BACKGROUND: Resistance to chemotherapy is a major problem in the treatment of patients with triple-negative breast cancer (TNBC). Preclinical data suggest that TNBC is dependent on proteasomes; however, clinical observations indicate that the efficacy of proteasome inhibitors in TNBC may be limited, suggesting the need for combination therapies. METHODS: We compared bortezomib and carfilzomib and their combinations with nelfinavir and lopinavir in TNBC cell lines and primary cells with regard to their cytotoxic activity, functional proteasome inhibition, and induction of the unfolded protein response (UPR). Furthermore, we evaluated the involvement of sXBP1, ABCB1, and ABCG2 in the cytotoxic activity of drug combinations. RESULTS: Carfilzomib, via proteasome β5 + β2 inhibition, is more cytotoxic in TNBC than bortezomib, which inhibits β5 + β1 proteasome subunits. The cytotoxicity of carfilzomib was significantly potentiated by nelfinavir or lopinavir. Carfilzomib with lopinavir induced endoplasmic reticulum stress and pro-apoptotic UPR through the accumulation of excess proteasomal substrate protein in TNBC in vitro. Moreover, lopinavir increased the intracellular availability of carfilzomib by inhibiting carfilzomib export from cells that express high levels and activity of ABCB1, but not ABCG2. CONCLUSION: Proteasome inhibition by carfilzomib combined with nelfinavir/lopinavir represents a potential treatment option for TNBC, warranting further investigation.

• MeSH
• ABC transportér z rodiny G, člen 2 * metabolismus   antagonisté a inhibitory   MeSH
• apoptóza účinky léků   MeSH
• bortezomib * farmakologie   MeSH
• inhibitory HIV-proteasy * farmakologie   MeSH
• inhibitory proteasomu farmakologie   MeSH
• lidé MeSH
• Lopinavir * farmakologie   MeSH
• nádorové buněčné linie MeSH
• nádorové proteiny antagonisté a inhibitory   metabolismus   MeSH
• nelfinavir * farmakologie   MeSH
• oligopeptidy * farmakologie   MeSH
• P-glykoproteiny metabolismus   MeSH
• protokoly protinádorové kombinované chemoterapie farmakologie   MeSH
• signální dráha UPR * účinky léků   MeSH
• stres endoplazmatického retikula účinky léků   MeSH
• synergismus léků * MeSH
• triple-negativní karcinom prsu * farmakoterapie   patologie   MeSH
• XBP1 metabolismus   genetika   MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

INTRODUCTION: The incidence of advanced oral cavity and oropharyngeal cancers is generally high. Treatment outcomes for patients, especially those unfit for comprehensive cancer treatment, are unsatisfactory. Therefore, the search for factors to predict response to treatment and increase overall survival is underway. OBJECTIVE: This study aimed to analyze the presence of 32 HPV genotypes in tumor samples of 34 patients and the effect of HPV status and RAD51 on overall survival. METHOD: Tumor samples of 34 patients with locally advanced oropharyngeal or oral cavity cancer treated with accelerated radiotherapy in monotherapy were analyzed using reverse hybridization and immunohistochemistry for the presence of HPV and RAD51. Its effect on overall survival was examined. RESULTS: Only two types of HPV were identified-HPV 16 (dominant) and HPV 66 (two samples). The HPV positivity was associated with a borderline insignificant improvement in 2-year (p = 0.083), 5-year (p = 0.159), and overall survival (p = 0.083). Similarly, the RAD51 overexpression was associated with borderline insignificant improvement in 2-year (p = 0.083) and 5-year (p = 0.159) survival. CONCLUSION: We found no statistically significant differences but detected trends toward improvement in the survival of HPV-positive and RAD51 overexpressing patients unfit for surgical treatment or chemotherapy treated with hyperfractionated radiotherapy. The trends, however, indicate that in a larger group of patients, the effects of these two parameters would likely be statistically significant.

• MeSH
• infekce papilomavirem * komplikace   MeSH
• lidé MeSH
• nádory orofaryngu * MeSH
• prognóza MeSH
• rekombinasa Rad51 MeSH
• spinocelulární karcinom * patologie   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH

