IntroductionAdvances in single-cell and spatial profiling have enabled detailed characterization of heterogeneous samples, but analyzing this data remains challenging in settings involving multiple comparisons. While tools like UMAP and t-SNE are valuable for visualization, their stochastic, parameter-sensitive nature limits their use in longitudinal comparisons, treatment group analysis, and multicenter trials. Although OT was first described in the 19th century, the Sinkhorn algorithm makes it computationally tractable for high-dimensional data. By directly comparing distributions of cellular states, OT provides reproducible measures of change in high-dimensional space. This framework is amenable to integration with machine learning, including deep generative models.MethodsOT was applied to longitudinal data from a phase I trial of tocilizumab for cavitary malignancies (NCT 06016179). The current implementation makes use of expert-guided phenotypic population definitions and their relationships. An OT-based graph representation was created for baseline and follow-up samples. The graph layout was fixed across samples and computed from phenotypic relationships. In this implementation vertex radii are proportional to their relative abundance, allowing for rapid visual assessment of population-level increases and decreases. Graph edge thickness and color encode inter-population similarity based on the optimal transport (Sinkhorn) distance between marker expression distributions.ResultsThis representation enabled rapid identification of populations undergoing substantial change, such as the CD8+/IFNɣ+ population, which decreased from 63% to 17% of CD8+ T cells following treatment. Population changes across all fluorescence parameters were encoded in the graph edit distance (GED), which captures changes in population abundance and phenotypic shifts in marker space.DiscussionFuture implementations can combine this expert-guided approach with unbiased clustering algorithms to enhance scalability and cross-platform harmonization. In our recently initiated clinical trials, we will apply OT to identify key shifts in tumor, immune, and stromal cell states, summarizing patient trajectories and quantitatively supporting predictive models of treatment response. Potential applications include quantifying residual disease after chemotherapy, tracking immune activation during immunotherapy, and linking host–microbiome interactions to disease progression. This approach overcomes the limitations of traditional, local-structure-optimized tools (UMAP or t-SNE) to provide a comprehensive, longitudinal view of tumor evolution and treatment response.

Malignant pleural effusions (MPE) are a manifestation of advanced malignancy associated with poor prognosis, limited survival, and significant symptom burden. Current management is largely palliative and focused on fluid control rather than disease-modifying regional therapy. Malignant pleural effusions frequently contain abundant pleural infiltrating T (PIT) cells, representing an accessible and clinically feasible starting material for rapid autologous adoptive cellular therapy (ACT). RIOT-4 is a single-center, Phase I translational feasibility and safety clinical trial evaluating intrapleural administration of a locally manufactured PIT-derived ACT product generated using a closed GMP-compliant CliniMACS Prodigy® platform. The primary objective is to evaluate the safety and feasibility of intrapleural administration of a locally manufactured Fast TIL product in combination with low-dose intrapleural interleukin-2 (IL-2). Secondary objectives include ACT product characterization, immune profiling of pleural fluid and peripheral blood, T cell receptor (TCR) repertoire dynamics, cytokine/secretome analysis, spatial immune mapping, and preliminary clinical response assessment. This trial leverages institutional GMP cellular therapy infrastructure to generate a rapid, autologous Fast TIL product from pleural effusion as a novel compartmental immunotherapy strategy for patients with malignant pleural disease.

