High Level Immunoglobulin Gene Expression and Reduced Intra-tumoral Bacteria Associated With the Transition from Initial to Progressive Diffuse Intrinsic Pontine Glioma.

BACKGROUND/AIM: In the past decade, diffuse intrinsic pontine glioma (DIPG), the most common childhood brainstem glioma, has benefitted from an increase in tissue-based research because of improved biopsy collection techniques. However, the adaptive immune receptor (IR) features represented by tumor material and tumor infiltrating lymphocytes have remained poorly understood. MATERIALS AND METHODS: Herein, we characterized the adaptive immune parameters of DIPG through the recovery of IR recombination reads from RNAseq files representing initial and progressive DIPG samples. RESULTS: An elevated level of immunoglobulin gene expression in the progressive DIPG sample files and a reduced number of bacterial sequencing read recoveries in comparison to RNAseq files representing the initial form of DIPG, was found. Furthermore, the RNAseq files representing both initial and progressive DIPG samples had significant numbers of reads representing Cutibacterium acnes, a bacterium previously linked to prostate cancer development. Results also indicated an opportunity to distinguish overall survival probabilities based on IGL complementarity determining region-3 amino acid sequence physicochemical parameters. CONCLUSION: Genomics analyses allow for a better understanding of adaptive IR features and bacterial infections in the DIPG setting.

Bacterial Sequencing Reads in Blood Exome Files from Melanoma and Cervical Cancer Patients are Associated with Cancer Recurrence.

Bacteremia poses great risk for morbidity and mortality for immunocompromised cancer patients. Although the presence of bacteria within solid tumors is gaining greater attention, few studies have analyzed species of bacteria in the blood and their effect on cancer clinical outcomes. Using the Kraken 2 taxonomic profiling tool, we classified bacteria present in blood and primary tumors of cervical cancer and melanoma cases. The Cancer Genome Atlas (TCGA) melanoma blood exome files with Pseudomonas species were found to represent a worse disease-free survival (DFS) probability, while a worse overall survival (OS) result was evidenced for both the TCGA and Moffitt Cancer Center melanoma datasets. Cervical cancer cases with reads representing the Bradyrhizobium genus and Bradyrhizobium sp. BTAi1 found in blood and tumor exome files were found to have lower DFS. Additionally, reduced DFS and OS were observed for cervical cancer cases positive for Bacteroides species including Bacteroides fragilis. This study provides novel evidence and a novel approach for indicating that bacteria in blood is associated with cancer recurrence. These findings may guide the development of more efficient prognostic and screening tools related to bacterial blood infections of melanoma and cervical cancer patients.