Immunotherapy Of Melanoma Research Articles

Quantifying in vivo collagen reorganization during immunotherapy in murine melanoma with second harmonic generation imaging

Quantifying in vivo collagen reorganization during immunotherapy in murine melanoma with second harmonic generation imaging

Estimating scenarios for survival time in patients with advanced melanoma receiving immunotherapy and targeted therapy.

We aim to provide survival scenario estimates for patients with advanced melanoma starting targeted therapies and immunotherapies. We sought randomized trials of targeted therapies and immunotherapies for advanced melanoma and recorded the following percentiles (represented survival scenario) from each overall survival (OS) curve: 90th (worst-case), 75th (lower-typical), 50th (median), 25th (upper-typical), and 10th (best-case). We tested whether these scenarios can be estimated for each OS curve by multiplying its median by 4 multiples: 0.25 (worst-case), 0.5 (lower-typical), 2 (upper-typical), and 3 (best-case). We identified 15 trials with 8025 patients. For first-line combination targeted therapy treatment groups, the median (interquartile range, IQR) in months for each percentile was: 90th, 6.2 (6.0-6.5); 75th, 11.3 (11.3-11.4); and median, 24.4 (23.5-25.3). For the first-line combination immunotherapy treatment group, the percentiles in months were: 90th, 3.9 (2.8-4.5); 75th, 13.4 (10.1-15.4), median 73 (not applicable). In targeted therapy groups, simple multiples of the median OS were accurate for estimating the 90th percentile in 80%; 75th percentile in 40%; 25th percentile in 100%. In immunotherapy groups, these multiples were accurate at 0% for the 90th percentile, and 43% for the 75th percentile. The 90th percentile (worst-case scenario) was better estimated as 1/6× median OS, and the 75th percentile (lower-typical) as 1/3× median OS. Simple multiples of the median OS are a useful framework to estimate scenarios for survival for patients receiving targeted therapies, not immunotherapy. Longer follow-up is required to estimate upper-typical and best-case scenarios.

Quantifying in vivo collagen reorganization during immunotherapy in murine melanoma with second harmonic generation imaging.

Increased collagen linearization and deposition during tumorigenesis can impede immune cell infiltration and lead to tumor metastasis. Although melanoma is well studied in immunotherapy research, studies that quantify collagen changes during melanoma progression and treatment are lacking. We aim to image in vivo collagen in preclinical melanoma models during immunotherapy and quantify the collagen phenotype in treated and control mice. Second-harmonic generation imaging of collagen was performed in mouse melanoma tumors in vivo over a treatment time course. Animals were treated with a curative radiation and immunotherapy combination. Collagen morphology was quantified over time at an image and single-fiber level using CurveAlign and CT-FIRE software. In immunotherapy-treated mice, collagen was reorganized toward a healthy phenotype, including shorter, wider, curlier collagen fibers, with modestly higher collagen density. Temporally, collagen fiber straightness and length changed late in treatment (days 9 and 12), while width and density changed early (day 6) compared with control mice. Single-fiber collagen features calculated in CT-FIRE were the most sensitive to the changes among treatment groups compared with bulk collagen features. Quantitative second-harmonic generation imaging can provide insight into collagen dynamics in vivo during immunotherapy, with key implications in improving immunotherapy response in melanoma and other cancers.

Preoperative-postoperative immunotherapy as treatment of borderline resectable and oligoprogressive stage III B-D and IV melanoma

IntroductionPerioperative therapy has gained significant importance in patients with advanced melanoma. Currently, there is little data on the routine use of preoperative immunotherapy in metastatic melanoma outside clinical trials. This study aimed to evaluate the effectiveness of preoperative treatment in patients with borderline resectable stage III or IV melanoma as well as in oligoprogressing stage IV cases; the secondary aim is to describe the safety of surgery after immunotherapy. Materials and methodsSince 1/Jan/2016 seventeen patients were treated with curative intent neoadjuvant immunotherapy, surgery, and adjuvant immunotherapy, while nineteen patients were operated due to oligoprogression while treted with immunotherapy. Survival was analyzed using the Kaplan-Meier method and association between variables was tested using the chi-squared test. ResultsR0 resection was achieved in 76.5 % of cases after neoadjuvant immunotherapy. 24 % of patients achieved objective RECIST response and 35 % complete or major pathological response. At the median follow-up time of 51.4 months, 64.7 % of patients were free of PD after perioperative treatment, while 3-year RFS and OS rates were 68 % and 80.9 %, respectively. R0 resection was achieved in 73.7 % of oligo-progressing nodules. The median time to PD on immunotherapy after the first oligoprogression was 10.3 months. Immunotherapy did not result in any unexpected surgical complications. No patient died during preoperative treatment due to immunotherapy toxicity or disease progression. ConclusionsWe confirmed treatment safety and long-term disease control after perioperative immunotherapy. Patients with borderline resectable melanoma should be referred to reference centers using neoadjuvant immunotherapy.

