumors. Thereby, the homogeneity of immortalized cell lines and two-dimensionality of monolayer cultures deters from the development of new therapies and translatability of results to the more complex situation in vivo. Organoids originating from tissue biopsies and spheroids from cell lines mimic the heterogeneous and multidimensional characteristics of tumor cells in 3D structures in vitro. Thus, they have the advantage of recapitulating the more complex tissue architecture of solid tumors. In this review, we discuss recent efforts in basic and preclinical cancer research to establish methods to generate organoids/spheroids and living biobanks from endocrine tissues and target organs under endocrine control while striving to achieve solutions in personalized medicine.

Adverse Toxic Effects of Tyrosine Kinase Inhibitors on Non-Target Zebrafish Liver (ZFL) Cells

Over the past 20 years, numerous tyrosine kinase inhibitors (TKIs) have been introduced for targeted therapy of various types of malignancies. Due to frequent and increasing use, leading to eventual excretion with body fluids, their residues have been found in hospital and household wastewaters as well as surface water. However, the effects of TKI residues in the environment on aquatic organisms are poorly described. In the present study, we investigated the cytotoxic and genotoxic effects of five selected TKIs, namely erlotinib (ERL), dasatinib (DAS), nilotinib (NIL), regorafenib (REG), and sorafenib (SOR), using the in vitro zebrafish liver cell (ZFL) model. Cytotoxicity was determined using the MTS assay and propidium iodide (PI) live/dead staining by flow cytometry. DAS, SOR, and REG decreased ZFL cell viability dose- and time-dependently, with DAS being the most cytotoxic TKI studied. ERL and NIL did not affect viability at concentrations up to their maximum solubility; however, NIL was the only TKI that significantly decreased the proportion of PI negative cells as determined by the flow cytometry. Cell cycle progression analyses showed that DAS, ERL, REG, and SOR caused the cell cycle arrest of ZFL cells in the G0/G1 phase, with a concomitant decrease of cells in the S-phase fraction. No data could be obtained for NIL due to severe DNA fragmentation. The genotoxic activity of the investigated TKIs was evaluated using comet and cytokinesis block micronucleus (CBMN) assays. The dose-dependent induction of DNA single strand breaks was induced by NIL (≥2 μM), DAS (≥0.006 μM), and REG (≥0.8 μM), with DAS being the most potent. None of the TKIs studied induced micronuclei formation. These results suggest that normal non-target fish liver cells are sensitive to the TKIs studied in a concentration range similar to those previously reported for human cancer cell lines. Although the TKI concentrations that induced adverse effects in exposed ZFL cells are several orders of magnitude higher than those currently expected in the aquatic environment, the observed DNA damage and cell cycle effects suggest that residues of TKIs in the environment may pose a hazard to non-intentionally exposed organisms living in environments contaminated with TKIs.

Mitotane Nanocarriers for the Treatment of Adrenocortical Carcinoma: Evaluation of Albumin-Stabilized Nanoparticles and Liposomes in a Preclinical In Vitro Study with 3D Spheroids

Adrenocortical carcinoma (ACC) is a heterogeneous malignancy related to poor prognosis and limited treatment options. The orphan drug mitotane (MT) is still a cornerstone in ACC therapy, however, its application is characterized by low aqueous solubility, poor bioavailability, and unfavorable pharmacokinetics, often resulting in below-target plasma concentrations or toxic side effects. Throughout the last decades, nanoparticulate formulations have become attractive carriers to improve anticancer therapy. In this study, injectable MT liposomes (DOPC-MT) and albumin-stabilized MT nanoparticles (BSA-MT) were investigated in depth with respect to their physicochemical properties, and their colloidal and therapeutical stability upon storage. Furthermore, in vitro cytotoxicity was evaluated using the ACC model cell line NCI-H295R for preparing multicellular tumor spheroids, and was compared to non-malignant human dermal fibroblasts. Our results clearly demonstrate that BSA-MT, unlike DOPC-MT, represents a stable and storable MT formulation with a high drug concentration in an aqueous medium. Dual centrifugation was established as a reproducible method for nanoparticle preparation. Although an efficient cytotoxic effect on ACC tumor spheroids was demonstrated, concomitant low toxicity to fibroblasts suggests that higher drug concentrations may be tolerated in vivo. Consequently, BSA-MT is a novel and promising therapeutical approach to address key challenges in MT treatment.

Advances in adrenocortical carcinoma pharmacotherapy: what is the current state of the art?

INTRODUCTION

Surgery, followed or not by adjuvant mitotane, is the current mainstay of therapy for patients with early-stage adrenocortical carcinoma (ACC). Mitotane, either alone or in association with EDP (Etoposide-Doxorubicin-Cisplatin) combination chemotherapy, is the standard approach for patients with metastatic ACC.

AREAS COVERED

The activity of newer cytotoxic drugs, radioligands, targeted therapies and immunotherapy, both in preclinical and in clinical studies, will be reviewed in this paper.

