Induced Effect of Zinc oxide nanoparticles on human acute myeloid leukemia cell apoptosis by regulating mitochondrial division

Synthesis of Zinc Oxide-Doped Carbon Dots for Treatment of Triple-Negative Breast Cancer

Introduction

The anti-cancer properties of zinc oxide-doped carbon dots (CDs/ZnO) in inhibiting triple-negative breast cancer (TNBC) progression merit more investigation.

Methods

With citric acid as the carbon source, urea applied as the nitrogen source, and zinc oxide (ZnO) used as a reactive dopant, CDs/ZnO were synthesized by microwave heating in the current study, followed by the characterization and biocompatibility assessments. Subsequently, the anti-cancer capabilities of CDs/ZnO against TNBC progression were evaluated by various biochemical and molecular techniques, including viability, proliferation, migration, invasion, adhesion, clonogenicity, cell cycle distribution, apoptosis, redox homeostasis, metabolome, and transcriptome assays of MDA-MB-231 cells. Additionally, the in vivo anti-cancer potentials of CDs/ZnO against TNBC progression were analyzed using TNBC xenograft mouse models.

Results

The biocompatibility of CDs/ZnO was supported by the non-significant changes in the pathological and physiological parameters in the CDs/ZnO treated mice, alongside a non-cytotoxic effect of CDs/ZnO on the proliferation of normal cells. Notably, the CDs/ZnO treatments effectively decreased the viability, proliferation, migration, invasion, adhesion, and clonogenicity of MDA-MB-231 cells. Furthermore, the CDs/ZnO treatments induced cell cycle arrest, apoptosis, redox imbalance, metabolome disturbances, and transcriptomic alterations of MDA-MB-231 cells by regulating the MAPK signaling pathway. Additionally, the CDs/ZnO treatments markedly suppressed the in vivo tumor growth in the TNBC xenograft mouse models.

Conclusion

In this study, we synthesized CDs/ZnO via microwave heating, using citric acid as the carbon source, urea as the nitrogen source, and ZnO as a reactive dopant. We confirmed the biosafety and potent anti-cancer efficacy of CDs/ZnO in inhibiting TNBC progression by disrupting malignant cell behaviors through modulation of the MAPK signaling pathway.

Zinc-Based Nanoparticles, but Not Silicon-Based Nanoparticles, Accumulate in Mitochondria and Promote Cell Death in Liver Cancer Cells

Introduction

Hepatocellular carcinoma (HCC) is the main hepatic primary malignancy. Patients with advanced HCC receiving the recommended therapies have a poor outcome. In different settings, nanotechnology has gained attraction as a potential alternative strategy for improving therapeutic effectiveness. Among several nanoparticles (NPs), inorganic NPs, such as zinc and silicon oxides (ZnO and SiO2), are mainly chosen as drug nanocarriers, as both present great adsorption properties and biocompatibility.

Aim

The objective is to identify the molecular mechanisms underlying the proapoptotic effects of ZnO and SiO2 NPs in differentiated hepatoblastoma cells (HepG2) and mesenchymal liver cancer cells (SNU449).

Methods

Dose-dependent induction of cell cytotoxicity by ZnO and SiO2 NPs (5 to 50 µg/mL) was determined in HepG2 and SNU449 cells. NPs intracellular localization was assessed using transmission electron microscopy (TEM). Cell death was determined by trypan blue staining and caspase-3 and -8 activities. Cell respiration was determined using MitroStress assay (Seahorse, Agilent).

Results

ZnO NPs, but not SiO2 NPs, reduced cell viability in HepG2 and SNU449. Interestingly, SNU449 appeared to be more susceptible than HepG2 to ZnO NPs (IC50 of 27.4 ± 1.4 µg/mL and 41.8 ± 0.4 µg/mL, respectively). SiO2 NPs tended to be localized in lysosomes in both cell lines, while ZnO NPs demonstrated a random distribution with a high presence in mitochondria and related structures. As expected, SiO2 NPs did not reduce cell survival and cell respiration, while ZnO NPs promoted cell death and decreased oxygen consumption rate. ZnO NPs mitochondrial accumulation was associated with increased apoptosis in HepG2, while necroapoptosis was mainly involved in ZnO-induced cell death in SNU449.

