Targeted therapy and immunotherapy: Emerging biomarkers in metastatic melanoma

Pharmacokinetics (PK) of Tiragolumab in First-in-Human Study in Patients with Mixed Solid Tumors (GO30103)

Tiragolumab is a first-in-class, fully human IgG1/kappa anti-TIGIT monoclonal antibody that blocks the binding of TIGIT to CD155 (the poliovirus receptor). We summarize the pharmacokinetics (PK) data from the phase 1a/1b GO30103 study of Q3W (every 3 weeks) sequential dosing of tiragolumab (2, 8, 30, 100, 400, 600, or 1200 mg) followed by atezolizumab (1200 mg), Q4W (every 4 weeks) sequential dosing (tiragolumab 840 mg followed by atezolizumab 1680 mg), and Q4W co-infusion (tiragolumab 840 mg plus atezolizumab 1680 mg). Serum samples were collected at multiple time points following tiragolumab and atezolizumab intravenous infusion in patients with solid tumors for PK and immunogenicity assessment. The serum PK profile of tiragolumab appeared to be biphasic, with a rapid distribution phase followed by a slower elimination phase when administered alone or in combination with atezolizumab. In phase 1a, across doses of tiragolumab ranging from 2 to 1200 mg (cycle 1), the geometric mean (GM), coefficient of variation (CV%), serum tiragolumab Cmax ranged from 0.682 to 270 µg/mL (18.6% to 36.5%) and Cmin ranged from 0.0125 to 75.3 µg/mL (0.0% to 24.2%). The GM systemic exposure (area under the plasma drug concentration-time curve, AUC0-21) ranged from 310 to 2670 µg day/mL (20.5% to 27.0%); interindividual variability in AUC0-21 ranged from 20.5% to 43.9%. Tiragolumab exposure increased in an approximately dose-proportional manner when administered alone or with atezolizumab at doses ≥100 mg. Postbaseline, 4/207 patients (1.9%) were positive for treatment-emergent antidrug antibodies (ADA) against tiragolumab, each at a single time point. Tiragolumab combined with atezolizumab demonstrated desirable PK properties, with no drug-drug interactions or immunogenicity liability. There were no meaningful differences in tiragolumab or atezolizumab exposure between the Q4W co-infusion and sequential dosing cohorts. ClinicalTrials.gov: NCT02794571 (date of registration June 6, 2016).

Phase I study of the anti-TIGIT antibody tiragolumab in combination with atezolizumab in Japanese patients with advanced or metastatic solid tumors

PURPOSE

Tiragolumab is a monoclonal antibody that binds to the inhibitory immune checkpoint TIGIT (T-cell immunoreceptor with Ig and ITIM domains). In early phase clinical trials, tiragolumab in combination with the programmed death-ligand 1-inhibitor atezolizumab was well tolerated and has demonstrated preliminary anti-tumor activity in patients with advanced/metastatic solid tumors. We report the results of a phase I study of tiragolumab plus atezolizumab in Japanese patients (jRCT2080224926).

METHODS

Japanese patients ≥ 20 years old received tiragolumab (600 mg) and atezolizumab (1200 mg) intravenously every 21 days until unacceptable toxicity or disease progression. Primary endpoints were safety and pharmacokinetic (PK) parameters of tiragolumab plus atezolizumab. Secondary endpoints were anti-tumor activity.

RESULTS

Three patients were enrolled with diagnoses of non-small cell lung cancer, pancreatic cancer, and cholangiocarcinoma. No dose-limiting toxicities were observed. Two patients experienced treatment-related adverse events (AEs) of any grade. There were no grade ≥ 3 AEs, serious AEs, AEs leading to discontinuation, modification or withdrawal of any study drug, or AEs leading to death. At cycle 1, mean PK parameters of tiragolumab were as follows: Cmax 217 μg/mL; Cmin 54.9 μg/mL; area under the concentration-time curve from 0 to the last measurable concentration, 2000 μg·day/mL; t1/2, 17.6 days. Best overall response was stable disease in two patients.

CONCLUSION

Tiragolumab plus atezolizumab was well tolerated in Japanese patients with advanced/metastatic solid tumors, and no differences in tiragolumab PK characteristics were noted between Japanese patients enrolled in this study, and non-Japanese patients enrolled in a global phase Ia/Ib study. These results may support the inclusion of Japanese patients in ongoing global phase III clinical trials.

