Browsing by Author "Shao, Minghai"

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    Benefits of combination therapy with immune checkpoint inhibitors and predictive role of tumour mutation burden in hepatocellular carcinoma: A systematic review and meta-analysis
    (Elsevier, 2022-11) Zheng, Jiaxi; Shao, Minghai; Yang , Weifang; Ren , Justin; Chen, Xiaofeng; Yang, Haihua; Radiation Oncology, School of Medicine
    Objectives To investigate the clinical benefits of combination therapy with immune checkpoint inhibitors (ICIs) and best combination regimen for people with advanced hepatocellular carcinoma (HCC) and to explore the predictive performance of tumour mutation burden (TMB). Methods We conducted a systematic literature search to identify clinical trials. Meta-analysis and subgroup analyses were performed to estimate the benefits of combination regimens with PD-1/PD-L1 inhibitors for patients with advanced HCC and compare the effectiveness of PD-1/PD-L1 inhibitors and sorafenib as first-line therapy. Individualized analysis and Kaplan-Meier were used to assess the prognostic value of TMB. Results A total of 29 studies with 5396 patients were included. ICIs’ combination therapy had higher ORR (26 % vs 15 %) and DCR (73 % vs 55 %), longer PFS (5.5 vs 3.1 months) and OS (15.9 vs 12.6 months) compared to monotherapy. Anti-PD-1/PD-L1 agents provided improved ORR, DCR, PFS and OS compared to sorafenib. The overall ORs of ORR and DCR in subgroup analysis were 3.49 (95 % CI 2.36–5.17, p < 0.01) and 1.60 (95 % CI 1.15–2.21, p < 0.01). The overall HRs of PFS and OS were 0.68 (95 % CI 0.48–0.96, p = 0.03) and 0.73 (95 % CI 0.62–0.85, p < 0.01). PD-1/PD-L1 inhibitors plus anti-VEGF agents had an advantage in DCR (0.80 vs 0.48, meta-regression = − 0.32, P < 0.001), but an equal ORR (0.29 vs 0.26) compared to dual immune checkpoint inhibitors. The total OS in Dua-ICIs were 16.5 months (95 % CI 14.2–18.7), yet not reached in the major studies of ICI plus anti-VEGF regimen. In individualized analysis, the 1-year OS was superior for patients who had high-TMB (>10, mutations/Mb) than moderate-TMB (1–10, mutations/Mb; 28 % vs 15 %, P = 0.025). Conclusion Immune checkpoint inhibitors’ combination therapy improved clinical outcomes in the management of advanced hepatocellular carcinoma. However, the overall objective response rate still did not exceed 30%. PD-1/PD-L1 inhibitors plus anti-angiogenic agents and dual immunotherapy provided significantly increased survival over sorafenib, which also pose new challenges for future research, and more appropriate and guided control regimens are required. Also, TMB may be a promising prognostic biomarker for immunotherapy in HCC. However, the validation of prospective and large sample studies is needed.
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    Calcium/Calmodulin-Dependent Protein Kinase II Regulation of IKs during Sustained Beta-Adrenergic Receptor Stimulation
    (Elsevier, 2018) Shugg, Tyler; Johnson, Derrick E.; Shao, Minghai; Lai, Xianyin; Witzmann, Frank; Cummins, Theodore R.; Rubart-Von der Lohe, Michael; Hudmon, Andy; Overholser, Brian R.; Biochemistry and Molecular Biology, School of Medicine
    Background Sustained β-adrenergic receptor (β-AR) stimulation causes pathophysiological changes during heart failure (HF), including inhibition of the slow component of the delayed rectifier potassium current (IKs). Aberrant calcium handling, including increased activation of calcium/calmodulin-dependent protein kinase II (CaMKII), contributes to arrhythmia development during HF. Objective The purpose of this study was to investigate CaMKII regulation of KCNQ1 (pore-forming subunit of IKs) during sustained β-AR stimulation and associated functional implications on IKs. Methods KCNQ1 phosphorylation was assessed using LCMS/MS after sustained β-AR stimulation with isoproterenol (ISO). Peptide fragments corresponding to KCNQ1 residues were synthesized to identify CaMKII phosphorylation at the identified sites. Dephosphorylated (alanine) and phosphorylated (aspartic acid) mimics were introduced at identified residues. Whole-cell, voltage-clamp experiments were performed in human endothelial kidney 293 cells coexpressing wild-type or mutant KCNQ1 and KCNE1 (auxiliary subunit) during ISO treatment or lentiviral δCaMKII overexpression. Results Novel KCNQ1 carboxy-terminal sites were identified with enhanced phosphorylation during sustained β-AR stimulation at T482 and S484. S484 peptides demonstrated the strongest δCaMKII phosphorylation. Sustained β-AR stimulation reduced IKs activation (P = .02 vs control) similar to the phosphorylated mimic (P = .62 vs sustained β-AR). Individual phosphorylated mimics at S484 (P = .04) but not at T482 (P = .17) reduced IKs function. Treatment with CN21 (CaMKII inhibitor) reversed the reductions in IKs vs CN21-Alanine control (P < .01). δCaMKII overexpression reduced IKs similar to ISO treatment in wild type (P < .01) but not in the dephosphorylated S484 mimic (P = .99). Conclusion CaMKII regulates KCNQ1 at S484 during sustained β-AR stimulation to inhibit IKs. The ability of CaMKII to inhibit IKs may contribute to arrhythmogenicity during HF.
