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Vadakedath S, Kandi V, Ca J, Vijayan S, Achyut KC, Uppuluri S, Reddy PKK, Ramesh M, Kumar PP. Mitochondrial Deoxyribonucleic Acid (mtDNA), Maternal Inheritance, and Their Role in the Development of Cancers: A Scoping Review. Cureus 2023; 15:e39812. [PMID: 37397663 PMCID: PMC10314188 DOI: 10.7759/cureus.39812] [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] [Accepted: 05/31/2023] [Indexed: 07/04/2023] Open
Abstract
Mitochondrial DNA (mtDNA) is a small, circular, double-stranded DNA inherited from the mother during fertilization. Evolutionary evidence supported by the endosymbiotic theory identifies mitochondria as an organelle that could have descended from prokaryotes. This may be the reason for the independent function and inheritance pattern shown by mtDNA. The unstable nature of mtDNA due to the lack of protective histones, and effective repair systems make it more vulnerable to mutations. The mtDNA and its mutations could be maternally inherited thereby predisposing the offspring to various cancers like breast and ovarian cancers among others. Although mitochondria are considered heteroplasmic wherein variations among the multiple mtDNA genomes are noticed, mothers can have mitochondrial populations that are homoplasmic for a given mitochondrial mutation. Homoplasmic mitochondrial mutations may be transmitted to all maternal offspring. However, due to the complex interplay between the mitochondrial and nuclear genomes, it is often difficult to predict disease outcomes, even with homoplasmic mitochondrial populations. Heteroplasmic mtDNA mutations can be maternally inherited, but the proportion of mutated alleles differs markedly between offspring within one generation. This led to the genetic bottleneck hypothesis, explaining the rapid changes in allele frequency witnessed during the transmission of mtDNA from one generation to the next. Although a physical reduction in mtDNA has been demonstrated in several species, a comprehensive understanding of the molecular mechanisms is yet to be demonstrated. Despite initially thought to be limited to the germline, there is evidence that blockages exist in different cell types during development, perhaps explaining why different tissues in the same organism contain different levels of mutated mtDNA. In this review, we comprehensively discuss the potential mechanisms through which mtDNA undergoes mutations and the maternal mode of transmission that contributes to the development of tumors, especially breast and ovarian cancers.
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Affiliation(s)
| | - Venkataramana Kandi
- Clinical Microbiology, Prathima Institute of Medical Sciences, Karimnagar, IND
| | - Jayashankar Ca
- Internal Medicine, Vydehi Institute of Medical Sciences and Research Centre, Bengaluru, IND
| | - Swapna Vijayan
- Pediatrics, Sir CV Raman General Hospital, Bengaluru, IND
| | - Kushal C Achyut
- Internal Medicine, Vydehi Institute of Medical Sciences and Research Centre, Bangalore, IND
| | - Shivani Uppuluri
- Internal Medicine, Vydehi Institute of Medical Sciences and Research Centre, Bengaluru, IND
| | - Praveen Kumar K Reddy
- General Medicine, Vydehi Institute of Medical Sciences and Research Centre, Bengaluru, IND
| | - Monish Ramesh
- Internal Medicine, Vydehi Institute of Medical Sciences and Research Centre, Bengaluru, IND
| | - P Pavan Kumar
- General Medicine, Vydehi Institute of Medical Sciences and Research Centre, Bengaluru, IND
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Czegle I, Huang C, Soria PG, Purkiss DW, Shields A, Wappler-Guzzetta EA. The Role of Genetic Mutations in Mitochondrial-Driven Cancer Growth in Selected Tumors: Breast and Gynecological Malignancies. Life (Basel) 2023; 13:life13040996. [PMID: 37109525 PMCID: PMC10145875 DOI: 10.3390/life13040996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2022] [Revised: 03/15/2023] [Accepted: 03/31/2023] [Indexed: 04/29/2023] Open
Abstract
There is an increasing understanding of the molecular and cytogenetic background of various tumors that helps us better conceptualize the pathogenesis of specific diseases. Additionally, in many cases, these molecular and cytogenetic alterations have diagnostic, prognostic, and/or therapeutic applications that are heavily used in clinical practice. Given that there is always room for improvement in cancer treatments and in cancer patient management, it is important to discover new therapeutic targets for affected individuals. In this review, we discuss mitochondrial changes in breast and gynecological (endometrial and ovarian) cancers. In addition, we review how the frequently altered genes in these diseases (BRCA1/2, HER2, PTEN, PIK3CA, CTNNB1, RAS, CTNNB1, FGFR, TP53, ARID1A, and TERT) affect the mitochondria, highlighting the possible associated individual therapeutic targets. With this approach, drugs targeting mitochondrial glucose or fatty acid metabolism, reactive oxygen species production, mitochondrial biogenesis, mtDNA transcription, mitophagy, or cell death pathways could provide further tailored treatment.