TRIAL REGISTRATION NUMBER

jRCT2080224926.

Relatlimab: a novel drug targeting immune checkpoint LAG-3 in melanoma therapy

Relatlimab is a type of human immunoglobulin G4 monoclonal blocking antibody. It is the world's first Lymphocyte-Activation Gene-3 (LAG-3) inhibitor and the third immune checkpoint inhibitor with clinical application, following PD-1 and CTLA-4. Relatlimab can bind to the LAG-3 receptor which blocks the interaction between LAG-3 and its ligand to reduce LAG-3 pathway-mediated immunosuppression and promote T-cell proliferation, inducing tumor cell death. On 18 March 2022, the U.S. FDA approved the fixed-dose combination of relatlimab developed by Bristol Myers Squibb with nivolumab, under the brand name Opdualag for the treatment of unresectable or metastatic melanoma in adult and pediatric patients aged 12 and older. This study comprehensively describes the mechanism of action and clinical trials of relatlimab and a brief overview of immune checkpoint drugs currently used for the treatment of melanoma.

Malignant Melanoma in a Retrospective Cohort of Immunocompromised Patients: A Statistical and Pathologic Analysis

BACKGROUND

Malignant melanoma is the leading cause of death due to cutaneous malignancy. Immunocompromised individuals have an elevated risk of developing melanoma. We aimed to provide histopathologic and statistical characterization of melanoma development in immunocompromised patients.

METHODS

We reviewed our institution's databases to identify all patients with a confirmed history of immunosuppression who subsequently developed melanoma, focusing on diagnoses during the follow-up period of 2011-2019. A total of 93 patients with a combined 111 melanoma lesions were identified.

RESULTS

Common causes of immunosuppression included transplantation and lymphoproliferative disorders. Superficial spreading and lentigo malignant melanoma were the most common malignant melanoma subtypes. Median Breslow depth was 0.7 mm, and the most common primary tumor stage was T1a. Our transplant sub-cohort had an overall melanoma incidence of 0.9 per 1000 person-years (95% CI 0.66 to 1.20) and a standardized incidence ratio (SIR) of 1.53 (95% CI 1.12 to 2.04) relative to a general population cohort from the Surveillance, Epidemiology, and End Results Program (SEER).

CONCLUSIONS

We report histopathologic characteristics of immunocompromised patients developing melanoma at a large academic tertiary-care center. Differences in age, sex, time since transplantation, and transplant type may play a significant role in melanoma SIR in this patient demographic.

Vitamin D Modulates the Response of Patient-Derived Metastatic Melanoma Cells to Anticancer Drugs

Melanoma is considered a lethal and treatment-resistant skin cancer with a high risk of recurrence, making it a major clinical challenge. Our earlier studies documented that 1,25(OH)₂D₃ and its low-calcaemic analogues potentiate the effectiveness of dacarbazine and cediranib, a pan-VEGFR inhibitor. In the current study, a set of patient-derived melanoma cultures was established and characterised as a preclinical model of human melanoma. Thus, patient-derived cells were preconditioned with 1,25(OH)₂D₃ and treated with cediranib or vemurafenib, a BRAF inhibitor, depending on the BRAF mutation status of the patients enrolled in the study. 1,25(OH)₂D₃ preconditioning exacerbated the inhibition of patient-derived melanoma cell growth and motility in comparison to monotherapy with cediranib. A significant decrease in mitochondrial respiration parameters, such as non-mitochondrial oxygen consumption, basal respiration and ATP-linked respiration, was observed. It seems that 1,25(OH)₂D₃ preconditioning enhanced cediranib efficacy via the modulation of mitochondrial bioenergetics. Additionally, 1,25(OH)₂D₃ also decreased the viability and mobility of the BRAF+ patient-derived cells treated with vemurafenib. Interestingly, regardless of the strict selection, cancer-derived fibroblasts (CAFs) became the major fraction of cultured cells over time, suggesting that melanoma growth is dependent on CAFs. In conclusion, the results of our study strongly emphasise that the active form of vitamin D, 1,25(OH)₂D₃, might be considered as an adjuvant agent in the treatment of malignant melanoma.

