Apoptosis In Melanoma Cells Research Articles

In vitro effects of l-kynurenine and quinolinic acid on adhesion, migration and apoptosis in B16 F10 melanoma cells

IntroductionThe inhibition of melanoma adhesion through adhesion molecules, such as integrins and E-cadherin, may represent a promising strategy for managing melanoma metastasis. Compounds, namely l-kynurenine (L-kyn) and quinolinic acid (Quin), previously displayed anti-cancer effects at half-maximal inhibitory concentration (IC50) against B16 F10 melanoma cells in vitro. However, the role of these compounds in B16 F10 melanoma cell adhesion, migration and apoptosis remain unknown. MethodsPost-exposure to the compounds, flow cytometry was used to analyse the expression of very late antigen-5 (VLA-5), E-cadherin and cleaved caspase-3 in B16 F10 melanoma and RAW 264.7 murine macrophage cells. An adhesion assay was used to quantify the adhesion of both cell lines to vitronectin. A scratch migration assay was used to measure the possible inhibition of cell migration in B16 F10 cells in response to L-kyn and Quin. ResultsIn both B16 F10 and RAW 264.7 cells, neither L-kyn nor Quin induced significant effects on VLA-5 expression or cell adhesion to vitronectin. In B16 F10 cells, both L-kyn and Quin elevated E-cadherin expression and displayed a trend of suppressed migration. However, only L-kyn elevated E-cadherin in RAW 264.7 cells. L-kyn induced apoptosis by elevating cleaved caspase-3 expression in both cell lines. ConclusionL-kyn and Quin demonstrated promising antimetastatic effects in their ability to elevate E-cadherin expression and induce apoptosis in B16 F10 melanoma cells. However, these effects did not occur in response to vitronectin or VLA-5 integrin alterations. Furthermore, it cannot be excluded that L-kyn also induced apoptosis in RAW 264.7 cells. As such, these effects should be confirmed in additional control cell lines and substantiated with in vivo models.

Doramectin Induces Apoptosis in B16 Melanoma Cells.

Metastatic melanoma resists current pharmacological regimens that act through apoptosis. This indicates that therapies acting via non-apoptotic cell-death pathways could be pursued. Doramectin has shown promising results in another cancer of neural crest origin, neuroblastoma, through the inhibition of growth via autophagy. Our research hypothesis is that doramectin induces autophagy in B16F10 melanoma cells. Cells were treated with doramectin (15 uM) or a combination of both doramectin and a cell-death inhibitor, compared to untreated control cells (media), and then analyzed with MTT analysis. Likewise, MDC analysis was completed to detect autophagy involvement with doramectin treatment. Flow cytometry and TUNEL Assay were conducted to observe cell death-related effects. MTT analysis of doramectin-treated cells displayed a decrease in cell growth compared to control. Apoptotic morphology was prominent in melanoma cells treated with doramectin. Increased autophagy was not detected by fluorometric microscopic analysis. Flow cytometry analysis of doramectin-treated cells showed apoptosis as a major mode of cell death with some necrosis. Doramectin induces a novel cell-death mechanism in melanoma compared to other forms of cancer and should be studied as an effective anti-cancer agent for melanoma treatment.

VSIG-3/IGSF11 silencing in A2058 melanoma cells simultaneously suppresses melanoma progression and induces anti-tumoral cytokine profile in human T cells: In silico and in vitro study.

