Gene Expression Profile Signature Research Articles

Association of RNA-sequencing signatures with clinical outcomes of pembrolizumab + chemotherapy in patients with metastatic nonsquamous non–small cell lung cancer (NSCLC) enrolled in the phase 2 KEYNOTE-782 trial.

8578 Background: KEYNOTE-782 (NCT03664024) was a single-arm phase 2 study designed to assess possible biomarkers of response (objective response rate [ORR]) to first-line pembrolizumab + chemotherapy (pemetrexed + carboplatin or cisplatin) in patients with previously untreated metastatic nonsquamous NSCLC. Herein, we examined relationships between the T-cell–inflamed gene expression profile (TcellinfGEP) and other tumor microenvironment consensus signatures and efficacy of pembrolizumab + chemotherapy in an exploratory analysis of KEYNOTE-782. Methods: All patients were to receive pembrolizumab 200 mg Q3W, pemetrexed 500 mg/m2 Q3W, and 4 Q3W cycles of carboplatin AUC 5 mg/mL/min or cisplatin 75 mg/m2. Using tumor samples, RNA sequencing was used to measure expression of the TcellinfGEP and 10 non-TcellinfGEP signatures (angiogenesis, gMDSC, glycolysis, hypoxia, mMDSC, MYC, proliferation, RAS, stromal/EMT/TGFβ, and WNT). The association between each signature and clinical outcomes was analyzed using logistic regression (ORR) and Cox proportional hazards regression (progression-free survival [PFS] and overall survival [OS]); the prespecified significance level was α = 0.05 for TcellinfGEP (hypothesized positive association) and α = 0.10 for non-TcellinfGEP signatures (hypothesized negative associations). The clinical utility of TcellinfGEP was descriptively assessed using a prespecified cutoff of the first tertile. The clinical database cutoff was November 5, 2021. Results: Of 117 patients enrolled, 69 (59.0%) had evaluable RNA-sequencing data. TcellinfGEP was not associated with ORR ( P = 0.183), PFS ( P = 0.071), or OS ( P = 0.142); the area under the receiver operating characteristic curve for discriminating response was 0.56 (95% CI, 0.42-0.71). None of the 10 non-TcellinfGEP consensus signatures showed a statistically significant association with clinical outcomes after adjusting for TcellinfGEP (multiplicity adjusted P > 0.10). ORR and median PFS were comparable in the TcellinfGEP low and nonlow subgroups; there was a trend towards longer OS in the nonlow subgroup (Table). Conclusions: In this exploratory analysis of patients with metastatic nonsquamous NSCLC, none of the RNA-sequencing signatures evaluated were associated with clinical outcomes of pembrolizumab + chemotherapy. There was little evidence of clinical utility of TcellinfGEP when evaluated as a dichotomous variable. Data support the use of pembrolizumab + chemotherapy as first-line therapy for patients with nonsquamous NSCLC regardless of consensus signature status. Clinical trial information: NCT03664024 . [Table: see text]

Navigating High-Risk and Ultrahigh-Risk Multiple Myeloma: Challenges and Emerging Strategies.

Despite significant improvement in the outcomes of patients with newly diagnosed multiple myeloma (NDMM) with novel therapies, there is still an underserved high-risk (HR) population that experiences early disease progression and death. With the median survival crossing 10 years, we defined ultrahigh-risk (uHR)MM as MM leading to death within 24-36 months of diagnosis and HRMM as MM leading to death within 36-60 months. Several features have emerged as markers of uHRMM: the co-occurrence of two or more high-risk cytogenetic abnormalities, extramedullary disease, plasma cell leukemia and a high-risk gene expression profiling signature. The heterogeneous risk definition across trials, the few trials available designed for HR patients, and the small HR subgroups in all-comers trials make it difficult to generate recommendations with high levels of evidence. Nevertheless, regardless of treatment administered, several studies consistently showed that achieving and maintaining measurable residual disease negativity is now considered the main factor able to mitigate the adverse prognosis related to baseline features. For fit patients with HR transplant-eligible (TE) NDMM, quadruplet induction/consolidation treatment with anti-CD38 monoclonal antibodies, immunomodulatory agents, proteasome inhibitors and dexamethasone, and autologous stem-cell transplant and maintenance with, if available, at least a doublet combination could be considered the option of choice. For non-TE NDMM, considering the recent data generated and carefully reviewing those upcoming, quadruplet treatment consisting of anti-CD38 monoclonal antibodies, immunomodulatory agents, proteasome inhibitors, and dexamethasone should also be considered. Future trials integrating BCMA-directed novel generation immunotherapies hold great potential for further advancing the treatment landscape in all NDMM patients with HR disease.

Gene Expression Profiling Reveals Two Overarching Types of Anaplastic Large Cell Lymphoma with Distinct Targetable Biology: An L.L.M.P.P. Study