Cold atmospheric pressure plasma treatment combined with starvation increases autophagy and apoptosis in melanoma in vitro and in vivo

Despite advances in therapy, malignant melanoma remains a fatal disease. Among several emerging approaches to combat cancer, cold atmospheric pressure plasma (CAP) has shown promising results as a novel antitumor agent in preclinical models so far. The technology mainly relies on the emittance of various reactive oxygen and nitrogen species (ROS/RNS) that are tumor-toxic at high concentrations. Moreover, malignant melanoma has a metabolic dimension that can be targeted by mild starvation. To this end, we investigated the combined effect of starvation and CAP treatment on melanoma in vitro and in vivo. In vitro, starvation+CAP led to cell morphology changes, decreased metabolic activity and increased lipid peroxidation accompanied by apoptosis and DNA fragmentation in murine B16 melanoma cells but not murine non-malignant L929 fibroblasts. This was paralleled by increased apoptosis (Bax, Bcl-2 and Caspase-3) and autophagy (Lc3 and Atg5)-related gene expression. In vivo, starvation reduced tumor burden. Combination with CAP treatment augmented this effect significantly, albeit there was no difference of combination treatment to CAP exposure alone. Interestingly, there was an overall greater increase of Lc3 and Atg5 in the tumor tissue compared to CAP exposure alone, while starvation-induced autophagy-related gene expression was similar to in the combination group. These data collectively suggest that CAP-derived ROS/RNS treatment and autophagy-induction augment antitumor effects in malignant melanoma in vitro and in vivo.

Diffusion-Weighted Imaging Combined with Perfusion-Weighted Imaging under Segmentation Algorithm in the Diagnosis of Melanoma

This study is aimed at exploring the value of magnetic resonance diffusion-weighted imaging (DWI) combined with perfusion-weighted imaging (PWI) for diagnosing melanoma under a three-dimensional (3D) hybrid segmentation algorithm. 40 patients with melanoma were collected as research objects and subjected to magnetic resonance imaging (MRI) examination. A segmentation model was constructed and the original images were input. The noise contained in the images was preprocessed and normalized, and the mixed level set segmentation was performed after linear fusion of the images. Imaging findings were analyzed to find that the combined diagnosis of DWI and PWI with a 3D hybrid segmentation algorithm had the advantage of being clear and accurate. 10 primary cases were detected, which occurred in the cerebral meninges; 30 cases of metastases occurred inside the skull, mostly adjacent to the surface of the brain. The typical T1-weighted imaging (T1WI) and T2-weighted imaging (T2WI) of melanoma showed high signal and low signal, respectively, and the enhanced scan showed obvious enhancement. Atypical melanoma was manifested variously in MRI; a few had cystic necrosis, and an enhanced scan of the solid area revealed significant enhancement. Patients with multiple metastatic melanomas mainly showed low signal on DWI, and patients with primary or single metastatic melanoma mainly showed high signal or mixed high signal. Patients with perfusion imaging showed high perfusion on PWI. The 3D hybrid segmentation algorithm helped to improve the accuracy of DWI combined with PWI in the diagnosis of melanoma. This work provided a certain reference for the clinical diagnosis of melanoma.

Low doses of niclosamide and quinacrine combination yields synergistic effect in melanoma via activating autophagy-mediated p53-dependent apoptosis

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We developed a new strategy for melanoma by using low doses of niclosamide (N) and quinacrine (QC).

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N+QC exerts anti-melanoma effect through autophagy-mediated p53-dependent apoptosis.

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The strategy is verified to be a safe, effective and universal role for other types of cancer.