Abstract Background: Peritoneal carcinomatosis (PC) is a late manifestation of abdominopelvic malignancies, often resistant to current treatments due to an incomplete understanding of its biological drivers within the peritoneal immune microenvironment. This study aimed to identify actionable therapeutic targets for PC by analyzing peritoneal soluble mediators and cellular composition in patients. Building on existing evidence implicating IL-8 as a critical mediator of tumor-associated inflammation and immunosuppression in other cancers and preliminary data in PC, the study also evaluated IL-8 pathway inhibition in a preclinical model. Methods: Peritoneal tissue and fluid were collected from three patient groups: patients without benign conditions (n=15), cancer without PC (n=30), and confirmed PC (n=41). Immunohistochemistry was used to quantify immune cells in tissue and Luminex panels to analyze immune, inflammatory, and growth factors in peritoneal fluid. Statistical analyses identified group differences, correlations with disease burden (Peritoneal Cancer Index - PCI), and overall survival (OS). To assess therapeutic tractability of IL-8 axis blockade, a bioluminescent CT26-luc murine PC model was treated daily with the CXCR2 antagonist AZD5069 (100 mg/kg) or saline from day 0-9, with serial IVIS imaging, body-weight monitoring, and survival tracking through day 11. Results: PC tissue exhibited increased immune cell infiltration compared to non-PC groups, including elevated mast cells, neutrophils, CD4+ T cells, CD14+ monocytes, CD20+ B cells, and CD138+ plasma cells. Secretomic analysis of peritoneal fluid in PC revealed a dominant IL-6/IL-8-centered inflammatory signature, with increased GRO, IL-6, IL-8, CXCL10, IL-10, and TGF-β. This pattern supports pro-angiogenic, immunosuppressive, and stromal-activation signaling. Densities of CD4+, CD14+, CD20+, and CD138+ cells positively correlated with PCI, indicating progressive immune-stromal co-evolution with tumor burden. In human samples, neutrophil infiltration correlated with worse OS, while CD1a+ dendritic cell enrichment correlated with improved OS, underscoring the clinical relevance of the immunologic findings. In the murine model, AZD5069 demonstrated a therapeutic effect in 4 of 10 treated mice, suggesting potential efficacy of IL-8-axis targeting in specific patient subsets. Conclusion: PC is characterized by distinct immune cell infiltration and a significant IL-6/IL-8 cytokine network. Both neutrophil infiltration and the IL-6/IL-8 axis are associated with disease burden and patient survival, highlighting the IL-6/IL-8 axis as a relevant therapeutic target. Preclinical evidence supports its potential in specific patient groups. Further research is needed to identify predictive biomarkers for treatment response and translate these findings into clinical strategies. Citation Format: Christopher Sherry, Neda Dadgar, Zuqiang Liu, Yong Fan, Hyun Young Park, Ali Zaidi, Paige Mirsky, Oleksii Kucherenko, Albert Donnenberg, David L. Bartlett, Vera S. Donnenberg, Patrick Wagner. Integrated tissue and secretome profiling identifies an IL-6/IL-8-dominant immune phenotype in peritoneal carcinomatosis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 7952.

Current treatments for metastatic gastrointestinal malignancies have poor outcomes, necessitating a novel approach to treatment. Oncolytic therapy with vaccinia viruses has previously shown promising results in terms of safety and anti-tumor efficacy. In addition to direct viral cytotoxic effects, oncolytic therapy has the potential to stimulate adaptive immunity against infected tumor cells by altering the tumor microenvironment. The immunostimulatory effects of oncolytic vaccinia vectors have been maximized through the use of recombinant vectors encoding interleukin-2 (IL-2), a potent cytokine that signals T cell activity and proliferation. This report details the use of a novel oncolytic vaccinia vector- vvDD-hIL-2-RG-1-which encodes a rigid peptide-linked, membrane-bound form of IL-2, designed to maximize the local immunomodulatory activity following intratumoral injection. RIOT-3 is a phase 1, open-label, single-dose, dose-escalation trial investigating intratumoral injection of vvDD-hIL-2-RG-1. Up to 18 participants with metastatic gastrointestinal cancer who have failed systemic chemotherapy or immunotherapy will be enrolled. The primary study objective is to determine the safety and maximal tolerated and feasible doses for intratumoral injection via a 3 + 3 dose escalation design. Secondary objectives include quantifying viral replication, pharmacokinetics, and immune response to vvDD-hIL-2-RG-1 intratumoral injection, as well as efficacy assessment by RECIST criteria. Previous preclinical data in a murine model have demonstrated that IL-2-bound vaccinia oncolytic virus is safe and exerts dose-dependent anti-tumor activity. RIOT-3 will explore the application of this novel oncolytic viral approach in patients with advanced gastrointestinal malignancies who have failed conventional therapies. The trial is registered at ClinicalTrials.gov; NCT07001592 (registered May 6th, 2025).

