Atlas of Genetics and Cytogenetics in Oncology and Haematology

Home   Genes   Leukemias   Solid Tumors   Cancer-Prone   Deep Insight   Case Reports   Journals  Portal   Teaching   

X Y 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 NA

RAD9A (RAD9 homolog A (S. pombe))

Written2010-03Vivian Chan
Department of Medicine, The University of Hong Kong, Queen Mary Hospital, Pokfulam Road, Hong Kong, China

(Note : for Links provided by Atlas : click)


Alias (NCBI)RAD9
HGNC Previous nameRAD9
HGNC Previous nameRAD9 (S. pombe) homolog
 RAD9 homolog A (S. pombe)
LocusID (NCBI) 5883
Atlas_Id 42031
Location 11q13.2  [Link to chromosome band 11q13]
Location_base_pair Starts at 67391986 and ends at 67398410 bp from pter ( according to GRCh38/hg38-Dec_2013)  [Mapping RAD9A.png]
Fusion genes
(updated 2017)
Data from Atlas, Mitelman, Cosmic Fusion, Fusion Cancer, TCGA fusion databases with official HUGO symbols (see references in chromosomal bands)
PDXK (21q22.3)::RAD9A (11q13.2)RAD9A (11q13.2)::PPP1CA (11q13.2)
Note Accession No. NM_004584.


Description 6461 bp, 11 exons.
Transcription The transcript length is 1176 bp, full open reading frame cDNA clone, encodes a 391 amino acid, 42520 Da protein (Lieberman et al., 1996).


  (Adapted from Ishikawa K et al., Current Genomics.2006:7:477-80).
Function The gene product is highly similar to Rad9 protein from S pombe. A cell cycle checkpoint protein with multiple functions for preserving genomic integrity (Ishikawa et al., 2006), such as the regulation of DNA damage response, cell cycle checkpoint, DNA repair, apoptosis, transcriptional regulation, exonuclease activity, ribonucleotide synthesis and embryogenesis.
hRad9 forms ring-shape heterotrimeric complex with hRad1 and hHus1 proteins (9-1-1 complex). All 3 proteins have sequence homology with proliferating cell nuclear antigen (PCNA). The 9-1-1 complex is recruited onto DNA-lesion by RAD17 and ATR - triggering checkpoint signaling pathway and acts to repair DNA damage (Volkmer and Karnitz, 1999; Rauen et al., 2000; Zou et al., 2002; Medhurst et al., 2008). Phosphorylation of hRad9 by protein kinase C delta (PKCD) is necessary for the formation of the 9-1-1 complex (Yoshida et al., 2003).
NH2 terminus of hRad9 contains BH3-like domain which binds antiapoptotic proteins BCL2 and Bcl-x2, thereby promoting apoptosis (Komatsu et al., 2000). This interaction of hRad9 to Bcl2 is regulated also by PKCdelta (Yoshida et al., 2003).
RAD9, like P53 can regulate P21 at the transcriptional level. Overexpression of hRad was shown to cause an increase in P21 RNA and the encoded protein level in P53-null H1299 cells (Yin et al., 2004). This suggests that hRAD9 and P53 coregulate P21 to direct cell cycle progression. hRAD9 may also modulate transcription of other down-stream target genes.
C-terminal region of hRad9 protein acts to transport 9-1-1 complex into the nucleus (Hirai and Wang, 2002; Sohn and Cho, 2009). hRad9 and ATM rapidly colocalize to regions containing DNA double-stranded breaks after DNA-damage (Greer et al., 2003; Medhurst et al., 2008) and Atm can phosphorylate Rad9 directly at Ser-272 during ionizing radiation (IR)-induced G1/S checkpoint activation (Chen et al., 2001).
The 9-1-1 complex may attract DNA polymerase beta to sites of DNA damage, thus connecting checkpoint and DNA repair (Toueille et al., 2004).
Thr-292 of hRad9 is subject to CDC2-dependent phosphorylation in mitosis. Four other hRad9 phosphorylation sites (Ser-277, Ser-328, Ser-336 and Thr-355) are regulated in part by Cdc2 (St Onge et al., 2001; St Onge et al., 2003; Ishikawa et al., 2006).
Phosphorylation sites of the C-terminal region of hRad9 are essential for CHK1 activation following hydroxyurea, ionizing radiation and ultraviolet treatment (Roos-Mattjus et al., 2003).
Crystal structure of the human Rad9-Hus1-Rad1 complex reveals a single repair enzyme binding site (Doré et al., 2009) and suggests that the C-terminal end of Rad9 protein is involved in the regulation of the complex in DNA binding (Sohn and Cho, 2009).
hRad9 possesses 3'-5' exonuclease activity which may contribute to its role in sensing and repairing DNA damage (Bessho and Sancar, 2000). The exact mechanism of this exonucleolytic processing is still unclear.

