Immune Checkpoint Research Articles

Unleashing the potential of eHealth in outpatient cancer care for patients undergoing immunotherapy-a quantitative study considering patients' needs and current healthcare challenges.

The use of online information and communication is globally increasing in the healthcare sector. In addition to known benefits in other medical fields, possible specific potentials of eHealth lie in the monitoring of oncological patients undergoing outpatient therapy. Specifically, the treatment with immune checkpoint inhibitors (ICI) requires intensive monitoring due to various possible negative side effects. The present study explores cancer patients' perspectives on eHealth and demonstrates how eHealth applications, from the patients' point of view, can contribute to further improving outpatient immunotherapy. Our multicenter study was executed at the university hospitals in Bonn and Aachen. A structured questionnaire was distributed to patients receiving outpatient immunotherapy. Contents addressed were (1) the patients' attitude towards eHealth applications, (2) the use of modern information and communications technologies (ICT) in (2a) everyday life and (2b) health-related information search including eHealth literacy, (3) the use of internet-enabled devices as well as (4) socio-demographic data. 164 patients were included in the study, of whom 39.0% were female and 61.0% male and the average age was 62.8 years. Overall, there was a high distribution of internet-enabled devices for everyday use and a great interest in integrating eHealth applications into outpatient immunotherapy. The assessment of eHealth potentials significantly depended on age. The younger participants demonstrated a broader use of modern ICT and a higher affinity for its use in outpatient immunotherapy. In some aspects, level of education and gender were also relevant factors influencing the patients' view on eHealth. This study demonstrates the potential for further integration of eHealth applications into outpatient immunotherapy from the patients' perspective. It indicates a dependency on age and educational level for the further integration of eHealth into patient care in oncology. Due to particular patient needs regarding age, level of education, gender and other subgroups, specific education and training as well as target-group specific digital health interventions are necessary to fully utilize the potentials of eHealth for outpatient immunotherapy. Future studies are required to specifically address target-group specific usability of eHealth applications and eHealth literacy, as well as to address information security and data protection.

Impact of the Immune Landscape in Follicular Lymphoma: Insights into Histological Transformation in the Rituximab Era.

Background: Follicular lymphoma (FL) presents significant clinical heterogeneity, with some patients experiencing transformation into an aggressive disease, a key contributor to FL-related mortality. Based on gene expression profiles, this study aimed to provide insights into immunological differences associated with transformation. Methods: Gene expression analysis using the NanoString nCounter Tumor Signaling 360 Panel was performed on diagnostic lymphoma samples from 70 FL patients diagnosed in the rituximab era, either non-transforming FL (nt-FL, n = 34) or subsequently transforming FL (st-FL, n = 36), with paired high-grade transformed FL (tFL, n = 36) samples available. In silico immunophenotyping was performed to infer immune cell infiltration using the CIBERSORTx algorithm. Results: The gene expression analysis revealed 164 significantly differentially expressed genes, distinguishing st-FL from nt-FL and generally presenting an upregulation of B cell-related genes (CD40, IRF4, RELB), immunosuppressive molecules (IL10, SOCS3), and immune checkpoint molecules (CD276, TIM3). Analysis of immune cell proportions indicated significant differences in infiltrates of M1-like macrophages (p = 0.007) and neutrophils (p = 0.012) in nt-FL versus st-FL samples. Transformation-free survival (TFS) was associated with high numbers of both these cellular subsets (p = 0.006 and 0 = 0.002, respectively). This was even more evident when combined with inferior TFS in lymphomas with high infiltrates of both cell types (p < 0.001). After transformation, tFL samples showed a reduction in T follicular helper cells (p = 0.008) and an increase in immunosuppressive M2-like macrophages and neutrophils (p < 0.001 and p = 0.028, respectively). Conclusion: By elucidating the distinct molecular and immune landscapes of FL at the time of diagnosis and transformation, this study underscores the importance of immune microenvironment in FL transformation and patient outcome.

Editorial comment on the Role of cytoreductive nephrectomy in the era of immune checkpoint inhibitors: A review of current evidence and ongoing trials.

