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Öğe Atezolizumab in patients with metastatic urothelial carcinoma who have progressed after first-line chemotherapy: Results of real-life experiences(Elsevier, 2021) Tural, Deniz; Ölmez, Ömer Fatih; Sümbül, Ahmet Taner; Artaç, Mehmet; Özhan, Nail; Akar, Emre; Çakar, Burcu; Köstek, Osman; Ekenel, Meltem; Erman, Mustafa; Coşkun, Hasan Şenol; Selçukbiricik, Fatih; Keskin, Özge; Türköz, Fatma Paksoy; Oruç, Kerem; Bayram, Selami; Yılmaz, Uğur; Bilgetekin, İrem; Yıldız, Birol; Şendur, Mehmet Ali Nahit; Paksoy, Nail; Dirican, Ahmet; Erdem, Dilek; Selam, Meltem; Tanrıverdi, Özgür; Paydaş, Semra; Urakçı, Zuhat; Atağ, Elif; Güncan, Sabri; Ürün, Yüksel; Alkan, Ali; Kaya, Ali Osman; Özyükseler, Deniz Tataroğlu; Taşkaynatan, Halil; Yıldırım, Mustafa; Sönmez, Müge; Başoğlu, Tuğba; Gündüz, Şeyda; Kılıçkap, SaadettinBackground: Atezolizumab (ATZ) has demonstrated antitumor activity and manageable safety in previous studies in patients with locally advanced or metastatic platinum resistant urothelial carcinoma. Objective: To compare the real-life experience and data of clinical trials on ATZ treatment in metastatic urothelial carcinoma. Design, setting, and participants: Patients with urothelial cancer treated with ATZ after progression on first-line chemotherapy from an expanded access program were retrospectively studied. Data of patients were obtained from their files and hospital records. Safety was evaluated for patients treated with at least one cycle of ATZ. Outcome measurements and statistical analysis: The primary endpoint was objective response rate (ORR). The secondary endpoints are overall survival (OS), progression-free survival (PFS), duration of response, and safety profile of patients. Kaplan-Meier methods were used to calculate median follow-up and estimate PFS and OS. Results and limitations: Data of 115 enrolled patients were analyzed. Most of the patients (92.3%, n = 106) had received chemotherapy regimen only once prior to ATZ. The median follow-up duration was 23.5 mo. The complete response rate, partial response rate, and ORR were 8.7% (n = 10), 20.0% (n = 23), and 28.7% (n = 33), respectively. The median duration of response was 20.4 mo (95% confidence interval [CI], 6.47-28.8). Of the 33 patients who responded to treatment, 60% (n = 20) had an ongoing response at the time of the analysis. PFS and OS with ATZ were 3.8 mo (95% CI, 2.25-5.49) and 9.8 mo (95% CI, 6.7-12.9), respectively. All-cause and any-grade adverse events were observed in 113 (98%) patients. Of the patients, 64% experienced a treatment-related adverse event of any grade and 24 (21.2%) had a grade 3-4 treatment-related adverse event. Limitations of the study included its retrospective design, and determination of treat-ment response based on clinical notes and local radiographic studies. Conclusions: In these real-life data, ATZ was effective and well tolerated in patients with metastatic urothelial carcinoma who have progressed with platinum-based first-line chemotherapy. ATZ is an effective and tolerable treatment for patients with locally advanced or metastatic platinum-resistant urothelial carcinoma in our study, similar to previously reported trials. Patient summary: Atezolizumab is effective and well-tolerated in patients with meta-static urothelial cancer who progressed with first-line chemotherapy, consistent with the outcomes of the previous clinical trials in this setting. (c) 2020 European Association of Urology. Published by Elsevier B.V. All rights reserved.Öğe A potential treatment of nonalcoholic fatty liver disease with SIRT1 activators(Romanian Society of Gastroenterology, 2014) Çolak, Yaşar; Yeşil, Atakan; Mutlu, Hasan Hüseyin; Çaklılı, Özge Telci; Ulaşoğlu, Celal; Takir, Mümtaz; Köstek, Osman; Şenateş, EbubekirSirtuins (SIRTs) are members of the silent information regulator-2 family and act as nicotinamide adenine dinucleotide (NAD+)-dependent histone/protein deacetylases. The de-acetylation of proteins and histones results in an up-or down-regulation of gene transcription and protein function. In recent years, the regulatory action of the deacetylation activity of SIRT1 has been shown to have a positive impact on the pathophysiological mechanisms of nonalcoholic fatty liver disease (NAFLD). Among the effects of SIRT1 are: its healing activity on insulin sensitivity, thereby ameliorating glycemic regulation; its mimetic activity on calorie restriction; its antihyperlipidemic activity on lipid homeostasis via the liver, adipose tissues and skeletal muscles; its antiinflammatory activities; its protective effects against cardiovascular events and endothelial dysfunction; its positive influence on autophagy, apoptosis and cancer; and finally, its anti-aging activity. The current approach for the treatment of NAFLD involves the treatment of etiological factors and recommendation of life-style changes including more physical activity and a low-calorie diet. However, there are no specific medical treatments for NAFLD. The therapeutic potential of SIRT1 activity in the treatment of NAFLD discovered in humans has been presented in this article. In this review, the potential effects of SIRT1 activation on NAFLD-related pathophysiological mechanisms and on the treatment of NAFLD are discussed.