Influence of microbiota-associated metabolic reprogramming on clinical outcome in patients with melanoma from the randomized adjuvant dendritic cell-based MIND-DC trial

Tumor immunosurveillance plays a major role in melanoma, prompting the development of immunotherapy strategies. The gut microbiota composition, influencing peripheral and tumoral immune tonus, earned its credentials among predictors of survival in melanoma. The MIND-DC phase III trial (NCT02993315) randomized (2:1 ratio) 148 patients with stage IIIB/C melanoma to adjuvant treatment with autologous natural dendritic cell (nDC) or placebo (PL). Overall, 144 patients collected serum and stool samples before and after 2 bimonthly injections to perform metabolomics (MB) and metagenomics (MG) as prespecified exploratory analysis. Clinical outcomes are reported separately. Here we show that different microbes were associated with prognosis, with the health-related Faecalibacterium prausnitzii standing out as the main beneficial taxon for no recurrence at 2 years (p = 0.008 at baseline, nDC arm). Therapy coincided with major MB perturbations (acylcarnitines, carboxylic and fatty acids). Despite randomization, nDC arm exhibited MG and MB bias at baseline: relative under-representation of F. prausnitzii, and perturbations of primary biliary acids (BA). F. prausnitzii anticorrelated with BA, medium- and long-chain acylcarnitines. Combined, these MG and MB biomarkers markedly determined prognosis. Altogether, the host-microbial interaction may play a role in localized melanoma. We value systematic MG and MB profiling in randomized trials to avoid baseline differences attributed to host-microbe interactions.

A microbiota-modulated checkpoint directs immunosuppressive intestinal T cells into cancers

Antibiotics (ABX) compromise the efficacy of programmed cell death protein 1 (PD-1) blockade in cancer patients, but the mechanisms underlying their immunosuppressive effects remain unknown. By inducing the down-regulation of mucosal addressin cell adhesion molecule 1 (MAdCAM-1) in the ileum, post-ABX gut recolonization by Enterocloster species drove the emigration of enterotropic α4β7+CD4+ regulatory T 17 cells into the tumor. These deleterious ABX effects were mimicked by oral gavage of Enterocloster species, by genetic deficiency, or by antibody-mediated neutralization of MAdCAM-1 and its receptor, α4β7 integrin. By contrast, fecal microbiota transplantation or interleukin-17A neutralization prevented ABX-induced immunosuppression. In independent lung, kidney, and bladder cancer patient cohorts, low serum levels of soluble MAdCAM-1 had a negative prognostic impact. Thus, the MAdCAM-1-α4β7 axis constitutes an actionable gut immune checkpoint in cancer immunosurveillance.

Impact of microbiota on breast cancer hormone therapy

Recent observations indicate that the pathogenesis and prognosis of hormone-receptor breast cancer is not only dictated by the properties of the malignant cells but also by immune and microbial parameters. Thus, the immunosurveillance system retards the development of hormone-positive breast cancer and contributes to the therapeutic efficacy of estrogen receptor antagonists and aromatase inhibitors. Moreover, the anticancer immune response is profoundly modulated by the local and intestinal microbiota, which influences cancer cell-intrinsic signaling pathways, affects the composition and function of the immune infiltrate present in the tumor microenvironment and modulates the metabolism of estrogens. Indeed, specific bacteria in the gut produce enzymes that affect the enterohepatic cycle of estrogen metabolites, convert estrogens into androgens or generate estrogen-like molecules. The knowledge of these circuitries is in its infancy, calling for further in-depth analyses.

RET-MAP: An International Multicenter Study on Clinicobiologic Features and Treatment Response in Patients With Lung Cancer Harboring a RET Fusion

INTRODUCTION

Nearly 1% to 2% of NSCLCs harbor RET fusions. Characterization of this rare population is still incomplete.

METHODS

This retrospective multicenter study included patients with any-stage RET positive (RET+) NSCLC from 31 cancer centers. Molecular profiling included DNA/RNA sequencing or fluorescence in situ hybridization analyses. Clinicobiological features and treatment outcomes (per investigator) with surgery, chemotherapy (CT), immune checkpoint blockers (ICBs), CT-ICB, multityrosine kinase inhibitors, and RET inhibitors (RETis) were evaluated.

