Patient-derived cancer cells to dissect the molecular basis of treatment response in primary liver cancer: a mechanistic and functional approach
Date issued
Authors
Editors
Journal Title
Journal ISSN
Volume Title
Publisher
License
Abstract
Hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA) are two major types of primary liver cancers (PLC), ranking among the deadliest cancers worldwide with poor overall survival rates. Lack of clinical symptoms and effective biomarkers for early detection are main causes of late diagnosis. Despite identification of several potentially drugable targets and subsequent development of next-generation targeted therapies, translation of these findings into clinical practice remains challenging. Further, there is a lack of models that truly and accurately represent morphological and molecular heterogeneity of original tumors. Therefore, development of primary culture models that closely recapitulate phenotypic and molecular diversities of PLC is urgently needed to support a translation from laboratory studies to the bedside and improve patient outcome.
In the here presented thesis, we report successful establishment and detailed characterization of seven patient-derived liver cancer cell lines (PDCL) from HCC and intrahepatic CCA. Morphological and histological characteristics of obtained cell lines and xenograft tumors were analyzed and compared to original tumors. Tumor grading and genomic stability were further assessed to determine background setting for successful PDCL establishment. Time course analyses of transcriptomic and genomic changes were performed using next-generation sequencing (NGS) to characterize and generate molecular profiles of newly derived PDCL and investigate how accurately they recapitulate original cancer tissue. Key oncogenic alterations were identified by targeted NGS and cell lines carrying potentially actionable mutations were treated with corresponding specific inhibitors. Long-term cultivation effect on treatment response to classic chemotherapeutics was monitored.
Our results show that PDCL fully resembled morphological features of the primary cancers in vitro and in vivo over extended period in culture. We also provide evidence that less differentiated tumors with higher genomic instability possess a higher likelihood of successful PDCL establishment. Genomic analyses confirmed that PDCL retain similar profile as corresponding primary tumors during long-term culturing. Targeted-NGS demonstrated that key oncogenic alterations such as TP53, KRAS, CTNNB1 as well as actionable mutations (e.g. MET, KIT, KDR) were highly conserved in PDCL and amenable for individualized therapeutic approaches. Integrative genomic and transcriptomic approaches further demonstrated that PDCL more closely resemble molecular and prognostic features of PLC than established cell lines.
Our integrative analysis demonstrates that PDCL represents refined model for discovery of relevant molecular subgroups and exploration of precision medicine approaches for the treatment of primary liver cancer.