Peritoneal carcinomatosis (PC) and malignant pleural effusions (MPE) are two common complications of cancers metastatic to the respective body cavities. A PC diagnosis indicates metastasis to the tissue lining the abdominal cavity and is most common in patients with gastrointestinal and gynecological cancers. It is often accompanied by ascites, an accumulation of serous fluid in the abdomen. MPE presents as the accumulation of fluid in the space between the lungs and chest wall. It is a common terminal event in patients diagnosed with breast cancer, lung cancer, lymphoma, and mesothelial cancers, and less commonly, in a wide variety of other epithelial cancers. Due to the aggressive nature of cavitary tumors, the outcome of current treatments for both PC and MPE remains bleak. Although PC and MPE are characteristically affected by different sets of primary tumors (lung/breast/mesothelioma for MPE and gynecologic/gastrointestinal for PC), their environments share common cytokines and cellular components. Owing to the unique cytokine and chemokine content, this environment promotes aggressive tumor behavior and paradoxically both recruits and suppresses central memory and effector memory T cells. The cellular and secretomic complexity of the cavitary tumor environment renders most currently available therapeutics ineffective but also invites approaches that leverage the robust T-cell infiltrate while addressing the causes of local suppression of anti-tumor immunity. Interactions between the heterogeneous components of the tumor environment are an area of active research. We highlight the roles of the immune cell infiltrate, stromal cells, and tumor cells, and the soluble products that they secrete into their environment. A more comprehensive understanding of the cavitary tumor environment can be expected to lead to better immunotherapeutic approaches to these devastating conditions.

Peritoneal carcinomatosis (PC) is a late-stage manifestation of abdominopelvic malignancies with poor prognosis and limited treatment options. Unique biochemical mechanisms within the peritoneal cavity play a key role in disease progression and resistance to therapy. Despite current therapies like systemic chemotherapy and cytoreductive surgery, patients frequently develop severe complications, including bowel obstruction, nutritional decline, and ascites, driving the need to address the pro-tumorigenic niche in the peritoneal cavity. The immune microenvironment in PC is marked by elevated proinflammatory mediators, such as IL-6 and IL-8, which skew the response toward innate rather than adaptive immune responses. IL-8 signaling, through its receptors CXCR1 and CXCR2, promotes neutrophil recruitment, chronic inflammation, angiogenesis, epithelial–mesenchymal transition, and immune evasion, making the IL-8/CXCR1/CXCR2 axis a potential therapeutic target in PC. Pre-clinical models provide evidence that IL-8 or CXCR1/CXCR2 blockade may be a valuable therapeutic strategy. IL-8 targeting agents such as monoclonal antibodies (BMS-986253) and small-molecule inhibitors (SX-682, AZD5069, navarixin) have shown efficacy in mitigating tumor growth and improving the efficacy of immune checkpoint inhibitors. Phase I and II trials have demonstrated encouraging safety profiles and preliminary efficacy when treating multiple abdominopelvic malignancies. In this review, we discuss the influence of the IL-8/CXCR1/CXCR2 axis within the peritoneal immune environment in PC and highlight recent work using IL-8 or CXCR1/CXCR2 blockade as a therapeutic strategy for PC. Continued research into the peritoneal immune microenvironment and the development of targeted therapies are essential for improving the management and prognosis of PC, potentially enhancing antitumor immunity and patient outcomes.

