B16F10 Melanoma Research Articles

TPC1 regulates melanoma tumourigenesis via mTORC1 and TFEB

The major cause of death in cancer patients is a combination of metastatic dissemination combined with therapy resistance. Over recent years, intratumour phenotypic heterogeneity arising from the bi-directional interplay between plastic cancer cells and the microenvironment has been identified as key to disease progression. Most notably metastatic outgrowth and resistance to targeted therapies are frequently associated with activity of mTORC1, a key metabolic hub that promotes protein synthesis and proliferation in the presence of nutrients. Yet while the regulation of mTORC1 by amino acids and glucose availability is well characterized, whether other mechanisms are important in controlling mTORC1 and its downstream signalling is less well understood. Here we show, using the murine B16-F0 melanoma cell line as a model, that mTORC1 activity is decreased following the knockout (KO) of TPC1, a cation channel localised to early and recycling endosomes. Consequently, TPC1 KO melanoma cells exhibit reduced proliferation and invasiveness, as well as increased pigmentation associated with nuclear localisation of the MITF-related transcription factor TFEB. Our results demonstrate that the knockout of TPC1 has induced significant tumour-suppressive effects in melanoma, during which the altered activity of mTORC1 and TFEB play the key roles. The results help us further understand the link between mTORC1 and endolysosomal ion channels, and reveal that TPC1 controls melanoma progression and represents a potential therapeutic target.

Dendritic Cell-Targeted Nanoparticles Enhance T Cell Activation and Antitumor Immune Responses by Boosting Antigen Presentation and Blocking PD-L1 Pathways.

Dendritic cells (DCs) within the tumor microenvironment (TME) have an insufficient capacity to activate T cells through antigen presentation. Furthermore, the programmed cell-death ligand 1 (PD-L1), abundantly expressed on tumor-associated DCs, binds the programmed cell-death 1 (PD-1)-positive T cells and suppresses their immune function. The binding of PD-L1 to CD80 (B7.1) on the same DC via cis-interactions further prevents T cell costimulation through CD28. Here, we present a strategy to simultaneously promote antigen cross-presentation and block the inhibitory interactions of PD-L1 on DCs to amplify T cell-mediated antitumor responses within the TME. Mesoporous silica nanoparticles (MSNPs) were loaded with clotrimazole (CLT) to boost MHC II-mediated antigen presentation by DCs, surface-modified with mannose to target CD206 on DCs, and then decorated with PD-L1 binding peptide (PDL1bp) to block PD-L1-mediated interactions. PDL1bp was cleaved from the mannosylated and CLT-loaded MSNPs (MSNP-MaN/CLT) under conditions simulating the TME and tethered to PD-L1 to reverse CD80 sequestration on DC2.4 cells. The blocking of PD-L1 by PDL1bp-decorated NPs (MSNP-MaN-PDL1bp) increased the cellular interactions between DC2.4 and EL4 T cells and the amount of IL-2 secretion. The MSNP-MaN/CLT were taken up rapidly by DC2.4 cells, promoted MHC II presentation of hen egg lysozyme (HEL), and increased IL-2 production from HEL antigen-primed 3A9 T cells, which was further enhanced by PDL1bp. In vivo investigation revealed that administration of the CLT-loaded and PDL1bp-functionalized MSNPs remarkably inhibited subcutaneous B16-F10 melanoma tumor growth when compared with anti-PD-L1 therapy. MSNP-MaN-PDL1bp/CLT treatment upregulated the levels of effector molecules such as granzyme B and proinflammatory cytokines (IFNγ and INFα) in the tumor tissue, indicating antitumoral T cell responses. This strategy of utilizing nanoparticles to trigger DC activation while promoting T cell stimulation can be used to amplify the antitumor T cell responses and represents a promising alternative to anti-PD-L1 immunotherapy.

