Current and future trials of targeted therapies in cutaneous melanoma

The inhibitory role of microRNA-141-3p in human cutaneous melanoma growth and metastasis through the fibroblast growth factor 13-mediated mitogen-activated protein kinase axis

Human cutaneous melanoma (CM) is a highly invasive malignancy arising from melanocytes, and accompanied by ever-increasing incidence and mortality rates worldwide. Interestingly, microRNAs (miRNAs) possess the ability to regulate CM cell biological functions, resulting in the aggressive progression of CM. Nevertheless, a comprehensive understanding of the underlying mechanism remains elusive. Accordingly, the current study sought to elicit the functional role of miR-141-3p in human CM cells in association with fibroblast growth factor 13 (FGF13) and the MAPK pathway. First, miR-141-3p expression patterns were detected in human CM tissues and cell lines, in addition to the validation of the targeting relationship between miR-141-3p and FGF13. Subsequently, loss- and gain-of-function studies of miR-141-3p were performed to elucidate the functional role of miR-141-3p in the malignant features of CM cells. Intriguingly, our findings revealed that FGF13 was highly expressed, whereas miR-141-3p was poorly expressed in the CM tissues and cells. Further analysis highlighted FGF13 as a target gene of miR-141-3p. Meanwhile, overexpression of miR-141-3p inhibited the proliferative, invasive, and migratory abilities of CM cells, while enhancing their apoptosis accompanied by downregulation of FGF13 and the MAPK pathway-related genes. Collectively, our findings highlighted the inhibitory effects of miR-141-3p on CM cell malignant properties via disruption of the FGF13-dependent MAPK pathway, suggesting a potential target for treating human CM.

Two-team-approached free flap reconstruction for plantar malignant melanoma: An observational (STROBE-compliant) trial

Reconstructive treatments of heel defects usually involve regional flap techniques such as medial plantar flap procedures due to the limited availability of adjacent soft tissues. Although free flaps have advantages in terms of function and aesthetics, they remain challenging due to the longer operation time required than for regional flaps. Thus, we introduce an appropriate 2-team surgical protocol to reconstruct plantar defects after wide excision of malignant melanoma using free flap coverage. From 2015 to 2020, a retrospective study was performed including 21 patients who underwent free flap surgeries to reconstruct defects due to plantar malignant melanoma. Lymphoscintigraphy was performed to localize sentinel lymph nodes, and the procedure was carried out by 2 teams working together, a tumor-ablative team and a reconstructive team. The present study is adhered to the STROBE guidelines for cohort studies. The average operation time was 241.4 minutes and was not significantly different even in cases with inguinal dissection (P value: 0.641). All flaps survived after 2 cases of venous insufficiency and 1 case of hematoma were resolved by immediate revision surgery. The 2-team approach to surgically reconstruct heel defects after wide excision of malignant melanoma using free flap coverage offers favorable results and lower morbidity than regional flap approaches.

CB-RAF600E-1 exerts efficacy in vemurafenib-resistant and non-resistant-melanoma cells via dual inhibition of RAS/RAF/MEK/ERK and PI3K/Akt signaling pathways

Background and Aim

Predicting novel dual inhibitors to combat adverse effects such as the development of resistance to vemurafenib in melanoma treatment due to the reactivation of MAPK and PI3K/AKT signaling pathways is studied to help in reversal of cancer symptoms.

Reversal of cancer symptoms in melanoma associated with vemurafenib resistance is driven by reactivation of MAPK and PI3K/Akt signaling pathways. Novel dual inhibitors targeting these proteins would be beneficial to combat resistance.

Methods

High-throughput virtual screening of the ChemBridge library against B-RAFV600E and Akt was performed using an automated protocol with the AutoDock VINA program. Luminescence and time-resolved fluorescence kits were used to measure enzyme activities. The MTT assay was used to determine proliferation in normal and vemurafenib-resistant A375 cells. Flow cytometry was used to examine apoptosis, cell cycle, and phosphorylation of ERK/Akt signaling pathway.

