Combination of fenretinide and indole-3-carbinol results in synergistic cytotoxic activity inducing apoptosis against human breast cancer cells in vitro

Navigating The Deuteration Landscape: Innovations, Challenges, and Clinical Potential of Deuterioindoles

Indoles, pivotal to the realm of drug discovery, underpin numerous FDA-approved therapeutics. Despite their clinical benefits, pharmacokinetic and toxicity concerns have occasionally hampered their broader application. A notable advancement in this domain is the substitution of hydrogen atoms with deuterium, known as deuterium modification, which significantly enhances the pharmacological properties of these compounds. This review elucidates the progression of deuterium chemistry, culminating in approval of Deutetrabenazine in 2017. This milestone has catalyzed additional research into deuterated indoles, such as Dosimertinib, which have demonstrated enhancements in stability, toxicity profiles, and therapeutic efficacy. Moreover, the review addresses challenges and patent issues in the synthesis of deuterated indoles and highlights their potential applications in precision medicine. In the future, deuterated indoles may positively impact therapy and contribute to advances in precision medicine through molecular engineering.

Fenretinide induces apoptosis and synergises the apoptosis inducing effect of gemcitabine through inhibition of key signalling molecules involved in A549 cell survival in in silico and in vitro analyses

Fenretinide is a synthetic retinoid compound, which induces apoptosis via generating reactive oxygen species (ROS) and modulating PI3K/Akt/mTOR signalling pathway. We hypothesise that fenretinide's mechanism of action in triggering apoptosis may involve other targets, beside mTOR signalling pathway and it may augment apoptosis inducing effects of chemotherapeutic drugs in lung cancer. Time-lapse microscopy and Western blotting were used to evaluate apoptosis and apoptotic marker cleaved-Caspase 3 in A549 cells. Relative levels of protein phosphorylation and ROS were quantified by Human Phospho-Kinase Array Kit and CellROX® Green Reagent, respectively. Docking and simulation analyses of proteins and fenretinide interactions were identified and visualised by Discovery Studio Visualizer and AutoDock Vina software. Our results showed that fenretinide induced apoptosis in a dose dependant manner and combinations of fenretinide (5 μg/mL) and gemcitabine (1, 2, 4, 8 and 16 μg/mL) synergistically enhanced apoptosis in A549 cells. Fenretinide caused significant increase of cleaved-Caspase 3, de-phosphorylated p-S473 of Akt and failed to inhibit mTORC1 downstream targets. In silico results revealed that Akt required the lowest energy (-10.2 kcal/mol) to interact with fenretinide in comparison with other proteins. In conclusion, Akt may be exploited as a good target for induction of apoptosis in A549 cells and fenretinide has great potentials to fulfil this task. The mechanism by which fenretinide boosts the apoptosis inducing effects of gemcitabine, which is likely expected to be via inhibiting mTORC2 downstream targets. However, docking investigation revealed that fenretinide lacks specificity as it may also interact with several secondary targets beside Akt.

Maximizing the value of indole-3-carbinol, from its distribution in dietary sources, health effects, metabolism, extraction, and analysis in food and biofluids

Indole-3-carbinol (I3C) is a major dietary component produced in Brassica vegetables from glucosinolates (GLS) upon herbivores' attack. The compound is gaining increasing interest due to its anticancer activity. However, reports about improving its level in plants or other sources are still rare. Unfortunately, I3C is unstable in acidic media and tends to polymerize rendering its extraction and detection challenging. This review presents a multifaceted overview of I3C regarding its natural occurrence, biosynthesis, isolation, and extraction procedure from dietary sources, and optimization for the best recovery yield. Further, an overview is presented on its metabolism and biotransformation inside the body to account for its health benefits and factors to ensure the best metabolic yield. Compile of the different analytical approaches for I3C analysis in dietary sources is presented for the first time, together with approaches for its detection and its metabolism in body fluids for proof of efficacy. Lastly, the chemopreventive effects of I3C and the underlying action mechanisms are summarized. Optimizing the yield and methods for the detection of I3C will assist for its incorporation as a nutraceutical or adjuvant in cancer treatment programs. Highlighting the complete biosynthetic pathway and factors involved in I3C production will aid for its future biotechnological production.