Cholinergic Signaling Mediated by Muscarinic Receptors Triggers the Ultraviolet-Induced Release of Melanosome in Cultured Melanoma Cells.

In skin, melanin is synthesized and stored in melanosomes. In epidermal melanocytes, melanosomes are transported to and internalized by the neighboring keratinocytes, subsequently leading to skin pigmentation. Ultraviolet (UV) radiation induces the release of acetylcholine (ACh) from keratinocytes, which in turn activates ACh receptors (AChRs) on nearby melanocytes, forming a proposed "skin synapse". Here, we illustrated that the UV-induced melanosome release from cultured B16F10 melanoma cells could be mediated by co-actions of ACh. In the cell cultures, UV exposure robustly elicited melanosome release. Applied bethanechol (BeCh), an agonist of muscarinic AChR (mAChR), could significantly enhance the release. In parallel, the intracellular Ca2+ mobilization was regulated. The applied antagonists of M1 and/or M3 mAChRs could block the UV-induced melanosome release and the mobilization of intracellular Ca2+. The phosphorylation of PKC, triggered by UV and BeCh treatments, could be suppressed by the applied mAChR antagonists. The expressions of tethering complex for exocytosis, for example, Sec8, Exo70, and Rab11b, as well as synaptotagmin, were increased under UV exposure together with mAChR agonist: The inductions were fully abolished by M1 or M3 antagonist. Here, we hypothesize that the cholinergic signaling is playing roles in UV-induced exocytosis of melanosomes.

1-Acetyl-β-Carboline from a Jeju Gotjawal Strain Lentzea sp. JNUCC 0626 and Its Melanogenic Stimulating Activity in B16F10 Melanoma Cells.

The genus Lentzea is a prolific source of bioactive and structurally diverse secondary metabolites. We isolated a novel strain, Lentzea sp. JNUCC 0626, from Hwasun Gotjawal on Jeju Island, Korea. Based on 16S rRNA partial gene sequence analysis, strain JNUCC 0626 is closely related to Lentzea isolaginshaensis NX62 (99.41% similarity), Lentzea pudingi DHS C021 (99.31%), and Lentzea cavernae SYSU K10001 (99.26%). From the fermentation broth of JNUCC 0626, we isolated 1-acetyl-β-carboline, whose structure was established using IR, HR-ESI-MS, and 1D- and 2D-NMR techniques. 1-acetyl-β-carboline was found to activate melanogenesis in mouse B16F10 cells without cytotoxicity at concentrations up to 50 μM. At this concentration, the compound increased melanin content by 27.44% and tyrosinase activity by 240.64% compared to the control, by upregulating key melanogenic enzymes, including tyrosinase, TRP-1, TRP-2, and microphthalmia-associated transcription factor (MITF), a central regulator of melanogenesis. In addition, 1-acetyl-β-carboline significantly inhibited ERK phosphorylation, reducing it by 20.79% at a concentration of 12.5 μM and by 25.63% at 25 μM. This inhibition supports the hypothesis that 1-acetyl-β-carboline enhances melanin synthesis by upregulating MITF and melanogenic enzymes via the ERK signaling pathway. This study aimed to isolate and identify 1-acetyl-β-carboline from a novel strain of Lentzea sp. JNUCC 0626, discovered in Gotjawal, Jeju Island, and to evaluate its effect on melanin production in B16F10 melanoma cells. Skin irritation tests on 32 subjects confirmed its safety for topical use, and the findings suggest that 1-acetyl-β-carboline, which enhances melanogenesis without cytotoxicity, holds promise as a therapeutic agent for hypopigmentation-related conditions or as a cosmetic ingredient.

Cytoglobin attenuates melanoma malignancy but protects melanoma cells from ferroptosis.