Conclusion

SiO2 demonstrated no cytotoxic profile against liver cancer cells. ZnO NPs demonstrated to accumulate in mitochondria impacting cell respiration and cell death in liver cancer cells. ZnO induced apoptosis and necroptosis in HepG2 and SNU449, respectively.

ZnO Nanoparticles as Potent Inducers of Dermal Immunosuppression in Contact Hypersensitivity in Mice

Nanosized zinc oxide (nZnO) metal particles are used in skin creams and sunscreens to enhance their texture and optical properties as UV filters. Despite their common use, little is known about the molecular mechanisms of nZnO exposure on damaged skin. We studied the effects of topically applied nZnO particles on allergic skin inflammation in an oxazolone (OXA)-induced contact hypersensitivity (CHS) mouse model. We investigated whether exposure to nZnO during the sensitization or challenge phase would induce immunological changes and modulate transcriptional responses. We followed skin thickness, cellular infiltration, and changes in the local transcriptome up to 28 days after the challenge. The responses peaked at 24 h and were fully resolved by 28 days. Co-exposure to nZnO and hapten did not interfere with the formation of the sensitization process. Conversely, during the hapten challenge, the application of nZnO fully suppressed the development of the CHS response by the inhibition of pro-inflammatory pathways, secretion of pro-inflammatory cytokines, and proliferation of immune cells. In differentiated and stimulated THP-1 cells and the CHS mouse model, we found that nZnO particles and Zn ions contributed to anti-inflammatory responses. The immunosuppressive properties of nZnO in inflamed skin are mediated by impaired IL-1R-, CXCR2-, and LTB4-mediated pathways. nZnO-induced dermal immunosuppression may be beneficial for individuals with contact allergies who use nZnO-containing cosmetic products. Our findings also provide a deeper understanding of the mechanisms of nZnO, which could be considered when developing nanoparticle-containing skin products.

Advances in Drug Delivery Systems for the Treatment of Acute Myeloid Leukemia

Acute myeloid leukemia (AML) is a common and catastrophic hematological neoplasm with high mortality rates. Conventional therapies, including chemotherapy, hematopoietic stem cell transplantation (HSCT), immune therapy, and targeted agents, have unsatisfactory outcomes for AML patients due to drug toxicity, off-target effects, drug resistance, drug side effects, and AML relapse and refractoriness. These intrinsic limitations of current treatments have promoted the development and application of nanomedicine for more effective and safer leukemia therapy. In this review, the classification of nanoparticles applied in AML therapy, including liposomes, polymersomes, micelles, dendrimers, and inorganic nanoparticles, is reviewed. In addition, various strategies for enhancing therapeutic targetability in nanomedicine, including the use of conjugating ligands, biomimetic-nanotechnology, and bone marrow targeting, which indicates the potential to reverse drug resistance, are discussed. The application of nanomedicine for assisting immunotherapy is also involved. Finally, the advantages and possible challenges of nanomedicine for the transition from the preclinical phase to the clinical phase are discussed.

Zinc Oxide Nanoparticles and Cancer Chemotherapy: Helpful Tools for Enhancing Chemo-sensitivity and Reducing Side Effects?

Cancer chemotherapy is still a serious challenge. Chemo-resistance and destructive side effects of chemotherapy drugs are the most critical limitations of chemotherapy. Chemo-resistance is the leading cause of chemotherapy failure. Chemo-resistance, which refers to the resistance of cancer cells to the anticancer effects of chemotherapy drugs, is caused by various reasons. Among the most important of these reasons is the increase in the efflux of chemotherapy drugs due to the rise in the expression and activity of ABC transporters, the weakening of apoptosis, and the strengthening of stemness. In the last decade, a significant number of studies focused on the application of nanotechnology in cancer treatment. Considering the anti-cancer properties of zinc, zinc oxide nanoparticles have received much attention in recent years. Some studies have indicated that zinc oxide nanoparticles can target the critical mechanisms of cancer chemo-resistance and enhance the effectiveness of chemotherapy drugs. These studies have shown that zinc oxide nanoparticles can reduce the activity of ABC transporters, increase DNA damage and apoptosis, and attenuate stemness in cancer cells, leading to enhanced chemo-sensitivity. Some other studies have also shown that zinc oxide nanoparticles in low doses can be helpful in minimizing the harmful side effects of chemotherapy drugs. In this article, after a brief overview of the mechanisms of chemo-resistance and anticancer effects of zinc, we will review all these studies in detail.

