Recent developments in nanomedicine for melanoma treatment

Development of nanoemulgel of 5-Fluorouracil for skin melanoma using glycyrrhizin as a penetration enhancer

The purpose of this study was to enhance the topical delivery of 5-Fluorouracil (5-FU), a cancer treatment, by developing a nanoemulgel formulation. Glycyrrhizin (GLY), a natural penetration enhancer has been investigated to exhibit synergistic effects with 5-FU in inhibiting melanoma cell proliferation and inducing apoptosis, Hence, GLY, along with suitable lipids was utilized to create an optimized nanoemulsion (NE) based gel. Solubility studies and ternary phase diagram revealed isopropyl myristate (IPM), Span 80, Tween 80 as Smix and Transcutol P as co-surfactant. IPM demonstrates excellent solubilizing properties facilitates higher drug loading, ensuring efficient delivery to the target site.,The optimized formulation consisting of 40 % IPM, 30 % of mixture of Tween80: Span80 (Smix) and 15 % Transcutol P provides with a nanometric size of 64.1 ± 5.13 nm and drug loading of 97.3 ± 5.83 %. The optimized formulation observed with no creaming and breakeing of NE and found thermodynamically stable during different stress conditions (temperatures of 4.0 °C and 45.0 °C) and physical thawing (-21.0 ± 0.50 °C to 20.0 ± 0.50 °C). The NE was then transformed into a nanoemulgel (NEG) using 1.5 % w/w Carbopol base and 0.1 % w/w glycyrrhizin. The ex vivo permeability studies showed significant enhancements in drug permeability with the GLY-based 5-FU-NEG formulation compared to pure 5-FU gel in excised pig skin upto1440 min in PBS 7.4 as receptor media. The IC50 values for Plain 5-FU gel, 5-FU-NEG, and GLY-based 5-FU-NEG were found to be 20 µg/mL, 1.1 µg/mL, and 0.1 µg/mL, respectively in B16F10 cell lines. The percentage intracellular uptake of GLY-5-FU-NEG and 5-FU-NEG was found to be 44.3 % and 53.6 %, respectively. GLY-based 5-FU-NEG formulation showed alterations in cell cycle distribution, in compared to 5-FU-NE gel. The overall findings suggest that the GLY-based 5-FU-NEG holds promise for improving anti-melanoma activity.

Application of organic nanocarriers for intraocular drug delivery

The application of intraocular drug delivery is usually limited due to special anatomical and physiological barriers, and the elimination mechanisms in the eye. Organic nano-drug delivery carriers exhibit excellent adhesion, permeability, targeted modification and controlled release abilities to overcome the obstacles and improve the efficiency of drug delivery and bioavailability. Solid lipid nanoparticles can entrap the active components in the lipid structure to improve the stability of drugs and reduce the production cost. Liposomes can transport hydrophobic or hydrophilic molecules, including small molecules, proteins and nucleic acids. Compared with linear macromolecules, dendrimers have a regular structure and well-defined molecular mass and size, which can precisely control the molecular shape and functional groups. Degradable polymer materials endow nano-delivery systems a variety of size, potential, morphology and other characteristics, which enable controlled release of drugs and are easy to modify with a variety of ligands and functional molecules. Organic biomimetic nanocarriers are highly optimized through evolution of natural particles, showing better biocompatibility and lower toxicity. In this article, we summarize the advantages of organic nanocarriers in overcoming multiple barriers and improving the bioavailability of drugs, and highlight the latest research progresses on the application of organic nanocarriers for treatment of ocular diseases.

Nanodelivery systems for cutaneous melanoma treatment

Cutaneous melanoma (CM) is a multifactorial disease whose treatment still presents challenges: the rapid progression to advanced CM, which leads to frequent recurrences even after surgical excision and, notably, the low response rates and resistance to the available therapies, particularly in the case of unresectable metastatic CM. Thereby, alternative innovative therapeutic approaches for CM continue to be searched. In this review we discuss relevant preclinical research studies, and provide a broad-brush analysis of patents and clinical trials which involve the application of nanotechnology-based delivery systems in CM therapy. Nanodelivery systems have been developed for the delivery of anticancer biomolecules to CM, which can be administered by different routes. Overall, nanosystems could promote technological advances in several therapeutic modalities and can be used in combinatorial therapies. Nevertheless, the results of these preclinical studies have not been translated to clinical applications. Thus, concerted and collaborative research studies involving basic, applied, translational, and clinical scientists need to be performed to allow the development of effective and safe nanomedicines to treat CM.

