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Nanes BA, Bhatt K, Azarova E, Rajendran D, Munawar S, Isogai T, Dean KM, Danuser G. Shifts in keratin isoform expression activate motility signals during wound healing. Dev Cell 2024:S1534-5807(24)00389-7. [PMID: 39002537 DOI: 10.1016/j.devcel.2024.06.011] [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: 06/09/2023] [Revised: 04/15/2024] [Accepted: 06/17/2024] [Indexed: 07/15/2024]
Abstract
Keratin intermediate filaments confer structural stability to epithelial tissues, but the reason this simple mechanical function requires a protein family with 54 isoforms is not understood. During skin wound healing, a shift in keratin isoform expression alters the composition of keratin filaments. If and how this change modulates cellular functions that support epidermal remodeling remains unclear. We report an unexpected effect of keratin isoform variation on kinase signal transduction. Increased expression of wound-associated keratin 6A, but not of steady-state keratin 5, potentiated keratinocyte migration and wound closure without compromising mechanical stability by activating myosin motors to increase contractile force generation. These results substantially expand the functional repertoire of intermediate filaments from their canonical role as mechanical scaffolds to include roles as isoform-tuned signaling scaffolds that organize signal transduction cascades in space and time to influence epithelial cell state.
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Affiliation(s)
- Benjamin A Nanes
- Department of Dermatology, UT Southwestern Medical Center, Dallas, TX 75390, USA; Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center, Dallas, TX 75390, USA.
| | - Kushal Bhatt
- Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Evgenia Azarova
- Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Divya Rajendran
- Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Sabahat Munawar
- Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Tadamoto Isogai
- Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Kevin M Dean
- Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center, Dallas, TX 75390, USA
| | - Gaudenz Danuser
- Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center, Dallas, TX 75390, USA.
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Ge WW, Chen ZM, Chou MW, Ismail F, Chen G, Wu LM, Yang JQ. Mutation p.Arg127Pro in the 1A Domain of KRT16 Causes Pachyonychia Congenita in Chinese Patient: A Case Report of PC Associated with Acral Melanoma. Clin Cosmet Investig Dermatol 2024; 17:1111-1116. [PMID: 38770089 PMCID: PMC11104379 DOI: 10.2147/ccid.s462273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Accepted: 05/04/2024] [Indexed: 05/22/2024]
Abstract
Pachyonychia congenita (PC) is a group of rare hereditary disorders, characterised by hypertrophic nails and palmoplantar keratoderma (PPK), particularly localised to the pressure areas of the feet. At a molecular level, it is caused by mutations in genes encoding KRT6A, KRT6B, KRT6C, KRT16, or KRT17. To identify the underlying gene mutation in a Chinese family with PC presenting with disabling palmoplantar keratoderma and subsequent associated acral melanoma. Genomic DNA was extracted from peripheral blood samples of three available individuals in the Chinese family, which included the patient and his two unaffected sisters. The index patient presented with severe palmoplantar keratoderma as well as a newly diagnosed acral malignant melanoma (MM). Whole-exome sequencing (WES) was carried out with amplification of exon 1 of KRT16 by polymerase chain reaction (PCR). PCR products were then sequenced to identify potential mutations. We identified the proline substitution mutation p.Arg127Pro (c.380G>C) in our patient's 1A domain of KRT16. The same mutation was not found in his sisters or unrelated healthy controls. The mutation (p.Arg127Pro (c.380G>C)) in KRT16 has been reported in Dutch patients with PC. However, it is the first such report of a patient with a PC of Chinese origin. In addition, the acral MM occurred under the background of genetic PPK caused by KRT16 mutation in this patient.
