IGL CDR3 Hydropathy and Antigen Chemical Complementarity Associated with Greater Disease-Free Survival in Lung Adenocarcinoma: Implications for Gender Disparities.

With lung cancer remaining a challenging disease, new approaches to biomarker discovery and therapy development are needed. Recent immunogenomics, adaptive immune receptor approaches have indicated that it is very likely that B cells play an important role in mediating better overall outcomes. As such, we assessed physicochemical features of lung adenocarcinoma resident IGL complementarity determining region-3 (CDR3) amino acid (AA) sequences and determined that hydrophobic CDR3 AA sequences were associated with a better disease-free survival (DFS) probability. Further, using a recently developed chemical complementarity scoring algorithm particularly suitable for the evaluation of large patient datasets, we determined that IGL CDR3 chemical complementarity with certain cancer testis antigens was associated with better DFS. Chemical complementarity scores for IGL CDR3-MAGEC1 represented a gender bias, with an overrepresentation of males among the higher IGL-CDR3-CTA complementarity scores that were in turn associated with better DFS (logrank p < 0.065). Overall, this study pointed towards potential biomarkers for prognoses that, in some cases are likely gender-specific; and towards biomarkers for guiding therapy, e.g., IGL-based opportunities for antigen targeting in the lung cancer setting.

Chemical Complementarity of Tumor Resident, Adaptive Immune Receptor CDR3s and Previously Defined Hepatitis C Virus Epitopes Correlates with Improved Outcomes in Hepatocellular Carcinoma.

To better understand how adaptive immune receptors (IRs) in hepatocellular carcinoma (HCC) microenvironments are related to disease outcomes, we employed a chemical complementarity scoring algorithm to quantify electrostatic complementarity between HCC tumor TRB or IGH complementarity-determining region 3 (CDR3) amino acid (AA) sequences and previously characterized hepatitis C virus (HCV) epitopes. High electrostatic complementarity between HCC-resident CDR3s and 12 HCV epitopes was associated with greater survival probabilities, as indicated by two distinct HCC IR CDR3 datasets. Two of the HCV epitopes, HCV*71871 (TRB) and HCV*13458 (IGH), were also determined to represent significantly larger electrostatic CDR3-HCV epitope complementarity in HCV-positive HCC cases, compared with HCV-negative HCC cases, with the CDR3s representing yet a third, independent HCC dataset. Overall, the results indicated the utility of CDR3 AA sequences as biomarkers for HCC patient stratification and as potential guides for the development of therapeutic reagents.

An immunoinformatics assessment of the cancer testis antigen, DDX53, as a potential early esophageal cancer antigen.

T-lymphocytes have been implicated in facilitating a pro-inflammatory, pro-tumorigenic microenvironment that worsens prognosis for esophageal carcinoma (ESCA). In this study, we identified tumor resident, T-cell receptor (TCR) complementarity determining region-3 (CDR3) amino acid sequences and employed an algorithm particularly suited to the big data setting to evaluate TCR CDR3-cancer testis antigen (CTA) chemical complementarities. Chemical complementarity of the ESCA TCR CDR3s and the cancer testis antigen DDX53 represented a disease-free survival (DFS) distinction, whereby the upper fiftieth percentile complementarity group correlated with worse DFS. The high TCR CDR3-DDX53 complementarity group also represented a greater proportion of tumor samples lacking DDX53 expression. These data and analyses raise the question of whether the TCR CDR3-DDX53 chemical complementarity assessment detected an ESCA immune response that selected for DDX53-negative cells?

TRB CDR3 chemical complementarity with HBV epitopes correlates with increased hepatocellular carcinoma, disease-free survival.

The liver is a site of immune privilege, compared with the bladder and skin, for example. To study this attenuation of the immune response in the cancer setting, we compared quantities and features of adaptive immune receptor (IR) recombination reads obtained from hepatocellular carcinoma (HCC) and six other cancers. Of these cancers, HCC had the lowest numbers of IR recombination reads and was the only cancer with a greater number immunoglobulin rather than T-cell receptor recombination reads. To better understand the role of adaptive IRs obtained from the tumor microenvironment in shaping the outcome of HCC cases, we quantified the chemical complementarity between HCC tumor TRB and IGH complementarity determining region-3 (CDR3) amino acid (AA) sequences, and known hepatitis B virus (HBV) epitopes. High chemical complementarity between HCC-resident CDR3s and three HBV epitopes correlated with increased survival probabilities, for two sources of CDR3s representing different CDR3 recovery algorithms. These results suggest the potential of CDR3 AA sequences as biomarkers for HCC patient stratification and as guides for future development of therapeutics.