VISTA is a newly discovered immune checkpoint whose functional mechanisms have become increasingly important to study due to its brilliant results in cancer immunotherapy. Despite VSIG-3/IGSF11 being identified as an inhibitory ligand for VISTA with potential as a target for cancer immunotherapy, very little is known of its functions. This study aimed to conduct a detailed analysis of VSIG-3/IGSF11 in melanoma, as well as to study the effects of its silencing on melanoma cell line progression and human T cell functions. Online databases were used to investigate VSIG-3/IGSF11 expression, its relationships, and prognostic value in melanoma. Then, the effects of VSIG-3/IGSF11 silencing on proliferation, migration, cell cycle arrest, and apoptosis in A2058 melanoma cells were assessed using MTT, colony formation, wound healing, cell cycle, and Annexin-VFITC/PI assays, respectively. Finally, A2058 cells transfected with VSIG-3/IGSF11 siRNA were co-cultured with human T cells, and the expression levels of T cell cytokines were evaluated using qRT-PCR. VSIG-3/IGSF11 expression was significantly increased in melanoma patients and cell lines; however, no correlation was found between VSIG-3/IGSF11 expression levels and clinicopathological characteristics, survival, or immune cell infiltration. Following VSIG-3/IGSF11 silencing in A2058 cells, viability, proliferation, and migration rates were decreased, while apoptosis was increased. T cells co-cultured with VSIG-3/IGSF11 siRNA-transfected A2058 cells exhibited increased expression levels of IFN-γ and IL-12 and decreased expression levels of IL-10, TGF-β, and TNF-α. The inhibitory effect of VSIG-3/IGSF11 silencing on A2058 melanoma cell progression, along with the alteration of T cell cytokines towards a pro-inflammatory phenotype, suggests that VSIG-3/IGSF11 is primarily involved in melanoma progression and modulating immune responses. Therefore, it may be a valuable target for immunotherapy in melanoma patients.

Repurposing of Antidiarrheal Loperamide for Treating Melanoma by Inducing Cell Apoptosis and Cell Metastasis Suppression In vitro and In vivo.

Melanoma is the most common skin tumor worldwide and still lacks effective therapeutic agents in clinical practice. Repurposing of existing drugs for clinical tumor treatment is an attractive and effective strategy. Loperamide is a commonly used anti-diarrheal drug with excellent safety profiles. However, the affection and mechanism of loperamide in melanoma remain unknown. Herein, the potential anti-melanoma effects and mechanism of loperamide were investigated in vitro and in vivo. In the present study, we demonstrated that loperamide possessed a strong inhibition in cell viability and proliferation in melanoma using MTT, colony formation and EUD incorporation assays. Meanwhile, xenograft tumor models were established to investigate the anti-melanoma activity of loperamide in vivo. Moreover, the effects of loperamide on apoptosis in melanoma cells and potential mechanisms were explored by Annexin V-FITC apoptosis detection, cell cycle, mitochondrial membrane potential assay, reactive oxygen species level detection, and apoptosis-correlation proteins analysis. Furthermore, loperamide-suppressed melanoma metastasis was studied by migration and invasion assays. What's more, immunohistochemical and immunofluorescence staining assays were applied to demonstrate the mechanism of loperamide against melanoma in vivo. Finally, we performed the analysis of routine blood and blood biochemical, as well as hematoxylin- eosin (H&E) staining, in order to investigate the safety properties of loperamide. Loperamide could observably inhibit melanoma cell proliferation in vitro and in vivo. Meanwhile, loperamide induced melanoma cell apoptosis by accumulation of the sub-G1 cells population, enhancement of reactive oxygen species level, depletion of mitochondrial membrane potential, and apoptosis-related protein activation in vitro. Of note, apoptosis-inducing effects were also observed in vivo. Subsequently, loperamide markedly restrained melanoma cell migration and invasion in vitro and in vivo. Ultimately, loperamide was witnessed to have an amicable safety profile. These findings suggested that repurposing of loperamide might have great potential as a novel and safe alternative strategy to cure melanoma via inhibiting proliferation, inducing apoptosis and cell cycle arrest, and suppressing migration and invasion.

Essential Oil Extracted from Lippia sidoides Cham. (Verbenaceae) Induces Cell Cycle Arrest, Apoptosis, and Antimigratory Effects in Melanoma Cells.