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Affiliation(s)
- Ibolya Czegle
- Department of Internal Medicine and Haematology, Semmelweis University, H-1085 Budapest, Hungary
| | - Chelsea Huang
- Department of Pathology and Laboratory Medicine, Loma Linda University Health, Loma Linda, CA 92354, USA
| | - Priscilla Geraldine Soria
- Department of Pathology and Laboratory Medicine, Loma Linda University Health, Loma Linda, CA 92354, USA
| | - Dylan Wesley Purkiss
- Department of Pathology and Laboratory Medicine, Loma Linda University Health, Loma Linda, CA 92354, USA
| | - Andrea Shields
- Department of Pathology and Laboratory Medicine, Loma Linda University Health, Loma Linda, CA 92354, USA
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Ji X, Guo W, Gu X, Guo S, Zhou K, Su L, Yuan Q, Liu Y, Guo X, Huang Q, Xing J. Mutational profiling of mtDNA control region reveals tumor-specific evolutionary selection involved in mitochondrial dysfunction. EBioMedicine 2022; 80:104058. [PMID: 35594659 PMCID: PMC9121266 DOI: 10.1016/j.ebiom.2022.104058] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2021] [Revised: 04/06/2022] [Accepted: 04/28/2022] [Indexed: 11/05/2022] Open
Abstract
Background Mitochondrial DNA (mtDNA) mutations alter mitochondrial function in oxidative metabolism and play an important role in tumorigenesis. A series of studies have demonstrated that the mtDNA control region (mtCTR), which is essential for mtDNA replication and transcription, represents a mutational hotspot in human tumors. However, a comprehensive pan-cancer evolutionary pattern analysis of mtCTR mutations is urgently needed. Methods We generated a comprehensive combined dataset containing 10026 mtDNA somatic mutations from 4664 patients, covering 20 tumor types based on public and private next-generation sequencing data. Findings Our results demonstrated a significantly higher and much more variable mutation rate in mtCTR than in the coding region across different tumor types. Moreover, our data showed a remarkable distributional bias of tumor somatic mutations between the hypervariable segment (HVS) and non-HVS, with a significantly higher mutation density and average mutation sites in HVS. Importantly, the tumor-specific mutational pattern between mtCTR HVS and non-HVS was identified, which was classified into three evolutionary selection types (relaxed, moderate, and strict constraint types). Analysis of substitution patterns revealed that the prevalence of CH > TH in non-HVS greatly contributed to the mutational selection pattern of mtCTR across different tumor types. Furthermore, we found that the mutational pattern of mtCTR in the four tumor types was clearly associated with mitochondrial biogenesis, mitochondrial oxidative metabolism, and the overall survival of patients. Interpretation Our results suggest that somatic mutations in mtCTR may be shaped by tumor-specific selective pressure and are involved in tumorigenesis. Fundings National Natural Science Foundation of China [grants 82020108023, 81830070, 81872302], and Autonomous Project of State Key Laboratory of Cancer Biology, China [grants CBSKL2019ZZ06, CBSKL2019ZZ27].
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Li H, Cheng W, Chen B, Pu S, Fan N, Zhang X, Jiao D, Shi D, Guo J, Li Z, Qing Y, Jia B, Zhao HY, Wei HJ. Efficient Generation of P53 Biallelic Mutations in Diannan Miniature Pigs Using RNA-Guided Base Editing. Life (Basel) 2021; 11:life11121417. [PMID: 34947951 PMCID: PMC8706133 DOI: 10.3390/life11121417] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2021] [Revised: 12/09/2021] [Accepted: 12/10/2021] [Indexed: 12/30/2022] Open
Abstract
The base editing 3 (BE3) system, a single-base gene editing technology developed using CRISPR/Cas9n, has a broad range of applications for human disease model construction and gene therapy, as it is highly efficient, accurate, and non-destructive. P53 mutations are present in more than 50% of human malignancies. Due to the similarities between humans and pigs at the molecular level, pig models carrying P53 mutations can be used to research the mechanism of tumorigenesis and improve tumor diagnosis and treatment. According to pathogenic mutations of the human P53 gene at W146* and Q100*, sgRNAs were designed to target exon 4 and exon 5 of the porcine P53 gene. The target editing efficiencies of the two sgRNAs were 61.9% and 50.0%, respectively. The editing efficiency of the BE3 system was highest (about 60%) when C (or G) was at the 5th base. Puromycin screening revealed that 75.0% (21/28) and 68.7% (22/32) of cell colonies contained a P53 mutation at sgRNA-Exon5 and sgRNA-Exon4, respectively. The reconstructed embryos from sgRNA-Exon5-5# were transferred into six recipient gilts, all of which aborted. The reconstructed embryos from sgRNA-Exon4-7# were transferred into 6 recipient gilts, 3 of which became pregnant, resulting in 14 live and 3 dead piglets. Sequencing analyses of the target site confirmed 1 P53 monoallelic mutation and 16 biallelic mutations. The qPCR analysis showed that the P53 mRNA expression level was significantly decreased in different tissues of the P53 mutant piglets (p < 0.05). Additionally, confocal microscopy and western blot analysis revealed an absence of P53 expression in the P53 mutant fibroblasts, livers, and lung tissues. In conclusion, a porcine cancer model with a P53 point mutation can be obtained via the BE3 system and somatic cell nuclear transfer (SCNT).
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Affiliation(s)
- Honghui Li
- Yunnan Key Laboratory of Porcine Gene Editing and Xenotransplantation, Kunming 650201, China; (H.L.); (W.C.); (B.C.); (S.P.); (N.F.); (X.Z.); (D.J.); (D.S.); (J.G.); (Z.L.); (Y.Q.); (B.J.)
- Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, China
| | - Wenmin Cheng
- Yunnan Key Laboratory of Porcine Gene Editing and Xenotransplantation, Kunming 650201, China; (H.L.); (W.C.); (B.C.); (S.P.); (N.F.); (X.Z.); (D.J.); (D.S.); (J.G.); (Z.L.); (Y.Q.); (B.J.)
- Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, China
| | - Bowei Chen
- Yunnan Key Laboratory of Porcine Gene Editing and Xenotransplantation, Kunming 650201, China; (H.L.); (W.C.); (B.C.); (S.P.); (N.F.); (X.Z.); (D.J.); (D.S.); (J.G.); (Z.L.); (Y.Q.); (B.J.)