Cutaneous malignant melanoma is the most aggressive and the deadliest form of skin cancer. There are two types of limitations which universally exist in current melanoma therapy: Adverse effects and reduced efficiency. Cytoglobin (CYGB), an iron hexacoordinated globin, is highly enriched in melanocytes and frequently epigenetically silenced during melanoma genesis. The present study aimed to explore its potential role as a biomarker for ferroptosis treatment. It was observed that B16F10 and A375 melanoma cells with loss of CYGB expression were highly sensitive to ferroptosis inducers RSL3 and erastin, whereas G361 melanoma cells with highly enriched CYGB were resistant to RSL3 or erastin. Ectopically overexpressed CYGB rendered B16F10 and A375 cells resistant to RSL3 or erastin, accompanied by decreased proliferation and epithelial‑mesenchymal transition (EMT). By contrast, knockdown of CYGB expression made G361 cells sensitive to ferroptosis induction but induced proliferation and EMT progression of G361 cells. Mechanistically, CYGB‑induced resistance of melanoma cells to ferroptosis may have been associated, in part, with i) Suppression of EMT; ii) upregulation of glutathione peroxidase 4 expression; iii) decrease of labile iron pool. In vivo study also demonstrated that CYGB overexpression rendered xenograft melanoma much more resist to RSL3 treatment. Based on these findings, CYGB is a potential therapeutic biomarker to screen the melanoma patients who are most likely benefit from ferroptosis treatment.

Interdependency and differential expression of ERK1 and ERK2 in breast and melanoma cell lines

BackgroundRegulatory mechanism of ERK1 and ERK2, their mechanisms of action, and how they impact on development, growth, and homeostasis of different organisms have been given much emphasis for long. ERK1 and 2 though are isoforms of ERK mitogen-activated protein kinase but are coded by two different genes MAPK3 and MAPK1 respectively and show differential expressions and interdependency in different cancer cell lines. Our previous investigations substantially stated the effect of ERK1 and ERK2 on different extracellular molecules like MMPs and integrins, responsible for cell growth and differentiation. Here, we aim to study individual roles of ERK1 and ERK2 and their interdependency in progression and invasiveness in various cancer cell lines.MethodsDifferent cancer cell lines namely B16F10 (melanoma), MCF7, and MDAMB231 (breast cancer) for studying this particular question were used. Methodologies like gelatin zymography, immunoprecipitation, Western blotting, cell invasion assay, wound healing assay, siRNA transfection, and double transfection procedures were followed for our study.ResultsOur findings suggest compensation for ERK2 deficiency by pERK1, clear ERK2 predominance in MCF7 cell line, ERK1-ERK2 interdependency in MDAMB231 cells with regard to compensating each other, and significant role of both ERK1 and ERK2 in modulation of MMP9.ConclusionIf summarized, our results prove the contribution of ERK2 in compensating ERK1 loss and vice versa and an evident role of ERK1 in cancer cell invasiveness.

Optimization, isolation, identification and molecular mechanisms in B16F10 melanoma cells of a novel tyrosinase inhibitory peptide derived from split gill mushrooms

Hyperpigmentation often arises from an imbalance in melanogenesis, primarily due to the overexpression of tyrosinase (TYR). While the inhibition of TYR presents a common approach to skin whitening, it can lead to undesirable side effects. Thus, there is growing interest in safe and natural alternatives for TYR inhibition. Bioactive compounds and peptides sourced from split gill mushrooms hold promise in this regard. This study aims to optimize the conditions for papain-mediated hydrolysis of split gill mushroom protein to inhibit TYR activity, utilizing response surface methodology (RSM) and central composite design (CCD). Optimal conditions were determined at a temperature of 46.70 °C, a hydrolysis time of 217.09 min, and an enzyme-to-substrate ratio (E/S) of 1.1%. Under these conditions, the resulting hydrolysates exhibited significant TYR inhibition, with an IC50 value of 117.86 μg/mL and a degree of hydrolysis (DH) of 87.97%. Further purification via ultrafiltration and RP-HPLC yielded a peptide, Tyr-Ala-Ser-Ile-Leu-Leu (YASILL or YL-6), identified through LC-Q-TOF-MS/MS, which competitively inhibited TYR. YL-6 demonstrated an IC50 value of 3.97 mM for mono-phenolase activity and 6.75 mM for di-phenolase activity. Molecular docking analysis revealed hydrogen bonds and hydrophobic interactions between TYR and YL-6. Treatment of B16F10 cells with YL-6 across concentrations ranging from 10-3000 μM showed no cytotoxic effects.The inhibition of melanin synthesis was investigated via qRT-PCR along with Western blot in MITF, TYR, TRP-1, and TRP-2. The results obtained in this research may prove significant in guiding the development of commercially viable cosmetic products to whiten the skin.