Melanoma, the most aggressive form of skin cancer, poses a substantial global health threat with increasing incidence rates. Although novel targeted therapies have improved melanoma treatment, challenges persist due to poor response rates and drug resistance. Plant-derived compounds have been crucial in anticancer drug discovery, with many natural products demonstrating the ability to target molecular pathways involved in tumor development. In this study, the anti-melanoma potential of essential oil extracted from the aerial parts of Lippia sidoides Cham. (EO-LS), composed mainly by the monoterpene thymol (96%), was demonstrated. Obtained results demonstrated that EO-LS disrupted critical cancer hallmarks in A2058 melanoma cells harboring the BRAFV600E mutation. Specifically, EO-LS induced G1-phase cell cycle arrest and apoptosis, as assessed by annexin-V, caspase-3 activity, and TUNEL assays. EO-LS also inhibited cell migration and disrupted the AKT signaling pathway, which is a critical regulator of melanoma progression. Furthermore, a dose-dependent increase in reactive oxygen species (ROS) generation was observed, indicating pro-oxidant properties. These findings highlighted the significant in vitro anticancer properties of EO-LS suggesting its potential as a promising molecular scaffold for developing of novel anti-melanoma candidates.

Evaluating the Diverse Anticancer Effects of Laos Kaempferia parviflora (Black Ginger) on Human Melanoma Cell Lines.

Cancer has become a consistent concern globally and increasingly fatal. Malignant melanoma is a rising concern, with its increased mortality. Kaempferia parviflora Wall. ex Baker (K. parviflora (KP)), commonly known as black ginger, is well known for its medicinal contributions. For the first time, in the following study we investigated the antimelanoma potential of Laos KP extracts in human cell lines. KP extracts (KPE) in methanol, DCM, and ethyl acetate showed strong cell inhibition in both melanomas, with KPE-DCM being particularly effective in inhibiting melanoma cell migration, invasion, and proliferation by inducing cell cycle arrest and apoptosis, while KPE-Hexane exhibited a low cell inhibition rate and a more limited effect. KPE affected the increased expression of caspase-3, PARP andBax and the decreased expression of the BcL-2, Mu-2-related death-inducing gene (MUDENG, MuD) protein. Furthermore, KPE enhanced apoptotic cells in the absence and presence of the pancaspase inhibitor Z-VAD-FMK. Interestingly, these apoptotic cells were significantly suppressed by the caspase inhibitor. Moreover, elevated mitochondrial membrane potential (MMP) and intracellular reactive oxygen species (ROS) levels, suggestive of KPE's mitochondrial-mediated apoptosis in melanoma cells, were also confirmed. KPE treatment increased MMP levels, and upregulated the generation of ROS in A375 cells but not in A2058 cells. However, pretreatment with an ROS scavenger (NAC) suppressed KPE-induced cell death and ROS generation. These results clearly pointed out KPE-induced mitochondrial-mediated apoptotic cell death as the mechanism behind the inhibition of the human melanoma cells. Future studies exploring the role of specific ROS sources and their interaction with mitochondrial dynamics could deepen the existing understanding on KPE-induced apoptosis.

Editorial Expression of Concern: A sphingolipid rich lipid fraction isolated from attenuated Leishmania donovani promastigote induces apoptosis in mouse and human melanoma cells in vitro

Editorial Expression of Concern: A sphingolipid rich lipid fraction isolated from attenuated Leishmania donovani promastigote induces apoptosis in mouse and human melanoma cells in vitro

Peptide Degrader-Based Targeting of METTL3/14 Improves Immunotherapy Response in Cutaneous Melanoma.

