1,255 research outputs found

    The local immunological microenvironment in colorectal cancer as a prognostic factor for treatment decisions in the clinic: The way ahead

    No full text
    Analysis of the local immunological microenvironment in colorectal cancer lesions yielded prognostic markers. Harnessing these insights for clinical application however requires the use of sophisticated technology and algorithms, especially the robust and reproducible quantification of immune cells. These technologies are available and will allow individualized treatment decisions beyond the current standard

    Abstract 1917: Immunological Tumor Maps: a Landscape of Infiltrating Immune Cells in Colorectal Cancer Based on Complete Tissue Section Analyses

    No full text
    Abstract In colorectal cancer (CRC) large scale tissue microarray (TMA) based quantitative immune cell counts using immune cell surface molecules (CD3, CD8, Granzyme B, and CD45RO) have identified the number of infiltrating immune cells to be potentially better predictors for patient survival than the classical TNM system. The spatial heterogeneity of immune cells may not be well reflected in the highly selected, and typically small (0,6-1 mm2) tissue cores of the TMA. This represents an obstacle in the individual prognosis prediction or classification of a single patient. To investigate this aspect, the localization and distribution of immune cell subpopulations based on the analysis of complete tissue sections by a dedicated novel staining and imaging system were performed. Using a specialized staining platform and whole slide imaging &amp; analysis by virtual microscopy (VM), immunological “tumor maps” were generated. These tumor maps are based on cell densities in fields of 1mm2 size, visualizing intratumoral heterogeneity for the surface markers CD3, CD8, Granzyme B, and CD45RO. In total, an area of 867 mm2 was automatically evaluated with an average of 48 mm2 of evaluated tumor tissue per patient slide. Cell counts varied within a patient significantly, ranging from 0 to up to 2550 cells / mm2. Further analyses revealed, that sampling of single field counts within the tumor can only yield clear diagnostic decisions for a fraction of the analyzed patients, with ambiguous decisions for 11 out of 20 patients. Interestingly, the overall degree of heterogeneity also varied between patients, with lower heterogeneity found only in samples with lower cell counts. No samples with a homogeneous high cell density distribution were observed. The observed variability has implications for the individual prognosis prediction and represents the first spatial quantitative study of immune cells in a set of CRC primary tumors. The presented tumor maps therefore are a suitable tool to visualize heterogeneity. Furthermore, whole slide imaging &amp; analysis by VM is essential in the identification of prognostic markers as well as in their subsequent application. In the future, spatial marker signatures could contribute to individual patient classification. Note: This abstract was not presented at the AACR 101st Annual Meeting 2010 because the presenter was unable to attend. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1917.</jats:p

    Automatic tumor-stroma separation in fluorescence TMAs enables the quantitative high-throughput analysis of multiple cancer biomarkers.

    No full text
    The upcoming quantification and automation in biomarker based histological tumor evaluation will require computational methods capable of automatically identifying tumor areas and differentiating them from the stroma. As no single generally applicable tumor biomarker is available, pathology routinely uses morphological criteria as a spatial reference system. We here present and evaluate a method capable of performing the classification in immunofluorescence histological slides solely using a DAPI background stain. Due to the restriction to a single color channel this is inherently challenging. We formed cell graphs based on the topological distribution of the tissue cell nuclei and extracted the corresponding graph features. By using topological, morphological and intensity based features we could systematically quantify and compare the discrimination capability individual features contribute to the overall algorithm. We here show that when classifying fluorescence tissue slides in the DAPI channel, morphological and intensity based features clearly outpace topological ones which have been used exclusively in related previous approaches. We assembled the 15 best features to train a support vector machine based on Keratin stained tumor areas. On a test set of TMAs with 210 cores of triple negative breast cancers our classifier was able to distinguish between tumor and stroma tissue with a total overall accuracy of 88%. Our method yields first results on the discrimination capability of features groups which is essential for an automated tumor diagnostics. Also, it provides an objective spatial reference system for the multiplex analysis of biomarkers in fluorescence immunohistochemistry

    Spatial intratumoral heterogeneity of proliferation in immunohistochemical images of solid tumors

    No full text
    The interactions of neoplastic cells with each other and the microenvironment are complex. To understand intratumoral heterogeneity, subtle differences should be quantified. Main factors contributing to heterogeneity include the gradient ischemic level within neoplasms, action of microenvironment, mechanisms of intercellular transfer of genetic information, and differential mechanisms of modifications of genetic material/proteins. This may reflect on the expression of biomarkers in the context of prognosis/stratification. Hence, a rigorous approach for assessing the spatial intratumoral heterogeneity of histological biomarker expression with accuracy and reproducibility is required, since patterns in immunohistochemical images can be challenging to identify and describe

    Sequence mutations of the substrate binding pocket of stem cell factor and multidrug resistance protein ABCG2 in renal cell cancer: a possible link to treatment resistance

    No full text
    ABCG2 is a multidrug cellular transport protein that is associated with resistance to certain treatments in patients, particularly anticancer treatment. The tumor-protective properties of ABCG2 expression are reported to be a feature of a subset of stem cell-like tumor cells. While protection against chemotherapy has been well analyzed, the role of ABCG2 in the treatment with tyrosine kinase inhibitors is only partially understood. Tyrosine kinase inhibitors are currently the main treatment option in irresectable renal cell carcinomas. To investigate possible underlying sequence variations in the ABCG2 gene with relevance to the functional properties of the protein, 36 patient samples were analyzed. Using sequence analysis and single-nucleotide polymorphism databases, sequence variations in the highly conserved domains of the binding pocket of ABCG2 were analyzed. The resulting variations were used for computational protein prediction algorithms to identify conformational alterations. A relevant shift from A to G at position 1376 (resulting in Y→C at 459 aa) was identified and found to be present in 8.3% of the patients. These patients are currently in follow-up after resection, thus, further analysis will reveal whether this mutation has relevance to treatment efficacy

    Quantification of prognostic immune cell markers in colorectal cancer using whole slide imaging tumor maps

    No full text
    To analyze intratumoral heterogeneity of immune cells and the resulting impact of heterogeneity on the level of individual patient prediction

    Quantification of prognostic immune cell markers in colorectal cancer using whole slide imaging tumor maps

    No full text
    To analyze intratumoral heterogeneity of immune cells and the resulting impact of heterogeneity on the level of individual patient prediction
    corecore