Phase II study to determine the anti-tumor activity and safety of simlukafusp alfa (FAP-IL2v) combined with atezolizumab in esophageal cancer.

PURPOSE: Reported here are results from the esophageal squamous cell carcinoma (SCC) cohort of a Phase II, non-comparative, basket study, evaluating the anti-tumor activity and safety of FAP-IL2v plus atezolizumab in patients with advanced/metastatic solid tumors (NCT03386721). EXPERIMENTAL DESIGN: Eligible patients had an Eastern Cooperative Oncology Group performance status of 0-1; measurable metastatic, persistent, or recurrent esophageal SCC; progression on ≥1 prior therapy; and were checkpoint inhibitor naive. Patients received FAP-IL2v 10 mg plus atezolizumab 1200 mg intravenously every 3 weeks, or FAP-IL2v weekly for 4 weeks, then every 2 weeks, plus atezolizumab 840 mg intravenously every 2 weeks. Primary endpoint was investigator-assessed objective response rate (ORR). RESULTS: In the response-evaluable population (N=34), best confirmed ORR was 20.6% (95% confidence interval [CI]: 10.4-36.8) with a complete response (CR) seen in one patient and partial responses (PR) in six patients. Disease control rate was 44.1% (CR=2.9%; PR=17.6%; stable disease [SD]=23.5%) and median duration of response was 10.1 months (95% CI: 5.6-26.7). Median progression-free survival was 1.9 months (95% CI: 1.8-3.7). Analysis of response by PD-L1 expression (Ventana SP263) resulted in an ORR of 26.7 % for patients with PD-L1-positive tumors (tumor area positivity [TAP] cut-off ≥1%; n=15) and 7.1% for patients with PD-L1-negative tumors (TAP cut-off <1%; n=14). Overall, the treatment combination was tolerable and adverse events were consistent with the known safety profiles of each drug. CONCLUSIONS: FAP-IL2v plus atezolizumab demonstrated clinical activity and was tolerable in patients with previously treated esophageal SCC.

Signature-driven repurposing of Midostaurin for combination with MEK1/2 and KRASG12C inhibitors in lung cancer.

Drug combinations are key to circumvent resistance mechanisms compromising response to single anti-cancer targeted therapies. The implementation of combinatorial approaches involving MEK1/2 or KRASG12C inhibitors in the context of KRAS-mutated lung cancers focuses fundamentally on targeting KRAS proximal activators or effectors. However, the antitumor effect is highly determined by compensatory mechanisms arising in defined cell types or tumor subgroups. A potential strategy to find drug combinations targeting a larger fraction of KRAS-mutated lung cancers may capitalize on the common, distal gene expression output elicited by oncogenic KRAS. By integrating a signature-driven drug repurposing approach with a pairwise pharmacological screen, here we show synergistic drug combinations consisting of multi-tyrosine kinase PKC inhibitors together with MEK1/2 or KRASG12C inhibitors. Such combinations elicit a cytotoxic response in both in vitro and in vivo models, which in part involves inhibition of the PKC inhibitor target AURKB. Proteome profiling links dysregulation of MYC expression to the effect of both PKC inhibitor-based drug combinations. Furthermore, MYC overexpression appears as a resistance mechanism to MEK1/2 and KRASG12C inhibitors. Our study provides a rational framework for selecting drugs entering combinatorial strategies and unveils MEK1/2- and KRASG12C-based therapies for lung cancer.

A first-in-human study of the fibroblast activation protein-targeted, 4-1BB agonist RO7122290 in patients with advanced solid tumors.

