An Explainable Graph Neural Framework to Identify Cancer-Associated Intratumoral Microbial Communities.

Microbes are extensively present among various cancer tissues and play critical roles in carcinogenesis and treatment responses. However, the underlying relationships between intratumoral microbes and tumors remain poorly understood. Here, a MIcrobial Cancer-association Analysis using a Heterogeneous graph transformer (MICAH) to identify intratumoral cancer-associated microbial communities is presented. MICAH integrates metabolic and phylogenetic relationships among microbes into a heterogeneous graph representation. It uses a graph transformer to holistically capture relationships between intratumoral microbes and cancer tissues, which improves the explainability of the associations between identified microbial communities and cancers. MICAH is applied to intratumoral bacterial data across 5 cancer types and 5 fungi datasets, and its generalizability and reproducibility are demonstrated. After experimentally testing a representative observation using a mouse model of tumor-microbe-immune interactions, a result consistent with MICAH's identified relationship is observed. Source tracking analysis reveals that the primary known contributor to a cancer-associated microbial community is the organs affected by the type of cancer. Overall, this graph neural network framework refines the number of microbes that can be used for follow-up experimental validation from thousands to tens, thereby helping to accelerate the understanding of the relationship between tumors and intratumoral microbiomes.

Resiliency among older adults receiving lung cancer treatment (ROAR-LCT): A novel supportive care intervention for older adults with advanced lung cancer.

INTRODUCTION: Novel supportive care interventions designed for an aging population with lung cancer are urgently needed. We aimed to determine the feasibility of a novel supportive care physical therapy (PT) plus progressive muscle relaxation (PMR) intervention delivered to older adults with advanced lung cancer in the United States (US). MATERIALS AND METHODS: This clinical trial, Resiliency Among Older Adults Receiving Lung Cancer Treatment (ROAR-LCT: NCT04229381), recruited adults aged ≥60 years with unresectable stage III/IV non-small cell (NSCLC) or small cell lung cancer (SCLC) receiving cancer treatment at The James Thoracic Oncology Center (planned enrollment, N = 20). There were no exclusion criteria pertaining to performance status, laboratory values, prior cancer diagnoses, comorbidities, or brain metastases. Participants were evaluated by PT and psychology and given an exercise pedaler, resistance bands, a relaxation voice recording, and instructions at study initiation. Participants were evaluated in-person by PTs and psychologists at the start and end of the 12-session intervention, with the intervening sessions conducted via virtual health. Participants completed self-reported measures of functional status, symptoms, and mood longitudinally with the following instruments: EQ-5D-5L, Patient Health Questionnaire-9, and General Anxiety Disorder-7. PT assessments included the Short Physical Performance Battery (SPPB) and the two-minute walk test. Feasibility was defined as at least 60% of participants completing at least 70% of all intervention sessions. Optional gut microbiome samples and activity monitoring data (ActiGraph®) were also collected. RESULTS: The ROAR-LCT study concluded after consenting 22 patients. Among the 22 consented, 18 (81.8%) started the intervention; 11 participants (61.1%) completed at least 70% of all study sessions. All participants with SCLC completed the intervention. Reasons for withdrawal included progression of disease or hospitalization. The majority (88.9%) of patients who started were able to complete at least one virtual health session. Participants' functional status, SPPB, depression, and anxiety scores were stable from pre- to post-intervention. Participants who withdrew had worse baseline scores across domains. Seven microbiome and six ActiGraph® samples were collected. DISCUSSION: This is one of the first PT + PMR supportive care interventions using virtual health among older adults with advanced lung cancer to achieve feasibility in the US.

From poo to promise: Fecal microbiota transplants support immunotherapy re-sensitization in solid tumors.

Fecal microbiota transplants (FMTs) recently entered the cancer therapeutics field as a method to resensitize treatment-resistant melanoma patients to immune checkpoint inhibitors (ICIs). In this issue of Cell Host & Microbe, Kim and colleagues extend its utility to other solid tumors, including esophageal and hepatocellular carcinomas.1.