Background: Anaplastic large cell lymphomas (ALCLs) are CD30-positive T-cell lymphomas that share pathologic features but differ in clinical presentation, outcome, and molecular features. The World Health Organization (WHO) and International Consensus Classification (ICC) classify ALCLs by presence or absence of ALK rearrangements (R) and clinical presentation (systemic, cutaneous [c], or breast implant-associated [BIA]). ICC, but not WHO, recognizes DUSP22-R as defining a new genetic subtype of ALK- ALCL. The classifications otherwise do not reflect additional molecular heterogeneity in genetics (e.g., TP63-R) or therapeutic vulnerabilities (e.g., JAK-STAT3 pathway activation). Methods: ALCLs (N=689) underwent expert consensus review (WHO/ICC) through the Lymphoma/Leukemia Molecular Profiling Project (LLMPP). All cases also underwent genetic subtyping (ALK, DUSP22, TP63, and triple-negative [TN]) using fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC), as well as IHC for phospho-STAT3 Tyr705 (pSTAT3). RNAseq was performed and evaluable in 393 cases; the remaining cases had insufficient tissue, tumor content, RNA yield or quality, and/or sequencing data quality. Sequenced and non-sequenced sub-cohorts had similar demographics and subtype distribution. Results: Unsupervised gene expression profiling (GEP) identified 2 main molecular types of ALCL. Type I ALCLs predominantly included ALK+ ALCLs, BIA-ALCLs, and a subset of TN ALCLs (designated TN-I), whereas Type II ALCLs predominantly included ALCLs with DUSP22-R, TP63-R, or both (double-hit; DH), and the remaining TN ALCLs (TN-II). Type I ALCLs were strongly associated with pSTAT3 expression (74.2±26.4% positive malignant cells vs 9.9±22.7% for Type II; P<0.0001). An independently derived pSTAT3 staining threshold of 30% assigned Type I vs II with 91% accuracy. A third cluster of ALCLs, mostly cALCL, showed an epithelial GEP signature rather than a lymphoma signature; these cases were assigned to Types I or II based on pSTAT3 IHC. Distinct sub-signatures were identified for ALK+, DUSP22-R, TP63-R, and BIA ALCL (Fig. 1), but not ALK- ALCL or cALCL. Gene set enrichment analysis showed Type I ALCLs to be enriched for JAK-STAT3 signaling genes (normalized enrichment score [NES], 2.22; FDR<0.0001) and related pathways, such as TNFα-NFκB signaling (NES, 2.21; FDR<0.0001). In contrast, Type II ALCLs were enriched for cell cycle, DNA repair, epigenetic, and metabolic pathway genes, but not for major tyrosine kinase-mediated signaling pathway genes. Enriched epigenetic pathways included chromatin modifying enzymes (NES, -1.86; FDR=0.002) and histone methylation (NES, -1.71; FDR=0.002). EZH2 was the most overexpressed gene in Type II ALCLs (fold-change, 7.74; FDR=8.84×10 -306). At the protein level, EZH2 IHC H-scores were 275±45 in Type II and 168±70 in Type I ALCLs (P<0.0001); H3K27me3 H-scores were 170±81 and 76±63, respectively (P<0.001). The top metabolic gene set involved cholesterol biosynthesis (NES, -1.88; FDR=0.002). Overall survival (OS) data were available in 257 systemic ALCL patients (145 sequenced and 112 non-sequenced; cALCL and BIA-ALCL were excluded). Non-sequenced TN ALCLs were assigned to TN-I or TN-II using pSTAT3 IHC. The results supported earlier data indicating favorable prognosis of DUSP22-R ALCL (5 y OS, 95%) and ALK+ ALCL (87%), intermediate prognosis of TN ALCL (TN-I, 52% and TN-II, 38%; P=NS), and poor prognosis of TP63-R/DH ALCL (0%)(P<0.0001; Fig. 2). Conclusions: Two overarching molecular types of ALCL exist, predominantly associated with the presence (Type I) or absence (Type II) of the JAK-STAT3 signaling program. Distinct GEP signatures exist for ALK+ ALCL and BIA-ALCL (predominantly Type I), and DUSP22-R ALCL and TP63-R ALCL (predominantly Type II). TN ALCLs lacking ALK-R, DUSP22-R, and TP63-R can be stratified into TN-I and TN-II subtypes. pSTAT3 IHC has >90% accuracy as a surrogate for GEP-based subtyping. ALK- ALCL and cALCL cluster by molecular subtype rather than by defining GEP signatures. Type II ALCLs are enriched for targetable epigenetic and metabolic pathways, including EZH2/histone methylation and cholesterol biosynthesis. This molecular classification is diagnostically, prognostically, and potentially therapeutically relevant, and can be applied using FISH and IHC in routine practice and in the clinical trial setting.

Refining Diagnostic Subtypes of Peripheral T-Cell Lymphoma Using a Multiparameter Approach

