{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,10]],"date-time":"2026-11-10T17:02:16Z","timestamp":1794330136517,"version":"4.9.0"},"reference-count":23,"publisher":"Springer Science and Business Media LLC","issue":"1","license":[{"start":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T00:00:00Z","timestamp":1769558400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,2,12]],"date-time":"2026-02-12T00:00:00Z","timestamp":1770854400000},"content-version":"vor","delay-in-days":15,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Infect Agents Cancer"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background &amp; aims<\/jats:title>\n                    <jats:p>Hepatitis B virus X protein (HBx) is a multifunctional viral regulator implicated in hepatocellular carcinoma (HCC). We aimed to characterize HBx mutations in liver tissue samples from Iranian patients with HCC and explore their potential structural and functional implications.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>Liver tissue samples from 10 patients with HCC and chronic HBV infection were analyzed using high-resolution melting (HRM) and Sanger sequencing. Detected variants were assessed by phylogenetic analysis, 3D protein modeling, and STRING-based protein\u2013protein interaction (PPI) mapping. Correlations with clinical and biochemical parameters were examined.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Multiple HBx mutations were identified, including a novel nonsense mutation at codon 135 (G135*), resulting in C-terminal truncation. Additional substitutions were found in the H-box (V88A, K94E, A100T), BH3-like motif (L113P, Q116R, E122K, A126T), and CCCH zinc-binding domain (C61S, C69R). Structural modeling predicted that these variants may potentially disrupt DDB1 and Bcl-2 interactions, as well as zinc coordination. STRING analysis suggested altered HBx connectivity with TP53, BAX, TNF, IL6, and CREB1, potentially affecting apoptosis, transcriptional regulation, and inflammatory signaling. Phylogenetic analysis confirmed that variants clustered within genotype D1, indicating intra-genotypic adaptation. Clinically, higher viral loads and HBeAg positivity were associated with elevated liver injury markers, consistent with the predicted functional impacts of these variants.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>HBx mutations in genotype D1, particularly the novel C-terminal truncation, may potentially influence viral persistence, apoptotic resistance, and oncogenic signaling in HCC, pending experimental validation. These findings highlight intra-genotypic HBx diversity as a potential biomarker and therapeutic target for HBV-related liver cancer.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Clinical trial number<\/jats:title>\n                    <jats:p>Not applicable.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1186\/s13027-026-00730-1","type":"journal-article","created":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T11:23:48Z","timestamp":1769599428000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Novel C-terminal HBx truncation (G135) in genotype D1 HBV: predicted effects on oncogenic signaling"],"prefix":"10.1186","volume":"21","author":[{"given":"Kamyar Mazloum","family":"Jalali","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hamidreza","family":"Mollaei","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chiman","family":"Karami","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elahe Mosayebnejad","family":"Roudbaneh","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,1,28]]},"reference":[{"issue":"4","key":"730_CR1","doi-asserted-by":"publisher","first-page":"741","DOI":"10.3390\/cells11040741","volume":"11","author":"E Sivasudhan","year":"2022","unstructured":"Sivasudhan E, Blake N, Lu Z, Meng J, Rong R. Hepatitis B viral protein HBx and the molecular mechanisms modulating the hallmarks of hepatocellular carcinoma: a comprehensive review. Cells. 2022;11(4):741.","journal-title":"Cells"},{"issue":"4","key":"730_CR2","doi-asserted-by":"publisher","first-page":"741","DOI":"10.1007\/s12072-022-10351-6","volume":"16","author":"L Yang","year":"2022","unstructured":"Yang L, Zou T, Chen Y, Zhao Y, Wu X, Li M, et al. Hepatitis B virus X protein mediated epigenetic alterations in the pathogenesis of hepatocellular carcinoma. Hep Intl. 2022;16(4):741\u201354.","journal-title":"Hep Intl"},{"key":"730_CR3","doi-asserted-by":"publisher","unstructured":"Ramakrishnan D, Xing W, Beran RK, Chemuru S, Rohrs H, Niedziela-Majka A, et al. Hepatitis B virus X protein function requires zinc binding. J Virol. 