Chemotoxicity and Associated Risk Factors in Colorectal Cancer: A Systematic Review and Meta-Analysis.

BACKGROUND: Colorectal cancer (CRC) patients experience multiple types of chemotoxicity affecting treatment compliance, survival, and quality of life (QOL). Prior research shows clinician-reported chemotoxicity (i.e., grading scales or diagnostic codes) predicts rehospitalization and cancer survival. However, a comprehensive synthesis of clinician-reported chemotoxicity is still lacking. OBJECTIVES: We conducted a systematic review and meta-analysis to determine chemotoxicity's prevalence and risk factors in CRC. METHODS: A systematic search from 2009 to 2024 yielded 30 studies for review, with 25 included in the meta-analysis. RESULTS: Pooled prevalences of overall, non-hematological, and hematological moderate-to-severe toxicities were 45.7%, 39.2%, and 25.3%, respectively. The most common clinician-reported chemotoxicities were gastrointestinal (GI) toxicity (22.9%) and neuropathy or neutropenia (17.9%). Significant risk factors at baseline were malnutritional status, frailty, impaired immune or hepato-renal functions, short telomere lengths, low gut lactobacillus levels, age, female sex, aggressive chemotherapy, and low QOL. Age was associated with neutropenia (ß: -1.44) and GI toxicity (ß:1.85) (p-values < 0.01). Older adults (>65 y.o.) had higher prevalences of overall (OR: 1.14) and GI (OR: 1.65) toxicities, but a lower prevalence of neutropenia (OR: 0.65) than younger adults (p-values < 0.05). CONCLUSIONS: Our findings highlight the importance of closely monitoring and managing chemotoxicity in CRC patients receiving chemotherapy.

Dynamic Human Gut Microbiome and Immune Shifts During an Immersive Psychosocial Therapeutic Program.

Background: Depression is a leading cause of disability worldwide yet its underlying factors, particularly microbial associations, are poorly understood. Methods: We examined the longitudinal interplay between the microbiome and immune system in the context of depression during an immersive psychosocial intervention. 142 multi-omics samples were collected from 52 well-characterized participants before, during, and three months after a nine-day inquiry-based stress reduction program. Results: We found that depression was associated with both an increased presence of putatively pathogenic bacteria and reduced microbial beta-diversity. Following the intervention, we observed reductions in neuroinflammatory cytokines and improvements in several mental health indicators. Interestingly, participants with a Prevotella-dominant microbiome showed milder symptoms when depressed, along with a more resilient microbiome and more favorable inflammatory cytokine profile, including reduced levels of CXCL-1. Conclusions: Our findings reveal a protective link between the Prevotella-dominant microbiome and depression, associated with a less inflammatory environment and moderated symptoms. These insights, coupled with observed improvements in neuroinflammatory markers and mental health from the intervention, highlight potential avenues for microbiome-targeted therapies in depression management.

The Tumor Microbiome as a Predictor of Outcomes in Patients with Metastatic Melanoma Treated with Immune Checkpoint Inhibitors.