Cryoablation Does Not Significantly Contribute to Systemic Effector Immune Responses in a Poorly Immunogenic B16F10 Melanoma Model.

Cryoablation is a minimally invasive procedure implemented to destroy solid tumors. It also results in the release of tumor antigens into the systemic circulation. Preclinical studies using immunogenic tumor models have shown that cryoablation evokes antitumor immune responses. The mechanisms by which cryoablation impacts immune responses in poorly immunogenic tumors have not been sufficiently explored. We used a bilateral B16F10 melanoma model devoid of strong immunogenic antigens. Cryoablation-induced effector immune responses were investigated, also in combination with a peritumoral STING agonist and systemic anti-PD-1. Selective immune cell depletion, T-cell migration arrest, in vivo T-cell transplantation, and cryoablation versus surgical removal techniques were used to determine the contribution of cryoablation and immunotherapies to systemic antitumor effector immune responses. Treatment of a tumor with cryoablation + STING agonist + anti-PD-1 resulted in the rejection of unablated, contralateral tumors. Depletion studies demonstrated that tumor rejection is essentially dependent on CD8+ T cells. T-cell arrest in the lymph nodes had no effect on the rejection process. Splenic CD8+ T cells isolated from cryoablation-treated mice with B16F10 melanoma, upon transplantation into melanoma-bearing recipients, did not impact the recipient's tumor growth. Finally, comparison of cryoablation + STING agonist + anti-PD-1 versus surgery + STING agonist + anti-PD-1 in the bilateral tumor model showed no difference in the rejection of contralateral tumors. Cryoablation does not significantly contribute to systemic antitumor effector immune responses in a B16F10 melanoma model. Cryoablation primarily performs tumor debulking, and immunotherapy functions independently of cryoablation in eliciting antitumor effector immune responses.

Hydrogel based on M1 macrophage lysate and alginate loading with oxaliplatin for effective immunomodulation to inhibit melanoma progression, recurrence and metastasis

Despite the monumental success of immunotherapy in treating melanoma clinically, it still confronts significant challenges, chiefly that singular immunomodulatory tactics are insufficient to suppress the recurrence and metastasis of melanoma. Herein, these challenges are addressed by a hydrogel based on M1 macrophage lysate and alginate (M1LMHA) loaded with oxaliplatin (OXA), named M1LMHA@OXA.The results obtained from scanning electron microscopy and confocal microscopy indicate that the structure and morphology of M1LMHA@OXA remain unchanged. Flow cytometry results reveal that M1LMHA@OXA significantly promotes the maturation of dendritic cells (DCs) and enhances the proliferation of T lymphocytes. In a subcutaneous melanoma transplant model, M1LMHA@OXA effectively suppressed tumor growth in comparison to OXA alone and M1LMHA alone. Flow cytometry demonstrated that M1LMHA@OXA markedly increased the number of mature DCs and CD8+ T cells at the tumor site, while significantly reducing the quantity of M2-like tumor-associated macrophages (TAM) and enhancing the presence of M1 macrophages. Enzyme-linked immunosorbent assay (ELISA) results indicated that following treatment with M1LMHA@OXA, the levels of interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) in the bloodstream of mice were significantly elevated, whereas interleukin-10 (IL-10) exhibited no significant difference. This outcome further corroborates the ability of M1LMHA@OXA to substantially bolster the immune capability of mice. Similar results have also been observed in a melanoma subcutaneous transplantation recurrence model, and optical imaging of the lungs of mice revealed that M1LMHA@OXA inhibited tumor metastasis to the lungs. Notably, M1LMHA@OXA exhibits an exceptional therapeutic effect on the growth, post-surgical recurrence, and metastasis of the B16F10 melanoma. Therefore, this study provides a straightforward strategy that leverages the cooperative regulation of multiple immune cells to thwart the proliferation, recurrence, and spread of melanoma.

