1
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Agrawal P, Jain N, Gopalan V, Timon A, Singh A, Rajagopal PS, Hannenhalli S. Network-based approach elucidates critical genes in BRCA subtypes and chemotherapy response in triple negative breast cancer. iScience 2024; 27:109752. [PMID: 38699227 PMCID: PMC11063905 DOI: 10.1016/j.isci.2024.109752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 03/18/2024] [Accepted: 04/12/2024] [Indexed: 05/05/2024] Open
Abstract
Breast cancers (BRCA) exhibit substantial transcriptional heterogeneity, posing a significant clinical challenge. The global transcriptional changes in a disease context, however, are likely mediated by few key genes which reflect disease etiology better than the differentially expressed genes (DEGs). We apply our network-based tool PathExt to 1,059 BRCA tumors across 4 subtypes to identify key mediator genes in each subtype. Compared to conventional differential expression analysis, PathExt-identified genes exhibit greater concordance across tumors, revealing shared and subtype-specific biological processes; better recapitulate BRCA-associated genes in multiple benchmarks, and are more essential in BRCA subtype-specific cell lines. Single-cell transcriptomic analysis reveals a subtype-specific distribution of PathExt-identified genes in multiple cell types from the tumor microenvironment. Application of PathExt to a TNBC chemotherapy response dataset identified subtype-specific key genes and biological processes associated with resistance. We described putative drugs that target key genes potentially mediating drug resistance.
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Affiliation(s)
- Piyush Agrawal
- Cancer Data Science Lab, National Cancer Institute, NIH, Bethesda, MD, USA
| | | | - Vishaka Gopalan
- Cancer Data Science Lab, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Annan Timon
- University of Pennsylvania, Philadelphia, PA, USA
| | - Arashdeep Singh
- Cancer Data Science Lab, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Padma S. Rajagopal
- Cancer Data Science Lab, National Cancer Institute, NIH, Bethesda, MD, USA
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2
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Luo S, Li Z, Liu L, Zhao J, Ge W, Zhang K, Zhou Z, Liu Y. Static magnetic field-induced IL-6 secretion in periodontal ligament stem cells accelerates orthodontic tooth movement. Sci Rep 2024; 14:9851. [PMID: 38684732 PMCID: PMC11059396 DOI: 10.1038/s41598-024-60621-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2024] [Accepted: 04/25/2024] [Indexed: 05/02/2024] Open
Abstract
Static magnetic field (SMF) promoting bone tissue remodeling is a potential non-invasive therapy technique to accelerate orthodontic tooth movement (OTM). The periodontal ligament stem cells (PDLSCs), which are mechanosensitive cells, are essential for force-induced bone remodeling and OTM. However, whether and how the PDLSCs influence the process of inflammatory bone remodeling under mechanical force stimuli in the presence of SMFs remains unclear. In this study, we found that local SMF stimulation significantly enhanced the OTM distance and induced osteoclastogenesis on the compression side of a rat model of OTM. Further experiments with macrophages cultured with supernatants from force-loaded PDLSCs exposed to an SMF showed enhanced osteoclast formation. RNA-seq analysis showed that interleukin-6 (IL-6) was elevated in force-loaded PDLSCs exposed to SMFs. IL-6 expression was also elevated on the pressure side of a rat OTM model with an SMF. The OTM distance induced by an SMF was significantly decreased after injection of the IL-6 inhibitor tocilizumab. These results imply that SMF promotes osteoclastogenesis by inducing force-loaded PDLSCs to secrete the inflammatory cytokine IL-6, which accelerates OTM. This will help to reveal the mechanism of SMF accelerates tooth movement and should be evaluated for application in periodontitis patients.
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Affiliation(s)
- Shitong Luo
- Department of Orthodontics, School and Hospital of Stomatology, Kunming Medical University, 1088 Middle Haiyuan Road, High-Tech Zone, Kunming, 650106, Yunnan, China
- Yunnan Key Laboratory of Stomatology, Kunming, 650106, China
- Department of Orthodontics, Suining Central Hospital, Suining, 629000, China
| | - Zhilian Li
- Department of Orthodontics, School and Hospital of Stomatology, Kunming Medical University, 1088 Middle Haiyuan Road, High-Tech Zone, Kunming, 650106, Yunnan, China
- Yunnan Key Laboratory of Stomatology, Kunming, 650106, China
| | - Lizhiyi Liu
- Department of Orthodontics, School and Hospital of Stomatology, Kunming Medical University, 1088 Middle Haiyuan Road, High-Tech Zone, Kunming, 650106, Yunnan, China
- Yunnan Key Laboratory of Stomatology, Kunming, 650106, China
| | - Juan Zhao
- Department of Pathology, Suining Central Hospital, Suining, 629000, China
| | - Wenbin Ge
- Department of Orthodontics, School and Hospital of Stomatology, Kunming Medical University, 1088 Middle Haiyuan Road, High-Tech Zone, Kunming, 650106, Yunnan, China
- Yunnan Key Laboratory of Stomatology, Kunming, 650106, China
| | - Kun Zhang
- Department of Orthodontics, School and Hospital of Stomatology, Kunming Medical University, 1088 Middle Haiyuan Road, High-Tech Zone, Kunming, 650106, Yunnan, China
- Yunnan Key Laboratory of Stomatology, Kunming, 650106, China
| | - Zhi Zhou
- Department of Orthodontics, Affiliated Hospital of Yunnan University, Yunnan University, 176 Qingnian Road, Wuhua District, Kunming, 650021, Yunnan, China.
| | - Yali Liu
- Department of Orthodontics, School and Hospital of Stomatology, Kunming Medical University, 1088 Middle Haiyuan Road, High-Tech Zone, Kunming, 650106, Yunnan, China.
- Yunnan Key Laboratory of Stomatology, Kunming, 650106, China.