Peripheral T-cell lymphoma (PTCL) encompasses a diverse group of post-thymic lymphomas, with ~40% of cases not further classifiable and designated as PTCL-not otherwise specified (PTCL-NOS). Two molecular prognostic subtypes of PTCL-NOS, PTCL-TBX21 and PTCL-GATA3, were identified through gene expression profiling (GEP). A subset of PTCL-NOS with T-follicular helper (TFH) differentiation was subsequently categorized as nodal PTCL with TFH phenotype (PTCL-TFH), also known in current classifications as nodal PTCL-TFH, NOS, or TFH lymphoma, NOS. However, the boundary between PTCL-NOS and PTCL-TFH remains poorly defined. To refine these subtypes, 101 PTCL-NOS with centralized pathology review and extensive immunophenotyping by immunohistochemistry (IHC) using 22 antibodies, digital GEP (nCounter, NanoString Inc) (n= 70), and RNA sequencing (n= 73) were included in this study. IHC was used to identify PTCL-TFH cases (those with strong expression of more than two TFH markers); the remaining patients were classified as PTCL-GATA3 and PTCL-TBX21 using pre-defined GEP signatures. Cases were reclassified into PTCL-NOS (n= 63) and PTCL-TFH (n= 38), with PTCL-NOS subclassified into PTCL-GATA3 (n= 22; 34%) and PTCL-TBX21 (n= 41; 66%) and showing significant differences in OS (p<0.001). PTCL-GATA3 was characterized by medium to large transformed cells (average= 90%, 70-100%) and had minimal tumor microenvironment (TME) (TME-poor: 100%). In contrast, PTCL-TBX21 was more heterogeneous, associated with pleomorphic cells in a polymorphous background (TME-rich: 78%), including Lennert lymphoma-like cases (22%). mRNA and CIBERSORT analysis substantiated the findings and identified a subset enriched in cytotoxic features in the PTCL-TBX21 subtype. IHC indicated that PTCL-GATA3 cases were CD4+/CD8- (83%) or CD4-/CD8- (17%) and lacked expression of CD8 or cytotoxic markers compared to PTCL-TBX21 (p<0.01). PTCL-GATA3 showed significantly higher expression of LEF1 (average= 80%), Ki67 (80%), and MYC (25%) than PTCL-TBX21 (25%, 30%, <5%, respectively, p<0.01). mRNA and protein expression of these biomarkers showed a significant positive correlation (r=0.5, p<0.001), and expectedly higher mRNA expression of LEF1 and MYC was observed in the PTCL-GATA3 versus PTCL-TBX21 (p<0.05). Strong expression of CD30 (>50% of cells) was only seen in PTCL-GATA3 cases. EBER positivity, found only in rare background cells, was not significantly different (18% of PTCL-GATA3 vs. 12% of PTCL-TBX21). Within PTCL-TBX21, we identified cytotoxic and non-cytotoxic subsets with divergent morphological, phenotypic, and clinical findings. The cytotoxic PTCL-TBX21 exhibited an activated cytotoxic phenotype (23/25, 96%), denoted by TIA1 and granzyme-B and/or perforin expression. Extranodal involvement and single-cell apoptosis were observed in 17% and 45% of the cytotoxic cases, respectively, but absent in non-cytotoxic PTCL-TBX21 cases. A trend towards higher Ki67 expression (average= 40% vs. 20%, p= 0.08) was seen in the cytotoxic subgroup. In contrast, the non-cytotoxic PTCL-TBX21 was associated with a CD4+/CD8- phenotype and higher ICOS expression (average= 30%) and CCR4 (60%) compared to the cytotoxic PTCL-TBX21 (p= 0.001). PTCL-TFH cases showed a CD4+/CD8- phenotype (90%) and rarely a CD4-/CD8- phenotype (10%). While a subset of PTCL-TFH cases had AITL-like features such as numerous clear cells and/or prominent vasculature (31% of cases), which were not seen in the other subgroups, the remaining cases exhibited morphology that was indistinguishable from other PTLC-NOS cases including sheets of transformed cells or pleomorphic cells in a polymorphous background. Morphologically, PTCL-TFH cases, like PTCL-TBX21 were associated with a rich TME (TME-rich: 75%). CIBERSORT analysis showed enrichment of plasma cells (p<0.01) in PTCL-TFH, compared to PTCL-TBX21, and validated by morphology (30% of cases vs. 5%). Expression of one TFH marker was frequent in some PTCL-NOS cases (PTCL-GATA3= 41% of cases, PTCL-TBX21-non cytotoxic= 47%, PTCL-TBX21-cytotoxic= 5%). Conclusion: Our comprehensive evaluation underscores the importance of integrating morphology, immunophenotyping, and GEP in achieving an accurate diagnosis, potentially leading to more tailored treatment strategies for PTCL. Correlation with pending whole-exome sequencing studies will be provided at the time of presentation.

Tumor-Infiltrating Normal B Lymphocytes Have Remarkable Prognostic Effects and Are Crucial for Antitumor Immune Responses in Diffuse Large B-Cell Lymphoma

Introduction: In recent years, increasing evidence suggests an important role of tumor-infiltrating B lymphocytes (TIL-Bs) in cancer immunity. In various types of solid tumors, high density of TIL-Bs and presence of mature tertiary lymphoid structures consistently correlate with better prognosis and response to immune checkpoint blockade therapies. Diffuse large B-cell lymphoma (DLBCL) is a type of aggressive lymphoma arising from mature B cells. TIL-Bs have been identified in DLBCL based on single-cell gene-expression data in several previous studies, but their prognostic significance in DLBCL is unknown. In this study, we determined the clinical significance of TIL-B abundance and investigated the potential underlying mechanisms. Patients and Methods: This abstract includes a discovery study in which we distinguished TIL-Bs from malignant B-cells by immunoglobulin gene (IG) clonotype analysis and a validation study using flow cytometry. In the discovery study, a molecularly well-characterized DLBCL cohort assembled by the International DLBCL R-CHOP Consortium Program was analyzed. DNA samples from DLBCL patients were sequenced by high-throughput ultra-deep sequencing assays using multiplexed forward and reverse primers. Based on the IG heavy chain (IGH) sequencing results, malignant B-cell and TIL-B VDJ clonotypes were identified for 138 patients, and the frequencies and numbers of TIL-B clonotypes in individual sequence repertoires were calculated. In 79 DLBCL cases, a DJ-only sequence was predominant and no productive VDJ sequences met the criteria for diagnostic sequences. Total frequencies of productive VDJ sequences in the sequence repertoires were then used to access high and low TIL-B frequencies. TIL-B frequencies were also evaluated by IG light chain clonotypes for these 217 patients and additional 52 patients. The TIL-B frequencies were correlated with patient survival, gene-expression profiling (GEP) data GSE31312, and frequencies of DLBCL-infiltrating immune cells quantified by fluorescent multiplex immunohistochemistry (mIHC). To validate the prognostic significance of TIL-B frequencies, we assembled a validation cohort of 94 DLBCL patients treated at Duke University Medical Center. TIL-Bs in tissues were quantified by flow cytometry immunophenotyping. Ratios of TIL-Bs to abnormal B cells were assessed for prognostic effects. Results: First, we found thathigh frequencies of TIL-Bs and clonotypic diversity were associated with significantly favorable prognostic effects in 138 DLBCL patients with their malignant B-cell IGH-VDJ clonotypes identified (Figure A). The prognostic effects of TIL-Bs outweighed those of the germinal center B-cell-like/activated B-cell-like classification (Figure B). Second, patients with high frequencies of TIL-Bs compared with those without had significant upregulation of immune response genes by GEP (Figure C), higher CD4 T cell infiltration quantified by fluorescent mIHC (Figure D), and enrichment of EcoTyper-defined specific cell states, including significantly increased frequencies of B cell state S2 (pre-memory), CD4 T cell state S3 (naïve), follicular helper T cell state S3, and endothelial cell state S3, whereas lower frequencies of B cell state S5 (plasmablast) and follicular helper T cell state S1. Third, high TIL-B abundance in 79 ‘DJ-only’ clonotype cases and additional 52 cases assessed by light chain clonotype analysis showed similar favorable prognostic effects and associations with upregulated immune gene expression and CD4 T cell infiltration. Fourth, the identified GEP signatures, prominent with genes involved in T-dependent B cell activation and T cell activation and differentiation, showed significant prognostic effects in two GEO datasets. Fifth, TIL-B abundance showed significant prognostic effects in DLBCL cases infiltrated with T-cells in both the discovery study (Figure E) and validation study (Figure F, flow cytometry cohort). Conclusions: TIL-B frequencies and clonotypic diversity have remarkable prognostic and biological effects in DLBCL, which has significant implications for developing novel therapeutic strategies. Our study identified a new prognostic biomarker in DLBCL and an important player in anti-lymphoma immune responses, providing a new point of view to analyze the tumor biology in aggressive B-cell lymphoma and precisely identify prognostic determinants.

