Custom scoring based on ecological topology of gut microbiota associated with cancer immunotherapy outcome.

The gut microbiota influences the clinical responses of cancer patients to immunecheckpoint inhibitors (ICIs). However, there is no consensus definition of detrimental dysbiosis. Based on metagenomics (MG) sequencing of 245 non-small cell lung cancer (NSCLC) patient feces, we constructed species-level co-abundance networks that were clustered into species-interacting groups (SIGs) correlating with overall survival. Thirty-seven and forty-five MG species (MGSs) were associated with resistance (SIG1) and response (SIG2) to ICIs, respectively. When combined with the quantification of Akkermansia species, this procedure allowed a person-based calculation of a topological score (TOPOSCORE) that was validated in an additional 254 NSCLC patients and in 216 genitourinary cancer patients. Finally, this TOPOSCORE was translated into a 21-bacterial probe set-based qPCR scoring that was validated in a prospective cohort of NSCLC patients as well as in colorectal and melanoma patients. This approach could represent a dynamic diagnosis tool for intestinal dysbiosis to guide personalized microbiota-centered interventions.

Elevated Calprotectin and Abnormal Myeloid Cell Subsets Discriminate Severe from Mild COVID-19.

Blood myeloid cells are known to be dysregulated in coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2. It is unknown whether the innate myeloid response differs with disease severity and whether markers of innate immunity discriminate high-risk patients. Thus, we performed high-dimensional flow cytometry and single-cell RNA sequencing of COVID-19 patient peripheral blood cells and detected disappearance of non-classical CD14LowCD16High monocytes, accumulation of HLA-DRLow classical monocytes (Human Leukocyte Antigen - DR isotype), and release of massive amounts of calprotectin (S100A8/S100A9) in severe cases. Immature CD10LowCD101-CXCR4+/- neutrophils with an immunosuppressive profile accumulated in the blood and lungs, suggesting emergency myelopoiesis. Finally, we show that calprotectin plasma level and a routine flow cytometry assay detecting decreased frequencies of non-classical monocytes could discriminate patients who develop a severe form of COVID-19, suggesting a predictive value that deserves prospective evaluation.

Cross-tissue single-cell landscape of human monocytes and macrophages in health and disease.

Mononuclear phagocytes (MNPs) encompass dendritic cells, monocytes, and macrophages (MoMac), which exhibit antimicrobial, homeostatic, and immunoregulatory functions. We integrated 178,651 MNPs from 13 tissues across 41 datasets to generate a MNP single-cell RNA compendium (MNP-VERSE), a publicly available tool to map MNPs and define conserved gene signatures of MNP populations. Next, we generated a MoMac-focused compendium that revealed an array of specialized cell subsets widely distributed across multiple tissues. Specific pathological forms were expanded in cancer and inflammation. All neoplastic tissues contained conserved tumor-associated macrophage populations. In particular, we focused on IL4I1+CD274(PD-L1)+IDO1+ macrophages, which accumulated in the tumor periphery in a T cell-dependent manner via interferon-γ (IFN-γ) and CD40/CD40L-induced maturation from IFN-primed monocytes. IL4I1_Macs exhibited immunosuppressive characteristics through tryptophan degradation and promoted the entry of regulatory T cell into tumors. This integrated analysis provides a robust online-available platform for uniform annotation and dissection of specific macrophage functions in healthy and pathological states.

Physiologic colonic uptake of 18F-FDG on PET/CT is associated with clinical response and gut microbiome composition in patients with advanced non-small cell lung cancer treated with immune checkpoint inhibitors.