G protein-coupled receptors (GPCRs) represent the largest family of cell surface receptors. They orchestrate various signaling pathways, playing a central role in regulating various physiological and pathophysiological processes. Dysregulation of GPCR signaling has been intricately linked to cancer pathogenesis, including tumor growth, angiogenesis, metastasis, and immune modulation. Biased GPCR signaling occurs when a ligand preferentially activates one signaling pathway over another, leading to distinct cellular outcomes. In cancer, biased GPCR signaling represents a complex, dynamic phenomenon, significantly influencing cancer development, progression, and treatment resistance. This chapter reviews recent advances in our understanding of GPCR biased signaling in various aspects of cancer biology and explores its therapeutic potential. Given the fragmented nature of existing evidence, we integrate available literature with findings from our own proteomics studies on GPCR and β-arrestin function to provide a preliminary framework for understanding β-arrestin-mediated signaling in cancer. While this overview may capture only a limited snapshot of the broader landscape, it provides a valuable foundation for generating new hypotheses and guiding future research and drug discovery efforts in oncology.

Breast cancer (BC) metastatic to the pleura is uniformly fatal with a median survival of six months and quality of life that is diminished by dyspnea, pain and discomfort. There are currently no curative treatments once malignant pleural effusions (MPE) have occurred. Despite significant clinical progress in immuno-oncology, there has been almost no change in survival or quality of life for patients with MPE. We have shown that BC MPE are characterized by a distinct and complex pleural secretome that varies little between breast cancer subtypes. Our studies on freshly isolated pleural T cells (PIT) from breast cancer MPE of all subtypes indicate that these cells are quiescent rather than exhausted, and poised to mount potent anti-autologous tumor effector responses, but locally suppressed by the pleural environment. To date, there are no reports on cytokine secretion and immune checkpoint expression in pleural T cells isolated from patients with invasive lobular carcinoma (ILC) metastatic to the pleura. In this abstract we show that freshly isolated pleural T cells from patients with ILC secrete T-cell effector cytokines (IL-2 or IFNγ), are not exhausted (lack or have low expression of PD1, TIM3, LAG3, TIGIT, CTLA4) and a minority express CD137/4-1BB activation/signal transduction molecule, critical to anti-tumor effectors. Consistent with our findings in BC grouped by HR status, the 8 most prevalent cytokines in the pleural secretome (CXCL10, CCL2, sIL-6Rα, IL-6, CXCL1, TGFβ, CCL11, IL-10) are indistinguishable between ILC and IDC. However, ILC cases clustered together in hierarchical clustering across 40 measured cytokines, due chiefly to a paucity of G-CSF, VEGF, IL-7, and an excess of IL-4. The data suggest that ILC PIT are immunologically competent when removed from their suppressive environment and can be used to generate an adoptive cellular therapeutic. Citation Format: Vera Donnenberg, Albert Donnenberg, James Luketich, Shannon Puhalla, Christie Hilton, David Bartlett. PLEURAL T CELLS FROM PATIENTS WITH METASTATIC INVASIVE LOBULAR CARCINOMA PRODUCE EFFECTOR CYTOKINES AND MOUNT ANTI-TUMOR IMMUNITY [abstract]. In: Proceedings of the San Antonio Breast Cancer Symposium 2024; 2024 Dec 10-13; San Antonio, TX. Philadelphia (PA): AACR; Clin Cancer Res 2025;31(12 Suppl):Abstract nr P3-09-24.

