Predictors of thrombosis during VV ECMO: an analysis of 9809 patients from the ELSO registry

Venovenous extracorporeal membrane oxygenation (VV-ECMO) is a life-saving therapy for critically ill patients, but it carries an increased risk of thrombosis due to blood interacting with non-physiological surfaces. While the relationship between clinical variables and thrombosis remains unclear, our study aimed to identify which factors are most predictive of thrombosis. The Extracorporeal Life Support Organization Registry was queried to obtain a cohort of VV-ECMO patients aged 18 years and older from 2015 to 2019. Patients who were over 80-years-old, at the extremes of weight, who received less than 24 h of ECMO, multiple rounds of ECMO, or had missing data were excluded. Multivariate logistic regression modeling was used to assess predictors of thrombosis and mortality. A total of 9809 patients were included in the analysis, with a mean age of 47.1 ± 15.1 years and an average ECMO run time of 305 ± 353 h. Thrombosis occurred in 19.9% of the cohort, with circuit thrombosis (8.6%) and membrane lung failure (6.1%) being the most common. Multivariate analysis showed that ECMO runs over 14 days (OR: 2.62, P < 0.001) and pregnancy-related complications (OR: 1.79, P = 0.004) were associated with an increased risk of thrombosis. Risk factors for circuit thrombosis included incremental unit increases in the pump flow rate at 24 h (OR: 1.07 [1.00-1.14], P = 0.044) and specific cannulation sites. Increased body weight (OR: 1.02 [1.00-1.04], P = 0.026) and increased duration on ECMO (OR: 3.82 [3.12-4.71], P < 0.001) were predictive of membrane lung failure. Additionally, patients with thrombosis were at increased likelihood of in-hospital mortality (OR: 1.52, P < 0.001). This study identified multiple thrombotic risk factors in VV-ECMO, suggesting that future studies investigating the impact of pregnancy associated complications and ECMO flow rate on hemostasis would be illuminating.

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.

Specific Intratumor Bacteria Genera and TRG Recombinations Associated with Greater Survival Probability in Alimentary Tract Cancers

INTRODUCTION

There remains a lack of knowledge regarding the effects of the intratumor microbiome on the tumor immune milieu. We aimed to investigate whether intratumoral bacterial RNA sequence abundance in gastric and esophageal cancers is associated with T-cell infiltrate features.

METHODS

We assessed cases representing the stomach adenocarcinoma (STAD) and esophageal cancer (ESCA) databases of The Cancer Genome Atlas. RNA-seq data estimating intratumoral bacterial abundance was obtained from publicly available sources. TCR recombination reads were mined from exome files. Survival models were generated using the lifelines python package.

RESULTS

Increasing levels of the Klebsiella genus were associated with a better OS probability (hazard ratio, 0.5), via a Cox proportional hazards model. The higher Klebsiella abundance was associated with a significantly increased overall (p = 0.0001) and disease-specific survival (p = 0.0289) probability for the STAD dataset. Cases representing the upper 50th percentile of Klebsiella abundance also represented a significantly increased recovery of TRG and TRD recombination reads (p = 0.00192). Analogous results were found for the Aquincola genus in ESCA.

CONCLUSIONS

This is the first report of associations between low biomass bacterial samples from primary tumor samples with patient survival and with an increased gamma-delta T cell infiltrate. Results indicate that the gamma-delta T cells potentially play a role in the dynamics of the bacterial infiltration of primary tumors of the alimentary tract.

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?

Blood-based T cell receptor anti-viral CDR3s are associated with worse overall survival for neuroblastoma

With the advent of large collections of adaptive immune receptor recombination reads representing cancer, there is the opportunity to further investigate the adaptive immune response to viruses in the cancer setting. This is a particularly important goal due to longstanding but still not well-resolved questions about viral etiologies in cancer and viral infections as comorbidities. In this report, we assessed the T cell receptor complementarity determining region-3 (CDR3) amino acid (AA) sequences, for blood-sourced TCRs from neuroblastoma (NBL) cases, for exact AA sequence matches to previously identified anti-viral TCR CDR3 AA sequences. Results indicated the presence of anti-viral TCR CDR3 AA sequences in the NBL blood samples highly significantly correlated with worse overall survival. Furthermore, the TCR CDR3 AA sequences demonstrating chemical complementarity to many cytomegalovirus antigens represented cases with a worse outcome, including cases where such CDR3s were obtained from tumor samples. Overall, these results indicate a significant need for, and provide a novel strategy for assessing viral infection complications in NBL patients.