Emerging evidence supports the important role of the tumor microbiome in oncogenesis, cancer immune phenotype, cancer progression, and treatment outcomes in many malignancies. In this study, we investigated the metastatic melanoma tumor microbiome and its potential roles in association with clinical outcomes, such as survival, in patients with metastatic disease treated with immune checkpoint inhibitors (ICI). Baseline tumor samples were collected from 71 patients with metastatic melanoma before treatment with ICIs. Bulk RNA sequencing (RNA-seq) was conducted on the formalin-fixed, paraffin-embedded and fresh frozen tumor samples. Durable clinical benefit (primary clinical endpoint) following ICIs was defined as overall survival >24 months and no change to the primary drug regimen (responders). We processed RNA-seq reads to carefully identify exogenous sequences using the {exotic} tool. The age of the 71 patients with metastatic melanoma ranged from 24 to 83 years, 59% were male, and 55% survived >24 months following the initiation of ICI treatment. Exogenous taxa were identified in the tumor RNA-seq, including bacteria, fungi, and viruses. We found differences in gene expression and microbe abundances in immunotherapy-responsive versus nonresponsive tumors. Responders showed significant enrichment of bacteriophages in the phylum Uroviricota, and nonresponders showed enrichment of several bacteria, including Campylobacter jejuni. These microbes correlated with immune-related gene expression signatures. Finally, we found that models for predicting prolonged survival with immunotherapy using both microbe abundances and gene expression outperformed models using either dataset alone. Our findings warrant further investigation and potentially support therapeutic strategies to modify the tumor microbiome in order to improve treatment outcomes with ICIs. SIGNIFICANCE: We analyzed the tumor microbiome and interactions with genes and pathways in metastatic melanoma treated with immunotherapy and identified several microbes associated with immunotherapy response and immune-related gene expression signatures. Machine learning models that combined microbe abundances and gene expression outperformed models using either dataset alone in predicting immunotherapy responses.

The FITNESS study: longitudinal geriatric assessment, treatment toxicity, and biospecimen collection to assess functional disability among older adults with lung cancer.

Introduction: Older adults with chronic disease prioritize functional independence. We aimed to describe the feasibility of capturing functional disability and treatment toxicity among older adults with lung cancer using a longitudinal comprehensive geriatric assessment (CGA) and molecular biomarkers of aging. Methods: This prospective study included adults ≥60 years with any newly diagnosed non-small-cell lung cancer. Participants were recruited from central Ohio (2018-2020). Study assessments included the Cancer and Aging Research Group CGA (CARG-CGA), short physical performance battery (SPPB), and the blessed orientation-memory concentration (BOMC) test at baseline, 3, 6, and 12 months. Activities of daily living (ADLs) and instrumental ADLs (IADLs), quality of life (QoL, PROMIS 10), and treatment toxicity were captured monthly. Stool and blood were collected to characterize the gut microbiome and age-related blood biomarkers. Results: This study enrolled 50 participants with an average age of 71.7 years. Ninety-two percent of participants were Caucasian, 58% were male, and all were non-Hispanic. Most had advanced stage (stage III/IV: 90%; stage I/II: 10%), with adenocarcinoma the predominant histologic subtype (68% vs. 24% squamous). First-line treatments included chemotherapy (44%), immune checkpoint inhibitors (ICIs, 22%), chemotherapy and ICIs (30%), or tyrosine kinase inhibitors (4%). The median baseline CARG toxicity score was 8 (range 2-12). Among patients with treatment-related toxicity (n = 49), 39 (79.6%) cases were mild (grade 1-2), and 10 (20.4%) were moderate to severe (≥ grade 3). Treatment toxicity was greater among those with a CARG score ≥8 (28.0% vs. 13.6%). Higher IADL independence, QoL, and SPPB scores at baseline were positively associated with Candidatus Gastranaerophilales bacterium, Lactobacillus rogosae, and Enterobacteria phage P4. Romboutsia ilealis, Streptococcus, and Lachnoclostridium sp An138 and T cell lag3 and cd8a were associated with worse IADLs, QoL, and SPPB scores at baseline. Discussion: A longitudinal CGA and biomarker collection is feasible among older adults undergoing lung cancer treatment. Gut microbe and T cell gene expression changes correlated with subjective and objective functional status assessments. Future research will test causality in these associations to improve outcomes through novel supportive care interventions to prevent functional disability.

The Tumor Microbiome Reacts to Hypoxia and Can Influence Response to Radiation Treatment in Colorectal Cancer.