Dysfunctional DNA repair with subsequent genome instability and high mutational burden represents a major hallmark of cancer. In established malignant tumors, increased DNA repair capacity mediates resistance to DNA-damaging therapeutics, including cytotoxic drugs, radiotherapy, and selected small molecules including inhibitors of poly (ADP-ribose) polymerase (PARP), Ataxia Telangiectasia Mutated (ATM), ataxia telangiectasia and Rad3-related protein (ATR), and Wee1 kinase (Wee1). In addition, DNA repair deficiency is not only associated with sensitivity to selected anticancer drugs, but also with increased mutagenicity and increased neoantigen load on tumor cells, resulting in increased immunogenicity and improved response to CTLA4- or PD-(L)1 targeting monoclonal antibodies. DNA damage response (DDR) is composed of complex signalling pathways, including the sensing of the DNA damage, signal transduction, cellular response pathways to DNA damage, and activation of DNA repair. DNA double strand breaks (DSBs) are the most dangerous form of DNA damage. Tumor cells are characterised by frequent accumulation of DSBs caused by either endogenous replication stress or the impact of cancer treatment, most prominently chemotherapy and radiotherapy. Therefore, response of cancer cells to DSBs represents a crucial mechanism for how tumors respond to systemic treatment or radiotherapy, and how resistance develops. Ample clinical evidence supports the importance of DDR associated kinases as predictive and prognostic biomarkers in cancer patients. The ATM-CHK2 and ATR-CHK1-WEE1 pathways initiate DNA DSB repair. In the current review, we focus on major DDR associated kinases including ATM, ATR, CHK1, CHK2, and WEE1, and discuss their potential prognostic and predictive value in solid malignancies.

• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

OBJECTIVES: DNA repair proteins have emerged as potential predictors for immunotherapy response alongside PD-L1 expression, tumor-infiltrating lymphocytes (TILs) and tumor mutational burden. We analyzed expression of PD-L1, TILs count and expression of the homologous recombination (HR) protein RAD51, as potential prognostic factors in patients with resected non-small-cell lung carcinoma (NSCLC). MATERIALS AND METHODS: Discovery set included 96 NSCLC patients from the University Hospital Olomouc (Czech Republic) and a replication set included 1109 NSCLC patients from University Hospital Zurich (Switzerland). Tissue microarrays (TMAs) were stained using the automated staining platform Ventana Benchmark Ultra with antibodies against RAD51,CD3, CD8, CD68 and PD-L1. RESULTS: Loss of nuclear RAD51 protein was associated with high TILs (r=-0.25, p = 0.01) and PD-L1 status (10.6 vs. 2.4 %, p = 0.012) in patients receiving neoadjuvant chemo-/radiotherapy (CT/RT). In silico analysis from the TCGA data set showed a negative relationship between RAD51 mRNA expression and CD45 (r = ‒0.422, p < 0.0001), CD68 (r = ‒0.326, p < 0.001), CD3 (r = ‒0.266, p < 0.001) and CD8 (r = ‒0.102, p < 0.001). RAD51 low/PD-L1 high patients were clustered as separate entity in the replication set and in TCGA dataset. High TILs status was significantly associated with improved OS in the replication set (unadjusted HR = 0.57, 95 % CI 0.42-0.76, p < 0.001). Similar results have been seen for CD3, CD8 and CD68. CONCLUSIONS: In conclusion, RAD51 nuclear loss is weakly associated with increased TILs and high PD-L1 at the time of surgery in curatively resected NSCLC and after prior exposure to neoadjuvant chemo- or radiotherapy. Both high TILs and RAD51 nuclear loss were confirmed as independent prognostic factors in curatively resected NSCLC.

• MeSH
• antigeny CD274 genetika   MeSH
• lidé MeSH
• nádory plic * genetika   terapie   MeSH
• nemalobuněčný karcinom plic * genetika   terapie   MeSH
• oprava DNA MeSH
• prognóza MeSH
• rekombinasa Rad51 genetika   MeSH
• tumor infiltrující lymfocyty MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Švýcarsko MeSH

OBJECTIVES: LC3A protein is associated with autophagosomes, and LC3A immunohistochemistry (IHC) is used for the detection of autophagy activity. The aim of this study was to assess the prognostic value of LC3A expression in patients with resected non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: We used tissue microarrays (TMAs) constructed from 116 resected stage IB-III NSCLC patients. Standard immunohistochemistry was performed on formalin-fixed paraffin-embedded tissue sections using antibody against LC3A autophagic potein. Stained slides were scanned by Olympus dotSlide Digital Virtual Microscopy System (Japan) and the LC3A staining was evaluated digitally. Groups were compared using the Mann Whitney U test, and correlations were assessed using Spearman's rank test. Survival was calculated using Kaplan-Meier analysis. Primary study endpoint was overall survival (OS), secondardy study endpoint disease-free survival (DFS). Cut-off optimization for LC3A prognostic value was performed using the "cut-off finder' 'software (Charite, Berlin, Germany). In addition, the Kaplan Meier plotter (KmPlot) was used to assess the relationship between LC3A mRNA expression and clinical outcome (OS and DFS) in patients with NSCLC. RESULTS: From 116 patients, 88 tissue samples were available for final examination. No significant association was found between LC3A staining and other clinicopathological variables, including tumor grade, stage and histological subtype. A higher number of LC3A stone-like structures (SLSs) (>20), was significanly associated with poor OS (HR = 2.27, p = 0.011) and DFS (HR = 2.27, p = 0.003). A significant association between high LC3A mRNA and both a worse OS and worse DFS was found by KMPlot analysis in patients with stage I-III NSCLC. CONSLUSION: This retrospective study suggests that SLSs as assessed by LC3A IHC as well as LC3A mRNA expression has a clinically relevant negative prognostic value in patients with resected NSCLC, and should be further investigated.

