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PURPOSE: We evaluated the prevalence of homologous recombination deficiencies (HRD) to determine the efficacy of different techniques and clinical characteristics of patients. METHODS: This retrospective study included patients with metastatic prostate cancer who underwent molecular testing at our hospital between 2016 and 2022. We used tumor tissue, ctDNA, and lymphocytes for somatic or germline testing. We analyzed the clinical characteristics and survival outcomes. RESULTS: 144 patients were tested (113 somatic, 21 germline, and 10 both). Technical issues prevented the analysis of 23 prostatic samples (18.7%). 12 (8.3%) patients had HRD. BRCA2 was the most frequent mutation (66.7%). Patients with HRD were younger (57.5 years). Patients with BRCA mutations had poorer survival (31.9 vs 56.3 months, p = 0.048). CONCLUSION: In our institution, 8.3% of the patients had HRD. Tumor tissue analysis failed in 18.7% of tests. ctDNA analysis is an alternative detection method. BRCA mutations are correlated with poor prognosis.
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Proteína BRCA2 , Recombinação Homóloga , Neoplasias da Próstata , Humanos , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/mortalidade , Idoso , Proteína BRCA2/genética , Mutação , Prognóstico , DNA Tumoral Circulante/genética , DNA Tumoral Circulante/sangue , Idoso de 80 Anos ou mais , Mutação em Linhagem Germinativa , Proteína BRCA1/genética , AdultoRESUMO
PURPOSE: RAS (KRAS/NRAS) mutational status on a tumor biopsy is mandatory to guide the best treatment in metastatic colorectal cancer (mCRC). Determining the RAS mutational status by tumor-tissue biopsy is essential in guiding the optimal treatment decision for mCRC. RAS mutations are negative predictive factors for the use of EGFR monoclonal antibodies. Cell-free DNA (cfDNA) analysis enables minimally invasive monitoring of tumor evolution. METHODS/PATIENTS: PERSEIDA was an observational, prospective study assessing cfDNA RAS, BRAF and EGFR mutations (using Idylla™) in first-line mCRC, RAS wild-type (baseline tumor-tissue biopsy) patients (cohort 2). Plasma samples were collected before first-line treatment, after 20 ± 2 weeks, and at disease progression. RESULTS: 117 patients were included (103 received panitumumab + chemotherapy as first-line treatment). At baseline, 7 (6.8%) patients had RAS mutations, 4 (3.9%) BRAF mutations and no EGFR mutations were detected (cfDNA, panitumumab + chemotherapy subpopulation [panitumumab + Ch]). The baseline RAS mutational status concordance between tissue and liquid biopsies was 94.0% (93.2%, panitumumab + Ch). At 20 weeks, only one patient in the study (included in the panitumumab + Ch) had an emerging cfDNA RAS mutation. No emerging BRAF or EGFR mutations were reported. At disease progression, 6 patients had emergent mutations not present at baseline (RAS conversion rate: 13.3% [6/45]; 15.0% [6/40], panitumumab + Ch). CONCLUSIONS: The concordance rate between liquid and solid biopsies at baseline was very high, as previously reported, while our results suggest a considerable emergence of RAS mutations during disease progression. Thus, the dynamics of the genomic landscape in ctDNA may provide relevant information for the management of mCRC patients.