RESULTS

For 218 patients included between February 2012 and April 2022, median age was 63 years, 56% were females, 93% had adenocarcinoma, and 41% were smokers. The most frequent fusion partner was KIF5B (72%). Median tumor mutational burden was 2.5 (range: 1-4) mutations per megabase, and median programmed death-ligand 1 expression was 10% (range: 0%-55%). The most common metastatic sites were the lung (50%), bone (43%), and pleura (40%). Central nervous system metastases were found at diagnosis of advanced NSCLC in 21% of the patients and at last follow-up or death in 31%. Overall response rate and median progression-free survival were 55% and 8.7 months with platinum doublet, 26% and 3.6 months with single-agent CT, 46% and 9.6 months with CT-ICB, 23% and 3.1 months with ICB, 37% and 3 months with multityrosine kinase inhibitor, and 76% and 16.2 months with RETi, respectively. Median overall survival was longer in patients treated with RETi versus no RETi (50.6 mo [37.7-72.1] versus 16.3 mo [12.7-28.8], p < 0.0001).

CONCLUSIONS

Patients with RET+ NSCLC have mainly thoracic and bone disease and low tumor mutational burden and programmed death-ligand 1 expression. RETi markedly improved survival, whereas ICB may be active in selected patients.

Effects of the intestinal microbiota on prostate cancer treatment by androgen deprivation therapy

Prostate cancer (PC) can be kept in check by androgen deprivation therapy (ADT, usually with the androgen synthesis inhibitor abiraterone acetate or the androgen receptor antagonist such as enzalutamide) until the tumor evolves to castration-resistant prostate cancer (CRPC). The transition of hormone-sensitive PC (HSPC) to CPRC has been explained by cancer cell-intrinsic resistance mechanisms. Recent data indicate that this transition is also marked by cancer cell-extrinsic mechanisms such as the failure of ADT-induced PC immunosurveillance, which depends on the presence of immunostimulatory bacteria in the gut. Moreover, intestinal bacteria that degrade drugs used for ADT, as well as bacteria that produce androgens, can interfere with the efficacy of ADT. Thus, specific bacteria in the gut serve as a source of testosterone, which accelerates prostate cancer progression, and men with CRPC exhibit an increased abundance of such bacteria with androgenic functions. In conclusion, the response of PC to ADT is profoundly influenced by the composition of the microbiota with its immunostimulatory, immunosuppressive and directly ADT-subversive elements.

Abstract 4019: RET-MAP: An international multi-center study of patients with advanced non-small cell lung cancer and RET fusions

Introduction: RET fusions (RET+) are identified in nearly 1% of advanced NSCLC (aNSCLC). We evaluated characteristics and outcomes of patients (pts) with RET+ aNSCLC.

Methods: This is an international, multicenter, retrospective study evaluating clinical, biological, pathological and radiological data of pts with RET+ aNSCLC. Objective response rates (ORR), duration of response (DOR) and progression-free survival (PFS) were evaluated under double or single agent chemotherapy (CT), immunotherapy (ICI), CT-ICI, multityrosine kinase inhibitors (MTKi) and RET inhibitors (RETi). Overall survival (OS) was calculated from the start of first line therapy and compared between pts treated or not by RETi, after stratification by number of treatment lines.

Results: A total of 71 pts was included from 11 centers. Median age was 60 [IQR 47-69], 58% were female, 93% had adenocarcinoma, 2 pts (3%) had squamous and 2 (3%) neuroendocrine carcinoma, 38 (53.5%) were tobacco consumers (median 18.5 PY [7.8-31.3]), 50 (70%) had stage IV disease at diagnosis. Fusion partners were KIF5B (35/49, 71%), CCDC6 (9/49, 18%), others (5/49, 10%). Median TMB was 2.76 [2.0-8.5], median PD-L1 5% [0-29]. The most frequent co-mutation was TP53 (18/58 cases, 31%). Median number of metastatic sites was 2 [1-3], most commonly lung (48%), bone (45%), pleura (41%) and nodes (35%). Brain metastases were found in 18% of cases at diagnosis and in 31% at last follow-up or death. Table reports outcomes by treatment. mOS was 50.6 months [95%CI 37.6 - NR]. Fifty-two pts received 1st generation RETi. The use of RETi improved OS in pts treated with ≤2 lines of therapy (NR vs 17.8 months, p=0.024) and in those receiving &gt;2 lines (50.6 vs 12.7 months, p=0.0037). Pts responding to ICI had a median PD-L1 of 85% [15.5-90].

Conclusions: Pts with RET+ aNSCLC have mainly thoracic and bone disease. Despite smoking history, median TMB and PD-L1 expression are low. ICI may have a significant activity in selected cases. RETi improve OS.