How to Treat Melanoma? The Current Status of Innovative Nanotechnological Strategies and the Role of Minimally Invasive Approaches like PTT and PDT

Melanoma is the most aggressive type of skin cancer, the incidence and mortality of which are increasing worldwide. Its extensive degree of heterogeneity has limited its response to existing therapies. For many years the therapeutic strategies were limited to surgery, radiotherapy, and chemotherapy. Fortunately, advances in knowledge have allowed the development of new therapeutic strategies. Despite the undoubted progress, alternative therapies are still under research. In this context, nanotechnology is also positioned as a strong and promising tool to develop nanosystems that act as drug carriers and/or light absorbents to potentially improve photothermal and photodynamic therapies outcomes. This review describes the latest advances in nanotechnology field in the treatment of melanoma from 2011 to 2022. The challenges in the translation of nanotechnology-based therapies to clinical applications are also discussed. To sum up, great progress has been made in the field of nanotechnology-based therapies, and our understanding in this field has greatly improved. Although few therapies based on nanoparticulate systems have advanced to clinical trials, it is expected that a large number will come into clinical use in the near future. With its high sensitivity, specificity, and multiplexed measurement capacity, it provides great opportunities to improve melanoma treatment, which will ultimately lead to enhanced patient survival rates.

Facile synthesis of a triazine-based porous organic polymer containing thiophene units for effective loading and releasing of temozolomide

Suzuki cross-coupling reaction was employed to easily obtain a triazine-based porous organic polymer (2,4,6-tris(5-bromothiophene-2-yl)-1,3,5-triazine [TBrTh]–1,3,5-benzene-triyltriboronic acid pinacol ester [BTBPE]–covalent triazine framework [CTF]) containing thiophene units. The chemical structure of TBrTh–BTBPE–CTF was revealed by solid-state 13C NMR, Fourier-transform infrared, and X-ray photoelectron spectroscopy. TBrTh–BTBPE–CTF with an amorphous structure exhibited excellent thermal stability and intrinsic porosity (373 m2·g−1 of Brunauer–Emmett–Teller surface area). Consequently, temozolomide (TMZ) was used as an oral alkylating agent in melanoma treatment to explore the drug loading and releasing behavior of TBrTh–BTBPE–CTF as a result of the low cytotoxicity of thiophene-based polymers. The successful loading of TMZ within the polymeric structure was suggested by thermogravimetric analysis and N2 sorption isotherms. The release experiments were performed in phosphate-buffered saline at pH values of 5.5 and 7.4, exhibiting good controlled-release properties. These results suggest that the current porous organic polymer is expected to be a drug carrier for the delivery and release of TMZ.

Gold nanoblackbodies mediated plasmonic photothermal cancer therapy for melanoma

Aim: Gold nanoblackbodies (AuNBs)-mediated plasmonic photothermal cancer therapy was investigated through melanoma-bearing mice. Materials & methods: Polydopamine-coated Au nanoclusters were synthesized, termed AuNBs and PEGylated AuNBs (AuNBs-PEG). The photothermal response of AuNBs-PEG was evaluated upon low-intensity broadband near-infrared irradiation (785/62 nm; 0.9 Wcm^-2), and cytotoxicity was assessed on B16-F10 cells. Further, the therapeutic potential of intravenously administered AuNBs-PEG was evaluated on B16-F10 melanoma in C57BL/6 mice. Results: AuNBs-PEG showed an excellent photothermal response (photothermal conversion efficiency of 60.3%), robust photothermal stability and no cytotoxicity. For AuNB-mediated plasmonic photothermal therapy, an average temperature of 63°C was attained within 5 min of irradiation, and tumors were eradicated. Conclusion: AuNBs-PEG are promising photothermal agents for treating melanoma through low-intensity broadband near-infrared irradiation.