EXPERT OPINION

ADIUVO trial revealed that the administration of adjuvant mitotane is not advantageous in patients with good prognosis. Future strategies are to intensify efforts in adjuvant setting in patients with high risk of relapse. In patients with advanced/metastatic disease, modern targeted therapies have shown significant cytotoxicity in preclinical studies, however, studies in ACC patients reported disappointing results so far. The absence of targeted agents specifically inhibiting the major molecular pathways of ACC growth is the main cause of the failure of these drugs. Since ACC is often antigenic but poorly immunogenic, the results of immunotherapy trials appeared inferior to those achieved in the management of patients with other malignancies. Radioligand therapy may also be a promising approach. Combination of chemotherapy plus immunotherapy could be interesting to be tested in the future.

Nilotinib Improves Bioenergetic Profiling in Brain Astroglia in the 3xTg Mouse Model of Alzheimer's Disease

Current treatments targeting amyloid beta in Alzheimer's disease (AD) have minimal efficacy, which results in a huge unmet medical need worldwide. Accumulating data suggest that brain mitochondrial dysfunction play a critical role in AD pathogenesis. Targeting cellular mechanisms associated with mitochondrial dysfunction in AD create a novel approach for drug development. This study investigated the effects of nilotinib, as a selective tyrosine kinase inhibitor, in astroglia derived from 3xTg-AD mice versus their C57BL/6-controls. Parameters included oxygen consumption rates (OCR), ATP, cytochrome c oxidase (COX), citrate synthase (CS) activity, alterations in oxidative phosphorylation (OXPHOS), nuclear factor kappa B (NF-κB), key regulators of mitochondrial dynamics (mitofusin (Mfn1), dynamin-related protein 1 (Drp1)), and mitochondrial biogenesis (peroxisome proliferator-activated receptor gamma coactivator1-alpha (PGC-1α), calcium/calmodulin-dependent protein kinase II (CaMKII), and nuclear factor (erythroid-derived 2)-like 2 (Nrf2)). Nilotinib increased OCR, ATP, COX, Mfn1, and OXPHOS levels in 3xTg astroglia. No significant differences were detected in levels of Drp1 protein and CS activity. Nilotinib enhanced mitochondrial numbers, potentially through a CaMKII-PGC1α-Nrf2 pathway in 3xTg astroglia. Additionally, nilotinib-induced OCR increases were reduced in the presence of the NF-κB inhibitor, Bay11-7082. The data suggest that NF-κB signaling is intimately involved in nilotinib-induced changes in bioenergetics in 3xTg brain astroglia. Nilotinib increased translocation of the NF-κB p50 subunit into the nucleus of 3xTg astroglia that correlates with an increased expression and activation of NF-κB. The current findings support a role for nilotinib in improving mitochondrial function and suggest that astroglia may be a key therapeutic target in treating AD.

Nilotinib, A Tyrosine Kinase Inhibitor, Suppresses the Cell Growth and Triggers Autophagy in Papillary Thyroid Cancer

BACKGROUND

Papillary thyroid carcinoma (PTC) represents for the most common thyroid cancer. Until recently, treatment options for PTC patients are limited. Nilotinib is the second-generation tyrosine kinase inhibitor, and has been widely used in the treatment of chronic myeloid leukemia (CML).

OBJECTIVES

We aimed to explore whether nilotinib is effective in PTC cancer progression and the underlying mechanisms.

METHODS

In this study, the three human PTC cell lines (KTC-1, BCPAP, and TPC1) were used to verify the effects of nilotinib on cell growth. The half maximal inhibitory concentration (IC50) was calculated according to the growth curve post nilotinib treatment at different concentrations. Cell counting kit-8 and colony formation analysis were used to monitor cell growth after nilotinib treatment. Cell apoptosis and autophagy related proteins and phosphorylation of PI3K/Akt/mTOR were detected by Western blotting analysis.

RESULTS

Nilotinib treatment can effectively inhibit PTC cell growth, which was accompanied by increase of apoptosis and induction of autophagy. Mechanistically, nilotinib treatment repressed the phosphorylation of PI3K/Akt/mTOR pathway.

CONCLUSION

Collectively, our results demonstrated that nilotinib may display anti-tumor effect against PTC via inhibiting of PI3K/Akt/mTOR pathway and inducing apoptosis and autophagy.