Effect of combined blue light and 5-ALA on mitochondrial functions and cellular responses in B16F1 melanoma and HaCaT cells.

The online version contains supplementary material available at 10.1007/s10616-024-00654-x.

A TCM formula assists temozolomide in anti-melanoma therapy by suppressing the STAT3 signaling pathway

Ethnopharmacological relevanceTemozolomide (TMZ) is a first-line therapeutic medication for melanoma. Nonetheless, it exhibits a relatively elevated toxicity profile, and falls short in terms of both effectiveness and median survival rate. Clinical research has demonstrated that the integration of traditional Chinese medicine (TCM) with chemotherapy in the treatment of melanoma can enhance efficacy and reduce toxicity. A TCM formula (SLE) containing Lonicera japonica Thunb. and Robinia pseudoacacia L. has shown anti-melanoma properties through the inhibition of STAT3 phosphorylation. In the genesis and advancement of melanoma, the STAT3 signaling pathway is essential. Aim of the studyThe aim of this study was to evaluate the effect of SLE combined with TMZ (SLE/TMZ) in inhibiting melanoma, and to explore the contribution of inhibiting the STAT3 signaling pathway in this effect. Materials and methodsBoth A375 cells and B16F10 tumor-bearing mice were used for in vitro and in vivo experiments, respectively. In vitro assays included CCK8, crystal violet staining, flow cytometry, qRT-PCR, and Western blotting. Animal experiment indicators included tumor volume, tumor weight, mouse weight, and the proportion of mouse immune cells. ResultsSLE/TMZ inhibited the proliferation and growth of A375 cells, and also induced apoptosis. Additionally, SLE/TMZ synergistically inhibited tumor growth in the B16F10 melanoma mouse model and had immunomodulatory effects, increasing the proportion of Th, Tc, and NK cells and decreasing the proportion of MDSCs in the spleen of melanoma-bearing mice. qRT-PCR and Western blotting results confirmed that SLE/TMZ inhibited STAT3 phosphorylation and regulated its downstream factors, including Bcl2, Mcl1, CCND1, MYC, MMP2, MMP9, VEGFA, and FGF2. The inhibitory effect of SLE/TMZ on melanoma cell growth was considerably lessened when STAT3 was overexpressed at the cellular level. ConclusionSynergistic anti-melanoma effects of SLE/TMZ have been observed in animal and cellular models. One of the mechanisms of SLE/TMZ that underlies its anti-melanoma actions is inhibition of the STAT3 pathway. This work offers pre-clinical pharmacological backing for the advancement of SLE as a therapeutic agent to be used in conjunction with TMZ for the treatment of melanoma.

Anti-melanogenic effect of a novel oligosaccharide derived from almond on forskolin-stimulated melanogenesis in B16F10 melanoma cells