Advances in Photodynamic Therapy Based on Nanotechnology and Its Application in Skin Cancer

Comprehensive cancer treatments have been widely studied. Traditional treatment methods (e.g., radiotherapy, chemotherapy), despite ablating tumors, inevitably damage normal cells and cause serious complications. Photodynamic therapy (PDT), with its low rate of trauma, accurate targeting, synergism, repeatability, has displayed great advantages in the treatment of tumors. In recent years, nanotech-based PDT has provided a new modality for cancer treatment. Direct modification of PSs by nanotechnology or the delivery of PSs by nanocarriers can improve their targeting, specificity, and PDT efficacy for tumors. In this review, we strive to provide the reader with a comprehensive overview, on various aspects of the types, characteristics, and research progress of photosensitizers and nanomaterials used in PDT. And the application progress and relative limitations of nanotech-PDT in non-melanoma skin cancer and melanoma are also summarized.

Skin cancer biology and barriers to treatment: Recent applications of polymeric micro/nanostructures

Background

Skin cancer has been the leading type of cancer worldwide. Melanoma and non-melanoma skin cancers are now the most common types of skin cancer that have been reached to epidemic proportion. Based on the rapid prevalence of skin cancers, and lack of efficient drug delivery systems, it is essential to surge the possible ways to prevent or cure the disease.

Aim of review

Although surgical modalities and therapies have been made great progress in recent years, however, there is still an urgent need to alleviate its increased burden. Hence, understanding the precise pathophysiological signaling mechanisms and all other factors of such skin insults will be beneficial for the development of more efficient therapies.

Key scientific concepts of review

In this review, we explained new understandings about onset and development of skin cancer and described its management via polymeric micro/nano carriers-based therapies, highlighting the current key bottlenecks and future prospective in this field. In therapeutic drug/gene delivery approaches, polymeric carriers-based system is the most promising strategy. This review discusses that how polymers have successfully been exploited for development of micro/nanosized systems for efficient delivery of anticancer genes and drugs overcoming all the barriers and limitations associated with available conventional therapies. In addition to drug/gene delivery, intelligent polymeric nanocarriers platforms have also been established for combination anticancer therapies including photodynamic and photothermal, and for theranostic applications. This portfolio of latest approaches could promote the blooming growth of research and their clinical availability.

Nanoparticle-Based Drug Delivery Systems for Photodynamic Therapy of Metastatic Melanoma: A Review

Metastatic melanoma (MM) is a skin malignancy arising from melanocytes, the incidence of which has been rising in recent years. It poses therapeutic challenges due to its resistance to chemotherapeutic drugs and radiation therapy. Photodynamic therapy (PDT) is an alternative non-invasive modality that requires a photosensitizer (PS), specific wavelength of light, and molecular oxygen. Several studies using conventional PSs have highlighted the need for improved PSs for PDT applications to achieve desired therapeutic outcomes. The incorporation of nanoparticles (NPs) and targeting moieties in PDT have appeared as a promising strategy to circumvent various drawbacks associated with non-specific toxicity, poor water solubility, and low bioavailability of the PSs at targeted tissues. Currently, most studies investigating new developments rely on two-dimensional (2-D) monocultures, which fail to accurately mimic tissue complexity. Therefore, three-dimensional (3-D) cell cultures are ideal models to resemble tumor tissue in terms of architectural and functional properties. This review examines various PS drugs, as well as passive and active targeted PS nanoparticle-mediated platforms for PDT treatment of MM on 2-D and 3-D models. The overall findings of this review concluded that very few PDT studies have been conducted within 3-D models using active PS nanoparticle-mediated platforms, and so require further investigation.

