Altered salivary microbiota associated with high-sugar beverage consumption.

The human oral microbiome may alter oral and systemic disease risk. Consuming high sugar content beverages (HSB) can lead to caries development by altering the microbial composition in dental plaque, but little is known regarding HSB-specific oral microbial alterations. Therefore, we conducted a large, population-based study to examine associations of HSB intake with oral microbiome diversity and composition. Using mouthwash samples of 989 individuals in two nationwide U.S. cohorts, bacterial 16S rRNA genes were amplified, sequenced, and assigned to bacterial taxa. HSB intake was quantified from food frequency questionnaires as low (< 1 serving/week), medium (1-3 servings/week), or high (> 3 servings/week). We assessed overall bacterial diversity and presence of specific taxa with respect to HSB intake in each cohort separately and combined in a meta-analysis. Consistently in the two cohorts, we found lower species richness in high HSB consumers (> 3 cans/week) (p = 0.027), and that overall bacterial community profiles differed from those of non-consumers (PERMANOVA p = 0.040). Specifically, presence of a network of commensal bacteria (Lachnospiraceae, Peptostreptococcaceae, and Alloprevotella rava) was less common in high compared to non-consumers, as were other species including Campylobacter showae, Prevotella oulorum, and Mycoplasma faucium. Presence of acidogenic bacteria Bifodobacteriaceae and Lactobacillus rhamnosus was more common in high consumers. Abundance of Fusobacteriales and its genus Leptotrichia, Lachnoanaerobaculum sp., and Campylobacter were lower with higher HSB consumption, and their abundances were correlated. No significant interaction was found for these associations with diabetic status or with microbial markers for caries (S. mutans) and periodontitis (P. gingivalis). Our results suggest that soft drink intake may alter the salivary microbiota, with consistent results across two independent cohorts. The observed perturbations of overrepresented acidogenic bacteria and underrepresented commensal bacteria in high HSB consumers may have implications for oral and systemic disease risk.

Germline immunomodulatory expression quantitative trait loci (ieQTLs) associated with immune-related toxicity from checkpoint inhibition.

BACKGROUND: Immune checkpoint inhibition (ICI) has improved clinical outcomes for metastatic melanoma patients; however, 65-80% of patients treated with ICI experience immune-related adverse events (irAEs). Given the plausible link of irAEs with underlying host immunity, we explored whether germline genetic variants controlling the expression of 42 immunomodulatory genes were associated with the risk of irAEs in melanoma patients treated with the single-agent anti-CTLA-4 antibody ipilimumab (IPI). METHODS: We identified 42 immunomodulatory expression quantitative trait loci (ieQTLs) most significantly associated with the expression of 382 immune-related genes. These germline variants were genotyped in IPI-treated melanoma patients, collected as part of a multi-institutional collaboration. We tested the association of ieQTLs with irAEs in a discovery cohort of 95 patients, followed by validation in an additional 97 patients. RESULTS: We found that the alternate allele of rs7036417, a variant linked to increased expression of SYK, was strongly associated with an increased risk of grade 3-4 toxicity [odds ratio (OR) = 7.46; 95% confidence interval (CI) = 2.65-21.03; p = 1.43E-04]. This variant was not associated with response (OR = 0.90; 95% CI = 0.37-2.21; p = 0.82). CONCLUSION: We report that rs7036417 is associated with increased risk of severe irAEs, independent of IPI efficacy. SYK plays an important role in B-cell/T-cell expansion, and increased pSYK has been reported in patients with autoimmune disease. The association between rs7036417 and IPI irAEs in our data suggests a role of SYK overexpression in irAE development. These findings support the hypothesis that inherited variation in immune-related pathways modulates ICI toxicity and suggests SYK as a possible future target for therapies to reduce irAEs.

Kinase Insert Domain Receptor Q472H Pathogenic Germline Variant Impacts Melanoma Tumor Growth and Patient Treatment Outcomes.

BACKGROUND: We previously reported a higher incidence of a pathogenic germline variant in the kinase insert domain receptor (KDR) in melanoma patients compared to the general population. Here, we dissect the impact of this genotype on melanoma tumor growth kinetics, tumor phenotype, and response to treatment with immune checkpoint inhibitors (ICIs) or targeted therapy. METHODS: The KDR genotype was determined and the associations between the KDR Q472H variant (KDR-Var), angiogenesis, tumor immunophenotype, and response to MAPK inhibition or ICI treatment were examined. Melanoma B16 cell lines were transfected with KDR-Var or KDR wild type (KDR-WT), and the differences in tumor kinetics were evaluated. We also examined the impact of KDR-Var on the response of melanoma cells to a combination of VEGFR inhibition with MAPKi. RESULTS: We identified the KDR-Var genotype in 81/489 (37%) patients, and it was associated with a more angiogenic (p = 0.003) and immune-suppressive tumor phenotype. KDR-Var was also associated with decreased PFS to MAPKi (p = 0.022) and a trend with worse PFS to anti-PD1 therapy (p = 0.06). KDR-Var B16 murine models had increased average tumor volume (p = 0.0027) and decreased CD45 tumor-infiltrating lymphocytes (p = 0.0282). The anti-VEGFR treatment Lenvatinib reduced the tumor size of KDR-Var murine tumors (p = 0.0159), and KDR-Var cells showed synergistic cytotoxicity to the combination of dabrafenib and lenvatinib. CONCLUSIONS: Our data demonstrate a role of germline KDR-Var in modulating melanoma behavior, including response to treatment. Our data also suggest that anti-angiogenic therapy might be beneficial in patients harboring this genotype, which needs to be tested in clinical trials.