This first-in-human study evaluated RO7122290, a bispecific fusion protein carrying a split trimeric 4-1BB (CD137) ligand and a fibroblast activation protein α (FAP) binding site that costimulates T cells for improved tumor cell killing in FAP-expressing tumors. Patients with advanced or metastatic solid tumors received escalating weekly intravenous doses of RO7122290 as a single agent (n = 65) or in combination with a 1200-milligram fixed dose of the anti-programmed death-ligand 1 (anti-PD-L1) antibody atezolizumab given every 3 weeks (n = 50), across a tested RO7122290 dose range of 5 to 2000 milligrams and 45 to 2000 milligrams, respectively. Three dose-limiting toxicities were reported, two at different RO7122290 single-agent doses (grade 3 febrile neutropenia and grade 3 cytokine release syndrome) and one for the combination (grade 3 pneumonitis). No maximum tolerated dose was identified. The pharmacokinetic profile of RO7122290 suggested nonlinearity in elimination. The observed changes in peripheral and tissue pharmacodynamic (PD) biomarkers were consistent with the postulated mechanism of action. Treatment-induced PD changes included an increase in proliferating and activated T cells in peripheral blood both in the single-agent and combination arms. Increased infiltration of intratumoral CD8+ and Ki67+CD8+ T cells was observed for both treatment regimens, accompanied by the up-regulation of T cell activation genes and gene signatures. Eleven patients experienced a complete or partial response, six of whom were confirmed to be immune checkpoint inhibitor naive. These results support further evaluation of RO7122290 in combination with atezolizumab or other immune-oncology agents for the treatment of solid tumors.

Therapeutic drug monitoring of neoadjuvant mFOLFIRINOX in resected pancreatic ductal adenocarcinoma.

BACKGROUND: Despite a potentially curative treatment, the prognosis after upfront surgery and adjuvant chemotherapy for patients with resectable pancreatic ductal adenocarcinoma (PDAC) is poor. Modified FOLFIRINOX (mFOLFIRINOX) is a cornerstone in the systemic treatment of PDAC, including the neoadjuvant setting. Pharmacokinetic-guided (PKG) dosing has demonstrated beneficial effects in other tumors, but scarce data is available in pancreatic cancer. METHODS: Forty-six patients with resected PDAC after mFOLFIRINOX neoadjuvant approach and included in an institutional protocol for anticancer drug monitoring were retrospectively analyzed. 5-Fluorouracil (5-FU) dosage was adjusted throughout neoadjuvant treatment according to pharmacokinetic parameters and Irinotecan (CPT-11) pharmacokinetic variables were retrospectively estimated. RESULTS: By exploratory univariate analyses, a significantly longer progression-free survival was observed for patients with either 5-FU area under the curve (AUC) above 28 mcg·h/mL or CPT-11 AUC values below 10 mcg·h/mL. In the multivariate analyses adjusted by age, gender, performance status and resectability after stratification according to both pharmacokinetic parameters, the risk of progression was significantly reduced in patients with 5-FU AUC ≥28 mcg·h/mL [HR = 0.251, 95% CI 0.096-0.656; p = 0.005] and CPT-11 AUC <10 mcg·h/mL [HR = 0.189, 95% CI 0.073-0.486, p = 0.001]. CONCLUSIONS: Pharmacokinetically-guided dose adjustment of standard chemotherapy treatments might improve survival outcomes in patients with pancreatic ductal adenocarcinoma.

Liver Resection and Transplantation Following Yttrium-90 Radioembolization for Primary Malignant Liver Tumors: A 15-Year Single-Center Experience.

Radioembolization (RE) may help local control and achieve tumor reduction while hypertrophies healthy liver and provides a test of time. For liver transplant (LT) candidates, it may attain downstaging for initially non-candidates and bridging during the waitlist. METHODS: Patients diagnosed with HCC and ICC treated by RE with further liver resection (LR) or LT between 2005-2020 were included. All patients selected were discarded for the upfront surgical approach for not accomplishing oncological or surgical safety criteria after a multidisciplinary team assessment. Data for clinicopathological details, postoperative, and survival outcomes were retrospectively reviewed from a prospectively maintained database. RESULTS: A total of 34 patients underwent surgery following RE (21 LR and 13 LT). Clavien-Dindo grade III-IV complications and mortality rates were 19.0% and 9.5% for LR and 7.7% and 0% for LT, respectively. After RE, for HCC and ICC patients in the LR group, 10-year OS rates were 57% and 60%, and 10-year DFS rates were 43.1% and 60%, respectively. For HCC patients in the LT group, 10-year OS and DFS rates from RE were 51.3% and 43.3%, respectively. CONCLUSION: Liver resection after RE is safe and feasible with optimal short-term outcomes. Patients diagnosed with unresectable or high biological risk HCC or ICC, treated with RE, and rescued by LR may achieve optimal global and DFS rates. On the other hand, bridging or downstaging strategies to LT with RE in HCC patients show adequate recurrence rates as well as long-term survival.