Dual Photothermal/Chemotherapy of Melanoma Cells with Albumin Nanoparticles Carrying Indocyanine Green and Doxorubicin Leads to Immunogenic Cell Death

Recent focus on cancer immunotherapies has led to significant interest in the development of therapeutic strategies that can lead to immunogenic cell death (ICD), which can cause activation of an immune response against tumor cells and improve immunotherapy outcomes by enhancing the immunogenicity of the tumor microenvironment. In this work, a nanomedicine-mediated combination therapy is used to deliver the ICD inducers doxorubicin (Dox), a chemotherapeutic agent, and indocyanine green (ICG), a photothermal agent. These agents are loaded into nanoparticles (NPs) of bovine serum albumin (BSA) that are prepared through a desolvation process. The formulation of BSA NPs is optimized to achieve NPs of 102.6  nm in size and loadings of 8.55 % and 5.69 % (w/w) for ICG and Dox, respectively. The controlled release of these agents from the BSA NPs is confirmed. Upon laser irradiation for 2.5 min, NPs at a dose of 62.5 μg mL^-1 are able to increase the temperature of the cells by 7 °C and thereby inhibit the growth of B16F10 melanoma cells in vitro. Surface presentation of heat shock proteins and calreticulin from the cells after treatment confirmed the ability of the Dox/ICG loaded BSA NPs to induce ICD in the melanoma cells.

Self-assembled polymeric nanocarrier-mediated co-delivery of metformin and doxorubicin for melanoma therapy

Malignant melanoma is a life-threatening form of skin cancer with a low response rate to single-agent chemotherapy. Although combined therapies of metformin (MET) and doxorubicin (DOX) are effective in treating a variety of cancers, including breast cancer, their different physicochemical properties and administration routines reduce the effective co-accumulation of both drugs in tumors. Nanoparticles (NPs) have been demonstrated to potentially improve drug delivery efficiency in cancer therapy of, for example, liver and lung cancers. Hence, in this study, we prepared pH-sensitive, biocompatible, tumor-targeting NPs based on the conjugation of biomaterials, including sodium alginate, cholesterol, and folic acid (FCA). As expected, since cholesterol and folic acid are two essentials, but insufficient, substrates for melanoma growth, we observed that the FCA NPs specifically and highly effectively accumulated in xenograft melanoma tumors. Taking advantage of the FCA NP system, we successfully co-delivered a combination of MET and DOX into melanoma tumors to trigger pyroptosis, apoptosis, and necroptosis (PANoptosis) of the melanoma cells, thus blocking melanoma progression. Combined, the establishment of such an FCA NP system provides a promising vector for effective drug delivery into melanoma and increases the possibility and efficiency of drug combinations for cancer treatment.

Therapeutic potential of a copper complex loaded in pH-sensitive long circulating liposomes for colon cancer management

Colorectal carcinoma is a complex malignancy and current therapies are hampered by systemic toxicity and tumor resistance to treatment. In the field of cancer therapy, copper (Cu) compounds hold great promise, with some reaching clinical trials. However, the anticancer potential of Cu complexes has not yet been fully disclosed due to speciation in biological systems, leading to inactivation and/or potential side effects. This is the case of the widely studied Cu(II) complexes featuring phenanthroline ligands, with potent antiproliferative effects in vitro, but often failing in vivo. Aiming to overcome these limitations and maximize its anticancer effects in vivo, the Cu(II) complex (Cu(1,10-phenanthroline)Cl₂) (Cuphen), displaying IC₅₀ values <6 μM against different tumor cell lines, was loaded in long circulating liposomes with pH-sensitive properties (F1, DMPC:CHEMS:DSPE-PEG; F2, DOPE:CHEMS:DMPC:DSPE-PEG). This enabled a pH-dependent Cuphen release, with F1 and F2 releasing 36/78% and 47/94% of Cuphen at pH 6/4.5, respectively. The so formed nanoformulations preserved Cuphen effects towards cancer cell lines, with F2 presenting IC₅₀ of 2.7 μM and 4.9 μM towards colon cancer CT-26 and HCT-116 cells, respectively. Additional in vitro studies confirmed that Cuphen antiproliferative activity towards colon cancer cells does not rely on cell cycle effect. Furthermore, in these cells, Cuphen reduced glycerol permeation and impaired cell migration. At 24 h incubation, wound closure was reduced by Cuphen, with migration values of 29% vs 54% (control) and 45% (1,10-phenanthroline) in CT-26 cells, and 33% vs ~44% (control and 1,10-phenanthroline) in HCT-116 cells. These effects were probably due to inhibition of aquaglyceroporins, membrane water and glycerol channels that are often abnormally expressed in tumors. In a syngeneic murine colon cancer model, F2 significantly reduced tumor progression, compared to the control group and to mice treated with free Cuphen or with the ligand, 1,10-phenanthroline, without eliciting toxic side effects. F2 led to a tumor volume reduction of ca. 50%. This was confirmed by RTV analysis, where F2 reached a value of 1.3 vs 4.4 (Control), 5.8 (Phen) and 3.8 (free Cuphen). These results clearly demonstrated the important role of the Cu(II) for the observed biological activity that was maximized following the association to a lipid-based nanosystem. Overall, this study represents a step forward in the development of pH-sensitive nanotherapeutic strategies of metallodrugs for colon cancer management.

