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Alena Novakova-Jiresova,1 Katerina Kopeckova,2 Ludmila Boublikova,1 Renata Chloupkova,3 Bohuslav Melichar,4 Lubos Petruzelka,5 Jindrich Finek,6 Ondrej Fiala,6,7 Peter Grell,8 Stanislav Batko,2 Zdenek Linke,2 Igor Kiss,8 Jana Prausova,2 Tomas Buchler1 1Department of Oncology, First Faculty of Medicine and Thomayer Hospital, Charles University, Prague, Czech Republic; 2Department of Oncology, University Hospital in Motol, Charles University, Prague, Czech Republic; 3Institute of Biostatistics and Analysis, Faculty of Medicine, Masaryk University, Brno, Czech Republic; 4Department of Oncology, Palacky University Medical and Teaching Hospital, Olomouc, Czech Republic; 5Department of Oncology, General Faculty Hospital, Charles University, Prague, Czech Republic; 6Department of Oncology and Radiotherapy, Medical School and University Hospital in Pilsen, Charles University, Pilsen, Czech Republic; 7Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Pilsen, Czech Republic; 8Department of Comprehensive Cancer Care, Masaryk Memorial Cancer Institute, Brno, Czech RepublicCorrespondence: Tomas BuchlerDepartment of Oncology, First Faculty of Medicine and Thomayer Hospital, Charles University, Videnska 800, Prague 140 59, Czech RepublicTel +420-261-082-637Fax +420-261-082-522Email tomas.buchler@ftn.czPurpose: Regorafenib is an oral multikinase inhibitor approved for the therapy of previously treated metastatic colorectal carcinoma (mCRC). The aim of the present study was to analyze the outcomes of treatment with regorafenib in real-world clinical practice based on data from a national registry.Methods: The CORECT registry, the Czech non-interventional database of patients with mCRC treated with targeted agents, searched for patients with metastatic CRC treated with regorafenib. In total, 555 evaluable patients were identified.Results: The median age at diagnosis was 61.7 years. All patients had disease progression on or after previous systemic treatment. Most patients were treated with an initial dose of 160 mg daily (n = 463; 83.6%). The median duration of treatment was 2.7 months (range 0.0– 23.4 months). By the data cut-off date, 472 patients (85%) had completed treatment with regorafenib and were evaluable for treatment response evaluation. Partial response was reported in 13 patients (2.8%) and disease stabilization in 130 patients (27.5%). Median progression-free survival (PFS) and overall survival (OS) were 3.5 months (95% confidence interval [CI] 3.2– 3.7 months) and 9.3 months (95% CI 8.3– 10.3 months), respectively. The 6-month OS rate was 67.7% (95% CI 63.4– 72.1%). Multivariable analysis showed that female gender, longer interval from diagnosis of metastatic disease, M0 stage at diagnosis, and Eastern Cooperative Oncology Group performance status (ECOG PS) 0 were associated with longer PFS, while higher body-mass index (BMI), longer interval from diagnosis of metastatic disease, and ECOG PS of 0 were associated with longer OS.Conclusion: OS of patients treated with regorafenib in the real-world clinical practice in this cohort exceeded that reported in randomized trials. Regorafenib is a safe and active treatment option for a subgroup of patients with mCRC who are progressing after other systemic therapies and maintain good performance status.Keywords: colorectal cancer, regorafenib, registry, survival, outcome analysis