Outcomes by treatment First use of Doublet CT (N=46) Single agent CT (N=12) CT-ICI (N=9) ICI (N=19) MTKi (N=9) RETi (N=52) Line of treatment (median, range) 1 [1-1] 2 [2-3] 1 [1-2] 2 [2-3] 3 [1.5-3.5] 2 [1-3] ORR (N,%) 25/40 (62.5%) 3/12 (25%) 3/9 (33%) 7/17 (41%) 4/8 (50%) 36/45 (80%) mPFS (months, 95%CI) 7.89 [6.18-14] 2.81 [2.43-NR] 5.62 [2.79-NR] 3.71 [2.99-11.5] 2.76 [1.51-NR] 24.7 [16.2-NR] mDOR (months,95%CI) 11.83 [7.06-15.6] 8.90 [4.21-NR] 14.47 [10.25-NR] 20.47 [11.3-NR] 8.18 [1.64-NR] 24.74 [17.12-NR] Stopped for toxicity (N,%) 7/46 (15%) 1/12 (8%) 2/9 (22%) 4/18 (22%) 1/9 (11%) 14/50 (28%)

Citation Format: Mihaela Aldea, Arianna Marinello, Wael Zrafi, Fabrizio Tabbo, Florian Guisier, Damien Vasseur, Vincent Fallet, Clarisse Audigier-Valette, Laura Mezquita, Antonio Calles, Giannis Mountzios, Marco Tagliamento, Judith Raimbourg, Safae Terrisse, Silvia Novello, Maria-Rosa Ghigna, Fabrice Barlesi, David Planchard, Benjamin Besse. RET-MAP: An international multi-center study of patients with advanced non-small cell lung cancer and RET fusions [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4019.

The Polarity and Specificity of Antiviral T Lymphocyte Responses Determine Susceptibility to SARS-CoV-2 Infection in Patients with Cancer and Healthy Individuals

Vaccination against coronavirus disease 2019 (COVID-19) relies on the in-depth understanding of protective immune responses to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). We characterized the polarity and specificity of memory T cells directed against SARS-CoV-2 viral lysates and peptides to determine correlates with spontaneous, virus-elicited, or vaccine-induced protection against COVID-19 in disease-free and cancer-bearing individuals. A disbalance between type 1 and 2 cytokine release was associated with high susceptibility to COVID-19. Individuals susceptible to infection exhibited a specific deficit in the T helper 1/T cytotoxic 1 (Th1/Tc1) peptide repertoire affecting the receptor binding domain of the spike protein (S1-RBD), a hotspot of viral mutations. Current vaccines triggered Th1/Tc1 responses in only a fraction of all subject categories, more effectively against the original sequence of S1-RBD than that from viral variants. We speculate that the next generation of vaccines should elicit Th1/Tc1 T-cell responses against the S1-RBD domain of emerging viral variants.

SIGNIFICANCE

This study prospectively analyzed virus-specific T-cell correlates of protection against COVID-19 in healthy and cancer-bearing individuals. A disbalance between Th1/Th2 recall responses conferred susceptibility to COVID-19 in both populations, coinciding with selective defects in Th1 recognition of the receptor binding domain of spike. See related commentary by McGary and Vardhana, p. 892. This article is highlighted in the In This Issue feature, p. 873.

Immune system and intestinal microbiota determine efficacy of androgen deprivation therapy against prostate cancer

Background

Prostate cancer (PC) responds to androgen deprivation therapy (ADT) usually in a transient fashion, progressing from hormone-sensitive PC (HSPC) to castration-resistant PC (CRPC). We investigated a mouse model of PC as well as specimens from PC patients to unravel an unsuspected contribution of thymus-derived T lymphocytes and the intestinal microbiota in the efficacy of ADT.

Methods

Preclinical experiments were performed in PC-bearing mice, immunocompetent or immunodeficient. In parallel, we prospectively included 65 HSPC and CRPC patients (Oncobiotic trial) to analyze their feces and blood specimens.