LAMC2 Regulates Key Transcriptional and Targetable Effectors to Support Pancreatic Cancer Growth.

PURPOSE: The identification of pancreatic ductal adenocarcinoma (PDAC) dysregulated genes may unveil novel molecular targets entering inhibitory strategies. Laminins are emerging as potential targets in PDAC given their role as diagnostic and prognostic markers. Here, we investigated the cellular, functional, and clinical relevance of LAMC2 and its regulated network, with the ultimate goal of identifying potential therapies. EXPERIMENTAL DESIGN: LAMC2 expression was analyzed in PDAC tissues, a panel of human and mouse cell lines, and a genetically engineered mouse model. Genetic perturbation in 2D, 3D, and in vivo allograft and xenograft models was done. Expression profiling of a LAMC2 network was performed by RNA-sequencing, and publicly available gene expression datasets from experimental and clinical studies examined to query its human relevance. Dual inhibition of pharmacologically targetable LAMC2-regulated effectors was investigated. RESULTS: LAMC2 was consistently upregulated in human and mouse experimental models as well as in human PDAC specimens, and associated with tumor grade and survival. LAMC2 inhibition impaired cell cycle, induced apoptosis, and sensitized PDAC to MEK1/2 inhibitors (MEK1/2i). A LAMC2-regulated network was featured in PDAC, including both classical and quasi-mesenchymal subtypes, and contained downstream effectors transcriptionally shared by the KRAS signaling pathway. LAMC2 regulated a functional FOSL1-AXL axis via AKT phosphorylation. Furthermore, genetic LAMC2 or pharmacological AXL inhibition elicited a synergistic antiproliferative effect in combination with MEK1/2is that was consistent across 2D and 3D human and mouse PDAC models, including primary patient-derived organoids. CONCLUSIONS: LAMC2 is a molecular target in PDAC that regulates a transcriptional network that unveils a dual drug combination for cancer treatment.

Immunotherapies for hepatocellular carcinoma and intrahepatic cholangiocarcinoma: Current and developing strategies.

Liver cancer including hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (iCCA) is the third leading cause of cancer-related deaths worldwide. HCC arises from hepatocyte or hepatic stem cells, while iCCA originates from biliary epithelial cells, and the respective biological context are very different. Despite screening programs, the diagnosis of liver cancer is in most cases made when curative treatments such as surgery or ablation are not possible. In 2020, after a decade of using only tyrosine kinase inhibitors (TKI), a combination of an immune-check point inhibitor (ICI) and a VEGF antagonist proved superior to a TKI as first line therapy of advanced HCC. In 2022, the addition of an ICI to standard chemotherapy demonstrated an improvement of patient survival in iCCA. Moreover, ICI offer an unprecedented rate of durable responses to HCC and iCCA patients. Nevertheless, still two thirds of patients do not respond to ICI-based combinations, and research efforts are focused on deciphering the mechanisms of immune evasion of these lethal cancers. Reliable predictive and prognostic biomarkers are still lacking, but the molecular phenotyping of the tumor microenvironment is currently providing potential candidates for patient stratification. In this review, we will summarize the current knowledge on the immune biology of the liver, the discovery of cell-intrinsic and immune cell-mediated mechanisms of immune evasion by means of high-resolution single cell data, the main targets of current immunotherapy approaches, and the recent milestones in immunotherapy of HCC and iCCA.