The presence of intratumoral Porphyromonas gingivalis correlates with a previously defined pancreatic adenocarcinoma, immune cell expression phenotype and with tumor resident, adaptive immune receptor features

The association between pancreatic adenocarcinoma (PAAD) and the pancreatic microbiome is not fully understood, although bacteria may decrease the effectiveness of chemotherapy and lead to anti-apoptotic, pro-inflammatory microenvironments. To better understand the relationship between the PAAD microbiome and the microenvironment, we identified Porphyromonas gingivalis-positive PAAD samples and found a strong association between intratumoral P. gingivalis and: (i) an immune cell gene expression phenotype previously defined by others as gene program 7; and (ii) recovery of immunoglobulin recombination, sequencing reads. We applied a novel chemical complementarity scoring algorithm, suitable for a big data setting, and determined that the previously established P. gingivalis antigen, rpgB had a reduced chemical complementarity with T-cell receptor (TCR) complementarity-determining region-3 amino acid sequences recovered from PAAD samples with P. gingivalis in comparison to TCR-rpgB chemical complementarity represented by the PAAD samples that lacked P. gingivalis. This finding strengthens the existing body of evidence correlating P. gingivalis with PAAD, which may have implications for the treatment and prognosis of patients. Furthermore, demonstrating the correlation of P. gingivalis and gene program 7 raises the question of whether P. gingivalis infection is responsible for the gene program 7 subdivision of PAAD?

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.

Exploiting big data survival information to unify risk-stratification related, adaptive immune receptor parameters for multiple myeloma

With the improvement of treatment options, multiple myeloma related life expectancy has been prolonged, but the disease remains largely incurable. Immunotherapy is a growing field that shows promise in advancements for treatment, and recent work has demonstrated an opportunity to use immune receptor, complementarity determining region-3 (CDR3)-candidate antigen chemical complementarity scores to identify survival distinctions among subgroups of patients. Here, we have applied the complementarity scoring algorithm to identify multiple myeloma related, CDR3-cancer testis antigen (CTA) relationships associated with survival distinctions. Furthermore, we have overlapped these immune receptor features with a previous study that showed a dramatic survival distinction based on T-cell receptor, V- and J-gene segment usage, HLA allele combinations, whereby 100% of the patients in certain combination groups had no mortality related to multiple myeloma, during the study period. This overlap evaluation was consistent with the idea that there are likely considerable constraints on productive TRB-antigen-HLA combinations but more flexibility, and unpredictability, for the TRA-antigen-HLA combinations. Also, the approaches in this reported indicated the potential importance of the CTA, IGSF11, as a multiple myeloma antigen, an antigen previously, independently considered as a vaccine candidate in other settings.

Chemical features of melanoma tumor resident TRG CDR3s associated with better survival probabilities

We assessed the T-cell receptor gamma (TRG) recombination reads from the cancer genome atlas melanoma tumor exome files and the TRG recombination reads from an independent, melanoma exome file dataset, from the Moffitt Cancer Center. TRG complementarity determining region-3 (CDR3) amino acid (AA) sequences were assessed for chemical complementarity to cancer testis antigens, with such complementarity for FAM133A and CRISP2 associated with better survival probabilities for both datasets. These results, along with related TRG CDR3 AA chemical feature assessments provided in this report, have indicated opportunities for melanoma patient stratifications based on the recovery of TRG recombination reads from both tumor and blood samples, and the results may point towards novel, effective melanoma antigens.

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.

A Bioinformatics Assessment Indicating Better Outcomes With Breast Cancer Resident, Immunoglobulin CDR3-MMP2 Binding

BACKGROUND/AIM

The recombination of V, D, and J immunoglobulin (IG) gene segments leads to many variations in the amino acids (AAs) encoded at that site, the complementarity determining region-3 (CDR3). Thus, cancer patients may have varying degrees of CDR3 AA binding specificity for cancer proteases, for example, matrix metalloproteinase 2 (MMP2). MMP2 in breast cancer has been found to contribute to metastasis and is used as a marker for tumor staging. Thus, this report evaluated the tumor resident, patient specific IG CDR3 binding affinities to cancer proteases to test the hypothesis that greater binding affinities would be associated with a better outcome.

MATERIALS AND METHODS

Using two independent bioinformatics tools, we evaluated the IG CDR3-MMP2 binding affinities throughout the cancer genome atlas breast cancer (TCGA-BRCA) dataset.

RESULTS

Results indicated that the better the CDR3-MMP2 binding, the better the survival probability. An analogous evaluation for four other proteases, including calpain-1 and thermolysin, displayed no such associations with survival probabilities.

CONCLUSION

This study is consistent with the possibility that patient IG-cancer protease interactions could impact outcomes and raises the question of whether therapeutic antibody targeting of MMP2 would reduce breast cancer mediated tissue destruction and breast cancer mortality rates.

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.

TCR CDR3-antigen chemical complementarity associated with poor ovarian cancer outcomes: A vestigial immune response to early cancer antigens?