Implicated in

Entity Various cancers
Oncogenesis Checkpoint genes are known to be involved in the maintenance of genomic integrity and their aberrant expression can lead to cancer. Paralogue of human HRad9 is called HRad9B. Gene product is structurally related to hRad9 protein (55% similar and 35% identical). HRad9B gene is expressed predominantly in the testis and found in decreased amount in testicular tumours, particularly seminomas (Hopkins et al., 2003).
Entity Prostate cancer
Oncogenesis Carboxy terminus of hRad9 contains a FXXLF motif which interrupts the androgen-induced interaction between the C and N terminus of androgen receptor (AR), acting as a co-regulator to suppress androgen-AR transactivation in prostrate cancer cells (Wang et al., 2004). This denotes a possible tumour suppressor function of hRad9.
Recent study has confirmed that high levels of Rad9 expression is found in prostate cancer cells and the high protein levels in prostate adenocarcinomas were generally associated with more advanced disease (Zhu et al., 2008). Similar to previous findings in breast cancer (Cheng et al., 2005), the increased expression of Rad9 in prostate cancer cells was in part due to aberrant methylation or gene amplification (Zhu et al., 2008). The study failed to show that the role of Rad9 in prostate tumorigenesis was androgen dependent, since both androgen dependent CWR22 and LNCaP cell lines as well as androgen independent DU145 and PC-3 cell lines were found to contain high levels of Rad9 protein (Zhu et al., 2008).
Entity Lung cancer
Oncogenesis Presence of hyperphosphorylated forms of hRad9 has been found in the nuclei of surgically resected primary lung carcinoma cells (Maniwa et al., 2005). No mutation of the hRad9 gene was found in lung cancer cells, but a nonsynonymous single nucleotide polymorphism (SNP), His239Arg was found in 8 out of 50 lung adenocarcinoma patients, suggesting a possible association of this SNP with the development of cancer (Maniwa et al., 2006).
Entity Breast cancer
Oncogenesis Over-expression of hRad9 mRNA was found in breast cancer, which was shown to be correlated with tumour size (p = 0.037) and local recurrence (p = 0.033). Over-expression of Rad9 mRNA was partly due to increase in RAD9 gene amplification and aberrant DNA methylation at a putative Sp 1/3 binding site within the second intron of the RAD9 gene. Promoter assays indicate that the Sp 1/3 site in intron 2 may act as a silencer. Further experiments in silencing Rad9 expression by RNAi inhibit the proliferation of MCF-7 cell line in vitro. These findings suggested that Rad9 is a new oncogene candidate on Ch11q13 with a role in breast cancer progression (Cheng et al., 2005).
In contrast to previous findings in testicular tumours, increased hRad9 protein was found in the nuclei of breast cancer cells. These were shown to exist as hyperphosphorylated forms, with molecular weights of 65 and 50 kDa. Since the theoretical molecular weight of hRad9 is 45 kDa (Lindsey-Boltz et al., 2001), these larger forms most likely represent hyperphosphorylated hRad9 and its hRad9-hRad1-hHus1 complex (Chan et al., 2008; St Onge et al., 1999). Localization of hyperphosphorylated forms of hRad in the nucleus of cancer cells is in keeping with its function in ameliorating DNA instability, whereby it inadvertently assists tumour growth.
Entity Colorectal cancer
Oncogenesis Rad9 interacts physically within the DNA mismatch repair (MMR) protein MLH1. Disruption of the interaction by a single point mutation in Rad9 leads to significantly reduced mismatch repair activity (He et al., 2008). The Rad9-MHL1 interaction might be a hotspot for mutation in tumour cells. The hMLH1 mutations lead to hereditary non-polyposis colorectal cancer (HNPCC) (Avdievich et al., 2008; Peltomäki et al., 2004) and various types of tumours (Avdievich et al., 2008; Hu et al., 2008). However, hRad9's function in MMR is not in the 9-1-1-complex form (He et al., 2008).