Malignant melanoma is a highly aggressive, malignant, and drug-resistant tumor. It lacks an efficient treatment approach. In this study, we developed a novel anti-melanoma strategy by using anti-tapeworm drug niclosamide and anti-malarial drug quinacrine, and investigated the molecular mechanism by in vitro and in vivo assays. Meanwhile, other types of tumor cells, immortalized epithelial cells and bone marrow mesenchymal stem cells were used to evaluate the universal role of anti-cancer and safety of the strategy. The results showed, briefly, an exposure to niclosamide and quinacrine led to an increased apoptosis-related protein p53, cleaved caspase-3 and cleaved PARP and autophagy-related protein LC3B expression, and a decreased expression of autophagy-related protein p62, finally leading to cell apoptosis and autophage. After inhibiting autophagy by Baf-A1, flow cytometry and western blot showed that the expression of apoptosis-related proteins was down-regulated and the number of apoptotic cells decreased. Subsequently, in the siRNA-mediated p53 knockdown cells, the expression of apoptosis-related proteins and the number of apoptotic cells were also reduced, while the expression of autophagy-related proteins including LC3B, p62 did not change significantly. To sum up, we developed a new, safe strategy for melanoma treatment by using low doses of niclosamide and quinacrine to treat melanoma; and found a novel mechanism by which the combination application of low doses of niclosamide and quinacrine exerts an efficient anti-melanoma effect through activation of autophagy-mediated p53-dependent apoptosis. The novel strategy was verified to exert a universal anti-cancer role in other types of cancer.

SWI/SNF Chromatin Remodeling Enzymes in Melanoma

Melanoma is an aggressive malignancy that arises from the transformation of melanocytes on the skin, mucosal membranes, and uvea of the eye. SWI/SNF chromatin remodeling enzymes are multi-subunit complexes that play important roles in the development of the melanocyte lineage and in the response to ultraviolet radiation, a key environmental risk factor for developing cutaneous melanoma. Exome sequencing has revealed frequent loss of function mutations in genes encoding SWI/SNF subunits in melanoma. However, some SWI/SNF subunits have also been demonstrated to have pro-tumorigenic roles in melanoma and to affect sensitivity to therapeutics. This review summarizes studies that have implicated SWI/SNF components in melanomagenesis and have evaluated how SWI/SNF subunits modulate the response to current therapeutics.

Prophylactic vaccines against cancers of non-infectious origin: a dream or a real possibility?

The dramatic progress in tumour biology and immunology in the past several years has opened new avenues for the treatment and prevention of cancer. One of the great contributions of the immunotherapeutic approaches is an increasing understanding of the immunology of cancer, which is, gradually creating conditions for the development of prophylactic anti-cancer vaccines. Efficient vaccines have been developed and employed for the prophylaxis of two frequent cancers of viral origin, namely cervical cancer and liver cancer. The new knowledge on the interactions between the immune system and the malignant tumors seems to provide means for the development of prophylactic vaccines against cancers developing due to the mutations in the proto-oncogenes converting their products into oncoproteins. According to the present estimates, these cancers form a great majority of human malignancies. Recent evidence has indicated that the immune system recognizes such mutated proteins, and that the development of cancer is due to the failure of the immune system to eliminate neoplastic cells. Followingly, it can be expected that inducing immunity against the mutated epitopes will increase the capacity of the body to deal with the initiated precancerous cells. In the present paper this hypothesis is primarily discussed in the relationship with colorectal cancer (CRC), which seems to be a well-fitting candidate for prophylactic vaccination. CRC is the third most frequent malignancy and the fourth most common cause of cancer mortality. Mutations of two proto-oncogenes, namely RAS and RAF, are involved in the majority of CRC cases and, in addition, they are shared with other human malignancies. Therefore, the strategy to be used for prophylaxis of CRC is discussed together with several other frequent human cancers, namely lung cancer, pancreatic duct cancer and melanoma. The prophylactic vaccines proposed are aimed at the reduction of the incidence of these and, to a lesser extent, some other cancers.

uPAR+ extracellular vesicles: a robust biomarker of resistance to checkpoint inhibitor immunotherapy in metastatic melanoma patients

Background

Emerging evidence has highlighted the importance of extracellular vesicle (EV)-based biomarkers of resistance to immunotherapy with checkpoint inhibitors in metastatic melanoma. Considering the tumor-promoting implications of urokinase-type plasminogen activator receptor (uPAR) signaling, this study aimed to assess uPAR expression in the plasma-derived EVs of patients with metastatic melanoma to determine its potential correlation with clinical outcomes.

Methods

Blood samples from 71 patients with metastatic melanoma were collected before initiating immunotherapy. Tumor-derived and immune cell-derived EVs were isolated and analyzed to assess the relative percentage of uPAR⁺ EVs. The associations between uPAR and clinical outcomes, sex, BRAF status, baseline lactate dehydrogenase levels and number of metastatic sites were assessed.

