Other - Skin cancer
The heterogeneity of tumor cells presents a major challenge to cancer diagnosis and therapy. Cutaneous T cell lymphomas (CTCL) are a group of T lymphocyte malignanciesthat primarily affect skin. Lack of highly specific markers for malignant lymphocytes prevents early diagnosis, while only limited treatment options are available for patients with advanced-stage CTCL.Using single-cell RNA-sequencing analysis we profiled the transcriptomes of malignant and reactive T lymphocytes in advanced-stage CTCL skin tumors to identify specific markers for diagnosis and cure of CTCL.Single-cell transcriptional profiles displayed intra- and inter-tumor lymphocyte heterogeneity but also a common gene expression signature among several advanced-stage CTCL skin tumors, likely identifying highly proliferating malignant lymphocytes. Analysis of tumor infiltrating T lymphocytes revealed heterogeneity in effector and exhaustion programs across patient samples. Thus, our single-cell analyses of CTCL skin tumor samples provide new insight into disease pathogenesis and progression by showing patient-specific landscapes of malignant and reactive lymphocytes within the local microenvironment of each tumor, thus opening avenues for tailoring therapy to specific patients.