SIRT1 is involved in adrenocortical cancer growth and motility

Adrenocortical cancer (ACC) is a rare tumour with unfavourable prognosis, lacking an effective treatment. This tumour is characterized by IGF‐II (insulin‐like growth factor II) overproduction, aromatase and ERα (oestrogen receptor alpha) up‐regulation. Previous reports suggest that ERα expression can be regulated by sirt1 (sirtuin 1), a nicotinamide adenine dinucleotide (NAD+)‐dependent class III histone deacetylases that modulates activity of several substrates involved in cellular stress, metabolism, proliferation, senescence, protein degradation and apoptosis. Nevertheless, sirt1 can act as a tumour suppressor or oncogenic protein. In this study, we found that in H295R and SW13 cell lines, sirt1 expression is inhibited by sirtinol, a potent inhibitor of sirt1 activity. In addition, sirtinol is able to decrease ACC cell proliferation, colony and spheroids formation and to activate the intrinsic apoptotic mechanism. Particularly, we observed that sirtinol interferes with E2/ERα and IGF1R (insulin growth factor 1 receptor) pathways by decreasing receptors expression. Sirt1 involvement was confirmed by using a specific sirt1 siRNA. More importantly, we observed that sirtinol can synergize with mitotane, a selective adrenolitic drug, in inhibiting adrenocortical cancer cell growth. Collectively, our data reveal an oncogenic role for sirt1 in ACC and its targeting could implement treatment options for this type of cancer.

The Role of Biomarkers in Adrenocortical Carcinoma: A Review of Current Evidence and Future Perspectives

Adrenocortical carcinoma (ACC) is a rare endocrine malignancy arising from the adrenal cortex often with unexpected biological behavior. It can occur at any age, with two peaks of incidence: in the first and between fifth and seventh decades of life. Although ACC are mostly hormonally active, precursors and metabolites, rather than end products of steroidogenesis are produced by dedifferentiated and immature malignant cells. Distinguishing the etiology of adrenal mass, between benign adenomas, which are quite frequent in general population, and malignant carcinomas with dismal prognosis is often unfeasible. Even after pathohistological analysis, diagnosis of adrenocortical carcinomas is not always straightforward and represents a great challenge for experienced and multidisciplinary expert teams. No single imaging method, hormonal work-up or immunohistochemical labelling can definitively prove the diagnosis of ACC. Over several decades' great efforts have been made in finding novel reliable and available diagnostic and prognostic factors including steroid metabolome profiling or target gene identification. Despite these achievements, the 5-year mortality rate still accounts for approximately 75% to 90%, ACC is frequently diagnosed in advanced stages and therapeutic options are unfortunately limited. Therefore, imperative is to identify new biological markers that can predict patient prognosis and provide new therapeutic options.

Advanced Adrenocortical Carcinoma (ACC): a Review with Focus on Second-Line Therapies

Advanced adrenocortical cancer (ACC) is a rare, highly aggressive malignancy, which typically has a poor prognosis. In advanced ACC, the overall trend is toward a short PFS interval following first-line systemic therapy, highlighting a clear need for improved second-/third-line treatment strategies. We conducted a review of the literature and relevant scientific guidelines related to systemic therapy for advanced ACC. Public indexes including PubMed/MEDLINE were searched. Treatment selection in the second-line setting is based on small phase 2 trials, case reports, and pre-clinical evidence. The best data available for initial second-line therapy selection supports the use of gemcitabine and capecitabine (G + C) or streptozotocin (S), both with or without mitotane. G + C is becoming increasingly recommended based on phase 2 clinical trial data in patients of good PS, due to the inferred superior PFS and OS from non-comparative trials. Alternatively, streptozotocin was better tolerated than EDP + M in the FIRM-ACT study and remains an option when warranted. Beyond this, further treatment approaches should be tailored to individual patient characteristics, utilizing a mixture of systemic therapies, local therapies, and enrolment in clinical trials where available. Additionally, the role of molecular stratification, predictive biomarkers, and immune checkpoint inhibitors in specific individuals, such as Lynch syndrome, is evolving and may become increasingly utilized in clinical practice. Advanced ACC necessitates a multidisciplinary approach and is best managed in a specialist center. Although there is no one definitive second-line treatment strategy, there are some favorable approaches, which require further validation in larger clinical trials.

A Micellar Mitotane Formulation with High Drug-Loading and Solubility: Physico-Chemical Characterization and Cytotoxicity Studies in 2D and 3D In Vitro Tumor Models

Adrenocortical carcinoma (ACC) is a rare tumor and prognosis is overall poor but heterogeneous. Mitotane (MT) has been used for treatment of ACC for decades, either alone or in combination with cytotoxic chemotherapy. Even at doses up to 6 g per day, more than half of the patients do not achieve targeted plasma concentration (14-20 mg L^-1 ) even after many months of treatment due to low water solubility, bioavailability, and unfavorable pharmacokinetic profile. Here a novel MT nanoformulation with very high MT concentrations in physiological aqueous media is reported. The MT-loaded nanoformulations are characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, and powder X-ray diffraction which confirms the amorphous nature of the drug. The polymer itself does not show any cytotoxicity in adrenal and liver cell lines. By using the ACC model cell line NCI-H295 both in monolayers and tumor cell spheroids, micellar MT is demonstrated to exhibit comparable efficacy to its ethanol solution. It is postulated that this formulation will be suitable for i.v. application and rapid attainment of therapeutic plasma concentrations. In conclusion, the micellar formulation is considered a promising tool to alleviate major drawbacks of current MT treatment while retaining bioactivity toward ACC in vitro.