Design, Synthesis, and Anti-Leukemic Evaluation of a Series of Dianilinopyrimidines by Regulating the Ras/Raf/MEK/ERK and STAT3/c-Myc Pathways

Although the long-term survival rate for leukemia has made significant progress over the years with the development of chemotherapeutics, patients still suffer from relapse, leading to an unsatisfactory outcome. To discover the new effective anti-leukemia compounds, we synthesized a series of dianilinopyrimidines and evaluated the anti-leukemia activities of those compounds by using leukemia cell lines (HEL, Jurkat, and K562). The results showed that the dianilinopyrimidine analog H-120 predominantly displayed the highest cytotoxic potential in HEL cells. It remarkably induced apoptosis of HEL cells by activating the apoptosis-related proteins (cleaved caspase-3, cleaved caspase-9 and cleaved poly ADP-ribose polymerase (PARP)), increasing apoptosis protein Bad expression, and decreasing the expression of anti-apoptotic proteins (Bcl-2 and Bcl-xL). Furthermore, it induced cell cycle arrest in G2/M; concomitantly, we observed the activation of p53 and a reduction in phosphorylated cell division cycle 25C (p-CDC25C) / Cyclin B1 levels in treated cells. Additionally, the mechanism study revealed that H-120 decreased these phosphorylated signal transducers and activators of transcription 3, rat sarcoma, phosphorylated cellular RAF proto-oncogene serine / threonine kinase, phosphorylated mitogen-activated protein kinase kinase, phosphorylated extracellular signal-regulated kinase, and cellular myelocytomatosis oncogene (p-STAT3, Ras, p-C-Raf, p-MEK, p-MRK, and c-Myc) protein levels in HEL cells. Using the cytoplasmic and nuclear proteins isolation assay, we found for the first time that H-120 can inhibit the activation of STAT3 and c-Myc and block STAT3 phosphorylation and dimerization. Moreover, H-120 treatment effectively inhibited the disease progression of erythroleukemia mice by promoting erythroid differentiation into the maturation of erythrocytes and activating the immune cells. Significantly, H-120 also improved liver function in erythroleukemia mice. Therefore, H-120 may be a potential chemotherapeutic drug for leukemia patients.

Zinc Oxide Nanoparticles Trigger Autophagy in the Human Multiple Myeloma Cell Line RPMI8226: an In Vitro Study

Multiple myeloma (MM) is a malignant clonal proliferative plasma cell tumor. Zinc oxide nanoparticles (ZnO NPs) are used for antibacterial and antitumor applications in the biomedical field. This study investigated the autophagy-induced effects of ZnO NPs on the MM cell line RPMI8226 and the underlying mechanism. After RPMI8226 cells were exposed to various concentrations of ZnO NPs, the cell survival rate, morphological changes, lactate dehydrogenase (LDH) levels, cell cycle arrest, and autophagic vacuoles were monitored. Moreover, we investigated the expression of Beclin 1 (Becn1), autophagy-related gene 5 (Atg5), and Atg12 at the mRNA and protein levels, as well as the level of light chain 3 (LC3). The results showed that ZnO NPs could effectively inhibit the proliferation and promote the death of RPMI8226 cells in vitro in a dose- and time-dependent manner. ZnO NPs increased LDH levels, enhanced monodansylcadaverine (MDC) fluorescence intensity, and induced cell cycle arrest at the G2/M phases in RPMI8226 cells. Moreover, ZnO NPs significantly increased the expression of Becn1, Atg5, and Atg12 at the mRNA and protein levels and stimulated the production of LC3. We further validated the results using the autophagy inhibitor 3-methyladenine (3‑MA). Overall, we observed that ZnO NPs can trigger autophagy signaling in RPMI8226 cells, which may be a potential therapeutic approach for MM.