Results

In PC-bearing mice, ADT increased thymic cellularity and output. PC implanted in T lymphocyte-depleted or athymic mice responded less efficiently to ADT than in immunocompetent mice. Moreover, depletion of the intestinal microbiota by oral antibiotics reduced the efficacy of ADT. PC reduced the relative abundance of Akkermansia muciniphila in the gut, and this effect was reversed by ADT. Moreover, cohousing of PC-bearing mice with tumor-free mice or oral gavage with Akkermansia improved the efficacy of ADT. This appears to be applicable to PC patients because long-term ADT resulted in an increase of thymic output, as demonstrated by an increase in circulating recent thymic emigrant cells (sjTRECs). Moreover, as compared with HSPC controls, CRPC patients demonstrated a shift in their intestinal microbiota that significantly correlated with sjTRECs. While feces from healthy volunteers restored ADT efficacy, feces from PC patients failed to do so.

Conclusions

These findings suggest the potential clinical utility of reversing intestinal dysbiosis and repairing acquired immune defects in PC patients.

Immune system and intestinal microbiota determine efficacy of androgen depletion therapy against prostate cancer

168

Background: Prostate cancer (PC) responds to androgen deprivation therapy (ADT) usually in a transient fashion, progressing from hormone-sensitive PC (HSPC) to castration-resistant PC (CRPC). While it is recognized that ADT has an immunomodulatory effect, little is known about the intestinal microbiome effect on therapeutic outcome of ADT. Methods: We investigated a mouse model of PC as well as specimens from PC patients to unravel an unsuspected contribution of thymus-derived T lymphocytes and the intestinal microbiota in the efficacy of ADT. Preclinical experiments were performed in PC-bearing mice, immunocompetent or immunodeficient. In parallel, we prospectively included 65 HSPC and CRPC patients to analyze their feces and blood specimen. Results: In PC-bearing mice, ADT increased thymic cellularity and output. PC implanted in T lymphocyte-depleted or athymic mice responded less efficiently to ADT than in immunocompetent mice. Moreover, depletion of the intestinal microbiota by oral antibiotics reduced the efficacy of ADT. PC reduced the relative abundance of Akkermansia muciniphila in the gut, and this effect was reversed by ADT. Moreover, cohousing of PC-bearing mice with tumor-free mice, or oral gavage with Akkermansia improved the efficacy of ADT. This appear to be applicable to PC patients because long-term ADT resulted in an increase of thymic output, as demonstrated by an increase in circulating recent thymic emigrant cells (sjTRECs). Moreover, as compared to HSPC controls, CRPC patients demonstrated a shift in their intestinal microbiota that significantly correlated with sjTRECs. While feces from healthy volunteers restored ADT efficacy. Conclusions: These findings suggest that reversing the intestinal dysbiosis and repairing acquired immune defects in PC patients have a potential impact on the therapeutic outcome of ADT.

Intestinal Akkermansia muciniphila predicts clinical response to PD-1 blockade in patients with advanced non-small-cell lung cancer

Aside from PD-L1 expression, biomarkers of response to immune checkpoint inhibitors (ICIs) in non-small-cell lung cancer (NSCLC) are needed. In a previous retrospective analysis, we documented that fecal Akkermansia muciniphila (Akk) was associated with clinical benefit of ICI in patients with NSCLC or kidney cancer. In the current study, we performed shotgun-metagenomics-based microbiome profiling in a large cohort of patients with advanced NSCLC (n = 338) treated with first- or second-line ICIs to prospectively validate the predictive value of fecal Akk. Baseline stool Akk was associated with increased objective response rates and overall survival in multivariate analyses, independent of PD-L1 expression, antibiotics, and performance status. Intestinal Akk was accompanied by a richer commensalism, including Eubacterium hallii and Bifidobacterium adolescentis, and a more inflamed tumor microenvironment in a subset of patients. However, antibiotic use (20% of cases) coincided with a relative dominance of Akk above 4.8% accompanied with the genus Clostridium, both associated with resistance to ICI. Our study shows significant differences in relative abundance of Akk that may represent potential biomarkers to refine patient stratification in future studies.

Prolonged SARS-CoV-2 RNA virus shedding and lymphopenia are hallmarks of COVID-19 in cancer patients with poor prognosis