Clinico-Genomic Characterization of Patients with Metastatic Urothelial Carcinoma in Real-World Practice Identifies a Novel Bladder Immune Performance Index (BIPI).

PURPOSE: This retrospective analysis of the largest available clinico-genomic database used de-identified patient-level electronic health record-derived real-world data (RWD) combined with FoundationOne comprehensive genomic profiling (CGP) to characterize patients with metastatic urothelial carcinoma (mUC) treated in the real-world setting, detect potential biomarkers, and develop a bladder immune performance index (BIPI). EXPERIMENTAL DESIGN: Patients with mUC who started front-line single-agent immune checkpoint inhibitors (ICI) and an unmatched group treated with front-line platinum-based chemotherapy between January 1, 2011, and September 30, 2019, were selected. Clinical and genomic data were correlated with overall survival (OS). A novel BIPI predicting outcome with ICIs was developed using machine learning methods and validated using data from a phase II trial (NCT02951767). RESULTS: In ICI-treated patients (n = 118), high tumor mutational burden (≥10 mutations/megabase) was associated with improved OS (HR, 0.58; 95% CI, 0.35-0.95; P = 0.03). In chemotherapy-treated patients (n = 268), those with high APOBEC mutational signature had worse OS (HR, 1.43; 95% CI, 1.06-1.94; P = 0.02). Neither FGFR3 mutations nor DNA damage-repair pathway alterations were associated with OS. A novel BIPI combining clinical and genomic variables (nonmetastatic at initial diagnosis, normal or above normal albumin level at baseline, prior surgery for organ-confined disease, high tumor mutational burden) identified ICI-treated patients with longest OS and was validated in an independent dataset. CONCLUSIONS: Contemporary RWD including FoundationOne CGP can be used to characterize outcomes in real-world patients according to biomarkers beyond PD-L1. A validated, novel clinico-genomic BIPI demonstrated satisfactory prognostic performance for OS in patients with mUC receiving front-line ICI therapy.

Cholangiocarcinoma landscape in Europe: Diagnostic, prognostic and therapeutic insights from the ENSCCA Registry.

BACKGROUND & AIMS: Cholangiocarcinoma (CCA) is a rare and heterogeneous biliary cancer, whose incidence and related mortality is increasing. This study investigates the clinical course of CCA and subtypes (intrahepatic [iCCA], perihilar [pCCA], and distal [dCCA]) in a pan-European cohort. METHODS: The ENSCCA Registry is a multicenter observational study. Patients were included if they had a histologically proven diagnosis of CCA between 2010-2019. Demographic, histomorphological, biochemical, and clinical studies were performed. RESULTS: Overall, 2,234 patients were enrolled (male/female=1.29). iCCA (n = 1,243) was associated with overweight/obesity and chronic liver diseases involving cirrhosis and/or viral hepatitis; pCCA (n = 592) with primary sclerosing cholangitis; and dCCA (n = 399) with choledocholithiasis. At diagnosis, 42.2% of patients had local disease, 29.4% locally advanced disease (LAD), and 28.4% metastatic disease (MD). Serum CEA and CA19-9 showed low diagnostic sensitivity, but their concomitant elevation was associated with increased risk of presenting with LAD (odds ratio 2.16; 95% CI 1.43-3.27) or MD (odds ratio 5.88; 95% CI 3.69-9.25). Patients undergoing resection (50.3%) had the best outcomes, particularly with negative-resection margin (R0) (median overall survival [mOS] = 45.1 months); however, margin involvement (R1) (hazard ratio 1.92; 95% CI 1.53-2.41; mOS = 24.7 months) and lymph node invasion (hazard ratio 2.13; 95% CI 1.55-2.94; mOS = 23.3 months) compromised prognosis. Among patients with unresectable disease (49.6%), the mOS was 10.6 months for those receiving active palliative therapies, mostly chemotherapy (26.2%), and 4.0 months for those receiving best supportive care (20.6%). iCCAs were associated with worse outcomes than p/dCCAs. ECOG performance status, MD and CA19-9 were independent prognostic factors. CONCLUSION: CCA is frequently diagnosed at an advanced stage, a proportion of patients fail to receive cancer-specific therapies, and prognosis remains dismal. Identification of preventable risk factors and implementation of surveillance in high-risk populations are required to decrease cancer-related mortality. LAY SUMMARY: This is, to date, the largest international (pan-European: 26 hospitals and 11 countries) observational study, in which the course of cholangiocarcinoma has been investigated, comparing the 3 subtypes based on the latest International Classification of Diseases 11th Edition (ICD-11) (i.e., intrahepatic [2C12], perihilar [2C18], or distal [2C15] affected bile ducts), which come into effect in 2022. General and tumor-type specific features at diagnosis, risk factors, biomarker accuracy, as well as patient management and outcomes, are presented and compared, outlining the current clinical state of cholangiocarcinoma in Europe.