Editorial comment on the Role of cytoreductive nephrectomy in the era of immune checkpoint inhibitors: A review of current evidence and ongoing trials.

Evaluating the Effectiveness of Nivolumab in Metastatic Lung Cancer Among Patients Aged 65 and Older.

Background: Lung cancer remains the leading cause of cancer-related mortality globally, predominantly affecting older individuals. Despite the increasing use of immune checkpoint inhibitors (ICIs) like nivolumab in non-small cell lung cancer (NSCLC), the efficacy and safety in elderly patients, particularly those aged 65 and above, remain underexplored due to their underrepresentation in clinical trials. Methods: This retrospective study analyzed data from 60 elderly patients (≥65 years) with metastatic NSCLC who received nivolumab as second-line or later therapy between January 2020 and May 2023. Results: The median age was 67 years, with a predominance of males (78%). Nivolumab was administered for a median of 8 cycles, with 33.3% of patients receiving 15 or more cycles. The median OS was 23 months, and the 1-, 3-, and 5-year survival rates were 93.3, 54.1, and 18.6%, respectively. Multivariate analysis identified adenocarcinoma histology, fewer than 15 cycles of nivolumab, and non-response to prior therapies as independent predictors of poor OS. Nivolumab treatment was generally well-tolerated, with 45% of patients experiencing at least grade 1 toxicity. Conclusions: Nivolumab is effective and well-tolerated in elderly patients with metastatic NSCLC, providing survival benefits comparable to those observed in younger populations. The number of treatment cycles and initial response to therapy are key determinants of survival, underscoring the importance of continued treatment in this age group.

Tumor Immune Microenvironment in Intrahepatic Cholangiocarcinoma: Regulatory Mechanisms, Functions, and Therapeutic Implications.

Treatment options for intrahepatic cholangiocarcinoma (iCCA), a highly malignant tumor with poor prognosis, are limited. Recent developments in immunotherapy and immune checkpoint inhibitors (ICIs) have offered new hope for treating iCCA. However, several issues remain, including the identification of reliable biomarkers of response to ICIs and immune-based combinations. Tumor immune microenvironment (TIME) of these hepatobiliary tumors has been evaluated and is under assessment in this setting in order to boost the efficacy of ICIs and to convert these immunologically "cold" tumors to "hot" tumors. Herein, the review TIME of ICCA and its critical function in immunotherapy. Moreover, this paper also discusses potential avenues for future research, including novel targets for immunotherapy and emerging treatment plans aimed to increase the effectiveness of immunotherapy and survival rates for iCCA patients.

PD-L1 protein expression in breast cancer

AimsThe immune checkpoint marker, Programmed cell death-ligand 1 (PD-L1), is expressed by both cancer epithelial cells and tumour-infiltrating immune cells (TICs) thus constituting a potential target for immunotherapy. This is...

Is modulation of immune checkpoints on glioblastoma-infiltrating myeloid cells a viable therapeutic strategy?

The field of immunology has traditionally focused on immune checkpoint modulation of adaptive immune cells. However, many malignancies such as glioblastoma are mostly devoid of T cells and rather are enriched with immunosuppressive myeloid cells of the innate immune system. While some immune checkpoint targets are shared between adaptive and innate immunity, myeloid-specific checkpoints could also serve as potential therapeutics. To better understand the impact of immune checkpoint blockade on myeloid cells, we systematically summarize the current literature focusing on the direct immunological effects of PD-L1/PD-1, CD24/Siglec-10, collagen/LAIR-1, CX3CL1/CX3CR1, and CXCL10/CXCR3. By synthesizing the molecular mechanisms and the translational implications, we aim to prioritize agents in this category of therapeutics for glioblastoma.

Evaluation of a risk-sharing agreement for atezolizumab treatment in patients with non-small cell lung cancer: a strategy to improve access in low-income countries.

