Primary Melanoma Tumors Research Articles

Desmosome mutations impact the tumor microenvironment to promote melanoma proliferation.

Desmosomes are transmembrane protein complexes that contribute to cell-cell adhesion in epithelia and other tissues. Here, we report the discovery of frequent genetic alterations in the desmosome in human cancers, with the strongest signal seen in cutaneous melanoma where desmosomes are mutated in >70% of cases. In primary but not metastatic melanoma biopsies, the burden of coding mutations in desmosome genes associates with a strong reduction in desmosome gene expression. Analysis by spatial transcriptomics and protein immunofluorescence suggests that these expression decreases occur in keratinocytes in the microenvironment rather than in primary melanoma cells. In further support of a microenvironmental origin, we find that desmosome gene knockdown in keratinocytes yields markedly increased proliferation of adjacent melanoma cells in keratinocyte/melanoma co-cultures. Similar increases in melanoma proliferation are observed in media preconditioned by desmosome-deficient keratinocytes. Thus, gradual accumulation of desmosome mutations in neighboring cells may prime melanoma cells for neoplastic transformation.

BRAF and NRAS Mutations and the Association with Prognosis of Acral Lentiginous and Nodular Melanomas in Indonesia.

Melanomas are rare yet the most aggressive skin cancer among Asians. Clinical presentation, risk factors, and the underlying molecular mechanisms are strikingly different from cutaneous melanoma in Caucasians. Mutation patterns of BRAF and NRAS genes were examined from DNAs derived from primary melanoma tumor tissues (fresh tissues or formalin-fixed paraffin-embedded samples) using pyrosequencing. A total of 63 patients consisting of acral lentiginous melanoma (N=22, 34.9%) and nodular melanoma (N=41, 65.1%) were included in this study. Most patients were diagnosed at Stage III-IV (N=49, 77.8%), Breslow thickness more than 4 mm (N=51, 80.9%), presence of ulceration (N=35, 55.6%), diameter larger than 6 mm (N=61, 96.8%), regional node infiltration (N=41, 77.8%). BRAF and NRAS mutations were found in 28 (44.4%) and 8 (12.7%), respectively. BRAF and NRAS mutations were significantly associated with older melanoma patients (OR = 6.075, 95%CI = 2.013-18.333 dan OR = 13.263, 95%CI = 1.518-115.901, respectively). BRAF mutations were associated with lower overall survival (Median survivals were 16.5 vs 31.4 months, Log-rank test P=0.001). NRAS mutations were not significantly associated with lower overall survival. In this study, melanoma patients are largely diagnosed at the late stages with ulceration and involvement of regional lymph nodes. BRAF mutations are associated with lower survival of cutaneous melanoma patients.

Detection of neoplastic-immune hybrid cells with metastatic properties in uveal melanoma

BackgroundUveal melanoma is the most common non-cutaneous melanoma and is an intraocular malignancy affecting nearly 7,000 individuals per year worldwide. Of these, approximately 50% will progress to metastatic disease for which there are currently no effective curative therapies. Despite advances in molecular profiling and metastatic stratification of uveal melanoma tumors, little is known regarding their underlying biology of metastasis. Our group has identified a disseminated neoplastic cell population characterized by co-expression of immune and melanoma proteins, circulating hybrid cells (hybrids), in patients with uveal melanoma. Compared to circulating tumor cells, which lack expression of immune proteins, hybrids are detected at an increased prevalence in peripheral blood and can be used as a non-invasive biomarker to predict metastatic progression.MethodsTo ascertain mechanisms underlying enhanced hybrid cell dissemination we identified hybrid cells within primary uveal melanoma tumors using single cell RNA sequencing (n = 8) and evaluated their gene expression and predicted ligand-receptor interactions in relation to other melanoma and immune cells within the primary tumor. We then verified expression of upregulated hybrid pathways within patient-matched tumor and peripheral blood hybrids (n = 4) using cyclic immunofluorescence and quantified their protein expression relative to other non-hybrid tumor and disseminated tumor cells.ResultsAmong the top upregulated genes and pathways in hybrid cells were those involved in enhanced cell motility and cytoskeletal rearrangement, immune evasion, and altered cellular metabolism. In patient-matched tumor and peripheral blood, we verified gene expression by examining concordant protein expression for each pathway category: TMSB10 (cell motility), CD74 (immune evasion) and GPX1 (metabolism). Both TMSB10 and GPX1 were expressed on significantly higher numbers of disseminated hybrid cells compared to circulating tumor cells, and CD74 and GPX1 were expressed on more disseminated hybrids than tumor-resident hybrids. Lastly, we identified that hybrid cells express ligand-receptor signaling pathways implicated in promoting metastasis including GAS6-AXL, CXCL12-CXCR4, LGALS9-P4HB and IGF1-IGFR1.ConclusionThese findings highlight the importance of TMSB10, GPX1 and CD74 for successful hybrid cell dissemination and survival in circulation. Our results contribute to the understanding of uveal melanoma tumor progression and interactions between tumor cells and immune cells in the tumor microenvironment that may promote metastasis.