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3
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López-Martínez A, Santos-Álvarez JC, Velázquez-Enríquez JM, Ramírez-Hernández AA, Vásquez-Garzón VR, Baltierrez-Hoyos R. lncRNA-mRNA Co-Expression and Regulation Analysis in Lung Fibroblasts from Idiopathic Pulmonary Fibrosis. Noncoding RNA 2024; 10:26. [PMID: 38668384 PMCID: PMC11054336 DOI: 10.3390/ncrna10020026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 04/05/2024] [Accepted: 04/13/2024] [Indexed: 04/29/2024] Open
Abstract
Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease marked by abnormal accumulation of extracellular matrix (ECM) due to dysregulated expression of various RNAs in pulmonary fibroblasts. This study utilized RNA-seq data meta-analysis to explore the regulatory network of hub long non-coding RNAs (lncRNAs) and messenger RNAs (mRNAs) in IPF fibroblasts. The meta-analysis unveiled 584 differentially expressed mRNAs (DEmRNA) and 75 differentially expressed lncRNAs (DElncRNA) in lung fibroblasts from IPF. Among these, BCL6, EFNB1, EPHB2, FOXO1, FOXO3, GNAI1, IRF4, PIK3R1, and RXRA were identified as hub mRNAs, while AC008708.1, AC091806.1, AL442071.1, FAM111A-DT, and LINC01989 were designated as hub lncRNAs. Functional characterization revealed involvement in TGF-β, PI3K, FOXO, and MAPK signaling pathways. Additionally, this study identified regulatory interactions between sequences of hub mRNAs and lncRNAs. In summary, the findings suggest that AC008708.1, AC091806.1, FAM111A-DT, LINC01989, and AL442071.1 lncRNAs can regulate BCL6, EFNB1, EPHB2, FOXO1, FOXO3, GNAI1, IRF4, PIK3R1, and RXRA mRNAs in fibroblasts bearing IPF and contribute to fibrosis by modulating crucial signaling pathways such as FoxO signaling, chemical carcinogenesis, longevity regulatory pathways, non-small cell lung cancer, and AMPK signaling pathways.
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Affiliation(s)
- Armando López-Martínez
- Laboratorio de Fibrosis y Cáncer, Facultad de Medicina y Cirugía, Universidad Autónoma Benito Juárez de Oaxaca, Ex Hacienda de Aguilera S/N, Sur, San Felipe del Agua, Oaxaca C.P. 68020, Mexico; (A.L.-M.); (J.C.S.-Á.); (J.M.V.-E.); (A.A.R.-H.); (V.R.V.-G.)
| | - Jovito Cesar Santos-Álvarez
- Laboratorio de Fibrosis y Cáncer, Facultad de Medicina y Cirugía, Universidad Autónoma Benito Juárez de Oaxaca, Ex Hacienda de Aguilera S/N, Sur, San Felipe del Agua, Oaxaca C.P. 68020, Mexico; (A.L.-M.); (J.C.S.-Á.); (J.M.V.-E.); (A.A.R.-H.); (V.R.V.-G.)
| | - Juan Manuel Velázquez-Enríquez
- Laboratorio de Fibrosis y Cáncer, Facultad de Medicina y Cirugía, Universidad Autónoma Benito Juárez de Oaxaca, Ex Hacienda de Aguilera S/N, Sur, San Felipe del Agua, Oaxaca C.P. 68020, Mexico; (A.L.-M.); (J.C.S.-Á.); (J.M.V.-E.); (A.A.R.-H.); (V.R.V.-G.)
| | - Alma Aurora Ramírez-Hernández
- Laboratorio de Fibrosis y Cáncer, Facultad de Medicina y Cirugía, Universidad Autónoma Benito Juárez de Oaxaca, Ex Hacienda de Aguilera S/N, Sur, San Felipe del Agua, Oaxaca C.P. 68020, Mexico; (A.L.-M.); (J.C.S.-Á.); (J.M.V.-E.); (A.A.R.-H.); (V.R.V.-G.)
| | - Verónica Rocío Vásquez-Garzón
- Laboratorio de Fibrosis y Cáncer, Facultad de Medicina y Cirugía, Universidad Autónoma Benito Juárez de Oaxaca, Ex Hacienda de Aguilera S/N, Sur, San Felipe del Agua, Oaxaca C.P. 68020, Mexico; (A.L.-M.); (J.C.S.-Á.); (J.M.V.-E.); (A.A.R.-H.); (V.R.V.-G.)
- CONACYT-Facultad de Medicina y Cirugía, Universidad Autónoma Benito Juárez de Oaxaca, Ex Hacienda de Aguilera S/N, Sur, San Felipe del Agua, Oaxaca C.P. 68020, Mexico
| | - Rafael Baltierrez-Hoyos
- Laboratorio de Fibrosis y Cáncer, Facultad de Medicina y Cirugía, Universidad Autónoma Benito Juárez de Oaxaca, Ex Hacienda de Aguilera S/N, Sur, San Felipe del Agua, Oaxaca C.P. 68020, Mexico; (A.L.-M.); (J.C.S.-Á.); (J.M.V.-E.); (A.A.R.-H.); (V.R.V.-G.)
- CONACYT-Facultad de Medicina y Cirugía, Universidad Autónoma Benito Juárez de Oaxaca, Ex Hacienda de Aguilera S/N, Sur, San Felipe del Agua, Oaxaca C.P. 68020, Mexico
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Parga-Pazos M, Cusimano N, Rábano M, Akhmatskaya E, Vivanco MDM. A Novel Mathematical Approach for Analysis of Integrated Cell-Patient Data Uncovers a 6-Gene Signature Linked to Endocrine Therapy Resistance. J Transl Med 2024; 104:100286. [PMID: 37951307 DOI: 10.1016/j.labinv.2023.100286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 10/17/2023] [Accepted: 11/03/2023] [Indexed: 11/13/2023] Open
Abstract
A significant number of breast cancers develop resistance to hormone therapy. This progression, while posing a major clinical challenge, is difficult to predict. Despite important contributions made by cell models and clinical studies to tackle this problem, both present limitations when taken individually. Experiments with cell models are highly reproducible but do not reflect the indubitable heterogenous landscape of breast cancer. On the other hand, clinical studies account for this complexity but introduce uncontrolled noise due to external factors. Here, we propose a new approach for biomarker discovery that is based on a combined analysis of sequencing data from controlled MCF7 cell experiments and heterogenous clinical samples that include clinical and sequencing information from The Cancer Genome Atlas. Using data from differential gene expression analysis and a Bayesian logistic regression model coupled with an original simulated annealing-type algorithm, we discovered a novel 6-gene signature for stratifying patient response to hormone therapy. The experimental observations and computational analysis built on independent cohorts indicated the superior predictive performance of this gene set over previously known signatures of similar scope. Together, these findings revealed a new gene signature to identify patients with breast cancer with an increased risk of developing resistance to endocrine therapy.