Using immune checkpoint inhibitors (IO) is a promising approach to maximize clinical benefits for patients with non-small cell lung cancer (NSCLC). PD-L1 expression serves as a predictive factor for treatment outcomes with IO. However, the high cost of this treatment creates significant barriers to access. Substantial evidence demonstrates the sustained clinical benefits experienced by patients who respond to immunotherapy. While IOs show promise in NSCLC treatment, their high cost poses access barriers. This study focused on a prospective cost analysis conducted at a high-specialty health facility to assess the economic implications of implementing a risk-sharing agreement (RSA) for atezolizumab in NSCLC. The study included 30 patients with advanced NSCLC, with the pharmaceutical company funding the initial cycles. If patients responded, a government program covered costs until disease progression. A median progression-free survival of 4.67 months across populations, rising to 9.4 months for responders. The 2-year overall survival rate for the response group was 64%, significantly higher than for non-response. Without an RSA, a total treatment cost of $881 859.36 ($29 395.31/patient) was reported, compared to $530 467.12 ($17 682.24/patient) with an RSA, representing a 40% cost reduction. In responders, the average cost per year of life per patient dropped by 22%. Risk-sharing, assessed through non-parametric tests, showed a statistically significant difference in pharmacological costs (P < .001). Implementing RSAs can optimize resource allocation, making IO treatment more accessible, especially in low-income countries.

Spatial dynamics of CD39+CD8+ exhausted T cell reveal tertiary lymphoid structures-mediated response to PD-1 blockade in esophageal cancer

Despite the success of immune checkpoint blockade (ICB) therapy for esophageal squamous cell cancer, the key immune cell populations that affect ICB efficacy remain unclear. Here, imaging mass cytometry of tumor tissues from ICB-treated patients identifies a distinct cell population of CD39+PD-1+CD8+ T cells, specifically the TCF1+ subset, precursor exhausted T (CD39+ Tpex) cells, which positively correlate with ICB benefit. CD39+ Tpex cells are predominantly in the stroma, while differentiated CD39+ exhausted T cells are abundantly and proximally within the parenchyma. Notably, CD39+ Tpex cells are concentrated within and around tertiary lymphoid structure (TLS). Accordingly, tumors harboring TLSs have more of these cells in tumor areas than tumors lacking TLSs, suggesting Tpex cell recruitment from TLSs to tumors. In addition, circulating CD39+ Tpex cells are also increased in responders following ICB therapy. Our findings show that this unique subpopulation of CD39+PD-1+CD8+ T cells is crucial for ICB benefit, and suggest a key role in TLS-mediated immune responses against tumors.

Metal‐organic frameworks‐based nanomedicines to promote cancer immunotherapy: Recent advances and future directions

AbstractCancer immunotherapy uses the body's immune system to fight tumors by restoring natural antitumor responses. Metal‐organic frameworks (MOFs), characterized by their unique crystalline porous structures formed from metal ions linked by organic ligands, offer a promising solution. Recent studies have unveiled the potential of MOFs in cancer immunotherapy. The exceptional porosity and surface area, coupled with their extraordinary thermal and chemical stability, bring significant advantages for efficient drug loading and delivery of immunotherapeutic agents. The adaptability of MOFs further enhances the controlled release of immunotherapeutic drugs within target cells and increases tumor sensitivity to other therapies such as photodynamic, photothermal, and radiotherapy. This multifunctional carrier contributes to modulating the tumor microenvironment and reactivating antitumor immunity, providing a comprehensive strategy for cancer treatment. In this review, we summarize the applications of MOFs in immune checkpoint blockade, immunomodulator delivery, and cancer vaccine delivery, and discuss existing challenges in their use for immunotherapy. This discussion aims to offer insights for developing better treatments and enhancing the efficacy of immunotherapy.

Detrimental effect of an early exposure to antibiotics on the outcomes of immunotherapy in a multi-tumor cohort of patients.