Distinct effects of the recurrent Mlh1G67R mutation on MMR functions, cancer, and meiosis.
Avdievich E, Reiss C, Scherer SJ, Zhang Y, Maier SM, Jin B, Hou H Jr, Rosenwald A, Riedmiller H, Kucherlapati R, Cohen PE, Edelmann W, Kneitz B.
Proc Natl Acad Sci U S A. 2008 Mar 18;105(11):4247-52. Epub 2008 Mar 12.
PMID 18337503
Human DNA damage checkpoint protein hRAD9 is a 3' to 5' exonuclease.
Bessho T, Sancar A.
J Biol Chem. 2000 Mar 17;275(11):7451-4.
PMID 10713044
Localization of hRad9 in breast cancer.
Chan V, Khoo US, Wong MS, Lau K, Suen D, Li G, Kwong A, Chan TK.
BMC Cancer. 2008 Jul 11;8:196.
PMID 18616832
ATM-dependent phosphorylation of human Rad9 is required for ionizing radiation-induced checkpoint activation.
Chen MJ, Lin YT, Lieberman HB, Chen G, Lee EY.
J Biol Chem. 2001 May 11;276(19):16580-6. Epub 2001 Feb 6.
PMID 11278446
The cell cycle checkpoint gene Rad9 is a novel oncogene activated by 11q13 amplification and DNA methylation in breast cancer.
Cheng CK, Chow LW, Loo WT, Chan TK, Chan V.
Cancer Res. 2005 Oct 1;65(19):8646-54.
PMID 16204032
Crystal structure of the rad9-rad1-hus1 DNA damage checkpoint complex--implications for clamp loading and regulation.
Dore AS, Kilkenny ML, Rzechorzek NJ, Pearl LH.
Mol Cell. 2009 Jun 26;34(6):735-45. Epub 2009 May 14.
PMID 19446481
hRad9 rapidly binds DNA containing double-strand breaks and is required for damage-dependent topoisomerase II beta binding protein 1 focus formation.
Greer DA, Besley BD, Kennedy KB, Davey S.
Cancer Res. 2003 Aug 15;63(16):4829-35.
PMID 12941802
Rad9 plays an important role in DNA mismatch repair through physical interaction with MLH1.
He W, Zhao Y, Zhang C, An L, Hu Z, Liu Y, Han L, Bi L, Xie Z, Xue P, Yang F, Hang H.
Nucleic Acids Res. 2008 Nov;36(20):6406-17. Epub 2008 Oct 8.
PMID 18842633
A role of the C-terminal region of human Rad9 (hRad9) in nuclear transport of the hRad9 checkpoint complex.
Hirai I, Wang HG.
J Biol Chem. 2002 Jul 12;277(28):25722-7. Epub 2002 May 6.
PMID 11994305
Expression of mammalian paralogues of HRAD9 and Mrad9 checkpoint control genes in normal and cancerous testicular tissue.
Hopkins KM, Wang X, Berlin A, Hang H, Thaker HM, Lieberman HB.
Cancer Res. 2003 Sep 1;63(17):5291-8.
PMID 14500360
Targeted deletion of Rad9 in mouse skin keratinocytes enhances genotoxin-induced tumor development.
Hu Z, Liu Y, Zhang C, Zhao Y, He W, Han L, Yang L, Hopkins KM, Yang X, Lieberman HB, Hang H.
Cancer Res. 2008 Jul 15;68(14):5552-61.
PMID 18632607
Multiple functions of rad9 for preserving genomic integrity.
Ishikawa K, Ishii H, Saito T, Ichimura K.
Curr Genomics. 2006;7(8):477-80.
PMID 18369403
Human homologue of S. pombe Rad9 interacts with BCL-2/BCL-xL and promotes apoptosis.
Komatsu K, Miyashita T, Hang H, Hopkins KM, Zheng W, Cuddeback S, Yamada M, Lieberman HB, Wang HG.
Nat Cell Biol. 2000 Jan;2(1):1-6.
PMID 10620799
A human homolog of the Schizosaccharomyces pombe rad9+ checkpoint control gene.
Lieberman HB, Hopkins KM, Nass M, Demetrick D, Davey S.
Proc Natl Acad Sci U S A. 1996 Nov 26;93(24):13890-5.
PMID 8943031
Purification and characterization of human DNA damage checkpoint Rad complexes.