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Affiliation(s)
- Wei-Wei Ge
- Department of Dermatology, Taizhou Second People’s Hospital (Mental Health Center Affiliated to Taizhou University School of Medicine), Taizhou University, Taizhou, Zhejiang, 318000, People’s Republic of China
| | - Zai-Ming Chen
- Department of Dermatology, Taizhou Second People’s Hospital (Mental Health Center Affiliated to Taizhou University School of Medicine), Taizhou University, Taizhou, Zhejiang, 318000, People’s Republic of China
| | - Meng-Wei Chou
- Department of Dermatology, The First Affiliated Hospital of Huzhou University, Huzhou, Zhejiang, People’s Republic of China
| | - Ferina Ismail
- Department of Dermatology, Royal Free Hospital, London, England
| | - Guang Chen
- Department of Dermatology, Taizhou Second People’s Hospital (Mental Health Center Affiliated to Taizhou University School of Medicine), Taizhou University, Taizhou, Zhejiang, 318000, People’s Republic of China
| | - Li-Ming Wu
- Department of Dermatology, the First Hangzhou People’s Hospital, Hangzhou, Zhejiang, People’s Republic of China
| | - Jian-Qiang Yang
- Department of Dermatology, The First Affiliated Hospital of Huzhou University, Huzhou, Zhejiang, People’s Republic of China
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Nanes BA, Bhatt K, Boujemaa-Paterski R, Azarova E, Munawar S, Rajendran D, Isogai T, Dean KM, Medalia O, Danuser G. Keratin isoform shifts modulate motility signals during wound healing. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2023.05.04.538989. [PMID: 37205459 PMCID: PMC10187270 DOI: 10.1101/2023.05.04.538989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Keratin intermediate filaments form strong mechanical scaffolds that confer structural stability to epithelial tissues, but the reason this function requires a protein family with 54 isoforms is not understood. During skin wound healing, a shift in keratin isoform expression alters the composition of keratin filaments. How this change modulates cellular function to support epidermal remodeling remains unclear. We report an unexpected effect of keratin isoform variation on kinase signal transduction. Increased expression of wound-associated keratin 6A, but not of steady-state keratin 5, potentiated keratinocyte migration and wound closure without compromising epidermal stability by activating myosin motors. This pathway depended on isoform-specific interaction between intrinsically disordered keratin head domains and non-filamentous vimentin shuttling myosin-activating kinases. These results substantially expand the functional repertoire of intermediate filaments from their canonical role as mechanical scaffolds to include roles as isoform-tuned signaling scaffolds that organize signal transduction cascades in space and time to influence epithelial cell state.
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Affiliation(s)
- Benjamin A Nanes
- Department of Dermatology, UT Southwestern Medical Center; Dallas, TX 75390, USA
- Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center; Dallas, TX 75390, USA
| | - Kushal Bhatt
- Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center; Dallas, TX 75390, USA
| | | | - Evgenia Azarova
- Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center; Dallas, TX 75390, USA
- Present address: Department of Materials Science and Engineering, Johns Hopkins University; Baltimore, MD 21218, USA
| | - Sabahat Munawar
- Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center; Dallas, TX 75390, USA
| | - Divya Rajendran
- Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center; Dallas, TX 75390, USA
| | - Tadamoto Isogai
- Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center; Dallas, TX 75390, USA
| | - Kevin M Dean
- Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center; Dallas, TX 75390, USA
| | - Ohad Medalia
- Department of Biochemistry, University of Zurich; Zurich CH-8057, Switzerland
| | - Gaudenz Danuser
- Lyda Hill Department of Bioinformatics and Cecil H and Ida Green Center for Systems Biology, UT Southwestern Medical Center; Dallas, TX 75390, USA
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4
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Liang J, Li R, Liu C, Cai Y, Liu Y, Chen P, Zeng K, Li C. A novel heterozygous frameshift mutation in the KRT6A gene responsible for an uncommon phenotype of pachyonychia congenita: One case report and review of literature. Heliyon 2024; 10:e27195. [PMID: 38468954 PMCID: PMC10926126 DOI: 10.1016/j.heliyon.2024.e27195] [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: 01/14/2023] [Revised: 02/21/2024] [Accepted: 02/26/2024] [Indexed: 03/13/2024] Open
Abstract
Pachyonychia congenita is an uncommon autosomal dominant skin disorder characterized by hypertrophic nail dystrophy, palmoplantar keratoderma, oral leukokeratosis, and cutaneous cysts. And fissured tongue is rarely reported in patients with pachyonychia congenita. The disease is primarily associated with mutations in five keratin genes, namely KRT6A, KRT6B, KRT6C, KRT16 or KRT17. Herein we report a 9-year-old Chinese girl who has thickened nails, keratinized plaques, and fissured tongue since birth. To investigate the underlying genetic cause, whole-exome sequencing and Sanger sequencing were performed in this patient and her family members. We identified a candidate variant c.1460-2_1460del (p.S487Lfs*21) in the KRT6A gene (NM_005554.4) by whole-exome sequencing. Sanger sequencing revealed the absence of the mutation in both parents, indicating that it is a de novo variant. Thus, the novel heterozygous frameshift mutation c.1460-2_1460del (p.S487Lfs*21) within exon 9 of KRT6A was identified as the genetic cause of the patient. Our study identified a rare de novo heterozygous frameshift mutation in the KRT6A gene in a patient with pachyonychia congenita presenting fissured tongue. Our findings expand the KRT6A gene mutation spectrum of Pachyonychia congenita, and will contribute to the future genetic counseling and gene therapy for this disease.