Immune checkpoint inhibitors (ICI) have changed the therapeutic landscape of many solid tumors. Modulation of the intestinal microbiota by antibiotics (Abx) has been suggested to impact on ICI outcomes. Retrospective analysis of 475 patients with advanced solid tumors treated with ICI from 2015 to 2022. For each patient, the use of Abx was recorded from 1 month before ICI initiation until disease progression or death. The impact of Abx on objective response rates (ORR), disease control rates (DCR), progression-free survival (PFS), and overall survival (OS) was analyzed. Kaplan-Meier and log-rank tests were used to compare survival outcomes. In total 475 patients with advanced solid tumors were evaluated. Median age was 67.5 years and performance status (PS) was 0-1 in 84.6%. 66.5% of patients received Abx during treatment with ICI, mainly beta-lactams (53.8%) and quinolones (35.9%). The early exposure to Abx (from 60 days before to 42 days after the first cycle of ICI) was associated with a lower ORR (27.4% vs 39.4%; P < .01), a lower DCR (37.3% vs 57.4%; P < .001), lower PFS (16.8 m vs 27.8 m; HR 0.66; P < .001]) and lower OS (2.5 m vs 6.6 m; HR 0.68; P = .001]). The negative impact of Abx on OS and PFS was confirmed by a multivariable analysis. This effect was not observed among patients receiving Abx after 6 weeks from ICI initiation. Our results validate the hypothesis of a detrimental effect of an early exposure to Abxon the efficacy of ICI in a multi-tumor cohort of patients.

Small molecules from antibody pharmacophores (SMAbPs) as a hit identification workflow for immune checkpoints.

Small-molecule modulators of immune checkpoints are poised to revolutionize cancer immunotherapy. However, efficient strategies for hit identification are lacking. We introduce small molecules from antibody pharmacophores (SMAbPs), a workflow leveraging cocrystal structures of checkpoints with antibodies to create pharmacophore maps for virtual screening. Applying SMAbPs to five immune checkpoints yielded hits with submicromolar potency in both cell-free and cellular assays. Notably, SMAbPs identified the most potent T cell immunoglobulin and mucin-domain containing-3 and V-domain immunoglobulin suppressor of T cell activation (VISTA) inhibitors reported to date and first-in-class modulators of B and T lymphocyte attenuator, 4-IBB, and CD27. Targeting inhibitory and costimulatory checkpoints with hits identified through SMAbPs demonstrated remarkable in vivo antitumor activity, exemplified by MG-V-53 (VISTA inhibitor) and MG-C-30 (CD27 agonist), which significantly reduced tumor volumes in MC38 and EG7-OVA mouse models, respectively.

Enhancing the tissue penetration to improve sonodynamic immunotherapy for pancreatic ductal adenocarcinoma using membrane-camouflaged nanoplatform.

Sonodynamic therapy (SDT) is a promising strategy as an "in situ vaccine" to enhance activation of antitumor immune responses in solid tumors. However, the dense extracellular matrix (ECM) in pancreatic ductal adenocarcinoma (PDAC) lead to hypoxia and limited penetration of most drugs, aggravating the immunosuppressive tumor microenvironment and limiting the efficacy of synergistic sonodynamic immunotherapy. Therefore, it is essential to regulate ECM in order to alleviate tumor hypoxia and enhance the efficacy of sonodynamic immunotherapy for PDAC. The CPIM nanoplatform, consisting of a macrophage membrane-coated oxygen and drug delivery system (CM@PFOB-ICG-α-Mangostin), was synthesized using ultrasound and extrusion methods. The in vivo homologous targeting and hypoxia alleviation capabilities of CPIM were evaluated through near-infrared (NIR) imaging and photoacoustic (PA) imaging. The tumor growth inhibition potential and ability to reprogram the tumor microenvironment by the CPIM nanoplatform were also investigated. Co-delivery of α-Mangostin inhibits CAFs and enhances stromal depletion, thereby facilitating better infiltration of macromolecules. Additionally, the nanoemulsion containing perfluorocarbon (PFC) can target tumor cells and accumulate within them through homologous targeting. The US irradiation results in the rapid release of oxygen, serving as a potential source of sonodynamic therapy for hypoxic tumors. Moreover, CPIM reshapes the immunosuppressive microenvironment increasing the population of cytotoxic T lymphocytes (CTLs), and enhancing their anti-tumor immune response through the use of anti-PDL1 antibodies to block immune checkpoints. The present study offers a potential strategy for the co-delivery of oxygen and α-Mangostin, aiming to enhance the penetration of tumors to improve SDT. This approach effectively addresses the existing limitations of immune checkpoint blockade (ICB) treatment in solid tumors, while simultaneously boosting the immune response through synergistic sonodynamic immunotherapy.