Non-invasive transdermal delivery of chemotherapeutic molecules in vivo using superparamagnetic iron oxide nanoparticles

Background

The skin is both a target and a potential conduit for the delivery of drugs, but its cornified cell layer resists penetration by most molecules. This study investigated the potential of superparamagnetic iron oxide nanoparticles to facilitate the transdermal delivery of anticancer agents.

Results

Chemotherapeutic cancer drugs were applied with or without nanoparticles to the skin of hairless mice, and their ability to penetrate the skin was assessed using fluorescence microscopy and tumor growth. Nanoparticles enhanced the penetration of the skin by doxorubicin and 5-fluorouracil as determined by fluorescence microscopy and growth retardation of experimental melanoma in immunocompetent, syngeneic mice. This drug enhancement did not require conjugation or encapsulation of the drugs by the nanoparticles—simple co-administration sufficed. Nanoparticles applied topically to melanomas increased the cytotoxicity and immune cell infiltration induced by co-administered 5-fluorouracil, and also reduced vascularization of the tumors independently of 5-fluorouracil.

Conclusion

Correctly formulated superparamagnetic iron oxide nanoparticles can facilitate the chemotherapeutic effectiveness of cytotoxic drugs on skin tumors by both increasing their transdermal penetration and ameliorating host–tumor interactions. This enhancement of skin penetration occurs without the need for conjugation or encapsulation of the co-administered drugs, and so will likely be applicable to other drugs, also.

Therapeutic strategies and potential implications of silver nanoparticles in the management of skin cancer

Skin cancer (SC) is the most common carcinoma affecting 3 million people annually in the United States and millions of people worldwide. It is classified as melanoma SC (MSC) and non-melanoma SC (NMSC). NMSC represents approximately 80% of SC and includes squamous cell carcinoma and basal cell carcinoma. MSC, however, has a higher mortality rate than SC because of its ability to metastasize. SC is a major health problem in the United States with significant morbidity and mortality in the Caucasian population. Treatment options for SC include cryotherapy, excisional surgery, Mohs surgery, curettage and electrodessication, radiation therapy, photodynamic therapy, immunotherapy, and chemotherapy. Treatment is chosen based on the type of SC and the potential for side effects. Novel targeted therapies are being used with increased frequency for large tumors and for metastatic disease. A scoping literature search on PubMed, Google Scholar, and Cancer Registry websites revealed that traditional chemotherapeutic drugs have little effect against SC after the cancer has metastasized. Following an overview of SC biology, epidemiology, and treatment options, this review focuses on the mechanisms of advanced technologies that use silver nanoparticles in SC treatment regimens.

Topical Administration of Terpenes Encapsulated in Nanostructured Lipid-Based Systems

Terpenes are a group of phytocompounds that have been used in medicine for decades owing to their significant role in human health. So far, they have been examined for therapeutic purposes as antibacterial, anti-inflammatory, antitumoral agents, and the clinical potential of this class of compounds has been increasing continuously as a source of pharmacologically interesting agents also in relation to topical administration. Major difficulties in achieving sustained delivery of terpenes to the skin are connected with their low solubility and stability, as well as poor cell penetration. In order to overcome these disadvantages, new delivery technologies based on nanostructures are proposed to improve bioavailability and allow controlled release. This review highlights the potential properties of terpenes loaded in several types of lipid-based nanocarriers (liposomes, solid lipid nanoparticles, and nanostructured lipid carriers) used to overcome free terpenes' form limitations and potentiate their therapeutic properties for topical administration.