The application of natural products for regulating skin pigmentation is increasingly being acknowledged due to their security and proven efficacy. Almond (Amygdalus communis L.) is an edible nut plant with significant nutritional value and medicinal attributes. In this research, oligosaccharide (ACO-II-1) was extracted and isolated applying gel chromatography techniques from the aqueous extract of almond kernel. Structural characterization of ACO-II-1 was conducted using ESI-MS, methylation analysis and 1D/2D-NMR. The findings indicated that ACO-II-1 was composed of fructose and glucose and the glycosidic bond predominantly featured β-D-Fruf-(1 → 2)-β-D-Fru-(1 → 6)-α-D-Glcp-(1 → 1)-α-D-Glcp. Moreover, ACO-Ⅱ-1 possessed strong antioxidant activity and notable inhibitory effect on melanogenesis in forskolin (FSK)-induced B16F10 melanoma cells. Subsequent mechanism investigation was conducted and suggested that the anti-melanogenic properties of ACO-Ⅱ-1 might be attributed to its modulation of the Mitogen-activated protein kinases (MAPKs) and β-catenin signaling pathways. These results indicated that edible plant derived ACO-II-1 might be served as promising inhibitor of hyperpigmentation with potential application in pharmaceutical and skin-care sector.

Paulownin elicits anti-tumor effects by enhancing NK cell cytotoxicity through JNK pathway activation.

Paulownin, a natural compound derived from Paulownia tomentosa wood, exhibits various physiological functions, including anti-bacterial and anti-fungal effects. However, the impact of paulownin on natural killer (NK) cell immune activity remains largely unknown. In this study, we investigated the effect of paulownin on NK cell activity both in vitro and in vivo, and explored its potential mechanisms. NK-92 cells were used for in vitro experiments and a BALB/c mouse model with B16F10 cells injected subcutaneously were used for in vivo anti-tumor analysis. We found that paulownin enhanced the cytolytic activity of NK-92 cells against leukemia, human colon, and human lung cancer cell lines. Paulownin treatment increased the expression of the degranulation marker protein CD107a and cytolytic granules, including granzyme B and perforin in NK-92 cells. Moreover, these enhancements of cytotoxicity and the expression of cytolytic granules induced by paulownin were also observed in human primary NK cells. Signaling studies showed that paulownin promoted the phosphorylation of JNK. The increased perforin expression and elevated cytotoxic activity induced by paulownin were effectively inhibited by pre-treatment with a JNK inhibitor. In vivo studies demonstrated that the administration of paulownin suppressed the growth of B16F10 melanoma cells allografted into mice. Paulownin administration promoted the activation of NK cells in the spleen of mice, resulting in enhanced cytotoxicity against YAC-1 cells. Moreover, the anti-tumor effects of paulownin were reduced upon the depletion of NK cells. Therefore, these results suggest that paulownin enhances NK cell cytotoxicity by activating the JNK signaling pathway and provide significant implications for developing new strategies for cancer immunotherapy.

Liposome preparation of alpha-arbutin: stability and toxicity assessment using mouse B16F10 melanoma cells

ABSTRACT Melanoma is the most aggressive type of skin cancer, with few therapeutic alternatives following metastasis development. In recent years, drug delivery-associated nanotechnology has shown promising targeted results with diminished adverse effects compared to conventional treatments. This study aimed to (1) examine the effects of plant-derived α-arbutin, a natural compound and (2) compare these findings with bioactively developed liposomes containing α-arbutin utilizing the B16-F10 murine melanoma cell line as a model. Liposomes were obtained through reversed-phase evaporation by applying a spray dryer to assess their stability. The following biologic assays were measured cytotoxicity/antiproliferative (MTT, Neutral Red, and dsDNA PicoGreen). In addition, the levels of melanin and purinergic enzymes were also measured. The production of reactive oxygen species (ROS) and nitric oxide (NO) was determined as a measure of oxidative state. Treatment with nano-liposome containing alpha-arbutin induced a significant 68.4% cytotoxicity, similar to the positive control, in the B16-F10 murine melanoma cell line at 72 hr. Further, arbutin and liposomes containing alpha-arbutin increased levels of ROS and nitrite formation at 72 hr at the highest concentration (100 and 300 µg/ml) of treatments. Arbutin and liposomes containing alpha-arbutin reduced melanin levels at all tested concentrations. In addition, arbutin and alpha-arbutin containing liposomes lowered nucleotides (AMP, ADP, and ATP) and nucleoside (adenosine) levels in melanoma cells. Evidence suggests that α-arbutin containing liposome can be considered as an alternative immunosuppressive agent stimulated in melanoma treatment.