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Affiliation(s)
- Jiali Liang
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, 510515, China
| | - Ronghua Li
- Department of Dermatology, Quanzhou First Hospital Affiliated to Fujian Medical University, Quanzhou, 362002, China
| | - Chenmei Liu
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, 510515, China
| | - Yan Cai
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, 510515, China
| | - Yifei Liu
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, 510515, China
| | - Pingjiao Chen
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, 510515, China
| | - Kang Zeng
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, 510515, China
| | - Changxing Li
- Department of Dermatology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, 510515, China
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5
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Tan Y, Ma DL. Pachyonychia Congenita. Indian J Pediatr 2024; 91:300-301. [PMID: 37289311 DOI: 10.1007/s12098-023-04567-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/22/2022] [Accepted: 03/14/2023] [Indexed: 06/09/2023]
Affiliation(s)
- Yan Tan
- Department of Dermatology, Peking Union Medical College Hospital, State Key Laboratory of Complex Severe and Rare Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, National Clinical Research Center for Skin and Immune Diseases, No.1, Shuaifuyuan, Dongcheng District, Beijing, 100730, PR China
| | - Dong-Lai Ma
- Department of Dermatology, Peking Union Medical College Hospital, State Key Laboratory of Complex Severe and Rare Diseases, Chinese Academy of Medical Sciences and Peking Union Medical College, National Clinical Research Center for Skin and Immune Diseases, No.1, Shuaifuyuan, Dongcheng District, Beijing, 100730, PR China.
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Li P, Rietscher K, Jopp H, Magin TM, Omary MB. Posttranslational modifications of keratins and their associated proteins as therapeutic targets in keratin diseases. Curr Opin Cell Biol 2023; 85:102264. [PMID: 37925932 DOI: 10.1016/j.ceb.2023.102264] [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: 06/18/2023] [Revised: 09/04/2023] [Accepted: 09/24/2023] [Indexed: 11/07/2023]
Abstract
The keratin cytoskeleton protects epithelia against mechanical, nonmechanical, and physical stresses, and participates in multiple signaling pathways that regulate cell integrity and resilience. Keratin gene mutations cause multiple rare monoallelic epithelial diseases termed keratinopathies, including the skin diseases Epidermolysis Bullosa Simplex (EBS) and Pachyonychia Congenita (PC), with limited available therapies. The disease-related keratin mutations trigger posttranslational modifications (PTMs) in keratins and their associated proteins that can aggravate the disease. Recent findings of drug high-throughput screening have led to the identification of compounds that may be repurposed, since they are used for other human diseases, to treat keratinopathies. These drugs target unique PTM pathways and sites, including phosphorylation and acetylation of keratins and their associated proteins, and have shed insights into keratin regulation and interactions. They also offer the prospect of testing the use of drug mixtures, with the long view of possible beneficial human use coupled with increased efficacy and lower side effects.
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Affiliation(s)
- Pei Li
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ, USA
| | - Katrin Rietscher
- Division of Cell and Developmental Biology, Institute of Biology, Leipzig University, Leipzig, Germany
| | - Henriette Jopp
- Division of Cell and Developmental Biology, Institute of Biology, Leipzig University, Leipzig, Germany
| | - Thomas M Magin
- Division of Cell and Developmental Biology, Institute of Biology, Leipzig University, Leipzig, Germany.
| | - M Bishr Omary
- Center for Advanced Biotechnology and Medicine, Rutgers University, Piscataway, NJ, USA.