2019;93(16). https:\/\/doi.org\/10.1128\/jvi. 00250\u2009\u2013\u200919.","DOI":"10.1128\/jvi"},{"issue":"4","key":"730_CR4","first-page":"554","volume":"14","author":"C Karami","year":"2022","unstructured":"Karami C, Mollaei H, Arabzadeh SA, Amerkani S, Pashangzadeh S, Nikpour N. The mutations frequency of enhancer II\/HBx regions of hepatitis B virus in acutely infected Iranian patients: a cross-sectional study. Iran J Microbiol. 2022;14(4):554.","journal-title":"Iran J Microbiol"},{"key":"730_CR5","doi-asserted-by":"crossref","unstructured":"Tanaka H, Diogo Dias J, Jay B, Kita S, Sasaki M, Takeda H et al. Structural basis of the hepatitis B virus X protein in complex with DDB1. Proceedings of the National Academy of Sciences. 2025;122(24):e2421325122.","DOI":"10.1073\/pnas.2421325122"},{"key":"730_CR6","unstructured":"Rosenkranz AL. Determining secondary structural elements of hepatitis B virus pregenomic RNA and preliminary analysis of the DDB1-HBx interaction as a therapeutic target. Drexel University; 2023."},{"issue":"5","key":"730_CR7","doi-asserted-by":"publisher","first-page":"632","DOI":"10.1021\/acs.biochem.3c00709","volume":"63","author":"H Kusunoki","year":"2024","unstructured":"Kusunoki H, Sakamoto T, Kobayashi N, Kohno T, Wakamatsu K, Nagata T. Structural insights into the interaction between the C-terminal-deleted BH3-like motif peptide of hepatitis B virus X protein and Bcl-xL. Biochemistry. 2024;63(5):632\u201343.","journal-title":"Biochemistry"},{"issue":"1","key":"730_CR8","doi-asserted-by":"publisher","first-page":"2421231","DOI":"10.1080\/21505594.2024.2421231","volume":"15","author":"Y Zhang","year":"2024","unstructured":"Zhang Y, Cao W, Wang S, Zhang L, Li X, Zhang Z, et al. Epigenetic modification of hepatitis B virus infection and related hepatocellular carcinoma. Virulence. 2024;15(1):2421231.","journal-title":"Virulence"},{"key":"730_CR9","doi-asserted-by":"publisher","first-page":"32","DOI":"10.1016\/j.coviro.2018.01.007","volume":"30","author":"BL Slagle","year":"2018","unstructured":"Slagle BL, Bouchard MJ. Role of HBx in hepatitis B virus persistence and its therapeutic implications. Curr Opin Virol. 2018;30:32\u20138.","journal-title":"Curr Opin Virol"},{"key":"730_CR10","doi-asserted-by":"crossref","unstructured":"Yuan H, Zhao L, Yang G, Zhang S, Lv P, Zhang S et al. HBx-induced HSPB1 is a potential therapeutic target owing to its modulation of HBV CccDNA and hepatic immune responses. J Hepatol. 2025.","DOI":"10.1016\/j.jhep.2025.09.033"},{"issue":"7594","key":"730_CR11","doi-asserted-by":"publisher","first-page":"386","DOI":"10.1038\/nature17170","volume":"531","author":"A Decorsi\u00e8re","year":"2016","unstructured":"Decorsi\u00e8re A, Mueller H, Van Breugel PC, Abdul F, Gerossier L, Beran RK, et al. Hepatitis B virus X protein identifies the Smc5\/6 complex as a host restriction factor. Nature. 2016;531(7594):386\u20139.","journal-title":"Nature"},{"issue":"9","key":"730_CR12","doi-asserted-by":"publisher","first-page":"1361","DOI":"10.3390\/v16091361","volume":"16","author":"D Li","year":"2024","unstructured":"Li D, Hamadalnil Y, Tu T. Hepatitis B viral protein hbx: roles in viral replication and hepatocarcinogenesis. Viruses. 2024;16(9):1361.","journal-title":"Viruses"},{"issue":"6","key":"730_CR13","doi-asserted-by":"publisher","first-page":"1147","DOI":"10.1038\/s41388-020-01593-5","volume":"40","author":"Y Zhang","year":"2021","unstructured":"Zhang Y, Yan Q, Gong L, Xu H, Liu B, Fang X, et al. C-terminal truncated HBx initiates hepatocarcinogenesis by downregulating TXNIP and reprogramming glucose metabolism. Oncogene. 2021;40(6):1147\u201361.","journal-title":"Oncogene"},{"issue":"4","key":"730_CR14","doi-asserted-by":"publisher","first-page":"1166","DOI":"10.3390\/biomedicines11041166","volume":"11","author":"E Kouroumalis","year":"2023","unstructured":"Kouroumalis E, Tsomidis I, Voumvouraki A. Pathogenesis of hepatocellular carcinoma: the interplay of apoptosis and autophagy. Biomedicines. 2023;11(4):1166.","journal-title":"Biomedicines"},{"issue":"19","key":"730_CR15","doi-asserted-by":"publisher","first-page":"4890","DOI":"10.12998\/wjcc.v9.i19.4890","volume":"9","author":"GO Elpek","year":"2021","unstructured":"Elpek GO. Molecular pathways in viral hepatitis-associated liver carcinogenesis: an update. World J Clin Cases. 2021;9(19):4890.","journal-title":"World J Clin Cases"},{"key":"730_CR16","doi-asserted-by":"publisher","first-page":"110199","DOI":"10.1016\/j.virol.2024.110199","volume":"599","author":"A Kar","year":"2024","unstructured":"Kar A, Mukherjee S, Mukherjee S, Biswas A. Ubiquitin: a double-edged sword in hepatitis B virus-induced hepatocellular carcinoma. Virology. 