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    MicroRNA 362-3p Reduces hERG-related Current and Inhibits Breast Cancer Cells Proliferation
    (International Institute of Anticancer Research, 2019-12) Assiri, Abdullah A.; Mourad, Noha; Shao, Minghai; Kiel, Patrick; Liu, Wanqing; Skaar, Todd C.; Overholser, Brian R.; Pharmacology and Toxicology, School of Medicine
    Background/Aim: hERG potassium channels enhance tumor invasiveness and breast cancer proliferation. MicroRNA (miRNA) dysregulation during cancer controls gene regulation. The objective of this study was to identify miRNAs that regulate hERG expression in breast cancer. Materials and Methods: Putative miRNAs targeting hERG were identified by bioinformatic approaches and screened using a 3’UTR luciferase assay. Functional assessments of endogenous hERG regulation were made using whole-cell electrophysiology, proliferation assays, and cell-cycle analyses following miRNA, hERG siRNA, or control transfection. Results: miR-362-3p targeted hERG 3’UTR and was associated with higher survival rates in patients with breast cancer (HR=0.39, 95%CI=0.18-0.82). Enhanced miR-362-3p expression reduced hERG expression, peak current, and cell proliferation in cultured breast cancer cells (p<0.05). Conclusion: miR-362-3p mediates the transcriptional regulation of hERG and is associated with survival in breast cancer. The potential for miR-362-3p to serve as a biomarker and inform therapeutic strategies warrants further investigation.
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    Targeting the insulin growth factor and the vascular endothelial growth factor pathways in ovarian cancer
    (American Association for Cancer Research, 2012-07) Shao, Minghai; Hollar, Stacy; Chambliss, Daphne; Schmitt, Jordan; Emerson, Robert; Chelladurai, Bhadrani; Perkins, Susan; Ivan, Mircea; Matei, Daniela; Department of Medicine, IU School of Medicine
    Antiangiogenic therapy is emerging as a highly promising strategy for the treatment of ovarian cancer, but the clinical benefits are usually transitory. The purpose of this study was to identify and target alternative angiogenic pathways that are upregulated in ovarian xenografts during treatment with bevacizumab. For this, angiogenesis-focused gene expression arrays were used to measure gene expression levels in SKOV3 and A2780 serous ovarian xenografts treated with bevacizumab or control. Reverse transcription-PCR was used for results validation. The insulin growth factor 1 (IGF-1) was found upregulated in tumor and stromal cells in the two ovarian xenograft models treated with bevacizumab. Cixutumumab was used to block IGF-1 signaling in vivo. Dual anti-VEGF and IGF blockade with bevacizumab and cixutumumab resulted in increased inhibition of tumor growth. Immunohistochemistry measured multivessel density, Akt activation, and cell proliferation, whereas terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay measured apoptosis in ovarian cancer xenografts. Bevacizumab and cixutumumab combination increased tumor cell apoptosis in vivo compared with therapy targeting either individual pathway. The combination blocked angiogenesis and cell proliferation but not more significantly than each antibody alone. In summary, IGF-1 activation represents an important mechanism of adaptive escape during anti-VEGF therapy in ovarian cancer. This study provides the rationale for designing bevacizumab-based combination regimens to enhance antitumor activity.