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Browsing by Author "Elbanna, May"
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Item Anti-tumor activity and mechanistic characterization of APE1/Ref-1 inhibitors in bladder cancer(American Association for Cancer Research, 2019-08-14) Fishel, Melissa L.; Xia, Hanyu; McGeown, Jack; McIlwain, David W.; Elbanna, May; Craft, Ariel A.; Kaimakliotis, Hristos Z.; Sandusky, George E.; Zhang, Chi; Pili, Roberto; Kelley, Mark R.; Jerde, Travis J.; Pharmacology and Toxicology, School of MedicineBladder cancer is the ninth most common cause of cancer-related deaths worldwide. Although cisplatin is used routinely in treating bladder cancer, refractory disease remains lethal for many patients. The recent addition of immunotherapy has improved patient outcomes; however, a large cohort of patients does not respond to these treatments. Therefore, identification of innovative molecular targets for bladder cancer is crucial. Apurinic/apyrimidinic endonuclease 1/redox factor-1 (APE1/Ref-1) is a multifunctional protein involved in both DNA repair and activation of transcription factors through reduction-oxidation (redox) regulation. High APE1/Ref-1 expression is associated with shorter patient survival time in many cancer types. In this study, we found high APE1/Ref-1 expression in human bladder cancer tissue relative to benign urothelium. Inhibition of APE1/Ref-1 redox signaling using APE1/Ref-1-specific inhibitors attenuates bladder cancer cell proliferation in monolayer, in three-dimensional cultures, and in vivo. This inhibition corresponds with an increase in apoptosis and decreased transcriptional activity of NF-κB and STAT3, transcription factors known to be regulated by APE1/Ref-1, resulting in decreased expression of downstream effectors survivin and Cyclin D1 in vitro and in vivo. We also demonstrate that in vitro treatment of bladder cancer cells with APE1/Ref-1 redox inhibitors in combination with standard-of-care chemotherapy cisplatin is more effective than cisplatin alone at inhibiting cell proliferation. Collectively, our data demonstrate that APE1/Ref-1 is a viable drug target for the treatment of bladder cancer, provide a mechanism of APE1/Ref-1 action in bladder cancer cells, and support the use of novel redox-selective APE1/Ref-1 inhibitors in clinical studies. SIGNIFICANCE: This work identifies a critical mechanism for APE1/Ref-1 in bladder cancer growth and provides compelling preclinical data using selective redox activity inhibitors of APE1/Ref-1 in vitro and in vivo.Item Clinical and Preclinical Outcomes of Combining Targeted Therapy With Radiotherapy(Frontiers Media, 2021-10-18) Elbanna, May; Chowdhury, Nayela N.; Rhome, Ryan; Fishel, Melissa L.; Radiation Oncology, School of MedicineIn the era of precision medicine, radiation medicine is currently focused on the precise delivery of highly conformal radiation treatments. However, the tremendous developments in targeted therapy are yet to fulfill their full promise and arguably have the potential to dramatically enhance the radiation therapeutic ratio. The increased ability to molecularly profile tumors both at diagnosis and at relapse and the co-incident progress in the field of radiogenomics could potentially pave the way for a more personalized approach to radiation treatment in contrast to the current ''one size fits all'' paradigm. Few clinical trials to date have shown an improved clinical outcome when combining targeted agents with radiation therapy, however, most have failed to show benefit, which is arguably due to limited preclinical data. Several key molecular pathways could theoretically enhance therapeutic effect of radiation when rationally targeted either by directly enhancing tumor cell kill or indirectly through the abscopal effect of radiation when combined with novel immunotherapies. The timing of combining molecular targeted therapy with radiation is also important to determine and could greatly affect the outcome depending on which pathway is being inhibited.Item EZH2 modifies sunitinib resistance in renal cell carcinoma by kinome reprogramming(Cancer Research, 2017-12-01) Adelaiye-Ogala, Remi; Budka, Justin; Damayanti, Nur P.; Arrington, Justine; Ferris, Mary; Hsu, Chuan-Chih; Chintala, Sreenivasulu; Orillion, Ashley; Miles, Kiersten Marie; Shen, Li; Elbanna, May; Ciamporcero, Eric; Arisa, Sreevani; Pettazzoni, Piergiorgio; Draetta, Giulio F.; Seshadri, Mukund; Hancock, Bradley; Radovich, Milan; Kota, Janaiah; Buck, Michael; Keilhack, Heike; McCarthy, Brian P.; Persohn, Scott A.; Territo, Paul R.; Zang, Yong; Irudayaraj, Joseph; Tao, W. Andy; Hollenhorst, Peter; Pili, RobertoAcquired and intrinsic resistance to receptor tyrosine kinase inhibitors (RTKi) represent a major hurdle in improving the management of clear cell renal cell carcinoma (ccRCC). Recent reports suggest that drug resistance is driven by tumor adaptation via epigenetic mechanisms that activate alternative survival pathways. The histone methyl transferase EZH2 is frequently altered in many cancers including ccRCC. To evaluate its role in ccRCC resistance to RTKi, we established and characterized a spontaneously metastatic, patient-derived xenograft (PDX) model that is intrinsically resistant to the