Current knowledge about immunotherapy resistance for melanoma and potential predictive and prognostic biomarkers.

Melanoma still reaches thousands of new diagnoses per year, and its aggressiveness makes recovery challenging, especially for those with stage III/IV unresectable melanoma. Immunotherapy, emerging as a beacon of hope, stands at the forefront of treatments for advanced melanoma. This review delves into the various immunotherapeutic strategies, prominently featuring cytokine immunotherapy, adoptive cell therapy, immune checkpoint inhibitors, and vaccinations. Among these, immune checkpoint inhibitors, notably anti-programmed cell death-1 (PD-1) and anti-cytotoxic T lymphocyte antigen-4 (CTLA-4) antibodies, emerge as the leading strategy. However, a significant subset of melanoma patients remains unresponsive to these inhibitors, underscoring the need for potent biomarkers. Efficient biomarkers have the potential to revolutionize the therapeutic landscape by facilitating the design of personalized treatments for patients with melanoma. This comprehensive review highlights the latest advancements in melanoma immunotherapy and potential biomarkers at the epicenter of recent research endeavors.

Decoupling the correlation between cytotoxic and exhausted T lymphocyte states enhances melanoma immunotherapy response prediction

Cytotoxic T lymphocyte (CTL) and terminal exhausted T lymphocyte (ETL) activities crucially influence immune checkpoint inhibitor (ICI) response. Despite this, the efficacy of ETL and CTL transcriptomic signatures for response prediction remains limited. Investigating this across the TCGA and publicly available single-cell cohorts, we find a strong positive correlation between ETL and CTL expression signatures in most cancers. We hence posited that their limited predictability arises due to their mutually canceling effects on ICI response. Thus, we developed DETACH, a computational method to identify a gene set whose expression pinpoints to a subset of melanoma patients where the CTL and ETL correlation is low. DETACH enhances CTL's prediction accuracy, outperforming existing signatures. DETACH signature genes activity also demonstrates a positive correlation with lymphocyte infiltration and the prevalence of reactive Tcells in the tumor microenvironment (TME), advancing our understanding of the CTL cell state within the TME.

A Bioactive Injectable Hydrogel Regulates Tumor Metastasis and Wound Healing for Melanoma via NIR-Light Triggered Hyperthermia.

Surgical resection remains the mainstream treatment for malignant melanoma. However, challenges in wound healing and residual tumor metastasis pose significant hurdles, resulting in high recurrence rates in patients. Herein, a bioactive injectable hydrogel (BG-Mngel) formed by crosslinking sodium alginate (SA) with manganese-doped bioactive glass (BG-Mn) is developed as a versatile platform for anti-tumor immunotherapy and postoperative wound healing for melanoma. The incorporation of Mn2+ within bioactive glass (BG) can activate the cGAS-STING immune pathway to elicit robust immune response for cancer immunotherapy. Furthermore, doping Mn2+ in BG endows system with excellent photothermal properties, hence facilitating STING activation and reversing the tumor immune-suppressive microenvironment. BG exhibits favorable angiogenic capacity and tissue regenerative potential, and Mn2+ promotes cell migration in vitro. When combining BG-Mngel with anti-PD-1 antibody (α-PD-1) for the treatment of malignant melanoma, it shows enhanced anti-tumor immune response and long-term immune memory response. Remarkably, BG-Mngel can upregulate the expression of genes related to blood vessel formation and promote skin tissue regeneration when treating full-thickness wounds. Overall, BG-MnGel serves as an effective adjuvant therapy to regulate tumor metastasis and wound healing for malignant melanoma.

Understanding the Association Between Social Determinants of Health and Receipt of Immunotherapy for Melanoma.