PDAC as an Immune Evasive Disease: Can 3D Model Systems Aid to Tackle This Clinical Problem?

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with a high mortality rate. The presence of a dense desmoplastic stroma rich in fibroblasts, extracellular matrix, and immune cells plays a critical role in disease progression, therapy response and is a distinguishing feature of PDAC. PDAC is currently treated with a combination of surgery, chemotherapy and radiation therapy in selected cases which results in long-term survival only in a small percentage of patients. Cancer therapies that incorporate immunotherapy-based techniques have become increasingly common in recent years. While such a strategy has been shown to be effective for immunogenic, "hot" tumors like melanoma and lung cancer, thus far PDAC patients display poor responses to this therapeutic approach. Various factors, such as low tumor mutational burden, increased infiltration of immunosuppressive cells, like MDSCs and Treg cells promote tolerance and immune deviation, further aggravating adaptive immunity in PDAC. In this review we will elaborate on the ability of PDAC tumors to evade immune detection. We will also discuss various 3D model system that can be used as a platform in preclinical research to investigate rational combinations of immunotherapy with chemotherapy or targeted therapy, to prime the immune microenvironment to enhance antitumor activity.

Motixafortide and Pembrolizumab Combined to Nanoliposomal Irinotecan, Fluorouracil, and Folinic Acid in Metastatic Pancreatic Cancer: The COMBAT/KEYNOTE-202 Trial.

PURPOSE: Pancreatic ductal adenocarcinoma (PDAC) is largely unresponsive to checkpoint inhibitors. Blockade of the CXCR4/CXCL12 axis increases intratumoral trafficking of activated T cells while restraining immunosuppressive elements. This study evaluates dual blockade of CXCR4 and PD1 with chemotherapy in PDAC. PATIENTS AND METHODS: Multicenter, single-arm, phase II study to evaluate the safety and efficacy of motixafortide and pembrolizumab combined with chemotherapy in patients with de novo metastatic PDAC and disease progression on front-line gemcitabine-based therapy (NCT02826486). Subjects received a priming phase of motixafortide daily on days 1-5, followed by repeated cycles of motixafortide twice a week; pembrolizumab every 3 weeks; and nanoliposomal irinotecan, fluorouracil, and leucovorin every 2 weeks (NAPOLI-1 regimen). The primary objective was objective response rate (ORR). Secondary objectives included overall survival (OS), progression-free survival (PFS), disease control rate (DCR), safety, and tolerability. RESULTS: A total of 43 patients were enrolled. The ORR according to RECISTv1.1 was 21.1% with confirmed ORR of 13.2%. The DCR was 63.2% with median duration of clinical benefit of 5.7 months. In the intention-to-treat population, median PFS was 3.8 months and median OS was 6.6 months. The triple combination was safe and well tolerated, with toxicity comparable with the NAPOLI-1 regimen. Notably, the incidence of grade 3 or higher neutropenia and infection was 7%, lower than expected for this chemotherapy regimen. CONCLUSIONS: Triple combination of motixafortide, pembrolizumab, and chemotherapy was safe and well tolerated, and showed signs of efficacy in a population with poor prognosis and aggressive disease.