Results

Responders had a significantly lower percentage of tumor-derived, dendritic cell (DC)-derived and CD8⁺ T cell-derived uPAR +EVs at baseline than non-responders. The Kaplan-Meier survival curves for the uPAR⁺EV quartiles indicated that higher levels of melanoma-derived uPAR⁺ EVs were strongly correlated with poorer progression-free survival (p<0.0001) and overall survival (p<0.0001). We also found a statistically significant correlation between lower levels of uPAR⁺ EVs from both CD8⁺ T cells and DCs and better survival.

Conclusions

Our results indicate that higher levels of tumor-derived, DC-derived and CD8⁺ T cell-derived uPAR⁺ EVs in non-responders may represent a new biomarker of innate resistance to immunotherapy with checkpoint inhibitors. Moreover, uPAR⁺ EVs represent a new potential target for future therapeutic approaches.

Thinking Small: Small Molecules as Potential Synergistic Adjuncts to Checkpoint Inhibition in Melanoma

Metastatic melanoma remains the deadliest form of skin cancer. Immune checkpoint inhibition (ICI) immunotherapy has defined a new age in melanoma treatment, but responses remain inconsistent and some patients develop treatment resistance. The myriad of newly developed small molecular (SM) inhibitors of specific effector targets now affords a plethora of opportunities to increase therapeutic responses, even in resistant melanoma. In this review, we will discuss the multitude of SM classes currently under investigation, current and prospective clinical combinations of ICI and SM therapies, and their potential for synergism in melanoma eradication based on established mechanisms of immunotherapy resistance.

An Update on the Role of Ubiquitination in Melanoma Development and Therapies

The ubiquitination system plays a critical role in regulation of large array of biological processes and its alteration has been involved in the pathogenesis of cancers, among them cutaneous melanoma, which is responsible for the most deaths from skin cancers. Over the last decades, targeted therapies and immunotherapies became the standard therapeutic strategies for advanced melanomas. However, despite these breakthroughs, the prognosis of metastatic melanoma patients remains unoptimistic, mainly due to intrinsic or acquired resistances. Many avenues of research have been investigated to find new therapeutic targets for improving patient outcomes. Because of the pleiotropic functions of ubiquitination, and because each step of ubiquitination is amenable to pharmacological targeting, much attention has been paid to the role of this process in melanoma development and resistance to therapies. In this review, we summarize the latest data on ubiquitination and discuss the possible impacts on melanoma treatments.

Biologic subtypes of melanoma predict survival benefit of combination anti-PD1+anti-CTLA4 immune checkpoint inhibitors versus anti-PD1 monotherapy

Purpose

Anti-programmed cell death protein 1 (PD1)±anti-cytotoxic T-lymphocyte associated protein 4 (CTLA4) immune checkpoint inhibitors (ICIs) are standard therapeutic options for metastatic melanoma. We assessed whether biologic subtype according to primary tumor type or genomic subtype can function as predictive biomarkers for anti-PD1±anti-CTLA4 ICI in patients with advanced melanoma.

Methods

We performed a single-center retrospective cohort analysis of patients who received anti-PD1±anti-CTLA4 ICI for advanced melanoma between 2012 and 2019. Primary tumor type, BRAF and NRAS mutation status, and other covariates were abstracted from chart review. Log-rank tests and multivariable Cox regression models were used to assess differences in clinical progression-free (cPFS) and overall survival (OS).

Results

We identified 230 patients who received 249 lines of anti-PD1±anti-CTLA4 ICI for unresectable or metastatic disease. Of these patients, 74% were cutaneous, 11% mucosal, 8% unknown primary and 7% acral. BRAF and NRAS mutations were identified in 35% and 28% of patients, respectively. In multivariable analyses of the entire cohort, acral or mucosal primary tumor type, >3 metastatic sites, elevated LDH were predictive of shorter cPFS and OS. Combination ICI therapy was associated with longer cPFS (HR 0.57, 95% CI 0.38 to 0.86, p=0.007) and OS (HR 0.42, 95% CI 0.28 to 0.65, p<0.001). Combination ICI was significantly associated with longer OS in unknown primary and mucosal melanoma. There was a non-significant trend toward longer OS with anti-PD1+anti-CTLA4 in cutaneous melanoma, but not in acral melanoma. In multivariable analyses, combination ICI was associated with longer OS in NRAS (HR 0.24, 95% CI 0.10 to 0.62, p=0.003, n=69) and BRAF V600E/K (HR 0.47, 95% CI 0.24 to 0.90, p=0.024, n=86) mutant melanoma but not BRAF/NRAS wild-type (n=94) melanoma.