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Affiliation(s)
- Martin Parga-Pazos
- Modelling and Simulation in Life and Materials Sciences, Basque Center for Applied Mathematics, Spain; Cancer Heterogeneity Lab, CIC bioGUNE, Basque Research and Technology Alliance, Derio, Spain
| | - Nicole Cusimano
- Modelling and Simulation in Life and Materials Sciences, Basque Center for Applied Mathematics, Spain
| | - Miriam Rábano
- Cancer Heterogeneity Lab, CIC bioGUNE, Basque Research and Technology Alliance, Derio, Spain
| | - Elena Akhmatskaya
- Modelling and Simulation in Life and Materials Sciences, Basque Center for Applied Mathematics, Spain; IKERBASQUE, Basque Foundation for Science, Bilbao, Spain.
| | - Maria dM Vivanco
- Cancer Heterogeneity Lab, CIC bioGUNE, Basque Research and Technology Alliance, Derio, Spain.
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5
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Trivizakis E, Koutroumpa NM, Souglakos J, Karantanas A, Zervakis M, Marias K. Radiotranscriptomics of non-small cell lung carcinoma for assessing high-level clinical outcomes using a machine learning-derived multi-modal signature. Biomed Eng Online 2023; 22:125. [PMID: 38102586 PMCID: PMC10724973 DOI: 10.1186/s12938-023-01190-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Accepted: 12/07/2023] [Indexed: 12/17/2023] Open
Abstract
BACKGROUND Multi-omics research has the potential to holistically capture intra-tumor variability, thereby improving therapeutic decisions by incorporating the key principles of precision medicine. The purpose of this study is to identify a robust method of integrating features from different sources, such as imaging, transcriptomics, and clinical data, to predict the survival and therapy response of non-small cell lung cancer patients. METHODS 2996 radiomics, 5268 transcriptomics, and 8 clinical features were extracted from the NSCLC Radiogenomics dataset. Radiomics and deep features were calculated based on the volume of interest in pre-treatment, routine CT examinations, and then combined with RNA-seq and clinical data. Several machine learning classifiers were used to perform survival analysis and assess the patient's response to adjuvant chemotherapy. The proposed analysis was evaluated on an unseen testing set in a k-fold cross-validation scheme. Score- and concatenation-based multi-omics were used as feature integration techniques. RESULTS Six radiomics (elongation, cluster shade, entropy, variance, gray-level non-uniformity, and maximal correlation coefficient), six deep features (NasNet-based activations), and three transcriptomics (OTUD3, SUCGL2, and RQCD1) were found to be significant for therapy response. The examined score-based multi-omic improved the AUC up to 0.10 on the unseen testing set (0.74 ± 0.06) and the balance between sensitivity and specificity for predicting therapy response for 106 patients, resulting in less biased models and improving upon the either highly sensitive or highly specific single-source models. Six radiomics (kurtosis, GLRLM- and GLSZM-based non-uniformity from images with no filtering, biorthogonal, and daubechies wavelets), seven deep features (ResNet-based activations), and seven transcriptomics (ELP3, ZZZ3, PGRMC2, TRAK1, ATIC, USP7, and PNPLA2) were found to be significant for the survival analysis. Accordingly, the survival analysis for 115 patients was also enhanced up to 0.20 by the proposed score-based multi-omics in terms of the C-index (0.79 ± 0.03). CONCLUSIONS Compared to single-source models, multi-omics integration has the potential to improve prediction performance, increase model stability, and reduce bias for both treatment response and survival analysis.
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Affiliation(s)
- Eleftherios Trivizakis
- Computational Biomedicine Laboratory (CBML), Foundation for Research and Technology Hellas (FORTH), 70013, Heraklion, Greece.
- Medical School, University of Crete, 71003, Heraklion, Greece.
| | - Nikoletta-Maria Koutroumpa
- Medical School, University of Crete, 71003, Heraklion, Greece
- School of Electrical and Computer Engineering, Technical University of Crete, 73100, Chania, Greece
| | - John Souglakos
- Laboratory of Translational Oncology, Medical School, University of Crete, 71003, Heraklion, Greece
- Department of Medical Oncology, University Hospital of Heraklion, 71500, Heraklion, Greece
| | - Apostolos Karantanas
- Computational Biomedicine Laboratory (CBML), Foundation for Research and Technology Hellas (FORTH), 70013, Heraklion, Greece
- Department of Radiology, Medical School, University of Crete, 71003, Heraklion, Greece
| | - Michalis Zervakis
- School of Electrical and Computer Engineering, Technical University of Crete, 73100, Chania, Greece
| | - Kostas Marias
- Computational Biomedicine Laboratory (CBML), Foundation for Research and Technology Hellas (FORTH), 70013, Heraklion, Greece
- Department of Electrical and Computer Engineering, Hellenic Mediterranean University, 71410, Heraklion, Greece
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6
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Maden SK, Kwon SH, Huuki-Myers LA, Collado-Torres L, Hicks SC, Maynard KR. Challenges and opportunities to computationally deconvolve heterogeneous tissue with varying cell sizes using single-cell RNA-sequencing datasets. Genome Biol 2023; 24:288. [PMID: 38098055 PMCID: PMC10722720 DOI: 10.1186/s13059-023-03123-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2023] [Accepted: 11/24/2023] [Indexed: 12/17/2023] Open
Abstract
Deconvolution of cell mixtures in "bulk" transcriptomic samples from homogenate human tissue is important for understanding disease pathologies. However, several experimental and computational challenges impede transcriptomics-based deconvolution approaches using single-cell/nucleus RNA-seq reference atlases. Cells from the brain and blood have substantially different sizes, total mRNA, and transcriptional activities, and existing approaches may quantify total mRNA instead of cell type proportions. Further, standards are lacking for the use of cell reference atlases and integrative analyses of single-cell and spatial transcriptomics data. We discuss how to approach these key challenges with orthogonal "gold standard" datasets for evaluating deconvolution methods.