Abstract MP15: Macrophage PPARα is essential to increased immune function induced by angiotensin converting enzyme (ACE).

Mice with increased macrophage expression of angiotensin converting enzyme (ACE), called ACE 10/10 mice, have a profound increase of macrophage function in response to diverse immune challenges including tumors, infection, atherosclerosis, and Alzheimer’s disease. ACE 10/10 macrophages are highly efficient in oxidative ATP generation, and they express increased amounts of peroxisome proliferator-activated receptor alpha (PPARα), a transcription factor that controls lipid metabolism. To pinpoint the role of PPARα in increasing macrophage immune function, we used LysM-Cre-LoxP system to generate ACE 10/10 mice selectively lacking macrophage PPARα (A10-PPARα-Cre mice). This reduced macrophage fatty acid metabolism, reduced oxidative metabolism, and lowered macrophage intracellular ATP. Functionally, A10-PPARα-Cre macrophage are impaired in both adaptive and innate immunity. A10-PPARα-Cre mice have larger tumor growth of B16-F10 melanoma, less intratumor macrophages, reduced anti-tumor cytokines, and reduced generation of tumor antigen-specific CD8 + T cells. The mice also have a very attenuated anti-bacterial response to methicillin-resistant Staphylococcus aureus (MRSA) infection, with more severe MRSA tissue colonization in vivo . In addition, increasing ACE expression or adding a PPARα agonist to the human monocytic cell line THP-1 enhances tumor cell cytotoxicity, phagocytosis of bacteria, and bacterial killing. Thus, we find that elevated macrophage PPARα is absolutely required for the increased immunity of ACE 10/10 mice. This may indicate a pathway to increasing human immunity.

Novel embelin-loaded transniosomes for topical delivery: comprehensive exploration of in vitro, ex vivo and dermatokinetic assessment for anti-cancer activity.

This study systematically designed and optimised a transniosomal formulation containing embelin for skin cancer management. The transniosomes were developed using a rotary evaporation method and then optimised using a Box-Behnken design. The optimized embelin-loaded transniosomes (Opt-EMB-TNs) exhibited a vesicle size of 149.01 nm, polydispersity index of 0.184, a zeta potential of -21.14 mV, an entrapment efficiency of 75.6 ± 0.65%, drug loading of 3.36 ± 0.03% and drug release of 80.88 ± 2.55%. The antioxidant potential of Opt-EMB-TNs was found to be 88.54% when compared to standard ascorbic acid. Dermatokinetic studies showed a greater drug deposition in targeted skin areas with Opt-EMB-TN gel compared to the embelin conventional gel (EMB-CF gel). In addition, the penetration depth study of the skin sample revealed that the transniosomal gel containing rhodamine B dye exhibited higher penetration than that of the rhodamine B dye containing hydroalcoholic solution. The efficacy of Opt-EMB-TNs for skin cancer was confirmed by cytotoxicity assay against the B16F10 melanoma cell line. The study concluded that the Opt-EMB-TN gel formulation is a promising and effective topical treatment for skin cancer, demonstrating significant potential for further development and clinical application. © 2024 Society of Chemical Industry.

Nanoparticles targeting immune checkpoint protein VISTA induce potent antitumor immunity

BackgroundImmune checkpoint protein V-domain immunoglobulin suppressor of T cell activation (VISTA) controls antitumor immunity and is a valuable target for cancer immunotherapy. Previous mechanistic studies have indicated that VISTA impairs...