Characterization of innate lymphoid cell subsets infiltrating melanoma and epithelial ovarian tumors

ABSTRACT The innate lymphoid cell (ILC) family is composed of heterogeneous innate effector and helper immune cells that preferentially reside in tissues where they promote tissue homeostasis. In cancer, they have been implicated in driving both pro- and anti-tumor responses. This apparent dichotomy highlights the need to better understand differences in the ILC composition and phenotype within different tumor types that could drive seemingly opposite anti-tumor responses. Here, we characterized the frequency and phenotype of various ILC subsets in melanoma metastases and primary epithelial ovarian tumors. We observed high PD-1 expression on ILC subsets isolated from epithelial ovarian tumor samples, while ILC populations in melanoma samples express higher levels of LAG-3. In addition, we found that the frequency of cytotoxic ILCs and NKp46+ILC3 in tumors positively correlates with monocytic cells and conventional type 2 dendritic cells, revealing potentially new interconnected immune cell subsets in the tumor microenvironment. Consequently, these observations may have direct relevance to tumor microenvironment composition and how ILC subset may influence anti-tumor immunity.

EVALUATION OF THE CYTOTOXICITY AND GENOTOXICOLOGICAL SAFETY PROFILE OF BIOACTIVE SILVER(I) COMPLEXES WITH AMINOADAMANTANE LIGANDS

Silver(I) complexes of amantadine (atdH), memantine (mtnH) and rimantadine (rtdH), named Ag-atd, Ag-mtn and Ag-rtd, respectively, were recently synthesized and described in the literature as promising antibacterial agents. In the present study, the cytotoxicity of such complexes was evaluated against cultures of primary epidermal keratinocytes (HaCaT) and murine melanoma tumor cells (B16-F10), and mutagenicity was studied by the Ames test to investigate their abilities to induce gene mutations. The Ames test was performed using Salmonella Typhimurium strains (TA98, TA100, TA102 and TA97a) capable of detecting frameshift and base pair substitution gene mutations, in experiments with and without metabolic activation (microsomal fraction S9). This study revealed significant cytotoxic activity against tumor cells and selectivity of Ag-atd and Ag-rtd complexes when compared to non-tumor human keratinocyte cells. Moreover, the Ag(I) complexes did not induce a significant growth in the number of revertant colonies when comparing with the negative control, both in the experiments without and with metabolic activation, indicating absence of mutagenic activity. The results are encouraging and collaborate in the genotoxicological investigations necessary for understanding the interaction and ability of the silver complexes to induce mutations and contribute to ensure their uses as future antibacterial or antitumor agents.

Tumor infiltrating lymphocyte (TIL) harvest and ex vivo expansion from primary and metastatic (met) uveal melanoma (UM) tumors.

