Virtual Library
Start Your Search
M.W. Backman
Author of
-
+
MA 06 - Lung Cancer Biology I (ID 660)
- Event: WCLC 2017
- Type: Mini Oral
- Track: Biology/Pathology
- Presentations: 1
- Moderators:N. Motoi, Keith M Kerr
- Coordinates: 10/16/2017, 15:45 - 17:30, Room 501
-
+
MA 06.01 - Cancer Testis Antigens and Mutational Load in Relation to the Immune Landscape of Non-Small Cell Lung Cancer (ID 9369)
15:45 - 15:50 | Author(s): M.W. Backman
- Abstract
- Presentation
Background:
The avoidance of immune surveillance by tumor cells is an accepted hallmark of cancer. The aim of this study was to describe the natural immune landscape of NSCLC tissue, to identify important regulatory associations and potential targets of immune response. This includes mutational load and cancer testis antigen (CTA) expression, and the comprehensive analysis of tumor infiltrating immune cells in connection with immune signaling and clinical information.
Method:
Tissue microarrays including duplicate cancer samples of 357 NSCLC patients were stained with antibodies against CD3, CD4, CD8, CD45RO, FoxP3, CD20, CD138, and CD44 to analyze the protein expression in the stroma and tumor compartment. For 197 of these cases, corresponding RNA-seq data were available. The immunological data were correlated to the transcriptomic data and to patients’ clinical outcome. The mutation status and the mutational load was based on a targeted next-generation sequencing panel of 82 genes (HaloPlex).
Result:
The immune cell infiltration was predominantly in the stroma, although CD8 and FoxP3 cells also showed relevant infiltration of the tumor cell compartment. The amount of T-cells of different subsets and CD20-positive B-cells correlated positively to each other. A higher mutational load was associated with higher CD8 T-cell infiltrates, CD45RO cells, FoxP3 regulatory cells as well as CD20-positive B-cells in the tumor compartment. In contrast, the number of expressed CTAs were associated with an abundance of CD45RO-positive cells in the stromal compartment. Only CD44-positivity (HR = 0.61, p< 0.01) as well as high CD20 positive B-cells (HR = 0.34, p< 0.01) and plasma cell (CD138, HR = 0.71, p< 0.05) counts in the tumor, and for plasma cells also the stromal (HR = 0.61, p< 0.01), compartment were associated with longer overall survival.
Conclusion:
Here we describe natural immune profiles in a large clinical NSCLC patient cohort. Interestingly both mutational load and CTA expression is associated with the abundance of distinct immune cell infiltrates. We could not confirm the impact of tumor infiltrating T-cells on survival. However, the consistent prognostic impact of both B-cell markers indicates a major role of the humoral immune response in lung cancer.
Only Members that have purchased this event or have registered via an access code will be able to view this content. To view this presentation, please login, select "Add to Cart" and proceed to checkout. If you would like to become a member of IASLC, please click here.
-
+
P1.07 - Immunology and Immunotherapy (ID 693)
- Event: WCLC 2017
- Type: Poster Session with Presenters Present
- Track: Immunology and Immunotherapy
- Presentations: 1
- Moderators:
- Coordinates: 10/16/2017, 09:30 - 16:00, Exhibit Hall (Hall B + C)
-
+
P1.07-021 - Multiplex Immune Profiling Identifies Prognostic Importance of the Spatial Co-Localization of Immune Cells in NSCLC (ID 9419)
09:30 - 09:30 | Author(s): M.W. Backman
- Abstract
Background:
There is an increasing impact of the immunotherapy in the treatment of NSCLC. The accurate characterization of immune cell infiltrates in the in situ environment of cancer is regarded to be of major importance to predict prognosis and to guide therapy. The aim of this study was to perform a multi-marker characterization of immune cells and to evaluate their spatial distribution patterns with regard to patient survival.
Method:
A tissue microarray including 55 cases of non-small cell lung cancer (NSCLC) was used to perform multiplex immuno-fluorescent staining with antibodies against CD8, CD20, CD4, FoxP3, CD45RO and pan-cytokeratin (Opal, Perkin Elmer). The staining was digitalized by a multispectral imaging system (Vectra 3, PerkinElmer). Single cell marker expression profiles and their tissue coordinates were used to evaluate cell quantity and spatial distribution patterns. The data were validated with conventional immunohistochemical staining on consecutive sections.
Result:
Based on the co-expression of single immune markers we determined eight different classes of immune cells. While CD8+ single positive cells are evenly distributed in the stroma and tumor cell compartment, CD20+ and CD4+ cells were predominantly located in the stroma. Based on the immune cell subtypes we could define patients with a predominant B-cell response and patient with dominating T-cell infiltrates. No statistically significant impact on survival was found with regard to the abundance of immune cell subpopulations. When the spatial relation of stromal CD8+ regulatory T cells (CD8+FoxP3+) was considered, the shorter distance (< 20 μm) between CD8+FoxP3+ cells and tumor cells was associated with shorter survival (median 34 vs. 76 month, HR=2.6, 95%CI 1.3-6.8, log-rank p<0.01).