Tumor-Infiltrating Normal B Cells Revealed by Immunoglobulin Repertoire Clonotype Analysis Are Highly Prognostic and Crucial for Antitumor Immune Responses in DLBCL.

Tumor-infiltrating B lymphocytes (TIL-B) have demonstrated prognostic and predictive significance in solid cancers. In this study, we aimed to distinguish TIL-Bs from malignant B-cells in diffuse large B-cell lymphoma (DLBCL) and determine the clinical and biological significance. A total of 269 patients with de novo DLBCL from the International DLBCL R-CHOP Consortium Program were studied. Ultra-deep sequencing of the immunoglobulin genes was performed to determine B-cell clonotypes. The frequencies and numbers of TIL-B clonotypes in individual repertoires were correlated with patient survival, gene expression profiling (GEP) data, and frequencies of DLBCL-infiltrating immune cells quantified by fluorescent multiplex IHC at single-cell resolution. TIL-B abundance, evaluated by frequencies of normal B-cell clonotypes in the immunoglobulin repertoires, remarkably showed positive associations with significantly better survival of patients in our sequenced cohorts. DLBCLs with high versus low TIL-B abundance displayed distinct GEP signatures, increased pre-memory B-cell state and naïve CD4 T-cell state fractions, and higher CD4+ T-cell infiltration. TIL-B frequency, as a new biomarker in DLBCL, outperformed the germinal center (GC) B-cell-like/activated B-cell-like classification and TIL-T frequency. The identified TIL-B-high GEP signature, including genes upregulated during T-dependent B-cell activation and those highly expressed in normal GC B cells and T cells, showed significant favorable prognostic effects in several external validation cohorts. TIL-B frequency is a significant prognostic factor in DLBCL and plays a crucial role in antitumor immune responses. This study provides novel insights into the prognostic determinants in DLBCL and TIL-B functions with important therapeutic implications.

Transcriptomic analysis of cutaneous squamous cell carcinoma reveals a multigene prognostic signature associated with metastasis

Metastasis of cutaneous squamous cell carcinoma (cSCC) is uncommon. Current staging methods are reported to have sub-optimal performances in metastasis prediction. Accurate identification of patients with tumors at high risk of metastasis would have a significant impact on management. To develop a robust and validated gene expression profile signature for predicting primary cSCC metastatic risk using an unbiased whole transcriptome discovery-driven approach. Archival formalin-fixed paraffin-embedded primary cSCC with perilesional normal tissue from 237 immunocompetent patients (151 nonmetastasizing and 86 metastasizing) were collected retrospectively from four centers. TempO-seq was used to probe the whole transcriptome and machine learning algorithms were applied to derive predictive signatures, with a 3:1 split for training and testing datasets. A 20-gene prognostic model was developed and validated, with an accuracy of 86.0%, sensitivity of 85.7%, specificity of 86.1%, and positive predictive value of 78.3% in the testing set, providing more stable, accurate prediction than pathological staging systems. A linear predictor was also developed, significantly correlating with metastatic risk. This was a retrospective 4-center study and larger prospective multicenter studies are now required. The 20-gene signature prediction is accurate, with the potential to be incorporated into clinical workflows for cSCC.

The expression profiles of signature genes from CD103+LAG3+ tumour-infiltrating lymphocyte subsets predict breast cancer survival.

Tumour-infiltrating lymphocytes (TILs), including T and B cells, have been demonstrated to be associated with tumour progression. However, the different subpopulations of TILs and their roles in breast cancer remain poorly understood. Large-scale analysis using multiomics data could uncover potential mechanisms and provide promising biomarkers for predicting immunotherapy response. Single-cell transcriptome data for breast cancer samples were analysed to identify unique TIL subsets. Based on the expression profiles of marker genes in these subsets, a TIL-related prognostic model was developed by univariate and multivariate Cox analyses and LASSO regression for the TCGA training cohort containing 1089 breast cancer patients. Multiplex immunohistochemistry was used to confirm the presence of TIL subsets in breast cancer samples. The model was validated with a large-scale transcriptomic dataset for 3619 breast cancer patients, including the METABRIC cohort, six chemotherapy transcriptomic cohorts, and two immunotherapy transcriptomic cohorts. We identified two TIL subsets with high expression of CD103 and LAG3 (CD103+LAG3+), including a CD8+ T-cell subset and a B-cell subset. Based on the expression profiles of marker genes in these two subpopulations, we further developed a CD103+LAG3+ TIL-related prognostic model (CLTRP) based on CXCL13 and BIRC3 genes for predicting the prognosis of breast cancer patients. CLTRP-low patients had a better prognosis than CLTRP-high patients. The comprehensive results showed that a low CLTRP score was associated with a high TP53 mutation rate, high infiltration of CD8 T cells, helper T cells, and CD4 T cells, high sensitivity to chemotherapeutic drugs, and a good response to immunotherapy. In contrast, a high CLTRP score was correlated with a low TP53 mutation rate, high infiltration of M0 and M2 macrophages, low sensitivity to chemotherapeutic drugs, and a poor response to immunotherapy. Our present study showed that the CLTRP score is a promising biomarker for distinguishing prognosis, drug sensitivity, molecular and immune characteristics, and immunotherapy outcomes in breast cancer patients. The CLTRP could serve as a valuable tool for clinical decision making regarding immunotherapy.