Tomas Buchler,1 Renata Chloupkova,2 Alexandr Poprach,3 Ondrej Fiala,4,5 Igor Kiss,3 Katerina Kopeckova,6 Ladislav Dusek,2 Veronika Veskrnova,1 Lubomir Slavicek,7 Milan Kohoutek,8 Jindrich Finek,4 Marek Svoboda,3 Lubos Petruzelka,9 Bohuslav Melichar10 1Department of Oncology, First Faculty of Medicine, Charles University and Thomayer University Hospital, 140 59 Prague, Czech Republic; 2Institute of Biostatistics and Analyses, Faculty of Medicine, Masaryk University, 625 00 Brno, Czech Republic; 3Department of Comprehensive Cancer Care and Faculty of Medicine, Masaryk Memorial Cancer Institute and Masaryk University, Brno 656 53, Czech Republic; 4Department of Oncology, University Hospital, 304 60 Pilsen, Czech Republic; 5Biomedical Center, Faculty of Medicine in Pilsen, Charles University, Prague, Czech Republic; 6Department of Oncology, Motol University Hospital and Second Faculty of Medicine, Charles University, 150 00 Prague, Czech Republic; 7Department of Oncology, Jihlava Hospital Comprehensive Cancer Centre, Jihlava, Czech Republic; 8Department of Oncology, T Bata Hospital and Comprehensive Cancer Centre, Zlin, Czech Republic; 9Department of Oncology, General University Hospital and Charles University First Faculty of Medicine, 128 08 Prague, Czech Republic; 10Department of Oncology, Palacky University Medical School and Teaching Hospital, 775 20 Olomouc, Czech Republic Purpose: Although inhibitors of vascular endothelial growth factor and inhibitors of epidermal growth factor receptor (EGFRi) are commonly used for the treatment of metastatic colorectal cancer (mCRC), the optimal sequencing of these agents is currently unclear. Methods: A national registry of targeted therapies was used to analyze baseline ­characteristics and outcomes of patients with mCRC and wild-type KRAS exon 2 status who received ­bevacizumab and EGFRi (cetuximab or panitumumab) as a part of first- and second-line ­treatment in either sequence. Results: The cohort included 490 patients (181 patients treated with first-line EGFRi and second-line bevacizumab and 309 patients treated with first-line bevacizumab and second-line EGFRi). Median overall survival (OS) from the initiation on first-line therapy was similar for patients treated with either sequence, reaching 31.8 (95% CI 27.5–36.1) vs 31.4 months (95% CI 27.8–35.0) for EGFRi → bevacizumab vs bevacizumab → EGFRi cohort, respectively. Time from first-line initiation to progression on the second-line therapy [progression-free survival (PFS)] was 21.1 (95% CI 19.3–23.0) vs 19.3 months (95% CI 17.3–21.3) for bevacizumab → EGFRi vs EGFRi → bevacizumab cohort, respectively (P=0.016). Conclusion: This retrospective analysis of real-world data of patients with wild-type KRAS exon 2 mCRC showed no differences in OS between cohorts treated with bevacizumab → EGFRi vs the reverse sequence while combined PFS favored the bevacizumab → EGFRi sequence. Keywords: colorectal carcinoma, bevacizumab, panitumumab, cetuximab, sequence

High-grade serous ovarian carcinoma (HGSC) is the most common subtype of ovarian cancer and is among the most fatal gynecological malignancies worldwide, due to late diagnosis at advanced stages and frequent therapy resistance. In 47 HGSC patients, we assessed somatic and germline genetic variability of a custom panel of 144 known or suspected HGSC-related genes by high-coverage targeted DNA sequencing to identify the genetic determinants associated with resistance to platinum-based therapy. In the germline, the most mutated genes were DNAH14 (17%), RAD51B (17%), CFTR (13%), BRCA1 (11%), and RAD51 (11%). Somatically, the most mutated gene was TP53 (98%), followed by CSMD1/2/3 (19/19/36%), and CFTR (23%). Results were compared with those from whole exome sequencing of a similar set of 35 HGSC patients. Somatic variants in TP53 were also validated using GENIE data of 1287 HGSC samples. Our approach showed increased prevalence of high impact somatic and germline mutations, especially those affecting splice sites of TP53, compared to validation datasets. Furthermore, nonsense TP53 somatic mutations were negatively associated with patient survival. Elevated TP53 transcript levels were associated with platinum resistance and presence of TP53 missense mutations, while decreased TP53 levels were found in tumors carrying mutations with predicted high impact, which was confirmed in The Cancer Genome Atlas data (n = 260). Targeted DNA sequencing of TP53 combined with transcript quantification may contribute to the concept of precision oncology of HGSC. Future studies should explore targeting the p53 pathway based on specific mutation types and co-analyze the expression and mutational profiles of other key cancer genes., (© 2024 The Authors. International Journal of Cancer published by John Wiley & Sons Ltd on behalf of UICC.)