BACKGROUND: Immune checkpoint inhibitors (ICI) represent the backbone treatment for advanced non-small cell lung cancer (NSCLC). Emerging data suggest that increased gut microbiome diversity is associated with favorable response to ICI and that antibiotic-induced dysbiosis is associated with deleterious outcomes. 18F-FDG physiologic colonic uptake on PET/CT increases following treatment with antibiotics (ATB) and could act as a surrogate marker for microbiome composition and predict prognosis. The aim of this study was to determine if 18F-FDG physiologic colonic uptake prior to ICI initiation correlates with gut microbiome profiling and clinical outcomes in patients with advanced NSCLC. METHODS: Seventy-one patients with advanced NSCLC who underwent a PET/CT prior to ICI were identified. Blinded colonic contouring was performed for each colon segment and patients were stratified according to the median of the average colon SUVmax as well as for each segment in low vs. high SUVmax groups. Response rate, progression-free survival (PFS), and overall survival (OS) were compared in the low vs. high SUVmax groups. Gut microbiome composition was analyzed for 23 patients using metagenomics sequencing. RESULTS: The high colon SUVmax group had a higher proportion of non-responders (p = 0.033) and significantly shorter PFS (4.1 vs. 11.3 months, HR 1.94, 95% CI 1.11-3.41, p = 0.005). High caecum SUVmax correlated with numerically shorter OS (10.8 vs. 27.6 months, HR 1.85, 95% CI 0.97-3.53, p = 0.058). Metagenomics sequencing revealed distinctive microbiome populations in each group. Patients with low caecum SUVmax had higher microbiome diversity (p = 0.046) and were enriched with Bifidobacteriaceae, Lachnospiraceae, and Bacteroidaceae. CONCLUSIONS: Lower colon physiologic 18F-FDG uptake on PET/CT prior to ICI initiation was associated with better clinical outcomes and higher gut microbiome diversity in patients with advanced NSCLC. Here, we propose that 18F-FDG physiologic colonic uptake on PET/CT could serve as a potential novel marker of gut microbiome composition and may predict clinical outcomes in this population.

A new prognostic model for survival in second line for metastatic renal cell carcinoma: development and external validation.

BACKGROUND: In patients with metastatic renal cell carcinoma (mRCC), the oncologic benefit of second-line treatment for high volume tumors or presence of more than five risk factors remain to be defined. Our aim was to develop and externally validate a new model most likely to correctly predict overall survival (OS) categories in second line. METHOD: mRCC patients treated within clinical trials at Gustave Roussy Cancer Campus (GRCC) formed the discovery set. Patients from two phase III trials from Pfizer database (PFIZERDB), AXIS (NCT00678392), and INTORSECT (NCT00474786), formed the external validation set. New prognostic factors were analyzed using a multivariable Cox model with a backward selection procedure. Performance of the GRCC model and the prognostic classification scheme derived from it, measuring by R2, c-index, and calibration, was evaluated on the validation set and compared to MSKCC and IMDC models. RESULTS: Two hundred and twenty-one patients were included in the GRCC cohort and 855 patients in the PFIZERDB. Median OS was similar in the discovery and validation cohorts (16.8 [95% CI 12.9-21.7] and 15.3 [13.6-17.2] months, respectively). Backward selection procedure identified time from first to second-line treatment and tumor burden as new independent prognostic factors significantly associated to OS after adjusting for IMDC prognostic factors (HR 1.68 [1.23-2.31] and 1.43 [1.03-1.99], respectively). Dividing patients into four risk groups, based on the number of factors selected in GRCC model, median OS from the start of second line in the validation cohort was not reached (NE) [95% CI 24.9-NE] in the favorable risk group (n = 20), 21.8 months [18.6-28.2] in the intermediate-risk group (n = 367), 12.7 months [11.0-15.8] in the low poor-risk group (n = 347), and 5.5 months [4.7-6.4] in the high poor-risk group (n = 121). Finally, this model and its prognostic classification scheme provided the better fit, with higher R2 and higher c-index compared to other possible classification schemes. CONCLUSION: A new prognostic model was developed and validated to estimate overall survival of patients with previously treated mRCC. This model is an easy-to-use tool that allows accurate estimation of patient survival to inform decision making and follow-up after first line for mRCC.

Outcome of Patients with Renal Cell Carcinoma and Multiple Glandular Metastases Treated with Targeted Agents.