9513 Background: Adoptively transferred autologous cell therapy using tumor-infiltrating lymphocytes (TIL) is an emerging treatment for met melanoma. Responses have been seen in patients (pts) with checkpoint inhibitor-naïve and -refractory cutaneous melanoma. UM represents a disease subtype that is traditionally less responsive to immune checkpoint blockade (ICB). Preliminary studies have shown clinical utility of TIL in UM pts. However, data describing the success rates of TIL harvest and ex vivo expansion of cells from primary and met UM tumors, and of the treatment of pts with met UM, is limited. Methods: Between 2004 and 2019, we conducted a single-center IRB-approved trial (NCT NCT00338377) for TIL harvest in pts age 18 and older with documented met melanoma, including UM pts. The protocol was amended to allow harvest of primary UM tumors in 2015 if the pt was dispositioned for enucleation as primary treatment. Results: A total of 96 UM pts underwent TIL harvest; 9 underwent treatment with TIL. Median age was 54 years (range: 28 – 86); 56% of the pts were male; 78% were Caucasian, 9% Hispanic, and 13% unknown ethnicity. Overall successful ex vivo expansion of TIL occurred in 34.8% (32/92) of UM tumors in typical tumor fragment culture with IL-2 (TIL 1.0), with higher rates observed with UM mets (29/65; 44.6%) than UM primary tumors (3/27; 11.1%). Better results were observed with a culture method (TIL 3.0) that includes agonistic stimulation of CD3 and 41BB, with 96.8% (30/31 tumors). Expansion using this new method was successful in 9/10 primary UM tumors and 21/21 UM mets. Average number of days in culture for successful initial ex vivo expansion was 33.0 days for TIL 1.0 and 17.9 days for TIL 3.0 ( p-value<0.0001). Overall, the average number of TIL expanded from culture and cryopreserved for clinical use was 130.4 million for TIL 1.0 (range: 34-460) and 326.2 million for TIL 3.0 (range 102-760) ( p-value<0.0001). Nine met UM pts received treatment with up to 150 x 109 post-Rapid Expansion Protocol (REP) TIL (5 TIL 1.0, 4 TIL 3.0). Median age was 53, 44% were male, and all had active liver mets with a median of 3 lines of prior treatment for advanced disease. 8 of the TIL products were from UM mets (4 soft tissue, 3 liver, 1 combination of soft tissue and liver tumors), and 1 was from primary UM tumor, for which TIL could only be expanded with TIL 3.0. Best overall response rate per immune-related response criteria was 22% partial response (PR, duration of response was 22.1 months and 16.5 months), 44% stable disease (SD), and 33% progression of disease (PD) for a disease control rate of 66% (PR + SD). Both responding pts had TIL harvests from mets and had previously progressed on ICB, one was treated with TIL 3.0. Conclusions: TIL harvest and successful ex vivo expansion of cells is possible from both primary and met UM with TIL 3.0 culture method and can be therapeutically effective. Clinical trial information: NCT00338377 .

Photothermal-triggered dendrimer nanovaccines boost systemic antitumor immunity.

Tumor vaccine that can effectively activate or strengthen the body's antitumor immune response to kill and eliminate tumor cells has attracted widespread attention. Currently developed tumor vaccines have severe shortcomings such as low bioavailability and lack of dual or multiple functions, resulting in poor antitumor efficacy. Herein, we report the development of an advanced nanosystem integrated with phenylboronic acid (PBA)-functionalized poly(amidoamine) dendrimers of generation 5 (G5), copper sulfide nanoparticles, and cyclic GMP-AMP (cGAMP), an immune adjuvant (for short, G5-PBA@CuS/cGAMP) to act as a photothermal-triggered nanovaccine. We show that the prepared functional nanosystem possesses an average CuS core size of 3.6nm, prominent near-infrared absorption feature to have an excellent photothermal conversion efficiency of 44.0%, and good protein adsorption characteristics due to the PBA modification. With these features, the developed nanosystem can be adopted for photothermal therapy of primary melanoma tumors and simultaneously absorb the whole tumor cell antigens, thus creating photothermal-triggered dendrimeric nanovaccine of G5-PBA@CuS/cGAMP/antigen in situ to induce antitumor immune response to inhibit the distal tumors as well. Meanwhile, melanoma cells treated with the G5-PBA@CuS in vitro under laser irradiation allowed the creation of G5-PBA@CuS/antigen complexes that could be further integrated with cGAMP to form preformed nanovaccine for effective primary tumor inhibition and tumor occurrence prevention. The designed photothermal-triggered dendrimeric nanovaccine may represent an advanced nanomedicine formulation to effectively inhibit the growth of primary and distal tumors, and prevent tumor occurrence through the stimulated systemic antitumor immunity.