Immune desert in MMR-deficient tumors predicts poor responsiveness of immune checkpoint inhibition.

Although many efforts have been devoted to identify biomarkers to predict the responsiveness of immune checkpoint inhibitors, including expression of programmed death-ligand 1 (PD-L1) and major histocompatibility complex (MHC) I, microsatellite instability (MSI), mismatch repair (MMR) defect, tumor mutation burden (TMB), tertiary lymphoid structures (TLSs), and several transcriptional signatures, the sensitivity of these indicators remains to be further improved. Here, we integrated T-cell spatial distribution and intratumor transcriptional signals in predicting the response to immune checkpoint therapy in MMR-deficient tumors including tumors of Lynch syndrome (LS). In both cohorts, MMR-deficient tumors displayed personalized tumor immune signatures, including inflamed, immune excluded, and immune desert, which were not only individual-specific but also organ-specific. Furthermore, the immune desert tumor exhibited a more malignant phenotype characterized by low differentiation adenocarcinoma, larger tumor sizes, and higher metastasis rate. Moreover, the tumor immune signatures associated with distinct populations of infiltrating immune cells were comparable to TLSs and more sensitive than transcriptional signature gene expression profiles (GEPs) in immunotherapy prediction. Surprisingly, the tumor immune signatures might arise from the somatic mutations. Notably, patients with MMR deficiency had benefited from the typing of immune signatures and later immune checkpoint inhibition. Our findings suggest that compared to PD-L1 expression, MMR, TMB, and GEPs, characterization of the tumor immune signatures in MMR-deficient tumors improves the efficiency of predicting the responsiveness of immune checkpoint inhibition.

Responses to organic pollutants in the tropical Pacific and subtropical Atlantic Oceans by pelagic marine bacteria

Background and chronic pollution by organic pollutants (OPs) is a widespread threat in the oceans with still uncharacterized effects on marine ecosystems and the modulation of major biogeochemical cycles. The ecological impact and toxicity of this anthropogenic dissolved organic carbon (ADOC) is not related to the presence of a single compound but to the co-occurrence of a myriad of synthetic chemicals with largely unknown effects on heterotrophic microbial communities. We have analyzed the metabolic capacity of metagenome-assembled genomes (MAGs) of natural oceanic communities from the north Pacific (Costa Rica dome) and Atlantic oceans challenged with environmentally relevant levels of ADOC. In the Atlantic, ADOC-exposed MAGs responded transcriptionally more strongly compared to controls than in the Pacific, possibly mirroring the higher relevance of ADOC compounds as carbon source in oligotrophic environments. The largest proportions of transcripts originated from MAGs belonging in the families Rhodobacteraceae and Flavobacteriaceae, known to play a role on consumption of several OPs. In the Atlantic, archaeal Poseidoniales showed the highest transcription levels after 2 h of ADOC exposure, although no increase of relative abundances in the DNA pool was recorded after 24 h, whereas Methylophaga showed the opposite pattern. Both taxa are suggested to be actively involved in the consumption of biogenic alkanes produced by cyanobacteria. We observed similar gene expression profiles of alkane degradation and methylotrophy signature genes. These findings, plus the chemical degradation of alkanes measured in the experiments, provides experimental evidence of the consumption of anthropogenic hydrocarbons and synthetic chemicals at the low concentrations found in the ocean, and modulation of microbiomes by ADOC.

Primary Bone Lymphoma: A Review of the Literature with Emphasis on Histopathology and Histogenesis.

Primary bone lymphoma (PBL) is a rare neoplasm of malignant lymphoid cells presenting with one or more bone lesions without nodal or other extranodal involvement. It accounts for approximately 1% of all lymphomas and 7% of malignant primary bone tumors. Diffuse large B-cell lymphoma (DLBCL), not otherwise specified (NOS) represents the predominant histological type and constitutes over 80% of all cases. PBL may occur at all ages with a typical diagnosis age of 45-60 years and a slight male predominance. Local bone pain, soft tissue edema, palpable mass and pathological fracture are the most common clinical features. Diagnosis of the disease, which is frequently delayed due to its non-specific clinical presentation, is based on the combination of clinical examination and imaging studies and confirmed by combined histopathological and immunohistochemical examination. PBL can develop in any part of the skeleton, although it occurs most commonly in the femur, humerus, tibia, spine and pelvis. The imaging appearance of PBL is highly variable and unspecific. In terms of the cell-of-origin, most cases of primary bone DLBCL (PB-DLBCL), NOS belong to the germinal center B-cell-like subtype and specifically originate from germinal center centrocytes. PB-DLBCL, NOS has been considered a distinct clinical entity based on its particular prognosis, histogenesis, gene expression and mutational profile and miRNA signature. PBL carries a favorable prognosis, especially when treated with combined chemoradiotherapy.

Gene expression profiling and FDG-PET radiomics uncover radiometabolic signatures associated with outcome in DLBCL.

Emerging evidence indicates that chemoresistance is closely related to altered metabolism in cancer. Here, we hypothesized that distinct metabolic gene expression profiling (GEP) signatures might be correlated with outcome and with specific fluorodeoxyglucose positron emission tomography (FDG-PET) radiomic profiles in diffuse large B-cell lymphoma (DLBCL). We retrospectively analyzed a discovery cohort of 48 consecutive patients with DLBCL treated at our center with standard first-line chemoimmunotherapy by performing targeted GEP (T-GEP)- and FDG-PET radiomic analyses on the same target lesions at baseline. T-GEP-based metabolic profiling identified a 6-gene signature independently associated with outcomes in univariate and multivariate analyses. This signature included genes regulating mitochondrial oxidative metabolism (SCL25A1, PDK4, PDPR) that were upregulated and was inversely associated with genes involved in hypoxia and glycolysis (MAP2K1, HIF1A, GBE1) that were downregulated. These data were validated in 2 large publicly available cohorts. By integrating FDG-PET radiomics and T-GEP, we identified a radiometabolic signature (RadSig) including 4 radiomic features (histo kurtosis, histo energy, shape sphericity, and neighboring gray level dependence matrix contrast), significantly associated with the metabolic GEP-based signature (r= 0.43, P= .0027) and with progression-free survival (P= .028). These results were confirmed using different target lesions, an alternative segmentation method, and were validated in an independent cohort of 64 patients. RadSig retained independent prognostic value in relation to the International Prognostic Index score and metabolic tumor volume (MTV). Integration of RadSig and MTV further refined prognostic stratification. This study provides the proof of principle for the use of FDG-PET radiomics as a tool for noninvasive assessment of cancer metabolism and prognostic stratification in DLBCL.