PURPOSE: Pancreatic metastases (PM) from renal cell carcinoma (RCC) have been associated with long-term survival. The aim of this study was to evaluate the outcome of RCC patients with multiple glandular metastases (MGM) treated with targeted therapies (TTs). METHODS: Sixty-four MGM patients treated between 1993 and 2014 were retrospectively identified from a database of 274 RCC patients with PM from 11 European centers. The survival of MGM patients was compared with that of both patients with PM only and a cohort of 325 RCC patients with non-GM (control group) treated with TTs. Survival was estimated using the Kaplan-Meier method and was statistically compared using the log-rank test. RESULTS: Fifty-six patients (88%) had at least 2 MGM, 7 patients (11%) had 3 MGM and 1 patient had 4 MGM, while non-GM were present in the remaining patients. The median overall survival (OS) was 54.2 months for MGM and 73.4 months for patients with PM only. The median OS in the control group was 22.7 months and statistically inferior to both MGM (p < 0.001) and PM patients (p < 0.001). CONCLUSION: MGM from RCC are associated with a remarkable survival. Despite some limitations, these findings suggest that GM might be considered a predictor of a favorable prognosis.

Clinical, pharmacodynamic and pharmacokinetic results of a prospective phase II study on oral metronomic vinorelbine and dexamethasone in castration-resistant prostate cancer patients.

The aim of the present study was to evaluate clinical activity, and the pharmacodynamic and pharmacokinetic profiles, of oral metronomic vinorelbine (VNR) plus dexamethasone (DEX) in metastatic castration-resistant prostate cancer (mCRPC) patients. Fourty-one patients (92 % chemotherapy-resistant) received 30 mg/day VNR p.o. thrice a week plus 1 mg/day DEX p.o. until disease progression. Plasma soluble B cell antigen 7 homolog 3 (sB7-H3), vascular endothelial growth factor (VEGF), and thrombospondin-1 (TSP-1), were measured by ELISA. Plasma VNR was detected using a LC-MS-MS system. The fraction of patients free of progression, defined by criteria of the Prostate Cancer Clinical Trials Working Group 2, at 3 months was 61 %. PSA decrease ≥50 % from baseline was observed in 35 % of patients. Median PFS and OS were 4 months (95 % CI, 2.8-6.9) and 17.5 months (95 % CI, 10.8-24.5), respectively. Toxicity was mild, and no grade 4 toxicities were found. The mean plasma VNR Cmax ranged from 1 to 2.7 ng/ml (Tmax 1.1 h) and no evidence of drug accumulation was found. A moderate relationship was found between plasma sB7-H3 and PSA values (r = 0.565; P = 0.0094) at the baseline. Increased PFS (11.3 vs. 2.8 months; P = 0.0298) was observed in patients with sB7-H3 levels <30.25 ng/mL. Plasma VEGF AUC0-24day increased in non-responders (P < 0.0001), whereas responders maintained higher plasma TSP-1 AUC0-24day (P = 0.0063). In conclusion, metronomic VNR plus DEX showed favourable activity, and a low toxicity profile, in mCRPC patients. Plasma sB7-H3, VEGF and TSP-1 levels are potential pharmacodynamic markers at the reached low plasma concentrations of vinorelbine metronomically administered.

Metabolic syndrome in castration-resistant prostate cancer patients treated with abiraterone.

BACKGROUND: Metabolic syndrome (MS) has not yet been studied in castration-resistant prostate cancer (CRPC) men treated with novel hormonal therapies. The study aims to assess the impact of MS on outcome from time starting abiraterone. PATIENTS AND METHODS: We retrospectively evaluated a consecutive series of metastatic CRPC patients treated with abiraterone after docetaxel failure. MS, as defined by modified Adult Treatment Panel (ATP) III criteria, was assessed at the time of initiation of abiraterone, during treatment and follow-up. RESULTS: Sixty-seven of 178 patients evaluated (37.6%) met MS criteria at baseline, before abiraterone initiation, whereas for 11 (9.9%) without MS before treatment with abiraterone this occurred during treatment. Median PFS was equal to 4.7 months for patients with MS versus 9 months for those without MS. Patients with MS had an increased risk of 71% of progression or death for all causes than patients without MS (HR = 1.7, 95% CI [1.2-2.4], P = 0.03). Median OS was 14.7 months and 22.3 months in patients with and without MS, respectively. After adjusting for covariates, MS resulted not significantly associated to OS (HR = 1.42, 95% CI [0.91-2.22], P = 0.073). CONCLUSIONS: The presence of MS is a significant risk factor for shorter PFS in CRPC patients treated with abiraterone, even if it does not show a significant impact on OS. A prospective evaluation is warranted.