Biological materials composed of extracellular matrix (ECM) or its components have been successfully used for tissue repair and reconstruction. Preclinical studies, along with a cohort study following stage T1A esophageal adenocarcinoma (EAC) resection, have shown that ECM biomaterials can restore esophageal mucosa and submucosa without cancer recurrence. However, the molecular mechanisms underlying these effects remain largely unexplored. The present study investigates the in vitro effects of ECM degradation products from nonmalignant esophageal (eECM) and urinary bladder (ubECM) sources on EAC cell proliferation, migration, and associated signaling pathways. Both eECM and ubECM significantly inhibited OE33 cell proliferation, with eECM exhibiting a stronger effect-reducing proliferation to 25% at 24 h and 7% at 72 h compared with pepsin control (p < 0.001). A high-throughput cell surface marker screen followed by gene and protein expression analysis revealed that both ECM sources downregulated CD164 and CXCR4, reducing CXCR4 protein levels by approximately 50% (p = 0.006 for eECM, p = 0.007 for ubECM). Notably, only eECM significantly suppressed OE33 cell migration (p ≤ 0.0001) and downregulated bone morphogenetic protein 4 BMP4 expression, along with its downstream targets pSMAD1/5/8, ID2, and SNAI2, thereby reducing epithelial-mesenchymal transition. These findings support the concept that biochemical cues from nonmalignant ECM modulate neoplastic cell behavior. Given the involvement of PI3K-Akt and BMP4 signaling in EAC progression, ECM-based strategies may warrant further investigation as potential therapeutic approaches following esophageal cancer resection.

BACKGROUND AIMS:Cancers of many different tissue origins can metastasize to the pleura, a space with a unique immune environment that predisposes to aggressive tumor behavior and the development of effusions, an exudative leakage of serous fluid accompanied by an immune infiltrate. Effusions are drained therapeutically to relieve dyspnea, often several times per week. Characteristically, they contain 50-1000 × 106 viable pleural T cells (PITs), which can be reliably activated and expanded in culture, making them an ideal source for generation of a cellular therapeutic. We sought to determine the feasibility of a Good Manufacturing Practice-compliant, rapidly manufactured adoptive cellular therapeutic from pleural-infiltrating T cells and to determine the cytolytic activity against autologous tumor, cytokine secretion profile, and immune check point molecule (ICM) expression. METHODS:Six products were generated from consecutively collected malignant pleural effusions (MPEs) drained from patients with breast (4) or non-small cell lung (2) cancer metastatic to the pleura. CD4+ and CD8+ cells were immunomagnetically selected, stimulated with anti-CD3/anti-CD28 and expanded in the presence of interleukin (IL)-7 and IL-15 (12.5 ng/mL each) using the Miltenyi CliniMACS Prodigy device. Cells were cultured for 8- 12 days. Cytokines were assayed in the MPE and in the culture medium before harvest using a multiplexed bead assay. Cytolytic activity of the final cellular product formulation against an autologous tumor was measured in a 4-hour killing assay by lactate dehydrogenase release. T-cell content, ICM expression and intracellular interferon ɣ were assessed by flow cytometry. RESULTS:All MPEs successfully generated products containing 0.7 to 3.2 × 109 viable T cells. All final products showed no growth in bacterial or fungal cultures. T-cell purity was 98.3 ± 1.7% (mean, standard deviation), viability was 97.6 ± 1.7% and T-cell fold expansion was 14.3 ± 10.6. Twenty cytokines (excluding IL-7 and IL-15) were present in the culture supernatants at ≥10 pmol/L. These include granzyme B, interferon-ɣ, IL-13, perforin, granulocyte-macrophage colony-stimulating factor and tumor necrosis factor-α. In the final cellular product formulation, 69 ± 28% of CD4+ T cells, and 75 ± 27% of CD8+ T-cells produced interferon-ɣ without additional stimulation. ICM expression was well correlated between CD4+ and CD8+ T cells and was relatively low, with TIGIT (44.6 ± 10.9%) and programmed cell death protein 1(21.1 ± 6.7%) being the highest. All products evidenced cytolytic activity against an autologous tumor, with maximal lysis ranging from 19.4% to 100% and cytolytic indices ranging from 4.3 to 21.1. CONCLUSIONS:We conclude that Fast tumor-infiltrating lymphocytes (Fast TIL), an adoptive cellular therapeutic generated from drained MPEs, can be rapidly and reliably manufactured using the Prodigy system. The products have demonstrable in vitro effector activity against an autologous tumor. Expression of interferon-ɣ in the majority of cells, without accompanying elevated expression of ICM, suggests that the cells have not been exhausted during expansion. Based in part on the results presented here, the US Food and Drug Administration has issued Investigational New Drug status (IND # 30892) for the rapid manufacture of PIT-based cellular therapeutic (Fast TIL), paving the way for a first-in-human clinical trial (supported by CDMRP-TTSA CA230972). We plan to infuse this product intrapleurally, accompanied by low-dose intrapleural IL-2 with the expectation that infused cells will immediately encounter tumor antigens, continue to expand in the pleural space, and migrate to the peripheral circulation.