- College of Veterinary Medicine, Yunnan Agricultural University, Kunming 650201, China
| | - Shaoxia Pu
- Yunnan Key Laboratory of Porcine Gene Editing and Xenotransplantation, Kunming 650201, China; (H.L.); (W.C.); (B.C.); (S.P.); (N.F.); (X.Z.); (D.J.); (D.S.); (J.G.); (Z.L.); (Y.Q.); (B.J.)
- College of Veterinary Medicine, Yunnan Agricultural University, Kunming 650201, China
| | - Ninglin Fan
- Yunnan Key Laboratory of Porcine Gene Editing and Xenotransplantation, Kunming 650201, China; (H.L.); (W.C.); (B.C.); (S.P.); (N.F.); (X.Z.); (D.J.); (D.S.); (J.G.); (Z.L.); (Y.Q.); (B.J.)
- Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, China
| | - Xiaolin Zhang
- Yunnan Key Laboratory of Porcine Gene Editing and Xenotransplantation, Kunming 650201, China; (H.L.); (W.C.); (B.C.); (S.P.); (N.F.); (X.Z.); (D.J.); (D.S.); (J.G.); (Z.L.); (Y.Q.); (B.J.)
- Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, China
| | - Deling Jiao
- Yunnan Key Laboratory of Porcine Gene Editing and Xenotransplantation, Kunming 650201, China; (H.L.); (W.C.); (B.C.); (S.P.); (N.F.); (X.Z.); (D.J.); (D.S.); (J.G.); (Z.L.); (Y.Q.); (B.J.)
- Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, China
| | - Dejia Shi
- Yunnan Key Laboratory of Porcine Gene Editing and Xenotransplantation, Kunming 650201, China; (H.L.); (W.C.); (B.C.); (S.P.); (N.F.); (X.Z.); (D.J.); (D.S.); (J.G.); (Z.L.); (Y.Q.); (B.J.)
- Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, China
| | - Jianxiong Guo
- Yunnan Key Laboratory of Porcine Gene Editing and Xenotransplantation, Kunming 650201, China; (H.L.); (W.C.); (B.C.); (S.P.); (N.F.); (X.Z.); (D.J.); (D.S.); (J.G.); (Z.L.); (Y.Q.); (B.J.)
| | - Zhuo Li
- Yunnan Key Laboratory of Porcine Gene Editing and Xenotransplantation, Kunming 650201, China; (H.L.); (W.C.); (B.C.); (S.P.); (N.F.); (X.Z.); (D.J.); (D.S.); (J.G.); (Z.L.); (Y.Q.); (B.J.)
- Faculty of Animal Science and Technology, Yunnan Agricultural University, Kunming 650201, China
| | - Yubo Qing
- Yunnan Key Laboratory of Porcine Gene Editing and Xenotransplantation, Kunming 650201, China; (H.L.); (W.C.); (B.C.); (S.P.); (N.F.); (X.Z.); (D.J.); (D.S.); (J.G.); (Z.L.); (Y.Q.); (B.J.)
- College of Veterinary Medicine, Yunnan Agricultural University, Kunming 650201, China
| | - Baoyu Jia
- Yunnan Key Laboratory of Porcine Gene Editing and Xenotransplantation, Kunming 650201, China; (H.L.); (W.C.); (B.C.); (S.P.); (N.F.); (X.Z.); (D.J.); (D.S.); (J.G.); (Z.L.); (Y.Q.); (B.J.)
- College of Veterinary Medicine, Yunnan Agricultural University, Kunming 650201, China
| | - Hong-Ye Zhao
- Yunnan Key Laboratory of Porcine Gene Editing and Xenotransplantation, Kunming 650201, China; (H.L.); (W.C.); (B.C.); (S.P.); (N.F.); (X.Z.); (D.J.); (D.S.); (J.G.); (Z.L.); (Y.Q.); (B.J.)
- College of Plant Protection, Yunnan Agricultural University, Kunming 650201, China
- Correspondence: (H.-Y.Z.); (H.-J.W.)
| | - Hong-Jiang Wei
- Yunnan Key Laboratory of Porcine Gene Editing and Xenotransplantation, Kunming 650201, China; (H.L.); (W.C.); (B.C.); (S.P.); (N.F.); (X.Z.); (D.J.); (D.S.); (J.G.); (Z.L.); (Y.Q.); (B.J.)
- College of Veterinary Medicine, Yunnan Agricultural University, Kunming 650201, China
- Correspondence: (H.-Y.Z.); (H.-J.W.)
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Abstract
Mitochondria play various important roles in energy production, metabolism, and apoptosis. Mitochondrial dysfunction caused by alterations in mitochondrial DNA (mtDNA) can lead to the initiation and progression of cancers and other diseases. These alterations include mutations and copy number variations. Especially, the mutations in D-loop, MT-ND1, and MT-ND5 affect mitochondrial functions and are widely detected in various cancers. Meanwhile, several other mutations have been correlated with muscular and neuronal diseases, especially MT-TL1 is deeply related. These pieces of evidence indicated mtDNA alterations in diseases show potential as a novel therapeutic target. mtDNA repair enzymes are the target for delaying or stalling the mtDNA damage-induced cancer progression and metastasis. Moreover, some mutations reveal a prognosis ability of the drug resistance. Current efforts aim to develop mitochondrial transplantation technique as a direct cure for deregulated mitochondria-associated diseases. This review summarizes the implications of mitochondrial dysfunction in cancers and other pathologies; and discusses the relevance of mitochondria-targeted therapies, along with their contribution as potential biomarkers.