Oral Lichenoid lesions induced by programmed cell death protein 1 and cytotoxic T-lymphocyte-associated protein 4 bispecific antibody: a case report

BackgroundCadonilimab is the first approved dual immune checkpoint inhibitor targeting programmed cell death protein 1 (PD-1) and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4), currently utilized for the treatment of various solid tumors. Oral mucosal adverse reactions, such as oral lichenoid lesions, represent one of the most prevalent immune-related adverse events associated with immune checkpoint antibodies. However, reports detailing oral side effects specifically linked to Cadonilimab are lacking. Documenting these side effects is essential to alert oncologists and stomatologists, facilitating timely intervention for affected patients.Case PresentationWe present a case involving a 35-year-old male patient diagnosed with hepatocellular carcinoma who received Cadonilimab following hepatectomy and subsequently developed extensive oral lichenoid lesions along with mucosal erosion at 13–14 weeks post-treatment initiation. A biopsy was conducted revealing immunohistochemical findings of CD3+, CD4+, CD8+, CD20 + lymphocytes, CD68 + macrophages, and α-SMA + myofibroblasts infiltrating the tissue of the oral lichenoid lesions. The patient’s oral lesions improved after administration of systemic and local glucocorticoid therapy alongside cessation of Cadonilimab treatment.ConclusionThis report marks the first documented instance of an oral adverse effect associated with Cadonilimab use. It underscores that administration of this agent may lead to significant lichenoid lesions and erosions within the oral cavity—an issue warranting increased vigilance from both oncologists and stomatologists.

MAZ promotes tumor proliferation and immune evasion in lung adenocarcinoma.

Lung adenocarcinoma (LUAD) is the most dominant histological subtype of lung cancer and one of the most lethal malignancies. The identification of novel therapeutic targets is required for the treatment of LUAD. Here, we showed that MYC-associated zinc-finger protein (MAZ) is upregulated in LUAD tissues. MAZ expression levels are inversely correlated with patient survival. Silencing of MAZ decreased tumor proliferation and the expression of pro-tumorigenic chemokines and Galectin-9 (Gal-9), an immune checkpoint molecule. The pro-tumorigenic chemokines and Gal-9 induce immune suppression by recruitment of myeloid cells and inhibition of T cell activation, respectively. Mechanistically, MAZ transcriptionally regulates KRAS expression and activates its downstream AKT-NF-κB signaling pathway, which is crucial for tumor progression and immune evasion. Additionally, in vivo animal models and bioinformatic analyses indicated that MAZ suppression could enhance the efficacy of immune checkpoint blockade (ICB) therapy for LUAD. Overall, our results suggest that MAZ plays an important role in regulating cell proliferation and immune evasion via KRAS/AKT/NF-κB signaling in LUAD. Our findings offer a candidate molecular target for LUAD therapy, with implications for improving the efficacy of ICB therapy.

Targeting VPS18 hampers retromer trafficking of PD-L1 and augments immunotherapy.

Immune checkpoint inhibitors targeting programmed cell death 1 (PD-1) or programmed cell death-ligand 1 (PD-L1) have achieved impressive antitumor clinical outcomes. However, the limited response rates suggest the incomplete understanding of PD-L1 regulation. Here, we demonstrate that vacuole protein sorting 11 and 18 (VPS11/18), two key players in vesicular trafficking, positively regulate PD-L1 and confer resistance to immune checkpoint blockade therapy. VPS11/18 interact with PD-L1 in endosome recycling accompanied by promoting PD-L1 glycosylation and protein stability. VPS18 deficiency enhances antitumor immune response. Pharmacological inhibition by VPS18 inhibitor RDN impaired PD-L1 member trafficking and protein stability. Combination treatment of RDN and anti-cytotoxic T lymphocyte-associated antigen 4 synergistically enhances antitumor efficacy in aggressive and drug-resistant tumors. RDN exerted lung-preferred distribution and good bioavailability, suggesting a favorable drug efficacy. Together, our study links VPS18/11-mediated trans-Golgi network recycling of PD-L1 and points to a promising treatment strategy for the enhancement of antitumor immunity.

