Pancreatic ductal adenocarcinoma (PDAC) remains a lethal malignancy with an immunosuppressive microenvironment that is resistant to most therapies. IL17 is involved in pancreatic tumorigenesis, but ...its role in invasive PDAC is undetermined. We hypothesized that IL17 triggers and sustains PDAC immunosuppression. We inhibited IL17/IL17RA signaling using pharmacological and genetic strategies alongside mass cytometry and multiplex immunofluorescence techniques. We uncovered that IL17 recruits neutrophils, triggers neutrophil extracellular traps (NETs), and excludes cytotoxic CD8 T cells from tumors. Additionally, IL17 blockade increases immune checkpoint blockade (PD-1, CTLA4) sensitivity. Inhibition of neutrophils or Padi4-dependent NETosis phenocopies IL17 neutralization. NMR spectroscopy revealed changes in tumor lactate as a potential early biomarker for IL17/PD-1 combination efficacy. Higher expression of IL17 and PADI4 in human PDAC corresponds with poorer prognosis, and the serum of patients with PDAC has higher potential for NETosis. Clinical studies with IL17 and checkpoint blockade represent a novel combinatorial therapy with potential efficacy for this lethal disease.
Circulating miRNAs are known to play important roles in intercellular communication. However, the effects of exosomal miRNAs on cells are not fully understood.
To investigate the role of exosomal ...miR-1246 in ovarian cancer (OC) microenvironment, we performed RPPA as well as many other in vitro functional assays in ovarian cancer cells (sensitive; HeyA8, Skov3ip1, A2780 and chemoresistant; HeyA8-MDR, Skov3-TR, A2780-CP20). Therapeutic effect of miR-1246 inhibitor treatment was tested in OC animal model. We showed the effect of OC exosomal miR-1246 uptake on macrophages by co-culture experiments.
Substantial expression of oncogenic miR-1246 OC exosomes was found. We showed that Cav1 gene, which is the direct target of miR-1246, is involved in the process of exosomal transfer. A significantly worse overall prognosis were found for OC patients with high miR-1246 and low Cav1 expression based on TCGA data. miR-1246 expression were significantly higher in paclitaxel-resistant OC exosomes than in their sensitive counterparts. Overexpression of Cav1 and anti-miR-1246 treatment significantly sensitized OC cells to paclitaxel. We showed that Cav1 and multi drug resistance (MDR) gene is involved in the process of exosomal transfer. Our proteomic approach also revealed that miR-1246 inhibits Cav1 and acts through PDGFβ receptor at the recipient cells to inhibit cell proliferation. miR-1246 inhibitor treatment in combination with chemotherapy led to reduced tumor burden in vivo. Finally, we demonstrated that when OC cells are co-cultured with macrophages, they are capable of transferring their oncogenic miR-1246 to M2-type macrophages, but not M0-type macrophages.
Our results suggest that cancer exosomes may contribute to oncogenesis by manipulating neighboring infiltrating immune cells. This study provide a new mechanistic therapeutic approach to overcome chemoresistance and tumor progression through exosomal miR-1246 in OC patients.
The tumor microbiome (TM) has been linked to pancreatic cancer prognosis. Specific microbes can confer tumor resistance to therapies. Early knowledge of the TM at time of diagnosis would be ...clinically relevant for precision therapy based on microbial composition. However, it is difficult to define the TM prior to surgical resection.
In this pilot feasibility study, patients underwent Endoscopic Ultrasound-Fine Needle Aspiration (EUS-FNA) biopsy of pancreatic adenocarcinoma. These samples were analyzed using 16S rRNA and internal transcribed spacer (ITS) sequencing for characterization of the tumor bacteria and fungi.
After in silico decontamination and comparison to non-matched tumor, we were able to characterize the TM in biopsies, which was comparable to the TM from surgical specimens.
EUS-FNA biopsy may represent a feasible modality to characterize the pancreatic TM prior to surgical resection with proper decontamination strategies and improvements in matched controls.
Recent studies defined a potentially important role of the microbiome in modulating pancreatic ductal adenocarcinoma (PDAC) and responses to therapies. We hypothesized that antibiotic usage may ...predict outcomes in patients with PDAC.
We retrospectively analyzed clinical data of patients with resectable or metastatic PDAC seen at MD Anderson Cancer from 2003 to 2017. Demographic, chemotherapy regimen and antibiotic use, duration, type, and reason for indication were recorded.