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Affiliation(s)
- Sean K Maden
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
| | - Sang Ho Kwon
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD, USA
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD, USA
| | - Louise A Huuki-Myers
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD, USA
| | - Leonardo Collado-Torres
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD, USA
| | - Stephanie C Hicks
- Department of Biostatistics, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA.
- Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD, USA.
- Center for Computational Biology, Johns Hopkins University, Baltimore, MD, USA.
- Malone Center for Engineering in Healthcare, Johns Hopkins University, Baltimore, MD, USA.
| | - Kristen R Maynard
- Lieber Institute for Brain Development, Johns Hopkins Medical Campus, Baltimore, MD, USA.
- The Solomon H. Snyder Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, MD, USA.
- Department of Psychiatry and Behavioral Sciences, Johns Hopkins School of Medicine, Baltimore, MD, USA.
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7
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Prada-Luengo I, Schuster V, Liang Y, Terkelsen T, Sora V, Krogh A. N-of-one differential gene expression without control samples using a deep generative model. Genome Biol 2023; 24:263. [PMID: 37974217 PMCID: PMC10655485 DOI: 10.1186/s13059-023-03104-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 11/06/2023] [Indexed: 11/19/2023] Open
Abstract
Differential analysis of bulk RNA-seq data often suffers from lack of good controls. Here, we present a generative model that replaces controls, trained solely on healthy tissues. The unsupervised model learns a low-dimensional representation and can identify the closest normal representation for a given disease sample. This enables control-free, single-sample differential expression analysis. In breast cancer, we demonstrate how our approach selects marker genes and outperforms a state-of-the-art method. Furthermore, significant genes identified by the model are enriched in driver genes across cancers. Our results show that the in silico closest normal provides a more favorable comparison than control samples.
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Affiliation(s)
- Iñigo Prada-Luengo
- Department of Computer Science, University of Copenhagen, Copenhagen, Denmark
| | - Viktoria Schuster
- Center for Health Data Science, University of Copenhagen, Copenhagen, Denmark
| | - Yuhu Liang
- Department of Computer Science, University of Copenhagen, Copenhagen, Denmark
| | - Thilde Terkelsen
- Center for Health Data Science, University of Copenhagen, Copenhagen, Denmark
| | - Valentina Sora
- Department of Computer Science, University of Copenhagen, Copenhagen, Denmark
| | - Anders Krogh
- Department of Computer Science, University of Copenhagen, Copenhagen, Denmark.
- Center for Health Data Science, University of Copenhagen, Copenhagen, Denmark.
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8
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Błoch M, Gasperowicz P, Gerus S, Rasiewicz K, Lebioda A, Skiba P, Płoski R, Patkowski D, Karpiński P, Śmigiel R. Epigenetic Findings in Twins with Esophageal Atresia. Genes (Basel) 2023; 14:1822. [PMID: 37761962 PMCID: PMC10531363 DOI: 10.3390/genes14091822] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2023] [Revised: 09/14/2023] [Accepted: 09/16/2023] [Indexed: 09/29/2023] Open
Abstract
Esophageal atresia (EA) is the most common malformation of the upper gastrointestinal tract. The estimated incidence of EA is 1 in 3500 births. EA is more frequently observed in boys and in twins. The exact cause of isolated EA remains unknown; a multifactorial etiology, including epigenetic gene expression modifications, is considered. The study included six pairs of twins (three pairs of monozygotic twins and three pairs of dizygotic twins) in which one child was born with EA as an isolated defect, while the other twin was healthy. DNA samples were obtained from the blood and esophageal tissue of the child with EA as well as from the blood of the healthy twin. The reduced representation bisulfite sequencing (RRBS) technique was employed for a whole-genome methylation analysis. The analyses focused on comparing the CpG island methylation profiles between patients with EA and their healthy siblings. Hypermethylation in the promoters of 219 genes and hypomethylation in the promoters of 78 genes were observed. A pathway enrichment analysis revealed the statistically significant differences in methylation profile of 10 hypermethylated genes in the Rho GTPase pathway, previously undescribed in the field of EA (ARHGAP36, ARHGAP4, ARHGAP6, ARHGEF6, ARHGEF9, FGD1, GDI1, MCF2, OCRL, and STARD8).
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Affiliation(s)
- Michal Błoch
- Department of Family and Pediatric Nursing, Wroclaw Medical University, 51-618 Wroclaw, Poland;
| | - Piotr Gasperowicz
- Department of Medical Genetics, Medical University of Warsaw, 04-768 Warsaw, Poland
| | - Sylwester Gerus
- Department of Pediatric Surgery and Urology, Medical University of Wroclaw, 51-618 Wroclaw, Poland; (S.G.)
| | - Katarzyna Rasiewicz
- Department of Pediatric Surgery and Urology, Medical University of Wroclaw, 51-618 Wroclaw, Poland; (S.G.)
| | - Arleta Lebioda
- Division of Molecular Techniques, Department of Forensic Medicine, Wroclaw Medical University, 51-618 Wroclaw, Poland
| | - Pawel Skiba
- Department of Genetics, Wroclaw Medical University, 51-618 Wroclaw, Poland
| | - Rafal Płoski
- Department of Medical Genetics, Medical University of Warsaw, 04-768 Warsaw, Poland
| | - Dariusz Patkowski
- Department of Pediatric Surgery and Urology, Medical University of Wroclaw, 51-618 Wroclaw, Poland; (S.G.)