Results

High-throughput screening from the ChemBridge library identified 15 compounds with high binding energy towards B-RAFV600E; among these, CB-RAF600E-1 had the highest ΔG_binding score −11.9 kcal/mol. The compound also had a high affinity towards Akt, with a ΔG_binding score of −11.5 kcal/mol. CB-RAF600E-1 dose-dependently inhibited both B-RAFV600E and Akt with IC₅₀ values of 635 nM and 154.3 nM, respectively. The compound effectively controlled the proliferations of normal and vemurafenib-resistant A375 cells, with GI₅₀ values of 222.3 nM and 230.5 nM, respectively. A dose-dependent increase in the sub G₀/G₁ phase of the cell cycle and total apoptosis was observed following compound treatment in both normal and vemurafenib-resistant melanoma cells. Treatment with CB-RAF600E-1 decreased the pERK/pAkt dual-positive populations in normal and vemurafenib-resistant A375 cells.

Conclusion

CB-RAF600E-1, identified as a novel dual inhibitor effective against normal and vemurafenib-resistant melanoma cells, requires further attention for development as an effective chemotherapeutic agent for melanoma management.

Treatment beyond progression and locoregional approaches in selected patients with BRAF-mutated metastatic melanoma

The clinical management of BRAF-mutated metastatic melanoma had an important turning point after the introduction of the targeted therapy. Despite the efficacy and good tolerability of this treatment, the development of resistance mechanisms causes disease progression. The aim of this review is to investigate the role of treatment beyond progression and locoregional approaches in BRAF-mutated metastatic melanoma and provide oncologists dealing with this malignancy a useful road map on when and why to choose this strategy.

The article is structured in the form of a narrative review reporting the most significant studies on the subject. Most of the available articles are represented by retrospective studies and case reports, leading to limitations in the final interpretations. Nevertheless, a correct analysis of the selected studies allows the drawing of some conclusions. In well-selected cases, treatment beyond progression could play an important role in the treatment sequence of patients with BRAF-mutated advanced melanoma and would seem to produce good disease control rates and positive survival outcomes. A careful evaluation of the radiological examinations and laboratory tests, based on the clinical conditions, allows the identification of which patients can benefit from this strategy. Such patients are those who, at the time of progression, have favourable features such as a lower performance status according to Eastern Cooperative Oncology Group (ECOG-PS), normal lactate dehydrogenase levels and lower disease burden. The clinical benefit is also consolidated by the addition of locoregional approaches. Locoregional approaches can include electrochemotherapy, radiotherapy or surgery, and their use provides local disease control and a better quality of life for patients.

Green Propolis Compounds (Baccarin and p-Coumaric Acid) Show Beneficial Effects in Mice for Melanoma Induced by B16f10

Background: Cutaneous melanoma is the most aggressive form of skin cancer, with the worst prognosis, and it affects a younger population than most cancers. The high metastatic index, in more advanced stages, and the high aggressiveness decrease the effectiveness of currently used therapies, such as surgical removal, radiotherapy, cryotherapy, and chemotherapy, used alone or in combination. Based on these disadvantages, research focused on alternative medicine offers great potential for therapeutic innovation. Medicinal plants represent a remarkable source of compounds for the treatment of various diseases. Methods: In this study, we investigated the tumoral behavior of melanoma under treatment with the compounds baccharin and p-coumaric acid, extracted from green propolis, in mice inoculated with B16F10 cells for 26 days. Results: A significant modulation in the number of inflammatory cells recruited to the tumor region and blood in the groups treated with the compounds was observed. In addition, a significant reduction in the amount of blood vessels and mitosis in the neoplastic area was noticed. Conclusions: Through our research, we confirmed that baccharin and coumaric acid, isolated substances from Brazilian green propolis, have a promising anticarcinogenic potential to be explored for the development of new antitumor agents, adhering to the trend of drugs with greater tolerance and biological effectiveness.