Objectives: This article estimates the cost-effectiveness of adding pertuzumab to the combination of trastuzumab and docetaxel within the first-line treatment for metastatic breast cancer with the amplification of HER2+., Methods: Data from Czech clinical practice recorded in the BREAST register are used. A semi-Markov model with states derived based on the treatment phases (first-line medication, no medication, next-line medication, death) is defined to estimate costs from the healthcare payers' perspective. The benefits are estimated as patient survival until death. The Kaplan-Meier estimates are supplemented by the Cox proportional hazard and the accelerated failure time models to control for patient characteristics. Health-related quality-of-life indicators are derived from relevant literature., Results: Based on the used data, adding pertuzumab does not result in statistically significantly longer survival while inducing higher treatment costs (€163 360 compared with €90 112 per patient in 2018 prices). Statistically longer survival was not supported by the log-rank test (P = .97), the Cox proportional hazard model, or the accelerated failure time model using the Gompertz distribution. The incremental cost-effectiveness ratio (€87 200) substantially exceeds the willingness to pay for 1 quality-adjusted life-year (€46 500)., Conclusions: This analysis indicates that adding pertuzumab cannot be considered cost-effective in Czechia. However, the observed phenomenon may be attributed to the limited duration of patient follow-up periods at the time of the study's execution (mean of 20-21 months). Importantly, we find that using states connected to specific treatment phases is appropriate for a retrospective analysis of patient-level clinical data., (Copyright © 2023 International Society for Health Economics and Outcomes Research. Published by Elsevier Inc. All rights reserved.)

Oxysterols, oxidized derivatives of cholesterol, act in breast cancer (BC) as selective estrogen receptor modulators and affect cholesterol homeostasis, drug transport, nuclear and cell receptors, and other signaling proteins. Using data from three highly overlapping sets of patients (N = 162 in total) with early-stage estrogen-receptor-positive luminal BC-high-coverage targeted DNA sequencing (113 genes), mRNA sequencing, and full micro-RNA (miRNA) transcriptome microarrays-we describe complex oxysterol-related interaction (correlation) networks, with validation in public datasets (n = 538) and 11 databases. The ESR1-CH25H-INSIG1-ABCA9 axis was the most prominent, interconnected through miR-125b-5p, miR-99a-5p, miR-100-5p, miR-143-3p, miR-199b-5p, miR-376a-3p, and miR-376c-3p. Mutations in SC5D, CYP46A1, and its functionally linked gene set were associated with multiple differentially expressed oxysterol-related genes. STARD5 was upregulated in patients with positive lymph node status. High expression of hsa-miR-19b-3p was weakly associated with poor survival. This is the first study of oxysterol-related genes in BC that combines DNA, mRNA, and miRNA multiomics with detailed clinical data. Future studies should provide links between intratumoral oxysterol signaling depicted here, circulating oxysterol levels, and therapy outcomes, enabling eventual clinical exploitation of present findings., (© 2023 The Authors. Molecular Oncology published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)

Introduction: Glomus jugulare tumours (GJT) are benign tumours that arise locally and destructively in the base of the skull and can be successfully treated with radiotherapy. Patients have a long-life expectancy and the late effects of radiotherapy can be serious. Proton radiotherapy reduces doses to critical organs and can reduce late side effects of radiotherapy. The aim of this study was to report feasibility and early clinical results of 12 patients treated using proton therapy., Methods: Between December 2013 and June 2019, 12 patients (pts) with GJT (median volume 20.4 cm 3 ; range 8.5-41 cm 3 ) were treated with intensity modulated proton therapy (IMPT). Median dose was 54 GyE (Gray Equivalents) (50-60 GyE) with daily fractions of 2 GyE. Twelve patients were analysed with a median follow-up time of 42.2 months (11.3-86.7). Feasibility, dosimetric parameters, acute and late toxicity and local effect on tumour were evaluated in this retrospective study., Results: All patients finished treatment without interruption, with excellent dosimetric parameters and mild acute toxicity. Stabilisation of tumour size was detected on MRI in all patients. No changes in symptoms were observed in comparison with pre-treatment conditions. No late effects of radiotherapy were observed., Conclusion: Pencil-beam scanning proton radiotherapy is highly feasible in the treatment of large GJT with mild acute toxicity and promising short-term results. Longer follow-up and larger patient cohorts are required to further identify the role of pencil-beam scanning (PBS) for this indication., (© 2022 The Authors. Journal of Medical Radiation Sciences published by John Wiley & Sons Australia, Ltd on behalf of Australian Society of Medical Imaging and Radiation Therapy and New Zealand Institute of Medical Radiation Technology.)