| | - Pawel Karpiński
- Department of Genetics, Wroclaw Medical University, 51-618 Wroclaw, Poland
| | - Robert Śmigiel
- Department of Pediatrics, Endocrinology, Diabetology and Metabolic Diseases, Medical University of Wroclaw, 51-618 Wroclaw, Poland
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9
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Agrawal P, Jain N, Gopalan V, Timon A, Singh A, Rajagopal PS, Hannenhalli S. Network-based approach elucidates critical genes in BRCA subtypes and chemotherapy response in Triple Negative Breast Cancer. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.05.21.541618. [PMID: 37425784 PMCID: PMC10327220 DOI: 10.1101/2023.05.21.541618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/11/2023]
Abstract
Breast cancers exhibit substantial transcriptional heterogeneity, posing a significant challenge to the prediction of treatment response and prognostication of outcomes. Especially, translation of TNBC subtypes to the clinic remains a work in progress, in part because of a lack of clear transcriptional signatures distinguishing the subtypes. Our recent network-based approach, PathExt, demonstrates that global transcriptional changes in a disease context are likely mediated by a small number of key genes, and these mediators may better reflect functional or translationally relevant heterogeneity. We apply PathExt to 1059 BRCA tumors and 112 healthy control samples across 4 subtypes to identify frequent, key-mediator genes in each BRCA subtype. Compared to conventional differential expression analysis, PathExt-identified genes (1) exhibit greater concordance across tumors, revealing shared as well as BRCA subtype-specific biological processes, (2) better recapitulate BRCA-associated genes in multiple benchmarks, and (3) exhibit greater dependency scores in BRCA subtype-specific cancer cell lines. Single cell transcriptomes of BRCA subtype tumors reveal a subtype-specific distribution of PathExt-identified genes in multiple cell types from the tumor microenvironment. Application of PathExt to a TNBC chemotherapy response dataset identified TNBC subtype-specific key genes and biological processes associated with resistance. We described putative drugs that target top novel genes potentially mediating drug resistance. Overall, PathExt applied to breast cancer refines previous views of gene expression heterogeneity and identifies potential mediators of TNBC subtypes, including potential therapeutic targets.
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Affiliation(s)
- Piyush Agrawal
- Cancer Data Science Lab, National Cancer Institute, NIH, Bethesda, MD, USA
| | | | - Vishaka Gopalan
- Cancer Data Science Lab, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Annan Timon
- University of Pennsylvania, Philadelphia, PA, USA
| | - Arashdeep Singh
- Cancer Data Science Lab, National Cancer Institute, NIH, Bethesda, MD, USA
| | - Padma S Rajagopal
- Cancer Data Science Lab, National Cancer Institute, NIH, Bethesda, MD, USA
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Khalafiyan A, Emadi-Baygi M, Wolfien M, Salehzadeh-Yazdi A, Nikpour P. Construction of a three-component regulatory network of transcribed ultraconserved regions for the identification of prognostic biomarkers in gastric cancer. J Cell Biochem 2023; 124:396-408. [PMID: 36748954 DOI: 10.1002/jcb.30373] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 01/04/2023] [Accepted: 01/09/2023] [Indexed: 02/08/2023]
Abstract
Altered expression and functional roles of the transcribed ultraconserved regions (T-UCRs), as genomic sequences with 100% conservation between the genomes of human, mouse, and rat, in the pathophysiology of neoplasms has already been investigated. Nevertheless, the relevance of the functions for T-UCRs in gastric cancer (GC) is still the subject of inquiry. In the current study, we first used a genome-wide profiling approach to analyze the expression of T-UCRs in GC patients. Then, we constructed a three-component regulatory network and investigated potential diagnostic and prognostic values of the T-UCRs. The Cancer Genome Atlas Stomach Adenocarcinoma (TCGA-STAD) dataset was used as a resource for the RNA-sequencing data. FeatureCounts was utilized to quantify the number of reads mapped to each T-UCR. Differential expression analysis was then conducted using DESeq2. In the following, interactions between T-UCRs, microRNAs (miRNAs), and messenger RNAs (mRNAs) were combined into a three-component network. Enrichment analyses were performed and a protein-protein interaction (PPI) network was constructed. The R Survival package was utilized to identify survival-related significantly differentially expressed T-UCRs (DET-UCRs). Using an in-house cohort of GC tissues, expression of two DET-UCRs was furthermore experimentally verified. Our results showed that several T-UCRs were dysregulated in TCGA-STAD tumoral samples compared to nontumoral counterparts. The three-component network was constructed which composed of DET-UCRs, miRNAs, and mRNAs nodes. Functional enrichment and PPI network analyses revealed important enriched signaling pathways and gene ontologies such as "pathway in cancer" and regulation of cell proliferation and apoptosis. Five T-UCRs were significantly correlated with the overall survival of GC patients. While no expression of uc.232 was observed in our in-house cohort of GC tissues, uc.343 showed an increased expression, although not statistically significant, in gastric tumoral tissues. The constructed three-component regulatory network of T-UCRs in GC presents a comprehensive understanding of the underlying gene expression regulation processes involved in tumor development and can serve as a basis to investigate potential prognostic biomarkers and therapeutic targets.