METTL3 has emerged as a promising therapeutic target in cancer treatment, although its oncogenic functions in melanoma development and potential for therapeutic targeting drug have not been fully explored. In this study, we define the oncogenic role of METTL3 in melanoma development and progression. Building on this insight, we examine our recently designed peptide inhibitor RM3, which targets the binding interface of METTL3/14 complex for disruption and subsequent ubiquitin-mediated proteasomal degradation via the E3 ligase STUB1. RM3 treatment reduces proliferation, migration, and invasion, and induces apoptosis in melanoma cells in vitro and in vivo. Subsequent transcriptomic analysis identified changes in immuno-related genes following RM3-mediated suppression of METTL3/14 N6-methyladenosine (m6A) methyltransferase activity, suggesting a potential for interaction with immunotherapy. A combination treatment of RM3 with anti-PD-1 antibody results in significantly higher beneficial tumor response in vivo, with a good safety profile. Collectively, these findings not only delineate the oncogenic role of METTL3 in melanoma but also showcase RM3, acting as a peptide degrader, as a novel and promising strategy for melanoma treatment.

Rosmarinic acid modulates purinergic signaling and induces apoptosis in melanoma cells.

Cancer cases have increased worldwide. Cutaneous melanoma (CM), a highly metastatic skin cancer, largely contributes to global statistical cancer death data. Research has shown that rosmarinic acid (RA) is a promising phenolic compound with antineoplastic properties. Thus, we investigated the effects of RA on apoptosis-inducing in melanoma cells, purinergic signaling modulation, and cytokine levels. We treated SK-MEL-28 cells for 24h with different concentrations of RA and assessed the apoptosis, CD39, CD73, and A2A expression, and cytokine levels. We found RA-induced apoptosis in melanoma cells. Regarding the purinergic system, we verified that RA downregulated the expression of CD73 and A2A, specially at high concentrations of treatment. Additionally, RA increased IL-6, IL-4, IL-10, IFN-γ, and TNF-α levels. Our in vitro results confirm RA's potential to be used to induce melanoma cell apoptosis, having CD73 and A2A as targets when reversion of immune suppression is desired. Further studies in animal models and clinical trials focusing on RA's modulation of purinergic signaling in melanoma are required.

Marizomib (Salinosporamide A) Promotes Apoptosis in A375 and G361 Melanoma Cancer Cells.

Malignant melanoma-a tumor originating from melanocytes-is characterized by dynamic growth and frequent metastases in the early stage of development. Current therapy methods are still insufficient, and there is a need to search for new ways of treating this malady. The induction of apoptosis-physiological cell death-by proteasome inhibitors is recognized as an effective method of non-invasive elimination of cancer cells. In our research, we wanted to check the potential of marizomib (MZB, salinosporamide A, NPI-0052)-an irreversible proteasome inhibitor derived from the marine actinomycete Salinispora tropica-to induce apoptosis in A375 and G361 malignant melanoma cells. We determined the cytotoxic activity of marizomib by performing an MTT test. Ethidium bromide and acridine orange staining demonstrated the disruption of membrane integrity in the examined cell lines. We confirmed the proapoptotic activity of marizomib by flow cytometry with the use of an FITC-Annexin V assay. A Western blot analysis presented an increase in the expression of proteins related to endoplasmic reticulum (ER) stress as well as markers of the apoptosis. The gathered findings suggest that marizomib induced the ER stress in the examined melanoma cancer cells and directed them towards the apoptosis pathway.

NUAK2 mediated regulation of Schwann Cell proliferation and migration in peripheral nerve injury via YAP