Tumor hypoxia has been shown to predict poor patient outcomes in several cancer types, partially because it reduces radiation's ability to kill cells. We hypothesized that some of the clinical effects of hypoxia could also be due to its impact on the tumor microbiome. Therefore, we examined the RNA sequencing data from the Oncology Research Information Exchange Network database of patients with colorectal cancer treated with radiotherapy. We identified microbial RNAs for each tumor and related them to the hypoxic gene expression scores calculated from host mRNA. Our analysis showed that the hypoxia expression score predicted poor patient outcomes and identified tumors enriched with certain microbes such as Fusobacterium nucleatum. The presence of other microbes, such as Fusobacterium canifelinum, predicted poor patient outcomes, suggesting a potential interaction between hypoxia, the microbiome, and radiation response. To experimentally investigate this concept, we implanted CT26 colorectal cancer cells into immune-competent BALB/c and immune-deficient athymic nude mice. After growth, in which tumors passively acquired microbes from the gastrointestinal tract, we harvested tumors, extracted nucleic acids, and sequenced host and microbial RNAs. We stratified tumors based on their hypoxia score and performed a metatranscriptomic analysis of microbial gene expression. In addition to hypoxia-tropic and -phobic microbial populations, analysis of microbial gene expression at the strain level showed expression differences based on the hypoxia score. Thus, hypoxia gene expression scores seem to associate with different microbial populations and elicit an adaptive transcriptional response in intratumoral microbes, potentially influencing clinical outcomes. SIGNIFICANCE: Tumor hypoxia reduces radiotherapy efficacy. In this study, we explored whether some of the clinical effects of hypoxia could be due to interaction with the tumor microbiome. Hypoxic gene expression scores associated with certain microbes and elicited an adaptive transcriptional response in others that could contribute to poor clinical outcomes.

Obesity-associated microbiomes instigate visceral adipose tissue inflammation by recruitment of distinct neutrophils.

Neutrophils are increasingly implicated in chronic inflammation and metabolic disorders. Here, we show that visceral adipose tissue (VAT) from individuals with obesity contains more neutrophils than in those without obesity and is associated with a distinct bacterial community. Exploring the mechanism, we gavaged microbiome-depleted mice with stool from patients with and without obesity during high-fat or normal diet administration. Only mice receiving high-fat diet and stool from subjects with obesity show enrichment of VAT neutrophils, suggesting donor microbiome and recipient diet determine VAT neutrophilia. A rise in pro-inflammatory CD4+ Th1 cells and a drop in immunoregulatory T cells in VAT only follows if there is a transient spike in neutrophils. Human VAT neutrophils exhibit a distinct gene expression pattern that is found in different human tissues, including tumors. VAT neutrophils and bacteria may be a novel therapeutic target for treating inflammatory-driven complications of obesity, including insulin resistance and colon cancer.

Comparative analysis of the tumor microbiome, molecular profiles, and immune cell abundances by HPV status in mucosal head and neck cancers and their impact on survival.

Head and Neck Squamous Cell Carcinoma (HNSCC) comprises a diverse group of tumors with variable treatment response and prognosis. The tumor microenvironment (TME), which includes microbiome and immune cells, can impact outcomes. Here, we sought to relate the presence of specific microbes, gene expression, and tumor immune infiltration using tumor transcriptomics from The Cancer Genome Atlas (TCGA) and associate these with overall survival (OS). RNA sequencing (RNAseq) from HNSCC tumors in TCGA was processed through the exogenous sequences in tumors and immune cells (exotic) pipeline to identify and quantify low-abundance microbes. The detection of the Papillomaviridae family of viruses assessed HPV status. All statistical analyses were performed using R. A total of 499 RNAseq samples from TCGA were analyzed. HPV was detected in 111 samples (22%), most commonly Alphapapillomavirus 9 (90.1%). The presence of Alphapapillomavirus 9 was associated with improved OS [HR = 0.60 (95%CI: 0.40-0.89, p = .01)]. Among other microbes, Yersinia pseudotuberculosis was associated with the worst survival (HR = 3.88; p = .008), while Pseudomonas viridiflava had the best survival (HR = 0.05; p = .036). Microbial species found more abundant in HPV- tumors included several gram-negative anaerobes. HPV- tumors had a significantly higher abundance of M0 (p < .001) and M2 macrophages (p = .035), while HPV+ tumors had more T regulatory cells (p < .001) and CD8+ T-cells (p < .001). We identified microbes in HNSCC tumor samples significantly associated with survival. A greater abundance of certain anaerobic microbes was seen in HPV tumors and pro-tumorigenic macrophages. These findings suggest that TME can be used to predict patient outcomes and may help identify mechanisms of resistance to systemic therapies.