BackgroundMany cancers metastasize to the pleura, resulting in effusions that cause dyspnea and discomfort. Regardless of the tissue of origin, pleural malignancies are aggressive and uniformly fatal, with no treatment shown to prolong life. The pleural mesothelial monolayer is joined by tight junctions forming a contained bioreactor-like space, concentrating cytokines and chemokines secreted by the mesothelium, tumor, and infiltrating immune cells. This space represents a unique environment that profoundly influences tumor and immune cell behavior. Defining the pleural secretome is an important step in the rational development localized intrapleural immunotherapy.MethodWe measured cytokine/chemokine content of 252 malignant pleural effusion (MPE) samples across multiple cancers using a 40-analyte panel and Luminex multiplexing technology.ResultsEleven analytes were consistently present in concentrations ≥ 10.0 pM: CXCL10/IP10 (geometric mean = 672.3 pM), CCL2/MCP1 (562.9 pM), sIL-6Rα (403.1 pM), IL-6 (137.6 pM), CXCL1/GRO (80.3 pM), TGFβ1 (76.8 pM), CCL22/MDC (54.8 pM), CXCL8/IL-8 (29.2 pM), CCL11/Eotaxin (12.6 pM), IL-10 (11.3 pM), and G-CSF (11.0 pM). All are capable of mediating chemotaxis, promotion of epithelial to mesenchymal transition, or immunosuppression, and many of are reportedly downstream of a pro-inflammatory cytokine cascade mediated by cytokine IL-6 and its soluble receptor.ConclusionThe data indicate high concentrations of several cytokines and chemokines across epithelial cancers metastatic to the pleura and support the contention that the pleural environment is the major factor responsible for the clinical course of MPE across cancer types. A sIL-6Rα to IL-6 molar ratio of 2.7 ensures that virtually all epithelial, immune and vascular endothelial cells in the pleural environment are affected by IL-6 signaling. The central role likely played by IL-6 in the pathogenesis of MPE argues in favor of a therapeutic approach targeting the IL-6/IL-6R axis.

BackgroundIntra-tumoral immunotherapy has shown potential in treating advanced cancers. Delivery challenges have limited exploration of these modalities in intra-abdominal tumors. In this study, we explore the safety of injecting intra-abdominal tumors with lipopolysaccharide (LPS) from Escherichia coli 0113. This agonist of toll-like receptor 4 (TLR4) holds promise as an agent to enhance the anti-tumor immune response within the tumor microenvironment.MethodsThis Phase I study will recruit adult patients with peritoneal metastases from gastrointestinal primary malignancies who have at least two suitable intra-abdominal soft tissue tumors for injection. LPS will be administered as a single 1μg dose during diagnostic laparoscopy in patients in whom a subsequent interval laparotomy is planned. A control injection of saline will be injected into a second lesion. Primary outcome is safety, with secondary outcomes being biomarkers of the tumor immune microenvironment in pre- and post-treatment biopsies.ResultsThe primary endpoint is to determine the safety (frequency and nature of adverse events) following intra-tumoral LPS injection. Adverse events will be classified using Common Terminology Criteria for Adverse Events. Secondary endpoints include cellular and molecular biomarkers of immune response. The study will proceed until twelve patients have completed the protocol.DiscussionPatients undergoing standard-of-care laparoscopy in preparation for interval cytoreductive surgery may be ideal candidates for intra-tumoral immunotherapy. This study seeks to establish the safety of using E. coli LPS for injection into intra-abdominal tumors and to establish precedent for interval tumor immune microenvironment assessment as a window-of-opportunity concept in the context of abdominal metastatic disease.Trial RegistrationThe trial is registered at Clinical Trials.gov; NCT05751837 (registered February 28th, 2023).