Sunitinib, pazopanib or sorafenib for the treatment of patients with late relapsing metastatic renal cell carcinoma.

PURPOSE: Late recurrence of renal cell carcinoma is not a rare event. In this retrospective study we investigate the clinicopathological features and the outcome of patients treated with sorafenib, sunitinib and pazopanib for late relapsing renal cell carcinoma. MATERIALS AND METHODS: Data were collected from 21 Italian centers involved in the treatment of metastatic renal cell carcinoma. Late relapse was defined as more than 5 years after initial radical nephrectomy. RESULTS: A total of 2,490 patients were screened and 269 (11%) were included in the study. First line therapy was sunitinib in 190 patients (71%), sorafenib in 58 (21%) and pazopanib in 21 (8%). Median progression-free survival was 20.0 months for sunitinib (95% CI 17.0-25.1), and 14.1 months for sorafenib (95% CI 11.0-29.0) and pazopanib (95% CI 11.2-not reported). On multivariate analysis MSKCC score and metastases to lymph nodes, liver and brain were associated with worst overall survival, while pancreatic metastases were associated with longer survival. Furthermore, age, MSKCC score and brain metastases were associated with worst progression-free survival. CONCLUSIONS: Patients with late relapsing renal cell carcinoma seem to present a characteristic pattern of metastatic spread without showing significant differences in terms of progression-free survival among sorafenib, sunitinib and pazopanib.

Surgical resection does not improve survival in patients with renal metastases to the pancreas in the era of tyrosine kinase inhibitors.

BACKGROUND: The aim of this study was to compare survival of resected and unresected patients in a large cohort of patients with metastases to the pancreas from renal cell carcinoma (PM-RCC). METHODS: Data from 16 Italian centers involved in the treatment of metastatic RCC were retrospectively collected. The Kaplan-Meier and log-rank test methods were used to evaluate overall survival (OS). Clinical variables considered were sex, age, concomitant metastasis to other sites, surgical resection of PM-RCC, and time to PM-RCC occurrence. RESULTS: Overall, 103 consecutive patients with radically resected primary tumors were enrolled in the analysis. PM-RCCs were synchronous in only three patients (3 %). In 56 patients (54 %), the pancreas was the only metastatic site, whereas in the other 47 patients, lung (57 %), lymph nodes (28 %), and liver (21 %) were the most common concomitant metastatic sites. Median time for PM-RCC occurrence was 9.6 years (range 0-24 years) after nephrectomy. Surgical resection of PM-RCC was performed in 44 patients (median OS 103 months), while 59 patients were treated with tyrosine kinase inhibitors (TKIs; median OS 86 months) (p = 0.201). At multivariate analysis, Memorial Sloan Kettering Cancer Center risk group was the only independent prognostic factor. None of the other clinical variables, such as age, sex, pancreatic surgery, or the presence of concomitant metastases, were significantly associated with outcome in PM-RCC patients. CONCLUSIONS: The presence of PM-RCC is associated with a long survival, and surgical resection does not improve survival in comparison with TKI therapy. However, surgical resection leads to a percentage of disease-free PM-RCC patients.

Docetaxel rechallenge in metastatic castration-resistant prostate cancer: any place in the modern treatment scenario? An intention to treat evaluation.

BACKGROUND: We evaluated the possible advantages of a docetaxel (DCT) rechallenge strategy in metastatic castration-resistant prostate cancer (mCRPC) patients, also given the possible earlier positioning of this treatment option in the modern scenario. PATIENTS & METHODS: All mCRPC patients planned for DCT chemotherapy rechallenge in our institutions were evaluated. RESULTS: Of 128 patients, 98 achieved disease control on the initial DCT round. After a treatment holiday of 8.3 months, the 98 responsive patients underwent a second DCT round, with 56 cases achieving again disease control. After a 5.7-month off-treatment period, 32 of these cases underwent a third DCT round, and 16 responded. Lastly, after a further 4.2-month treatment holiday, eight patients underwent a fourth DCT round and two responded. Median time to definitive disease progression for the whole population was 16.4 months. CONCLUSIONS: Rechallenge with DCT may be considered a suitable treatment option for mCRPC patients recurring after a successful DCT chemotherapy. The interest in this strategy may be increased because of the showed efficacy of early DCT chemotherapy in patients with bulky disease (CHAARTED study) and the potential lower efficacy of the new hormonal agents abiraterone acetate and enzalutamide when used in a immediate sequencing.