Introduction: Human kinesin 14 (KIF14) is one of the 70 prognostic marker genes (so-called Amsterdam profile) previously identified by the microarray of breast carcinomas, and its high transcript expression in tumor specimens indicates a poor prognosis for patients. We performed a pilot study to explore the prognostic and predictive meaning of KIF14 germline genetic variability in breast cancer patients., Methods: KIF14 coding sequence, including 5' and 3' untranslated regions and overlaps to introns for identification of splicing sites, was analyzed using next-generation sequencing in the testing set of blood DNA samples from 105 breast cancer patients with clinical follow-up. After rigorous evaluation of major allele frequency, haplotype blocks, in silico predicted functional aspects, expression quantitative trait loci, and clinical associations, eight single nucleotide variants were subsequently validated in the evaluation set of 808 patients., Results: Carriers of minor alleles G (rs17448931) or T (rs3806362) had significantly shorter overall survival than wild type homozygotes (p = 0.010 and p = 0.023, respectively) thus successfully replicating the results of the testing set. Both associations remained significant in the multivariate Cox regression analysis, including molecular subtype and stage as covariates (hazard ratio, HR = 1.7, 95% confidence interval (CI) = 1.1-2.8 for rs17448931 and HR = 1.9, CI 1.2-3.0 for rs3806362)., Discussion: In conclusion, our preliminary data suggest that minor alleles in rs17448931 and rs3806362 of KIF14 represent candidate biomarkers of poor prognosis of breast cancer patients. After pending validation in independent populations and eventual functional characterization, these candidates might become useful biomarkers in the clinics., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Oxysterols, oxidized derivatives of cholesterol, have been implicated in multiple pathologies, including cancer. In breast cancer, the link is especially strong due to interactions between oxysterols and estrogen receptor activity. Here, we provide the first dedicated study of 113 oxysterol-related genes in breast cancer patients of the luminal subtype, in terms of both their somatic and germline variability, using targeted high-throughput DNA sequencing of 100 normal-tumor pairs with very high coverage. In the full cohort, or subsets of patients stratified by therapy, we found 12 germline variants in ABCA1, ABCA8, ABCC1, GPR183, LDLR, MBTPS1, NR1I2, OSBPL2, OSBPL3, and OSBPL5 to associate with poor survival of patients and variants in ABCA8, ABCG2, and HSD3B7 (three in total) associated with better survival. However, no associations remained significant after correction for multiple tests. Analysis of somatic variants revealed significantly (after FDR correction) poorer survival in patients mutated in CYP46A1 and 9 interacting (according to STRING analysis) genes, as well as in OSBPL3 and a set of 20 genes that collectively associated with the progesterone receptor status of patients. We propose further exploration of these genes in an integrative manner together with gene expression and epigenomic data., Competing Interests: Declaration of competing interest Declarations of interest: none., (Copyright © 2022 Elsevier B.V. and Société Française de Biochimie et Biologie Moléculaire (SFBBM). All rights reserved.)

Hereditary tumor syndromes with a possible manifestation in the female internal genital tract represent a heterogeneous group of diseases. The two most common entities are the hereditary breast and ovarian cancer syndrome, and the Lynch syndrome. The less common syndromes include the rhabdoid tumor predisposition syndrome, Cowden syndrome, tuberous sclerosis complex, DICER1 syndrome, nevoid basal cell carcinoma syndrome, Peutz-Jeghers syndrome, von Hippel-Lindau disease, and hereditary leiomyomatosis and renal cell cancer syndrome. The goal of this manuscript is to provide a comprehensive overview of those hereditary tumor syndromes which can manifest in the area of the female genital system, with an emphasis on their summary, the characteristics of the tumors which can develop in association with these syndromes, and the approach to the processing of prophylactically removed tissues and organs. The issue of Lynch syndrome screening is also discussed.