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Affiliation(s)
- Anis Khalafiyan
- Department of Genetics and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Modjtaba Emadi-Baygi
- Department of Genetics, Faculty of Basic Sciences, Shahrekord University, Shahrekord, Iran
| | - Markus Wolfien
- Department of System Biology and Bioinformatics, University of Rostock, Rostock, Germany
- Center for Medical Informatics, Dresden, Germany
| | - Ali Salehzadeh-Yazdi
- Department of Life Sciences and Chemistry, Jacobs University Bremen, Bremen, Germany
| | - Parvaneh Nikpour
- Department of Genetics and Molecular Biology, Faculty of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran
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11
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Le Priol C, Azencott CA, Gidrol X. Detection of genes with differential expression dispersion unravels the role of autophagy in cancer progression. PLoS Comput Biol 2023; 19:e1010342. [PMID: 36893104 PMCID: PMC9997931 DOI: 10.1371/journal.pcbi.1010342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Accepted: 02/09/2023] [Indexed: 03/10/2023] Open
Abstract
The majority of gene expression studies focus on the search for genes whose mean expression is different between two or more populations of samples in the so-called "differential expression analysis" approach. However, a difference in variance in gene expression may also be biologically and physiologically relevant. In the classical statistical model used to analyze RNA-sequencing (RNA-seq) data, the dispersion, which defines the variance, is only considered as a parameter to be estimated prior to identifying a difference in mean expression between conditions of interest. Here, we propose to evaluate four recently published methods, which detect differences in both the mean and dispersion in RNA-seq data. We thoroughly investigated the performance of these methods on simulated datasets and characterized parameter settings to reliably detect genes with a differential expression dispersion. We applied these methods to The Cancer Genome Atlas datasets. Interestingly, among the genes with an increased expression dispersion in tumors and without a change in mean expression, we identified some key cellular functions, most of which were related to catabolism and were overrepresented in most of the analyzed cancers. In particular, our results highlight autophagy, whose role in cancerogenesis is context-dependent, illustrating the potential of the differential dispersion approach to gain new insights into biological processes and to discover new biomarkers.
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Affiliation(s)
- Christophe Le Priol
- Univ. Grenoble Alpes, INSERM, CEA-IRIG, Biomics, Grenoble, France
- * E-mail: (CLP); (XG)
| | - Chloé-Agathe Azencott
- Center for Computational Biology, Mines ParisTech, PSL Research University, Paris, France
- Institut Curie, Paris, France
- INSERM U900, Paris, France
| | - Xavier Gidrol
- Univ. Grenoble Alpes, INSERM, CEA-IRIG, Biomics, Grenoble, France
- * E-mail: (CLP); (XG)
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12
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Päll T, Luidalepp H, Tenson T, Maiväli Ü. A field-wide assessment of differential expression profiling by high-throughput sequencing reveals widespread bias. PLoS Biol 2023; 21:e3002007. [PMID: 36862747 PMCID: PMC10013925 DOI: 10.1371/journal.pbio.3002007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 03/14/2023] [Accepted: 01/20/2023] [Indexed: 03/03/2023] Open
Abstract
We assess inferential quality in the field of differential expression profiling by high-throughput sequencing (HT-seq) based on analysis of datasets submitted from 2008 to 2020 to the NCBI GEO data repository. We take advantage of the parallel differential expression testing over thousands of genes, whereby each experiment leads to a large set of p-values, the distribution of which can indicate the validity of assumptions behind the test. From a well-behaved p-value set π0, the fraction of genes that are not differentially expressed can be estimated. We found that only 25% of experiments resulted in theoretically expected p-value histogram shapes, although there is a marked improvement over time. Uniform p-value histogram shapes, indicative of <100 actual effects, were extremely few. Furthermore, although many HT-seq workflows assume that most genes are not differentially expressed, 37% of experiments have π0-s of less than 0.5, as if most genes changed their expression level. Most HT-seq experiments have very small sample sizes and are expected to be underpowered. Nevertheless, the estimated π0-s do not have the expected association with N, suggesting widespread problems of experiments with controlling false discovery rate (FDR). Both the fractions of different p-value histogram types and the π0 values are strongly associated with the differential expression analysis program used by the original authors. While we could double the proportion of theoretically expected p-value distributions by removing low-count features from the analysis, this treatment did not remove the association with the analysis program. Taken together, our results indicate widespread bias in the differential expression profiling field and the unreliability of statistical methods used to analyze HT-seq data.
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Affiliation(s)
- Taavi Päll
- Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | | | - Tanel Tenson
- Institute of Technology, University of Tartu, Tartu, Estonia
| | - Ülo Maiväli
- Institute of Technology, University of Tartu, Tartu, Estonia
- * E-mail:
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13
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The involvement of collagen family genes in tumor enlargement of gastric cancer. Sci Rep 2023; 13:100. [PMID: 36596829 PMCID: PMC9810739 DOI: 10.1038/s41598-022-25061-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Accepted: 11/24/2022] [Indexed: 01/05/2023] Open
Abstract
Extracellular matrix (ECM) not only serves as a support for tumor cell but also regulates cell-cell or cell-matrix cross-talks. Collagens are the most abundant proteins in ECM. Several studies have found that certain collagen genes were overexpressed in gastric cancer (GC) tissues and might serve as potential biomarkers and therapeutic targets in GC patients. However, the expression patterns of all collagen family genes in GC tissue and their functions are still not clear. With RNA sequencing (RNA-Seq) data, microarray data, and corresponding clinical data obtained from TCGA, GTEx, and GEO databases, bioinformatics analyses were performed to investigate the correlation between the expression patterns of collagen family genes and GC progression. We found that quite many of the collagen family genes were overexpressed in GC tissues. The increase in mRNA expression of most of these overexpressed collagen genes happened between T1 and T2 stage, which indicates the significance of collagens in tumor enlargement of GC. Notably, the mRNA expressions of these differentially expressed collagens genes were highly positively correlated. The elevated expression of a large number of collagen genes in early T stage might greatly change the composition and structure organization of ECM, contributing to ECM remodeling in GC progression.