Abstract A017: Identifying proliferative and immune-modulatory drivers of small cell lung cancer (SCLC)

Abstract Small cell lung cancer (SCLC) is a highly aggressive form of lung cancer that causes an estimated 200,000 patient deaths globally every year. Most (&amp;gt;70%) patients present with extensive stage (ES)-SCLC, and the disease primarily presents with a neuroendocrine (NE), immune-desert phenotype, with low expression of antigen-presenting machinery genes. Despite limited immune infiltration in the tumor, SCLC has reproducibly responded to immune checkpoint blockade. IMpower133 was a pivotal Phase III trial that added atezolizumab (anti-PD-L1) to platinum/etoposide chemotherapy for treatment of first-line ES-SCLC, which led to the first approval of an immune checkpoint blockade strategy in SCLC. While the inclusion of atezolizumab to the treatment regimen has extended the survival of some patients, SCLC remains an unmet medical need with a mOS of 12.3 months. Furthermore, we lack a deep molecular understanding of factors mediating response and resistance to standard of care therapies in SCLC. To understand the genetic drivers of SCLC that could be linked to immunotherapy resistance, we analyzed the matched whole-exome sequencing and RNA-seq data from baseline tumor samples collected from the IMpower133 trial. Previously, we applied the non-negative matrix factorization (NMF) approach to the RNA-seq data, which clustered patients into four subsets of SCLC, with varying degrees of immune infiltration, neuroendocrine program activation, and clinical benefit from immunotherapy. Notably, we identified an inflamed-neuroendocrine (I-NE) subset of patients that exhibit longer overall survival with chemoimmunotherapy compared to chemotherapy alone, and an inflamed-non-neuroendocrine (I-nonNE) subset of patients that did not show a similar benefit from the addition of immunotherapy to chemotherapy. Here, we interrogated the matched WES data for recurrent alterations that may identify subsets of tumors with distinct immunological features. We identified several genes whose alterations significantly affected the enrichment of immune-related gene signatures. In particular, we identified MANF and CSK, genes previously shown to be potential tumor suppressors, as genes whose alteration associates with an “immune desert” transcriptional program. Specifically, genetic deletions or low RNA expression was associated with significantly decreased gene expression of gene signatures associated with lymphocytes, macrophages, and antigen presentation machinery. These data suggest a potential mechanism by which commonly inactivated tumor suppressors may shape the “immune desert” phenotype of SCLC. Further work is needed to determine if and how these genes may directly or indirectly modulate the tumor-immune interaction. Citation Format: Myung Chang Lee, Velimir Gayevskiy, Stefanie Morris, Minu K Srivastava, Namrata S Patil, Stephen V Liu, Martin Reck, Sanjeev Mariathasan, David S Shames, David P MacPherson, Robert J Johnston, Barzin Y Nabet. Identifying proliferative and immune-modulatory drivers of small cell lung cancer (SCLC) [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor Immunology and Immunotherapy; 2024 Oct 18-21; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2024;12(10 Suppl):Abstract nr A017.

Abstract A033: Pro-inflammatory tumor cells drive CD4+ T cell localization within heterogeneous tumors