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Ácidos Nucleicos Livres , Neoplasias Colorretais , Mutação , Panitumumabe , Proteínas Proto-Oncogênicas B-raf , Humanos , Neoplasias Colorretais/genética , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/patologia , Neoplasias Colorretais/sangue , Feminino , Masculino , Estudos Prospectivos , Idoso , Pessoa de Meia-Idade , Ácidos Nucleicos Livres/genética , Ácidos Nucleicos Livres/sangue , Proteínas Proto-Oncogênicas B-raf/genética , Panitumumabe/uso terapêutico , Proteínas Proto-Oncogênicas p21(ras)/genética , Receptores ErbB/genética , Adulto , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , GTP Fosfo-Hidrolases/genética , Progressão da Doença , Proteínas de Membrana/genéticaRESUMO
PURPOSE: Small bowel adenocarcinoma (SBA) is a rare malignancy of the gastrointestinal tract, and its unique location within the small intestine presents difficulties in obtaining tissue samples from the lesions. This limitation hinders the research and development of effective clinical treatment methods. Circulating tumor DNA (ctDNA) analysis holds promise as an alternative approach for investigating SBA and guiding treatment decisions, thereby improving the prognosis of SBA. METHODS: Between January 2017 and August 2021, a total of 336 tissue or plasma samples were obtained and the corresponding mutation status in tissue or blood was evaluated with NGS. RESULTS AND CONCLUSIONS: The study found that in SBA tissues, the most commonly alternated genes were TP53, KRAS, and APC, and the most frequently affected pathways were RTK-RAS-MAPK, TP53, and WNT. Notably, the RTK-RAS-MAPK pathway was identified as a potential biomarker that could be targeted for treatment. Then, we validated the gene mutation profiling of ctDNA extracted from SBA patients exhibited the same characteristics as tissue samples for the first time. Subsequently, we applied ctDNA analysis on a terminal-stage patient who had shown no response to previous chemotherapy. After detecting alterations in the RTK-RAS-MAPK pathway in the ctDNA, the patient was treated with MEK + EGFR inhibitors and achieved a tumor shrinkage rate of 76.33%. Our study utilized the largest Chinese SBA cohort to uncover the molecular characteristics of this disease, which might facilitate clinical decision making for SBA patients.
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Adenocarcinoma , DNA Tumoral Circulante , Neoplasias Intestinais , Mutação , Humanos , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenocarcinoma/tratamento farmacológico , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Neoplasias Intestinais/genética , Neoplasias Intestinais/patologia , DNA Tumoral Circulante/genética , DNA Tumoral Circulante/sangue , Biomarcadores Tumorais/genética , Intestino Delgado/patologia , Adulto , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteína Supressora de Tumor p53/genética , Proteína da Polipose Adenomatosa do Colo/genética , China , Prognóstico , População do Leste AsiáticoRESUMO
Liquid biopsy, specifically the analysis of circulating tumor DNA (ctDNA), offers a non-invasive approach for hepatocellular carcinoma (HCC) diagnosis and management. However, its implementation in the clinical setting is difficult due to challenges such as low ctDNA yield and difficulty in understanding the mutation signals from background noise. This review highlights the crucial role of artificial intelligence (AI) in addressing these limitations and in improving discoveries in the field of liquid biopsy for HCC care. Combining AI with liquid biopsy data can offer a promising future for the discovery of novel biomarkers and an AI-powered clinical decision support system (CDSS) can turn liquid biopsy into an important tool for personalized management of HCC. Despite the current challenges, the integration of AI shows promise to significantly improve patient outcomes and revolutionize the field of oncology.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Medicina de Precisão , Inteligência Artificial , Biomarcadores Tumorais/genética , Biópsia LíquidaRESUMO
BACKGROUND: HPV-16 driven oropharynx/oral cavity squamous cell carcinomas prevalence varies globally. We evaluated the presence of HPV-16 ctDNA and HPV-16 E6 antibodies in samples obtained from participants treated at the Instituto do Cancer do Estado de Sao Paulo, ICESP, and from whom tumoral HPV DNA, HPV-16 E6*I mRNA, and p16INK4a status was also accessed. METHODS: HPV was genotyped by PCR-hybridization. All HPV DNA positive and â¼10 % HPV DNA negative cases underwent p16INK4a immunohistochemistry and E6*I RNA testing using a multiplex bead based protocol. HPV-16 ctDNA and anti-E6 antibodies were assessed by ddPCR (digital droplet PCR) and multiplex serology, respectively. RESULTS: The prevalence of HPV-16 in oropharynx carcinoma (OPC) cases was low (8.7 %) when considering solely HPV-16 DNA detection, and even lower (5.2 %) when taken into consideration the concomitant detection of HPV-16 E6*I RNA and/or p16INK4 (HPV-16 attributable fraction - AF). None of the oral cavity cancer (OCC) cases were detected with HPV-16 DNA. HPV-16 ctDNA was more commonly detected than HPV-16 E6 antibodies (29.8 % versus 10.6 %). Both serum biomarkers attained 100 % sensitivity of detecting HPV-16 AF OPC, however the specificity of the HPV-16 anti-E6 biomarker was higher compared to ctDNA (93.2 % versus 75.0 %). Finally, when both HPV-16 ctDNA and anti-E6 biomarkers were considered together, the sensitivity and specificity for HPV-16 OPC detection was 100 % and about 70 %, respectively, independently of analyzing HPV-16 DNA positive or HPV-16 AF tumors. CONCLUSIONS: Our findings corroborate that serum biomarkers are highly sensitive and specific biomarkers for detection of HPV-associated OPC.