Elevated dietary carbohydrate and glycemic intake associate with an altered oral microbial ecosystem in two large U.S. cohorts.

The human oral microbiome is associated with chronic diseases including cancer. However, our understanding of its relationship with diet is limited. We assessed the associations between carbohydrate and glycemic index (GI) with oral microbiome composition in 834 non-diabetic subjects from the NCI-PLCO and ACS-CPSII cohorts. The oral microbiome was characterized using 16Sv3-4 rRNA-sequencing from oral mouthwash samples. Daily carbohydrate and GI were assessed from food frequency questionnaires. We used linear regression, permutational MANOVA, and negative binomial Generalized Linear Models (GLM) to test associations of diet with α- and ß-diversity and taxon abundance (adjusting for age, sex, cohort, BMI, smoking, caloric intake, and alcohol). A q-value (FDR-adjusted P-value) of <0.05 was considered significant. Oral bacterial α-diversity trended higher in participants in the highest quintiles of carbohydrate intake, with marginally increased richness and Shannon diversity (p-trend=0.06 and 0.07). Greater carbohydrate intake was associated with greater abundance of class Fusobacteriia (q=0.02) and genus Leptotrichia (q=0.01) and with lesser abundance of an Actinomyces OTU (q=4.7E-04). Higher GI was significantly related to greater abundance of genus Gemella (q=0.001). This large, nationwide study provides evidence that diets high in carbohydrates and GI may influence the oral microbiome.

Phase II clinical and immune correlate study of adjuvant nivolumab plus ipilimumab for high-risk resected melanoma.

BACKGROUND: Adjuvant therapy for high-risk resected melanoma with programmed cell-death 1 blockade results in a median relapse-free survival (RFS) of 5 years. The addition of low dose ipilimumab (IPI) to a regimen of adjuvant nivolumab (NIVO) in CheckMate-915 did not result in increased RFS. A pilot phase II adjuvant study of either standard dose or low dose IPI with NIVO was conducted at two centers to evaluate RFS with correlative biomarker studies. METHODS: Patients with resected stages IIIB/IIIC/IV melanoma received either IPI 3 mg/kg and NIVO 1 mg/kg (cohort 4) or IPI 1 mg/kg and NIVO 3 mg/kg (cohorts 5 and 6) induction therapy every 3 weeks for 12 weeks, followed by maintenance NIVO. In an amalgamated subset of patients across cohorts, peripheral T cells at baseline and on-treatment were assessed by flow cytometry and RNA sequencing for exploratory biomarkers. RESULTS: High rates of grade 3-4 adverse events precluded completion of induction therapy in 50%, 35% and 7% of the patients in cohorts 4, 5 and 6, respectively. At a median of 63.9 months of follow-up, 16/56 patients (29%) relapsed. For all patients, at 5 years, RFS was 71% (95% CI: 60 to 84), and overall survival was 94% (95% CI: 88 to 100). Expansion of CD3+CD4+CD38+CD127-GARP- T cells, an on-treatment increase in CD39 expression in CD8+ T cells, and T-cell expression of phosphorylated signal-transducer-and-activator-of-transcription (STAT)2 and STAT5 were associated with relapse. CONCLUSIONS: Adjuvant IPI/NIVO at the induction doses used resulted in promising relapse-free and overall survival, although with a high rate of grade 3-4 adverse events. Biomarker analyses highlight an association of ectoenzyme-expressing T cells and STAT signaling pathways with relapse, warranting future validation. TRIAL REGISTRATION NUMBER: NCT01176474 and NCT02970981.

Circulating growth factor concentrations and breast cancer risk: a nested case-control study of IGF-1, IGFBP-3, and breast cancer in a family-based cohort.