Bridging the Gap from Bench to Bedside: A Call for In Vivo Preclinical Models to Advance Endometrial Cancer and Cervical Cancer Immuno-oncology Research.

Advanced-stage endometrial and cervical cancers are associated with poor outcomes despite contemporary advances in surgical techniques and therapeutics. Recent clinical trial results have led to a shift in the treatment paradigm for both malignancies, in which immunotherapy is now incorporated as the standard of care up front for most patients with advanced endometrial and cervical cancers as the standard of care. Impressive response rates have been observed, but unfortunately, a subset of patients do not benefit from immunotherapy, and survival remains poor. Continued preclinical research and clinical trial development are crucial for our understanding of resistance mechanisms to immunotherapy and maximization of therapeutic efficacy. In this setting, syngeneic models are preferred over xenograft models as they allow for the evaluation of the tumor-immune interaction in an immunocompetent host, most closely mimicking the tumor-immune interaction in patients with cancer. Unfortunately, significant disparities exist about syngeneic models in gynecologic malignancy, in which queries from multiple large bioscience companies confirm no commercial availability of endometrial or cervical cancer syngeneic cell lines. Published data exist about the recent development of several endometrial and cervical cancer syngeneic cell lines, warranting further investigation. Closing the disparity gap for preclinical models in endometrial and cervical cancers will support physician scientists, basic and translational researchers, and clinical trialists who are dedicated to improving outcomes for our patients with advanced disease and poor prognosis.

Longitudinal profiling of the microbiome at four body sites reveals core stability and individualized dynamics during health and disease.

To understand the dynamic interplay between the human microbiome and host during health and disease, we analyzed the microbial composition, temporal dynamics, and associations with host multi-omics, immune, and clinical markers of microbiomes from four body sites in 86 participants over 6 years. We found that microbiome stability and individuality are body-site specific and heavily influenced by the host. The stool and oral microbiome are more stable than the skin and nasal microbiomes, possibly due to their interaction with the host and environment. We identify individual-specific and commonly shared bacterial taxa, with individualized taxa showing greater stability. Interestingly, microbiome dynamics correlate across body sites, suggesting systemic dynamics influenced by host-microbial-environment interactions. Notably, insulin-resistant individuals show altered microbial stability and associations among microbiome, molecular markers, and clinical features, suggesting their disrupted interaction in metabolic disease. Our study offers comprehensive views of multi-site microbial dynamics and their relationship with host health and disease.

Longitudinal profiling of the microbiome at four body sites reveals core stability and individualized dynamics during health and disease.

To understand dynamic interplay between the human microbiome and host during health and disease, we analyzed the microbial composition, temporal dynamics, and associations with host multi-omics, immune and clinical markers of microbiomes from four body sites in 86 participants over six years. We found that microbiome stability and individuality are body-site-specific and heavily influenced by the host. The stool and oral microbiome were more stable than the skin and nasal microbiomes, possibly due to their interaction with the host and environment. Also, we identified individual-specific and commonly shared bacterial taxa, with individualized taxa showing greater stability. Interestingly, microbiome dynamics correlated across body sites, suggesting systemic coordination influenced by host-microbial-environment interactions. Notably, insulin-resistant individuals showed altered microbial stability and associations between microbiome, molecular markers, and clinical features, suggesting their disrupted interaction in metabolic disease. Our study offers comprehensive views of multi-site microbial dynamics and their relationship with host health and disease. Study Highlights: The stability of the human microbiome varies among individuals and body sites.Highly individualized microbial genera are more stable over time.At each of the four body sites, systematic interactions between the environment, the host and bacteria can be detected.Individuals with insulin resistance have lower microbiome stability, a more diversified skin microbiome, and significantly altered host-microbiome interactions.

