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Buchakjian, M.

Publications and source records attributed to Buchakjian, M..

2 recordsLinked to original sources

Spatiotemporal Heterogeneity of HPV Integration Architectures Drive Oncogenic Features of Oropharyngeal Cancer

Viral integration is common in human papillomavirus-positive oropharyngeal squamous cell carcinoma (HPV+ OPSCC), but its structural and clinical significance remains unclear. We integrated targeted capture sequencing of 197 HPV+ OPSCCs with long-read nanopore sequencing of 17 tumors and models to characterize HPV-host rearrangements. We developed a novel quantitative informatics framework that classifies integration structures as Type1 (simple, single/low-copy) or Type2 (clustered, high-copy, rearranged). HPV integration occurred in 83% of tumors, with recurrent hotspots including TP63, MYC, CD274, TRAF2, and KMT2C. Type2 events were enriched for HPV E2 disruption, focal human amplifications, preferential transcription, and noncanonical HPV-host RNA fusion isoforms. Type2 tumors showed increased HPV oncogene expression and activation of MYC, NF-{kappa}B/TNF, PI3K-AKT-mTOR, Hippo/YAP-TAZ, and epithelial stemness programs. Multi-region and longitudinal analyses revealed intratumoral heterogeneity and clonal selection of Type2 architectures during progression, supporting integration structure as a potential marker of aggressive behavior and risk stratification.

bioinformatics↗

CaCO3 Nanoparticles Delivering MicroRNA-200c Suppress Oral Squamous Cell Carcinoma

MicroRNA (miR)-200c suppresses the initiation and progression of oral squamous cell carcinoma (OSCC), the most prevalent head and neck cancer with high recurrence, metastasis, and mortality rates. However, miR-200c-based gene therapy to inhibit OSCC growth and metastasis has yet to be reported. To develop an miR-based gene therapy to improve the outcomes of OSCC treatment, this study investigates the feasibility of plasmid DNA encoding miR-200c delivered via non-viral CaCO3-based nanoparticles to inhibit OSCC tumor growth. CaCO3-based nanoparticles with various ratios of CaCO3 and protamine sulfate (PS) were utilized to transfect pDNA encoding miR-200c into OSCC cells and the efficiency of these nanoparticles was evaluated. The proliferation, migration, and associated oncogene production, as well as in vivo tumor growth for OSCC cells overexpressing miR-200c were also quantified. It was observed that, while CaCO3-based nanoparticles improve transfection efficiencies of pDNA miR-200c, the ratio of CaCO3 to PS significantly influences the transfection efficiency. Overexpression of miR-200c significantly reduced proliferation, migration, and oncogene expression of OSCC cells, as well as the tumor size of cell line-derived xenografts (CDX) in mice. In addition, a local administration of pDNA miR-200c using CaCO3 delivery significantly enhanced miR-200c transfection and suppressed tumor growth of CDX in mice. These results strongly indicate that the nanocomplexes of CaCO3/pDNA miR-200c may potentially be used to reduce oral cancer recurrence and metastasis and improve clinical outcomes in OSCC treatment. (227 words)

bioengineering↗