NUAK2 is a member of the AMP-activated protein kinase (AMPK) family, which plays an essential role in cellular processes such as apoptosis, proliferation, and cell fate. Recent studies have already shown that silencing of NUAK2 blocks proliferation and promotes apoptosis of human melanoma cells and liver cancer cells. In addition, NUAK2 is involved in the development of glioblastoma via regulating the expression of cancer stem cell-related genes, and it promotes the cell cycle entry in the glioblastoma cells. However, the expression and the role of NUAK2 in the progress of peripheral nerve regeneration after injury are yet to be elucidated. We observed that NUAK2 was upregulated following distal sciatic nerve crush (SNC). Interestingly, we discovered that NUAK2 showed co-localization with S100 (Schwann cell marker). Furthermore, we found that the NUAK2 had a spatiotemporal protein expression, which was consistent with proliferating cell nuclear-antigen (PCNA). The protein level of NUAK2 and YAP was upregulated in the model of TNF-α-induced Schwann cell (SC) proliferation. Furthermore, flow cytometry analysis, CCK-8, transwell assays, and wound healing assays were all performed with the purpose of exploring the role of NUAK2 in the regulation of SC proliferation and migration. More importantly, we found that NUAK2-deficient SCs showed significantly reduced expression of Yes-associated protein (YAP). Bioinformatic analysis identified upstream regulators of NUAK2 and NUAK2-associated genes (e.g., YAP1). Finally, we investigated the recovery changes during regeneration progress through the walking track analysis. Thus, we speculated that NUAK2 was involved in biochemical and physiological responses of SCs after SNC via YAP-driven proliferation and migration, and this study determined the importance of NUAK2 as a potential target in peripheral nerve regeneration.

BET Bromodomain Inhibition Potentiates Ocular Melanoma Therapy by Inducing Cell Cycle Arrest.

Ocular melanoma is a common primary malignant ocular tumor in adults with limited effective treatments. Epigenetic regulation plays an important role in tumor development. The switching/sucrose nonfermentation (SWI/SNF) chromatin remodeling complex and bromodomain and extraterminal domain family proteins are epigenetic regulators involved in several cancers. We aimed to screen a candidate small molecule inhibitor targeting these regulators and investigate its effect and mechanism in ocular melanoma. We observed phenotypes caused by knockdown of the corresponding gene and synergistic effects with BRD inhibitor treatment and SWI/SNF complex knockdown. The effect of JQ-1 on ocular melanoma cell cycle and apoptosis was analyzed with flow cytometry. Via RNA sequencing, we also explored the mechanism of BRD4. The best tumor inhibitory effect was observed for the BRD4 inhibitor (JQ-1), although there were no statistically obvious changes in the shBRD4 and shBRD9 groups. Interestingly, the inhibitory effect of JQ-1 was decrease in the shBRD4 group. JQ-1 inhibits the growth of melanoma in various cell lines and in tumor-bearing mice. We found 17 of these 28 common differentially expressed genes were downregulated after MEL270 and MEL290 cells treated with JQ-1. Four of these 17 genes, TP53I11, SH2D5, SEMA5A, and MDGA1, were positively correlated with BRD4. In TCGA database, low expression of TP53I11, SH2D5, SEMA5A, and MDGA1 improved the overall survival rate of patients. Furthermore, the disease-free survival rate was increased in the groups with low expression of TP53I11, SH2D5, and SEMA5A. JQ-1 may act downstream of BRD4 and suppress ocular melanoma growth by inducing G1 cell cycle arrest.

악성 흑색종에서 CGM이 유도하는 세포자멸사와 상피간엽이행 억제 효과

Objectives: This study explored the effects of CGM treatment on malignant melanoma cells, specifically by focusing on its ability to induce apoptosis and alter the expression of proteins involved in epithelial-mesenchymal transition (EMT), a critical process in cancer metastasis. Methods: To assess cell viability and proliferation rates, at MTT assay and colony formation assay were performed. FACS analysis was conducted to confirm cell apoptosis, and JC-1 fluorescent staining was executed. An invasion assay was performed to observe cell invasiveness, and protein expression was validated by western blot analysis. Results: Our findings demonstrated that CGM treatment significantly induced apoptosis in malignant melanoma cells. Additionally, CGM treatment markedly reduced the invasiveness of melanoma cells, as observed in the invasion assays. Western blot analysis revealed that CGM modulated the expression of several critical proteins involved in EMT, thereby disrupting the EMT process which is essential for cancer metastasis. Conclusions: The research findings indicate that CGM inhibits the growth of melanoma effectively induces apoptosis of cancer cells, and suppresses metastasis through EMT inhibition. Therefore, CGM demonstrates significant value as a potential cancer therapeutic agent.