BACKGROUND: Insulin-like growth factor 1 (IGF-1) and binding protein 3 (IGFBP-3) are associated with breast cancer in women at average risk of cancer. Less is known whether these biomarkers also predict risk in women with breast cancer family history. METHODS: We conducted a nested case-control study within the New York site of the Breast Cancer Family Registry (BCFR, n = 80 cases, 156 controls), a cohort enriched for breast cancer family history. Using conditional logistic regression, we estimated the association between IGF-1 and IGFBP-3 levels and breast cancer risk and examined whether this risk differed by predicted absolute breast cancer risk based on pedigree models. RESULTS: The overall association between IGF-1 or IGFBP-3 elevation (≥ median in controls) and breast cancer risk was elevated, but not statistically significant (IGF-1 OR = 1.37, 95% CI = 0.66-2.85; IGFBP-3 OR = 1.62, 95% CI = 0.81-3.24). Women with elevated predicted absolute 10-year risk ≥ 3.4% and elevated IGFBP-3 (≥ median) had more than a 3-fold increased risk compared to women with lower predicted absolute 10-year risk (< 3.4%) and low IGFBP-3 (OR = 3.47 95% CI = 1.04-11.6). CONCLUSIONS: These data offer some support that the overall magnitude of the associations between IGF-1 and IGFBP3 seen in average risk cohorts may be similar in women enriched with a strong breast cancer family history.

A phase 1b dose expansion study of the pan-class I PI3K inhibitor buparlisib (BKM120) plus carboplatin and paclitaxel in PTEN deficient tumors and with dose intensified carboplatin and paclitaxel.

Purpose We previously reported the phase I dose escalation study of buparlisib, a pan-class 1A PI3K inhibitor, combined with platinum/taxane-based chemotherapy in patients with advanced solid tumors. The combination was well tolerated and promising preliminary efficacy was observed in PTEN deficient tumors. This phase I dose expansion study now evaluates buparlisib plus high dose carboplatin and paclitaxel in unselected patients with advanced solid tumors and buparlisib plus standard dose carboplatin and paclitaxel in patients with PTEN deficient tumors (ClinicalTrials.gov, NCT01297452). Methods There were two expansion cohorts: Cohort A received continuous buparlisib (100 mg/daily) orally plus high dose carboplatin AUC 6 and paclitaxel 200 mg/m2; Cohort B treated patients with PTEN deficient tumors only and they received the recommended phase II dose (RP2D) of continuous buparlisib (100 mg/daily) orally plus standard dose carboplatin AUC 5 and paclitaxel 175 mg/m2. Both cohorts received chemotherapy intravenously on day 1 of the 21-day cycle with pegfilgrastim support. Primary endpoint in Cohort A was to evaluate the safety and tolerability of chemotherapy dose intensification with buparlisib and in Cohort B was to describe preliminary efficacy of the combination among patients with tumors harboring a PTEN mutation or homozygous deletion. Results 14 subjects were enrolled, 7 in Cohort A and 7 in Cohort B. Dose reductions were required in 5 (71%) and 3 (43%) patients, in cohort A and B respectively. Grade 3 adverse events in Cohort A included lymphopenia (n = 5 [71%]), hyperglycemia (n = 2, [29%]), diarrhea (n = 2, [29%]) and rash (n = 2, [29%]) and in cohort B included lymphopenia (n = 5 [71%]), hyperglycemia (n = 4 [57%]) and neutropenia (n = 2 [29%]. The mean number of cycles on protocol was 6. The overall objective response rate was 14% (2 /14). No objective responses were observed in the PTEN deficient cohort. Four out of 6 patients with stable disease (SD) had SD or better for ≥6 cycles, 2 of which had PTEN deficient tumors. Conclusion The addition of buparlisib to high dose carboplatin and paclitaxel was not tolerable. The combination did not reveal significant clinical activity amongst a small and heterogenous group of PTEN deficient tumors.

Parallel phase Ib studies of two schedules of buparlisib (BKM120) plus carboplatin and paclitaxel (q21 days or q28 days) for patients with advanced solid tumors.

PURPOSE: Phosphatidylinositol-3-kinase I (PI3K) inhibition sensitizes a wide range of cancer cell lines to platinum/taxane-based chemotherapy. This phase I study combines buparlisib, a pan-class 1A PI3K inhibitor, with two schedules of carboplatin and paclitaxel for patients with advanced solid tumors (ClinicalTrials.gov, NCT01297452). METHODS: There were two regimens: Group 1 received carboplatin AUC 5 and paclitaxel 175 mg/m(2), on day 1 of a 21-day cycle with pegfilgrastim support; Group 2 received carboplatin AUC 5 (day 1) and paclitaxel 80 mg/m(2) (days 1, 8, and 15) on a 28-day cycle without growth factor support. In both groups, three dose levels of buparlisib were explored: 50, 80, and 100 mg/day. Primary endpoint was to identify recommended phase II doses of buparlisib in both groups. RESULTS: Thirty subjects enrolled, 16 in Group 1 and 14 in Group 2. The DLTs were elevated alkaline phosphatase (n = 1) and uncomplicated neutropenia (n = 2). The median numbers of cycles were 5 (Group 1) and 6 (Group 2). The MTDs for buparlisib were 100 mg/day in Group 1 and 80 mg/day in Group 2. Among 25 patients with measurable disease, the confirmed objective response rate was 20% (one complete response, four partial responses). Among three patients with known loss of PTEN expression, all derived clinical benefit from treatment. CONCLUSION: The addition of buparlisib to carboplatin + paclitaxel was well tolerated, and preliminary activity was notable against tumors with loss of PTEN expression.