Patients with cancer are at higher risk of severe coronavirus infectious disease 2019 (COVID-19), but the mechanisms underlying virus-host interactions during cancer therapies remain elusive. When comparing nasopharyngeal swabs from cancer and noncancer patients for RT-qPCR cycle thresholds measuring acute respiratory syndrome coronavirus-2 (SARS-CoV-2) in 1063 patients (58% with cancer), we found that malignant disease favors the magnitude and duration of viral RNA shedding concomitant with prolonged serum elevations of type 1 IFN that anticorrelated with anti-RBD IgG antibodies. Cancer patients with a prolonged SARS-CoV-2 RNA detection exhibited the typical immunopathology of severe COVID-19 at the early phase of infection including circulation of immature neutrophils, depletion of nonconventional monocytes, and a general lymphopenia that, however, was accompanied by a rise in plasmablasts, activated follicular T-helper cells, and non-naive Granzyme B+FasL+, EomeshighTCF-1high, PD-1+CD8+ Tc1 cells. Virus-induced lymphopenia worsened cancer-associated lymphocyte loss, and low lymphocyte counts correlated with chronic SARS-CoV-2 RNA shedding, COVID-19 severity, and a higher risk of cancer-related death in the first and second surge of the pandemic. Lymphocyte loss correlated with significant changes in metabolites from the polyamine and biliary salt pathways as well as increased blood DNA from Enterobacteriaceae and Micrococcaceae gut family members in long-term viral carriers. We surmise that cancer therapies may exacerbate the paradoxical association between lymphopenia and COVID-19-related immunopathology, and that the prevention of COVID-19-induced lymphocyte loss may reduce cancer-associated death.

Intestinal microbiota influences clinical outcome and side effects of early breast cancer treatment

The prognosis of early breast cancer (BC) relies on cell autonomous and immune parameters. The impact of the intestinal microbiome on clinical outcome has not yet been evaluated. Shotgun metagenomics was used to determine the composition of the fecal microbiota in 121 specimens from 76 early BC patients, 45 of whom were paired before and after chemotherapy. These patients were enrolled in the CANTO prospective study designed to record the side effects associated with the clinical management of BC. We analyzed associations between baseline or post-chemotherapy fecal microbiota and plasma metabolomics with BC prognosis, as well as with therapy-induced side effects. We examined the clinical relevance of these findings in immunocompetent mice colonized with BC patient microbiota that were subsequently challenged with histo-compatible mouse BC and chemotherapy. We conclude that specific gut commensals that are overabundant in BC patients compared with healthy individuals negatively impact BC prognosis, are modulated by chemotherapy, and may influence weight gain and neurological side effects of BC therapies. These findings obtained in adjuvant and neoadjuvant settings warrant prospective validation.

Microbiota-Centered Interventions: The Next Breakthrough in Immuno-Oncology?

The cancer-immune dialogue subject to immuno-oncological intervention is profoundly influenced by microenvironmental factors. Indeed, the mucosal microbiota-and more specifically, the intestinal ecosystem-influences the tone of anticancer immune responses and the clinical benefit of immunotherapy. Antibiotics blunt the efficacy of immune checkpoint inhibitors (ICI), and fecal microbial transplantation may restore responsiveness of ICI-resistant melanoma. Here, we review the yin and yang of intestinal bacteria at the crossroads between the intestinal barrier, metabolism, and local or systemic immune responses during anticancer therapies. We discuss diagnostic tools to identify gut dysbiosis and the future prospects of microbiota-based therapeutic interventions. SIGNIFICANCE: Given the recent proof of concept of the potential efficacy of fecal microbial transplantation in patients with melanoma primarily resistant to PD-1 blockade, it is timely to discuss how and why antibiotics compromise the efficacy of cancer immunotherapy, describe the balance between beneficial and harmful microbial species in play during therapies, and introduce the potential for microbiota-centered interventions for the future of immuno-oncology.

Survival of Patients with Epidermal Growth Factor Receptor-Mutated Metastatic Non-Small Cell Lung Cancer Treated beyond the Second Line in the Tyrosine Kinase Inhibitor Era

Simple Summary

The identification of activating mutations in specific genes in non-small cell lung cancer (NSCLC) has led to the development of targeted therapies, which are currently part of the algorithm for their management. The recommendations agree on first and second-line metastatic treatments in Epidermal Growth Factor Receptor (EGFR) mutations patients. The aim of our retrospective, longitudinal and analytic study was to analyze the survival of EGFR-mutated patients treated beyond the second line of treatment. We confirmed in a population of 31 patients which received at least three lines of treatment that the Progression Free Survival (PFS) was best if we used chemotherapy in second-line and tyrosine kinase inhibitors (TKI) in third-line. We found no difference in Overall Survival (OS) according to the pattern of treatments. In practice, in the TKI era, chemotherapy can still be used in second-line or third-line of treatment.