Hyaluronic Acid-Coated Silica Nanoparticles for Targeted Delivery of Nitric Oxide to Cancer Cells.

Drug resistance and off-target toxicity are two of the greatest challenges to chemotherapeutic melanoma treatments. Nitric oxide (NO) represents an attractive alternative to conventional therapeutics due to its numerous anticancer properties and low probability of engendering resistance. As NO is highly reactive, macromolecular NO donors are needed for the controlled and targeted delivery of NO for therapeutic applications. Herein, mesoporous silica nanoparticles (MSNs) coated with hyaluronic acid (HA) were developed as a NO delivery system to facilitate controlled delivery to cancer cells through both passive and active targeting via the enhanced permeation and retention effect and directed binding of HA with CD44 receptors, respectively. The aminosilane modification, HA concentration, and HA molecular weight were systematically evaluated to facilitate the MSN coating and NO loading. The hydrodynamic diameter and dispersity of the nanoparticles increased after HA coating due to the hydrophilic nature of HA, with greater increases observed at higher HA molecular weight. Lower starting concentrations of HA and aminosilanes with longer alkyl chains favored more efficient HA coating. Faster NO-release kinetics and lower NO payloads were observed for the HA-coated MSNs relative to uncoated MSNs. However, the localized delivery of NO to cancer cells through the active targeting conferred by HA increased levels of oxidative stress and induced mitochondria-mediated apoptosis in melanoma cells. Cytotoxicity was also evaluated against human dermal fibroblasts, with the use of 6 kDa HA-coated MSNs resulting in the greatest therapeutic indices. Enhanced internalization of HA-coated nanoparticles into melanoma cells versus uncoated nanoparticles was visualized with confocal microscopy and quantified by fluorescence spectroscopy. In total, HA-coated MSNs represent a promising NO delivery system for potential use as a chemotherapeutic for skin melanomas.

Biomedical Applications of Cold Atmospheric Plasma: Cancer Therapy and Virus Inactivation

Cold atmospheric plasma (CAP), known for its ability to generate Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS), has emerged as a promising tool in many biomedical applications, including cancer therapeutics and virus inactivation. In cancer therapy, ROS and RNS induced by plasma have been shown to selectively target cancer cells, triggering apoptosis and inhibiting tumor growth while sparing healthy cells. This selective cytotoxicity makes plasma an attractive option for localized cancer treatment with minimal side effects. Additionally, the antimicrobial properties of ROS and RNS make plasma an effective agent for virus inactivation. By connecting the dots between cancer therapy and virus disinfection, this review paper sheds light on the potential of plasma-generated ROS and RNS as versatile tools in medical applications, offering a dual benefit of targeted cancer treatment and effective virus control. Specifically, this review explores the effects of CAP treatment on B16 melanoma cells, assessing changes in cell viability, proliferation, apoptosis and oxidative stress response. Dichloroacetate (DCA), a mitochondrial modulator, has shown promise in inducing apoptosis in melanoma cells. However, its clinical use is limited by side effects related to its neurotoxicity and suspected carcinogenicity. The potential of CAP in enhancing the therapeutic efficacy of DCA on B16-F10 melanoma apoptosis is also explored. CAP therapeutics for other types of cancers are also explored in this review. Alongside its implications in oncology, CAP has gathered substantial attention for its extraordinary potential in neutralizing viruses. CAP’s exceptional precision in targeting viral envelopes, genetic material and structural components disrupts their integrity and vital functions. This orchestrated mechanism offers a swift and efficacious route to render viruses inactive, encompassing both enveloped and nonenveloped viral types. In parallel pursuit, this review examines CAP-generated reactive species’ proficiency in deactivating SARS-CoV-2 across various surfaces. The inquiry entails subjecting surfaces to CAP treatment, succeeded by quantifying viral load and scrutinizing viral integrity. The outcomes gleaned from these investigations provide pivotal insights into CAP’s potential as a robust surface disinfection strategy, poised to combat the propagation of viral transmission.