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Affiliation(s)
- Ngoc Ngo Yen Nguyen
- Department of Biomedical Science, Graduate School, Kyung Hee University, Seoul, Republic of Korea.,Biomedical Science Institute, Kyung Hee University, Seoul, Republic of Korea
| | - Sung Soo Kim
- Biomedical Science Institute, Kyung Hee University, Seoul, Republic of Korea.,Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul, Republic of Korea
| | - Yong Hwa Jo
- Biomedical Science Institute, Kyung Hee University, Seoul, Republic of Korea.,Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul, Republic of Korea
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Mitochondria as playmakers of apoptosis, autophagy and senescence. Semin Cell Dev Biol 2019; 98:139-153. [PMID: 31154010 DOI: 10.1016/j.semcdb.2019.05.022] [Citation(s) in RCA: 293] [Impact Index Per Article: 58.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2019] [Revised: 05/21/2019] [Accepted: 05/22/2019] [Indexed: 12/16/2022]
Abstract
Mitochondria are the key energy-producing organelles and cellular source of reactive species. They are responsible for managing cell life and death by a balanced homeostasis passing through a network of structures, regulated principally via fission and fusion. Herein we discuss about the most advanced findings considering mitochondria as dynamic biophysical systems playing compelling roles in the regulation of energy metabolism in both physiologic and pathologic processes controlling cell death and survival. Precisely, we focus on the mitochondrial commitment to the onset, maintenance and counteraction of apoptosis, autophagy and senescence in the bioenergetic reprogramming of cancer cells. In this context, looking for a pharmacological manipulation of cell death processes as a successful route for future targeted therapies, there is major biotechnological challenge in underlining the location, function and molecular mechanism of mitochondrial proteins. Based on the critical role of mitochondrial functions for cellular health, a better knowledge of the main molecular players in mitochondria disfunction could be decisive for the therapeutical control of degenerative diseases, including cancer.
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Yusoff AAM, Abdullah WSW, Khair SZNM, Radzak SMA. A comprehensive overview of mitochondrial DNA 4977-bp deletion in cancer studies. Oncol Rev 2019; 13:409. [PMID: 31044027 PMCID: PMC6478002 DOI: 10.4081/oncol.2019.409] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2018] [Accepted: 02/19/2019] [Indexed: 01/04/2023] Open
Abstract
Mitochondria are cellular machines essential for energy production. The biogenesis of mitochondria is a highly complex and it depends on the coordination of the nuclear and mitochondrial genome. Mitochondrial DNA (mtDNA) mutations and deletions are suspected to be associated with carcinogenesis. The most described mtDNA deletion in various human cancers is called the 4977-bp common deletion (mDNA4977) and it has been explored since two decades. In spite of that, its implication in carcinogenesis still unknown and its predictive and prognostic impact remains controversial. This review article provides an overview of some of the cellular and molecular mechanisms underlying mDNA4977 formation and a detailed summary about mDNA4977 reported in various types of cancers. The current knowledges of mDNA4977 as a prognostic and predictive marker are also discussed.
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Affiliation(s)
- Abdul Aziz Mohamed Yusoff
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia, Kelantan, Malaysia
| | - Wan Salihah Wan Abdullah
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia, Kelantan, Malaysia
| | | | - Siti Muslihah Abd Radzak
- Department of Neurosciences, School of Medical Sciences, Universiti Sains Malaysia, Kelantan, Malaysia
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Hertweck KL, Dasgupta S. The Landscape of mtDNA Modifications in Cancer: A Tale of Two Cities. Front Oncol 2017; 7:262. [PMID: 29164061 PMCID: PMC5673620 DOI: 10.3389/fonc.2017.00262] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2017] [Accepted: 10/18/2017] [Indexed: 12/25/2022] Open
Abstract
Mitochondria from normal and cancerous cells represent a tale of two cities, wherein both execute similar processes but with different cellular and molecular effects. Given the number of reviews currently available which describe the functional implications of mitochondrial mutations in cancer, this article focuses on documenting current knowledge in the abundance and distribution of somatic mitochondrial mutations, followed by elucidation of processes which affect the fate of mutations in cancer cells. The conclusion includes an overview of translational implications for mtDNA mutations, as well as recommendations for future research uniting mitochondrial variants and tumorigenesis.
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Affiliation(s)
- Kate L Hertweck
- Department of Biology, The University of Texas at Tyler, Tyler, TX, United States
| | - Santanu Dasgupta
- Department of Cellular and Molecular Biology, The University of Texas Health Science Center at Tyler, Tyler, TX, United States
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Soon BH, Abdul Murad NA, Then SM, Abu Bakar A, Fadzil F, Thanabalan J, Mohd Haspani MS, Toh CJ, Mohd Tamil A, Harun R, Wan Ngah WZ, Jamal R. Mitochondrial DNA Mutations in Grade II and III Glioma Cell Lines Are Associated with Significant Mitochondrial Dysfunction and Higher Oxidative Stress. Front Physiol 2017; 8:231. [PMID: 28484394 PMCID: PMC5399085 DOI: 10.3389/fphys.2017.00231] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 03/31/2017] [Indexed: 01/13/2023] Open
Abstract
The role of mitochondria in tumorigenesis has regained much attention as it could dysregulate cellular energetics, oxidative stress and apoptosis. However, the role of mitochondria in different grade gliomasis still unknown. This study aimed to identify mitochondrial DNA (mtDNA) sequence variations that could possibly affect the mitochondrial functions and also the oxidative stress status. Three different grades of human glioma cell lines and a normal human astrocyte cell line were cultured in-vitro and tested for oxidative stress biomarkers. Relative oxidative stress level, mitochondria activity, and mitochondrial mass were determined by live cell imaging with confocal laser scanning microscope using CM-H2DCFDA, MitoTracker Green, and MitoTracker Orange stains. The entire mitochondrial genome was sequenced using the AffymetrixGeneChip Human Mitochondrial Resequencing Array 2.0. The mitochondrial sequence variations were subjected to phylogenetic haplogroup assessment and pathogenicity of the mutations were predicted using pMUT and PolyPhen2. The Grade II astrocytoma cells showed increased oxidative stress wherea high level of 8-OHdG and oxidative stress indicator were observed. Simultaneously, Grade II and III glioma cells showed relatively poor mitochondria functions and increased number of mutations in the coding region of the mtDNA which could be due to high levels of oxidative stress in these cells. These non-synonymous mtDNA sequence variations were predicted to be pathogenic and could possibly lead to protein dysfunction, leading to oxidative phosphorylation (OXPHOS) impairment, mitochondria dysfunction and could create a vicious cycle of oxidative stress. The Grade IV cells had no missense mutation but preserved intact mitochondria and excellent antioxidant defense mechanisms thus ensuring better survival. In conclusion, Grade II and III glioma cells demonstrated coding region mtDNA mutations, leading to mitochondrial dysfunction and higher oxidative stress.
