Project description:We evaluated linked-read whole genome sequencing (WGS) for detection of structural chromosomal rearrangements in primary samples of varying DNA quality from 12 patients diagnosed with ALL. Linked-read WGS enabled precise, allele-specific, digital karyotyping at a base-pair resolution for a wide range of structural variants including complex rearrangements, aneuploidy assessment and gene deletions. Additional RNA-sequencing and copy number aberrations (CNA) data from Illumina Infinium arrays were also generated and assessed against the linked-read WGS data. RNA-sequencing data was used to support structural chromosomal rearrangements detected in the linked-read WGS data by detecting expressed fusion genes as a consequence of the rearrangements. Illumina Infinium arrays (450k array and/or SNP array) were used to assess CNA status to further support the findings in the linked-read WGS data. The processed CNA data from the primary ALL patient samples has been deposited to GEO. RNA-sequencing, linked-read WGS data, and raw SNP array data from the primary ALL patient samples will not be deposited because the patient/parent consent does not cover depositing data that may be used for large-scale determination of germline variants in a repository. The ALL samples were collected 10-20 years ago from pediatric patients aged 2-15 years, some whom have deceased. The linked-read WGS data and the RNA-sequencing data sets generated in the study are available upon reasonable request from the corresponding author Jessica.Nordlund@medsci.uu.se.
Project description:We evaluated linked-read whole genome sequencing (WGS) for detection of structural chromosomal rearrangements in primary samples of varying DNA quality from 12 patients diagnosed with ALL. Linked-read WGS enabled precise, allele-specific, digital karyotyping at a base-pair resolution for a wide range of structural variants including complex rearrangements, aneuploidy assessment and gene deletions. Additional RNA-sequencing and copy number aberrations (CNA) data from Illumina Infinium arrays were also generated and assessed against the linked-read WGS data. RNA-sequencing data was used to support structural chromosomal rearrangements detected in the linked-read WGS data by detecting expressed fusion genes as a consequence of the rearrangements. Illumina Infinium arrays (450k array and/or SNP array) were used to assess CNA status to further support the findings in the linked-read WGS data. The processed CNA data from the primary ALL patient samples has been deposited to GEO. RNA-sequencing, linked-read WGS data, and raw SNP array data from the primary ALL patient samples will not be deposited because the patient/parent consent does not cover depositing data that may be used for large-scale determination of germline variants in a repository. The ALL samples were collected 10-20 years ago from pediatric patients aged 2-15 years, some whom have deceased. The linked-read WGS data and the RNA-sequencing data sets generated in the study are available upon reasonable request from the corresponding author Jessica.Nordlund@medsci.uu.se.
Project description:We evaluated linked-read whole genome sequencing (WGS) for detection of structural chromosomal rearrangements in primary samples of varying DNA quality from 12 patients diagnosed with ALL. Linked-read WGS enabled precise, allele-specific, digital karyotyping at a base-pair resolution for a wide range of structural variants including complex rearrangements, aneuploidy assessment and gene deletions. Additional RNA-sequencing and copy number aberrations (CNA) data from Illumina Infinium arrays were also generated and assessed against the linked-read WGS data. RNA-sequencing data was used to support structural chromosomal rearrangements detected in the linked-read WGS data by detecting expressed fusion genes as a consequence of the rearrangements. Illumina Infinium arrays (450k array and/or SNP array) were used to assess CNA status to further support the findings in the linked-read WGS data. The processed CNA data from the primary ALL patient samples has been deposited to GEO. RNA-sequencing, linked-read WGS data, and raw SNP array data from the primary ALL patient samples will not be deposited because the patient/parent consent does not cover depositing data that may be used for large-scale determination of germline variants in a repository. The ALL samples were collected 10-20 years ago from pediatric patients aged 2-15 years, some whom have deceased. The linked-read WGS data and the RNA-sequencing data sets generated in the study are available upon reasonable request from the corresponding author Jessica.Nordlund@medsci.uu.se.
Project description:Pancreatic ductal adenocarcinoma (PDAC) occurs as a complex, multifaceted event driven by the interplay of tumor permissive genetic mutations, nature of cellular origin and microenvironmental stress. In this study, we present a novel model to screen previously underappreciated tumor suppressor genes in human pancreatic acinar-derived PDAC and probe their implications under nutrient deprived environmental context. Primary human pancreatic acinar 3D organoids were engineered to harbor triple PDAC driver mutations—KRAS G12V, TP53 inactivation, and CDKN2A deletion (designated as KPT organoids). Using a pooled CRISPR knockout library targeting 199 potential tumor suppressors curated from recurrent mutations in clinical PDAC samples, we performed in vivo and in vitro screening with KPT cells and revealed significant enrichment of a list of candidate tumor suppressors, with NF2 emerging as the top target. Functional validation confirmed that loss of NF2 promotes the transition of PDAC from a non-invasive to an invasive state, potentially through extracellular matrix (ECM) modulation. Additionally, we found that the fibroblast heterogeneity in these organoids-derived tumors correlates with the cancer progression, suggesting the important roles of cancer-stroma communications in tumor evolution. Strikingly, NF2 inactivation was found to enhance PDAC cell fitness under nutrient starvation, a condition reflective of the harsh tumor microenvironment. This adaptation not only reinforces the oncogenic state but also confers therapeutical resistance. These findings establish NF2 as a critical tumor suppressor in PDAC and uncover its role in mediating nutrient adaptation and drug resistance. Importantly, this study provides new insights into drug resistance mechanisms and potential therapeutic targets in PDAC.