In this review article, we sought to elucidate how the social determinants of health, including socioeconomic status, education, neighborhood or physical environment, access to healthcare, and race/ethnicity, affect the likelihood of receiving immunotherapy, a novel and expensive treatment for melanoma.  Methods: The PubMed database was queried up to May 2023, for studies pertaining to health disparities in melanoma, including studies examining the utilization of immunotherapy agents for the treatment of melanoma across various social determinants of health. Disparities in the utilization of immunotherapy exist across various social determinants. A total of 10 studies were found to report on disparities in receipt of immunotherapy. These studies reported an association between insurance status, education level, socioeconomic status, as well as proximity to a cancer research center, and a lower likelihood of receiving immunotherapy. As the number of novel immunotherapy drugs grows, it is important to understand the various disparities affecting the delivery of immunotherapy across social determinants. The findings from this study can help to drive public health policy aimed at addressing inequities in the treatment of melanoma as well as other cancers.    J Drugs Dermatol. 2024;23(5):311-315. doi:10.36849/JDD.7803.

Single cell analysis of melanoma reveals a prognostic myeloid cell signature associated with survival and response to immunotherapy in advanced melanoma

Abstract INTRODUCTION: We sought to elucidate myeloid sub-type differences to characterize biology and support therapeutic strategies in melanoma patients with diverse biogeophaphies. METHODS: scRNA-seq of melanoma were combined from 6 datasets with 126 patients. After integration, cells were clustered with scCCESS, using an artificial neural network. We conducted Recursive Partitioning Analysis (RPA), differential expressed gene (DEG) analysis, and pseudobulk comparison. We validated the signature using MuSiC deconvolution on bulk RNA data. RESULTS: 102,971 single cells from 126 patients generated myeloid cells of 6 cell types. RPA analysis of 42 patients with melanoma brain metastases revealed a single myeloid population associated with median survival months (13 vs 32 vs 52, p=0.029). Partial Response (p=0.010) and adjuvant targeted therapy (p=0.036) differed. Myeloid cell type 1 was enriched with CLEC10A, AXL, and MHC Class II genes. 42 patients on nivolumab were used to validate signature with on treatment biopsy with improved median survival months (13.25 vs 30, p=0.046) and Partial Response (p<0.001). 19 patients shifted high infiltration groups during treatment with 11% dropping, 44% increasing, and 47% remaining high. CONCLUSIONS: Increased infiltration of myeloid cells showed improved survival and treatment response in melanoma brain metastases. Validation of the signature showed an association with nivolumab response and survival.

Increasing melanoma incidence with unchanged mortality: more sunshine, better treatment, increased diagnostic activity, overdiagnosis or lowered diagnostic threshold?

Increasing melanoma incidence with less increasing mortality is observed in several countries. This discrepancy is not well understood. In this study, our aim was to discuss factors [ultraviolet radiation (UVR) exposure, melanoma treatment, diagnostic activity, overdiagnosis, pathologists' diagnostic threshold and clinicians' propensity to remove suspect skin lesions] that might influence melanoma incidence and mortality in Denmark. This was a register study with the number of melanocyte-related lesions and melanoma mortality based on comprehensive national pathology and mortality databases for the period 1999-2019. We investigated melanocyte-related diagnoses and mortality in a population of 5.5 million with a national healthcare system. Age-adjusted melanoma mortality and age-adjusted incidence of benign naevi, atypical lesion, or melanoma in situ and of invasive melanoma were computed for data analysis. In total, 1 434 798 biopsies were taken from 704 682 individuals (65% female). The mean age at biopsy was 39.8 years in males and 37.6 in females. In males and females, the incidence of invasive melanoma increased by 87% during the period 1999-2011. During the subsequent period it increased by 9% in males but remained unchanged in females. The incidence of melanoma in situ increased by 476% in males and 357% in females during the study period, while the increases for atypical melanocytic lesions were 1928% and 1686%, respectively. Biopsy rates increased by 153% in males and 118% in females from 1999 through 2011 but fell by 20% in males and 22% in females during the subsequent period. Mortality varied slightly from year to year without any significant time trend for males or females. We identified no evidence of increased UVR exposure over the latest 30 years in Denmark. Immunotherapy of advanced melanoma was introduced in Denmark in 2010 and came into general use in 2014. Comprehensive national data demonstrate increasing melanoma incidence correlated with increasing biopsy rates, but with no change in mortality. Previously suggested explanations for such a trend are a lowered threshold of melanoma diagnosis among pathologists, increased diagnostic activity in the presence of overdiagnosis and improved melanoma treatment. Because the study is observational and we have more explanatory factors than outcomes, the findings do not warrant conclusions about causal relationships.