BackgroundMalignant pleural effusions (MPE) and malignant ascites (MA) are serious complications of advanced cancer, marked by debilitating symptoms and limited treatment options. Based on a wealth of previous literature implicating the cytokine IL-6 as a central mediator in the pathogenesis of MPE and MA, the Regional Immuno-Oncology Trial 2 (RIOT-2) clinical protocol was developed to explore intra-cavitary delivery of tocilizumab, an IL-6 receptor antagonist, as treatment for these conditions.MethodsThis phase I clinical trial (NCT 06016179) is being conducted to assess the safety and pharmacokinetics of intra-cavitary tocilizumab administration to patients with MPE and MA. Eligible patients are those with pleural effusion or peritoneal ascites due to metastatic cancer who are scheduled to undergo standard-of-care catheter placement for pleural or peritoneal drainage. Following catheter placement, patients will receive a starting dose of tocilizumab 0.5 µg/mL via intra-pleural or intra-peritoneal implantable catheters. Weekly escalating doses of tocilizumab will be given over four weeks. Primary endpoints are frequency and type of adverse events, while secondary endpoints include pharmacokinetic and immunological parameters. This single-center study will proceed until 12 patients have been treated.DiscussionInhibition of the IL-6 signaling pathway with tocilizumab is hypothesized to be a rational mitigating treatment strategy for the maladaptive intra-cavitary immune environment in patients with MPE and MA. The RIOT-2 study aims to assess the safety of intra-cavitary tocilizumab therapy, administered via indwelling catheters. Pharmacologic and translational immunologic findings generated by this study could pave the way for future research into clinical applications of intra-cavitary immunotherapy.Trial RegistrationThe trial is registered at ClinicalTrials.gov; NCT06016179 (registered on August 29th, 2023).

Peritoneal carcinomatosis (PC) is a complex manifestation of abdominal cancers, with a poor prognosis and limited treatment options. Recent work identifying high concentrations of the cytokine interleukin-6 (IL-6) and its soluble receptor (sIL-6-Rα) in the peritoneal cavity of patients with PC has highlighted this pathway as an emerging potential therapeutic target. This review article provides a comprehensive overview of the current understanding of the potential role of IL-6 in the development and progression of PC. We discuss mechansims by which the IL-6 pathway may contribute to peritoneal tumor dissemination, mesothelial adhesion and invasion, stromal invasion and proliferation, and immune response modulation. Finally, we review the prospects for targeting the IL-6 pathway in the treatment of PC, focusing on common sites of origin, including ovarian, gastric, pancreatic, colorectal and appendiceal cancer, and mesothelioma.

Peritoneal carcinomatosis originating from gastric/gastroesophageal junction cancer (GC-PC) occurs in a defined subset of gastric cancer patients with unique clinical, pathologic, molecular and immunologic characteristics that create significant obstacles to effective treatment with modern therapy. Although systemic chemo- and immuno- therapy have yielded disappointing results in GC-PC, recent advances in the characterization of GC-PC and peritoneal immune biology present new opportunities for targeted therapeutics. In this review article, we discuss the distinct properties of GC-PC and the peritoneal immune environment as they pertain to current and investigative treatment strategies. We discuss pre-clinical studies and clinical trials relevant to the modulation of the peritoneal environment as a therapeutic intervention in GC-PC. Finally, we present a road map for future combinatorial strategies based on the conception of the peritoneal cavity as a bioreactor. Within this isolated compartment, prevailing immunosuppressive conditions can be altered through regional interventions toward an adaptive phenotype that would support the effectiveness of regionally delivered cellular therapy products. It is hoped that novel combination strategies would promote efficacy not only in the sequestered peritoneal environment, but also via migration into the circulation of tumor-reactive lymphocytes to produce durable systemic disease control, thereby improving oncologic outcome and quality of life in patients with GC-PC.