Ovarian cancer continues to present significant challenges for early detection and treatment, indicating a need for novel approaches to improve disease outcomes. In this report, we applied a previously described algorithm for detecting chemical complementarity between candidate cancer antigens and complementarity determining region-3 (CDR3) amino acid sequences from tumor resident T-cell receptors. Current literature indicates an association between high CDR3-cancer antigen complementarity and improved survival outcomes. For example, high CDR3-BRAF electrostatic complementarity is associated with a better melanoma outcome. However, such CDR3-cancer antigen chemical complementarity in ovarian cancer was largely associated with worse outcomes. Specifically, high CDR3-MAGEB4 and CDR3-TDRD1 electrostatic complementarity was associated with lower ovarian cancer disease free survival (DFS). Additionally, high CDR3-MAGEB4 and CDR3-TDRD1 electrostatic complementarity was associated with decreased MAGEB4/TDRD1 gene expression and gene copy numbers, consistent with a selection against ovarian cancer cells expressing these antigens. However, when TDRD1 was split into fragments, high CDR3-TDRD1 hydrophobicity complementarity, for a specific TDRD1 fragment, was associated with increased DFS and higher immune marker expression levels. This dichotomy highlights the myriad of opportunities to establish risk stratifications and to identify potential, actionable cancer antigens using immunogenomic parameters.

TRB CDR3-cancer testis antigen chemical complementarity scoring for identifying productive immune responses in renal cell carcinoma

BACKGROUND

Immunogenomics approaches to the characterization of renal cell carcinoma (RCC) have helped to better our understanding of the features of RCC immune dysfunction. However, much is still unknown with regard to specific immune interactions and their impact in the tumor microenvironment.

OBJECTIVE

This study applied chemical complementarity scoring for the TRB complementarity determining region-3 (CDR3) amino acid sequences and cancer testis antigens (CTAs) to determine whether such complementarity correlated with survival and the expression of immune marker genes.

METHODS

TRB recombination reads from RCC tumor samples from RNAseq files obtained from two separate databases, Moffitt Cancer Center and The Cancer Genome Atlas (TCGA), were evaluated. Chemical complementarity scores (CSs) were calculated for TRB CDR3-CTA pairs and survival assessments based on those CSs were performed.

RESULTS

Moffitt Cancer Center and TCGA cases representing the upper 50th percentile of chemical CSs for TRB CDR3 amino acid sequences and the CTA POTEA were found to be associated with a better overall survival (OS) Also, greater tumor RNA expression of multiple immune signature genes, including granzyme A, granzyme B, and interferon-gamma were correlated with the higher chemical CSs.

CONCLUSIONS

These results indicate that TRB CDR3-CTA chemical complementarity scoring may be useful in distinguishing RCC cases with a productive, anti-tumor immune response from cases where basic immune parameter assessments are inconsistent with a productive immune response.

Chemical complementarity between tumor resident, T-cell receptor CDR3s and MAGEA3/6 correlates with increased melanoma survival: Potential relevance to MAGE vaccine auto-reactivity

Cancer testis antigens have been of interest as possible targets for cancer immunotherapies. To better understand the opportunities for the use of such immunotherapy targets, we used a chemical complementarity scoring algorithm and an original web tool to establish aspects of electrostatic complementarity of the CTAs, MAGEA3 and MAGEA6, with melanoma specimen resident, T-cell receptor (TCR) complementarity determining region 3 (CDR3) amino acid sequences. Greater electrostatic complementarity between T-cell receptor CDR3 and tumor CTAs MAGEA3/6 was associated with a greater probability of overall survival, for both the cancer genome atlas and Moffitt Cancer Center samples; and was associated with high levels of T-cell cytotoxicity-related gene expression. Most importantly, this approach allowed for the highly efficient screening of specific segments of the MAGEA3/6 antigens which indicated that certain MAGE segments would have either more or less risk of auto-reactivity. In sum, the chemical complementarity algorithm, and its efficient application via the web tool, adaptivematch.com, offers a convenient opportunity to identify likely parameters important for immunotherapy considerations and melanoma patient risk stratifications.

Tumor Resident, B-Cell Receptor Chemical Characteristics Associated with Better Overall Survival for Neuroblastoma

Pediatric neuroblastoma (NBL) is one of the most common pediatric cancers, and it can often be aggressive. Genetic and demographic factors can correlate with the severity of NBL, but the variations in the B-cell receptors (BCRs) or immunoglobulin proteins present in the NBL tumors, and their relationships to survival, are not well understood. BCRs contain variations in their complementary determining region-3 (CDR3s) amino acid sequences, due to variable recombinations of the V- and J-gene segments. Accordingly, these variations in CDR3s may represent different antigen interactions and thereby different survival probabilities. Thus, we mined the TARGET project, NBL tumor RNAseq files for BCR recombination reads. Evaluations of the physicochemical properties of IGK, IGL, and IGH CDR3s from these tumors pointed to properties of IGK and IGL in particular as associated with survival distinctions, based on several independent bioinformatics approaches, including a novel homology grouping approach facilitated by a recently developed web tool, adaptivematch.com. In conclusion, tumor resident BCR chemical features are likely useful for better risk stratification and for guiding therapy, and the availability of a user-friendly web tool will likely facilitate using BCR chemical features to meet those goals.

Immunogenomics Parameters for Patient Stratification in Alzheimer's Disease

BACKGROUND

Despite the fact that only modest adaptive immune system related approaches to treating Alzheimer's disease (AD) are available, an immunogenomics approach to the study of AD has not yet substantially advanced.

OBJECTIVE

Thus, we sought to better understand adaptive immune receptor chemical features in the AD setting.