Use of Nanoparticles in Delivery of Nucleic Acids for Melanoma Treatment

Melanoma accounts for 4% of all skin cancer malignancies, with only 14% of diagnosed patients surviving for more than 5 years after diagnosis. Until now, there is no clear understanding of the detailed molecular contributors of melanoma pathogenesis. Accordingly, more research is needed to understand melanoma development and prognosis.All the treatment approaches that are currently applied have several significant limitations that prevent effective use in melanoma. One major limitation in the treatment of cancer is the acquisition of multidrug resistance (MDR). The MDR results in significant treatment failure and poor clinical outcomes in several cancers, including skin cancer. Treatment of melanoma is especially retarded by MDR. Despite the current advances in targeted and immune-mediated therapy, treatment arms of melanoma are severely limited and stand as a significant clinical challenge. Further, the poor pharmacokinetic profile of currently used chemotherapeutic agents is another reason for treatment failure. Therefore, more research is needed to develop novel drugs and carrier tools for more effective and targeted treatment.Nucleic acid therapy is based on nucleic acids or chemical compounds that are closely related, such as antisense oligonucleotides, aptamers, and small-interfering RNAs that are usually used in situations when a specific gene implicated in a disorder is deemed a therapeutically beneficial target for inhibition. However, the proper application for nucleic acid therapies is hampered by the development of an effective delivery system that can maintain their stability in the systemic circulation and enhance their uptake by the target cells. In this chapter, the prognosis of the different types of melanoma along with the currently used medications is highlighted, and the different types of nucleic acids along with the currently available nanoparticle systems for delivering these nucleic acids into melanoma cells are discussed. We also discuss recently conducted research on the use of different types of nanoparticles for nucleic acid delivery into melanoma cells and highlight the most significant outcomes.

A pH-Sensitive Prodrug Nanocarrier Based on Diosgenin for Doxorubicin Delivery to Efficiently Inhibit Tumor Metastasis

BACKGROUND

The metastasis, one of the biggest barriers in cancer therapy, is the leading cause of tumor deterioration and recurrence. The anti.-metastasis has been considered as a feasible strategy for clinical cancer management. It is well known that diosgenin could inhibit tumor metastasis and doxorubicin (DOX) could induce tumor apoptosis. However, their efficient delivery remains challenging.

PURPOSE

To address these issues, a novel pH-sensitive polymer-prodrug based on diosgenin nanoparticles (NPs) platform was developed to enhance the efficiency of DOX delivery (DOX/NPs) for synergistic therapy of cutaneous melanoma, the most lethal form of skin cancer with high malignancy, early metastasis and high mortality.

METHODS AND RESULTS

The inhibitory effect of DOX/NPs on tumor proliferation and migration was superior to that of NPs or free DOX. What is more, DOX/NPs could combine mitochondria-associated metastasis and apoptosis with unique internalization pathway of carrier to fight tumors. In addition, biodistribution experiments proved that DOX/NPs could efficiently accumulate in tumor sites through enhancing permeation and retention (EPR) effect compared with free DOX. Importantly, the data from in vivo experiment revealed that DOX/NPs without heart toxicity significantly inhibited tumor metastasis by exerting synergistic therapeutic effect, and reduced tumor volume and weight by inducing apoptosis.

CONCLUSION

The nanocarrier DOX/NPs with satisfying pharmaceutical characteristics based on the establishment of two different functional agents is a promising strategy for synergistically enhancing effects of cancer therapy.

Hydrogen-Peroxide-Responsive Protein Biomimetic Nanoparticles for Photothermal-Photodynamic Combination Therapy of Melanoma

BACKGROUND AND OBJECTIVES

Recently, there has been a rapid increase in the incidences of melanoma, which represents a serious threat to human health. Generally, tumor-microenvironment-responsive nanoparticle-based photothermal-photodynamic combination therapy (PTT-PDT) is characterized by intratumoral response and tumor targeting. In this study, we designed and synthesized hydrogen-peroxide-responsive protein biomimetic nanoparticles (MnO₂ -ICG@BSA) for the treatment of melanoma.

STUDY DESIGN/MATERIALS AND METHODS

Briefly, MnO₂ -ICG@BSA was prepared using a mild protein synthesis method by loading indocyanine green (ICG) into a bovine serum albumin-manganese dioxide complex (MnO₂ @BSA); next, its characteristics were determined. In addition, in vitro biocompatibility and antitumor efficacy were assessed using the classic cell counting kit-8 assay. Moreover, in vivo high-frequency ultrasound and thermal imaging were used to evaluate the oxygen-production capacity and photothermal conversion effect of MnO₂ -ICG@BSA at the tumor site, and Singlet Oxygen Sensor Green (SOSG) was used to measure singlet oxygen levels in the tumor. The antitumor efficacy was assessed based on relative tumor size, bodyweight, survival curves, and hematoxylin and eosin staining.