A Bioinformatics Tool for Identifying Intratumoral Microbes from the ORIEN Dataset.

Evidence supports significant interactions among microbes, immune cells, and tumor cells in at least 10%-20% of human cancers, emphasizing the importance of further investigating these complex relationships. However, the implications and significance of tumor-related microbes remain largely unknown. Studies have demonstrated the critical roles of host microbes in cancer prevention and treatment responses. Understanding interactions between host microbes and cancer can drive cancer diagnosis and microbial therapeutics (bugs as drugs). Computational identification of cancer-specific microbes and their associations is still challenging due to the high dimensionality and high sparsity of intratumoral microbiome data, which requires large datasets containing sufficient event observations to identify relationships, and the interactions within microbial communities, the heterogeneity in microbial composition, and other confounding effects that can lead to spurious associations. To solve these issues, we present a bioinformatics tool, microbial graph attention (MEGA), to identify the microbes most strongly associated with 12 cancer types. We demonstrate its utility on a dataset from a consortium of nine cancer centers in the Oncology Research Information Exchange Network. This package has three unique features: species-sample relations are represented in a heterogeneous graph and learned by a graph attention network; it incorporates metabolic and phylogenetic information to reflect intricate relationships within microbial communities; and it provides multiple functionalities for association interpretations and visualizations. We analyzed 2,704 tumor RNA sequencing samples and MEGA interpreted the tissue-resident microbial signatures of each of 12 cancer types. MEGA can effectively identify cancer-associated microbial signatures and refine their interactions with tumors. SIGNIFICANCE: Studying the tumor microbiome in high-throughput sequencing data is challenging because of the extremely sparse data matrices, heterogeneity, and high likelihood of contamination. We present a new deep learning tool, MEGA, to refine the organisms that interact with tumors.

Associations of frailty with symptoms, and HRQOL in older cancer survivors after cancer treatments: a systematic review and meta-analyses.

PURPOSE: Frailty in older adult cancer survivors after cancer treatments is associated with various health outcomes. However, there is less agreement on how frailty affects symptoms and health-related quality of life (HRQOL). This systematic review and meta-analysis aimed to evaluate the current literature on frailty, symptoms, and HRQOL, as well as the associations of frailty with these factors in older adult cancer survivors with chemotherapy. METHODS: A review was conducted on peer-reviewed publications from 2008 to 2023, using seven electronic databases. Meta-analyses were performed using random effects models to determine pooled effect estimates for frailty prevalence, symptom severity, and HRQOL scores. RESULTS: A total of 26 studies involving older cancer survivors were included in the analysis. Most of these studies were conducted in Western countries and focused on White survivors, particularly those with breast cancer. The mean pooled prevalence of frailty was 43.5%. Among frail survivors, the most common symptoms reported after cancer treatments were pain (36.4%), neuropathy (34.1%), and fatigue (21.3%). Frailty was associated with higher pooled mean symptom severity (B = 1.23, p = 0.046) and lower functional HRQOL (B = - 0.31, p = 0.051, with marginal significance) after cancer treatments. CONCLUSION: Frail older cancer survivors are at high risk of adverse symptoms and poor HRQOL after cancer treatment. Further research on screening for frailty is needed to prevent older adults from developing worse symptoms burden and maintain HRQOL. It is also essential to understand the mechanisms of the associations between frailty, symptoms and HRQOL in this population.