Öğe The prognostic factors in patients with advanced hepatocellular carcinoma: impact of treatment sequencing(Taylor and Francis Ltd., 2024) Köstek, Osman; Demirel, Ahmet; Hacıoğlu, Muhammet Bekir; Taştekin, Didem; Karabulut, Senem; Gündogdu, Abidin; Sever, Nadiye; Kaplan, Muhammet Ali; 0000-0002-1901-5603; 0000-0003-0882-0524The prognosis of patients with advanced HCC can vary widely depending on factors such as the stage of the cancer, the patient’s overall health, and treatment regimens. This study aimed to investigate survival outcomes and associated factors in patients with hepatocellular carcinoma (HCC). In this retrospective study, data from 23 medical oncology clinics were analyzed. Progression-free survival (PFS) and overall survival (OS) values were estimated using the Kaplan–Meier method. Prognostic factors associated with survival which were identified in univariate analysis were subsequently evaluated in a multivariate Cox-regression survival analysis was conducted using the backward stepwise (Conditional LR) method to determine the independent predictors of PFS and OS. Of 280 patients, 131 received chemotherapy and 142 received sorafenib, 6 received atezolizumab plus bevacizumab and 1 received nivolumab for first-line setting. The median follow-up time was 30.4 (95%CI 27.1–33.6) months. For-first line, median PFS was 3.1 (95%CI2.7–3.5) months, and it was significantly longer in patients who received sorafenib or atezolizumab-bevacizumab or nivolumab (PFS 5.8 (95%CI 4.2–7.5) than in those received chemotherapy (PFS 2.1 (95%CI 1.9–2.3) in the first-line setting (p < 0.001). Multivariate analysis revealed that male gender (HR: 2.75, 95% CI: 1.53–4.94, p = 0.01), poor ECOG performance score (HR: 1.88, 95% CI: 1.10–3.21, p = 0.02), higher baseline AFP level (HR: 2.38, 95% CI: 1.54–3.67, p < 0.001) and upfront sorafenib treatment (HR,0.38; 95% CI: 0.23–0.62, p < 0.001) were significantly associated with shorter PFS. The median OS was 13.2 (95%CI 11.1–15.2) months. It was significantly longer in patients who received sorafenib or atezolizumab-bevacizumab or nivolumab in the first-line setting followed by TKIs (sorafenib or regorafenib, OS 18.6 (95%CI 13.8–23.5)) compared to those who received chemotherapy (OS 10.3 (95%CI 6.6–14.1)) in the first-line setting. The multivariate analysis revealed that upfront chemotherapy treatment approach, male gender (HR: 1.77, 95% CI: 1.07–2.94, p = 0.02), poor ECOG performance score (HR: 1.96, 95% CI: 1.24–3.09, p = 0.004) and Child-Pugh score, presence of extrahepatic disease (HR: 1.54, 95% CI: 1.09–2.18, p = 0.01), and higher baseline AFP value (HR: 1.50, 95% CI: 1.03–2.19, p = 0.03) were significantly associated with poor prognosis. Additionally, regarding of treatment sequence, upfront sorafenib followed by regorafenib showed a significantly lower risk of mortality (HR: 0.40, 95% CI: 0.25–0.66, p < 0.001). Sorafenib followed by regorafenib treatment was associated with a significantly lower risk of mortality rather than upfront sorafenib followed by BSC group or upfront chemotherapy followed by TKIs. These findings underscore the importance of the optimal treatment sequences to improve survival in patients with advanced HCC.Öğe Sunitinib or pazopanib: Is there any difference between tyrosine kinase inhibitors in the pre-nivolumab setting in metastatic renal cell carcinoma?(Cureus Inc., 2020) Uçar, Gökhan; Açıkgöz, Yusuf; Ergun, Yakup; Bal, Öznur; Yılmaz, Mesut; Karakaya, Serdar; Akdeniz, Nadiye; Köstek, Osman; Isak, Özlem Aydın; Şener, Görkem Yazıcı; Dirikoç, Merve; Esen, Selin Aktürk; Doğan, Mutlu; Uncu, DoğanIntroduction Treatment options for metastatic renal cell carcinoma disease have been improved in recent years. However, there is still no optimal treatment sequence or combination for metastatic disease. We aimed to investigate whether patients differed in terms of disease outcomes regarding pre-nivolumab tyrosine kinase inhibitors (TKIs). Material and methods The analysis of patients was performed after all cohorts were sub-grouped into two groups according to pre-nivolumab TKIs as following the sunitinib arm and the pazopanib arm. Result A total of 75 patients were included in this study. The median follow-up time was eight months for all cohorts. The objective response rate was statistically significantly higher in the pazopanib arm as compared to the sunitinib arm (56% vs 30%, p=0.02). Progression-free survival was significantly higher in pazopanib than sunitinib (10.3 months vs 5.3 months, p=0.02). Multivariate analysis revealed that pazopanib treatment was associated with better progression-free survival (HR: 0.44, 95 CI; 0.22-0.91, p=0.02). While the median overall survival for patients who had received sunitinib was 11.0 months, it has not been reached the median in the pazopanib arm (11.0 months vs NR, p=0.051). Discussion We demonstrated significantly better progression-free survival and a higher objective response rate with nivolumab treatment in patients who had received pazopanib as compared with patients who received sunitinib in the pre-nivolumab period.