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Affiliation(s)
- Bee Hong Soon
- UKM Medical Molecular Biology Institute, Universiti Kebangsaan MalaysiaKuala Lumpur, Malaysia.,Division of Neurosurgery, Department of Surgery, Faculty of Medicine, Universiti Kebangsaan MalaysiaKuala Lumpur, Malaysia
| | - Nor Azian Abdul Murad
- UKM Medical Molecular Biology Institute, Universiti Kebangsaan MalaysiaKuala Lumpur, Malaysia
| | - Sue-Mian Then
- UKM Medical Molecular Biology Institute, Universiti Kebangsaan MalaysiaKuala Lumpur, Malaysia.,The University of Nottingham Malaysia CampusSemenyih, Malaysia
| | - Azizi Abu Bakar
- Division of Neurosurgery, Department of Surgery, Faculty of Medicine, Universiti Kebangsaan MalaysiaKuala Lumpur, Malaysia
| | - Farizal Fadzil
- Division of Neurosurgery, Department of Surgery, Faculty of Medicine, Universiti Kebangsaan MalaysiaKuala Lumpur, Malaysia
| | - Jegan Thanabalan
- Division of Neurosurgery, Department of Surgery, Faculty of Medicine, Universiti Kebangsaan MalaysiaKuala Lumpur, Malaysia
| | | | - Charng Jeng Toh
- Division of Neurosurgery, Department of Surgery, Faculty of Medicine, Universiti Kebangsaan MalaysiaKuala Lumpur, Malaysia
| | - Azmi Mohd Tamil
- Department of Community Health, Faculty of Medicine, Universiti Kebangsaan MalaysiaKuala Lumpur, Malaysia
| | - Roslan Harun
- UKM Medical Molecular Biology Institute, Universiti Kebangsaan MalaysiaKuala Lumpur, Malaysia
| | - Wan Z Wan Ngah
- UKM Medical Molecular Biology Institute, Universiti Kebangsaan MalaysiaKuala Lumpur, Malaysia
| | - Rahman Jamal
- UKM Medical Molecular Biology Institute, Universiti Kebangsaan MalaysiaKuala Lumpur, Malaysia
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Koronowicz AA, Banks P, Domagała D, Master A, Leszczyńska T, Piasna E, Marynowska M, Laidler P. Fatty acid extract from CLA-enriched egg yolks can mediate transcriptome reprogramming of MCF-7 cancer cells to prevent their growth and proliferation. GENES AND NUTRITION 2016; 11:22. [PMID: 27551323 PMCID: PMC4968440 DOI: 10.1186/s12263-016-0537-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Accepted: 07/12/2016] [Indexed: 02/06/2023]
Abstract
Background Our previous study showed that fatty acids extract obtained from CLA-enriched egg yolks (EFA-CLA) suppressed the viability of MCF-7 cancer cell line more effectively than extract from non-enriched egg yolks (EFA). In this study, we analysed the effect of EFA-CLA and EFA on transcriptome profile of MCF-7 cells by applying the whole Human Genome Microarray technology. Results We found that EFA-CLA and EFA treated cells differentially regulated genes involved in cancer development and progression. EFA-CLA, compared to EFA, positively increased the mRNA expression of TSC2 and PTEN tumor suppressors as well as decreased the expression of NOTCH1, AGPS, GNA12, STAT3, UCP2, HIGD2A, HIF1A, PPKAR1A oncogenes. Conclusions We show for the first time that EFA-CLA can regulate genes engaged in AKT/mTOR pathway and inhibiting cell cycle progression. The observed results are most likely achieved by the combined effect of both: incorporated CLA isomers and other fatty acids in eggs organically modified through hens’ diet. Our results suggest that CLA-enriched eggs could be easily available food products with a potential of a cancer chemopreventive agent. Electronic supplementary material The online version of this article (doi:10.1186/s12263-016-0537-z) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Aneta A Koronowicz
- Department of Human Nutrition, Faculty of Food Technology, University of Agriculture, Krakow, Poland
| | - Paula Banks
- Department of Human Nutrition, Faculty of Food Technology, University of Agriculture, Krakow, Poland
| | - Dominik Domagała
- Department of Human Nutrition, Faculty of Food Technology, University of Agriculture, Krakow, Poland
| | - Adam Master
- Department of Biochemistry and Molecular Biology, Medical Centre for Postgraduate Education, Warsaw, Poland
| | - Teresa Leszczyńska
- Department of Human Nutrition, Faculty of Food Technology, University of Agriculture, Krakow, Poland
| | - Ewelina Piasna
- Department of Human Nutrition, Faculty of Food Technology, University of Agriculture, Krakow, Poland
| | - Mariola Marynowska
- Department of Human Nutrition, Faculty of Food Technology, University of Agriculture, Krakow, Poland
| | - Piotr Laidler
- Department of Medical Biochemistry, Jagiellonian University Medical College, Krakow, Poland
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Surdyka M, Slaska B. Defect of the mitochondrial DNA hypervariable region as a risk factor for canine mammary tumour. Vet Comp Oncol 2016; 15:820-828. [PMID: 27198058 DOI: 10.1111/vco.12224] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2015] [Revised: 01/05/2016] [Accepted: 02/07/2016] [Indexed: 12/12/2022]
Abstract
The aim of this study was to identify mutations in the hypervariable region of mitochondrial DNA in canine mammary tumours and to determine their association with the process of neoplastic transformation. A total of 93 biological samples, including blood as well as normal and neoplastic tissue samples from 31 dogs with diagnosed malignant canine mammary tumours were analysed. DNA extraction, amplification and sequencing of the D-loop as well as bioinformatic and statistical analyses were performed. In the mitochondrial D-loop sequence, 26 polymorphic loci and 5 mutations were identified. For the first time, D-loop length heteroplasmy was detected in dogs with mammary tumours. The malignancy grade exerted no effect on the presence of nucleotide changes. A statistically significant association between the presence of mutations and polymorphisms and the size of dogs was demonstrated. The 100% frequency of length heteroplasmy may imply that this is a hotspot mutation of canine mammary tumour.