Exploring a specialized programmed-cell death patterns to predict the prognosis and sensitivity of immunotherapy in cutaneous melanoma via machine learning.

The mortality and therapeutic failure in cutaneous melanoma (CM) are mainly caused by wide metastasis and chemotherapy resistance. Meanwhile, immunotherapy is considered a crucial therapy strategy for CM patients. However, the efficiency of currently available methods and biomarkers in predicting the response of immunotherapy and prognosis of CM is limited. Programmed cell death (PCD) plays a significant role in the occurrence, development, and therapy of various malignant tumors. In this research, we integrated fourteen types of PCD, multi-omics data from TCGA-SKCM and other cohorts in GEO, and clinical CM patients to develop our analysis. Based on significant PCD patterns, two PCD-related CM clusters with different prognosis, tumor microenvironment (TME), and response to immunotherapy were identified. Subsequently, seven PCD-related features, especially CD28, CYP1B1, JAK3, LAMP3, SFN, STAT4, and TRAF1, were utilized to establish the prognostic signature, namely cell death index (CDI). CDI accurately predicted the response to immunotherapy in both CM and other cancers. A nomogram with potential superior predictive ability was constructed, and potential drugs targeting CM patients with specific CDI have also been identified. Given all the above, a novel CDI gene signature was indicated to predict the prognosis and exploit precision therapeutic strategies of CM patients, providing unique opportunities for clinical intelligence and new management methods for the therapy of CM.

Transcriptomics analysis of LINC02202/XBP1 axis in melanoma: Implications for drug targeting and PD-1 monoclonal antibody efficacy.

Malignant melanoma (MM) is a highly aggressive and deadly form of skin cancer, primarily caused by recurrence and metastasis. Therefore, it is crucial to investigate the regulatory mechanisms underlying melanoma recurrence and metastasis. Our study has identified a potential targeted regulatory relationship between LINC02202, miR-526b-3p and XBP1 in malignant melanoma. Through the regulation of the miR-526b-3p/XBP1 signalling pathway, LINC02202 may play a role in tumour progression and immune infiltration and inhibiting the expression of LINC02202 can increase the efficacy of immunotherapy for melanoma. Our findings shed light on the impact of LINC02202/XBP1 on the phenotype and function of malignant melanoma cells. Furthermore, this study provides a theoretical foundation for the development of novel immunotherapy strategies for malignant melanoma.

Abstract 6691: Engraftment as a determinant of response in fecal microbiome transplantation interventions for immunotherapy in melanoma