Lindsey-Boltz LA, Bermudez VP, Hurwitz J, Sancar A.
Proc Natl Acad Sci U S A. 2001 Sep 25;98(20):11236-41.
PMID 11572977
His239Arg SNP of HRAD9 is associated with lung adenocarcinoma.
Maniwa Y, Yoshimura M, Bermudez VP, Okada K, Kanomata N, Ohbayashi C, Nishimura Y, Hayashi Y, Hurwitz J, Okita Y.
Cancer. 2006 Mar 1;106(5):1117-22.
PMID 16444745
ATR and Rad17 collaborate in modulating Rad9 localisation at sites of DNA damage.
Medhurst AL, Warmerdam DO, Akerman I, Verwayen EH, Kanaar R, Smits VA, Lakin ND.
J Cell Sci. 2008 Dec 1;121(Pt 23):3933-40.
PMID 19020305
Mutations associated with HNPCC predisposition -- Update of ICG-HNPCC/INSiGHT mutation database.
Peltomaki P, Vasen H.
Dis Markers. 2004;20(4-5):269-76. (REVIEW)
PMID 15528792
The human checkpoint protein hRad17 interacts with the PCNA-like proteins hRad1, hHus1, and hRad9.
Rauen M, Burtelow MA, Dufault VM, Karnitz LM.
J Biol Chem. 2000 Sep 22;275(38):29767-71.
PMID 10884395
Phosphorylation of human Rad9 is required for genotoxin-activated checkpoint signaling.
Roos-Mattjus P, Hopkins KM, Oestreich AJ, Vroman BT, Johnson KL, Naylor S, Lieberman HB, Karnitz LM.
J Biol Chem. 2003 Jul 4;278(27):24428-37. Epub 2003 Apr 21.
PMID 12709442
Crystal structure of the human rad9-hus1-rad1 clamp.
Sohn SY, Cho Y.
J Mol Biol. 2009 Jul 17;390(3):490-502. Epub 2009 May 21.
PMID 19464297
A role for the phosphorylation of hRad9 in checkpoint signaling.
St Onge RP, Besley BD, Pelley JL, Davey S.
J Biol Chem. 2003 Jul 18;278(29):26620-8. Epub 2003 May 6.
PMID 12734188
The human Rad9/Rad1/Hus1 damage sensor clamp interacts with DNA polymerase beta and increases its DNA substrate utilisation efficiency: implications for DNA repair.
Toueille M, El-Andaloussi N, Frouin I, Freire R, Funk D, Shevelev I, Friedrich-Heineken E, Villani G, Hottiger MO, Hubscher U.
Nucleic Acids Res. 2004 Jun 22;32(11):3316-24. Print 2004.
PMID 15314187
Human homologs of Schizosaccharomyces pombe rad1, hus1, and rad9 form a DNA damage-responsive protein complex.
Volkmer E, Karnitz LM.
J Biol Chem. 1999 Jan 8;274(2):567-70.
PMID 9872989
Human checkpoint protein hRad9 functions as a negative coregulator to repress androgen receptor transactivation in prostate cancer cells.
Wang L, Hsu CL, Ni J, Wang PH, Yeh S, Keng P, Chang C.
Mol Cell Biol. 2004 Mar;24(5):2202-13.
PMID 14966297
Human RAD9 checkpoint control/proapoptotic protein can activate transcription of p21.
Yin Y, Zhu A, Jin YJ, Liu YX, Zhang X, Hopkins KM, Lieberman HB.
Proc Natl Acad Sci U S A. 2004 Jun 15;101(24):8864-9. Epub 2004 Jun 7.
PMID 15184659
Protein kinase Cdelta is responsible for constitutive and DNA damage-induced phosphorylation of Rad9.
Yoshida K, Wang HG, Miki Y, Kufe D.
EMBO J. 2003 Mar 17;22(6):1431-41.
PMID 12628935
Rad9 has a functional role in human prostate carcinogenesis.
Zhu A, Zhang CX, Lieberman HB.
Cancer Res. 2008 Mar 1;68(5):1267-74.
PMID 18316588
Regulation of ATR substrate selection by Rad17-dependent loading of Rad9 complexes onto chromatin.
Zou L, Cortez D, Elledge SJ.
Genes Dev. 2002 Jan 15;16(2):198-208.
PMID 11799063