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14
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Keel BN, Lindholm-Perry AK. Recent developments and future directions in meta-analysis of differential gene expression in livestock RNA-Seq. Front Genet 2022; 13:983043. [PMID: 36199583 PMCID: PMC9527320 DOI: 10.3389/fgene.2022.983043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Accepted: 08/24/2022] [Indexed: 11/13/2022] Open
Abstract
Decreases in the costs of high-throughput sequencing technologies have led to continually increasing numbers of livestock RNA-Seq studies in the last decade. Although the number of studies has increased dramatically, most livestock RNA-Seq experiments are limited by cost to a small number of biological replicates. Meta-analysis procedures can be used to integrate and jointly analyze data from multiple independent studies. Meta-analyses increase the sample size, which in turn increase both statistical power and robustness of the results. In this work, we discuss cutting edge approaches to combining results from multiple independent RNA-Seq studies to improve livestock transcriptomics research. We review currently published RNA-Seq meta-analyses in livestock, describe many of the key issues specific to RNA-Seq meta-analysis in livestock species, and discuss future perspectives.
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15
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Samadi P, Soleimani M, Nouri F, Rahbarizadeh F, Najafi R, Jalali A. An integrative transcriptome analysis reveals potential predictive, prognostic biomarkers and therapeutic targets in colorectal cancer. BMC Cancer 2022; 22:835. [PMID: 35907803 PMCID: PMC9339198 DOI: 10.1186/s12885-022-09931-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 07/25/2022] [Indexed: 12/09/2022] Open
Abstract
BACKGROUND A deep understanding of potential molecular biomarkers and therapeutic targets related to the progression of colorectal cancer (CRC) from early stages to metastasis remain mostly undone. Moreover, the regulation and crosstalk among different cancer-driving molecules including messenger RNAs (mRNAs), long non-coding RNAs (lncRNAs) and micro-RNAs (miRNAs) in the transition from stage I to stage IV remain to be clarified, which is the aim of this study. METHODS We carried out two separate differential expression analyses for two different sets of samples (stage-specific samples and tumor/normal samples). Then, by the means of robust dataset analysis we identified distinct lists of differently expressed genes (DEGs) for Robust Rank Aggregation (RRA) and weighted gene co-expression network analysis (WGCNA). Then, comprehensive computational systems biology analyses including mRNA-miRNA-lncRNA regulatory network, survival analysis and machine learning algorithms were also employed to achieve the aim of this study. Finally, we used clinical samples to carry out validation of a potential and novel target in CRC. RESULTS We have identified the most significant stage-specific DEGs by combining distinct results from RRA and WGCNA. After finding stage-specific DEGs, a total number of 37 DEGs were identified to be conserved across all stages of CRC (conserved DEGs). We also found DE-miRNAs and DE-lncRNAs highly associated to these conserved DEGs. Our systems biology approach led to the identification of several potential therapeutic targets, predictive and prognostic biomarkers, of which lncRNA LINC00974 shown as an important and novel biomarker. CONCLUSIONS Findings of the present study provide new insight into CRC pathogenesis across all stages, and suggests future assessment of the functional role of lncRNA LINC00974 in the development of CRC.
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Affiliation(s)
- Pouria Samadi
- Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Meysam Soleimani
- Department of Pharmaceutical Biotechnology, School of Pharmacy, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Fatemeh Nouri
- Department of Pharmaceutical Biotechnology, School of Pharmacy, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Fatemeh Rahbarizadeh
- Department of Medical Biotechnology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Rezvan Najafi
- Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran
| | - Akram Jalali
- Research Center for Molecular Medicine, Hamadan University of Medical Sciences, Hamadan, Iran.
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16
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Kołat D, Kałuzińska Ż, Bednarek AK, Płuciennik E. Determination of WWOX Function in Modulating Cellular Pathways Activated by AP-2α and AP-2γ Transcription Factors in Bladder Cancer. Cells 2022; 11:cells11091382. [PMID: 35563688 PMCID: PMC9106060 DOI: 10.3390/cells11091382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 04/16/2022] [Accepted: 04/18/2022] [Indexed: 02/07/2023] Open
Abstract
Following the invention of high-throughput sequencing, cancer research focused on investigating disease-related alterations, often inadvertently omitting tumor heterogeneity. This research was intended to limit the impact of heterogeneity on conclusions related to WWOX/AP-2α/AP-2γ in bladder cancer which differently influenced carcinogenesis. The study examined the signaling pathways regulated by WWOX-dependent AP-2 targets in cell lines as biological replicates using high-throughput sequencing. RT-112, HT-1376 and CAL-29 cell lines were subjected to two stable lentiviral transductions. Following CAGE-seq and differential expression analysis, the most important genes were identified and functionally annotated. Western blot was performed to validate the selected observations. The role of genes in biological processes was assessed and networks were visualized. Ultimately, principal component analysis was performed. The studied genes were found to be implicated in MAPK, Wnt, Ras, PI3K-Akt or Rap1 signaling. Data from pathways were collected, explaining the differences/similarities between phenotypes. FGFR3, STAT6, EFNA1, GSK3B, PIK3CB and SOS1 were successfully validated at the protein level. Afterwards, a definitive network was built using 173 genes. Principal component analysis revealed that the various expression of these genes explains the phenotypes. In conclusion, the current study certified that the signaling pathways regulated by WWOX and AP-2α have more in common than that regulated by AP-2γ. This is because WWOX acts as an EMT inhibitor, AP-2γ as an EMT enhancer while AP-2α as a MET inducer. Therefore, the relevance of AP-2γ in targeted therapy is now more evident. Some of the differently regulated genes can find application in bladder cancer treatment.