Iron Oxide/Salicylic Acid Nanoparticles as Potential Therapy for B16F10 Melanoma Transplanted on the Chick Chorioallantoic Membrane

Unfavorable prognoses and low survival rates are specific features of metastatic melanoma that justify the concern for the development of new therapeutic strategies. Lately, nanotechnology has become an attractive field of study due to recent advances in nanomedicine. Using a chick chorioallantoic membrane (CAM) implanted with xenografts harvested from C57BL/6 mice with B16F10 melanoma cells, we studied the effects of iron oxide nanoparticles functionalized with salicylic acid (SaMNPs) as a form of therapy on the local development of xenotransplants and CAM vessels. The SaMNPs induced an anti-angiogenic effect on the CAM vessels, which accumulated preferentially in the melanoma cells and induced apoptosis and extensive xenograft necrosis. As a result, this slowed the increase in the xenograft volume and reduced the melanoma cells’ ability to metastasize locally and distally. Further, we demonstrate the use of the chick CAM model as a tool for testing the action of newly synthesized nanocomposites on melanoma xenotransplants. The SaMNPs had a therapeutic effect on B16F10 melanoma due to the synergistic action of the two components of its structure: the coating of the salicylic acid with antiangiogenic and chemotherapeutic action and the core of iron oxides with cytotoxic action.

Benign prostatic hyperplasia treatment using plasmonic nanoparticles irradiated by laser in a rat model

OBJECTIVE

In the current study we have stimulated the efficacy of plasmonic nanoparticles (NPs) by laser hyperthermia to achieve a less invasive method for tumor photothermal therapy of benign prostatic hyperplasia (BPH).

METHODS

The levels of apoptosis on induced BPH in rats were assessed after treatment and revealed and recorded by various assayed. Moreover, the expression of caspases was considered to demonstrate the apoptotic pathways due to laser induced plasmonic NPs.

RESULTS

In the Laser + NPs group prostate size of induced BPH decreased. Laser + NPs also decreased prostate specific antigen in comparison with the BPH groups. Furthermore, Laser + NPs attenuated BPH histopathologic indices in the rats. Laser + NPs induced apoptosis in prostatic epithelial cells via caspase-1 pathway.

CONCLUSIONS

Altogether, the approach and findings from this study can be applied to introduce the laser irritated NPs method as a novel and less invasive therapy for patients suffering from BPH.

Emergent Nanotechnological Strategies for Systemic Chemotherapy against Melanoma

Melanoma is an aggressive form of skin cancer, being one of the deadliest cancers in the world. The current treatment options involve surgery, radiotherapy, targeted therapy, immunotherapy and the use of chemotherapeutic agents. Although the last approach is the most used, the high toxicity and the lack of efficacy in advanced stages of the disease have demanded the search for novel bioactive molecules and/or efficient drug delivery systems. The current review aims to discuss the most recent advances on the elucidation of potential targets for melanoma treatment, such as aquaporin-3 and tyrosinase. In addition, the role of nanotechnology as a valuable strategy to effectively deliver selective drugs is emphasized, either incorporating/encapsulating synthetic molecules or natural-derived compounds in lipid-based nanosystems such as liposomes. Nanoformulated compounds have been explored for their improved anticancer activity against melanoma and promising results have been obtained. Indeed, they displayed improved physicochemical properties and higher accumulation in tumoral tissues, which potentiated the efficacy of the compounds in pre-clinical experiments. Overall, these experiments opened new doors for the discovery and development of more effective drug formulations for melanoma treatment.

