Circulating tumor cell copy-number heterogeneity in ALK-rearranged non-small-cell lung cancer resistant to ALK inhibitors

Gatekeeper mutations are identified in only 50% of the cases at resistance to Anaplastic Lymphoma Kinase (ALK)-tyrosine kinase inhibitors (TKIs). Circulating tumor cells (CTCs) are relevant tools to identify additional resistance mechanisms and can be sequenced at the single-cell level. Here, we provide in-depth investigation of copy number alteration (CNA) heterogeneity in phenotypically characterized CTCs at resistance to ALK-TKIs in ALK-positive non-small cell lung cancer. Single CTC isolation and phenotyping were performed by DEPArray or fluorescence-activated cell sorting following enrichment and immunofluorescence staining (ALK/cytokeratins/CD45/Hoechst). CNA heterogeneity was evaluated in six ALK-rearranged patients harboring ≥ 10 CTCs/20 mL blood at resistance to 1st and 3rd ALK-TKIs and one presented gatekeeper mutations. Out of 82 CTCs isolated by FACS, 30 (37%) were ALK+/cytokeratins-, 46 (56%) ALK-/cytokeratins+ and 4 (5%) ALK+/cytokeratins+. Sequencing of 43 CTCs showed hi..... READ ARTICLE

Precision Oncology DOI:10.1038/s41698-021-00203-1

Authors: Marianne Oulhen, Patrycja Pawlikowska, Tala Tayoun, Marianna Garonzi, Genny Buson, Claudio Forcato, Nicolò Manaresi, Agathe Aberlenc, Laura Mezquita, Yann Lecluse, Pernelle Lavaud, Charles Naltet, David Planchard, Benjamin Besse & Françoise Farace

Pre-Clinical, group4Kirk SmithJuly 16, 2021ALK, heterogeneity, single circulating tumor cells, RTK/RAS, EMT

Heterogeneous Tumor-Immune Microenvironments between Primary and Metastatic Tumors in a Patient with ALK Rearrangement-Positive Large Cell Neuroendocrine Carcinoma

We present a case study of a 32-year-old female patient with ALK-rearrangement-positive LCNEC, who had multiple distant metastases including mediastinal lymph-node, bilateral breasts, multiple bones, liver and brain. Multiple biopsy samples obtained from primary lung and three metastatic tumors were analyzed by fluorescent multiplex immunohistochemistry. Tissue localizations of tumor-infiltrating lymphocytes in the tumor nest and surrounding stroma were evaluated. T cell and B cell infiltrations were decreased with distance from primary lung lesion. Although each tumor displayed a unique TIME, all tumors exhibited concomitant regression after treatment with an ALK-inhibitor. This study provides the first evidence of the coexistence of distinct TIME within a single individual with ALK-rearrangement-positive LCNEC. The present study contributes to our understanding of heterogeneous TIMEs between primary and metastatic lesions and provides new insights into the complex interplay between host-immunity and cancer cells in primary and metastatic lesions. READ ARTICLE

International Journal of Molecular Science DOI: 10.3390/ijms21249705

Authors: Tashiro T, Imamura K, Tomita Y, Tamanoi D, Takaki A, Sugahara K, Sato R, Saruwatari K, Sakata S, Inaba M, Ushijima S, Hirata N, Sakagami T

Case StudyKirk SmithDecember 19, 2020B cell, ALK, heterogeneity, immune checkpoint, large cell neuroendocrine carcinoma, LCNEC, neuroendocrine tumors, NET, PD-L1, regulatory T-cells, Tregs, tumor-immune microenvironments, TIME, tumor-infiltrating lymphocyte, TIL