Conclusion:
The fluorescence multiplexed IHC technique provides a multi-marker characterization and spatial information for single cell-level analysis of immune infiltration patterns. Spatial localization of CD8+ regulatory T lymphocytes in relation to cancer cells is associated with overall survival in NSCLC.
-
+
P2.02 - Biology/Pathology (ID 616)
- Event: WCLC 2017
- Type: Poster Session with Presenters Present
- Track: Biology/Pathology
- Presentations: 2
- Moderators:
- Coordinates: 10/17/2017, 09:30 - 16:00, Exhibit Hall (Hall B + C)
-
+
P2.02-023 - Targeted Gene Expression Profiling to Evaluate Minimal Diagnostic FFPE-Biopsies from NSCLC-Patients (ID 9786)
09:30 - 09:30 | Author(s): M.W. Backman
- Abstract
Background:
The molecular analysis of non-small cell lung cancer (NSCLC) is limited by the availability of only small biopsies or cytological specimens that are procured for diagnostic purpose. The nuclease protection method provides the possibility to analyze minimal amount of formalin fixed paraffin embedded (FFPE) tissue without previous extraction steps. We tested this technique and compared it to the traditional methods RNA sequencing (RNAseq) and immunohistochemistry (IHC).
Method:
The nuclease protection method (HTGmolecular) in combination with next-generation sequencing was used to measure gene expression of 549 immune-oncology genes in FFPE samples from NSCLC-patients. Standardized minimal tissue amounts were used for 12 samples (4 tissue circles, 4µm thick, 1 mm in diameter, from a tissue microarray). Of these tissue sections also two corresponding original tumor biopsy were analyzed. RNA sequencing data was available from a corresponding fresh frozen tissue as well as IHC annotation of the immune markers FOXP3, CDH1, CD20, CD44, CD3, CD4, CD8 and PD-L1 on the analyzed tissue cores.
Result:
Of the 12 core preparations, 9 samples were successfully analyzed and fulfilled the quality criteria in the first run, the three others in a second re-analysis. The mRNA expression profiles of 12 samples measured with HTG on minute FFPE samples and RNAseq from fresh frozen tissue showed most often good correlations (r=0.41-0.87). HTG based mRNA data correlated with IHC expression for 5 of 8 genes (PD-L1 r=0.76, CD44 r=0.75, CDH1 r=0.61, CD8 r=0.60, CD4 r=0.54). RNAseq data showed good correlations with IHC for only 3 of 8 genes (CD44 r=0.91, PD-L1 r=0.86, CD8 r=0.67). Also, the HTG data of the two biopsies demonstrated very good correlations to the corresponding tissue cores and the RNAseq data (r>0.91). Finally, technical replicates of 10 of the minimal tissue core samples measured in different laboratories revealed relatively good concordance (r=0.71-0.94).
Conclusion:
The applied nuclease protection technique opens the possibility to multiplex and analyze the immune profile of 549 genes in minimal diagnostic biopsies with a high success rate. This is of great value for clinical use or in NSCLC clinical studies where the amount of tissue often is a limiting factor in companion diagnostics.
-
+
P2.02-066 - Identification of Crucial Gene Targets in the in Situ Environment of Cancer by Google Network Ranking (ID 10151)
09:30 - 09:30 | Author(s): M.W. Backman
- Abstract
Background:
The vast majority of cancer driver genes in non-small cell lung cancer (NSCLC) are characterized by activating mutations or high gene copy number amplifications. To identify tumorigenic genes without any genomic aberrations remains difficult. Network analysis of gene expression provides the possibility to describe the relations of genes to each other and by that to estimate their importance.
Method:
To analyze gene networks of NSCLC we applied the PageRank algorithm that was established by Google primarily to order the importance of websites. Data from NSCLC cancer tissue (n=1002) and normal lung (n=110) were retrieved from the cancer genome atlas (TCGA) and the highest expressed genes (n=16000) were ranked according to their importance in normal lung tissue as well as in NSCLC tissue. Subsequently, the difference in rank between normal and cancer was analyzed. Four comparative categories were defined and were analyzed with respect to their cellular function (GO annotation) and survival. Additionally, organ specific (n=163), housekeeping (n=68) and lung cancer related genes (n=62) were compared in the networks.
Result:
Genes with the highest importance (top 100) in normal lung tissue were connected with cellular metabolic processes or membrane transport. In cancer, most genes (top 100) were related to cell cycle and mitosis, chromosomal localization and DNA processing. There was no overlap between the two lists. Organ specific genes increased in average in their rank (p<0.001) while housekeeping genes decreased (p<0.001). Notably, cancer related genes did not significantly change their relevance in the network. Among the genes (top 100) that increased rank from normal to cancer, many were related to antigen processing and presentation.
Conclusion:
The PageRank algorithm provides the possibility to unbiasedly evaluate the importance of genes in the gene expression network of cancer. Surprisingly, not traditional cancer related genes but several hitherto not recognized genes were identified to be of regulatory importance and may be target for therapy. Once again, our results indicate the significance of the immune response in changes related to cancer.