IntroductionTreatment options for patients with malignant pleural effusions (MPE) are limited due, at least in part, to the unique environment of the pleural space, which drives an aggressive tumor state and governs the behavior of infiltrating immune cells. Modulation of the pleural environment may be a necessary step toward the development of effective treatments. We examine immune checkpoint molecule (ICM) expression on pleural T cells, the secretomes of pleural fluid, pleural infiltrating T cells (PIT), and ability to activate PIT ex vivo.MethodsICM expression was determined on freshly drained and in vitro activated PIT from breast, lung and renal cell cancer. Secretomics (63 analytes) of activated PIT, primary tumor cultures and MPE fluid was determined using Luminex technology. Complementary digital spatial proteomic profiling (42 analytes) of CD45+ MPE cells was done using the Nanostring GeoMx platform. Cytolytic activity was measured against autologous tumor targets.ResultsICM expression was low on freshy isolated PIT; regulatory T cells (T-reg) were not detectable by GeoMx. In vitro activated PIT coexpressed PD-1, LAG-3 and TIGIT but were highly cytotoxic against autologous tumor and uniquely secreted cytokines and chemokines in the > 100 pM range. These included CCL4, CCL3, granzyme B, IL-13, TNFα, IL-2 IFNγ, GM-CSF, and perforin. Activated PIT also secreted high levels of IL-6, IL-8 and sIL-6Rα, which contribute to polarization of the pleural environment toward wound healing and the epithelial to mesenchymal transition. Addition of IL-6Rα antagonist to cultures reversed tumor EMT but did not alter PIT activation, cytokine secretion or cytotoxicity.DiscussionDespite the negative environment, immune effector cells are plentiful, persist in MPE in a quiescent state, and are easily activated and expanded in culture. Low expression of ICM on native PIT may explain reported lack of responsiveness to immune checkpoint blockade. The potent cytotoxic activity of activated PIT and a proof-of-concept clinical scale GMP-expansion experiment support their promise as a cellular therapeutic. We expect that a successful approach will require combining cellular therapy with pleural conditioning using immune checkpoint blockers together with inhibitors of upstream master cytokines such as the IL-6/IL-6R axis.

Background: Fat grafting is an effective treatment for craniofacial deformities. Stromal vascular fraction (SVF) is a concentrated form of adipose derived stem cells that can be isolated from fat. The aim of this clinical trial was to assess the impact of SVF enrichment on craniofacial fat grafting. Methods: Twelve subjects with at least two regions of craniofacial volume deficit were enrolled, and they underwent fat grafting with SVF-enriched or standard fat grafting to each area. All patients had bilateral malar regions injected with SVF-enriched graft on one side and control standard fat grafting to the contralateral side. Outcome assessments included demographic information, volume retention determined by CT scans, SVF cell populations assessed by flow cytometry, SVF cell viability, complications, and appearance ratings. Follow-up was 9 months. Results: All patients had improvement in appearance. There were no serious adverse events. There was no significant difference in volume retention between the SVF-enriched and control regions overall (50.3% versus 57.3%, P = 0.269) or comparing malar regions (51.4% versus 56.7%, P = 0.494). Patient age, smoking status, obesity, and diagnosis of diabetes did not impact volume retention. Cell viability was 77.4% ± 7.3%. Cellular subpopulations were 60.1% ± 11.2% adipose derived stem cells, 12.2 ± 7.0% endothelial cells, and 9.2% ± 4.4% pericytes. A strong positive correlation was found between CD146+ CD31-pericytes and volume retention (R = 0.863, P = 0.027). Conclusions: Autologous fat transfer for reconstruction of craniofacial defects is effective and safe, leading to reliable volume retention. However, SVF enrichment does not significantly impact volume retention.