METHODS

We characterized T-cell receptor alpha (TRA) complementarity determining region-3 (CDR3) physicochemical features and identified TRA CDR3 homology groups, represented by TRA recombination reads extracted from 2,665 AD-related, blood- and brain-derived exome files.

RESULTS

We found that a higher isoelectric value for the brain TRA CDR3s was associated with a higher (clinically worse) Braak stage and that a number of TRA CDR3 chemical homology groups, in particular representing bloodborne TRA CDR3s, were associated with higher or lower Braak stages. Lastly, greater chemical complementarity of both blood- and brain-derived TRA CDR3s and tau, based on a recently described CDR3-candidate antigen chemical complementarity scoring process (https://adaptivematch.com), was associated with higher Braak stages.

CONCLUSION

Overall, the data reported here raise the questions of (a) whether progression of AD is facilitated by the adaptive immune response to tau; and (b) whether assessment of such an anti-tau immune response could potentially serve as a basis for adaptive immune receptor related, AD risk stratification?

Chemical complementarity between immune receptor CDR3s and candidate cancer antigens correlating with reduced survival: evidence for outcome mitigation with corticosteroid treatments

The evaluation of physicochemical characteristics of extensive adaptive immune receptor (IR) recombination sequence collections has led to the discovery of many correlations of those sequences and a variety of diseases, including cancer. In the cancer setting, these evaluations have recently focused on the adaptive IR, complementarity determining region-3 (CDR3) amino acid (AA) sequences, which play a major role in antigen binding. For example, the chemical complementarities of the tumor resident, CDR3 AA sequences and the BRAFV600E mutant, common in melanoma, have proved informative with regard to outcomes. Many of these evaluations led to the conclusion that a high affinity match, efficiently, algorithmically designated as a high chemical complementarity score (CS) for the patient specific, IR CDR3 AA sequences and the cancer antigens, correlated with improved survival outcomes. In this report, the complementarity scoring algorithms were used to investigate the opposite phenomenon, high complementarity chemistry between CRD3 AAs and cancer antigens that correlated with a worse survival, an approach that revealed potential risk stratification biomarkers for lung adenocarcinoma, lung squamous carcinoma, and likely other cancer types. Most importantly, analyses suggested that high IR CDR3 AA-candidate antigen CS, low overall survival results for low grade glioma were mitigated by neoadjuvant corticosteroid treatments. Overall, the analyses of this report, coupled with earlier work establishing the CS approach for identifying likely good outcomes, have the potential to distinguish patients who will benefit from (i) immune activating or (ii) immune augmenting or (iii) even immunosuppressive treatment strategies.Communicated by Ramaswamy H. Sarma.

A comparison of immune receptor recombination databases sourced from tumour exome or RNAseq files: Verifications of immunological distinctions between primary and metastatic melanoma

It became apparent several years ago that RNAseq and exome files prepared from tissue could be mined for adaptive immune receptor (IR) recombinations, which has given extra value to datasets originally intended for gene expression or mutation studies. For example, recovery of IR recombination reads from tumour specimen genomics files can correlate with survival rates. In particular, many benchmarking processes have been applied to the two sets of the IR recombination reads obtained from the cancer genome atlas files, but these two sets have never been directly compared. Here we show that both sets largely agree regarding several parameters. For example, recovery of TRB recombination reads from both WXS and RNAseq files representing metastatic melanoma was associated with a better outcome (p < .0004 in both cases); and T-cell receptor recombination read recovery, for both genomics file types, associated very strongly with T-cell gene expression markers. However, the use of CDR3 chemical features for survival distinctions was not consistent. This topic, and the surprising result that both datasets indicated that primary melanoma with recovery of IR recombination reads, in stark contrast to metastatic melanoma, represents a worse outcome, are discussed.

High-throughput, sliding-window algorithm for assessing chemical complementarity between immune receptor CDR3 domains and cancer mutant peptides: TRG-PIK3CA interactions and breast cancer

Physicochemical assessments of a vast accumulation of adaptive immune receptor (IR) recombinations have led to correlations of those properties with sub-divisions of various diseases. In the cancer setting, such assessments, particularly for the complementarity determining region-3 (CDR3) immune receptor domain, have been used to establish chemical complementarity matches to mutant amino acids (AA). These matches, in some cases, over very large numbers of tumor samples, have correlated with survival and gene expression distinctions. For example, in melanoma, electrostatic charge based, T-cell receptor CDR3-DNAH9 mutant AA complementarity represents better survival over multiple datasets that represent tumor tissue, T-cell receptor CDR3s. In this report, the complementarity approach has been expanded to include a more comprehensive representation of the interaction of T-cell receptor CDR3s and mutant AAs by incorporating the impact of the wild-type AAs surrounding the mutant AA. This "sliding window" approach was benchmarked against two large datasets of empirically determined CDR3-epitope pairs; showed more significant patient subdivisions; revealed a novel, TRG CDR3-mutant PIK3CA linkage in breast cancer; and was particularly suited to use with big data collections using only modest and widely-available processors. Thus, the algorithm should support more rapid and convenient indications (or prescreens) of CDR3-mutant peptide interactions for more focused studies and more efficient development of patient immunology-related prognostic tools and therapies.