Breast cancer is the most frequent cancer in the female population worldwide. The role of germline genetic variability in cytochromes P450 (CYP) in breast cancer prognosis and individualized therapy awaits detailed elucidation. In the present study, we used the next-generation sequencing to assess associations of germline variants in the coding and regulatory sequences of all human CYP genes with response of the patients to the neoadjuvant cytotoxic chemotherapy and disease-free survival (n = 105). A total of 22 prioritized variants associating with a response or survival in the above evaluation phase were then analyzed by allelic discrimination in the large confirmation set (n = 802). Associations of variants in CYP1B1 , CYP4F12 , CYP4X1 , and TBXAS1 with the response to the neoadjuvant cytotoxic chemotherapy were replicated by the confirmation phase. However, just association of variant rs17102977 in CYP4X1 passed the correction for multiple testing and can be considered clinically and statistically validated. Replicated associations for variants in CYP4X1 , CYP24A1 , and CYP26B1 with disease-free survival of all patients or patients stratified to subgroups according to therapy type have not passed a false discovery rate test. Although statistically not confirmed by the present study, the role of CYP genes in breast cancer prognosis should not be ruled out. In conclusion, the present study brings replicated association of variant rs17102977 in CYP4X1 with the response of patients to the neoadjuvant cytotoxic chemotherapy and warrants further research of genetic variation CYPs in breast cancer.

Breast cancer is the most common cancer in women in the world. The role of germline genetic variability in ATP-binding cassette (ABC) transporters in cancer chemoresistance and prognosis still needs to be elucidated. We used next-generation sequencing to assess associations of germline variants in coding and regulatory sequences of all human ABC genes with response of the patients to the neoadjuvant cytotoxic chemotherapy and disease-free survival ( n = 105). A total of 43 prioritized variants associating with response or survival in the above testing phase were then analyzed by allelic discrimination in the large validation set ( n = 802). Variants in ABCA4, ABCA9, ABCA12, ABCB5, ABCC5, ABCC8, ABCC11, and ABCD4 associated with response and variants in ABCA7, ABCA13, ABCC4 , and ABCG8 with survival of the patients. No association passed a false discovery rate test, however, the rs17822931 (Gly180Arg) in ABCC11, associating with response, and the synonymous rs17548783 in ABCA13 (survival) have a strong support in the literature and are, thus, interesting for further research. Although replicated associations have not reached robust statistical significance, the role of ABC transporters in breast cancer should not be ruled out. Future research and careful validation of findings will be essential for assessment of genetic variation which was not in the focus of this study, e.g., non-coding sequences, copy numbers, and structural variations together with somatic mutations.

Twenty percent of patients with high-tumor-burden (HTB) follicular lymphoma (FL) develop progression/relapse of disease (POD) within 24 months of frontline immunochemotherapy. Unfortunately, about 50% of these patients die within 5 years since POD event. Rituximab maintenance was proven to reduce relapse rate in responding FL, but its role on preventing POD was not defined. We analyzed 1360 HTB-FL patients from the Czech Lymphoma Study Group registry treated with frontline rituximab-containing regimen. Of those, 950 cases received rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) and achieved complete or partial remission: 712 patients received rituximab maintenance (MAINT) and 238 were a historical observational cohort (OBS). We have proposed a modified POD24 (mPOD24) endpoint for the chemosensitive patients calculated from the end-of-induction (EOI). Survival rates since EOI were as follows: 5-year overall survival (OS) 86.2% versus 94.5% in the OBS and MAINT groups, respectively ( P  < .001) and 5-year progression-free survival 58.5% (OBS) and 75.4% (MAINT) ( P  < .001). The Cox proportional hazards model showed a decrease in mPOD24 incidence in the MAINT group with the overall hazard rate reduced by 56% (hazard ratio = 0.44; P  < .001). The cumulative incidence of mPOD24 was reduced from 24.1% in OBS to 10.1% in MAINT ( P  < .001). Comparison of non-mPOD24 cases showed OS similar to that in the general population. Rituximab maintenance given after R-CHOP resulted in a 2.4-fold reduction in mPOD24 incidence. Once the non-POD24 status is achieved, FL does not shorten the patients' life expectancy., Competing Interests: Vít Procházka provided consultancy (F. Hoffmann‐La Roche AG) and received research funding (Takeda Pharmaceuticals, Inc); Marek Trněný received research funding (Seattle Genetics, Inc), provided consultancy (F. Hoffmann‐La Roche AG), and received speakers´ bureau (F. Hoffmann‐La Roche AG). Other authors declare no conflict of interest., (© 2020 The Authors. eJHaem published by British Society for Haematology and John Wiley & Sons Ltd.)