Effect of dose-rate on nitric oxide-induced apoptosis in A375 human melanoma cells

Purpose: To investigate the effect of dose-rate on nitric oxide (NO)-induced apoptosis in A375 human melanoma cells. Methods: The A375 cells were exposed to NO at a steady-state concentration of 7 μM, similar to the level estimated to occur in vivo in inflamed tissues, and delivered by diffusion through silastic tubing. Trypan blue dye exclusion assay was used to assess cell proliferation and viability. Cell cycle was studied by propidium iodide (PI) staining while Annexin V-FITC and PI assays were used to evaluate apoptosis. Western blotting assay was carried out to determine protein levels of p53, Bax, DR4, DR5, Fas (CD95), Procaspase 8, Procaspase 9 and Procaspase 3. Results: Viability of A375 cells was reduced by 22 % after 24 h leading to extensive apoptosis and cell cycle arrest following exposure to a cumulative dose of 3360 μM/min NO. Treatment with NO stimulated p53 and triggered mitochondrial apoptotic events by inducing conformational changes in Bax. Also, activation of caspase 9 and 3, DR4, DR5, Fas (CD95) and caspase 8 appeared to be mediated concurrently by death receptor processing and downstream caspases. Conclusion: Nitric oxide (NO) induces programmed cell death, thus indicating that it could serve as an effective inhibitor to halt the progression of melanoma or as an enhancer to improve therapeutic strategies for treatment.

Ibrutinib Modulates Proliferation, Migration, Mitochondrial Homeostasis, and Apoptosis in Melanoma Cells.

Ibrutinib, a tyrosine kinase inhibitor with a broad spectrum of action, has been successfully explored to treat hematological and solid cancers. Herein, we investigated the anti-cancer effect of Ibrutinib on melanoma cell lines. Cytotoxicity was evaluated using the MTT assay. Apoptosis, mitochondrial membrane potential, reactive oxygen species (ROS) production, cell proliferation, and cell cycle stages were determined by flow cytometry. LDH release and Caspase 3/7 activity were determined by colorimetric and luminescent assays, respectively. Cell migration was evaluated by wound scratch assay. Gene expression was determined by real-time PCR. Gene Ontology (GO) enrichment analysis of melanoma clinical samples was performed using the Database for Annotation, Visualization and Integrated Discovery (DAVID). MTT assays showed that Ibrutinib is toxic for MeWo, SK-MEL-28, and WM164 cells. The annexin V/PI staining, Caspase 3/7 activity, and LDH release in MeWo cells revealed that apoptosis is the primary mechanism of death caused by Ibrutinib. Corroborating such observation, we identified that Ibrutinib treatment impairs the mitochondrial membrane potential of such cells and significantly increases the transcriptional levels of the pro-apoptotic factors ATM, HRK, BAX, BAK, CASP3, and CASP8. Furthermore, Ibrutinib showed antimetastatic potential by inhibiting the migration of MeWo cells. Finally, we performed a functional enrichment analysis and identified that the differential expression of Ibrutinib-target molecules is associated with enrichment of apoptosis and necrosis pathways in melanoma samples. Taken together, our results clearly suggest that Ibrutinib can be successfully explored as an effective therapeutic approach for melanomas.

Susceptibility of Melanoma Cells to Targeted Therapy Correlates with Protection by Blood Neutrophils.