Chemical Complementarity of Breast Cancer Resident, T-Cell Receptor CDR3 Domains and the Cancer Antigen, ARMC3, is Associated With Higher Levels of Survival and Granzyme Expression.

Introduction: One of the most pressing goals for cancer immunotherapy at this time is the identification of actionable antigens. Methods: This study relies on the following considerations and approaches to identify potential breast cancer antigens: (i) the significant role of the adaptive immune receptor, complementarity determining region-3 (CDR3) in antigen binding, and the existence cancer testis antigens (CTAs); (ii) chemical attractiveness; and (iii) informing the relevance of the integration of items (i) and (ii) with patient outcome and tumor gene expression data. Results: We have assessed CTAs for associations with survival, based on their chemical complementarity with tumor resident T-cell receptor (TCR), CDR3s. Also, we have established gene expression correlations with the high TCR CDR3-CTA chemical complementarities, for Granzyme B, and other immune biomarkers. Conclusions: Overall, for several independent TCR CDR3 breast cancer datasets, the CTA, ARMC3, stood out as a completely novel, candidate antigen based on multiple algorithms with highly consistent approaches. This conclusion was facilitated by use of the recently constructed Adaptive Match web tool.

Electrostatic Complementarities of Glioblastoma-Resident T-Cell Receptors and Cancer Testis Antigens Linked to Poor Outcomes and High Levels of Sphingosine Kinase-2 Expression.

INTRODUCTION: Glioblastoma (GBM) is the most aggressive primary brain tumor in adults. Despite a growing understanding of glioblastoma pathology, the prognosis remains poor. METHODS: In this study, we used a previously extensively benchmarked algorithm to retrieve immune receptor (IR) recombination reads from GBM exome files available from the cancer genome atlas. The T-cell receptor complementarity determining region-3 (CDR3) amino acid sequences that represent the IR recombination reads were assessed and used for the generation of chemical complementarity scores (CSs) that represent potential binding interactions with cancer testis antigens (CTAs), which is an approach particularly suited to a big data setting. RESULTS: The electrostatic CSs representing the TRA and TRB CDR3s and the CTAs, SPAG9, GAGE12E, and GAGE12F, indicated that an increased electrostatic CS was associated with worse disease-free survival (DFS). We also assessed the RNA expression of immune marker genes, which indicated that a high-level expression of SPHK2 and CIITA genes also correlated with high CSs and worse DFS. Furthermore, apoptosis-related gene expression was revealed to be lower when the TCR CDR3-CTA electrostatic CSs were high. CONCLUSION: Adaptive IR recombination reads from exome files have the potential to aid in GBM prognoses and may provide opportunities to detect unproductive immune responses.

Adaptive immune receptor features related to breast cancer tissue in Kenyan patients: high immunoglobulin gene expression and high levels of gamma-delta T-cells.

BACKGROUND: Characterization of the breast cancer (BC) immune response may provide information for a point of intervention, such as application of immunotherapeutic treatments. In this study, we sought to recover and characterize the adaptive immune receptor (IR) recombination reads from genomics files representing Kenyan patients, to better understand the immune response specifically related to those patients. METHODS: We used a previously applied algorithm and software to obtain productive IR recombination reads from cancer and adjacent normal tissue samples representing 22 Kenyan BC patients. RESULTS: From both the RNAseq and exome files, there were significantly more T-cell receptor (TCR) recombination reads recovered from tumor samples compared to marginal tissue samples. Also, the immunoglobulin (IG) genes were expressed at a much higher level than the TCR genes (p-value = 0.0183) in the tumor samples. And, the tumor IG CDR3s consistently represented more positively charged amino acid R-groups, in comparison to the marginal tissue, IG CDR3s. CONCLUSION: For Kenyan patients, a high level of IG expression, representing specific CDR3 chemistries, was associated with BC. These results lay the foundation for studies that could support specific immunotherapeutic interventions for Kenyan BC patients.