Conclusions

In our cohort, primary melanoma tumor type and genomic subtype were independent predictive markers of cPFS and OS for patients with metastatic melanoma receiving anti-PD1 ICI. Primary tumor type and genomic subtype—including NRAS—should be further evaluated in prospective clinical trials to determine their value as predictive markers. Biologic subtypes may facilitate clinical decision-making when recommending combination ICI treatment (anti-PD1±anti-CTLA4) versus anti-PD1 alone for patients with metastatic melanoma.

Immunotyping and Quantification of Melanoma Tumor-Infiltrating Lymphocytes

The density of tumour-infiltrating lymphocytes (TILs) in melanoma is correlated with improved clinical prognosis; however, standardized TIL immunotyping and quantification protocols are lacking. Herein, we provide a review of the technologies being utilized for the immunotyping and quantification of melanoma TILs.

ARID2 Deficiency Correlates with the Response to Immune Checkpoint Blockade in Melanoma

The SWI/SNF chromatin remodeler family includes the BAF and PBAF complexes. ARID2, encoding a PBAF complex subunit, is frequently mutated in melanoma independently of BRAF/RAS mutations. Emerging evidence shows that SWI/SNF complexes regulate tumor immunity; for instance, the loss of PBRM1, another PBAF complex subunit, enhances susceptibility to immune checkpoint inhibitors in melanoma. Notably, ARID2 mutations are more frequent in melanoma than PBRM1 mutations. However, the role of ARID2 as a modulator of tumor immunity remains unclear. In this study, we show that ARID2 knockout sensitizes melanoma to immune checkpoint inhibitors. Anti‒PD-L1 treatment restricts tumor growth in mice bearing ARID2-knockout melanoma cells, correlating with an increase in the infiltration of cytotoxic CD8⁺ T cells. Furthermore, ARID2 deficiency leads to signal transducer and activator of transcription 1 upregulation, which subsequently causes increased expression of T-cell‒attracting chemokines such as CXCL9, CXCL10, and CCL5. These results demonstrate that ARID2 is an immunomodulator and a potential biomarker that indicates immune checkpoint inhibitor effectiveness in patients with melanoma.

17-Aminogeldanamycin Inhibits Constitutive Nuclear Factor-Kappa B (NF-κB) Activity in Patient-Derived Melanoma Cell Lines

Melanoma remains incurable skin cancer, and targeting heat shock protein 90 (HSP90) is a promising therapeutic approach. In this study, we investigate the effect of 17-aminogeldanamycin, a potent HSP90 inhibitor, on nuclear factor-kappa B (NF-κB) activity in BRAF^V600E and NRAS^Q61R patient-derived melanoma cell lines. We performed time-lapse microscopy and flow cytometry to monitor changes in cell confluence and viability. The NF-κB activity was determined by immunodetection of phospho-p65 and assessment of expression of NF-κB-dependent genes by quantitative real-time polymerase chain reaction (qRT-PCR), Western blotting, and enzyme-linked immunosorbent assay (ELISA). Constitutive activity of p65/NF-κB was evident in all melanoma cell lines. Differences in its level might be associated with genetic alterations in CHUK, IL1B, MAP3K14, NFKBIE, RIPK1, and TLR4, while differences in transcript levels of NF-κB-inducible genes revealed by PCR array might result from the contribution of other regulatory mechanisms. 17-Aminogeldanamycin markedly diminished the level of phospho-p65, but the total p65 protein level was unaltered, indicating that 17-aminogeldanamycin inhibited activation of p65/NF-κB. This conclusion was supported by significantly reduced expression of selected NF-κB-dependent genes: cyclin D1 (CCND1), C-X-C motif chemokine ligand 8 (CXCL8), and vascular endothelial growth factor (VEGF), as shown at transcript and protein levels, as well as secretion of IL-8 and VEGF. Our study indicates that 17-aminogeldanamycin can be used for efficient inhibition of NF-κB activity and the simultaneous diminution of IL-8 and VEGF levels in the extracellular milieu of melanoma.