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A Kaleidoscope of Keratin Gene Expression and the Mosaic of Its Regulatory Mechanisms. Int J Mol Sci 2023; 24:ijms24065603. [PMID: 36982676 PMCID: PMC10052683 DOI: 10.3390/ijms24065603] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/07/2023] [Accepted: 03/10/2023] [Indexed: 03/17/2023] Open
Abstract
Keratins are a family of intermediate filament-forming proteins highly specific to epithelial cells. A combination of expressed keratin genes is a defining property of the epithelium belonging to a certain type, organ/tissue, cell differentiation potential, and at normal or pathological conditions. In a variety of processes such as differentiation and maturation, as well as during acute or chronic injury and malignant transformation, keratin expression undergoes switching: an initial keratin profile changes accordingly to changed cell functions and location within a tissue as well as other parameters of cellular phenotype and physiology. Tight control of keratin expression implies the presence of complex regulatory landscapes within the keratin gene loci. Here, we highlight patterns of keratin expression in different biological conditions and summarize disparate data on mechanisms controlling keratin expression at the level of genomic regulatory elements, transcription factors (TFs), and chromatin spatial structure.
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8
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Li M, Peng L, Wang Z, Liu L, Cao M, Cui J, Wu F, Yang J. Roles of the cytoskeleton in human diseases. Mol Biol Rep 2023; 50:2847-2856. [PMID: 36609753 DOI: 10.1007/s11033-022-08025-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 10/12/2022] [Indexed: 01/08/2023]
Abstract
Recently, researches have revealed the key roles of the cytoskeleton in the occurrence and development of multiple diseases, suggesting that targeting the cytoskeleton is a viable approach for treating numerous refractory diseases. The cytoskeleton is a highly structured and complex network composed of actin filaments, microtubules, and intermediate filaments. In normal cells, these three cytoskeleton components are highly integrated and coordinated. However, the cytoskeleton undergoes drastic remodeling in cytoskeleton-related diseases, causing changes in cell polarity, affecting the cell cycle, leading to senescent diseases, and influencing cell migration to accelerate cancer metastasis. Additionally, mutations or abnormalities in cytoskeletal proteins and their related proteins are closely associated with several congenital diseases. Therefore, this review summarizes the roles of the cytoskeleton in cytoskeleton-related diseases as well as its potential roles in disease treatment to provide insights regarding the physiological functions and pathological roles of the cytoskeleton.
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Affiliation(s)
- Mengxin Li
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Cardiology and Endodontics, West China Hospital of Stomatology, Sichuan University, 610021, Chengdu, China
| | - Li Peng
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, 610065, Chengdu, China
| | - Zhenming Wang
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Cardiology and Endodontics, West China Hospital of Stomatology, Sichuan University, 610021, Chengdu, China
| | - Lijia Liu
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Cardiology and Endodontics, West China Hospital of Stomatology, Sichuan University, 610021, Chengdu, China
| | - Mengjiao Cao
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Cardiology and Endodontics, West China Hospital of Stomatology, Sichuan University, 610021, Chengdu, China
| | - Jingyao Cui
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Cardiology and Endodontics, West China Hospital of Stomatology, Sichuan University, 610021, Chengdu, China
| | - Fanzi Wu
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Cardiology and Endodontics, West China Hospital of Stomatology, Sichuan University, 610021, Chengdu, China
| | - Jing Yang
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Department of Cardiology and Endodontics, West China Hospital of Stomatology, Sichuan University, 610021, Chengdu, China.
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Giamarellos-Bourboulis EJ. Modulation of keratin deposition and pathogenesis of hidradenitis suppurativa: evidence coming from pachyonychia congenita. Br J Dermatol 2022; 187:e170-e171. [PMID: 35996837 DOI: 10.1111/bjd.21807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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10
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Treatment of Painful Palmoplantar Keratoderma Related to Pachyonychia Congenita Using EGFR Inhibitors. Biomedicines 2022; 10:biomedicines10040841. [PMID: 35453591 PMCID: PMC9028469 DOI: 10.3390/biomedicines10040841] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 03/27/2022] [Accepted: 03/31/2022] [Indexed: 12/29/2022] Open
Abstract
Pachyonychia congenita (PC) is a genodermatosis associated with severe painful palmoplantar keratoderma (PPK) and thickened dystrophic nails caused by autosomal dominant-negative mutations in five genes encoding keratins 6A-B-C, 16, and 17. The mechanical, surgical, or medical options for painful PC are inefficient. Given ErbB/Her family members’ role in epidermal homeostasis, this study sought to investigate the possibility of treating PC patients with PPK by blocking signaling either with EGFR (Her1) inhibitor erlotinib or lapatinib, a dual EGFR(Her1)/Her2. After 1 month of therapy with oral erlotinib treatment at 75 mg/day, the pain disappeared for patient #1, with partially reduced hyperkeratosis, while increasing the dose to 100 mg/day resulted in painful skin fissures. Therapy replacement with erlotinib cream at 0.2% was inconclusive, and substitution with oral lapatinib at alternating doses of 500 and 750 mg/day achieved a good compromise between pain reduction, symptom improvements, and side effects. Patient #2′s treatment with erlotinib cream failed to display significant improvements. Oral erlotinib started at 75 mg/day then reduced to 25 mg/day because of the formation of an acneiform rash. Treatment considerably improved the patient’s condition, with an almost complete disappearance of pain. Oral Her1 or 1/2 inhibitors reduced pain, improved two PC patients’ quality of life, and offered promising therapeutic perspectives.