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.

Specific TCR V-J gene segment recombinations leading to the identification pan-V-J CDR3s associated with survival distinctions: diffuse large B-cell lymphoma.

In the diffuse large B-cell lymphoma (DLBCL) setting, we examined lymph node biopsy, T-cell receptor features, and the DLBLC patient human leukocyte antigen (HLA) alleles, to provide a basis for assessing survival distinctions represented by the National Cancer Institute Center for Cancer Research (NCICCR) dataset. While previous analyses of other cancer datasets have indicated that specific T-cell receptor (TCR) V or J gene segments, independently, can be associated with a survival distinction, we have here identified V-J recombinations, representing specific V and J gene segments associated with survival distinctions. As specific V-J recombinations represent relatively conserved complementarity determining region-3 (CDR3) amino acid sequences, we assessed the entire DLBCL NCICCR dataset for such conserved CDR3 features. Overall, this approach indicated the opportunity of identifying DLBCL patient subpopulations with TCR CDR3 features, and HLA alleles, with significant survival distinctions, possibly identifying cohorts more likely to benefit from a given immunotherapy.

Extrinsic interactions in the microenvironment in vivo activate an antiapoptotic multidrug-resistant phenotype in CLL.

The Bcl-2 inhibitor venetoclax has yielded exceptional clinical responses in chronic lymphocytic leukemia (CLL). However, de novo resistance can result in failure to achieve negative minimal residual disease and predicts poor treatment outcomes. Consequently, additional proapoptotic drugs, such as inhibitors of Mcl-1 and Bcl-xL, are in development. By profiling antiapoptotic proteins using flow cytometry, we find that leukemic B cells that recently emigrated from the lymph node (CD69+/CXCR4Low) in vivo are enriched for cell clusters simultaneously overexpressing multiple antiapoptotic proteins (Mcl-1High/Bcl-xLHigh/Bcl-2High) in both treated and treatment-naive CLL patients. These cells exhibited antiapoptotic resistance to multiple BH-domain antagonists, including inhibitors of Bcl-2, Mcl-1, and Bcl-xL, when tested as single agents in a flow cytometry-based functional assay. Antiapoptotic multidrug resistance declines ex vivo, consistent with resistance being generated in vivo by extrinsic microenvironmental interactions. Surviving "persister" cells in patients undergoing venetoclax treatment are enriched for CLL cells displaying the functional and molecular properties of microenvironmentally induced multidrug resistance. Overcoming this resistance required simultaneous inhibition of multiple antiapoptotic proteins, with potential for unwanted toxicities. Using a drug screen performed using patient peripheral blood mononuclear cells cultured in an ex vivo microenvironment model, we identify novel venetoclax drug combinations that induce selective cytotoxicity in multidrug-resistant CLL cells. Thus, we demonstrate that antiapoptotic multidrug-resistant CLL cells exist in patients de novo and show that these cells persist during proapoptotic treatment, such as venetoclax. We validate clinically actionable approaches to selectively deplete this reservoir in patients.

Chemical complementarity between immune receptors and cancer mutants, independent of antigen presentation protein binding, is associated with increased survival rates.

Uterine cancer has been associated with a T-cell immune response that leads to increased survival. Therefore, we used several bioinformatics approaches to explore specific interactions between T-cell receptor (TCR) and tumor mutant peptide sequences. Using endometrioid uterine cancer exome files from the The Cancer Genome Atlas database, we obtained tumor resident V-J recombinations for the T-Cell Receptor alpha gene (TRA). The charged-based, chemical complementarity for each patient's LRP2 or TTN mutant amino acids (AAs) and the recovered, TRA complementarity determining region-3 (CDR3) sequences was calculated, allowing a division of patients into complementary and noncomplementary groups. Complementary groups with TTN mutants had increased disease-free survival and increased expression of complement genes. Furthermore, the survival distinction based on CDR3-mutant peptide complementarity was independent of programmatically assessed HLA class II binding and was not observable based on the CDR3 AA chemical features alone. The above approach provides a potential, highly efficient method for identifying TCR targets in uterine cancer and may aid in the development of novel prognostic tools.