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Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Neoplasias Orofaríngeas , Infecções por Papillomavirus , Humanos , Papillomavirus Humano 16/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Brasil/epidemiologia , Neoplasias Bucais/complicações , Biomarcadores , DNA Viral/análise , RNA , Neoplasias de Cabeça e Pescoço/complicaçõesRESUMO
BACKGROUND: Liquid biopsy (LB) is used to detect epidermal growth factor receptor (EGFR) mutations in non-small cell lung cancer (NSCLC) and has been demonstrated to have prognostic and predictive value. OBJECTIVE: To associate the rates of EGFR and T790M mutations detected by LB during disease progression after first- or second-generation EGFR-TKIs with clinical characteristics and survival outcomes. METHODS: From January 2018 to December 2021, 295 patients with advanced EGFR mutant (EGFRm) NSCLC treated with first- or second-generation EGFR-TKIs were retrospectively analyzed. LB was collected at the time of progression. The frequency of EGFRT790M mutations, overall survival (OS), and the clinical characteristics associated with LB positivity were determined. RESULTS: The prevalence of EGFRT790M mutation detected using LB was 44%. In patients with negative vs. positive LB, the median OS was 45.0 months vs. 25.0 months (p= 0.0001), respectively. Patients with a T790M mutation receiving osimertinib had a median OS of 44 months (95% CI [33.05-54.99]). Clinical characteristics associated with positive LB at progression extra-thoracic involvement, > 3 metastatic sites, and bone metastases. CONCLUSIONS: Our findings showed that LB positivity was associated with worse survival outcomes and specific clinical characteristics. This study also confirmed the feasibility and detection rate of T790M mutation in a Latin American population.
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Introduction: Liquid biopsy is a non-invasive method used to detect cancer and monitor treatment responses by analyzing blood or other bodily fluids for cancer biomarkers. Meningiomas are the most common primary central nervous system tumors, and biomarkers play a crucial role in their diagnosis, prognosis, and treatment monitoring. The World Health Organization (WHO) classifies meningiomas based on tumor grades and molecular alterations in genes such as in NF2, AKT1, TRAF7, SMO, PIK3CA, KLF4, SMARCE1, BAP1, H3K27me3, TERT promoter, and CDKN2A/B. Liquid biopsy, specifically cell-free DNA (cfDNA) analysis, has shown potential for monitoring meningiomas as it can detect ctDNA release in the blood, unaffected by the blood-brain barrier. MicroRNAs (miRNAs) have also been found to be deregulated in various cancers, including meningiomas, presenting potential as diagnostic biomarkers. Additionally, studying cytokines in the tumor microenvironment may aid in establishing prognostic or diagnostic panels for meningiomas. Methods: In the present study we analyzed the DNA coming from both the plasma and tumor samples, in addition to analyze miRNA-21 and cytokines in the plasma of 28 meningioma patients. Discussion and Conclusion: Our findings indicate that the detection of ctDNA in the plasma of meningioma patients is feasible. However, it's important to note that certain challenges persist when comparing plasma DNA analysis to that of tumor tissues. In our study, we observed a paired identification of mutations in only one patient, highlighting the complexities involved. Furthermore, we successfully identified miR-21 and cytokines in the plasma samples. Notably, our analysis of Interleukin 6 (IL-6) unveiled higher expression in the clear cell subtype compared to the other types. Despite the ongoing research, the clinical implementation of liquid biopsy in meningiomas remains somewhat limited. Nevertheless, our promising results underscore the need for further investigation.