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Affiliation(s)
- M Surdyka
- Department of Biological Bases of Animal Production, University of Life Sciences in Lublin, Lublin, Poland
| | - B Slaska
- Department of Biological Bases of Animal Production, University of Life Sciences in Lublin, Lublin, Poland
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Li S, Wan P, Peng T, Xiao K, Su M, Shang L, Xu B, Su Z, Ye X, Peng N, Qin Q, Li L. Associations between sequence variations in the mitochondrial DNA D-loop region and outcome of hepatocellular carcinoma. Oncol Lett 2016; 11:3723-3728. [PMID: 27313683 DOI: 10.3892/ol.2016.4466] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 02/24/2016] [Indexed: 11/05/2022] Open
Abstract
The association between mitochondrial DNA (mtDNA) polymorphisms or mutations and the prognoses of cancer have been investigated previously, but the results have been ambiguous. In the present study, the associations between sequence variations in the mtDNA D-loop region and the outcomes of patients with hepatocellular carcinoma (HCC) were analysed. A total of 140 patients with HCC (123 males and 17 females), who were hospitalised to undergo radical resection, were studied. Polymerase chain reaction and direct sequencing were performed to detect the sequence variations in the mtDNA D-loop region. Multivariate and univariate analyses were conducted to determine important factors in the prognosis of HCC. A total of 150 point sequence variations were observed in the 140 cases (13 point mutations, 8 insertions, 20 deletions and 116 polymorphisms). The variation rate was 13.4% (150/1, 122). mtDNA nucleotide 150 (C/T) was an independent factor in the logistic regression for early/late recurrence of HCC. Patients with 150T appeared to have later recurrences. In a Cox proportional hazards regression model, hepatitis B virus DNA, Child-Pugh class, differentiation degree, tumour-node-metastasis (TNM) stage, nucleotide 16263 (T/C) and nucleotide 315 (N/insertion C) were independent factors for tumour-free survival time. Patients with the 16263T allele had a greater tumour-free survival time than patients with the 16263C allele. Similarly, patients with 315 insertion C had a superior tumour-free survival time when compared with patients with 315 N (normal). In the Cox proportional hazards regression model, recurrence type (early/late), Child-Pugh class, TNM stage and adjuvant treatment after tumour recurrence (none or one/more than one treatment) were independent factors for overall survival. None of the mtDNA variations served as independent factors. Patients with late recurrence, Child-Pugh class A, and low TNM stages and/or those who received more than one adjuvant treatment following tumour recurrence had favourable outcomes. mtDNA D-loop polymorphisms were associated with early recurrence and tumour-free survival time, but not with overall survival. mtDNA D-loop mutations in HCC were infrequent and lacked prognostic utility. The detection of mtDNA D-loop polymorphisms may assist in identifying risk factors for HCC prognosis, particularly for the short-term outcome, thereby aiding the construction of an appropriate therapeutic strategy.
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Affiliation(s)
- Shilai Li
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Peiqi Wan
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Tao Peng
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Kaiyin Xiao
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Ming Su
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Liming Shang
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Banghao Xu
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Zhixiong Su
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Xinping Ye
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Ning Peng
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Quanlin Qin
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
| | - Lequn Li
- Department of Hepatobiliary Surgery, The First Affiliated Hospital of Guangxi Medical University, Nanning, Guangxi 530021, P.R. China
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Porporato PE, Payen VL, Baselet B, Sonveaux P. Metabolic changes associated with tumor metastasis, part 2: Mitochondria, lipid and amino acid metabolism. Cell Mol Life Sci 2016; 73:1349-63. [PMID: 26646069 PMCID: PMC11108268 DOI: 10.1007/s00018-015-2100-2] [Citation(s) in RCA: 66] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Revised: 11/16/2015] [Accepted: 11/23/2015] [Indexed: 12/13/2022]
Abstract
Metabolic alterations are a hallmark of cancer controlling tumor progression and metastasis. Among the various metabolic phenotypes encountered in tumors, this review focuses on the contributions of mitochondria, lipid and amino acid metabolism to the metastatic process. Tumor cells require functional mitochondria to grow, proliferate and metastasize, but shifts in mitochondrial activities confer pro-metastatic traits encompassing increased production of mitochondrial reactive oxygen species (mtROS), enhanced resistance to apoptosis and the increased or de novo production of metabolic intermediates of the TCA cycle behaving as oncometabolites, including succinate, fumarate, and D-2-hydroxyglutarate that control energy production, biosynthesis and the redox state. Lipid metabolism and the metabolism of amino acids, such as glutamine, glutamate and proline are also currently emerging as focal control points of cancer metastasis.