Gut Microbiota Richness and Diversity Track With T Cell Aging in Healthy Adults.

BACKGROUND: This study examined how gut microbiota diversity and richness relate to T cell aging among 96 healthy adults of all ages. It also explored whether these links differed throughout the lifespan. METHODS: Peripheral blood was obtained from 96 study participants (N = 96, aged 21-72) to assess mRNA markers of T cell aging (p16ink4a, p14ARF, B3gat1, Klrg1) and DNA methylation. T cell aging mRNA markers were combined into an aging index, and the Horvath epigenetic clock algorithm was used to calculate epigenetic age based on DNA methylation status of over 500 loci. Participants also collected a stool sample from which the V4 region of the 16S rRNA gene was sequenced to derive the Shannon and Simpson diversity indices, and the total count of observed operational taxonomic units (richness). Models controlled for BMI, comorbidities, sex, dietary quality, smoking status, physical activity, and sleep quality. RESULTS: Lower microbiota richness was associated with higher T cell age based on mRNA markers, but when probing the region of significance, this relationship was only significant among adults 45 years and older (p = .03). Lower Shannon diversity (p = .05) and richness (p = .07) marginally correlated with higher epigenetic age (ie, greater T cell DNA methylation). CONCLUSIONS: Gut microbiota complexity may correspond with the rate of T cell aging, especially in mid-to-late life. These results suggest an interplay between the gut microbiome and immunological aging that warrants further experimental work.

The microbiome and gynecologic cancer: cellular mechanisms and clinical applications.

The microbiome plays a vital function in maintaining human health and homeostasis. Each microbiota has unique characteristics, including those of the gastrointestinal and female reproductive tract. Dysbiosis, or alterations to the composition of the microbial communities, impacts the microbiota-host relationship and is linked to diseases, including cancer. In addition, studies have demonstrated that the microbiota can contribute to a pro-carcinogenic state through altered host immunologic response, modulation of cell proliferation, signaling, gene expression, and dysregulated metabolism of nutrients and hormones.In recent years, the microbiota of the gut and female reproductive tracts have been linked to many diseases, including gynecologic cancers. Numerous pre-clinical and clinical studies have demonstrated that specific bacteria or microbial communities may contribute to the development of gynecologic cancers. Further, the microbiota may also impact the toxicity and efficacy of cancer therapies, including chemotherapy, immunotherapy, and radiation therapy in women with gynecologic malignancies. The microbiota is highly dynamic and may be altered through various mechanisms, including diet, exercise, medications, and fecal microbiota transplantation. This review provides an overview of the current literature detailing the relationship between gynecologic cancers and the microbiota of the female reproductive and gastrointestinal tracts, focusing on mechanisms of carcinogenesis and strategies for modulating the microbiota for cancer prevention and treatment. Advancing our understanding of the complex relationship between the microbiota and gynecologic cancer will provide a novel approach for prevention and therapeutic modulation in the future.

Exogenous Sequences in Tumors and Immune Cells (Exotic): A Tool for Estimating the Microbe Abundances in Tumor RNA-seq Data.