Discovery of novel thiophene[3,2-d]pyrimidine-based tubulin inhibitors with enhanced antitumor efficacy for combined use with anti-pd-l1 immunotherapy in melanoma

Herein, we designed and synthesized a series of novel 2-methylthieno [3,2-d]pyrimidine analogues as tubulin inhibitors with antiproliferative activities at low nanomolar levels. Among them, compound DPP-21 displayed the most potent anti-proliferative activity against six cancer cell lines with an average IC50 of ∼6.23 nM, better than that of colchicine (IC50 = 9.26 nM). DPP-21 exerted its anti-cancer activity by suppressing the polymerization of tubulin with an IC50 of 2.4 μM. Furthermore, the crystal structure of DPP-21 in complex with tubulin was solved by X-ray crystallography to 2.94 Å resolution, confirming the direct binding of DPP-21 to the colchicine site. Moreover, DPP-21 arrested the cell cycle in the G2/M phase of mitosis, subsequently inducing tumor cell apoptosis. Additionally, DPP-21 was able to effectively inhibit the migration of cancer cells. Besides, DPP-21 exhibited significant in vivo anti-tumor efficacy in a B16–F10 melanoma tumor model with a TGI of 63.3 % (7 mg/kg) by intraperitoneal (i.p.) injection. Notably, the combination of DPP-21 with NP-19 (a PD-L1-targeting small molecule inhibitor reported by our group before) demonstrated enhanced anti-cancer efficacy in vivo. These results suggest that DPP-21 is a promising lead compound deserving further investigation as a potential anti-cancer agent.

Auto-defense of skin and melanin regulation through glutathione reductase modulation: a new insight

Background: The present study is to understand the Siddha cosmetic preparation - Eve fresh skinbrite cream/herbal extracts used in the cream in down-regulating the melanogenesis process and upregulating glutathione activity to offer skin lightening benefit. Methods: The effect of certain herbal extracts or the combination in reducing tyrosinase activity and associated melanin formation was evaluated in B16F10 melanoma cells and also up regulating glutathione reductase activity leading to the conversion of a reduced form of glutathione (GSH) from GSSG. Results: The extract of Berberis aristata exhibited even activity in inhibiting both tyrosinase and melanin in B16F10 melanoma cell lines. The extract combination also showed a greater effect on increasing GR activity. Conclusions: The herbal ingredients individually and as a combination exhibited strong effects in reducing tyrosinase activity and also upregulating GR activity and thereby reducing skin pigmentation.

Grape seed phenolic extracts encapsulation in polymeric nanoparticles: Characterization and in vitro evaluation against skin melanoma

Nanocarrier platforms encapsulating plant-based natural extracts have emerged as an attractive tool to increase the safety and stability of phytomedicines and nutraceuticals. In this study, phenolic fractions were extracted from grape seed waste, spray dried, and characterized. Grape seed extracts (GSE) of Marselan, a red international variety, and Obeidi, a Lebanese autochthonous white variety, had a total phenolic content (TPC) of 301 and 206 mg gallic acid equivalents (GAE)/g of dry matter, respectively, along with a high content of catechins, gallic acid, epicatechins, caffeic acid, syringic acid, and protocatechuic acid. A nanocarrier formulation was developed using poly(ethylene glycol)-b-poly(lactide-co-glycolide) (PEG-PLGA), yielding GSE-loaded nanoparticles (NPs) with an average of 230 nm particle size and −35 mV zeta potential, 50% encapsulation efficiency, and sustained release over 96 h. GSE NPs exhibited high colloidal stability in terms of size and high chemical stability in terms of TPC and antioxidant activity for both Marselan and Obeidi when stored at 4 °C for 3 months. GSE NPs showed excellent biocompatibility in human dermal fibroblasts. Both NPs and crude extracts significantly suppressed the proliferation of B16–F10 melanoma cells, particularly Obeidi NPs. This study emphasizes the important role nanotechnology can play in the valorization of bioactive nutraceuticals by presenting GSE NPs as a promising nanoformulation against skin cancer.