A total of 580 patients with PDAC were studied, 342 resected and 238 metastatic patients, selected retrospectively from our database. Antibiotic use, for longer than 48 hrs, was detected in 209 resected patients (61%) and 195 metastatic ones (62%). On resectable patients, we did not find differences in overall survival (OS) or progression‐free survival (PFS), based on antibiotic intake. However, in the metastatic cohort, antibiotic consumption was associated with a significantly longer OS (13.3 months vs. 9.0 months, HR 0.48, 95% CI 0.34–0.7, p = 0.0001) and PFS (4.4 months vs. 2 months, HR 0.48, 95% CI 0.34–0.68, p = <0.0001). In multivariate analysis, the impact of ATB remained significant for PFS (HR 0.59, p = 0.005) and borderline statistically significant for OS (HR 0.69, p = 0.06). When we analyzed by chemotherapy regimen, we found that patients who received gemcitabine‐based chemotherapy as first‐line therapy (n = 118) had significantly prolonged OS (HR 0.4, p 0.0013) and PFS (HR 0.55, p 0.02) if they received antibiotics, while those receiving 5FU‐based chemotherapy (n = 98) had only prolonged PFS (HR 0.54, p = 0.03).
Antibiotics‐associated modulation of the microbiome is associated with better outcomes in patients with metastatic PDAC.
We have analyzed the effect of antibiotics’ intake on two cohorts of patients with pancreatic adenocarcinoma, resectable, and metastatic. We have found that on the metastatic cohort, antibiotics use was significantly associated with better outcomes, particularly, on patients that received gemcitabine based‐chemotherapy as the first line.
Aerobic exercise is associated with decreased cancer incidence and cancer-associated mortality. However, little is known about the effects of exercise on pancreatic ductal adenocarcinoma (PDA), a ...disease for which current therapeutic options are limited. Herein, we show that aerobic exercise reduces PDA tumor growth, by modulating systemic and intra-tumoral immunity. Mechanistically, exercise promotes immune mobilization and accumulation of tumor-infiltrating IL15Rα+ CD8 T cells, which are responsible for the tumor-protective effects. In clinical samples, an exercise-dependent increase of intra-tumoral CD8 T cells is also observed. Underscoring the translational potential of the interleukin (IL)-15/IL-15Rα axis, IL-15 super-agonist (NIZ985) treatment attenuates tumor growth, prolongs survival, and enhances sensitivity to chemotherapy. Finally, exercise or NIZ985 both sensitize pancreatic tumors to αPD-1, with improved anti-tumor and survival benefits. Collectively, our findings highlight the therapeutic potential of an exercise-oncology axis and identify IL-15 activation as a promising treatment strategy for this deadly disease.
Display omitted
•Aerobic exercise restricts pancreatic tumor growth by enhancing anti-tumor immunity•The anti-tumor effects of aerobic exercise are driven by IL-15Rα+ CD8 T cells•Pharmacological activation of IL-15/IL-15Rα promotes a durable anti-tumor response•Aerobic exercise and IL-15 activation sensitize pancreatic tumors to α-PD-1 therapy
Kurz. et al. discover that aerobic exercise slows pancreatic cancer growth in mice through activation of the immune system, particularly CD8+ T cells. The beneficial effects of exercise can be mimicked by treatment with an IL-15 super-agonist, NIZ985. Exercise or NIZ985 both improve the responsiveness of murine pancreatic tumors to immune- and non-immune- based therapeutics.
691
Background: Pancreatic cancer (PC) is the third leading cause of cancer death in the United States. The high mortality associated with PC is attributed to multiple reasons: lack of effective ...therapies, aggressive biology and late diagnosis. Due to the absence of reliable early disease biomarkers, PC screening is largely dependent on imaging. Recent studies have highlighted the importance of the gut and tumor microbiome in PC. We present here the first report of oral and gut microbiome prospective analysis of PC high-risk individuals (PC-HRI) undergoing screening. Methods: We collected periodontal and stool samples at the University of Texas MD Anderson Cancer Center from 2017-2022. A total of 448 samples, consisting of 250 oral and 198 gut samples were obtained. Samples were collected from PC (n=73), PC-HRI (n=34), and healthy (n=143) individuals. 16s rRNA sequencing was used to characterize the oral and gut microbiome and statistical analysis and correlation with imaging and clinical characteristics were performed. Results: We identified three phyla, namely Proteobacteria, Actinobacteria, and Fusobacteria as significantly more abundant in the gut microbiome of PC patients. Conversely, Proteobacteria was decreased in the oral microbiome of PC patients. At the class level, Gammaproteobacteria (GP) oral/gut ratio was significantly decreased in PC patients compared with healthy individuals (p=0.02). Analysis of PC-HRI revealed also low GP oral/gut ratio in high-risk individuals who were diagnosed with worrisome pancreatic focal lesions. Interestingly, Gammaproteobacteria (GP) is one of the main classes of bacteria detected in pancreatic cancer tissue. GP shifts in oral and gut environments could be implicated in pancreatic early tumorigenesis and serve as biomarker of the disease. Additionally, gut bacteria with metabolic pathways related to lipid metabolism were more enriched in PC patients and PC-HRI with focal lesions compared to healthy controls. Conclusions: Gammaproteobacteria oral/gut ratio represents a potential novel biomarker which could predict presence of early high risk-pancreatic focal lesions in PC-HRI. Taken together, this report provides observational evidence about changes in oral and gut microbiome in patients with pancreatic cancer but even more importantly, the fact that those changes could be detected in PC-HRI with early high-risk lesions. Broader validation in other high-risk cohorts would be required. Detection of GP oral/gut ratio would represent an inexpensive, non-invasive method that could be useful for PC screening. Functional studies should be performed to determine how GP shifts can contribute with pancreatic tumorigenesis. Research supported by CPRIT (Grant Number: RP200173) and philanthropic funding through the MD Anderson Moonshot Program.