Abstract Background: Distinct gut microbiome signatures are associated with response, resistance, and toxicity to immune checkpoint blockade (ICB). Fecal microbiome transplants (FMT) have validated the importance of the gut microbiome in enhancing response and overcoming resistance to immunotherapy. However, donor selection remains a key challenge for FMT. Heterogenous responses using Healthy Donors (HD) and ICB Complete Responders (CR) as FMT donors suggest donor characteristics alone do not determine response. Here, we posit that donor-recipient relationships are critical in determining clinical responses to FMT. Methods: We studied a cohort of ICB-refractory, metastatic melanoma patients treated with combined FMT and ICB (10 recipients, 2 donors). Patient gut microbiomes were profiled using whole metagenomic sequencing (WMS) of longitudinal stool collections (baseline, day 7, day 31, and day 65 post-FMT). Immune infiltration of on-treatment tumor and colon biopsies was quantified with immunohistochemistry. mTraCX, an Earth Mover’s Distance-based algorithm, was used to evaluate taxonomic engraftment between donors and recipients. Bray-Curtis distance was used to measure functional similarities between donor and recipient gut microbiome. Clinical findings were validated in pre-clinical FMT experiments performed on BrafV600EPten−/− melanoma-bearing mice. Results: One-third of recipients (3/10) developed an objective response (R) to ICB following FMT. mTraCX demonstrated an association between clinical response to FMT and durable engraftment of donor microbiota at day 65 post-FMT (p=0.025). Taxonomic engraftment (mTraCX) correlated positively with functional engraftment (Bray-Curtis distance) (r=0.89, p<0.0001). Enhanced engraftment was associated with increased CD4 (r = -0.87, p=0.0045) and CD8 (r = -0.6, p=0.09) T-cell infiltration in the colon, and a trend towards increased CD8 T-cell infiltration (r = -0.5, p=0.2) in the tumor following treatment with FMT+ICB. Pre-clinical models paralleled our clinical findings as responding mice showed better donor engraftment than non-responding mice (p<0.0001 on day 4 and day 24 following FMT). Conclusions: Our data shows that donor engraftment is a favorable prognostic factor for ICB treatments combined with FMT. Future investigations will aim to develop donor-recipient matching criteria to enhance the feasibility and integration of FMTs into clinical practice. Citation Format: Manoj Chelvanambi, Ashish V. Damania, Sarah B. Johnson, Golnaz Morad, Rossana N. Lazcano, Beth A. Helmink, Lon W. Fong, Khalida Wani, Y David Seo, Elizabeth M. Park, Reed I. Ayabe, Bhavana Singh, Matthew C. Wong, Davis R. Ingram, Michael G. White, Alexander J. Lazar, Aditya K. Mishra, Nadim J. Ajami, Erez N. Baruch, Jennifer A. Wargo. Engraftment as a determinant of response in fecal microbiome transplantation interventions for immunotherapy in melanoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6691.

Abstract 2801: Identifying gut microbial determinants of clonal hematopoiesis of indeterminate potential (CHIP) in immunotherapy treated melanoma patients

Abstract INTRO: Clonal hematopoiesis (CH) of indeterminate potential (CHIP) is associated with poor outcomes in those with non-hematologic cancers. CH mutated macrophages and neutrophils have increased capacity to home to peripheral tissues, driving local inflammation; they are also implicated in immunotherapy related toxicity. The relationship between CH and the microbiome in those treated with immunotherapy is not well understood. RESULTS: 35 patients with stage IV melanoma treated with upfront immunotherapy; treatment and cohort characteristics are below (Table 1). We performed error corrected duplex sequencing on peripheral blood mononuclear cells using a panel previously validated for CH mutations. With a cutoff of 0.5% variant allele frequency (VAF), among 10 CHIP positive patients, we found mutations in TET2 (8/10), DNMT3A (7/10), PPM1D (2/10), and JAK2 (1/10). There was no difference in either survival or response based on CHIP status (Log-Rank Chi-Square p=0.44); however, CHIP positivity was associated with greater microbiome richness as measured by alpha diversity (p=0.0012 Shannon diversity) and distinct structural/compositional diversity vs CHIP negative patients as measured by beta diversity (p=0.032, R Squared= 0.045). We inferred KEGG pathway activity from whole genome sequencing and identified that CHIP positive patients were enriched for exopolysaccharide biosynthesis while CHIP negative patients had higher expression of nucleotide sugars biosynthesis and amino acid metabolism pathways. DISCUSSION: In patients treated with immunotherapy for melanoma, microbiome diversity signatures correlate with presence of CHIP. The analysis suggests that there are distinct taxonomic and functional features defining CHIP positivity. The effect of these cells in the tumor microenvironment and their role in immunotherapy response requires further exploration. Citation Format: Eleanor A. Fallon, Samuel Urrutia, Reed Ayabe, Manoj Chelvanambi, Ashish Damania, Sarah Johnson, Tomoyuki Tanaka, Zongrui Li, Yongwoo David Seo, Samuel Cass, Matthew C. Wong, Nadim Ajami, Jennifer Wargo, Koichi Takahashi. Identifying gut microbial determinants of clonal hematopoiesis of indeterminate potential (CHIP) in immunotherapy treated melanoma patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2801.