Molecular analysis and favorable clinical outcomes in real-world patients with metastatic renal cell carcinoma

Background Prior biomarker studies have mainly been restricted to advanced RCC patients treated in clinical trials or have had limited integration of immunotherapy features such as programmed death ligand (PD-L)-1 with gene expression signatures intended to capture other canonical pathways to confirm their prognostic value. Material and methods PD-L1 and PD-L2 by immunohistochemistry (IHC), PD-L2 messenger RNA (mRNA), and 10 gene expression profile (GEP) signatures targeting immune, angiogenesis and canonical pathways were analyzed in nephrectomy specimens from 227 advanced clear cell RCC (ccRCC) and 42 non-clear cell RCC (nccRCC) patients treated with targeted therapies including VEGF and mTOR inhibitors. Biomarker association with best overall response (BOR), progression-free survival (PFS), and overall survival (OS) were evaluated using multivariable modeling. Except for PD-L1 IHC and angiogenesis, tested with a nominal p-value of .05, multiplicity control was applied with a 0.1 significance level given limited experience in this setting. Results The strongest biomarker correlations were observed for hypoxia inducible factor (HIF)-2a and angiogenesis signatures (rho = 0.860 [ccRCC], 0.819 [nccRCC]); hypoxia and glycolysis signatures (rho = 0.943 [ccRCC], 0.973 [nccRCC]); PD-L2 mRNA and T-cell-inflamed GEP signatures (rho = 0.764 [ccRCC], 0.897 [nccRCC]); and PD-L2 mRNA and monocytic myeloid-derived suppressor cell signature (rho = 0.787 [ccRCC], 0.815 [nccRCC]). For ccRCC, higher angiogenesis expression was associated with improved BOR (OR:2.85 [95%CI:1.37, 5.93]), longer PFS (HR:0.61 [95%CI:0.45, 0.82]) and OS (HR:0.74 [95%CI:0.54, 1.00]); higher PD-L1 expression with shorter OS (HR:1.44 [95%CI:1.01, 2.07]). For nccRCC, there was more than a two-fold increased risk with longer OS associated with lower angiogenesis (HR:2.43 [95%CI:1.04, 5.68]), glycolysis (HR:7.03 [95%CI:1.51, 32.76]) and hypoxia (HR:8.83 [95%CI:1.69, 46.05]) gene signature expression. Conclusion Data pointed at PD-L1 IHC and angiogenesis expression in ccRCC and hypoxia, glycolysis, and angiogenesis expression in nccRCC as potential prognostic factors. These findings may have implications for the design and interpretation of advanced RCC trials and to identify potential targets for combination therapy strategies.

Clinically relevant small-molecule promotes nerve repair and visual function recovery

Adult mammalian injured axons regenerate over short-distance in the peripheral nervous system (PNS) while the axons in the central nervous system (CNS) are unable to regrow after injury. Here, we demonstrated that Lycium barbarum polysaccharides (LBP), purified from Wolfberry, accelerated long-distance axon regeneration after severe peripheral nerve injury (PNI) and optic nerve crush (ONC). LBP not only promoted intrinsic growth capacity of injured neurons and function recovery after severe PNI, but also induced robust retinal ganglion cell (RGC) survival and axon regeneration after ONC. By using LBP gene expression profile signatures to query a Connectivity map database, we identified a Food and Drug Administration (FDA)-approved small-molecule glycopyrrolate, which promoted PNS axon regeneration, RGC survival and sustained CNS axon regeneration, increased neural firing in the superior colliculus, and enhanced visual target re-innervations by regenerating RGC axons leading to a partial restoration of visual function after ONC. Our study provides insights into repurposing of FDA-approved small molecule for nerve repair and function recovery.

Abstract LB523: Biomarker assessment of PTEN protein expression and gene expression profiling (GEP) in a phase III study of copanlisib in combination with rituximab in patients with indolent non-Hodgkin lymphoma (iNHL)

Abstract Introduction: The combination of the PI3K inhibitor copanlisib (C) plus the anti-CD20 antibody rituximab (R) has been shown to be superior to R plus placebo (P) in patients with relapsed iNHL (Matasar et al. Lancet Oncol 2021). We report here the biomarker analysis to assess correlation with response of baseline samples for PTEN expression and GEP signatures. Methods: Adult patients with relapsed B-cell iNHL were randomly assigned 2:1 to either C + R or P + R; standard dosing on a 28-day cycle applied. Either fresh or archival tumor tissues were collected for central pathology review and biomarker analysis. Extraction of the formalin-fixed, paraffin-embedded (FFPE) tissue slides was performed using the Qiagen AllPrep DNA/RNA FFPE Kit, where quality was assessed using a combination of Agilent TapeStation for integrity and ThermoFisher NanoDrop for quantity and purity. Immunohistochemistry (IHC) for PTEN expression was performed by Mosaic Laboratories (Lake Forest, CA, USA) and RNA sequencing analysis was performed by Almac Diagnostics (Durham, NC, USA). GEP was also conducted using claraT pathway signatures provided by Almac. Results: Patients with complete, very good partial, and partial objective responses were combined in a “responders” group and compared against all other patients (“non-responders” group). Data from PTEN IHC were available for 222 patients (149 for C + R; 73 for P + R). There was no statistically significant difference in response with PTEN presence or absence for the 3 subgroups - total iNHL, follicular lymphoma (FL), and non-FL. Also, baseline PTEN expression did not show significant correlation with best overall response. C + R treatment improved median progression-free survival (PFS) for all patients, with a statistically significant benefit to those with PTEN presence in all 3 subgroups. For patients treated with P + R, Kaplan-Meier plots and log-rank tests showed statistically improved median PFS in patients with PTEN absence vs PTEN presence in overall iNHL (p=0.031) and FL (p=0.0021). Data from GEP were available for 202 patients (133 for C + R; 69 for P + R). The association with best overall response and PFS was analyzed using specific biomarker gene sets and/or 23 preselected clinical parameters. Association of GEP analysis based on hypothesis-based modeling, single-gene hypothesis-free modeling, and claraT pathway signatures showed no predicted responsiveness or PFS that was statistically significant. Conclusions: C + R improved median PFS in the overall iNHL, FL, and non-FL groups, with a statistically significant improvement in the PTEN-positive population. In the P + R group, PTEN-positive patients had worse PFS in all 3 subgroups. Data from GEP and pathway analysis did not show correlation with overall response or PFS. Citation Format: Shalini Chaturvedi, Anke Schulz, Lidia Mongay Soler, Barrett H. Childs, Matthew Matasar, Pier Luigi Zinzani. Biomarker assessment of PTEN protein expression and gene expression profiling (GEP) in a phase III study of copanlisib in combination with rituximab in patients with indolent non-Hodgkin lymphoma (iNHL) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr LB523.