Project description:Pancreatic ductal adenocarcinoma (PDAC) occurs as a complex, multifaceted event driven by the interplay of tumor permissive genetic mutations, nature of cellular origin and microenvironmental stress. In this study, we present a novel model to screen previously underappreciated tumor suppressor genes in human pancreatic acinar-derived PDAC and probe their implications under nutrient deprived environmental context. Primary human pancreatic acinar 3D organoids were engineered to harbor triple PDAC driver mutations—KRAS G12V, TP53 inactivation, and CDKN2A deletion (designated as KPT organoids). Using a pooled CRISPR knockout library targeting 199 potential tumor suppressors curated from recurrent mutations in clinical PDAC samples, we performed in vivo and in vitro screening with KPT cells and revealed significant enrichment of a list of candidate tumor suppressors, with NF2 emerging as the top target. Functional validation confirmed that loss of NF2 promotes the transition of PDAC from a non-invasive to an invasive state, potentially through extracellular matrix (ECM) modulation. Additionally, we found that the fibroblast heterogeneity in these organoids-derived tumors correlates with the cancer progression, suggesting the important roles of cancer-stroma communications in tumor evolution. Strikingly, NF2 inactivation was found to enhance PDAC cell fitness under nutrient starvation, a condition reflective of the harsh tumor microenvironment. This adaptation not only reinforces the oncogenic state but also confers therapeutical resistance. These findings establish NF2 as a critical tumor suppressor in PDAC and uncover its role in mediating nutrient adaptation and drug resistance. Importantly, this study provides new insights into drug resistance mechanisms and potential therapeutic targets in PDAC.
Project description:Pancreatic ductal adenocarcinoma (PDAC) occurs as a complex, multifaceted event driven by the interplay of tumor permissive genetic mutations, nature of cellular origin and microenvironmental stress. In this study, we present a novel model to screen previously underappreciated tumor suppressor genes in human pancreatic acinar-derived PDAC and probe their implications under nutrient deprived environmental context. Primary human pancreatic acinar 3D organoids were engineered to harbor triple PDAC driver mutations—KRAS G12V, TP53 inactivation, and CDKN2A deletion (designated as KPT organoids). Using a pooled CRISPR knockout library targeting 199 potential tumor suppressors curated from recurrent mutations in clinical PDAC samples, we performed in vivo and in vitro screening with KPT cells and revealed significant enrichment of a list of candidate tumor suppressors, with NF2 emerging as the top target. Functional validation confirmed that loss of NF2 promotes the transition of PDAC from a non-invasive to an invasive state, potentially through extracellular matrix (ECM) modulation. Additionally, we found that the fibroblast heterogeneity in these organoids-derived tumors correlates with the cancer progression, suggesting the important roles of cancer-stroma communications in tumor evolution. Strikingly, NF2 inactivation was found to enhance PDAC cell fitness under nutrient starvation, a condition reflective of the harsh tumor microenvironment. This adaptation not only reinforces the oncogenic state but also confers therapeutical resistance. These findings establish NF2 as a critical tumor suppressor in PDAC and uncover its role in mediating nutrient adaptation and drug resistance. Importantly, this study provides new insights into drug resistance mechanisms and potential therapeutic targets in PDAC.
Project description:With a five-year survival rate of 9%, pancreatic ductal adenocarcinoma (PDAC) the deadliest of all cancers. The rapid mortality makes PDAC difficult to research, and inspires a resolve to create reliable, tractable cellular models for preclinical cancer research. PDAC organoids are increasing used to model PDAC as they maintain the differentiation status, molecular and genomic signatures of the original tumour. In this paper, we present novel methodologies and experimental approaches to develop PDAC organoids from PDX tumours, and the simultaneous development of matched primary cell lines. Moreover, we also identify a method of recapitulating primary cell line cultures to organoids (CLOs). We highlight the usefulness of CLOs as PDAC organoid models, as they maintain similar transcriptomic signatures as their matched patient-derived organoids and PDXs. These models provide a manageable, expandable in vitro resource for downstream applications such as high throughput screening, functional genomics, and tumour microenvironment studies.
Project description:This project investigated whether patient-derived organoids (PDOs) can enhance the accurate identification of somatic mutation and tumor-specific neoantigens in PDAC, which generally present with low tumor cellularity. Surgically resected PDAC tumors and their paired PDOs from 21 patients were examined. Whole-exome sequencing (WES) of tumor tissue, organoids, and peripheral blood mononuclear cells was performed to identify somatic mutations.
Project description:In our study, we aimed to investigate adaptive processes of tumors under treatment and therefore, generated PDAC patient-derived organoids (PDOs) and 2D cell lines before and after chemotherapy. We enrolled a patient with borderline resectable PDAC who received neoadjuvant FOLFIRINOX. Endoscopic fine needle (pre-FFX) and surgical biopsies (post-FFX) were used to generate PDOs and 2D cells. Whole exome sequencing (WES) and RNA sequencing data of the pre-FFX and post-FFX organoids were compared in order to evaluate the genetic landscape and PDAC subtypes. Although transcriptional subtyping classified both PDOs as classical PDAC, gene set enrichment analysis (GSEA) revealed a reduced pathway activation linked to the basal-like phenotype such as KRAS signaling in the post-FFX organoids. WES did not show major differences in the genetic landscape of the tumor pre- and post-FFX induction suggesting a plasticity process rather than a clonal selection during chemotherapy. 2D cells were subjected to an unbiased automated drug screening of 415 compounds to investigate FFX-induced vulnerabilities. Top targets such as MEK inhibitors were validated manually in the 2D cells and organoids and an increased sensitivity was observed in the post-FFX cells. Thus, integrating functional layers into personalized medicine allows to identify chemotherapy-induced vulnerabilities as potent targeted therapy options in PDAC.