Physical- and Chemical-Dually ROS-Responsive Nano-in-Gel Platforms with Sequential Release of OX40 Agonist and PD-1 Inhibitor for Augmented Combination Immunotherapy.

Combination immunotherapy synergizing the PD-1 blockade with OX40 agonism has become a research hotspot, due to its enormous potential to overcome the restricted clinical objective response suffered by monotherapy. Questions of timing and sequence have been important aspects of immunotherapies when considering immunologic mechanisms; however, most of the time the straightforward additive approach was taken. Herein, our work is the first to investigate an alternative timing of aOX40 and aPD-1 treatment in melanoma-bearing mice, and it demonstrates that sequential administration (aOX40 first, then aPD-1 following) provided superior antitumor benefits than concurrent treatment. Based on that, to further avoid the limits suffered by solution forms, we adopted pharmaceutical technologies to construct an in situ-formed physical- and chemical-dually ROS-responsive nano-in-gel platform to implement sequential and prolonged release of aPD-1 and aOX40. Equipped with these advantages, the as-prepared (aPD-1NCs&aOX40)@Gels elicited augmented combination immunity and achieved great eradication of both primary and distant melanoma tumors in vivo.

LAP1 supports nuclear adaptability during constrained melanoma cell migration and invasion

Metastasis involves dissemination of cancer cells away from a primary tumour and colonization at distal sites. During this process, the mechanical properties of the nucleus must be tuned since they pose a challenge to the negotiation of physical constraints imposed by the microenvironment and tissue structure. We discovered increased expression of the inner nuclear membrane protein LAP1 in metastatic melanoma cells, at the invasive front of human primary melanoma tumours and in metastases. Human cells express two LAP1 isoforms (LAP1B and LAP1C), which differ in their amino terminus. Here, using in vitro and in vivo models that recapitulate human melanoma progression, we found that expression of the shorter isoform, LAP1C, supports nuclear envelope blebbing, constrained migration and invasion by allowing a weaker coupling between the nuclear envelope and the nuclear lamina. We propose that LAP1 renders the nucleus highly adaptable and contributes to melanoma aggressiveness.

Running to Outcompete Metastasis.

The role of exercise in cancer progression is an emerging field of research, with intriguing evidence for physical activity playing an inhibitory role in cancer onset. In their recent publication, Sheinboim and colleagues demonstrate the impact of physical exercise on melanoma primary tumor growth and metastasis. They establish that physical exercise decreases metastatic spread, using both human epidemiologic data and in vivo models of melanoma metastasis. Systemic metabolic reprogramming of organs, induced by exercise, leads to a decrease in melanoma growth and progression as healthy organs are able to outcompete melanoma cells for nutrients. Exercise led to systemic metabolic changes in carbohydrate metabolism, glycolysis, and oxidative phosphorylation as well as mitochondrial biogenesis. Interestingly, the "metabolic shield" created by exercise could be reversed using the mTOR inhibitor rapamycin. This study highlights the importance of metabolic plasticity in metastasis and uncovers a direct link between systemic metabolic reprogramming and mTOR signaling. Overall, the study by Sheinboim and colleagues provides a more detailed understanding of the metastatic requirements in the context of energy and nutrient availability and the impact of exercise on cancer progression, highlighting novel opportunities for therapeutic intervention. See related article by Sheinboim et al., p. 4164.