Lachnoclostridium and Immune Inflamed Gene Expression Signature Association in Head & Neck Cancers

<h3>Purpose/Objective(s)</h3> The immune microenvironment plays an essential role in the progression of head and neck squamous cell carcinoma (HNSCC). The association of the tumor microbiota and immune microenvironment is not well defined. The Cancer Genome Atlas Project (TCGA) analysis provided the diversity of microbiota in different cancer types. We analyzed the TCGA microbiome database to better understand the role of the tumor microbiome in HNSCC. <h3>Materials/Methods</h3> Human papillomavirus (HPV) positive and HPV negative HNSCC samples in the TCGA database were analyzed. Data were accessed using cBioPortal. Spearman's test was used to correlate Lachnoclostridium microbiome signature with immune-related gene expressions. <h3>Results</h3> Microbiome signatures were compared in PDL1 low and PDL1 high HNSCC. Lachnoclostridium was among the top genus enriched in the PDL1 high expression group in both HPV+ and HPV- HNSCC. Lachnoclostridium was correlated with immune inflamed gene expression profile. To evaluate the differential gene expressions in Lachnoclostridium enriched HNSCC, the gene expression profile of Lachnoclostridium high and low HNSCC samples were compared. MHC class I genes; HLA-A, HLA-B, HLA-C, HLA-E, HLA-F, TAP1, and TAP2 were among the top differentially expressed genes. Then we evaluated the correlation of MHC-I genes with Lachnoclostridium enrichment. Lachnoclostridium signature was significantly correlated with expression of these MHC I genes, with Spearman's correlation coefficient ranging between 0.51-0.59. <h3>Conclusion</h3> Lachnoclostridium is a recently defined genus found in the human gut microbiome. Here we, for the first time, identify the enrichment of this genus in high PDL1 expressing HNSCC. The association of Lachnoclostridium signature with the immune inflamed gene expression profile and MHC-I gene signature suggests its potential role in modulating the immune microenvironment in HNSCC.

GATA6 Expression as a predictor of response to perioperative chemotherapy in resectable pancreatic adenocarcinoma: A multicenter Canadian phase II study (NeoPancONE).

TPS638 Background: Prospective studies of the benefit of neoadjuvant chemotherapy in resectable pancreatic adenocarcinoma (PDAC) have been reported. The ideal peri-operative regimen is yet to be determined. Adjuvant FOLFIRINOX (mFFX) in resected PDAC has been proven to improve overall survival (OS) relative to adjuvant gemcitabine. An accepted perioperative approach involves delivering the majority of chemotherapy (6-8 cycles) in the pre-operative setting, while the remainder (of 12 cycles) is administered post-operatively. This pre-operative treatment period may allow for chemosensitivity assessment, and better patient selection for surgery, thereby improving R0 resection rates and reducing the frequency of early post-operative recurrence. Data from the COMPASS trial (NCT02750657) has shown that shown that low levels of the transcription factor GATA6 expression is a putative surrogate for the RNA Moffit signature and predictive of a chemoresistant phenotype in advanced PDAC. NeoPancONE will evaluate clinical outcomes and molecular biomarkers including GATA6 and radiomic biomarkers in pts with resectable PDAC treated with perioperative mFFX. Methods: NeoPancONE is a Phase 2, open-label, single arm study in pts with resectable PDAC. Tissue and serum are collected for biomarker testing, including GATA6 by FISH and IHC (1) with expression levels measured by RNAseq, and longitudinal ctDNA analysis. Pts with histologically confirmed, resectable PDAC and ECOG PS 0-1 will be recruited over 2.5 years. Resectability will be determined by central review as per NCCN guidelines. The primary objective is to evaluate disease-free survival in resectable PDAC treated with peri-operative mFFX according to baseline tumor GATA6 expression level. The ratio of GATA6-high to low is expected to be approximately 4:1[1]. Assuming 1-year disease-free survival of 65% in the GATA6-high, compared to 34% in the GATA6-low cohort, this corresponds to a hazard ratio of 2.5. With 80% power and a 5% 2-sided significance level, a total of 84 patients will be enrolled with 67 events expected in the GATA6 high cohort and 17 in GATA6 low. Participants will receive up to 6 cycles of neoadjuvant mFFX. After neoadjuvant chemotherapy, definitive surgical resection will proceed as deemed appropriate by a hepatobiliary surgeon. Post-operatively, pts will receive up to 6 cycles of adjuvant chemotherapy. Secondary objectives include determination of overall response rate, incidence of R0 resection, OS, Moffit gene expression profiling (RNAseq), ctDNA, and radiomic signatures to predict outcomes. Enrolment for NeoPancONE began in October 2020 and is being conducted at 8 sites across Canada. To date, 23 pts have been recruited. The study duration will be five years. Reference: O’Kane G M et al. Clin Can Res Sep 2020. Clinical trial information: NCT04472910.