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(1) Background: The epigenetic regulator EZH2 is a subunit of the polycomb repressive complex 2 (PRC2), and methylates H3K27, resulting in transcriptional silencing. It has a critical role in lymphocyte differentiation within the lymph node. Therefore, mutations at this level are implicated in lymphomagenesis. In fact, the mutation at the Y641 amino acid in the EZH2 gene is mutated in up to 40% of B-cell lymphomas. (2) Methods: We compared the presence of exon 16 EZH2 mutations in tumor samples and ctDNA in a prospective trial. These mutations were determined by Sanger sequencing and ddPCR. (3) Results: One hundred and thirty-eight cases were included. Ninety-eight were germinal center, and twenty had EZH2 mutations. Mean follow-up (IQR 25-75) was 23 (7-42) months. The tumor samples were considered the standard of reference. Considering the results of the mutation in ctDNA by Sanger sequencing, the sensibility (Se) and specificity (Sp) were 52% and 99%, respectively. After adding the droplet digital PCR (ddPCR) analysis, the Se and Sp increased to 95% and 100%, respectively. After bivariate analysis, only the presence of double-hit lymphoma (p = 0.04) or EZH2 mutations were associated with relapse. The median Progression free survival (PFS) (95% interval confidence) was 27.7 (95% IC: 14-40) vs. 44.1 (95% IC: 40-47.6) months for the mutated vs. wild-type (wt) patients. (4) Conclusions: The ctDNA is useful for analyzing EZH2 mutations, which have an impact on PFS.
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OBJECTIVE: To evaluate the relationship between circulating tumor DNA (ctDNA) presence and tumor features including tumor-infiltrating lymphocyte (TIL) levels in Peruvian breast cancer patients. MATERIALS AND METHODS: This was a prospective study conducted at the Instituto Nacional de Enfemedades Neoplasicas, Peru. We evaluated level of TIL and PIK3CA mutations in ctDNA. Clinical characteristics, including outcome data, were collected from the patient file. Survival was calculated from the date of blood sample drawn to the event time. Data collected were analyzed using SPSS software version 25. RESULTS: We analyzed plasma samples from 183 breast cancer patients. most cases were of Luminal-B (44.8%) phenotype and stage II (41.5%), and median stromal TIL was 30%. PIK3CA mutation in ctDNA was detected in 35% cases (most with E545K) and was associated with lower TIL level (p=0.04). PIK3CA in ctDNA tended to be associated with advanced stages (p=0.09) in the whole series and with higher recurrence rates (p=0.053) in the non-metastatic setting. Patients with presence of PIK3CA in ctDNA tended to have shorter survival (p=0.083). CONCLUSION: Presence of PIK3CA mutation in ctDNA was frequently found in our Peruvian breast cancer series, was associated with lower TIL levels and tended to predict poor outcomes.
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DNA Tumoral Circulante , Neoplasias , Linfócitos do Interstício Tumoral/patologia , Peru , Estudos Prospectivos , Classe I de Fosfatidilinositol 3-Quinases/genética , DNA Tumoral Circulante/genética , Mutação , Biomarcadores Tumorais/genética , Neoplasias/patologiaRESUMO
INTRODUCTION: Breast cancer (BC) is the malignant neoplasm with the highest mortality rate in women and female dogs are good models to study BC. OBJECTIVE: We investigated the efficacy of liquid biopsy to detect gene mutations in the diagnosis and follow-up of women and female dogs with BC. MATERIALS AND METHODS: In this study, 57 and 37 BC samples were collected from women and female dogs, respectively. After core biopsy and plasma samples were collected, the DNA and ctDNA of the tumor fragments and plasma were processed for next generation sequencing (NGS) assay. After preprocessing of the data, they were submitted to the Genome Analysis ToolKit (GATK). RESULTS: In women, 1788 variants were identified in tumor fragments and 221 variants in plasma; 66 variants were simultaneously detected in tumors and plasma. Conversely, in female dogs, 1430 variants were found in plasma and 695 variants in tumor fragments; 59 variants were simultaneously identified in tumors and plasma. The most frequently mutated genes in the tumor fragments of women were USH2A, ATM, and IGF2R; in female dogs, they were USH2A, BRCA2, and RRM2. Plasma of women showed the most frequent genetic variations in the MAP3K1, BRCA1, and GRB7 genes, whereas plasma from female dogs had variations in the NF1, ERBB2, and KRT17 genes. Mutations in the AKT1, PIK3CA, and BRIP genes were associated with tumor recurrence, with a highly pathogenic variant in PIK3CA being particularly prominent. We also detected a gain-of-function mutation in the GRB7, MAP3K1, and MLH1 genes. CONCLUSION: Liquid biopsy is useful to identify specific genetic variations at the beginning of BC manifestation and may be accompanied over the entire follow-up period, thereby supporting the clinicians in refining interventions.