Selected Articles from This Issue

Highlights| October 04 2022 Selected Articles from This Issue Author & Article Information Online ISSN: 1557-3125 Print ISSN: 1541-7786 ©2022 American Association for Cancer Research2022American Association for Cancer Research Mol Cancer Res (2022) 20 (10): 1469. https://doi.org/10.1158/1541-7786.MCR-20-10-HI Related Content A commentary has been published: Intronic Cis-Element DR8 in hTERT Is Bound by Splicing Factor SF3B4 and Regulates hTERT Splicing in Non–Small Cell Lung Cancer A commentary has been published: Distinct Transcriptional Programs in Ascitic and Solid Cancer Cells Induce Different Responses to Chemotherapy in High-Grade Serous Ovarian Cancer A commentary has been published: TRAF4 Inhibits Bladder Cancer Progression by Promoting BMP/SMAD Signaling View more A commentary has been published: EPAC Regulates Melanoma Growth by Stimulating mTORC1 Signaling and Loss of EPAC Signaling Dependence Correlates with Melanoma Progression View less Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Cite Icon Cite Search Site Article Versions Icon Versions Version of Record October 4 2022 Citation Selected Articles from This Issue. Mol Cancer Res 1 October 2022; 20 (10): 1469. https://doi.org/10.1158/1541-7786.MCR-20-10-HI Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest Search Advanced Search Cutaneous melanoma metastasis begins with lymphatic invasion, followed by hematogenous dissemination and distant organ metastasis. While Rodríguez, Castro Pérez, Setaluri, and co-authors have shown that exchange protein directly activated by cAMP (EPAC) drives growth and survival in primary melanoma tumors but not metastatic lesions, underlying signaling dynamics remain unclear. In this study, the investigators used genetically matched primary and metastatic melanoma cells and pharmacological and genetic EPAC modulation to query EPAC-regulated signaling in each case. The authors found that a pharmacological EPAC inhibitor, ESI-09, abrogates expression of cyclins, cyclin-dependent kinases (CDK), and CDK inhibitors uniquely in primary melanoma cells, and correspondingly disrupts cell cycle progression only in primary melanoma cells. Mechanistically, the authors demonstrated that while EPAC-mediated RAP1 activation and EPAC subcellular localization are similar in primary and metastatic melanoma cells, EPAC inhibition affects AKT and mTORC1 signaling and downstream metabolic features in primary but not metastatic cells. All together,... You do not currently have access to this content.

Abstract SY24-04: And by a sleep to say we end: Tumor dormancy, aging, and recurrent disease

Abstract Disseminated cancer cells (DCCs) that escape the primary site can seed in distal tissues, but may take several years, or even decades to grow out into overt metastases, a phenomenon termed tumor dormancy. Despite its importance in metastasis and residual disease, few studies have been able to successfully model or characterize dormancy within melanoma. Here, we show that age-related changes in the lung microenvironment facilitate a permissive niche for efficient outgrowth of disseminated dormant tumor cells, in contrast to the aged skin, where age-related changes suppress melanoma growth but drive dissemination. A model of melanoma progression that addresses these microenvironmental complexities is the phenotype switching model, which argues that melanoma cells switch between a proliferative cell state and a slower-cycling, invasive state. We have previously shown that dermal fibroblasts are key orchestrators of promoting phenotype switching in primary melanoma tumors via changes in the secretion of soluble factors during aging. Our new data identify Wnt5A as a master regulator of activating melanoma DCC dormancy within the lung, which initially enables efficient dissemination and seeding of melanoma cells in metastatic niches. Age-induced reprogramming of lung fibroblasts increases their secretion of soluble Wnt factors enabling efficient metastatic outgrowth. Overall, we find that age-induced changes in distal metastatic microenvironments promotes efficient reactivation of dormant melanoma cells in the lung. Further these changes are also reflected in the response of tumor cells to therapy, linking dormancy to recurrent disease. Citation Format: Ashani T. Weeraratna. And by a sleep to say we end: Tumor dormancy, aging, and recurrent disease [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr SY24-04.

Abstract 354: A tissue microarray study to validate key immune-related proteins in melanoma