An EZH2 Gene Expression Signature Is Predictive of Differential Efficacy of Chemotherapy Irrespective of EZH2 Mutation Status in Patients with Follicular Lymphoma Treated within the Gallium Trial

An EZH2 Gene Expression Signature Is Predictive of Differential Efficacy of Chemotherapy Irrespective of EZH2 Mutation Status in Patients with Follicular Lymphoma Treated within the Gallium Trial

Integration of Targeted Gene Expression Profiling and FDG-PET Radiomics Uncovers Radiometabolic Signatures Associated with Outcome in Diffuse Large B-Cell Lymphoma

Metabolic rewiring is a hallmark of cancer and a predominant feature of aggressive lymphoproliferative disorders such as diffuse large B-cell lymphomas (DLBCL), which need a reshaped metabolism in order to meet the increased demands related to rapid cell proliferation.Emerging evidence indicates that chemoresistance is closely related to altered metabolism in cancer. However, the relationship between metabolic rewiring and chemoresistance in lymphoma is yet to be elucidated. Radiomic analysis applied to functional imaging with fluoroedoxyglucose positron emission tomography (FDG-PET) provides a unique opportunity to explore DLBCL metabolism. In this study we hypothesized that distinct gene expression (GEP) signatures might be correlated with specific FDG-PET radiomics signatures, which in turn could be associated with resistance to standard chemoimmunotherapy and DLBCL outcome.First, we retrospectively analyzed a discovery cohort of 48 consecutive DLBCL patients (pts) treated at our center with standard first line R-CHOP/R-CHOP-like chemoimmunotherapy from 2010 to 2018, with available formalin-fixed paraffin embedded (FFPE) tissue from the initial diagnostic biopsy and FDG-PET radiomics data extracted from the same target lesion. Median follow-up was 55 months (range 18-110). We profiled this cohort with targeted-GEP (T-GEP) (NanoString platform), using a custom panel to define the cell of origin (COO) and MYC/BCL-2 levels, and a dedicated panel comprising 180 genes encompassing the most relevant cancer metabolism pathways. By applying the maxstat package we found that a 6-gene metabolic signature was strongly associated with outcome and outperformed the COO, the MYC/BCL-2 status and the International Prognostic Index (IPI) score for progression free survival (PFS) and overall survival (OS) in multivariate analysis. The 6-gene metabolic signature included genes regulating oxidative metabolism and fatty acid oxidation (SCL25A1, PDK4, PDPR) which were upregulated, and was inversely associated with genes involved in glycolytic pathways (MAP2K1, HIF1A, GBE1) which were downregulated. Notably 5-year PFS and OS were 100% and 95% in metabolic signature (met-Sig) low pts vs 24% and 45% in met-Sig high pts respectively (p<0.0001 for PFS and OS). There was no significant association between the COO, MYC/BCL-2 levels, standardized uptake value (SUV), and the 6-gene signature. The prognostic value of the 6-gene signature for OS was validated in 2 large publicly available cohorts of 469 (Sha et al. J Clin Oncol 2019) and 233 (Lenz et al. N Eng J Med 2005) pts. Next, we integrated PET radiomics and T-GEP data. Radiomics analysis (LifeX package) was performed by applying regions of interest semi-automatically, using a 25% SUV max threshold for segmentation. Fifty-five radiomic features (RFs) were extracted and 10 RFs significantly correlated either positively or negatively with the T-GEP metabolic signature (Spearman). After stability evaluation, applying a stepwise feature selection procedure, 4 RFs (Histo Curtosis, Histo Energy, Shape Sphericity, NGLDM Contrast) were used to generate a radiomic signature (hereafter called radiometabolic signature) characterized by the most significant correlation with both the metabolic T-GEP signature (r=0.43, p=0.0027) and PFS (p=0.004). These results (obtained analyzing the lesion of the initial diagnostic biopsy), were confirmed using different target lesions (i.e. the most FDG-avid and the largest lesion), and were validated in a second independent cohort of 64 patients (validation cohort) treated at our center in the same period of time (with no FFPE tissue available). A multivariate analysis performed in the whole cohort of 112 pts (discovery + validation) indicated that the radiometabolic signature retained independent prognostic value in relation to the IPI score and metabolic tumor volume. The robustness of the radiometabolic signature was further confirmed by using a second segmentation method (fixed 2.5 SUV max threshold).These data indicate that oxidative metabolic rewiring could be a powerful adverse prognostic predictor, suggesting the possibility of targeting oxidative metabolism to overcome chemorefractoriness in DLBCL. This study provides the proof of principle for the use of FDG-PET radiomics as a tool for non-invasive assessment of cancer metabolism, and for predicting metabolic vulnerabilities in DLBCL. [Display omitted] DisclosuresTarella: ADC-THERAPEUTICS: Other: ADVISORY BOARD; Abbvie: Other: ADVISORY BOARD. Pileri: CELGENE: Other: ADVISORY BOARD; ROCHE: Other: ADVISORY-BOARD; NANOSTRING: Other: ADVISORY BOARD. Derenzini: TAKEDA: Research Funding; BEIGENE: Other: ADVISORY BOARD; ASTRA-ZENECA: Consultancy, Other: ADVISORY-BOARD; TG-THERAPEUTICS: Research Funding; ADC-THERAPEUTICS: Research Funding.

688P Gene expression profiling (GEP) signatures associated with markers of sensitivity to immune and angiogenic therapy in clear-cell renal cell carcinoma (ccRCC) with sarcomatoid/rhabdoid features

Gene expression profiling studies have identified angiogenic and immune sig. with potential predictive value in patients (pts) with advanced ccRCC. We aimed to update the findings of a large multi-institutional genomics database (Barata, ASCO-GU 21), with a focus on tumors with sarcomatoid and rhabdoid features.