RESULTS

The results showed that MnO₂ -ICG@BSA has a high photothermal conversion efficiency, a strong singlet oxygen-generation ability, and high photothermal stability. In addition, in vitro PTT-PDT experiments showed that MnO₂ -ICG@BSA has a significant inhibitory effect on the proliferation of B16F10 melanoma cells. Meanwhile, in vivo experiments showed that MnO₂ -ICG@BSA has a significant inhibitory effect on melanoma in mice. Preliminary toxicity studies indicated that MnO₂ -ICG@BSA exhibits low toxicity.

CONCLUSION

From the results, we can conclude that MnO₂ -ICG@BSA could be used in PTT-PDT to treat melanoma, making it a good candidate material for PTT-PDT. Lasers Surg. Med. © 2020 Wiley Periodicals LLC.

Cutaneous Malignant Melanoma and Targeted Therapy Based on the Biomarkers

Malignant melanoma is the most aggressive form of cutaneous malignancy. It accounts for more than 75% of cancer-related deaths among cutaneous malignancies. It accounts for <5% of cutaneous malignancy. Numerous biomarkers are used in malignant melanoma with varying clinical applications, including diagnostic purposes, prognosis, therapeutic purpose, and targeted therapy against melanoma. Systemic chemotherapy in malignant melanoma has little benefit compared to immunotherapy and targeted therapy. The observed overall survival with systemic chemotherapy is much less compared with targeted therapy in advanced or metastatic melanoma. Various targeted therapies are currently used in melanoma treatment including BRAF inhibitors such as vemurafenib and dabrafenib; MEK inhibitors such as trametinib; anti-CTLA-4 antibodies such as ipilimumab; and anti-programmed cell death 1 antibodies such as nivolumab, pembrolizumab, and pidilizumab. This study discusses the role of biomarkers and targeted therapies based on the biomarker.

Luteolin inhibits proliferation and induces apoptosis of human melanoma cells in vivo and in vitro by suppressing MMP-2 and MMP-9 through the PI3K/AKT pathway

Since the incidence rate of malignant melanoma is increasing annually, development of drugs against melanoma cell metastasis has become more urgent. Luteolin, a naturally occurring flavonoid, is abundant in our daily dietary intake and exhibits a wide spectrum of pharmacological properties. However, the potential anti-cancer role of luteolin in melanoma cells has not been fully investigated. In this study, we have explored whether luteolin inhibits the migration and invasion of A375 human melanoma cells and further elucidated the underlying anti-cancer molecular mechanism of luteolin in melanoma cells. A proliferation assay, flow cytometry and an apoptosis assay were applied to detect the effect of luteolin on the growth and apoptosis of A375 cells. Wound healing assay and transwell invasion assay were used to explore the impact of luteolin on the migration and invasion of A375 cells. Real-time quantitative PCR, western blot and immunofluorescence analysis were used to investigate the effects of luteolin on the expressions of MMP-2, MMP-9 and PI3K/AKT1 in A375 cells. A xenograft tumor animal model was used to investigate the anti-cancer effect of luteolin on the growth of the A375 cells in vivo. Our data indicated that luteolin significantly inhibited the proliferation, migration and invasion of A375 cells and induced the apoptosis of A375 cells in a concentration-dependent manner. Moreover, luteolin reduced the expressions of MMP-2 and MMP-9 and increased the expression of TIMP-1 and TIMP-2. Furthermore, luteolin significantly inhibited the tumor growth of A375 cells in a xenograft mouse model. The immunofluorescence and immunoblotting assays indicated that luteolin inhibited the phosphorylation of AKT1 and PI3K. In conclusion, both in vivo and in vitro studies showed that luteolin inhibited the proliferation and induced the apoptosis of A375 human melanoma cells by reducing the expressions of MMP-2 and MMP-9 through the PI3K/AKT pathway. Overall, luteolin can be considered as a promising anti-cancer agent for the treatment of human melanoma.