Docetaxel plus oral metronomic cyclophosphamide: a phase II study with pharmacodynamic and pharmacogenetic analyses in castration-resistant prostate cancer patients.

BACKGROUND: Docetaxel plus prednisone is currently the standard first-line treatment in metastatic castration-resistant prostate cancer (mCRPC). The aim of this study was to assess the clinical activity and pharmacodynamic/pharmacogenetic profile of docetaxel plus prednisone in combination with metronomic cyclophosphamide in mCRPC patients. METHODS: Forty-one chemotherapy-naive patients received docetaxel (60 mg/m(2) intravenously every 3 weeks up to 12 cycles) and, from day 2, prednisone 10 mg/day, celecoxib 400 mg/day, and metronomic cyclophosphamide 50 mg/day, continuously. Plasma VEGF and bFGF were detected by ELISA. Real-time PCR-SNP analysis of VEGF gene was performed using an ABI PRISM 7900HT SDS and TaqMan SNP genotyping. RESULTS: Eighty-seven percent of patients were free of progression at 6 months. A decrease in prostate-specific antigen ≥50% was observed in 82% of 39 evaluable patients, with a median time to progression of 12.3 months. Grade 3 adverse events were neutropenia (5%), thrombocytopenia, diarrhea, and stomatitis (2.5%). Median PFS and OS were 14.9 months (95% CI, 9.2-15.3 months) and 33.3 months (95% CI, 23-35.6 months), respectively. Of 11 patients (28%) with evaluable disease, 5 (44%) achieved a complete response, 2 (11%) a partial response, and 2 (11%) stable disease, whereas 2 showed disease progression. The -1154A/G VEGF polymorphism, plasma VEGF, and bFGF after the first cycle of chemotherapy may represent useful pharmacodynamic markers to predict better outcomes. CONCLUSIONS: The combination of docetaxel and oral metronomic chemotherapy is effective and well tolerated in mCRPC patients and may deserve further evaluation.

Sorafenib as first- or second-line therapy in patients with metastatic renal cell carcinoma in a community setting.

AIM: The Italian Retrospective Analysis of Sorafenib as First or Second Target Therapy study assessed the efficacy and safety of sorafenib in metastatic renal cell carcinoma patients treated in the community. PATIENTS & METHODS: Patients receiving first- or second-line single-agent sorafenib between January 2008 and December 2010 were eligible. Retrospective data collection started in 2012 and covers at least 1-year follow-up. The primary end point was overall survival (OS). RESULTS: Median OS was 17.2 months (95% CI: 15.5-19.6): 19.9 months (95% CI: 15.9-25.3) in patients treated with first-line sorafenib and 16.3 months (95% CI: 13.1-18.2) with second-line sorafenib. Overall median (95% CI) progression-free survival was 5.9 months (95% CI: 4.9-6.7): 6.6 (95% CI: 4.9-9.3) and 5.3 months (95% CI: 4.3-6.0) in first- and second-line patients, respectively. CONCLUSION: The efficacy and safety of sorafenib in routine community practice was generally good, especially in relation to OS in patients treated in the second line, where results were similar to those seen in recent prospective clinical trials.

Characterizing the immune tumor microenvironment in ALK fusion-positive lung cancer: state-of-the-art and therapeutical implications.