FOSL1 promotes cholangiocarcinoma via transcriptional effectors that could be therapeutically targeted.

BACKGROUND & AIMS: Cholangiocarcinoma (CCA) is a neoplasia of the biliary tract driven by genetic, epigenetic and transcriptional mechanisms. Herein, we investigated the role of the transcription factor FOSL1, as well as its downstream transcriptional effectors, in the development and progression of CCA. METHODS: FOSL1 was investigated in human CCA clinical samples. Genetic inhibition of FOSL1 in human and mouse CCA cell lines was performed in in vitro and in vivo models using constitutive and inducible short-hairpin RNAs. Conditional FOSL1 ablation was done using a genetically engineered mouse (GEM) model of CCA (mutant KRAS and Trp53 knockout). Follow-up RNA and chromatin immunoprecipitation (ChIP) sequencing analyses were carried out and downstream targets were validated using genetic and pharmacological inhibition. RESULTS: An inter-species analysis of FOSL1 in CCA was conducted. First, FOSL1 was found to be highly upregulated in human and mouse CCA, and associated with poor patient survival. Pharmacological inhibition of different signalling pathways in CCA cells converged on the regulation of FOSL1 expression. Functional experiments showed that FOSL1 is required for cell proliferation and cell cycle progression in vitro, and for tumour growth and tumour maintenance in both orthotopic and subcutaneous xenograft models. Likewise, FOSL1 genetic abrogation in a GEM model of CCA extended mouse survival by decreasing the oncogenic potential of transformed cholangiocytes. RNA and ChIP sequencing studies identified direct and indirect transcriptional effectors such as HMGCS1 and AURKA, whose genetic and pharmacological inhibition phenocopied FOSL1 loss. CONCLUSIONS: Our data illustrate the functional and clinical relevance of FOSL1 in CCA and unveil potential targets amenable to pharmacological inhibition that could enable the implementation of novel therapeutic strategies. LAY SUMMARY: Understanding the molecular mechanisms involved in cholangiocarcinoma (bile duct cancer) development and progression stands as a critical step for the development of novel therapies. Through an inter-species approach, this study provides evidence of the clinical and functional role of the transcription factor FOSL1 in cholangiocarcinoma. Moreover, we report that downstream effectors of FOSL1 are susceptible to pharmacological inhibition, thus providing new opportunities for therapeutic intervention.

Paradigms on Immunotherapy Combinations with Chemotherapy.

Checkpoint inhibitors are being added to standard-of-care chemotherapy in multiple clinical trials. Success has been reported in non-small and small cell lung carcinomas and urothelial, head and neck, gastric, and esophageal cancers, and promising results are already available in triple-negative breast and pancreatic malignancies. The potential mechanisms of synergy include immunogenic tumor cell death, antiangiogenesis, selective depletion of myeloid immunosuppressive cells, and lymphopenia, which reduces regulatory T cells and makes room for proliferation of effector T cells. However, chemotherapy regimens have not been optimized for such combinations, perhaps explaining some recent clinical trial disappointments. Approaches to make the most of chemoimmunotherapy include neoadjuvant and adjuvant schemes.Significance: Immunotherapy of cancer based on PD-1/PD-L1 blockade has prompted a revolution in cancer clinical management. Evidence in phase III clinical trials already supports combinations of immunotherapy with standard-of-care chemotherapy for a number of malignant diseases. This review focuses on such evidence and provides an overview of the potential synergistic mechanisms of action and the opportunities to optimize chemoimmunotherapy regimens.

The mutational load and a T-cell inflamed tumour phenotype identify ovarian cancer patients rendering tumour-reactive T cells from PD-1+ tumour-infiltrating lymphocytes.