2024;599:110199.","journal-title":"Virology"},{"issue":"5","key":"730_CR17","doi-asserted-by":"publisher","first-page":"4964","DOI":"10.3390\/ijms24054964","volume":"24","author":"A Schollmeier","year":"2023","unstructured":"Schollmeier A, Glitscher M, Hildt E. Relevance of HBx for hepatitis B virus-associated pathogenesis. Int J Mol Sci. 2023;24(5):4964.","journal-title":"Int J Mol Sci"},{"issue":"1","key":"730_CR18","doi-asserted-by":"publisher","first-page":"553","DOI":"10.1186\/s12879-022-07528-7","volume":"22","author":"F Farshadpour","year":"2022","unstructured":"Farshadpour F, Taherkhani R, Saberi F. Molecular evaluation of hepatitis B virus infection and predominant mutations of pre-core, basal core promoter and S regions in an Iranian population with type 2 diabetes mellitus: a case\u2013control study. BMC Infect Dis. 2022;22(1):553.","journal-title":"BMC Infect Dis"},{"key":"730_CR19","doi-asserted-by":"publisher","first-page":"116","DOI":"10.1111\/liv.15338","volume":"43","author":"JV Lazarus","year":"2023","unstructured":"Lazarus JV, Al-Rifai A, Sanai FM, Alghamdi AS, Sharara AI, Saad MF, et al. Hepatitis delta virus infection prevalence, diagnosis and treatment in the middle east: A scoping review. Liver Int. 2023;43:116\u201323.","journal-title":"Liver Int"},{"issue":"4","key":"730_CR20","doi-asserted-by":"publisher","first-page":"1125","DOI":"10.7150\/ijbs.55724","volume":"17","author":"X Jiang","year":"2021","unstructured":"Jiang X, Chang L, Yan Y, Wang L. Paradoxical HBsAg and anti-HBs coexistence among chronic HBV infections: causes and consequences. 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J Virol. 2024;98(8):e00332\u201324.","journal-title":"J Virol"},{"issue":"5","key":"730_CR23","doi-asserted-by":"publisher","first-page":"986","DOI":"10.3390\/v14050986","volume":"14","author":"GEM Rizzo","year":"2022","unstructured":"Rizzo GEM, Cabibbo G, Craxi A. Hepatitis B virus-associated hepatocellular carcinoma. Viruses. 2022;14(5):986.","journal-title":"Viruses"}],"container-title":["Infectious Agents and Cancer"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/link.springer.com\/article\/10.1186\/s13027-026-00730-1","content-type":"text\/html","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1186\/s13027-026-00730-1.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/link.springer.com\/content\/pdf\/10.1186\/s13027-026-00730-1.pdf","content-type":"application\/pdf","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,16]],"date-time":"2026-06-16T17:15:40Z","timestamp":1781630140000},"score":1,"resource":{"primary":{"URL":"https:\/\/link.springer.com\/10.1186\/s13027-026-00730-1"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,1,28]]},"references-count":23,"journal-issue":{"issue":"1","published-online":{"date-parts":[[2026,12]]}},"alternative-id":["730"],"URL":"https:\/\/doi.org\/10.1186\/s13027-026-00730-1","relation":{},"ISSN":["1750-9378"],"issn-type":[{"value":"1750-9378","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,1,28]]},"assertion":[{"value":"16 October 2025","order":1,"name":"received","label":"Received","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"9 January 2026","order":2,"name":"accepted","label":"Accepted","group":{"name":"ArticleHistory","label":"Article History"}},{"value":"28 January 2026","order":3,"name":"first_online","label":"First Online","group":{"name":"ArticleHistory","label":"Article History"}},{"order":1,"name":"Ethics","group":{"name":"EthicsHeading","label":"Declarations"}},{"value":"This study was conducted using archived serum samples from HBV-HCC patients collected for diagnostic purposes at Kerman University of Medical Sciences, Iran. All samples were fully anonymized prior to analysis. Ethical approval was obtained from the Ethics Committee of Kerman University of Medical Sciences (Approval ID: IR.KMU.REC.96000733). Given the retrospective and anonymized nature of the study, the requirement for written informed consent was waived in accordance with institutional and national regulations, and with the Declaration of Helsinki.","order":2,"name":"Ethics","group":{"name":"EthicsHeading","label":"Ethical approval and consent to participate"}},{"value":"As this report was based on fully anonymized archival samples with no identifying information, specific consent for publication was not required.","order":3,"name":"Ethics","group":{"name":"EthicsHeading","label":"Consent for publication"}},{"value":"The authors declare no competing interests.","order":4,"name":"Ethics","group":{"name":"EthicsHeading","label":"Competing interests"}}],"article-number":"17"}}