Electrostatic Complementarity of T-Cell Receptor-Alpha CDR3 Domains and Mutant Amino Acids Is Associated with Better Survival Rates for Sarcomas

While sarcoma immunology has advanced with regard to basic, and even some applied topics, this disease has not been subject to more recent immunogenomics approaches. Thus, we assessed the immune receptor recombinations available from the cancer genome atlas (TCGA) sarcoma database via tumor sample exome and RNASeq files. Results indicated that recovery of T-cell receptor-alpha recombination reads (TRA) correlated with a better survival rate, with the expression of T-cell biomarkers, and with tumor sample apoptosis signatures consistent with the longer patient survival times. Furthermore, samples representing TRA complementarity determining region-3 (CDR3) net charge per residue (NCPR) based complementarity with the corresponding sarcoma mutanome had a better survival rate, and more granzyme expression, than samples lacking such complementarity. By specifically using RNASeq-recovered TRA CDR3s and related NCPR assessments, three genes, TP53, ATRX, and RB1, were identified as being key components of the mutanome-based complementarity. Thus, these genes may represent key immune system targets for soft tissue sarcomas. Also, several key results from above were reproduced with a pediatric osteosarcoma dataset, work that led to identification of MUC6 mutations as potentially linked to a strong immune response. In sum, TRA CDR3s are likely to be important prognostic indicators, and possibly a beginning tool for immunotherapy development strategies, for adult and pediatric sarcomas.

Specific HLA alleles, paired with TCR V- and J-gene segment usage, link to distinct multiple myeloma survival rates

Multiple myeloma (MM) immunogenomics studies related to T-cell characterizations and involving large patient sets have been lacking, particularly in comparison to solid tumor types. Thus, we evaluated (i) HLA alleles, and (ii) T-Cell Receptor (TCR) V- and J-gene segment, HLA allele combinations, based on TCR recombinations in blood samples, for their potential associations with overall survival distinctions among an MM cohort. Two HLA alleles, and seven TCR V- or J-gene segment, HLA allele combinations were found to be associated with distinct overall survival rates. For examples, HLA-C*08:02, and the TRAV19, HLA-C*07:01 combination, were found to be associated with negative outcomes. In addition, anti-cytomegalovirus immune receptor sequences, from blood samples, were found to be associated with a positive outcome (p = 0.012, n = 278). These data, and other related immunogenomics data, indicate a potential opportunity to use personal immunogenetics parameters as guides to prognosis and therapies.

Chemical features of blood-borne TRG CDR3s associated with an increased overall survival in breast cancer

PURPOSE

Immunogenomics and earlier, pioneering studies, particularly by Whiteside and colleagues, have indicated a positive role for B-cells in breast cancer, as well as a positive role for gamma-delta T-cells. However, these studies have been completely limited to assessing breast cancer tumor tissue.

METHODS AND RESULTS

Our analyses here has shown that blood-borne T-cell receptor gamma (TRG) chain sequences were associated with greater overall survival, of particular note due to the comparative longevity of primary breast cancer patients, whereby assessments of disease-free, but rarely overall survival parameters are possible. Additional immunogenomics approaches narrowed the overall survival correlations to specific, TRG complementarity determining region-3, amino acid (AA) sequence chemical features, independently of many common, confounding variables in the breast cancer setting, such as estrogen or progesterone receptor status.

CONCLUSIONS

These results are discussed in the context of patient age and with regard to potential antigenic targets, based on the chemistry of the TRG CDR3 AA sequences associated with the higher survival rates.

Abstract B12: Potential neoantigen release and increased lymphocyte activity is facilitated by matrix metalloproteinase-dependent cleavage of mutant matrisome peptides in cutaneous melanoma

Introduction: Proteases in the cancer microenvironment have been studied for decades, with a general conclusion that such proteases facilitate the spread of cancer, although there is some controversy regrading that conclusion in later stages of cancer development. More recently, a very large collection of data regarding mutant amino acids in the potential substrates of the cancer microenvironment has become available.

Methods: To better understand the potential impact of these mutant amino acids on protease function and cancer progression, we established a bioinformatics approach to assessing the impact of melanoma mutants, among a previously defined set of ECM structural proteins, on MMP2, a protease extensively associated with melanoma in terms of both protease sensitivity and MHC class I binding using original software. Additionally, T-cell receptor TRα and TRβ recombinations were bioinformatically obtained using whole-exome sequencing data from 479 melanoma tumor samples.

Results: Tumor samples with mutant amino acids adjacent to ECM structural protein, MMP2-cleavage sites represented a better survival rate and a larger proportion of mutant peptides with high HLA class I binding affinities, particularly in comparison to melanoma samples lacking a T-cell infiltrate. Furthermore, even better MHC class I binders, as a group, were identified among the sample representing ECM structural proteins mutants not adjacent to MMP2 sensitive sites and evincing a relatively poor survival rate.