Cabazitaxel exhibits more favorable molecular changes compared to other taxanes in androgen-independent prostate cancer cells

Taxane-based chemotherapy drugs (cabazitaxel, docetaxel, and paclitaxel) are microtubule inhibitors, which are effectively and frequently used to treat metastatic prostate cancer (PCa). Among these, cabazitaxel is offered as a new therapeutic option for patients with metastatic castration-resistant PC as that are resistant to other taxanes. Here, we investigated the cellular and molecular changes in response to cabazitaxel in comparison with docetaxel and paclitaxel in androgen-independent human PCas. The androgen-independent human PCa cell lines, PC3 and DU145, were treated with 1 to 5nM cabazitaxel, docetaxel, or paclitaxel, and assessed for cell viability (MTT assay), colony forming ability and migration (scratch assay). The induction of apoptosis was determined through measurement of mitochondrial membrane potential (JC-1 assay) and caspase-3 activity assay. The protein expression changes (caspase-3, caspase-8, Bax, Bcl-2, β-tubulin, nuclear factor-κB [NF-κB/p50, NF-κB/p65], vascular endothelial growth factor, WNT1-inducible signaling pathway protein-1 [WISP1], transforming growth factor β [TGF-β]) in response to drug treatment were screened via western blotting. Under our experimental conditions, all taxanes significantly reduced WISP1 and TGF-β expressions, suggesting an anti-metastatic/antiangiogenic effect for these drugs. On the other hand, cabazitaxel induced more cell death and inhibited colony formation compared to docetaxel or paclitaxel. The highest fold change in caspase-3 activity and Bax/Bcl-2 ratio was also detected in response to cabazitaxel. Furthermore, the induction of β-tubulin expression was lower in cabazitaxel-treated cells relative to the other taxanes. In summary, cabazitaxel shows molecular changes in favor of killing PCa cells compared to other taxanes, at least for the parameters analyzed herein. The differences with other taxanes may be important while designing other studies or in clinical settings.

The role of cell cycle progression for the apoptosis of cancer cells induced by palladium(II)-saccharinate complexes of terpyridine

OBJECTIVES

Palladium complexes are potent and less toxic molecules in comparison to other metal based agents. Here, we characterized two palladium(II) saccharinate complexes with terpyridine for their cell cycle specificity.

MATERIALS AND METHODS

Cells were arrested at G1, G1/S boundary or mitosis using mimosine, double-Thymidine block, aphidicolin, nocodazole or colcemid, and evaluated based on morphology and flow cytometry. Synchronized cells were treated with the Pd(II) complexes, and viability was measured via MTT assay.

RESULTS

While treatment of arrested cells with the Pd(II) complexes resulted in no significant change in cell death in HCT-116 and MDA-MB-231 cells, HeLa cells were more sensitive in S/G1. The main form of cell death was found to be apoptosis.

CONCLUSIONS

Pd(II) complexes appear to be cell-cycle non-specific, while cell line dependent differences may be observed. Cells die through apoptosis regardless of the cell cycle stage, which makes these complexes more promising as anti-cancer agents.

Validation data supporting the characterization of novel copper complexes as anticancer agents

Three copper(II) complexes, Cu(Sal-Gly)(phen), Cu(Sal-Gly)pheamine, Cu(Sal-Gly)phepoxy were synthesized and characterized for their anticancer properties and mechanism of action (Acilan et al., in press) [1]. Here, we provide supporting data on colon cancer cell lines complementing our previous findings in cervix cells. This paper also contains a data table for the fold changes and p-values of all genes analyzed in this study via a custom RT-qPCR array. All compounds induced DNA damage (based on 8-oxo-guanidine, ɣH2AX staining in cells) and apoptosis (based on elevated DNA condensation/fragmentation, Annexin V staining, caspase 3/7 activity and mitochondrial membrane depolarization) in HCT-116 colon cancer cells. The increase in oxidative stress was also further confirmed in these cells. Further interpretation of the data presented here can be found in the article entitled “Synthesis, biological characterization and evaluation of molecular mechanisms of novel copper complexes as anticancer agents” (Acilan et al., in press) [1].

