Browsing by Subject "cisplatin"

Now showing 1 - 4 of 4
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    Adjuvant Epidermal Growth Factor Receptor Inhibitors in Non-Small Cell Lung Cancer
    (Alphamed Press, 2015-09) Lourdes, Laura S.; Jalal, Shadia I.; Hanna, Nasser; Department of Medicine, IU School of Medicine
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    Clinical and Genome-wide Analysis of Cisplatin-induced Tinnitus Implicates Novel Ototoxic Mechanisms
    (American Association for Cancer Research, 2019-07-01) Charif, Omar El; Mapes, Brandon; Trendowski, Matthew R.; Wheeler, Heather E.; Wing, Claudia; Dinh, Paul C.; Frisina, Robert D.; Feldman, Darren R.; Hamilton, Robert J.; Vaughn, David J.; Fung, Chunkit; Kollmannsberger, Christian; Mushiroda, Taisei; Kubo, Michiaki; Gamazon, Eric R.; Cox, Nancy J.; Huddart, Robert; Ardeshir-Rouhani-Fard, Shirin; Monahan, Patrick; Fossa, Sophie D.; Einhorn, Lawrence H.; Travis, Lois B.; Dolan, M. Eileen; Medicine, School of Medicine
    Cisplatin, a commonly used chemotherapeutic, results in tinnitus, the phantom perception of sound. Our purpose was to identify the clinical and genetic determinants of tinnitus among testicular cancer survivors (TCS) following cisplatin-based chemotherapy. Experimental Design: TCS (n= 762) were dichotomized to cases (moderate/severe tinnitus; n=154) and controls (none; n=608). Logistic regression was used to evaluate associations with comorbidities and SNP dosages in GWAS following quality control and imputation (covariates: age, noise exposure, cisplatin dose, genetic principal components). Pathway over-representation tests and functional studies in mouse auditory cells were performed. Results: Cisplatin-induced tinnitus (CisIT) significantly associated with age at diagnosis (P=0.007) and cumulative cisplatin dose (P=0.007). CisIT prevalence was not significantly greater in 400 mg/m2-treated TCS compared to 300 (P=0.41), but doses >400 mg/m2 (median 580, range 402–828) increased risk by 2.61-fold (P<0.0001). CisIT cases had worse hearing at each frequency (0.25–12 kHz, P<0.0001), and reported more vertigo (OR=6.47; P<0.0001) and problems hearing in a crowd (OR=8.22; P<0.0001) than controls. Cases reported poorer health (P=0.0005) and greater psychotropic medication use (OR=2.4; P=0.003). GWAS suggested a variant near OTOS (rs7606353, P=2×10−6) and OTOS eQTLs were significantly enriched independently of that SNP (P=0.018). OTOS overexpression in HEI-OC1, a mouse auditory cell line, resulted in resistance to cisplatin-induced cytotoxicity. Pathway analysis implicated potassium ion transport (q=0.007). Conclusions: CisIT associated with several neuro-otological symptoms, increased use of psychotropic medication, and poorer health. OTOS, expressed in the cochlear lateral wall, was implicated as protective. Future studies should investigate otoprotective targets in supporting cochlear cells.
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    Identification of novel small molecule inhibitors of proteins required for genomic maintenance and stability
    (2010-06) Shuck, Sarah C.; Turchi, John J.; Kelley, Mark Richard, 1957-; Hurley, Thomas D., 1961-; Witzmann, F. A. (Frank A.)
    Targeting uncontrolled cell proliferation and resistance to DNA damaging chemotherapeutics using small molecule inhibitors of proteins involved in these pathways has significant potential in cancer treatment. Several proteins involved in genomic maintenance and stability have been implicated both in the development of cancer and the response to chemotherapeutic treatment. Replication Protein A, RPA, the eukaryotic single-strand DNA binding protein, is essential for genomic maintenance and stability via roles in both DNA replication and repair. Xeroderma Pigmentosum Group A, XPA, is required for nucleotide excision repair, the main pathway cells employ to repair bulky DNA adducts. Both of these proteins have been implicated in tumor progression and chemotherapeutic response. We have identified a novel small molecule that inhibits the in vitro and cellular ssDNA binding activity of RPA, prevents cell cycle progression, induces cytotoxicity and increases the efficacy of chemotherapeutic DNA damaging agents. These results provide new insight into the mechanism of RPA-ssDNA interactions in chromosome maintenance and stability. We have also identified small molecules that prevent the XPA-DNA interaction, which are being investigated for cellular and tumor activity. These results demonstrate the first molecularly targeted eukaryotic DNA binding inhibitors and reveal the utility of targeting a protein-DNA interaction as a therapeutic strategy for cancer treatment.
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    The Mechanotransduction Channel and Organic Cation Transporter Are Critical for Cisplatin Ototoxicity in Murine Hair Cells
    (Frontiers, 2022-02-10) Li , Jinan; Liu, Chang; Kaefer , Samuel; Youssef , Mariam; Zhao, Bo; Otolaryngology -- Head and Neck Surgery, School of Medicine
    Cisplatin is one of the most widely used chemotherapeutic drugs across the world. However, the serious ototoxic effects, leading to permanent hair cell death and hearing loss, significantly limit the utility of cisplatin. In zebrafish, the functional mechanotransduction channel is required for cisplatin ototoxicity. However, it is still unclear the extent to which the mechanotransduction channel is involved in cisplatin uptake and ototoxicity in mammalian hair cells. Herein, we show that genetically disrupting mechanotransduction in mouse partially protects hair cells from cisplatin-induced hair cell death. Using a fluorescent-dye conjugated cisplatin, we monitored cisplatin uptake in cochlear explants and found that functional mechanotransduction is required for the uptake of cisplatin in murine hair cells. In addition, cimetidine, an inhibitor of the organic cation transporter, also partially protects hair cells from cisplatin ototoxicity. Notably, the otoprotective effects of cimetidine do not require mechanotransduction. These findings suggest that both the mechanotransduction channel and the organic cation transporter are critical for cisplatin ototoxicity in murine hair cells.