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Ho M, Thompson B, Fisk JN, Nebert DW, Bruford EA, Vasiliou V, Bunick CG. Update of the keratin gene family: evolution, tissue-specific expression patterns, and relevance to clinical disorders. Hum Genomics 2022; 16:1. [PMID: 34991727 PMCID: PMC8733776 DOI: 10.1186/s40246-021-00374-9] [Citation(s) in RCA: 29] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2021] [Accepted: 12/17/2021] [Indexed: 12/15/2022] Open
Abstract
Intermediate filament (IntFil) genes arose during early metazoan evolution, to provide mechanical support for plasma membranes contacting/interacting with other cells and the extracellular matrix. Keratin genes comprise the largest subset of IntFil genes. Whereas the first keratin gene appeared in sponge, and three genes in arthropods, more rapid increases in keratin genes occurred in lungfish and amphibian genomes, concomitant with land animal-sea animal divergence (~ 440 to 410 million years ago). Human, mouse and zebrafish genomes contain 18, 17 and 24 non-keratin IntFil genes, respectively. Human has 27 of 28 type I "acidic" keratin genes clustered at chromosome (Chr) 17q21.2, and all 26 type II "basic" keratin genes clustered at Chr 12q13.13. Mouse has 27 of 28 type I keratin genes clustered on Chr 11, and all 26 type II clustered on Chr 15. Zebrafish has 18 type I keratin genes scattered on five chromosomes, and 3 type II keratin genes on two chromosomes. Types I and II keratin clusters-reflecting evolutionary blooms of keratin genes along one chromosomal segment-are found in all land animal genomes examined, but not fishes; such rapid gene expansions likely reflect sudden requirements for many novel paralogous proteins having divergent functions to enhance species survival following sea-to-land transition. Using data from the Genotype-Tissue Expression (GTEx) project, tissue-specific keratin expression throughout the human body was reconstructed. Clustering of gene expression patterns revealed similarities in tissue-specific expression patterns for previously described "keratin pairs" (i.e., KRT1/KRT10, KRT8/KRT18, KRT5/KRT14, KRT6/KRT16 and KRT6/KRT17 proteins). The ClinVar database currently lists 26 human disease-causing variants within the various domains of keratin proteins.
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Affiliation(s)
- Minh Ho
- Department of Dermatology, Yale University, 333 Cedar St., LCI 501, PO Box 208059, New Haven, CT, 06520-8059, USA
| | - Brian Thompson
- Department of Environmental Health Sciences, Yale School of Public Health, New Haven, CT, 06511, USA
| | - Jeffrey Nicholas Fisk
- Program of Computational Biology and Bioinformatics, Yale University, New Haven, CT, 06511, USA
| | - Daniel W Nebert
- Departments of Pediatrics and Molecular and Developmental Biology, Cincinnati Children's Research Center, Cincinnati, OH, 45229, USA
- Department of Environmental Health and Center for Environmental Genetics, University of Cincinnati College of Medicine, Cincinnati, OH, 45267, USA
| | - Elspeth A Bruford
- HUGO Gene Nomenclature Committee (HGNC), EMBL-EBI, Wellcome Genome Campus, Hinxton, Cambridge, CB10 1SD, UK
- Department of Haematology, University of Cambridge, Cambridge, CB2 0XY, UK
| | - Vasilis Vasiliou
- Department of Environmental Health Sciences, Yale School of Public Health, New Haven, CT, 06511, USA
| | - Christopher G Bunick
- Department of Dermatology, Yale University, 333 Cedar St., LCI 501, PO Box 208059, New Haven, CT, 06520-8059, USA.
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA.
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