BACKGROUND: Adoptive immunotherapy with tumour-infiltrating lymphocytes (TIL) may benefit from the use of selective markers, such as PD-1, for tumour-specific T-cell enrichment, and the identification of predictive factors that help identify those patients capable of rendering tumour-reactive TILs. We have investigated this in ovarian cancer (OC) patients as candidates for TIL therapy implementation. METHODS: PD-1- and PD-1+ CD8 TILs were isolated from ovarian tumours and expanded cells were tested against autologous tumour cells. Baseline tumour samples were examined using flow cytometry, multiplexed immunofluorescence and Nanostring technology, for gene expression analyses, as well as a next-generation sequencing gene panel, for tumour mutational burden (TMB) calculation. RESULTS: Tumour-reactive TILs were detected in half of patients and were exclusively present in cells derived from the PD-1+ fraction. Importantly, a high TIL density in the fresh tumour, the presence of CD137+ cells within the PD-1+CD8+ TIL subset and their location in the tumour epithelium, together with a baseline T-cell-inflamed genetic signature and/or a high TMB, are features that identify patients rendering tumour-reactive TIL products. CONCLUSION: We have demonstrated that PD-1 identifies ovarian tumour-specific CD8 TILs and has uncovered predictive factors that identify OC patients who are likely to render tumour-specific cells from PD-1+ TILs.

Intratumoral nanoplexed poly I:C BO-112 in combination with systemic anti-PD-1 for patients with anti-PD-1-refractory tumors.

Intratumoral therapies, especially Toll-like receptor agonists, can trigger both the innate and adaptive immune systems. BO-112 is a nanoplexed form of polyinosinic:polycytidylic acid (poly I:C) that induces local and systemic immunotherapeutic effects in mouse models. In a multicenter phase 1 clinical trial, repeated intratumoral administrations of BO-112 induced an increase in tumor cell necrosis and apoptosis, as well as augmented immune reactivity according to gene expression profiling. The first three cohorts receiving BO-112 as a monotherapy resulted in a recommended dose of 1 mg that could be safely repeated. Two grade 3 to 4 adverse reactions in the form of reversible thrombocytopenia were reported. In a fourth cohort of 28 patients with tumors that had primary resistance to anti-programmed cell death protein-1 (PD-1), the combination of intratumoral BO-112 with nivolumab or pembrolizumab was also well tolerated, and 3 patients (2 with melanoma and 1 with renal cell carcinoma) achieved partial responses, with 10 more patients having stable disease at 8 to 12 weeks. Thus, local BO-112 combined with a systemic anti-PD-1 agent might be a strategy to revert anti-PD-1 resistance.

Endoscopical and pathological dissociation in severe colitis induced by immune-checkpoint inhibitors.

Checkpoint inhibitors have improved the survival of patients with advanced tumors and show a manageable toxicity profile. However, auto-immune colitis remains a relevant side effect, and combinations of anti-PD1/PDL1 and anti-CTLA-4 increase its incidence and severity. Here, we report the case of a 50-year-old patient diagnosed with stage IV cervical cancer that relapsed following radical surgery, external radiation/brachytherapy and standard chemotherapy. She was subsequently treated with Nivolumab and Ipilimumab combination and developed grade 2 colitis presenting a dissociation between endoscopic and pathological findings. At cycle 10 the patient reported grade 3 diarrhea and abdominal discomfort, without blood or mucus in the stools. Immunotherapy was withheld and a colonoscopy was performed, showing normal mucosa in the entire colon. Puzzlingly, histologic evaluation of randomly sampled mucosal biopsy of the distal colon showed an intense intraepithelial lymphocyte infiltration with crypt loss and some regenerating crypts with a few apoptotic bodies set in a chronically inflamed lamina propria, consistent with the microscopic diagnosis of colitis. Treatment with methylprednisolone 2 mg/kg was initiated which led to a decrease in the number of stools to grade 1. Additional investigations to exclude other causes of diarrhea rendered negative results. The patient experienced a major partial response and, following the resolution of diarrhea, she was re-challenged again with immunotherapy, with the reappearance of grade 2 diarrhea, leading to permanent immunotherapy interruption. We conclude and propose that performing random colonic biopsies should be considered in cases of immune checkpoint-associated unexplained diarrhea, even when colonoscopy shows macroscopically normal colonic mucosa inflammatory lesions.