KCNQ1OT1 promotes melanoma growth and metastasis

Melanoma is the deadliest cutaneous neoplasm. To prevent metastasis, early diagnosis and surgical treatment is vital. Long non-coding RNAs (lncRNAs) may serve as biomarkers and therapeutic targets in tumors. We investigated the molecular mechanisms of lncRNA KCNQ1OT1 in melanoma. Real time PCR demonstrated that KCNQ1OT1 expression is up-regulated in melanoma tissues and cells. KCNQ1OT1 promoted cell proliferation and metastasis in melanoma. By directly bindin to miR-153, KCNQ1OT1 acted as a competing endogenous RNA (ceRNA) to de-repress MET expression. Our results may provide the basis for a novel strategy for early detection and/or treatment of melanoma.

Hinokiflavone induces apoptosis in melanoma cells through the ROS-mitochondrial apoptotic pathway and impairs cell migration and invasion

Melanoma, the highest degree of malignancy, is one of the most common skin tumors. However, there is no effective strategy to treat melanoma in current clinical practice. Therefore, it is urgent to find an efficient drug to overcome melanoma. Here, the in vitro anticancer effects of a natural product named hinokiflavone on three melanoma carcinoma cell lines (human melanoma A375 and CHL-1 cells, murine melanoma B16-F10 cells) and mechanisms of action were explored. The results of MTT assay revealed that hinokiflavone inhibited cell proliferation of these cell lines in a dose- and time-dependent manner. Interestingly, hinokiflavone showed low toxicity to normal liver cells. Flow cytometry assay and EdU incorporation assay indicated that hinokiflavone affected A375 and B16 cells survival by inducing apoptosis and blocking cell cycle progression at S phase in a concentration-dependent manner. Moreover, hinokiflavone enhanced the reactive oxygen species (ROS) and decreased the mitochondrial membrane potential obviously. Furthermore, hinokiflavone effectively impaired A375 cells migration and invasion, and down-regulated the expression of matrix metalloproteinase (MMP) MMP2 and MMP9. The above-mentioned results demonstrated that hinokiflavone could be a novel chemotherapeutic agent in melanoma treatment by inhibiting cell proliferation, inducing apoptosis and cell cycle arresting and blocking cell migration and invasion.

Icariin induces cell differentiation and cell cycle arrest in mouse melanoma B16 cells via Erk1/2-p38-JNK-dependent pathway

Icariin (ICA) is a major component isolated from Epimedium brevicornum. Emerging evidence shows that ICA can inhibit tumor cell proliferation, invasion and migration. However, the anti-cancer effect of ICA on B16 cells has not been fully investigated. Here we found that the proliferation of B16 cells was inhibited by ICA in a concentration- and time-dependent manner, and the colony formation of B16 cells was also inhibited by ICA in a concentration-dependent manner. Further study showed that the melanin content was increased and the tyrosinase (Tyr) activity was enhanced after ICA treatment in B16 cells. Furthermore, compared with the control group, the mRNA levels of Tyr, Trp1 and Trp2 and the protein level of MITF were increased in ICA-treated B16 cells. In addition, the percentage of G0/G1 phase cells was increased and the protein levels of Cyclin A, CDK2 and p21 were decreased in ICA-treated B16 cells. Finally, we found that ICA increased down-regulated the Erk1/2, p-Erk1/2, p38, p-p38, and p-JNK protein levels in B16 cells when compared with the control group. Taken together, these results indicated that ICA could induce B16 cell differentiation and cell cycle arrest at G0/G1 phase through inhibiting Erk1/2-p38-JNK-dependent signaling molecules.