Abstract New immunomodulatory therapeutic targets and prognostic biomarkers hold promise in the management of melanoma. Using publicly available human melanoma datasets and bioinformatics analyses, we previously identified 21 immune-related genes that are differentially expressed in metastatic melanoma and have significant association with patient survival (Cancer Res 2021;81(13 Suppl):Abstract 873). Further, we shortlisted five candidate genes that have been implicated in pathogenesis of certain cancers; however, their role in melanoma is not known. These include, (i) Marginal Zone B and B1 cell specific protein (MZB1), an endoplasmic reticulum (ER)-localized protein that is shown to constitutively express in B cells as well as on cancer cells; (ii) SAM Domain, SH3 Domain and Nuclear Localization Signals 1 (SAMSN1), a negative regulator of B-cell activation that regulates cell spreading and cell polarization; (iii) NCK Associated Protein 1 Like (NCKAP1L) that controls lymphocyte development, activation, and proliferation, as well as phagocytosis and migration by neutrophils and macrophages; (iv) Kallikrein Related Peptidase 8 (KLK8), an epidermal protease involved in the skin barrier proteolytic cascade; and (v) Epstein Barr Virus Induced Gene 3 (EBI3) functions in innate immune responses. This study was aimed to validate the expression profile of these five proteins (MZB1, SAMSN1, NCKAP1L, KLK8 and EBI3) in clinical melanoma tissues along with S100, a melanoma biomarker. We performed fluorescent immunostaining of a human melanoma tissue microarray (ME2082c; US Biomax) consisting of 208 melanoma tissue cores (128 cases of primary malignant melanoma, 64 metastatic melanoma, 8 adjacent skin and 8 normal skin tissue) followed by multispectral Vectra Imaging coupled with inForm software analysis. Our results showed significantly increased expression of KLK8, SAMSN1 and EBI3 in S100-positive melanoma cells compared to S100-negative cells. Further, MZB1 and NCKAP1L protein levels were significantly increased in melanoma primary tumors and metastatic tissues compared to normal skin. Furthermore, an increasing trend for KLK8 and SAMSN1 proteins, though not significant, was observed in melanoma tissues. Interestingly, EBI3 expression was not found to be altered between the melanoma and skin tissues. Next, using in vitro cell culture analysis, we quantified MZB1 protein levels using Simple Western in various human melanoma cell lines and normal human melanocytes. We observed increased MZB1 protein levels in four human melanoma cell lines (A375, G361, HS294T, WM115) compared to normal melanocytes. Overall, our study suggests that MZB1 and NCKAP1L could be potential new targets for melanoma management. Additional validation and further evaluation of functional significance of these immune-related proteins using in vitro and in vivo models may lead to new prognostic and therapeutic strategies for melanoma management. Citation Format: Gagan Chhabra, Jessica Thornton, Shengqin Su, Mary A. Ndiaye, Nihal Ahmad. A tissue microarray study to validate key immune-related proteins in melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 354.

Abstract 976: Interrogating the pre-metastastic gene signature to block brain metastases

Abstract BACKGROUND: The incidence of brain metastases (BM) is tenfold higher than that of primary brain tumors. BM predominantly originate from primary lung, breast, and melanoma tumors with a 90% mortality rate within one year of diagnosis, posing a large unmet clinical need to identify novel therapies against BM. The goal of this work is to uncover the molecular factors that drive the formation of BM and investigate whether we can slow down and ultimately block BM formation. METHODS: The Singh lab has generated a large in-house biobank of patient-derived BM cell lines that are established from BM patient tumor samples. We use these BM cell lines to generate murine orthotopic xenograft models of BM and interrogate the biological processes that lead to BM. These models have successfully recapitulated all the stages of their respective BM cascades and additionally captured a “pre-metastatic” population of BM cells that have just seeded the brains of mice before forming mature, clinically detectable tumors. Pre-metastatic cell populations are impossible to detect in human patients but represent a therapeutic window wherein metastasizing cells can be targeted and eradicated before establishing clinically detectable and difficult to treat brain tumors. RESULTS: RNA sequencing of pre-metastatic BM cells revealed a unique deregulated transcriptomic profile that is specific to pre-metastatic cells despite the tumor of origin. Subsequent Connectivity Map analysis revealed compounds that we biologically characterized in vitro for selective anti-BMIC phenotypes. This effort led to a lead compound that exhibits anti-BM activity in vitro, while remaining ineffective against normal brain cell controls. Preliminary in vivo work has shown that following both orthotopic and intracardiac injection of BM cells, treatment with this lead compound reduces the tumor burden compared to mice being treated by a vehicle control, while providing a significant survival advantage. Ongoing mechanistic investigations aim to delineate the protein target of this compound in the context of the observed selective anti-BM phenotype. CONCLUSION: Identification of novel small molecules that target premetastatic BM cells could slow or prevent the formation of BM and dramatically improve the prognosis of at-risk cancer patients. Citation Format: Agata Kieliszek, Blessing Bassey-Archibong, Chitra Venugopal, Sheila Singh. Interrogating the pre-metastastic gene signature to block brain metastases [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 976.