This paper should be referenced as such :
Chan, V. RAD9A (RAD9 homolog A (S
Atlas Genet Cytogenet Oncol Haematol. 2010;14(12):1145-1148.
Free journal version : [ pdf ]   [ DOI ]

External links


HGNC (Hugo)RAD9A   9827
Atlas Explorer : (Salamanque)RAD9A
Entrez_Gene (NCBI)RAD9A    RAD9 checkpoint clamp component A
GeneCards (Weizmann)RAD9A
Ensembl hg19 (Hinxton)ENSG00000172613 [Gene_View]
Ensembl hg38 (Hinxton)ENSG00000172613 [Gene_View]  ENSG00000172613 [Sequence]  chr11:67391986-67398410 [Contig_View]  RAD9A [Vega]
ICGC DataPortalENSG00000172613
TCGA cBioPortalRAD9A
Genatlas (Paris)RAD9A
SOURCE (Princeton)RAD9A
Genetics Home Reference (NIH)RAD9A
Genomic and cartography
GoldenPath hg38 (UCSC)RAD9A  -     chr11:67391986-67398410 +  11q13.2   [Description]    (hg38-Dec_2013)
GoldenPath hg19 (UCSC)RAD9A  -     11q13.2   [Description]    (hg19-Feb_2009)
GoldenPathRAD9A - 11q13.2 [CytoView hg19]  RAD9A - 11q13.2 [CytoView hg38]
Genome Data Viewer NCBIRAD9A [Mapview hg19]  
Gene and transcription
Genbank (Entrez)AA708970 AK310213 AK315348 BC014848 CB164642
RefSeq transcript (Entrez)NM_001243224 NM_004584
Consensus coding sequences : CCDS (NCBI)RAD9A
Gene ExpressionRAD9A [ NCBI-GEO ]   RAD9A [ EBI - ARRAY_EXPRESS ]   RAD9A [ SEEK ]   RAD9A [ MEM ]
Gene Expression Viewer (FireBrowse)RAD9A [ Firebrowse - Broad ]
GenevisibleExpression of RAD9A in : [tissues]  [cell-lines]  [cancer]  [perturbations]  
BioGPS (Tissue expression)5883
GTEX Portal (Tissue expression)RAD9A
Human Protein AtlasENSG00000172613-RAD9A [pathology]   [cell]   [tissue]
Protein : pattern, domain, 3D structure
UniProt/SwissProtQ99638   [function]  [subcellular_location]  [family_and_domains]  [pathology_and_biotech]  [ptm_processing]  [expression]  [interaction]
NextProtQ99638  [Sequence]  [Exons]  [Medical]  [Publications]
With graphics : InterProQ99638
Catalytic activity : Enzyme3.1.11.2 [ Enzyme-Expasy ] [ IntEnz-EBI ] [ BRENDA ] [ KEGG ]   [ MEROPS ]
Domains : Interpro (EBI)Rad9    Rad9/Ddc1   
Domain families : Pfam (Sanger)Rad9 (PF04139)   
Domain families : Pfam (NCBI)pfam04139   
Conserved Domain (NCBI)RAD9A
PDB (RSDB)3A1J    3G65    3GGR    6HM5    6J8Y   
PDB Europe3A1J    3G65    3GGR    6HM5    6J8Y   
PDB (PDBSum)3A1J    3G65    3GGR    6HM5    6J8Y   
PDB (IMB)3A1J    3G65    3GGR    6HM5    6J8Y   
Structural Biology KnowledgeBase3A1J    3G65    3GGR    6HM5    6J8Y   
SCOP (Structural Classification of Proteins)3A1J    3G65    3GGR    6HM5    6J8Y   
CATH (Classification of proteins structures)3A1J    3G65    3GGR    6HM5    6J8Y   
AlphaFold pdb e-kbQ99638   
Human Protein Atlas [tissue]ENSG00000172613-RAD9A [tissue]
Protein Interaction databases
IntAct (EBI)Q99638
Complex Portal (EBI)Q99638 CPX-1829 Checkpoint clamp complex
Ontologies - Pathways
Ontology : AmiGODNA replication checkpoint signaling  DNA damage checkpoint signaling  protein binding  nucleus  nucleoplasm  nucleoplasm  DNA replication  DNA repair  cellular response to DNA damage stimulus  3'-5' exonuclease activity  exodeoxyribonuclease III activity  SH3 domain binding  enzyme binding  protein kinase binding  checkpoint clamp complex  mitotic intra-S DNA damage checkpoint signaling  histone deacetylase binding  cellular response to ionizing radiation  cellular response to ionizing radiation  nucleic acid phosphodiester bond hydrolysis  regulation of signal transduction by p53 class mediator  