Abstract Immunotherapies such as immune checkpoint inhibitors (ICIs) have greatly improved patient outcomes in multiple tumor types, but ICIs have failed to achieve responses in many patients. Meta-analyses of patient cohorts treated with ICIs have observed that worse clinical outcomes are strongly correlated with high levels of intratumoral genetic heterogeneity (ITH). ITH occurs when tumor cells mutate as they divide, typically due to oxidative stress or DNA damage from rapid proliferation and continued carcinogenic insults, generating tumor subclones. However, the mechanisms by which ITH impairs the anti-tumor immune response are not fully understood. We propose a novel mechanism for how ITH in highly T cell-infiltrated inflamed tumors can adversely affect T cell behavior. We hypothesize that strongly pro-inflammatory tumor subclones secreting robust pro-inflammatory chemokine profiles can dominate T cell trafficking within the tumor, resulting in a weakened immune response against other tumor subclones. Using a murine squamous cell skin carcinoma (SCC) model, we have demonstrated that in immune-inflamed tumors, the spatial distribution and behavior of tumor-infiltrating T cells is influenced by ITH. A strongly pro-inflammatory tumor line expressing an endogenous RFP fluorophore was mixed with a weakly pro-inflammatory tumor line expressing an endogenous YFP fluorophore at a 1:1 ratio. The resulting tumors contained distinct RFP+ and YFP+ regions. These were analyzed by immunofluorescence (IF) and by manually dissecting the tumors and analyzing each region by flow cytometry. Flow cytometry analysis determined that the strongly pro-inflammatory RFP+ regions contained significantly more total T cells and CD4+ T cells than YFP+ regions. Furthermore, FoxP3- “conventional” CD4+ T cells were significantly more likely to be “terminal effector-like” CD44+CD62L- in RFP+ regions, and significantly more likely to be “naïve-like” CD62L+CD44- in YFP+ regions. IF analysis confirmed the preferential distribution of CD4+ T cells in RFP+ regions, and observed that this spatial pattern was evident as early as 11 days after subcutaneous injection. Notably, this localization trend did not occur with CD8+ T cells, which were evenly dispersed throughout the tumors. ELISA analysis of lysates of both tumor cell lines determined that the pro-inflammatory RFP+ cell line secretes significantly higher levels of the chemokine CCL5, which has been observed by other studies to selectively mediate CD4+ T cell chemotaxis. These results demonstrate that intratumoral CD4+ trafficking is shaped by the spatial distribution of specific tumor subclones, and suggest tumor cell chemokine signaling may directly mediate T cell spatial localization and behavior within tumors. Citation Format: Robert Letchworth, Savannah Hughes, Abigail Keku, Melissa Reeves. Pro-inflammatory tumor cells drive CD4+ T cell localization within heterogeneous tumors [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor Immunology and Immunotherapy; 2024 Oct 18-21; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2024;12(10 Suppl):Abstract nr A033.

Abstract A006: Tissue resident memory (TRM) T cells and dendritic cells form an in situ archetype for improved response to immune checkpoint therapy in metastatic melanoma

Abstract A006: Tissue resident memory (TRM) T cells and dendritic cells form an in situ archetype for improved response to immune checkpoint therapy in metastatic melanoma

Impact of senescence cell signature in patients with non-small cell carcinoma and melanoma receiving PD-L1/PD-1 inhibitors

Tumor cell senescence plays a crucial role in tumor immunity. We investigated whether the senescent cell signature (SCS) could predict prognosis in non-small cell carcinoma (NSCLC) and melanoma datasets treated with PD-L1/PD-1 inhibitors. Patients with high SCS expression exhibited elevated levels of interferon-gamma and T cell-inflamed signatures in three lung adenocarcinomas (LUAD), two squamous cell carcinoma (LUSC) and three melanoma datasets. The high SCS group was associated with PD-L1-related pathways such as IL6/JAK/STAT3 and TNF-alpha signaling via NF-kB in LUAD, LUSC, and melanoma datasets. A positive correlation was observed between several immune checkpoint markers and the SCS, indicating an immunosuppressive state in LUAD, LUSC and melanoma datasets. In patients treated with PD-1/PD-L1 inhibitors, a higher SCS was associated with a better prognosis, and a positive correlation between SCS and PD-L1 was observed in six independent NSCLC and three independent melanoma datasets. We used the LASSO Cox regression model to build a risk model focusing on the SCS genes that particularly predict prognosis. We confirmed that the model accurately predicts prognosis. However, the senescent immunohistochemical markers p16 and p21 could predict the response to PD-1/PD-L1 inhibitors in patients with LUSC and melanoma but not in patients with LUAD. SCS could serve as a valuable biomarker to complement PD-L1 expression in patients receiving PD-L1/PD-1 inhibitors.