Elevated levels of peripheral blood and tumor tissue neutrophils are associated with poorer clinical response and therapy resistance in melanoma. The underlying mechanism and the role of neutrophils in targeted therapy is still not fully understood. Serum samples of patients with advanced melanoma were collected and neutrophil-associated serum markers were measured and correlated with response to targeted therapy. Blood neutrophils from healthy donors and patients with advanced melanoma were isolated, and their phenotypes, as well as their in vitro functions, were compared. In vitro functional tests were conducted through nonadherent cocultures with melanoma cells. Protection of melanoma cell lines by neutrophils was assessed under MAPK inhibition. Blood neutrophils from advanced melanoma patients exhibited lower CD16 expression compared to healthy donors. In vitro, both healthy-donor- and patient-derived neutrophils prevented melanoma cell apoptosis upon dual MAPK inhibition. The effect depended on cell-cell contact and melanoma cell susceptibility to treatment. Interference with protease activity of neutrophils prevented melanoma cell protection during treatment in cocultures. The negative correlation between neutrophils and melanoma outcomes seems to be linked to a protumoral function of neutrophils. In vitro, neutrophils exert a direct protective effect on melanoma cells during dual MAPK inhibition. This study further hints at a crucial role of neutrophil-related protease activity in protection.

Glycyrrhizic acid inhibits DNA damage repair and enhances cisplatin-induced apoptosis of melanoma cells.

This research was designed to prospect the mechanism and impact of glycyrrhizic acid (GA) on DNA damage repair and cisplatin (CP)-induced apoptosis of melanoma cells. First, human melanoma cell SK-MEL-28 was stimulated using GA for 24, 48, and 72 h. Then, the optimal treatment time and dosage were selected. After that, cell counting kit-8 (CCK-8) was employed for testing the cell viability, flow cytometry for the apoptosis, comet assay for the DNA damage of cells, and western blot for the cleaved-Caspase3, Caspase3, Bcl-2, and γH2AX protein expression levels. The experimental outcomes exhibited that as the GA concentration climbed up, the SK-MEL-28 cell viability dropped largely, while the apoptosis level raised significantly, especially at the concentration of 100 μm. In addition, compared with GA or CPtreatment only, CP combined with GA notably suppressed the viability of melanoma cells and promoted cell apoptosis at the cytological level. At the protein level, the combined treatment notably downregulated the Bcl-2 and Caspase3 expression levels, while significantly upregulated the cleaved-Caspase3 and γH2AX expression levels. Besides, CP + GA treatment promoted DNA damage at the DNA molecular level. Collectively, both GA and CP can inhibit DNA damage repair and enhance the apoptosis of SK-MEL-28 cells, and the synergistic treatment of both exhibits better efficacy.

Nebivolol, an antihypertensive agent, has new application in inhibiting melanoma.

Repurposing existing drugs for cancer therapy has become an important strategy because of its advantages, such as cost reduction, effect and safety. The present study was designed to investigate the antimelanoma effect and possible mechanisms of action of nebivolol, which is an approved and widely prescribed antihypertensive agent. In this study, we explored the effect of nebivolol on cell proliferation and cell activity in melanoma in vitro and the potential antimelanoma mechanism of nebivolol through a series of experiments, including the analysis of the effects with regard to cell apoptosis and metastasis. Furthermore, we evaluated the antimelanoma effect on xenograft tumor models and inspected the antimelanoma mechanism of nebivolol in vivo using immunohistochemical and immunofluorescence staining assays. As results in this work, in vitro , nebivolol possessed a strong activity for suppression proliferation and cell cycle arrest on melanoma. Moreover, nebivolol significantly induced cell apoptosis in melanoma through a mitochondrial-mediated endogenous apoptosis pathway. Additionally, nebivolol inhibited melanoma cell metastasis. More importantly, nebivolol exhibited significantly effective melanoma xenograft models in vivo , which related to the mechanism of apoptosis induction, proliferation inhibition, metastasis blocking and angiogenesis arrest. Overall, the data of the present study recommend that nebivolol holds great potential in application as a novel agent for the treatment of melanoma.