Abstract 2902: CA-4948 (emavusertib) improves treatment response of preclinical metastatic brain melanoma to anti-PD-1 immune checkpoint blockade

Abstract Background: Although recent advances in immunotherapy for metastatic melanoma have transformed the treatment paradigm for a disease that once carried a grim prognosis, nearly 50% of patients fail to reach a complete response to immune checkpoint blockade (ICB) due to multiple mechanisms of tumor-induced immune resistance. These challenges are amplified in the CNS tumor microenvironment (TME) where metastatic brain melanoma (MBM) demonstrates diminished clinical benefit to ICB treatment. A deeper understanding of these mechanisms are required to improve therapeutic response to ICB for these patients. Our group has previously identified that aberrant activation of the myddosomal cascade through downstream interleukin (IL)-1 receptor-associated kinase (IRAK-4) signaling results in chronic stimulation of MAPK and NF-κB in MBM. Further investigation reveals myddosome signaling emanates in large part from the TME, resulting in reflexive immune suppression. CA-4948 (emavusertib), a small molecule inhibitor of IRAK-4, is capable of reaching therapeutic dose levels in the brain where it demonstrates on-target inhibition of this pathway. These data highlight a unique therapeutic opportunity where selective inhibition of immune-suppressive signaling via targeted IRAK-4 blockade may sensitize MBM to anti-PD-1 ICB. Methods Multispectral imaging of patient MBM samples were analyzed for myddosome expression in the TME. Melanoma preclinical models, including both primary site (cutaneous) and metastatic brain disease, were evaluated for tumor burden and survival in response to CA-4948 treatment alone and in combination with anti-PD-1 ICB. Immunological responses of tumor to treatment were evaluated in two transgenic reporter models, CCR2RFPCX3CR1GFP and IFNγIRES-EYFP, to determine both the distribution and activation of infiltrating immune cells. Tumor-associated myeloid cells were assessed for phenotypic markers by multiparameter flow cytometry. Results Myddosome signaling was found to be elevated in tumor-associated immune cells in patient MBM specimens. Treatment of preclinical melanoma with CA-4948 combined with anti-PD-1 ICB resulted in significantly reduced tumor growth and improved survival in three independent models. CA-4948 treatment was associated with reduced tumor recruitment of peripherally derived tumor-associated macrophages, as well as increased lymphocyte infiltration and improved pro-inflammatory signaling measured by increased IFNγ expression in the combinatorial setting. Conclusion Targeted inhibition of IRAK-4 with CA-4948 improves immune surveillance and activation in preclinical models when combined with anti-PD-1 ICB, resulting in reduced tumor growth and increased survival. Thus, CA-4948 may be an effective adjuvant treatment strategy alongside anti-PD-1 ICB for the treatment of metastatic melanoma. Citation Format: Christina A. von Roemeling, Bently P. Doonan, Amanda M. Acevedo, Jeet A. Patel, Savannah L. Carpenter, Alisha Bhatia, Reinhard W. von Roemeling, Jamison Hoffman, Maureen Lane, Duane A. Mitchell. CA-4948 (emavusertib) improves treatment response of preclinical metastatic brain melanoma to anti-PD-1 immune checkpoint blockade [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2902.

Abstract 4083: Pre-clinical development of IAMA-005, a long-acting cytokine fusion of modified IL-2 and IFN-α

Abstract In 1990s, both IL-2 and IFN-α were approved as the first two immunotherapies for metastatic melanoma and renal cell carcinoma; IFN-α was also approved for hairy cell leukemia. Although the response rates are relatively low, along ~25%, those who responded have long term survival benefits. However, the severe toxicity especially in high dose prohibited their broad use in oncology. Recently, there have been tremendous interests in modifying these two cytokines in the efforts to reduce the toxicity and enhance the activity. One such effort is to enhance the binding of IL-2 to the intermediate affinity β/γ receptors, which are expressed and function on CD8 T cells and NK cells. Another effort is to reduce the binding of IL-2 to high affinity α/β/γ receptors which mostly expressed on Treg and stimulate the growth of Treg cells, which suppress immune responses. Recently, whether it’s better to target intermediate affinity or high affinity for cancer therapy has become controversial with some studies showing that high affinity receptor engagements are required for robust anti-tumor activity while others favoring intermediate affinity receptor engagement for better efficacy; However, the clinical comparison is still lacking to be sure which approach is better. Here we have developed a long-acting novel IL-2-Fc-IFN-α fusion molecule termed IAMA-005 that has mutations to reduce the toxicity effects of IL-2 and IFN-α. We have characterized this molecule preclinically both in vitro and in vivo. IAMA-005 has demonstrated a potent tumor cell killing activities in numerous cancer cell lines including BT-474, SK-OV-3, NCI-N87, OE19, HCC-1954, MDA-MB-231, MDA-MB-468. When combined with IAMA-004 (a Her2-CD47-CD16 tri-specific antibody) in vitro, the tumor cell killing activities were dramatically increased. In addition, IAMA-005 was also tested in patient-derived Ex-Vivo fluids (one malignant pleural effusion and one malignant asities) and demonstrated excellent tumor cell killing efficacies. In addition, the killing activities of IAMA-005 could be attributed to the specific part of the fusion molecule because of the TME immune cell compositions. The in vivo assays to demonstrate efficacy and safety are ongoing and will be presented in the poster. These results suggest that this fusion cytokine molecule may be used in monotherapy in certain indications and an excellent complementary therapeutic to antibody targeted therapies or immunotherapies when used in combination. Citation Format: Liming Liu, Zhen Han, Yang Fan, Qi Pan. Pre-clinical development of IAMA-005, a long-acting cytokine fusion of modified IL-2 and IFN-α [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4083.