Hederagenin suppresses ovarian cancer via targeting mitochondrial fission through dynamin-related protein 1

A triterpenoid isolated from the plant Hedera helix, hederagenin was discovered to have anti-cancer, anti-inflammatory, anti-depressant and anti-fibrosis properties both in vivo and in vitro. In this study, the relationship between mitochondrial fission and hederagenin-induced apoptosis in ovarian cancer (OC) was investigated and the underlying mechanisms were deciphered. Hederagenin's cytotoxicity on OC cells was analyzed using colony formation and CCK-8 assays. The effect of hederagenin on OC cells was also verified by a mouse xenograft tumor model. Flow cytometric analysis was conducted to examine hederagenin's effects on mitochondrial membrane potential, apoptosis, and cell cycle OC cells. MitoTracker Red (CMXRos) staining was performed to observe the mitochondrial morphology. The protein levels of Bak, Bcl-2, Caspase 3, Caspase 9, Cyclin D1 and Bax were measured by Western blot. This study found that hederagenin could suppress the in vivo and in vitro SKOV3 and A2780 cell proliferation in an effective manner. Besides, hederagenin altered the mitochondrial membrane potential, induced S-phase and G0/G1-phase arrest, mitochondrial morphology changes, and apoptosis in OC cells. Additionally, our findings further demonstrated that hederagenin changed the mitochondrial morphology by suppressing dynamin-related protein 1 (Drp1), a crucial mitochondrial division factor. Moreover, Drp1 overexpression could reverse hederagenin-induced apoptosis, whereas the Drp1 knockdown had the opposite effect. Furthermore, hederagenin may trigger BAX mitochondrial translocation and apoptosis in OC cells. These results provided a novel perspective on the relationship between the modulation of mitochondrial morphology and the suppression of ovarian cancer by hederagenin.

Mitochondrial Dynamics in Neurodegenerative Diseases: Unraveling the Role of Fusion and Fission Processes

Neurodegenerative diseases (NDs) are a diverse group of disorders characterized by the progressive degeneration and death of neurons, leading to a range of neurological symptoms. Despite the heterogeneity of these conditions, a common denominator is the implication of mitochondrial dysfunction in their pathogenesis. Mitochondria play a crucial role in creating biomolecules, providing energy through adenosine triphosphate (ATP) generated by oxidative phosphorylation (OXPHOS), and producing reactive oxygen species (ROS). When they're not functioning correctly, becoming fragmented and losing their membrane potential, they contribute to these diseases. In this review, we explore how mitochondria fuse and undergo fission, especially in the context of NDs. We discuss the genetic and protein mutations linked to these diseases and how they impact mitochondrial dynamics. We also look at the key regulatory proteins in fusion (MFN1, MFN2, and OPA1) and fission (DRP1 and FIS1), including their post-translational modifications. Furthermore, we highlight potential drugs that can influence mitochondrial dynamics. By unpacking these complex processes, we aim to direct research towards treatments that can improve life quality for people with these challenging conditions.

Zinc oxide nanoparticles induce toxicity in diffuse large B-cell lymphoma cell line U2932 via activating PINK1/Parkin-mediated mitophagy

Diffuse large B-cell lymphoma (DLBCL) is the most common type of lymphoma. Zinc oxide (ZnO) nanoparticles have excellent anti-tumor properties in the biomedical field. The present study aimed to explore the underlying mechanism by which ZnO nanoparticles induce toxicity in DLBCL cells (U2932) via the PINK1/Parkin-mediated mitophagy pathway. After U2932 cells were exposed to various concentrations of ZnO nanoparticles, the cell survival rate, reactive oxygen species (ROS) generation, cell cycle arrest, and changes in the expression of PINK1, Parkin, P62, and LC3 were monitored. Moreover, we investigated monodansylcadaverine (MDC) fluorescence intensity and autophagosome and further validated the results using the autophagy inhibitor 3-methyladenine (3-MA). The results showed that ZnO nanoparticles could effectively inhibit the proliferation of U2932 cells and induce cell cycle arrest at the G0/G1 phases. Moreover, ZnO nanoparticles significantly increased ROS production, MDC fluorescence intensity, autophagosome formation, and the expression of PINK1, Parkin, and LC3, and decreased the expression of P62 in U2932 cells. In contrast, the autophagy level was reduced after the intervention of the 3-MA. Overall, ZnO nanoparticles can trigger PINK1/Parkin-mediated mitophagy signaling in U2932 cells, which may be a potential therapeutic approach for DLBCL.