Conclusion: Overall, this analysis suggested that MMP2 has the capacity of freeing mutant peptides that could facilitate an antitumor response and a better survival rate, and this analysis has the potential of resolving some of the controversy surrounding the role of cancer proteases in cancer progression.

Citation Format: Saif Zaman, Boris I. Chobrutskiy, Jay S. Patel, Blake M. Callahan, Moody Mihyu, Andrea Diviney, Wei Lue Tong, George Blanck. Potential neoantigen release and increased lymphocyte activity is facilitated by matrix metalloproteinase-dependent cleavage of mutant matrisome peptides in cutaneous melanoma [abstract]. In: Proceedings of the AACR Special Conference on Melanoma: From Biology to Target; 2019 Jan 15-18; Houston, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(19 Suppl):Abstract nr B12.

TRBV and TRBJ usage, when paired with specific HLA alleles, associates with distinct head and neck cancer survival rates

Common or dominant, T-cell receptor (TCR), V and J usage, in combination with particular human leukocyte antigen (HLA) alleles, has been associated with differing outcomes in viral infections, autoimmunity, and more recently, in cancer. Cervical cancer in particular represents the most dramatic series of distinctions of outcomes associated with differing combinations of dominant V or J usage and HLA alleles, possibly because of the strong association of cervical cancer with human papilloma virus (HPV), in turn leading to a likely molecular consistency in the mechanism of HPV antigen presentation. Thus, we considered assessing TRB V and J usage, HLA allele combinations, for their associations with survival rates and related data, in the cancer genome atlas head and neck cancer dataset. We obtained the TRB VDJ recombination reads from both the blood and tumor exome files and determined the V and J identities. We then established case ID (patient) subsets of V or J usage, HLA alleles, and determined, for example, that the TRBJ2-7, HLA-B*40:01 combination was associated with a better disease free survival rate than were either the TRBJ1-3, HLA-DPB1*03:01 or the TRBJ2-1, HLA-DPB1*02:01 combinations. Furthermore, these analyses led to the conclusion that TRBJ1-5 usage, and the HLA-C*08:02 and HLA-DRB1*03:01 alleles, had independent associations with distinct overall survival rates. In sum, the results suggest that dominant V or J usage, HLA allele combinations, and in certain cases, dominant V or J usage independently of HLA, could be useful in prognosis and in guiding immunotherapies.

Antiviral T Cell Receptor Complementarity Determining Region-3 Sequences Are Associated with a Worse Cancer Outcome: A Pancancer Analysis

Human papilloma virus has a clearly demonstrated role in cervical and head and neck cancers, but viral etiology for other solid tumors is less well understood. To expand this area of research, we obtained and analyzed the immune receptor recombinations available from both blood and tumor samples, through mining of exome files produced from those sources, for 32 cancer types represented by the cancer genome atlas (TCGA). Among TCGA data sets, the recovery frequency for antiviral complementarity determining region-3 sequences (CDR3s), for T cell receptor-alpha and T cell receptor-beta, ranged from 0% to 21% of the patients, for the different cancer types, with breast, lung, pancreatic, and thymus cancers representing the highest of that range, particularly for tumor tissue resident T cells. In several cases, recovery of the antiviral CDR3s associated with distinct survival rates, and in all of these cases, the recovery of an antiviral CDR3 associated with a worse survival rate.

B-cell Receptor Recombinations in Lung Adenocarcinoma Exome Files Correlate With a Higher Overall Survival Rate

BACKGROUND/AIM

While there has been a rapid development in genomic data mining approaches for T-cell receptor recombinations (TcR), less emphasis has been placed on B-cell receptor (BcR) recombinations.

MATERIALS AND METHODS

We obtained lung cancer exome files from the cancer genome atlas (TCGA) and mined the files for TcR and BcR recombination reads.

RESULTS

There was a robust detection of BcR light chain recombination reads in lung adenocarcinoma (TCGA-LUAD) samples, and there was a correlation between the detection of light chain recombination reads and a more favorable outcome. This result was supported by analyses of the expression of B-cell markers as indicated by LUAD RNASeq files.

CONCLUSION

BcR and TcR recombination reads recovered from LUAD WXS files, either alone or in combination with the human leukocyte antigen (HLA) type, are likely to have prognostic value.

A scoring system for the electrostatic complementarities of T-cell receptors and cancer-mutant amino acids: multi-cancer analyses of associated survival rates

The anti-tumor immune response is considered to be due to the T-cell receptor (TCR) binding to tumor antigens, which can be either wild-type, early stem cell proteins, presumably foreign to a developed immune system; or mutant peptides, foreign to the immune system because of a mutant amino acid (aa) or otherwise somatically altered aa sequence. Recently, very large numbers of TCR complementarity-determining region-3 (CDR3) aa sequences obtained from tumor specimens have become available. We developed a novel algorithm for assessing the complementarity of tumor mutant peptides and TCR CDR3s, based on the retrieval of TCR CDR3 aa sequences from both tumor specimen and patient blood exomes and by using an automated process of assessing CDR3 and mutant aa electrical charges. Results indicated many instances where high electrostatic complementarity was associated with a higher survival rate. In particular, our approach led to the identification of specific genes contributing significantly to the complementary, TCR CDR3-mutant aa. These results suggest a novel approach to tumor immunoscoring and may lead to the identification of high-priority neo-antigen, peptide vaccines; or to the identification of ex vivo stimulants of tumor-infiltrating lymphocytes.