An 11-gene expression signature related to tumorigenesis and immunosuppression in primary cutaneous melanoma predicts sentinel lymph node metastatic status.

e21579 Background: A biomarker derived from the primary melanoma tumor to predict regional sentinel lymph node (SLN) metastatic status can be valuable in guiding the decision making in planning the SLN surgical procedure for candidate patients. Methods: Gene expression profiling was performed on primary cutaneous melanoma tumor biopsies of 49 (24 known SLN+, 25 SLN-) patients (T3a/b, T4a/b) who underwent SLN for staging using transcriptome profiling analysis. U133A 2.0 Affymetrix gene chips were used. Significance Analysis of Microarrays (SAM) was used to test the association between gene expression level of the primary tumor and SLN status. Genes with fold change > 1.5 and q value < 0.05 were considered differentially expressed. Pathway analysis was performed using Ingenuity Pathway Analysis. Benjamini and Hochberg method was used to adjust for multiple testing in pathway analysis. All statistical analyses were implemented in R. Results: A total of 49 patients with primary cutaneous melanoma were studied, of which, 24 were diagnosed as SLN positive and 25 as SLN negative by routine H&E and immunohistochemistry. Using SLN metastatic status as the outcome, a univariate logistic regression model was fitted with individual probe sets. A total of 251 probe sets were filtered and 11 probe sets were considered as differentially expressed (DE) between SLN-ve and SLN+ve groups, with the selection criterion set at Benjamini- Hochberg method -adjusted p -value below 0.05 and the absolute log fold change above 0.5. As each of the 11 probe sets was matched to a unique known gene, an 11 gene signature was derived and among them, the expression level of 7 genes was significantly reduced in the SLN+ve group compared to the SLN-ve group, while 4 genes were overexpressed in the SLN+ve group. Integrative and interactive heatmaps were produced from hierarchical cluster analysis to show the 11 differentially expressed genes. Selected genes were found to be uniformly related to tumorigenesis, malignant progression, DNA repair, cell cycle regulation, chemoresistance, immunosuppression and/or involvement in multiple cancer-related pathways. Several of the selected genes were previously shown to be prognostic in various malignancies. Conclusions: We present a unique 11-gene expression signature derived from primary melanoma tumor biopsy samples and related to tumorigenesis and immunosuppression that may be useful for the prognostic stratification of melanoma patients. This may allow the optimal selection of patients for SLN biopsy.

Translating Molecules into Imaging-The Development of New PET Tracers for Patients with Melanoma.

Melanoma is a deadly disease that often exhibits relentless progression and can have both early and late metastases. Recent advances in immunotherapy and targeted therapy have dramatically increased patient survival for patients with melanoma. Similar advances in molecular targeted PET imaging can identify molecular pathways that promote disease progression and therefore offer physiological information. Thus, they can be used to assess prognosis, tumor heterogeneity, and identify instances of treatment failure. Numerous agents tested preclinically and clinically demonstrate promising results with high tumor-to-background ratios in both primary and metastatic melanoma tumors. Here, we detail the development and testing of multiple molecular targeted PET-imaging agents, including agents for general oncological imaging and those specifically for PET imaging of melanoma. Of the numerous radiopharmaceuticals evaluated for this purpose, several have made it to clinical trials and showed promising results. Ultimately, these agents may become the standard of care for melanoma imaging if they are able to demonstrate micrometastatic disease and thus provide more accurate information for staging. Furthermore, these agents provide a more accurate way to monitor response to therapy. Patients will be able to receive treatment based on tumor uptake characteristics and may be able to be treated earlier for lesions that with traditional imaging would be subclinical, overall leading to improved outcomes for patients.

Targeting of Ubiquitin E3 Ligase RNF5 as a Novel Therapeutic Strategy in Neuroectodermal Tumors.