Fenretinide (4-HPR) Targets Caspase-9, ERK 1/2 and the Wnt3a/β-Catenin Pathway in Medulloblastoma Cells and Medulloblastoma Cell Spheroids

Medulloblastoma (MB), a neuroectodermal tumor arising in the cerebellum, represents the most frequent childhood brain malignancy. Current treatments for MB combine radiation and chemotherapy and are often associated with relevant side effects; novel therapeutic strategies are urgently needed. N-(4-Hydroxyphenyl) retinamide (4-HPR, fenretinide), a synthetic analogue of all-trans retinoic acid, has emerged as a promising and well-tolerated cancer chemopreventive and chemotherapeutic agent for various neoplasms, from breast cancer to neuroblastoma. Here we investigated the effects of 4-HPR on MB cell lines and identified the mechanism of action for a potential use in therapy of MB. Flow cytometry analysis was performed to evaluate 4-HPR induction of apoptosis and oxygen reactive species (ROS) production, as well as cell cycle effects. Functional analysis to determine 4-HPR ability to interfere with MB cell migration and invasion were performed. Western Blot analysis were used to investigate the crucial molecules involved in selected signaling pathways associated with apoptosis (caspase-9 and PARP-1), cell survival (ERK 1/2) and tumor progression (Wnt3a and β-catenin). We show that 4-HPR induces caspase 9-dependent cell death in DAOY and ONS-76 cells, associated with increased ROS generation, suggesting that free radical intermediates might be directly involved. We observed 4-HPR induction of cell cycle arrest in G1/S phase, inactivated β-catenin, and inhibition of MB cell migration and invasion. We also evaluated the ability of 4-HPR to target MB cancer-stem/cancer-initiating cells, using an MB spheroids model, followed by flow cytometry and quantitative real-time PCR. 4-HPR treatment reduced DAOY and ONS-76 spheroid formation, in term of number and size. Decreased expression of the surface markers CD133⁺ and ABCG2⁺ as well as Oct-4 and Sox-2 gene expression were observed on BTICs treated with 4-HPR further reducing BITIC invasive activities. Finally, we analyzed 4-HPR ability to inhibit MB tumor cell growth in vivo in nude mice. Taken together, our data suggest that 4-HPR targets both parental and MB tumor stem/initiating cell-like populations. Since 4-HPR exerts low toxicity, it could represent a valid compound in the treatment of human MB.

Evaluation of genotoxic and apoptotic potential of Hypericum adenotrichum Spach. in vitro

Hypericum adenotrichum Spach. is an endemic plant from Turkey that is also used in folk medicine. In this study, following analyses of its chemical composition, the genotoxic/antigenotoxic effects of the methanol extract of H. adenotrichum in human lymphocyte culture were investigated using in vitro sister chromatid exchange, micronucleus and comet assays. In addition, the anti-growth effect of the extract was investigated in human breast cancer cell lines (MCF-7 and MDA-MB-231) using MTT and ATP viability assays. The mode of cell death was determined using fluorescence microscopy and biochemical methods. We found that the H. adenotrichum extract demonstrated cytotoxic and genotoxic effects in a cell type-dependent manner. At selected doses (125-500 μg/ml), the H. adenotrichum extract exhibited significant genotoxic activity in human lymphocytes, whereas it showed anti-growth effects on cancer cell lines between 0.2 and 100 μg/ml concentrations. The mode of cell death in cancer cells was shown to be apoptosis due to the presence of pyknotic nuclei, the cleavage of poly-(ADP-ribose) polymerase (PARP) and/or the activation of caspase-3. These results suggest that H. adenotrichum might show both cytotoxic and genotoxic effects depending on the cell type. This should be taken into account in its use for therapeutic purposes.