BL-8040, a CXCR4 antagonist, in combination with pembrolizumab and chemotherapy for pancreatic cancer: the COMBAT trial.

Programmed cell death 1 (PD-1) inhibitors have limited effect in pancreatic ductal adenocarcinoma (PDAC), underscoring the need to co-target alternative pathways. CXC chemokine receptor 4 (CXCR4) blockade promotes T cell tumor infiltration and is synergistic with anti-PD-1 therapy in PDAC mouse models. We conducted a phase IIa, open-label, two-cohort study to assess the safety, efficacy and immunobiological effects of the CXCR4 antagonist BL-8040 (motixafortide) with pembrolizumab and chemotherapy in metastatic PDAC (NCT02826486). The primary outcome was objective response rate (ORR). Secondary outcomes were overall survival (OS), disease control rate (DCR) and safety. In cohort 1, 37 patients with chemotherapy-resistant disease received BL-8040 and pembrolizumab. The DCR was 34.5% in the evaluable population (modified intention to treat, mITT; N = 29), including nine patients (31%) with stable disease and one patient (3.4%) with partial response. Median OS (mOS) was 3.3 months in the ITT population. Notably, in patients receiving study drugs as second-line therapy, the mOS was 7.5 months. BL-8040 increased CD8+ effector T cell tumor infiltration, decreased myeloid-derived suppressor cells (MDSCs) and further decreased circulating regulatory T cells. In cohort 2, 22 patients received BL-8040 and pembrolizumab with chemotherapy, with an ORR, DCR and median duration of response of 32%, 77% and 7.8 months, respectively. These data suggest that combined CXCR4 and PD-1 blockade may expand the benefit of chemotherapy in PDAC and warrants confirmation in subsequent randomized trials.

CXCR1 and CXCR2 Chemokine Receptor Agonists Produced by Tumors Induce Neutrophil Extracellular Traps that Interfere with Immune Cytotoxicity.

Neutrophils are expanded and abundant in cancer-bearing hosts. Under the influence of CXCR1 and CXCR2 chemokine receptor agonists and other chemotactic factors produced by tumors, neutrophils, and granulocytic myeloid-derived suppressor cells (MDSCs) from cancer patients extrude their neutrophil extracellular traps (NETs). In our hands, CXCR1 and CXCR2 agonists proved to be the major mediators of cancer-promoted NETosis. NETs wrap and coat tumor cells and shield them from cytotoxicity, as mediated by CD8+ T cells and natural killer (NK) cells, by obstructing contact between immune cells and the surrounding target cells. Tumor cells protected from cytotoxicity by NETs underlie successful cancer metastases in mice and the immunotherapeutic synergy of protein arginine deiminase 4 (PAD4) inhibitors, which curtail NETosis with immune checkpoint inhibitors. Intravital microscopy provides evidence of neutrophil NETs interfering cytolytic cytotoxic T lymphocytes (CTLs) and NK cell contacts with tumor cells.

The Mir181ab1 cluster promotes KRAS-driven oncogenesis and progression in lung and pancreas.

Few therapies are currently available for patients with KRAS-driven cancers, highlighting the need to identify new molecular targets that modulate central downstream effector pathways. Here we found that the microRNA (miRNA) cluster including miR181ab1 is a key modulator of KRAS-driven oncogenesis. Ablation of Mir181ab1 in genetically engineered mouse models of Kras-driven lung and pancreatic cancer was deleterious to tumor initiation and progression. Expression of both resident miRNAs in the Mir181ab1 cluster, miR181a1 and miR181b1, was necessary to rescue the Mir181ab1-loss phenotype, underscoring their nonredundant role. In human cancer cells, depletion of miR181ab1 impaired proliferation and 3D growth, whereas overexpression provided a proliferative advantage. Lastly, we unveiled miR181ab1-regulated genes responsible for this phenotype. These studies identified what we believe to be a previously unknown role for miR181ab1 as a potential therapeutic target in 2 highly aggressive and difficult to treat KRAS-mutated cancers.