Deoxyarbutin displays antitumour activity against melanoma in vitro and in vivo through a p38-mediated mitochondria associated apoptotic pathway

Deoxyarbutin (DeoxyArbutin, dA), a natural compound widely used in skin lighting, displayed selectively cytotoxicity in vitro. In the study, we found that dA significantly inhibited viability/proliferation of B16F10 melanoma cells, induced tumour cell arrest and apoptosis. Furthermore, dA triggered its pro-apoptosis through damaging the mitochondrial function (membrane potential loss, ATP depletion and ROS overload generation etc.) and activating caspase-9, PARP, caspase-3 and the phosphorylation of p38. Treatment with p38 agonist confirmed the involvement of p38 pathway triggered by dA in B16F10 cells. The in vivo finding also revealed that administration of dA significantly decreased the tumour volume and tumour metastasis in B16F10 xenograft model by inhibiting tumour proliferation and inducing tumour apoptosis. Importantly, the results indicated that dA was specific against tumour cell lines and had no observed systemic toxicity in vivo. Taken together, our study demonstrated that dA could combate tumour in vitro and in vivo by inhibiting the proliferation and metastasis of tumour via a p38-mediated mitochondria associated apoptotic pathway.

Jolkinolide B induces apoptosis and inhibits tumor growth in mouse melanoma B16F10 cells by altering glycolysis

Most cancer cells preferentially rely on glycolysis to produce the energy (adenosine triphosphate, ATP) for growth and proliferation. Emerging evidence demonstrates that the apoptosis in cancer cells could be closely associated with the inhibition of glycolysis. In this study, we have found that jolkinolide B (JB), a bioactive diterpenoid extracted from the root of Euphorbia fischeriana Steud, induced tumor cells apoptosis and decreased the production of ATP and lactic acid in mouse melanoma B16F10 cells. Furthermore, we found that JB downregulated the mRNA expression of glucose transporter genes (Glut1, Glut3 and Glut4) and glycolysis-related kinase genes (Hk2 and Ldha) in B16F10 cells. Moreover, treatment with JB upregulated the mRNA expression of pro-apoptosis genes (Bax), downregulated the mRNA expression of anti-apoptosis genes (Bcl-2, Caspase-3 and Caspase-9), decreased the potential of mitochondrial membrane and increased reactive oxygen species (ROS) levels in B16F10 cells. Finally, intragastric administration of JB suppressed tumor growth and induced tumor apoptosis in mouse xenograft model of murine melanoma B16F10 cells. Taken together, these results suggest that JB could induce apoptosis through the mitochondrial pathway and inhibit tumor growth. The inhibition of glycolysis could play a crucial role in the induction of apoptosis in JB-treated B16F10 cells.

Structurally diverse c-Myc inhibitors share a common mechanism of action involving ATP depletion

The c-Myc (Myc) oncoprotein is deregulated in a large proportion of diverse human cancers. Considerable effort has therefore been directed at identifying pharmacologic inhibitors as potential anti-neoplastic agents. Three such groups of small molecule inhibitors have been described. The first is comprised of so-called “direct” inhibitors, which perturb Myc's ability to form productive DNA-binding heterodimers in association with its partner, Max. The second group is comprised of indirect inhibitors, which largely function by targeting the BET-domain protein BRD4 to prevent the proper formation of transcriptional complexes that assemble in response to Myc-Max DNA binding. Thirdly, synthetic lethal inhibitors cause the selective apoptosis of Myc over-expressing either by promoting mitotic catastrophe or altering Myc protein stability. We report here a common mechanism by which all Myc inhibitors, irrespective of class, lead to eventual cellular demise. This involves the depletion of ATP stores due to mitochondrial dysfunction and the eventual down-regulation of Myc protein. The accompanying metabolic de-regulation causes neutral lipid accumulation, cell cycle arrest, and an attempt to rectify the ATP deficit by up-regulating AMP-activated protein kinase (AMPK). These responses are ultimately futile due to the lack of functional Myc to support the requisite anabolic response. Finally, the effects of Myc depletion on ATP levels, cell cycle arrest, differentiation and AMPK activation can be mimicked by pharmacologic inhibition of the mitochondrial electron transport chain without affecting Myc levels. Thus, all Myc inhibitors promote a global energy collapse that appears to underlie many of their phenotypic consequences.

Therapy for BRAFi-Resistant Melanomas: Is WNT5A the Answer?