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Affiliation(s)
- Paolo E Porporato
- Pole of Pharmacology, Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain (UCL), Avenue Emmanuel Mounier 52, box B1.53.09, 1200, Brussels, Belgium
| | - Valéry L Payen
- Pole of Pharmacology, Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain (UCL), Avenue Emmanuel Mounier 52, box B1.53.09, 1200, Brussels, Belgium
| | - Bjorn Baselet
- Pole of Pharmacology, Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain (UCL), Avenue Emmanuel Mounier 52, box B1.53.09, 1200, Brussels, Belgium
- Radiobiology Unit, Belgian Nuclear Research Centre, SCK·CEN, 2400 Mol, Belgium
| | - Pierre Sonveaux
- Pole of Pharmacology, Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain (UCL), Avenue Emmanuel Mounier 52, box B1.53.09, 1200, Brussels, Belgium.
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Chen L, Duvvuri B, Grigull J, Jamnik R, Wither JE, Wu GE. Experimental evidence that mutated-self peptides derived from mitochondrial DNA somatic mutations have the potential to trigger autoimmunity. Hum Immunol 2014; 75:873-9. [PMID: 24979674 DOI: 10.1016/j.humimm.2014.06.012] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2014] [Revised: 06/19/2014] [Accepted: 06/19/2014] [Indexed: 12/20/2022]
Abstract
Autoimmune disease is a critical health concern, whose etiology remains enigmatic. We hypothesized that immune responses to somatically mutated self proteins could have a role in the development of autoimmune disease. IFN-γ secretion by T cells stimulated with mitochondrial peptides encoded by published mitochondrial DNA was monitored to test the hypothesis. Human peripheral blood mononuclear cells (PBMCs) of healthy controls and autoimmune patients were assessed for their responses to the self peptides and mutated-self peptides differing from self by one amino acid. None of the self peptides but some of the mutated-self peptides elicited an immune response in healthy controls. In some autoimmune patients, PBMCs responded not only to some of the mutated-self peptides, but also to some of the self peptides, suggesting that there is a breach of self-tolerance in these patients. Although PBMCs from healthy controls failed to respond to self peptides when stimulated with self, the mutated-self peptide could elicit a response to the self peptide upon re-stimulation in vitro, suggesting that priming with mutated-self peptides elicits a cross-reactive response with self. The data raise the possibility that DNA somatic mutations are one of the events that trigger and/or sustain T cell responses in autoimmune diseases.
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Affiliation(s)
- Lina Chen
- Department of Kinesiology and Health Science, York University, Canada.
| | - Bhargavi Duvvuri
- Department of Kinesiology and Health Science, York University, Canada
| | - Jörg Grigull
- Department of Mathematics and Statistics, York University, Canada
| | - Roni Jamnik
- Department of Kinesiology and Health Science, York University, Canada
| | - Joan E Wither
- University Health Network and University of Toronto, Canada
| | - Gillian E Wu
- Department of Kinesiology and Health Science, York University, Canada
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Ganepola GAP, Nizin J, Rutledge JR, Chang DH. Use of blood-based biomarkers for early diagnosis and surveillance of colorectal cancer. World J Gastrointest Oncol 2014; 6:83-97. [PMID: 24734154 PMCID: PMC3981973 DOI: 10.4251/wjgo.v6.i4.83] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 03/08/2014] [Accepted: 03/17/2014] [Indexed: 02/05/2023] Open
Abstract
Early screening for colorectal cancer (CRC) holds the key to combat and control the increasing global burden of CRC morbidity and mortality. However, the current available screening modalities are severely inadequate because of their high cost and cumbersome preparatory procedures that ultimately lead to a low participation rate. People simply do not like to have colonoscopies. It would be ideal, therefore, to develop an alternative modality based on blood biomarkers as the first line screening test. This will allow for the differentiation of the general population from high risk individuals. Colonoscopy would then become the secondary test, to further screen the high risk segment of the population. This will encourage participation and therefore help to reach the goal of early detection and thereby reduce the anticipated increasing global CRC incidence rate. A blood-based screening test is an appealing alternative as it is non-invasive and poses minimal risk to patients. It is easy to perform, can be repeated at shorter intervals, and therefore would likely lead to a much higher participation rate. This review surveys various blood-based test strategies currently under investigation, discusses the potency of what is available, and assesses how new technology may contribute to future test design.