We studied the in vitro metabolism of the anti-thyroid-cancer drug vandetanib in a rat animal model and demonstrated that N-desmethylvandetanib and vandetanib N-oxide are formed by NADPH- or NADH-mediated reactions catalyzed by rat hepatic microsomes and pure biotransformation enzymes. In addition to the structural characterization of vandetanib metabolites, individual rat enzymes [cytochrome P450 (CYP) and flavin-containing monooxygenase (FMO)] capable of oxidizing vandetanib were identified. Generation of N-desmethylvandetanib, but not that of vandetanib N-oxide, was attenuated by CYP3A and 2C inhibitors while inhibition of FMO decreased formation of vandetanib N-oxide. These results indicate that liver microsomal CYP2C/3A and FMO1 are major enzymes participating in the formation of N-desmethylvandetanib and vandetanib N-oxide, respectively. Rat recombinant CYP2C11 > >3A1 > 3A2 > 1A1 > 1A2 > 2D1 > 2D2 were effective in catalyzing the formation of N-desmethylvandetanib. Results of the present study explain differences between the CYP- and FMO-catalyzed vandetanib oxidation in rat and human liver reported previously and the enzymatic mechanisms underlying this phenomenon., Competing Interests: Declaration of Competing Interest The authors declare that there are no conflicts of interest., (Copyright © 2019. Published by Elsevier B.V.)

The metabolism of vandetanib, a tyrosine kinase inhibitor used for treatment of symptomatic/progressive medullary thyroid cancer, was studied using human hepatic microsomes, recombinant cytochromes P450 (CYPs) and flavin-containing monooxygenases (FMOs). The role of CYPs and FMOs in the microsomal metabolism of vandetanib to N -desmethylvandetanib and vandetanib- N -oxide was investigated by examining the effects of CYP/FMO inhibitors and by correlating CYP-/FMO-catalytic activities in each microsomal sample with the amounts of N -desmethylvandetanib/vandetanib- N -oxide formed by these samples. CYP3A4/FMO-activities significantly correlated with the formation of N -desmethylvandetanib/ vandetanib- N -oxide. Based on these studies, most of the vandetanib metabolism was attributed to N -desmethylvandetanib/vandetanib- N -oxide to CYP3A4/FMO3. Recombinant CYP3A4 was most efficient to form N -desmethylvandetanib, while FMO1/FMO3 generated N -oxide. Cytochrome b 5 stimulated the CYP3A4-catalyzed formation of N -desmethylvandetanib, which is of great importance because CYP3A4 is not only most efficient in generating N -desmethylvandetanib, but also most significant due to its high expression in human liver. Molecular modeling indicated that binding of more than one molecule of vandetanib into the CYP3A4-active center can be responsible for the high efficiency of CYP3A4 N -demethylating vandetanib. Indeed, the CYP3A4-mediated reaction exhibits kinetics of positive cooperativity and this corresponded to the in silico model, where two vandetanib molecules were found in CYP3A4-active center.