• MeSH
• analýza přežití MeSH
• autofagie MeSH
• čipová analýza tkání MeSH
• imunohistochemie MeSH
• lidé MeSH
• messenger RNA genetika   MeSH
• nádorové biomarkery metabolismus   MeSH
• nádory plic imunologie   mortalita   MeSH
• nemalobuněčný karcinom plic imunologie   mortalita   MeSH
• pneumektomie MeSH
• prognóza MeSH
• proteiny asociované s mikrotubuly genetika   metabolismus   MeSH
• staging nádorů MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Targeting deficient mechanisms of cellular DNA repair still represents the basis for the treatment of the majority of solid tumors, and increased DNA repair capacity is a hallmark mechanism of resistance not only to DNA-damaging treatments such as cytotoxic drugs and radiotherapy, but also to small molecule targeted drugs such as inhibitors of poly-ADP ribose polymerase (PARP). Hence, there is substantial medical need for potent and convenient biomarkers of individual response to DNA-targeted treatment in personalized cancer care. RAD51 is a highly conserved protein that catalyzes DNA repair via homologous recombination, a major DNA repair pathway which directly modulates cellular sensitivity to DNA-damaging treatments. The clinical and biological significance of RAD51 protein expression is still under investigation. Pre-clinical studies consistently show the important role of nuclear RAD51 immunoreactivity in chemo- and radioresistance. Validating data from clinical trials however is limited at present, and some clinical studies show controversial results. This review gives a comprehensive overview on the current knowledge about the prognostic and predictive value of RAD51 protein expression and genetic variability in patients with solid malignancies.

• MeSH
• chemorezistence genetika   MeSH
• DNA nádorová účinky léků   účinky záření   MeSH
• geny BRCA1 MeSH
• geny BRCA2 MeSH
• individualizovaná medicína MeSH
• lidé MeSH
• nádorové biomarkery genetika   metabolismus   MeSH
• nádory farmakoterapie   genetika   metabolismus   radioterapie   MeSH
• oprava DNA genetika   MeSH
• PARP inhibitory terapeutické užití   MeSH
• polymorfismus genetický MeSH
• proliferace buněk genetika   MeSH
• rekombinační oprava DNA genetika   MeSH
• rekombinasa Rad51 genetika   metabolismus   MeSH
• tolerance záření genetika   MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

OBJECTIVES: In response to DNA damage, recombination proteins are relocalized into sub-nuclear complexes that are microscopically detected as RAD51-containing nuclear foci. We aimed for assessing the prognostic and predictive value of loss of nuclear RAD51 immunoreactivity ('RAD51 loss') in 2 independent stage I to III non-small cell lung cancer (NSCLC) patient cohorts undergoing surgical resection and eventual perioperative chemo-/radiotherapy (CT/RT). MATERIALS AND METHODS: The discovery set included 69 evaluable patients (19 adenocarcinomas, ADC, 50 squamous cell carcinomas, SCC) from Palacky University Hospital, 45/69 (65.2%) with additional platinum-based CT. The replication set entailed 845 evaluable patients (446 ADC, 399 SCC) from University Hospital Zurich, 308/845 (36.5%) with platinum based CT or RT. RAD51 loss was defined as ≤20% of tumor cell nuclei having any nuclear RAD51 expression. We assessed the prognostic value of RAD51 loss in all patients and its predictive value in patients receiving CT/RT. RESULTS: RAD51 loss was observed in 40/69 (58.0%) and 439/845 (51.9%) evaluable tumors in the discovery and replication set, respectively (p=0.34). It was more frequent in ADC compared to SCC (57.2% vs 47.4%, p=0.003). RAD51 loss was significantly associated with worse OS in both the discovery (adjusted HR=2.39, p=0.039) and replication set (adjusted HR=1.31, p=0.008). The unfavourable prognostic effect of RAD51 loss seen in the overall population was not observed in patients receiving perioperative CT (adjusted HR=1.07, p=0.73) or perioperative RT (adjusted HR=1.05, p=0.82). CONCLUSION: RAD51 loss has an unfavourable prognostic impact in NSCLC patients undergoing curative surgical resection, but it may have a favourable predictive value in the subgroup of patients receiving perioperative platinum-based CT or RT, most likely as a consequence of deficient DNA repair.

• MeSH
• dospělí MeSH
• farmakoterapie MeSH
• hrudní chirurgické výkony MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• nádory plic metabolismus   patologie   terapie   MeSH
• nemalobuněčný karcinom plic metabolismus   patologie   terapie   MeSH
• prediktivní hodnota testů MeSH
• prognóza MeSH
• radioterapie MeSH
• rekombinasa Rad51 metabolismus   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• staging nádorů MeSH
• výsledek terapie MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• mladý dospělý MeSH
• mužské pohlaví MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• multicentrická studie MeSH