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Deep Radiotranscriptomics of Non-Small Cell Lung Carcinoma for Assessing Molecular and Histology Subtypes with a Data-Driven Analysis. Diagnostics (Basel) 2021; 11:diagnostics11122383. [PMID: 34943617 PMCID: PMC8700168 DOI: 10.3390/diagnostics11122383] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2021] [Revised: 12/15/2021] [Accepted: 12/16/2021] [Indexed: 11/17/2022] Open
Abstract
Radiogenomic and radiotranscriptomic studies have the potential to pave the way for a holistic decision support system built on genomics, transcriptomics, radiomics, deep features and clinical parameters to assess treatment evaluation and care planning. The integration of invasive and routine imaging data into a common feature space has the potential to yield robust models for inferring the drivers of underlying biological mechanisms. In this non-small cell lung carcinoma study, a multi-omics representation comprised deep features and transcriptomics was evaluated to further explore the synergetic and complementary properties of these diverse multi-view data sources by utilizing data-driven machine learning models. The proposed deep radiotranscriptomic analysis is a feature-based fusion that significantly enhances sensitivity by up to 0.174 and AUC by up to 0.22, compared to the baseline single source models, across all experiments on the unseen testing set. Additionally, a radiomics-based fusion was also explored as an alternative methodology yielding radiomic signatures that are comparable to several previous publications in the field of radiogenomics. Furthermore, the machine learning multi-omics analysis based on deep features and transcriptomics achieved an AUC performance of up to 0.831 ± 0.09/0.925 ± 0.04 for the examined molecular and histology subtypes analysis, respectively. The clinical impact of such high-performing models can add prognostic value and lead to optimal treatment assessment by targeting specific oncogenes, namely the response of tyrosine kinase inhibitors of EGFR mutated or predicting the chemotherapy resistance of KRAS mutated tumors.
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18
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Cui W, Xue H, Geng Y, Zhang J, Liang Y, Tian X, Wang Q. Effect of high variation in transcript expression on identifying differentially expressed genes in RNA-seq analysis. Ann Hum Genet 2021; 85:235-244. [PMID: 34341986 DOI: 10.1111/ahg.12441] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2021] [Revised: 07/04/2021] [Accepted: 07/15/2021] [Indexed: 12/13/2022]
Abstract
Great efforts have been made on the algorithms that deal with RNA-seq data to enhance the accuracy and efficiency of differential expression (DE) analysis. However, no consensus has been reached on the proper threshold values of fold change and adjusted p-value for filtering differentially expressed genes (DEGs). It is generally believed that the more stringent the filtering threshold, the more reliable the result of a DE analysis. Nevertheless, by analyzing the impact of both adjusted p-value and fold change thresholds on DE analyses, with RNA-seq data obtained for three different cancer types from the Cancer Genome Atlas (TCGA) database, we found that, for a given sample size, the reproducibility of DE results became poorer when more stringent thresholds were applied. No matter which threshold level was applied, the overlap rates of DEGs were generally lower for small sample sizes than for large sample sizes. The raw read count analysis demonstrated that the transcript expression of the same gene in different samples, whether in tumor groups or in normal groups, showed high variations, which resulted in a drastic fluctuation in fold change values and adjustedp-values when different sets of samples were used. Overall, more stringent thresholds did not yield more reliable DEGs due to high variations in transcript expression; the reliability of DEGs obtained with small sample sizes was more susceptible to these variations. Therefore, less stringent thresholds are recommended for screening DEGs. Moreover, large sample sizes should be considered in RNA-seq experimental designs to reduce the interfering effect of variations in transcript expression on DEG identification.
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Affiliation(s)
- Weitong Cui
- Key Laboratory of Biomedical Engineering & Technology of Shandong High School, Qilu Medical University, Zibo, P. R. China
| | - Huaru Xue
- Key Laboratory of Biomedical Engineering & Technology of Shandong High School, Qilu Medical University, Zibo, P. R. China
| | - Yifan Geng
- Key Laboratory of Biomedical Engineering & Technology of Shandong High School, Qilu Medical University, Zibo, P. R. China.,Xuzhou Medical University, Xuzhou, P. R. China
| | - Jing Zhang
- Key Laboratory of Biomedical Engineering & Technology of Shandong High School, Qilu Medical University, Zibo, P. R. China
| | - Yajun Liang
- Key Laboratory of Biomedical Engineering & Technology of Shandong High School, Qilu Medical University, Zibo, P. R. China
| | - Xuewen Tian
- Shandong Sport University, Jinan, P. R. China
| | - Qinglu Wang
- Key Laboratory of Biomedical Engineering & Technology of Shandong High School, Qilu Medical University, Zibo, P. R. China.,Shandong Sport University, Jinan, P. R. China
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Savino A, De Marzo N, Provero P, Poli V. Meta-Analysis of Microdissected Breast Tumors Reveals Genes Regulated in the Stroma but Hidden in Bulk Analysis. Cancers (Basel) 2021; 13:3371. [PMID: 34282769 PMCID: PMC8268805 DOI: 10.3390/cancers13133371] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2021] [Revised: 06/22/2021] [Accepted: 06/29/2021] [Indexed: 02/06/2023] Open
Abstract
Transcriptome data provide a valuable resource for the study of cancer molecular mechanisms, but technical biases, sample heterogeneity, and small sample sizes result in poorly reproducible lists of regulated genes. Additionally, the presence of multiple cellular components contributing to cancer development complicates the interpretation of bulk transcriptomic profiles. To address these issues, we collected 48 microarray datasets derived from laser capture microdissected stroma or epithelium in breast tumors and performed a meta-analysis identifying robust lists of differentially expressed genes. This was used to create a database with carefully harmonized metadata that we make freely available to the research community. As predicted, combining the results of multiple datasets improved statistical power. Moreover, the separate analysis of stroma and epithelium allowed the identification of genes with different contributions in each compartment, which would not be detected by bulk analysis due to their distinct regulation in the two compartments. Our method can be profitably used to help in the discovery of biomarkers and the identification of functionally relevant genes in both the stroma and the epithelium. This database was made to be readily accessible through a user-friendly web interface.
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Affiliation(s)
- Aurora Savino
- Molecular Biotechnology Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, 10126 Turin, Italy;
| | - Niccolò De Marzo
- Molecular Biotechnology Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, 10126 Turin, Italy;
| | - Paolo Provero
- Department of Neurosciences “Rita Levi Montalcini”, University of Turin, Corso Massimo D’Azeglio 52, 10126 Turin, Italy;
- Center for Omics Sciences, Ospedale San Raffaele IRCCS, Via Olgettina 60, 20132 Milan, Italy
| | - Valeria Poli
- Molecular Biotechnology Center, Department of Molecular Biotechnology and Health Sciences, University of Turin, Via Nizza 52, 10126 Turin, Italy;
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