INTRODUCTION: Approximately 5% of non-small cell lung cancer (NSCLC), exhibits anaplastic lymphoma kinase (ALK) rearrangements. EML4-ALK fusions account for over 90% of ALK rearrangements in NSCLC. The advent of treatment targeting ALK has significantly improved survival rates in patients with advanced ALK-positive NSCLC. However, the emergence of resistance mechanisms and the subsequent progression disease inevitably occurs. The tumor immune microenvironment (TIME) plays a pivotal role in lung cancer, influencing disease development, patient's outcomes, and response to treatments. AREAS COVERED: The aim of this review is to provide a comprehensive characterization of the TIME in ALK rearranged NSCLC and its intrinsic plasticity under treatment pressure. EXPERT OPINION: Recognizing the fundamental role of the TIME in cancer progression has shifted the paradigm from a tumor cell-centric perspective to the understanding of a complex tumor ecosystem. Understanding the intricate dynamics of the TIME, its influence on treatment response, and the potential of immunotherapy in patients with ALK-positive NSCLC are currently among the primary research objectives in this patient population.

Faecalibaterium prausnitzii strain EXL01 boosts efficacy of immune checkpoint inhibitors.

Gut microbiota impacts responses to immune checkpoint inhibitors (ICI). A high level of Faecalibacterium prausnitzii have been associated with a positive response to ICI in multiple cancer types. Here, based on fecal shotgun metagenomics data, we show in two independent cohorts of patients with non-small cell lung cancer and advanced melanoma that a high level of F. prausnitzii at baseline is positively associated with a better clinical response to ICI. In MCA205 tumor-bearing mice, administration of F. prausnitzii strain EXL01, already in clinical development for Inflammatory Bowel Disease, restores the anti-tumor response to ICI in the context of antibiotic-induced microbiota perturbation at clinical and tumor transcriptomics level. In vitro, EXL01 strain enhances T cell activation in the presence of ICI. Interestingly, oral administration of EXL01 strain did not induce any change in fecal microbiota diversity or composition, suggesting a direct effect on immune cells in the small intestine. F. prausnitzii strain EXL01 will be evaluated as an adjuvant to ICI in multiple cancers in the near future.

Antibiotics are associated with worse outcomes in lung cancer patients treated with chemotherapy and immunotherapy.

Anti-PD(L)-1 inhibition combined with platinum doublet chemotherapy (Chemo-IO) has become the most frequently used standard of care regimen in patients with non-small cell lung cancer (NSCLC). The negative impact of antibiotics on clinical outcomes prior to anti-PD(L)-1 inhibition monotherapy (IO) has been demonstrated in multiple studies, but the impact of antibiotic exposure prior to initiation of Chemo-IO is controversial. We assessed antibiotic exposures at two time windows: within 60 days prior to therapy (-60 d window) and within 60 days prior to therapy and 42 days after therapy (-60 + 42d window) in 2028 patients with advanced NSCLC treated with Chemo-IO and IO monotherapy focusing on objective response rate (ORR: rate of partial response and complete response), progression-free survival (PFS), and overall survival (OS). We also assessed impact of antibiotic exposure in an independent cohort of 53 patients. Univariable and multivariable analyses were conducted along with a meta-analysis from similar studies. For the -60 d window, in the Chemo-IO group (N = 769), 183 (24%) patients received antibiotics. Antibiotic exposure was associated with worse ORR (27% vs 40%, p = 0.001), shorter PFS (3.9 months vs. 5.9 months, hazard ratio [HR] 1.35, 95%CI 1.1,1.6, p = 0.0012), as well as shorter OS (10 months vs. 15 months, HR 1.50, 95%CI 1.2,1.8, p = 0.00014). After adjusting for known prognostic factors in NSCLC, antibiotic exposure was independently associated with worse PFS (HR 1.39, 95%CI 1.35,1.7, p = 0.002) and OS (HR 1.61, 95%CI 1.28,2.03, p < 0.001). Similar results were obtained in the -60 + 42d window, and also in an independent cohort. In a meta-analysis of patients with NSCLC treated with Chemo-IO (N = 4) or IO monotherapy (N = 13 studies) antibiotic exposure before treatment was associated with worse OS among all patients (n = 11,351) (HR 1.93, 95% CI 1.52, 2.45) and Chemo-IO-treated patients (n = 1201) (HR 1.54, 95% CI 1.28, 1.84). Thus, antibiotics exposure prior to Chemo-IO is common and associated with worse outcomes, even after adjusting for other factors. These results highlight the need to implement antibiotic stewardship in routine oncology practice.