Abstract 7518: Neoadjuvant-adjuvant pembrolizumab in resectable advanced basal cell carcinoma of the head and neck: An open-label, single-arm, phase 1b trial

Abstract Introduction: BCC is a common form of skin cancer that shares treatment-related aspects with the more well-studied skin malignancy, melanoma, including sensitivity to anti-PD-1/PD-L1 immunotherapy. However, despite major advances in peri-operative immunotherapy for melanoma, little is known regarding these strategies in BCC. This phase 1B, single-arm study evaluated neoadjuvant-adjuvant treatment with pembrolizumab (PEMBRO) together with standard of care (SOC) resection in advanced BCC of the head and neck. Methods: Eligible patients had resectable, locally advanced BCC of the head and neck, defined by at least one of the following high-risk characteristics: a measurement of ≥ 20 mm, indication for post-operative radiation, or perineural invasion (PNI) in multiple nerves. Patients were naive to hedgehog inhibitors (HHI) and had an ECOG of 0 or 1. All patients received IV PEMBRO at a dose of 200 mg every 3 weeks for a total of 4 cycles, then within 4 weeks underwent a SOC resection followed by adjuvant PEMBRO until a total of 17 cycles was completed. After the 30-day post treatment safety follow-up visit, patients were followed for up to 5 years post-operatively. The primary endpoint was pathological response rate. Secondary endpoints included RECIST response by radiographic or physical exam, adverse events (AE), and recurrence-free survival (RFS). Results: 13 patients were enrolled in the trial from July 2020 to May 2023, and received at least one dose of PEMBRO. Two patients withdrew from the trial after one dose of PEMBRO, one following treatment-related G3 hepatitis and a second due to an unrelated medical complication (cholecystitis). Out of 11 patients undergoing surgical resection, 10 patients received 4 out of 4 and 1 patient received 3 out of 4 planned cycles of neoadjuvant PEMBRO (investigator preference without new related AE). Pathological complete response (pCR) was observed in 3 patients (23%). For those with RECIST measurable disease, 2 patients demonstrated a complete response (CR), 1 patient a partial response (PR), and 5 patients showed stable disease (SD). Two patients had progressive disease (PD). One patient with a complete pathologic response had a discordant RECIST response with PD noted radiographically. All 13 patients experienced at least one AE of G1 or 2. The highest grade of related AEs were noted in 2 patients with grade 3 hepatitis and pruritus respectively that resolved with supportive therapy. As of November 2023, the median follow-up time is 17.6 months with no recurrences noted. Conclusions: Neoadjuvant-adjuvant PEMBRO shows promising efficacy and an acceptable safety profile in resectable advanced BCC of the head and neck. Given these positive results and the healthcare burden BCC accounts for, these findings warrant further study. Citation Format: Grace M. Jones, James Isaacs, Lucy Boyce Kennedy, Jennifer Ko, Allison Vidimos, Alok Vij, Christine Poblete-Lopez, Jennifer Lucas, Yee Peng Phoon, Melissa McEnery-Stonelake, Jon Meine, Thach-Giao Truong, Pauline Funchain, Brian Gastman. Neoadjuvant-adjuvant pembrolizumab in resectable advanced basal cell carcinoma of the head and neck: An open-label, single-arm, phase 1b trial [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7518.