Simple SummaryNeuroblastoma and melanoma represent two common aggressive tumors of infancy and adulthood, respectively, with the same origin and poor prognosis. Despite the aggressive treatment, advanced neuroblastoma and melanoma patients are often refractory to therapy, relapse and die. Thus, novel therapeutic strategies are urgently needed. In this study, we demonstrated that RNF5, a ubiquitin ligase involved in the degradation of misfolded proteins, was expressed in neuroblastoma and melanoma patients and positively correlated with better outcome. In line with this observation, Analog-1, a pharmacological activator of RNF5, exerted a potent cytotoxic effect on in vitro and in vivo neuroblastoma and melanoma models by modulating the metabolism, reducing the growth and inducing the death of tumor cells. This study is of high translational relevance since it validates RNF5 as an innovative drug target and supports the development of novel therapies for neuroblastoma and melanoma patients in order to ameliorate their clinical outcome.RNF5, an endoplasmic reticulum (ER) E3 ubiquitin ligase, participates to the ER-associated protein degradation guaranteeing the protein homeostasis. Depending on tumor model tested, RNF5 exerts pro- or anti-tumor activity. The aim of this study was to elucidate the controversial role of RNF5 in neuroblastoma and melanoma, two neuroectodermal tumors of infancy and adulthood, respectively. RNF5 gene levels are evaluated in publicly available datasets reporting the gene expression profile of melanoma and neuroblastoma primary tumors at diagnosis. The therapeutic effect of Analog-1, an RNF5 pharmacological activator, was investigated on in vitro and in vivo neuroblastoma and melanoma models. In both neuroblastoma and melanoma patients the high expression of RNF5 correlated with a better prognostic outcome. Treatment of neuroblastoma and melanoma cell lines with Analog-1 reduced cell viability by impairing the glutamine availability and energy metabolism through inhibition of F1Fo ATP-synthase activity. This latter event led to a marked increase in oxidative stress, which, in turn, caused cell death. Similarly, neuroblastoma- and melanoma-bearing mice treated with Analog-1 showed a significant delay of tumor growth in comparison to those treated with vehicle only. These findings validate RNF5 as an innovative drug target and support the development of Analog-1 in early phase clinical trials for neuroblastoma and melanoma patients.

Development of a TCR-like antibody and chimeric antigen receptor against NY-ESO-1/HLA-A2 for cancer immunotherapy

BackgroundThe current therapeutic antibodies and chimeric antigen receptor (CAR) T cells are capable of recognizing surface antigens, but not of intracellular proteins, thus limiting the target coverage for drug development....

Prognostic biomarkers of cutaneous melanoma.

Melanomas account for only approximately 4% of diagnosed skin cancers in the United States but are responsible for the majority of deaths caused by skin cancer. Both genetic factors and ultraviolet (UV) radiation exposure play a role in the development of melanoma. Although melanomas have a strong propensity to metastasize when diagnosed late, melanomas that are diagnosed and treated early pose a low mortality risk. In particular, the identification of patients with increased metastatic risk, who may benefit from early adjuvant therapies, is crucial, especially given the advent of new melanoma treatments. However, the accuracy of classic clinical and histological variables, including the Breslow thickness, presence of ulceration, and lymph node status, might not be sufficient to identify such individuals. Thus, there is a need for the development of additional prognostic melanoma biomarkers that can improve early attempts to stratify melanoma patients and reliably identify high-risk subgroups with the aim of providing effective personalized therapies. In our current work, we discuss and assess emerging primary melanoma tumor biomarkers and prognostic circulating biomarkers. Several promising biomarkers show prognostic value (eg, exosomal MIA (ie, melanoma inhibitory activity), serum S100B, AMLo signatures, and mRNA signatures); however, the scarcity of reliable data precludes the use of these biomarkers in current clinical applications. Further research is needed on several promising biomarkers for melanoma. Large-scale studies are warranted to facilitate the clinical translation of prognostic biomarker applications for melanoma in personalized medicine.

Prognostic Utility of CpG Island Hypermethylated Phenotype in Early-Stage Invasive Primary Melanomas

In their article in the Journal of Investigative Dermatology, Conway etal. (2021) show the significance of the CpG island methylator phenotype (CIMP) subclass in early-stage invasive primary melanomas, particularly in the lentigo maligna melanoma histological subtype. CIMP melanomas had reduced melanoma-specific survival compared with intermediate and low methylation subtypes. This study emphasizes the importance of epigenomic changes in early-stage primary tumors that are associated with poor prognosis.