Gut microbiome predicts gastrointestinal toxicity outcomes from chemoradiation therapy in patients with head and neck squamous cell carcinoma.

OBJECTIVES: Chemoradiation (CRT) in patients with locally advanced head and neck squamous cell cancer (HNSCC) is associated with significant toxicities, including mucositis. The gut microbiome represents an emerging hallmark of cancer and a potentially important biomarker for CRT-related adverse events. This prospective study investigated the association between the gut microbiome composition and CRT-related toxicities in patients with HNSCC, including mucositis. MATERIALS AND METHODS: Stool samples from patients diagnosed with locally advanced HNSCC were prospectively collected prior to CRT initiation and analyzed using shotgun metagenomic sequencing to evaluate gut microbiome composition at baseline. Concurrently, clinicopathologic data, survival outcomes and the incidence and grading of CRT-emergent adverse events were documented in all patients. RESULTS: A total of 52 patients were included, of whom 47 had baseline stool samples available for metagenomic analysis. Median age was 62, 83 % patients were men and 54 % had stage III-IV disease. All patients developed CRT-induced mucositis, including 42 % with severe events (i.e. CTCAE v5.0 grade ≥ 3) and 25 % who required enteral feeding. With a median follow-up of 26.5 months, patients with severe mucositis had shorter overall survival (HR = 3.3, 95 %CI 1.0-10.6; p = 0.02) and numerically shorter progression-free survival (HR = 2.8, 95 %CI, 0.8-9.6; p = 0.09). The gut microbiome beta-diversity of patients with severe mucositis differed from patients with grades 1-2 mucositis (p = 0.04), with enrichment in Mediterraneibacter (Ruminococcus gnavus) and Clostridiaceae family members, including Hungatella hathewayi. Grade 1-2 mucositis was associated with enrichment in Eubacterium rectale, Alistipes putredinis and Ruminococcaceae family members. Similar bacterial profiles were observed in patients who required enteral feeding. CONCLUSION: Patients who developed severe mucositis had decreased survival and enrichment in specific bacteria associated with mucosal inflammation. Interestingly, these same bacteria have been linked to immune checkpoint inhibitor resistance.

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.

Longitudinal gut microbiome changes in immune checkpoint blockade-treated advanced melanoma.

Multiple clinical trials targeting the gut microbiome are being conducted to optimize treatment outcomes for immune checkpoint blockade (ICB). To improve the success of these interventions, understanding gut microbiome changes during ICB is urgently needed. Here through longitudinal microbiome profiling of 175 patients treated with ICB for advanced melanoma, we show that several microbial species-level genome bins (SGBs) and pathways exhibit distinct patterns from baseline in patients achieving progression-free survival (PFS) of 12 months or longer (PFS ≥12) versus patients with PFS shorter than 12 months (PFS <12). Out of 99 SGBs that could discriminate between these two groups, 20 were differentially abundant only at baseline, while 42 were differentially abundant only after treatment initiation. We identify five and four SGBs that had consistently higher abundances in patients with PFS ≥12 and <12 months, respectively. Constructing a log ratio of these SGBs, we find an association with overall survival. Finally, we find different microbial dynamics in different clinical contexts including the type of ICB regimen, development of immune-related adverse events and concomitant medication use. Insights into the longitudinal dynamics of the gut microbiome in association with host factors and treatment regimens will be critical for guiding rational microbiome-targeted therapies aimed at enhancing ICB efficacy.

Melanoma and microbiota: Current understanding and future directions.

Over the last decade, the composition of the gut microbiota has been found to correlate with the outcomes of cancer patients treated with immunotherapy. Accumulating evidence points to the various mechanisms by which intestinal bacteria act on distal tumors and how to harness this complex ecosystem to circumvent primary resistance to immune checkpoint inhibitors. Here, we review the state of the microbiota field in the context of melanoma, the recent breakthroughs in defining microbial modes of action, and how to modulate the microbiota to enhance response to cancer immunotherapy. The host-microbe interaction may be deciphered by the use of "omics" technologies, and will guide patient stratification and the development of microbiota-centered interventions. Efforts needed to advance the field and current gaps of knowledge are also discussed.