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BACKGROUND: Few trials have evaluated the utility of liquid biopsies to detect epidermal growth factor receptor mutations (EGFRm) at the time of response evaluation and its association with the clinical characteristics and outcomes of non-small-cell lung cancer (NSCLC) patients. OBJECTIVE: This study aimed to evaluate, in a real-world clinical setting, the prevalence of plasma EGFRm and its association with the clinical characteristics, response and survival outcomes of NSCLC patients under treatment with EGFR-tyrosine kinase inhibitors (EGFR-TKIs). METHODS: This observational study enrolled advanced or metastatic NSCLC patients, with confirmed tumor EGFRm, receiving treatment with first- or second-generation EGFR-TKIs. Blood samples for the detection of plasma EGFRm were collected at the time of response evaluation and processed using the Target Selector™ assay. The main outcomes were the detection rate of plasma EGFRm, median Progression-Free Survival (PFS) and Overall Survival (OS) according to plasma EGFR mutational status. RESULTS: Of 84 patients, 50 (59.5%) had an EGFRm detected in plasma. After a median follow-up of 21.1 months, 63 patients (75%) had disease progression. The detection rate of plasma EGFRm was significantly higher in patients with disease progression than in patients with partial response or stable disease (68.3% versus 33.3%; P< 0.01). PFS and OS were significantly longer in patients without plasma EGFRm than among patients with plasma EGFRm (14.3 months [95% CI, 9.25-19.39] vs 11.0 months [95% CI, 8.61-13.46]; P= 0.034) and (67.8 months [95% CI, 39.80-95.94] vs 32.0 months [95% CI, 17.12-46.93]; P= 0.006), respectively. A positive finding in LB was associated with the presence of ⩾ 3 more metastatic sites (P= 0.028), elevated serum carcinoembryonic (CEA) at disease progression (P= 0.015), and an increase in CEA with respect to baseline levels (P= 0.038). CONCLUSIONS: In NSCLC patients receiving EGFR-TKIs, the detection of plasma EGFRm at the time of tumor response evaluation is associated with poor clinical outcomes.
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Carcinoma Pulmonar de Células não Pequenas/mortalidade , Neoplasias Pulmonares/mortalidade , Inibidores de Proteínas Quinases/uso terapêutico , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Análise Mutacional de DNA , Progressão da Doença , Receptores ErbB/sangue , Receptores ErbB/genética , Feminino , Humanos , Biópsia Líquida , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Inibidores de Proteínas Quinases/farmacologia , Medição de Risco/métodos , Medição de Risco/estatística & dados numéricosRESUMO
Circulating tumor DNA (ctDNA) in fluids has gained attention because ctDNA seems to identify tumor-specific abnormalities, which could be used for diagnosis, follow-up of treatment, and prognosis: the so-called liquid biopsy. Liquid biopsy is a minimally invasive approach and presents the sum of ctDNA from primary and secondary tumor sites. It has been possible not only to quantify the amount of ctDNA but also to identify (epi)genetic changes. Specific mutations in genes have been identified in the plasma of patients with several types of cancer, which highlights ctDNA as a possible cancer biomarker. However, achieving detectable concentrations of ctDNA in body fluids is not an easy task. ctDNA fragments present a short half-life, and there are no cut-off values to discriminate high and low ctDNA concentrations. Here, we discuss the use of ctDNA as a cancer biomarker, the main methodologies, the inherent difficulties, and the clinical predictive value of ctDNA.
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DNA Tumoral Circulante , Neoplasias , Biomarcadores Tumorais/genética , DNA Tumoral Circulante/genética , Humanos , Biópsia Líquida , Mutação , Neoplasias/diagnóstico , Neoplasias/genéticaRESUMO
The proportion of cancer patients with tumours that harbour a potentially targetable genomic alteration is growing considerably. The diagnosis of these genomic alterations can lead to tailored treatment at the onset of disease or on progression and to obtaining additional predictive information on immunotherapy efficacy. However, in up to 25% of cases, the initial tissue biopsy is inadequate for precision oncology and, in many cases, tumour genomic profiling at progression is not possible due to technical limitations of obtaining new tumour tissue specimens. Efficient diagnostic alternatives are therefore required for molecular stratification, which includes liquid biopsy. This technique enables the evaluation of the tumour genomic profile dynamically and captures intra-patient genomic heterogeneity as well. To date, there are several diagnostic techniques available for use in liquid biopsy, each one of them with different precision and performance levels. The objective of this consensus statement of the Spanish Society of Pathology and the Spanish Society of Medical Oncology is to evaluate the viability and effectiveness of the different methodological approaches in liquid biopsy in cancer patients and the potential application of this method to current clinical practice. The experts contributing to this consensus statement agree that, according to current evidence, liquid biopsy is an acceptable alternative to tumour tissue biopsy for the study of biomarkers in various clinical settings. It is therefore important to standardise pre-analytical and analytical procedures, to ensure reproducibility and generate structured and accessible clinical reports. It is essential to appoint multidisciplinary tumour molecular boards to oversee these processes and to enable the most suitable therapeutic decisions for each patient according to the genomic profile.