Simultaneous Photodiagnosis and Photodynamic Treatment of Metastatic Melanoma

Metastatic melanoma (MM) has a poor prognosis and is attributed to late diagnoses only when metastases has already occurred. Thus, early diagnosis is crucial to improve its overall treatment efficacy. The standard diagnostic tools for MM are incisional biopsies and/or fine needle aspiration biopsies, while standard treatments involve surgery, chemotherapy, or irradiation therapy. The combination of photodynamic diagnosis (PDD) and therapy (PDT) utilizes a photosensitizer (PS) that, when excited by light of a low wavelength, can be used for fluorescent non-destructive diagnosis. However, when the same PS is activated at a higher wavelength of light, it can be cytotoxic and induce tumor destruction. This paper focuses on PS drugs that have been used for PDD as well as PDT treatment of MM. Furthermore, it emphasizes the need for continued investigation into enhanced PS delivery via active biomarkers and passive nanoparticle systems. This should improve PS drug absorption in MM cells and increase effectiveness of combinative photodynamic methods for the enhanced diagnosis and treatment of MM can become a reality.

Copper complex nanoformulations featuring highly promising therapeutic potential in murine melanoma models

Aim: Preclinical evaluation of a cytotoxic copper (II) complex formulated in long circulating nanoliposomes for melanoma treatment. Materials & methods: Liposomal nanoformulations of the copper complex were characterized in terms of thermodynamic behavior (differential scanning calorimeter), pH-sensitivity (spectrophotometry) and antiproliferative effects against murine melanoma B16F10 cells in vitro. Preclinical studies were performed in a C57BL/6 syngeneic melanoma model. Results: Nanoformulations were thermodynamically stable, and CHEMS-containing nanoliposomes were pH-sensitive and preserved the antiproliferative properties of the copper compound. These nanoformulations significantly impaired tumor progression in vivo, devoid of toxic side effects, compared with control mice or mice treated with the free metallodrug. Conclusion: Copper complex-containing nanoliposomes demonstrate high anticancer efficacy and safety, constituting a step forward to the development of more effective therapeutic strategies against melanoma.

PD-L1 knockdown via hybrid micelle promotes paclitaxel induced Cancer-Immunity Cycle for melanoma treatment

The Cancer-Immunity Cycle is a series of anticancer immune responses initiated and allowed to proceed and expand iteratively. Paclitaxel (PTX) is a classic chemotherapeutic agent, which could induce immunogenic cell death (ICD) to trigger the Cancer-Immunity Cycle. However, the Cycle is severely impaired by tumor cell immunosuppression of host T cell antitumor activity through the programmed cell death receptor 1 (PD-1) and programmed cell death ligand 1 (PD-L1) (PD-1/PD-L1) immune checkpoint pathway. Here, we demonstrated that PTX mediated the Cancer-Immunity Cycle could be enhanced by PD-L1 knockdown (KD) and followed mTOR pathway inhibition in tumor cells. PD-L1 siRNA (siP) and the hydrophobic chemotherapy drug PTX were co-delivered with a rationally designed hybrid micelle (HM). We showed clear evidence that the HM-siP/PTX is capable of delivering siP and PTX simultaneously to the B16F10 cells both in vitro and in vivo. We demonstrated that HM-PTX/siP reduced the expression of PD-L1 and p-S6K (a marker of mTOR pathway activation) both in vitro and in melanoma-bearing mice and attenuated synergistically tumor growth by chemical toxicity, promoting cytotoxic T-cell immunity and suppressing the mTOR pathway.

New insights into molecular mechanisms of rosiglitazone in monotherapy or combination therapy against cancers

Rosiglitazone (ROSI), a member of thiazolidinediones (TZDs) which act as high-affinity agonists of the nuclear receptor peroxisome-proliferator-activated receptor-γ (PPARγ), is clinically used as an antidiabetic drug which could attenuate the insulin resistance associated with obesity, hypertension, and impaired glucose tolerance in humans. However, recent studies reported that ROSI had significant anticancer effects on various human malignant tumor cells. Mounting evidence indicated that ROSI could exert anticancer effects through PPARγ-dependent or PPARγ-independent ways. In this review, we summarized the PPARγ-dependent antitumor activities of ROSI, which included apoptosis induction, inhibition of cell proliferation and cancer metastasis, reversion of multidrug resistance, reduction of immune suppression, autophagy induction, and antiangiogenesis; and the PPARγ-independent antitumor activities of ROSI, which included inhibition of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway, inhibition of prostaglandin E2 (PGE₂), increasing MAPK phosphatase 1 (MKP-1) expression and regulation of other apoptosis-related cell factors. In addition, we discussed the anti-cancer application of ROSI by monotherapy or combination therapy with present chemotherapeutic drugs in vitro and in vivo. Moreover, we reviewed the phase I cancer clinical trials related to ROSI combined with chemotherapeutics and phase II trials about the anti-cancer effects of ROSI monotherapy and the radiotherapy sensitivity of ROSI.