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Mitochondrial DNA mutations and breast tumorigenesis. Biochim Biophys Acta Rev Cancer 2013; 1836:336-44. [PMID: 24140413 DOI: 10.1016/j.bbcan.2013.10.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2013] [Revised: 10/02/2013] [Accepted: 10/05/2013] [Indexed: 12/15/2022]
Abstract
Breast cancer is a heterogeneous disease and genetic factors play an important role in its genesis. Although mutations in tumor suppressors and oncogenes encoded by the nuclear genome are known to play a critical role in breast tumorigenesis, the contribution of the mitochondrial genome to this process is unclear. Like the nuclear genome, the mitochondrial genome also encodes proteins critical for mitochondrion functions such as oxidative phosphorylation (OXPHOS), which is known to be defective in cancer including breast cancer. Mitochondrial DNA (mtDNA) is more susceptible to mutations due to limited repair mechanisms compared to nuclear DNA (nDNA). Thus changes in mitochondrial genes could also contribute to the development of breast cancer. In this review we discuss mtDNA mutations that affect OXPHOS. Continuous acquisition of mtDNA mutations and selection of advantageous mutations ultimately leads to generation of cells that propagate uncontrollably to form tumors. Since irreversible damage to OXPHOS leads to a shift in energy metabolism towards enhanced aerobic glycolysis in most cancers, mutations in mtDNA represent an early event during breast tumorigenesis, and thus may serve as potential biomarkers for early detection and prognosis of breast cancer. Because mtDNA mutations lead to defective OXPHOS, development of agents that target OXPHOS will provide specificity for preventative and therapeutic agents against breast cancer with minimal toxicity.
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Uzawa K, Baba T, Uchida F, Yamatoji M, Kasamatsu A, Sakamoto Y, Ogawara K, Shiiba M, Bukawa H, Tanzawa H. Circulating tumor-derived mutant mitochondrial DNA: a predictive biomarker of clinical prognosis in human squamous cell carcinoma. Oncotarget 2013; 3:670-7. [PMID: 22832574 PMCID: PMC3443250 DOI: 10.18632/oncotarget.523] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
While circulating tumor-derived molecules have been identified in a variety of malignant tumors, it is sometimes difficult to detect the molecular targets due to the lower serum concentration. We report that evaluation of circulating tumor-derived mitochondrial DNA (mtDNA) seems to have novel efficiency for detecting tumoral micrometastasis. In murine xenografting human oral cancer cells, human mtDNAs could be quantitatively detected from multiple organs and blood samples whereas human nucleic DNAs could not. We also determined if this mtDNA blood test was relevant for patients with oral cancer with no histologic evidence of tumoral cells in their surgical margins. For this, mtDNA from normal and tumorous tissues and serum mtDNA obtained pre and postoperatively was examined at three different regions including the displacement loop, 12S-rRNA, and 16S-rRNA. All recurring patients had significantly higher amounts of mutant mtDNAs in the tumoral tissues compared with the non-recurring group. More importantly, on the blood test with the cut-off point by receiver operating characteristic (ROC) curve analysis, while the vast majority of serum mtDNA samples obtained postoperatively in the recurring cases maintained significantly higher amounts of mutant mtDNAs, the non-recurring cases did not, and they showed good prognosis. This is the first report of this approach for managing patients after resection of oral tumors, and may have substantial diagnostic potential for other tumoral types.
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Affiliation(s)
- Katsuhiro Uzawa
- Department of Clinical Molecular Biology, Graduate School of Medicine, Chiba University, Chiba, Japan.
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Santos GCD, Góes ACDS, Vitto HD, Moreira CC, Avvad E, Rumjanek FD, Moura Gallo CVD. Genomic instability at the 13q31 locus and somatic mtDNA mutation in the D-loop site correlate with tumor aggressiveness in sporadic Brazilian breast cancer cases. Clinics (Sao Paulo) 2012; 67:1181-90. [PMID: 23070345 PMCID: PMC3460021 DOI: 10.6061/clinics/2012(10)10] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Accepted: 06/19/2012] [Indexed: 01/09/2023] Open
Abstract
OBJECTIVE Genomic instability is a hallmark of malignant tissues. In this work, we aimed to characterize nuclear and mitochondrial instabilities by determining short tandem repeats and somatic mitochondrial mutations, respectively, in a cohort of Brazilian sporadic breast cancer cases. Furthermore, we performed an association analysis of the molecular findings and the clinical pathological data. METHODS We analyzed 64 matched pairs of breast cancer and adjacent non-cancerous breast samples by genotyping 13 nuclear short tandem repeat loci (namely, D2S123, TPOX, D3S1358, D3S1611, FGA, D7S820, TH01, D13S317, D13S790, D16S539, D17S796, intron 12 BRCA1 and intron 1 TP53) that were amplified with the fluorescent AmpFlSTR Identifiler Genotyping system (Applied Biosystems, USA) and by silver nitrate staining following 6% denaturing polyacrylamide gel electrophoresis. Somatic mtDNA mutations in the D-loop site were assessed with direct sequencing of the hypervariable HVI and HVII mitochondrial regions. RESULTS Half of the cancer tissues presented some nuclear instability. Interestingly, the D13S790 locus was the most frequently affected (36%), while the D2S123 locus presented no alterations. Forty-two percent of the cases showed somatic mitochondrial mutations, the majority at region 303-315 poly-C. We identified associations between Elston grade III, instabilities at 13q31 region (p = 0.0264) and mtDNA mutations (p = 0.0041). Furthermore, instabilities at 13q31 region were also associated with TP53 mutations in the invasive ductal carcinoma cases (p= 0.0207). CONCLUSION Instabilities at 13q31 region and the presence of somatic mtDNA mutations in a D-loop site correlated with tumor aggressiveness.
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Affiliation(s)
- Gilson Costa dos Santos
- Departamento de Genética, Instituto de Biologia Roberto Alcantara Gomes, Universidade do Estado do Rio de Janeiro, Rio de Janeiro/RJ, Brazil
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