Project description:Microarray analysis of 28 brain metastasis samples from lung adenocarcinoma patients. 28 brain metastasis samples: 19 from Marc Ladanyi 9 from William L. Gerald
Project description:Brain metastasis developed in nearly 40% of lung adenocarcinoma (LUAD) patients diagnosed with distant metastasis. There is lack of transcriptomic data of brain lesions from human lung adenocarcinoma patients. As part of the project to understanding the tumor microenvironment in brain metastasis of LUAD patients, we performed bulk RNA analysis on brain metastases from 6 LUAD patients. In order to understand the tumor intrinsic factors that potential shape the tumor microenvironment, we compared these data with bulk RNA sequencing data from 14 early stage and 11 late stage primary LUAD tumor from TCGA database. Pathway expression analysis showed a downregulation of pro-inflammatory signals in brain metastasis and upregulation of DNA synthesis and oxidative phosphorylation pathways related to rapid proliferation in brain lesions.
Project description:Lung cancer is a leading cause of cancer-related deaths worldwide, with brain metastasis occurring in approximately 30-55% of patients, particularly in lung adenocarcinoma. Due to the challenges in obtaining genuine brain metastasis tumor cells, researchers commonly use nude mouse models to establish brain metastasis cell lines, though traditional methods have limitations such as high costs, lengthy timeframes, and the need for specialized imaging equipment. To address these issues, we developed an improved approach by performing low cell number circulating intracranial injections (500-4000 cells) in nude mice, successfully establishing the H1975-BM1, BM2, and BM3 cell lines. Through RNA sequencing and bioinformatics analyses, we identified transcriptomic differences among these cell lines, revealing that H1975-BM1 cells primarily exhibit stem cell function and migration characteristics, while H1975-BM3 cells display enhanced chemotaxis, cell adhesion, and cytokine secretion associated with interactions. Experimental validation, including Transwell assays, CCK8, cell adhesion assays, and subcutaneous tumor implantation in nude mice, further confirmed these findings, with H1975-BM3 forming larger tumors and a more pronounced secretion cystic cavity. In conclusion, our improved methodology successfully established high-confidence brain metastasis lung adenocarcinoma cell lines, elucidating distinct transcriptomic and functional characteristics at different stages of brain metastasis progression.
Project description:Brain metastases are common in lung adenocarcinoma (LUAD) patients, and by far, the metastasis mechanisms are not fully understood. We performed a comprehensive single-cell level transcriptomic analysis on one LUAD patient with CTC, primary tumor tissue and metastatic tumor tissue using scRNA-seq approach to identify metastasis related biomarkers. Further scRNA-seq were performed on 7 patients to validate the cancer metastatic hallmark. with single cells collected from either metastatic or primary LUAD tissues. we obtained a more comprehensive picture over lung cancer metastasis in the single-cell level, giving a new perspective to the role of RAC1 in the LUAD brain metastasis, and related pathways to participate in the metastasis process.
Project description:Brain metastasis significantly contributes to the failure of targeted therapy in patients with EGFR-mutated lung adenocarcinoma (LUAD). Reduced expression of RBM10 is associated with brain metastasis in these patients. However, the mechanism by which RBM10 affects brain metastasis in EGFR-mutated LUAD remains unclear. Previous studies reveal that RBM10 mutations lead to decreased expression and deregulated splicing at a subset of junctions, primarily through exon skipping.
Project description:Background: Claudin-1(CLDN1), one of the key components of tight junction proteins, was found to be down-regulated in human lung adenocarcinomas. This study we investigated the clinical significance of CLDN1 expression in lung adenocarcinoma patients and its role in cancer progression. Method: CLDN1 mRNA expression was measured in tumor specimens from 51 patients with lung adenocarcinoma. CLDN1 protein expression was also examined by immunohistochemistry on specimens from an independent cohort of 67 lung adenocarcinoma patients. CLDN1 and cancer cell migration, invasion, and in vivo metastasis were studied by compared CLDN1 overexpressed, specific shRNA knockdown cells and controls. The Affymetrix oligonucleotide microarray analysis was performed to identify CLDN1 downstream genes. Results: Lung adenocarcinoma patients with low expression of CLDN1 mRNA had shorter overall survival (p = 0.032, log-rank test). This result was further confirmed by immunohistochemistry of CLDN1 protein expression in an independent cohort of lung adenocarcinoma patients (p=0.024). Over-expression of CLDN1 inhibited lung adenocarcinoma cell migration, invasion, and in vivo metastasis. Knockdown of the exogenous CLDN1 expression in CLDN1 transfectants can restore the cancer cell invasive and metastatic ability. By using Affymetrix microarray we have identified panel of genes altered by CLDN1 over-expression. CLDN1 can up-regulate several cancer invasion/metastasis suppressors such as CTGF, THBS1, DLC1, OCLN, ZO-1, and also down-regulate invasion/metastasis enhancers such as SPP1, CUTL1, TGF-α, SLC2A3, PGF, which support that CLDN1 may behave as an invasion and metastasis suppressor. Conclusions: CLDN is a cancer invasion and metastasis suppressor. CLDN1 expression is a useful prognostic predictor and a potential drug treatment target for lung adenocarcinoma patients. Keywords: genetic modification
Project description:Molecular programs that mediate normal cell differentiation are required for oncogenesis and tumor cell survival in certain types of cancers. How cell lineage restricted genes specifically influence metastatic progression is poorly defined. In lung cancers, we uncovered an alveolar cell-selective transcriptional program that preferentially correlates with lung adenocarcinoma metastasis. This program is required for epithelial specification in the distal airways and is partially regulated by the lineage transcription factors GATA6 and HOPX. These factors cooperatively restrain the metastatic competence of adenocarcinoma cells, without affecting their survival, through the modulation of alveologenic and invasogenic target genes. Thus, GATA6 and HOPX are critical nodes in a lineage-selective pathway that directly links alveolar cell fate with metastasis suppresion in the lung adenocarcinoma subtype. mRNA profiles of human lung Adenocarcinoma PC9 cell lines infected with lentivirus harboring shRNA of control (Arab1) and shRNA of both GATA6 and HOPX were generated by deep sequencing, in triplicate, using Illumina HiSeq2000.
Project description:Lung cancer is the leading cause of cancer death worldwide. Brain metastasis is a major cause of morbidity and mortality in lung cancer. CDH2 (N-cadherin, a mesenchymal marker in epithelial-mesenchymal transition) and ADAM9 (a member of type I transmembrane proteins) have been reported relating to lung cancer brain metastasis, however, it is still not clear whether any interaction between them to mediate lung cancer brain metastasis. Since microRNAs were discovered to regulate many biological functions and disease processes (e.g., cancer) by down-regulating their target genes, microRNA microarrays were used to identify ADAM9 regulated miRNAs that target CDH2 in aggressive lung cancer cells. Luciferase assays and immunoblotting proved that CDH2 was a target gene of miR-218. The expression of miR-218 was generated from pri-mir-218-1, located in SLIT2, in low invasive lung adenocarcinoma while it was inhibited in aggressive lung adenocarcinoma. Down-regulation of ADAM9 could up-regulate SLIT2 and miR-218, thus down-regulate CDH2 expression. This study elucidated the mechanism of ADAM9 activating CDH2 may be due to release the inhibition of miR-218 on CDH2 in lung adenocarcinoma. For each of the cell lines bm#2, bm#7, and F4, one microarray was analyzed.