pH-responsive polymeric micelles self-assembled from amphiphilic copolymer modified with lipid used as doxorubicin delivery carriers

In the present study, a novel pH-responsive amphiphilic copolymer, 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-[methoxy(polyethylene glycol)] conjugated poly(β-amino esters) (DSPE-b-PEG-b-PAE-b-PEG-b-DSPE), was designed and successfully synthesized via Michael-type step polymerization. The chemical structure of the pentablock copolymer was confirmed with proton nuclear magnetic resonance (¹H-NMR) and Fourier transform infrared (FT-IR) spectroscopy. The copolymer was able to self-assemble into core/shell polymeric micelles in aqueous solution at low concentrations, and its critical micelle concentration (CMC) value was 4.5 mg l^-1 determined by fluorescence spectrophotometry. The pK_b value of the copolymer was about 6.5, confirmed by acid-base titration, indicating the pH-sensitivity of the polymeric micelle. The hydrodynamic diameter, distribution and zeta potential of the polymeric micelles at different pH conditions were monitored by dynamic light scattering (DLS). Doxorubicin (DOX) was encapsulated into the core of the micelles with a high drug loading content (15.9%) and entrapment efficacy (60.4%). In vitro experiments demonstrated that the release behaviour of DOX from the DOX-loaded polymeric micelles (DOX-PMs) was pH-triggered. When the pH decreased from 7.4 to 5.0, the drug release rate was markedly accelerated. MTT assay showed that the copolymer had negligible cytotoxicity whereas the DOX-PMs displayed high toxicity for tumour cells such as B16F10, HepG2 and HeLa cell lines. The results demonstrated that these pH-sensitive polymeric micelles could be used as potential anti-cancer drug carriers for cancer chemotherapy with controlled release.

Photodynamic Therapy for Metastatic Melanoma Treatment: A Review

This review article is based on specifically targeted nanoparticles that have been used in the treatment of melanoma. According to the Skin Cancer Foundation, within 2017 an estimated 9730 people will die due to invasive melanoma. Conventional treatments for nonmalignant melanoma include surgery, chemotherapy, and radiation. For the treatment of metastatic melanoma, 3 therapeutic agents have been approved by the Food and Drug Administration: dacarbazine, recombinant interferon α-2b, and high-dose interleukin 2. Photodynamic therapy is an alternative therapy that activates a photosensitizer at a specific wavelength forming reactive oxygen species which in turn induces cell death; it is noninvasive with far less side effects when compared to conventional treatments. Nanoparticles are generally conjugated to photosynthetic drugs, since they are biocompatible, stabile, and durable, as well as have a high loading capacity, which improve either passive or active photosensitizer drug delivery to targeted cells. Therefore, various photosynthetic drugs and nanoparticle drug delivery systems specifically targeted for melanoma were analyzed in this review article in relation to either their passive or their active cellular uptake mechanisms in order to deduce the efficacy of photodynamic therapy treatment for metastatic melanoma which currently remains ongoing. The overall findings from this review concluded that no current photodynamic therapy studies have been performed in relation to active nanoparticle platform photosensitizer drug carrier systems for the treatment of metastatic melanoma, and so this type of research requires further investigation into developing a more efficient active nano-photosensitizer carrier smart drug that can be conjugated to specific cell surface receptors and combinative monoclonal antibodies so that a further enhanced and more efficient form of targeted photodynamic therapy for the treatment of metastatic melanoma can be established.