RTKI sunitinib but not to the VEGF therapeutic antibody bevacizumab. Sunitinib maintained its anti-angiogenic and anti-metastatic activity but lost its direct anti-tumor effects due to kinome reprogramming, which resulted in suppression of pro- apoptotic and cell cycle regulatory target genes. Modulating EZH2 expression or activity suppressed phosphorylation of certain RTK, restoring the anti-tumor effects of sunitnib in models of acquired or intrinsically resistant ccRCC. Overall, our results highlight EZH2 as a rational target for therapeutic intervention in sunitinib-resistant ccRCC as well as a predictive marker for RTKi response in this disease.Item Impact of Lung Parenchymal-Only Failure on Overall Survival in Early-Stage Lung Cancer Patients Treated With Stereotactic Ablative Radiotherapy(Elsevier, 2021) Elbanna, May; Shiue, Kevin; Edwards, Donna; Cerra-Franco, Alberto; Agrawal, Namita; Hinton, Jason; Mereniuk, Todd; Huang, Christina; Ryan, Joshua L.; Smith, Jessica; Aaron, Vasantha D.; Burney, Heather; Zang, Yong; Holmes, Jordan; Langer, Mark; Zellars, Richard; Lautenschlaeger, Tim; Radiation Oncology, School of MedicineIntroduction: The impact of lung parenchymal-only failure on patient survival after stereotactic ablative body radiotherapy (SABR) for early-stage non-small-cell lung cancer (NSCLC) remains unclear. Patients and methods: The study population included 481 patients with early-stage NSCLC who were treated with 3- to 5-fraction SABR between 2000 and 2016. The primary study objective was to assess the impact of out-of-field lung parenchymal-only failure (OLPF) on overall survival (OS). Results: At a median follow-up of 5.9 years, the median OS was 2.7 years for all patients. Patients with OLPF did not have a significantly different OS compared to patients without failure (P = .0952, median OS 4.1 years with failure vs. 2.6 years never failure). Analysis in a 1:1 propensity score-matched cohort for Karnofsky performance status, comorbidity score, and smoking status showed no differences in OS between patients without failure and those with OLPF (P = .8). In subgroup analyses exploring the impact of time of failure on OS, patients with OLPF 6 months or more after diagnosis did not have significantly different OS compared to those without failure, when accounting for immortal time bias (P = .3, median OS 4.3 years vs. 3.5 years never failure). Only 7 patients in our data set experienced failure within 6 months of treatment, of which only 4 were confirmed to be true failures; therefore, limited data are available in our cohort on the impact of OLPF for ≤ 6 months on OS. Conclusion: OLPF after SABR for early-stage NSCLC does not appear to adversely affect OS, especially if occurring at least 6 months after SABR. More studies are needed to understand if OLPF within 6 months of SABR is associated with adverse OS. These data are useful when discussing prognosis of lung parenchymal failures after initial SABR.Item Therapeutic Targeting of TFE3/IRS-1/PI3K/mTOR Axis in Translocation Renal Cell Carcinoma(American Association for Cancer Research, 2018-12) Damayanti, Nur P.; Budka, Justin A.; Khella, Heba W. Z.; Ferris, Mary W.; Ku, Sheng Yu; Kauffman, Eric; Wood, Anthony C.; Ahmed, Khunsha; Chintala, Venkata Nithinsai; Adelaiye-Ogala, Remi; Elbanna, May; Orillion, Ashley; Chintala, Sreenivasulu; Kao, Chinghai; Linehan, W. Marston; Yousef, George M.; Hollenhorst, Peter C.; Pili, Roberto; Medicine, School of MedicinePurpose: Translocation renal cell carcinoma (tRCC) represents a rare subtype of kidney cancer associated with various TFE3, TFEB, or MITF gene fusions that are not responsive to standard treatments for RCC. Therefore, the identification of new therapeutic targets represents an unmet need for this disease. Experimental Design: We have established and characterized a tRCC patient-derived xenograft, RP-R07, as a novel preclinical model for drug development by using next-generation sequencing and bioinformatics analysis. We then assessed the therapeutic potential of inhibiting the identified pathway using in vitro and in vivo models. Results: The presence of a SFPQ-TFE3 fusion [t(X;1) (p11.2; p34)] with chromosomal break-points was identified by RNA-seq and validated by RT-PCR. TFE3 chromatin immunoprecipitation followed by deep sequencing analysis indicated a strong enrichment for the PI3K/AKT/mTOR pathway. Consistently, miRNA microarray analysis also identified PI3K/AKT/mTOR as a highly enriched pathway in RP-R07. Upregulation of PI3/AKT/mTOR pathway in additional TFE3–tRCC models was confirmed by significantly higher expression of phospho-S6 (P < 0.0001) and phospho-4EBP1 (P < 0.0001) in established tRCC cell lines compared with clear cell RCC cells. Simultaneous vertical targeting of both PI3K/AKT and mTOR axis provided a greater antiproliferative effect both in vitro (P < 0.0001) and in vivo (P < 0.01) compared with single-node inhibition. Knockdown of TFE3 in RP-R07 resulted in decreased expression of IRS-1 and inhibited cell proliferation. Conclusions: These results identify TFE3/IRS-1/PI3K/AKT/mTOR as a potential dysregulated pathway in TFE3–tRCC, and suggest a therapeutic potential of vertical inhibition of this axis by using a dual PI3K/mTOR inhibitor for patients with TFE3–tRCC.