Abstract 5081: Immune sensitization of melanoma to checkpoint inhibitor therapy using acoustically active nanoparticles

Abstract Advanced melanoma remains the most fatal form of skin cancer with novel therapeutic approaches required to treat inoperable metastatic lesions. While immunotherapies have shown promise in improving long-term melanoma survival, its treatment efficacy is limited, with only 50% of patients responding. Focused ultrasound (FUS) offers as a non-invasive strategy for targeted tumor ablation, thereby strengthening immunotherapy efficacy by release of tumor associated materials. However, control over tumor material release through FUS, without causing excessive thermal damage to surrounding healthy tissue remains challenging. To address this challenge, our group has previously developed acoustically active nanoparticles (AANPs) responsive to low intensity ultrasound for mechanical tumor ablation by generating strong and durable acoustic cavitation in the tumor tissue. Building upon previous success with AANPs, our current work focuses on sensitizing melanoma tumors to checkpoint inhibitor therapy by releasing tumor antigens into circulation using AANPs and FUS. Our findings revealed sensitization of an immunologically cold B16-F10 metastatic melanoma tumors following treatment, which resulted in a notable 12-day stall in tumor growth. When combined with immune checkpoint inhibitors α-PD-L1 and α-CTLA-4, this approach showed a complete response in B16-F10 bearing mice with impressive memory immune response upon a tumor rechallenge. Herein, these novel AANPs represent a promising advancement to enable accurate immune surveillance by boosting the release of tumor antigens and offers new strategies for improved immunotherapy of melanoma and other solid tumors. Citation Format: Michael Ian Henderson, Li Xiang, Samuel Drennan, Xin Yi, Jared Fischer, Adem Yildirim. Immune sensitization of melanoma to checkpoint inhibitor therapy using acoustically active nanoparticles [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5081.

Stigmasterol Exerts an Anti-Melanoma Property through Down-Regulation of Reactive Oxygen Species and Programmed Cell Death Ligand 1 in Melanoma Cells.

Cancer immunotherapy as a promising anti-cancer strategy has been widely studied in recent years. Stigmasterol (STIG), a phytosterol, is known to have various pharmacological effects, including anti-inflammatory effects. However, the pharmacological role of STIG on melanoma immunotherapy has not been investigated. The present study demonstrates the anti-melanoma potency of STIG through the regulation of PD-L1 levels. The results reveal that STIG reduces reactive oxygen species (ROS) levels induced by hydrogen peroxide and increases glutathione levels decreased by α-MSH in B16F10 cells. Moreover, STIG significantly decreases melanin content and tyrosinase activities elevated by α-MSH. It also suppresses nitric oxide production induced by α-MSH. Additionally, STIG induces apoptosis with the up-regulation of PARP activation. STIG inhibits IFN-γ-induced PD-L1 expression and STAT1 phosphorylation levels. STIG also reverses the up-regulation of PD-L1 and phosphorylated STAT1 levels augmented by cisplatin, and STIG enhances CD8(+) T-cell-mediated cell death against B16F10 cells. These findings represent the first evidence of pro-apoptotic activity of STIG on melanoma cells through the down-regulation of ROS and PD-L1 pathways. Therefore, STIG may be an effective candidate for melanoma immunotherapy.

Fine tuning of CpG spatial distribution with DNA origami for improved cancer vaccination.

Multivalent presentation of ligands often enhances receptor activation and downstream signalling. DNA origami offers a precise nanoscale spacing of ligands, a potentially useful feature for therapeutic nanoparticles. Here we use a square-block DNA origami platform to explore the importance of the spacing of CpG oligonucleotides. CpG engages Toll-like receptors and therefore acts to activate dendritic cells. Through in vitro cell culture studies and in vivo tumour treatment models, we demonstrate that square blocks induce Th1 immune polarization when CpG is spaced at 3.5 nm. We observe that this DNA origami vaccine enhances DC activation, antigen cross-presentation, CD8 T-cell activation, Th1-polarized CD4 activation and natural-killer-cell activation. The vaccine also effectively synergizes with anti-PD-L1 for improved cancer immunotherapy in melanoma and lymphoma models and induces long-term T-cell memory. Our results suggest that DNA origami may serve as a platform for controlling adjuvant spacing and co-delivering antigens in vaccines.