4135
Background: About 10% of pancreatic neuroendocrine tumors (pNETs) are thought to be related to inherited syndromes, including multiple endocrine neoplasia type 1 (MEN1), multiple endocrine ...neoplasia type 4 (MEN4), von Hippel-Lindau disease (VHL), neurofibromatosis type 1 (NF1), and tuberous sclerosis complex (TSC). Here, we report the prevalence of pathological/likely pathological germline variants (PV/LPV) in 2 cohorts: 1) High-risk and 2) Unselected. Methods: We retrospectively collected clinical data of patients with biopsy proven pNETs seen at MD Anderson Cancer Center (MDACC) and Johns Hopkins Hospital (JHH). Cohort 1 (high risk cohort) included 132 patients seen at MDACC, who underwent germline testing based on high-risk criteria such as early onset, personal or family history of cancer and syndromic features between 2013 -2019. Cohort 2 (unselected cohort) included 106 patients seen at JHH, who underwent germline testing following their diagnosis of pNETs between 2020 to 2022. Results: In the high-risk cohort (n = 132), 33% (n = 44) had PV/LPV, and 17 % (n = 22) had a variant of unknown significance (VUS). Amongst the 132 patients, 35% underwent multigene panel testing, 53% had targeted germline testing and 12% had a physician documented outside test diagnosis. The demographics consisted of 52%(n = 69) females, 67% (n = 88) white, 54%(n = 71) had metastatic disease, 58%(n = 76) underwent surgical resection. WHO grading (n = 77) is as follows G1 (39%), G2 (59%), G3 (2%). In the unselected cohort (n = 106), 21% (n = 22) had PV/LPV, 28 % (n = 30) had a VUS. Of these, 93% of the patients underwent multigene panel testing. The demographics consisted of 42% (n = 44) females, 67% (n = 88) white, 48% (n = 51) had metastatic disease, 60% (n = 64) underwent surgical resection, WHO grading (n = 93) is as follows G1 (37%), G2 (49%), G3 (14%). Conclusions: PV/LPV are prevalent in patients with sporadic pNET irrespective of high-risk features or family history. While in the high-risk patients there is a higher prevalence, we also identified a 21% prevalence of PV/LPV with universal germline testing in the unselected cohort. In both cohorts, we identified a high number of mutations in the DNA repair pathway not previously described, which could affect subsequent therapies and surveillance for patients and their family members. The findings support upfront universal germline testing in all patients with diagnosis of pNETs. Table: see text
Microbes influence cancer initiation, progression and therapy responsiveness. IL-17 signaling contributes to gut barrier immunity by regulating microbes but also drives tumor growth. A knowledge gap ...remains regarding the influence of enteric IL-17-IL-17RA signaling and their microbial regulation on the behavior of distant tumors. We demonstrate that gut dysbiosis induced by systemic or gut epithelial deletion of IL-17RA induces growth of pancreatic and brain tumors due to excessive development of Th17, primary source of IL-17 in human and mouse pancreatic ductal adenocarcinoma, as well as B cells that circulate to distant tumors. Microbial dependent IL-17 signaling increases DUOX2 signaling in tumor cells. Inefficacy of pharmacological inhibition of IL-17RA is overcome with targeted microbial ablation that blocks the compensatory loop. These findings demonstrate the complexities of IL-17-IL-17RA signaling in different compartments and the relevance for accounting for its homeostatic host defense function during cancer therapy.
Display omitted
•Gut dysbiosis triggered by enteric IL-17RA deficiency induces remote tumor growth•Inefficient gut IL-17 signaling triggers tumor promoting Th17 and B cells•IL-17 inhibition with concurrent microbial depletion exerts anti-tumoral efficacy•IL-17 expression is associated with DUOX2, primary target of IL-17, in human PDAC
Chandra et al. reveal a mechanism of resistance to cytokine inhibition in cancer that is dependent on intestinal IL-17-IL-17RA signaling mediated microbial regulation. Gut dysbiosis triggered by disruption of enteric epithelial IL-17RA signaling promotes growth of remote tumors through systemic immunomodulation.