Background: There is a steady decline in cancer mortality in Western Europe (WE), but this trend is not so obvious in Central and Eastern Europe (CEE). One of the largest discrepancies between WE and CEE is the level of investment in cancer care. The objective of our analysis was to examine the correlation between mortality-to-incidence (M/I) ratio and expenditures on oncology drugs in CEE and WE., Materials and Methods: This cross-sectional analysis was done on publicly available data. Data on expenditures for oncology drugs were obtained from QuintilesIMS, and data on M/I ratio from Globocan. The main outcome was mortality-to-incidence ratio, and the primary analysis was performed by Spearman's rank correlation., Results: There is a large discrepancy in expenditure on oncology drugs per cancer case between WE and CEE, and within CEE. Average expenditure on oncology drugs per capita as well as per new cancer case was 2.5 times higher in WE than in CEE. Availability of oncology drugs was highest in Germany (100%), relatively similar in WE (average of 91%), but in CEE it ranged from 37% to 86%, with an average of 70%. Annual expenditures on all oncology drugs per new cancer case was significantly negatively correlated with the M/I ratio (Spearman's ρ = -0.90, p < .001)., Conclusion: There is a financial threshold for oncology drugs per cancer case needed to increase survival. Based on significantly lower expenditures for oncology drugs in CEE in comparison with WE, more investment for drugs as well as better, more organized, value- oriented consumption is needed., Implications for Practice: Cancer is not treated equally successfully in Western Europe (WE) and in Central and Eastern Europe (CEE). This study showed that success in treatment of cancer is associated with the amount of money invested in oncology drugs. CEE countries spend on average 2.5 times less than WE countries for oncology drugs per new cancer case. These findings should be used by health care providers and oncologists struggling for more resources and better, more organized, evidence-based allocation of these resources as well as better oncology outcomes., Competing Interests: Disclosures of potential conflicts of interest may be found at the end of this article., (© AlphaMed Press 2018.)

Abstract: Ellipticine is an anticancer agent that forms covalent DNA adducts after enzymatic activation by cytochrome P450 (CYP) enzymes, mainly by CYP3A4. This process is one of the most important ellipticine DNA-damaging mechanisms for its antitumor action. Here, we investigated the efficiencies of human hepatic microsomes and human recombinant CYP3A4 expressed with its reductase, NADPH:CYP oxidoreductase (POR), NADH:cytochrome b 5 reductase and/or cytochrome b 5 in Supersomes™ to oxidize this drug. We also evaluated the effectiveness of coenzymes of two of the microsomal reductases, NADPH as a coenzyme of POR, and NADH as a coenzyme of NADH:cytochrome b 5 reductase, to mediate ellipticine oxidation in these enzyme systems. Using HPLC analysis we detected up to five ellipticine metabolites, which were formed by human hepatic microsomes and human CYP3A4 in the presence of NADPH or NADH. Among ellipticine metabolites, 9-hydroxy-, 12-hydroxy-, and 13-hydroxyellipticine were formed by hepatic microsomes as the major metabolites, while 7-hydroxyellipticine and the ellipticine N 2 -oxide were the minor ones. Human CYP3A4 in Supersomes™ generated only three metabolic products, 9-hydroxy-, 12-hydroxy-, and 13-hydroxyellipticine. Using the 32 P-postlabeling method two ellipticine-derived DNA adducts were generated by microsomes and the CYP3A4-Supersome system, both in the presence of NADPH and NADH. These adducts were derived from the reaction of 13-hydroxy- and 12-hydroxyellipticine with deoxyguanosine in DNA. In the presence of NADPH or NADH, cytochrome b 5 stimulated the CYP3A4-mediated oxidation of ellipticine, but the stimulation effect differed for individual ellipticine metabolites. This heme protein also stimulated the formation of both ellipticine-DNA adducts. The results demonstrate that cytochrome b 5 plays a dual role in the CYP3A4-catalyzed oxidation of ellipticine: (1) cytochrome b 5 mediates CYP3A4 catalytic activities by donating the first and second electron to this enzyme in its catalytic cycle, indicating that NADH:cytochrome b 5 reductase can substitute NADPH-dependent POR in this enzymatic reaction and (2) cytochrome b 5 can act as an allosteric modifier of the CYP3A4 oxygenase.