Abstract

Background: The identification of activating mutations in specific genes led to the development of targeted therapies for NSCLC. TKI directed against EGFR-mutations were the first to prove their major efficacy. Medical associations recommend their use as first and second-line metastatic treatments in EGFR-mutated patients. Our objective was to analyze the survival of EGFR-mutated patients treated beyond the second line of treatment. Methods: We performed a longitudinal, retrospective and analytical study at APHP (Assistance Publique Hopitaux de Paris) Saint Louis, Paris, France, from 1 January 2010 to 31 December 2020 (11 years), on EGFR-mutated patients with metastatic NSCLC which received TKI or chemotherapy (CT) in third-line. Results: Out of about 107 EGFR-mutated patients, 31 patients who benefited from TKI or CT in the third line of treatment were retained for this study. The mean age was 60.03 ± 11.93 years and the sex ratio male/female was 0.24. Mutations of exon 19, 21 and 20 were found in 21 (67.7%), 7 (22.6%) and 7 (22.6%) patients, respectively. Third-line treatment was CT for 16 patients (51.6%) and TKI for the 15 remaining patients (48.4%). Osimertinib was the most used TKI in third-line (n = 10/15; 66.67%). The median duration of third-line treatment was 5.37 months (range 0.53–37.6) and the median follow-up duration was 40.83 months (range 11.33–88.57). There was a significant difference in PFS between patients treated with TKI and CT in third-line (p = 0.028). For patients treated with CT in second-line, there was a significant difference of PFS (p < 0.001) and OS (p = 0.014) in favor of the use of TKI in third-line. Conclusions: For patients receiving CT in second-line, TKI appears to be a better alternative in third-line compared to CT. Osimertinib may be used in third line treatment if not used before.

Effects of acyl-coenzyme A binding protein (ACBP)/diazepam-binding inhibitor (DBI) on body mass index

In mice, the plasma concentrations of the appetite-stimulatory and autophagy-inhibitory factor acyl-coenzyme A binding protein (ACBP, also called diazepam-binding inhibitor, DBI) acutely increase in response to starvation, but also do so upon chronic overnutrition leading to obesity. Here, we show that knockout of Acbp/Dbi in adipose tissue is sufficient to prevent high-fat diet-induced weight gain in mice. We investigated ACBP/DBI plasma concentrations in several patient cohorts to discover a similar dual pattern of regulation. In relatively healthy subjects, ACBP/DBI concentrations independently correlated with body mass index (BMI) and age. The association between ACBP/DBI and BMI was lost in subjects that underwent major weight gain in the subsequent 3-9 years, as well as in advanced cancer patients. Voluntary fasting, undernutrition in the context of advanced cancer, as well as chemotherapy were associated with an increase in circulating ACBP/DBI levels. Altogether, these results support the conclusion that ACBP/DBI may play an important role in body mass homeostasis as well as in its failure.

Immunodynamics of explanted human tumors for immuno-oncology

Decision making in immuno‐oncology is pivotal to adapt therapy to the tumor microenvironment (TME) of the patient among the numerous options of monoclonal antibodies or small molecules. Predicting the best combinatorial regimen remains an unmet medical need. Here, we report a multiplex functional and dynamic immuno‐assay based on the capacity of the TME to respond to ex vivo stimulation with twelve immunomodulators including immune checkpoint inhibitors (ICI) in 43 human primary tumors. This "in sitro" (in situ/in vitro) assay has the potential to predict unresponsiveness to anti‐PD‐1 mAbs, and to detect the most appropriate and personalized combinatorial regimen. Prospective clinical trials are awaited to validate this in sitro assay.

Overall Survival in Men With Bone Metastases From Castration-Resistant Prostate Cancer Treated With Bone-Targeting Radioisotopes: A Meta-analysis of Individual Patient Data From Randomized Clinical Trials

Importance

Both α-emitting and β-emitting bone-targeted radioisotopes (RIs) have been developed to treat men with metastatic castration-resistant prostate cancer (CRPC). Only 1 phase 3 randomized clinical trial has demonstrated an overall survival (OS) benefit from an α-emitting RI, radium 223 (223Ra), vs standard of care. Yet no head-to-head comparison has been done between α-emitting and β-emitting RIs.

Objective

To assess OS in men with bone metastases from CRPC treated with bone-targeted RIs and to compare the effects of α-emitting RIs with β-emitting RIs.