Ontology : EGO-EBIDNA replication checkpoint signaling  DNA damage checkpoint signaling  protein binding  nucleus  nucleoplasm  nucleoplasm  DNA replication  DNA repair  cellular response to DNA damage stimulus  3'-5' exonuclease activity  exodeoxyribonuclease III activity  SH3 domain binding  enzyme binding  protein kinase binding  checkpoint clamp complex  mitotic intra-S DNA damage checkpoint signaling  histone deacetylase binding  cellular response to ionizing radiation  cellular response to ionizing radiation  nucleic acid phosphodiester bond hydrolysis  regulation of signal transduction by p53 class mediator  
Pathways : BIOCARTARole of BRCA1, BRCA2 and ATR in Cancer Susceptibility [Genes]   
REACTOMEQ99638 [protein]
REACTOME PathwaysR-HSA-69473 [pathway]   
NDEx NetworkRAD9A
Atlas of Cancer Signalling NetworkRAD9A
Wikipedia pathwaysRAD9A
Orthology - Evolution
GeneTree (enSembl)ENSG00000172613
Phylogenetic Trees/Animal Genes : TreeFamRAD9A
Homologs : HomoloGeneRAD9A
Homology/Alignments : Family Browser (UCSC)RAD9A
Gene fusions - Rearrangements
Fusion : QuiverRAD9A
Polymorphisms : SNP and Copy number variants
NCBI Variation ViewerRAD9A [hg38]
dbSNP Single Nucleotide Polymorphism (NCBI)RAD9A
Exome Variant ServerRAD9A
GNOMAD BrowserENSG00000172613
Varsome BrowserRAD9A
ACMGRAD9A variants
Genomic Variants (DGV)RAD9A [DGVbeta]
DECIPHERRAD9A [patients]   [syndromes]   [variants]   [genes]  
CONAN: Copy Number AnalysisRAD9A 
ICGC Data PortalRAD9A 
TCGA Data PortalRAD9A 
Broad Tumor PortalRAD9A
OASIS PortalRAD9A [ Somatic mutations - Copy number]
Somatic Mutations in Cancer : COSMICRAD9A  [overview]  [genome browser]  [tissue]  [distribution]  
Somatic Mutations in Cancer : COSMIC3DRAD9A
Mutations and Diseases : HGMDRAD9A
LOVD (Leiden Open Variation Database)[gene] [transcripts] [variants]
DgiDB (Drug Gene Interaction Database)RAD9A
DoCM (Curated mutations)RAD9A
CIViC (Clinical Interpretations of Variants in Cancer)RAD9A
NCG (London)RAD9A
Impact of mutations[PolyPhen2] [Provean] [Buck Institute : MutDB] [Mutation Assessor] [Mutanalyser]
Genetic Testing Registry RAD9A
NextProtQ99638 [Medical]
Target ValidationRAD9A
Huge Navigator RAD9A [HugePedia]
Clinical trials, drugs, therapy
Protein Interactions : CTDRAD9A
Pharm GKB GenePA294
Clinical trialRAD9A
DataMed IndexRAD9A
PubMed129 Pubmed reference(s) in Entrez
GeneRIFsGene References Into Functions (Entrez)
REVIEW articlesautomatic search in PubMed
Last year publicationsautomatic search in PubMed

Search in all EBI   NCBI

© Atlas of Genetics and Cytogenetics in Oncology and Haematology
indexed on : Mon Jan 17 15:39:46 CET 2022

Home   Genes   Leukemias   Solid Tumors   Cancer-Prone   Deep Insight   Case Reports   Journals  Portal   Teaching   

For comments and suggestions or contributions, please contact us