Aberrant Epidermal Growth Factor Receptor RNA Splice Products Are Among the Most Frequent Somatic Alterations in Clear Cell Renal Cell Carcinoma and Are Associated with a Poor Response to Immunotherapy

BACKGROUND

Accumulating evidence suggests that alternative RNA splicing has an important role in cancer development and progression by driving the expression of a diverse array of RNA and protein isoforms from a handful of genes. However, our understanding of the clinical significance of cancer-specific RNA splicing in renal cell carcinoma (RCC) is limited.

OBJECTIVE

To characterize and validate a novel oncogene RNA splicing event discovered in patients with RCC and to correlate expression with clinical outcomes.

DESIGN, SETTING, AND PARTICIPANTS

Using DNA and RNA sequencing, we identified a novel epidermal growth factor receptor (EGFR) splicing alteration (EGFR_pr20CTF) in RCC tumor tissue.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We confirmed the frequency and specificity of the EGFR_pr20CTF variant by analyzing cohorts of patients from our institution (n = 699) and The Cancer Genome Atlas (TCGA; n = 832). Furthermore, we analyzed its expression in tumor tissue and a human kidney cancer cell line using reverse transcriptase-polymerase chain reaction. Variant expression was also correlated with survival and response to systemic therapy.

RESULTS AND LIMITATIONS

EGFR_pr20CTF expression was identified in 71.7% (n = 71/99) of patients with RCC in our institutional cohort and in 56.7% (n = 279/492) of patients in the TCGA cohort. EGFR_pr20CTF was found to be specific to clear cell renal cell carcinoma (ccRCC), occurring in <0.2% of non-RCC tumors (n = 2/1091). High levels of EGFR_pr20CTF correlated with lower survival at 48 mo following immunotherapy (p = 0.036). The average survival in patients with high EGFR_pr20CTF expression was <16 mo.

CONCLUSIONS

The EGFR_pr20CTF RNA splice variant occurs frequently, is specific to patients with advanced ccRCC, and is associated with a poor response to immunotherapy.

PATIENT SUMMARY

Cancer-specific RNA alternative splicing may portend a poor prognosis in patients with advanced clear cell renal cell carcinoma. Further investigation will help clarify whether EGFR_pr20CTF can be used as a biomarker for this patient population.

TRAV gene segments further away from the TRAJ gene segment cluster appear more commonly in human tumor and blood samples

We considered the possibility that the greater the distance between an immune receptor V and J, the more likely the V usage. Such a hypothesis is supported by results from mouse experiments. And, such a hypothesis is consistent with the fundamental nature of recombination and genomic distance: the further the distance, the greater the chance of a DNA break. Thus, we exploited the vast dataset of V and J recombination reads available for the human TRA gene, particularly from cancer and blood specimens, to assess the frequency of TRAV usage with respect to distance from the TRAJ cluster. Results indicated that, indeed, over the entire TRAV cluster, there is a greater chance of V usage the further the distance from the J cluster. These results do not address causation, and are not consistent for certain individual V gene segments, but the results do indicate that overall, the larger the distance between the V and J gene segment cluster, the more likely the appearance of at least a subset of TRAV segments, particularly among tumor infiltrating lymphocytes. With a similar approach, the distal TRAV gene segments were also found to be more commonly associated with a subset of distal TRAJ segments. These results have implications for restrictions on the apparent TRA repertoire in disease settings.

An age-based, RNA expression paradigm for survival biomarker identification for pediatric neuroblastoma and acute lymphoblastic leukemia

Background

Pediatric cancer survival rates overall have been improving, but neuroblastoma (NBL) and acute lymphoblastic leukemia (ALL), two of the more prevalent pediatric cancers, remain particularly challenging. One issue not yet fully addressed is distinctions attributable to age of diagnosis.

Methods

In this report, we verified a survival difference based on diagnostic age for both pediatric NBL and pediatric ALL datasets, with younger patients surviving longer for both diseases. We identified several gene expression markers that correlated with age, along a continuum, and then used a series of age-independent survival metrics to filter these initial correlations.

Results

For pediatric NBL, we identified 2 genes that are expressed at a higher level in lower surviving patients with an older diagnostic age; and 4 genes that are expressed at a higher level in longer surviving patients with a younger diagnostic age. For pediatric ALL, we identified 3 genes expressed at a higher level in lower surviving patients with an older diagnostic age; and 17 genes expressed at a higher level in longer surviving patients with a younger diagnostic age.

Conclusions

This process implicated pan-chromosome effects for chromosomes 11 and 17 in NBL; and for the X chromosome in ALL.

Electronic supplementary material

The online version of this article (10.1186/s12935-019-0790-5) contains supplementary material, which is available to authorized users.