Data Sources

PubMed, Cochrane Library, ClinicalTrials.gov, and meeting proceedings between January 1993 and June 2013 were reviewed. Key terms included randomized trials, radioisotopes, radiopharmaceuticals, and prostate cancer. Data were collected, checked, and analyzed from February 2017 to October 2018.

Study Selection

Selected trials included patients with prostate cancer, recruited more than 50 patients from January 1993 to June 2013, compared RI use with no RI use (placebo, external radiotherapy, or chemotherapy), and were randomized. Patients were diagnosed with histologically proven prostate cancer and disease progression after both surgical or chemical castration and have evidence of bone metastasis. Nine randomized clinical trials were identified as eligible, but 3 were excluded for insufficient data.

Data Extraction and Synthesis

Individual patient data were requested for each eligible trial, and all data were checked with a standard procedure. The log-rank test stratified by trial was used to estimate hazard ratios (HRs), and a similar fixed-effects (FE) model was used to estimate odds ratios (ORs). The between-trial heterogeneity of treatment effects was evaluated by Cochran test and I2 and was accounted by a random-effects (RE) model.

Main Outcomes and Measures

Overall survival; secondary outcomes were symptomatic skeletal event (SSE)-free survival and adverse events.

Results

Based on 6 randomized clinical trials including 2081 patients, RI use was significantly associated with OS compared with no RI use (HR, 0.86; 95% CI, 0.77-0.95; P = .004) with high heterogeneity (χ25 = 24.46; P < .001; I2 = 80%), but this association disappeared when using an RE model (HR, 0.80; 95% CI, 0.61-1.06; P = .12; τ2 = 0.08). The heterogeneity is explained both by the type of RI and by the inclusion of 2 outlier trials that included 275 patients; the OS benefit was significantly higher with the α-emitting RI 223Ra (HR, 0.70; 95% CI, 0.58-0.83) but not significant with the β-emitting RI strontium-89 (HR, 0.96; 95% CI, 0.84-1.10) (P for interaction = .004). Excluding the outlier trials led to an overall HR of 0.82 (95% CI, 0.73-0.92; P < .001) (between-trial heterogeneity: χ23 = 6.51; P = .09; I2 = 54%) using an FE model and an HR of 0.80 (95% CI, 0.65-0.99; P = .04; τ2 = 0.02) using an RE model. The HR for SSE-free survival was 0.81 (95% CI, 0.69-0.93; P = .004) (between-trial heterogeneity: χ23 = 6.71; P = .08; I2 = 55%) when using an FE model and was 0.76 (95% CI, 0.58-1.01; P = .06; τ2 = 0.04) when using an RE model. There were more hematological toxic effects with RI use compared with no RI use (OR, 1.48; 95% CI, 1.17-1.88; P = .001).

Conclusions and Relevance

In metastatic CRPC, a significant improvement of OS and SSE-free survival was obtained with bone-targeted α-emitting but not β-emitting RIs. Caution is necessary for generalizability of these results, given the between-trial heterogeneity.

The Gut Microbiome Associates with Immune Checkpoint Inhibition Outcomes in Patients with Advanced Non-Small Cell Lung Cancer

The gut microbiome (GM) plays an important role in shaping systemic immune responses and influences immune checkpoint inhibitor (ICI) efficacy. Antibiotics worsen clinical outcomes in patients receiving ICI. However, whether GM profiling and baseline antibiotic can be a biomarker of ICI efficacy in advanced non-small cell lung cancer (NSCLC) remains unknown. We prospectively collected baseline (pre-ICI) fecal samples and clinical data of 70 Japanese patients suffering from advanced NSCLC and treated them with anti-PD-1/PD-L1 antibodies as a first-line or treatment-refractory therapy. We performed 16S rRNA V3-V4 sequencing of gene amplicons of fecal samples, and bacteria diversity and differential abundance analysis was performed. The clinical endpoints were objective response rate (ORR), progression-free survival (PFS), overall survival (OS), and immune-related adverse events (irAE). ORR was 34%, and median PFS and OS were 5.2 and 16.2 months, respectively. Patients who received pre-ICI antibiotic had lower alpha diversity at baseline and underrepresentation of Ruminococcaceae UCG 13 and Agathobacter When analyzing antibiotic-free patients, alpha diversity correlated with OS. In addition, Ruminococcaceae UCG 13 and Agathobacter were enriched in patients with favorable ORR and PFS >6 months. Ruminococcaceae UCG 13 was enriched in patients with OS >12 months. GM differences were observed between patients who experienced low- versus high-grade irAE. We demonstrated the negative influence of antibiotic on the GM composition and identified the bacteria repertoire in patients experiencing favorable responses to ICI.See articles by Tomita et al., p. 1236, and Peng et al., p. 1251.