The microbiome affects cancer, from carcinogenesis to response to treatments. New evidence suggests that microbes are also present in many tumors, though the scope of how they affect tumor biology and clinical outcomes is in its early stages. A broad survey of tumor microbiome samples across several independent datasets is needed to identify robust correlations for follow-up testing. We created a tool called {exotic} for "exogenous sequences in tumors and immune cells" to carefully identify the tumor microbiome within RNA sequencing (RNA-seq) datasets. We applied it to samples collected through the Oncology Research Information Exchange Network (ORIEN) and The Cancer Genome Atlas. We showed how the processing removes contaminants and batch effects to yield microbe abundances consistent with non-high-throughput sequencing-based approaches and DNA-amplicon-based measurements of a subset of the same tumors. We sought to establish clinical relevance by correlating the microbe abundances with various clinical and tumor measurements, such as age and tumor hypoxia. This process leveraged the two datasets and raised up only the concordant (significant and in the same direction) associations. We observed associations with survival and clinical variables that are cancer specific and relatively few associations with immune composition. Finally, we explored potential mechanisms by which microbes and tumors may interact using a network-based approach. Alistipes, a common gut commensal, showed the highest network degree centrality and was associated with genes related to metabolism and inflammation. The {exotic} tool can support the discovery of microbes in tumors in a way that leverages the many existing and growing RNA-seq datasets. SIGNIFICANCE: The intrinsic tumor microbiome holds great potential for its ability to predict various aspects of cancer biology and as a target for rational manipulation. Here, we describe a tool to quantify microbes from within tumor RNA-seq and apply it to two independent datasets. We show new associations with clinical variables that justify biomarker uses and more experimentation into the mechanisms by which tumor microbiomes affect cancer outcomes.

The impact of antibiotic and proton pump inhibitor use at the time of adjuvant platinum-based chemotherapy on survival in patients with endometrial cancer.

OBJECTIVE: We sought to assess the impact of antibiotic (ABX) and proton-pump inhibitor (PPI) use on progression-free (PFS) and overall survival (OS) in patients treated with adjuvant platinum-based chemotherapy (PC) for endometrial cancer (EC). METHODS: A retrospective, single-institution cohort study of EC patients treated with ≥four cycles of adjuvant PC following surgical staging from 2014 to 2020. Demographics and clinicopathologic features, including ABX and PPI use, were compared using χ2 and Fisher's exact tests. Univariate and multivariable analyses were performed, and survival outcomes were compared using the log-rank test. RESULTS: Of 325 patients, 95 (29%) received ABX, and 80 (24.6%) received PPI. ABX were associated with decreased 3-year PFS (49.9% vs. 66%; p = 0.0237) but not 3-year OS (68.9% vs. 79.9%; p = 0.0649). ABX targeting gram-positive bacteria were associated with decreased 3-year PFS (21.2% vs. 66.0% vs. 55.4%; p = 0.0038) and 3-year OS (36.5% vs. 79.9% vs. 75.6%; p = 0.0014) compared to no ABX and other ABX, respectively. PPI use was associated with decreased 3-year PFS (46.9% vs. 66.0%; p = 0.0001) and 3-year OS (60.7% vs. 81.9%; p = 0.0041) compared to no PPI. On multivariable regression analysis controlling for confounders including stage, histology, grade, radiation, and co-morbidities, PPI use was independently associated with worse PFS (HR 1.96, 95% CI 1.25-3.08; p = 0.0041) and OS (HR 2.06, 95% CI 1.01-4.18, p = 0.04). CONCLUSION: In this retrospective cohort study, we demonstrate that PPI use is independently associated with worse PFS and OS in patients with EC treated with PC. ABX use was associated with worse PFS on univariate analysis only. There is an unmet need to understand how PPI, ABX, and, potentially, the microbiome impact the effectiveness of chemotherapy in EC patients.

Deciphering the Tumor-Immune-Microbe Interactions in HPV-Negative Head and Neck Cancer.

Patients with human papillomavirus-negative head and neck squamous cell carcinoma (HPV-negative HNSCC) have worse outcomes than HPV-positive HNSCC. In our study, we used a published dataset and investigated the microbes enriched in molecularly classified tumor groups. We showed that microbial signatures could distinguish Hypoxia/Immune phenotypes similar to the gene expression signatures. Furthermore, we identified three highly-correlated microbes with immune processes that are crucial for immunotherapy response. The survival of patients in a molecularly heterogenous group shows significant differences based on the co-abundance of the three microbes. Overall, we present evidence that tumor-associated microbiota are critical components of the tumor ecosystem that may impact tumor microenvironment and immunotherapy response. The results of our study warrant future investigation to experimentally validate the conclusions, which have significant impacts on clinical decision-making, such as treatment selection.