In recent years, scientists have advocated the use of targeted therapies in the form of drugs that modulate genes and proteins that are directly associated with cancer progression and metastasis. Malignant melanoma is a dreadful cancer type that has been associated with the rapid dissemination of primary tumors to multiple sites, including bone, brain, liver and lungs. The discovery that approximately 40%–50% of malignant melanomas contain a mutation in BRAF at codon 600 gave scientists a new approach to tackle this disease. However, clinical studies on patients have shown that although BRAFi (BRAF inhibitors) trigger early anti-tumor responses, the majority of patients later develop resistance to the therapy. Recent studies have shown that WNT5A plays a key role in enhancing the resistance of melanoma cells to BRAFi. The focus of the current review will be on melanoma development, signaling pathways important to acquired resistance to BRAFi, and why WNT5A inhibitors are attractive candidates to be included in combinatorial therapies for melanoma.

Nivolumab: a review of its use in patients with malignant melanoma

Nivolumab (Opdivo(®)) is a fully human monoclonal antibody against programmed death receptor-1, a negative regulatory checkpoint molecule with a role in immunosuppression. The drug is administered intravenously and is approved for the treatment of unresectable malignant melanoma in Japan. The potential for intravenous nivolumab to be used in the treatment of advanced malignancies such as melanoma was initially demonstrated in phase I dose-ranging trials. Subsequently, in a noncomparative, open-label, phase II trial, almost one-quarter of Japanese patients with previously treated stage III/IV melanoma (recurrent or unresectable) achieved a partial tumour response with intravenous nivolumab 2 mg/kg every 3 weeks. The clinical benefit of the drug was durable, with patients surviving free from progression for a median of 172 days and median overall survival not yet reached. Nivolumab had an acceptable tolerability profile in this trial, with fewer than 18 % of patients experiencing grade 3 or 4 adverse events related to the drug, the most common of which was increased γ-glutamyl transferase. Thus, nivolumab is an emerging, promising option for the treatment of malignant melanoma.

Cytotoxicity evaluation of carbon-encapsulated iron nanoparticles in melanoma cells and dermal fibroblasts

Carbon-encapsulated iron nanoparticles (CEINs) are emerging as promising biomedical tools due to their unique physicochemical properties. In this study, the cytotoxic effect of CEINs (the mean diameter distribution ranges 46-56 nm) has been explored by MTT, LDH leakage, Calcein-AM/propidium iodide (PI) and Annexin V-FITC/PI assays in human melanoma (HTB-140), mouse melanoma (B16-F10) cells, and human dermal fibroblasts (HDFs). The results demonstrated that CEINs produce mitochondrial and cell membrane cytotoxicities in a dose (0.0001-100 μg/ml)-dependent manner. Moreover, the studies elucidated some differences in cytotoxic effects between CEINs used as raw and purified materials composing of the carbon surface with acidic groups. Experiments showed that HTB-140 cells are more sensitive to prone early apoptotic events due to raw CEINs as compared to B16-F10 or HDF cells, respectively. Taken together, these results suggest that the amount of CEINs administered to cells and the composition of CEINs containing different amounts of iron as well as the carbon surface modification type is critical determinant of cytotoxic responses in both normal and cancer (melanoma) cells.

Use of Nanotechnology to Develop Multi-Drug Inhibitors For Cancer Therapy

Therapeutic agents that inhibit a single target often cannot combat a multifactorial disease such as cancer. Thus, multi-target inhibitors (MTIs) are needed to circumvent complications such as the development of resistance. There are two predominant types of MTIs, (a) single drug inhibitor (SDIs) that affect multiple pathways simultaneously, and (b) combinatorial agents or multi-drug inhibitors (MDIs) that inhibit multiple pathways. Single agent multi-target kinase inhibitors are amongst the most prominent class of compounds belonging to the former, whereas the latter includes many different classes of combinatorial agents that have been used to achieve synergistic efficacy against cancer. Safe delivery and accumulation at the tumor site is of paramount importance for MTIs because inhibition of multiple key signaling pathways has the potential to lead to systemic toxicity. For this reason, the development of drug delivery mechanisms using nanotechnology is preferable in order to ensure that the MDIs accumulate in the tumor vasculature, thereby increasing efficacy and minimizing off-target and systemic side effects. This review will discuss how nanotechnology can be used for the development of MTIs for cancer therapy and also it concludes with a discussion of the future of nanoparticle-based MTIs as well as the continuing obstacles being faced during the development of these unique agents.’