Elucidating the gut microbiota composition and the bioactivity of immunostimulatory commensals for the optimization of immune checkpoint inhibitors

Accumulating evidence from preclinical studies and human trials demonstrated the crucial role of the gut microbiota in determining the effectiveness of anticancer therapeutics such as immunogenic chemotherapy or immune checkpoint blockade. In summary, it appears that a diverse intestinal microbiota supports therapeutic anticancer responses, while a dysbiotic microbiota composition that lacks immunostimulatory bacteria or contains overabundant immunosuppressive species causes treatment failure. In this review, we explore preclinical and translational studies highlighting how eubiotic and dysbiotic microbiota composition can affect progression-free survival in cancer patients.

Gut Bacteria Composition Drives Primary Resistance to Cancer Immunotherapy in Renal Cell Carcinoma Patients

BACKGROUND

The development of immune checkpoint blockade (ICB) has revolutionized the clinical outcome of renal cell carcinoma (RCC). Nevertheless, improvement of durability and prediction of responses remain unmet medical needs. While it has been recognized that antibiotics (ATBs) decrease the clinical activity of ICB across various malignancies, little is known about the direct impact of distinct intestinal nonpathogenic bacteria (commensals) on therapeutic outcomes of ICB in RCC.

OBJECTIVE

To evaluate the predictive value of stool bacteria composition for ICB efficacy in a cohort of advanced RCC patients.

DESIGN, SETTING, AND PARTICIPANTS

We prospectively collected fecal samples from 69 advanced RCC patients treated with nivolumab and enrolled in the GETUG-AFU 26 NIVOREN microbiota translational substudy phase 2 trial (NCT03013335) at Gustave Roussy. We recorded patient characteristics including ATB use, prior systemic therapies, and response criteria. We analyzed 2994 samples of feces from healthy volunteers (HVs). In parallel, preclinical studies performed in RCC-bearing mice that received fecal transplant (FMT) from RCC patients resistant to ICB (NR-FMT) allowed us to draw a cause-effect relationship between gut bacteria composition and clinical outcomes for ICB. The influence of tyrosine kinase inhibitors (TKIs) taken before starting nivolumab on the microbiota composition has also been assessed.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Metagenomic data (MG) from whole genome sequencing (WGS) were analyzed by multivariate and pairwise comparisons/fold ratio to identify bacterial fingerprints related to ATB or prior TKI exposure and patients' therapeutic response (overall response and progression-free survival), and compared with the data from cancer-free donors.

RESULTS AND LIMITATIONS

Recent ATB use (n = 11; 16%) reduced objective response rates (from 28% to 9%, p < 0.03) and markedly affected the composition of the microbiota, facilitating the dominance of distinct species such as Clostridium hathewayi, which were also preferentially over-represented in stools from RCC patients compared with HVs. Importantly, TKIs taken prior to nivolumab had implications in shifting the microbiota composition. To establish a cause-effect relationship between gut bacteria composition and ICB efficacy, NR-FMT mice were successfully compensated with either FMT from responding RCC patients or beneficial commensals identified by WGS-MG (Akkermansia muciniphila and Bacteroides salyersiae).

CONCLUSIONS

The composition of the microbiota is influenced by TKIs and ATBs, and impacts the success of immunotherapy. Future studies will help sharpen the role of these specific bacteria and their potential as new biomarkers.

PATIENT SUMMARY

We used quantitative shotgun DNA sequencing of fecal microbes as well as preclinical models of fecal or bacterial transfer to study the association between stool composition and (pre)clinical outcome to immune checkpoint blockade. Novel insights into the pathophysiological relevance of intestinal dysbiosis in the prognosis of kidney cancer may lead to innovative therapeutic solutions, such as supplementation with probiotics to prevent primary resistance to therapy.

Primary adenocarcinoma of the seminal vesicle

Primary adenocarcinoma of the seminal vesicle is a rare condition with only about 60 cases described in the literature. The unusual characteristics of this disease makes diagnosis difficult and treatment strategies differ as there are no specific guidelines available. This report presents a case of adenocarcinoma of the seminal vesicle with lung metastases in which surgical and chemotherapeutic treatments have been carried out. The MVAC dose dense regimen following local resection seems effective in this scenario and may be used in the treatment of this disease.