Matrix-Metalloprotease Resistant Mucin-16 (MUC16) Peptide Mutants Represent a Worse Lung Adenocarcinoma Outcome

PURPOSE

The relationship of lung adenocarcinoma (LUAD)-specific proteases and the mutant profile of cytoskeletal and extracellular matrix proteins (CECMPs) are examined.

EXPERIMENTAL DESIGN

Mutant CECMPs are assessed with an automated application of a protease binding, amino acid-based, scoring database.

RESULTS

MUC16 (Human Genome Organization symbol for mucin-16 gene) mutants in particular are, more often than not, resistant to matrix-metalloproteases (MMPs) commonly secreted by LUAD cells, and LUAD cases representing the MUC16, MMP resistant mutants have a worse outcome. Similar results are obtained for MUC16 mutants resistant to cathepsins, also commonly secreted by LUAD cells. Analyses also show that MUC16, MMP resistant peptide mutants have greater binding affinities to HLA-A and HLA-B when compared to MUC16, MMP nonresistant peptide mutants.

CONCLUSION

These results provide a potential, novel biomarker for lung cancer progression, in particular, protease resistant MUC16 peptides; and suggest a possible mechanism of immune escape entailing the reduction of mutant peptides available for HLA class I binding.

MAPT (Tau) expression is a biomarker for an increased rate of survival for low‑grade glioma

The association of MAPT (Tau) with various tauopathies and other neurological disorders has long been established. However, the role of microtubule‑associated protein Tau (MAPT) expression in brain cancer is largely unknown. To determine whether MAPT expression is related to low‑grade glioma (LGG) survival rates, RNASeq data representing samples from the Cancer Genome Atlas (TCGA) were assessed. Results revealed that high expression of the MAPT gene is very strongly associated with increased overall and disease‑free survival in LGG but not in breast cancer or melanoma. No such association was apparent for either amyloid precursor protein or α‑synuclein gene expression. The expression levels of particular apoptosis‑ and pro‑proliferative‑effector genes were consistent with the Tau‑associated increased survival rates. It has been well established that the Tau protein plays a neurodegenerative role, and in this study we identified, for the first time, a potential cell apoptosis function that Tau may play in cancers of the central nervous system.

MAPT (Tau) expression is a biomarker for an increased rate of survival in pediatric neuroblastoma

Although the impact of MAPT (Tau) expression has been well documented for neuronal cells in the context of tauopathies and neurodegenerative diseases, the impact and role of Tau expression in cancer, and specifically cancers of neuronal origin, is in its infancy. To determine the correlation between MAPT expression and survival in pediatric neuroblastoma, MAPT gene expression for samples from the TARGET pediatric neuroblastoma dataset was assessed. Initial analyses indicated that increased MAPT expression correlated with increased overall survival in neuroblastoma but not in ovarian cancer. Expression of apoptosis- and proliferation-effector genes in the neuroblastoma samples was consistent with the MAPT related survival result. Furthermore, we determined that higher neuroblastoma expression of APP also associated with neurodegeneration, correlated with better neuroblastoma survival rates. In sum, Gene expression associated with neuronal degenerative diseases was associated with a better neuroblastoma outcome. Abbreviations: ALS: Amyotrophic Lateral Sclerosis; APP: Amyloid Precursor Protein gene; CASP3: Caspase 3 gene; CASP9: Caspase 9 gene; H2AFX: H2A histone family, member X gene; HIST1H2AL: Histone H2A type 1 gene; HIST1H2BK: Histone H2B type 1-K gene; HIST1H3J: Histone H3J gene; HIST1H4B: Histone H4B gene; HIST2H2BE: Histone H2B type 2-E gene; HUGO: human genome organization; KM: Kaplan-Meier survival curve; MAPT: Tau gene; OV: Ovarian cancer; SNCA: alpha-syneculin gene; TARDBP: Transactive response DNA binding protein 43 kDa; TCGA: the cancer genome atlas.

Mutant cytoskeletal and ECM peptides sensitive to the ST14 protease are associated with a worse outcome for glioblastoma multiforme

We previously identified a set of the most frequently mutated cytoskeleton- and extracellular matrix-related proteins (CECMPs) in numerous cancer datasets. In this report, we used a bioinformatics approach to assess the impact of amino acid (AA) substitutions on the sensitivity of CECMPs to the ST14 protease (matriptase I), a transmembrane serine protease previously implicated in cancer development. Results indicated that AA substitutions in glioblastoma multiforme (GBM) CECMPs are skewed toward increased resistance to the ST14 protease, in comparison to the wild-type peptide sequence. Furthermore, the protease resistant AA substitutions represent relatively high binding affinities to HLA class I proteins, when assessing the binding specificities using HLA class I alleles matched to the source of the mutant AA. Moreover, samples representing AA substitutions that increased protease sensitivity also represented reduced overall and disease-free survival periods for patients with glioblastoma. To assess tumor specimen immunogenicity, we identified T-cell receptor (TCR) V(D)J recombinations in GBM exome files. The overlap between ST14 protease sensitive mutant barcodes and the TCR V(D)J recombination read positive barcodes represented significantly reduced survival.