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Biópsia Líquida/normas , Oncologia/normas , Neoplasias/patologia , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Consenso , Genômica , Humanos , Biópsia Líquida/métodos , Oncologia/organização & administração , Neoplasias/genética , Medicina de Precisão , Reprodutibilidade dos Testes , EspanhaRESUMO
Lawsone itself exhibits interesting biological activities, and its complexation with a metal center can improve the potency. In this context a cytotoxic Ru-complex, [Ru(law)(dppb)(bipy)] (law = lawsone, dppb = 1,4-bis(diphenylphosphino)butane and bipy = 2,2'-bipyridine), named as CBLAU, was prepared as reported. In this work, NMR binding-target studies were performed to bring to light the most accessible interaction sites of this Ru-complex toward Calf-Thymus DNA (CT-DNA, used as a model), in a similar approach used for other metallic complexes with anti-cancer activity, such as cisplatin and carboplatin. Advanced and robust NMR binding-target studies, among them Saturation Transfer Difference (STD)-NMR and longitudinal relaxometry (T1), were explored. The 1H and 31P -NMR data indicate that the structure of Ru-complex remains preserved in the presence of CT-DNA, and some linewidth broadening is also observed for all the signals, pointing out some interaction. Looking at the binding efficiency, the T1 values are highly influenced by the formation of the CBLAU-DNA adduct, decreasing from 11.4 s (without DNA) to 1.4 s (with DNA), where the difference is bigger for the lawsone protons. Besides, the STD-NMR titration experiments revealed a stronger interaction (KD = 5.9 mM) for CBLAU-DNA in comparison to non-complexed lawsone-DNA (KD = 34.0 mM). The epitope map, obtained by STD-NMR, shows that aromatic protons from the complexed lawsone exhibits higher saturation transfer, in comparison to other Ru-ligands (DPPB and bipy), suggesting the supramolecular contact with CT-DNA takes place by the lawsone face of the Ru-complex, possibly by a spatial π-π stacking involving π-bonds on nucleic acids segments of the DNA chain and the naphthoquinone group.
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Four copper(II) coordination compounds from 2-benzimidazole propionic acid (Hbzpr) and 4-(benzimidazol-2-yl)-3-thiobutanoic acid (Hbztb) were synthesized and fully characterized by elemental analyses, electronic spectroscopy, FT-IR and mass spectrometry. The molecular structure for the four complexes was confirmed by single-crystal X-ray crystallography. The DNA-interacting properties of the two trinuclear and two mononuclear compounds were investigated using different spectroscopic techniques including absorption titration experiments, fluorescence spectroscopy and circular dichroism spectroscopy. Trinuclear [Cu3(bzpr)4(H2O)2](NO3)2·3H2O·CH3OH (2) and [Cu3(bzpr)4Cl2]·3H2O (3) bind to DNA through non-intercalative interactions, while for mononuclear [Cu(bzpr)2(H2O)]·2H2O (1) and [Cu(bztb)2]·2H2O (4), at minor concentrations in relation to the DNA, a groove binding interaction is favored, while at higher concentrations an intercalative mode is preferred. The nuclease properties of all complexes were studied by gel electrophoresis, which showed that they were able to cleave supercoiled plasmid DNA (form I) to the nicked form (form II). Compound 4 is even capable of generating linear form III (resulting from double-strand cleavage). The proposed mechanism of action involves an oxidative pathway (Fenton-type reaction), which produces harmful reactive species, like hydroxyl radicals.
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Benzimidazóis/farmacologia , Complexos de Coordenação/farmacologia , Cobre/farmacologia , DNA/efeitos dos fármacos , Benzimidazóis/química , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , Cobre/química , Cristalografia por Raios X , Clivagem do DNA , Ligantes , Modelos Moleculares , Estrutura Molecular , PlasmídeosRESUMO
Background: The observation of tumor-derived cell-free DNA (ctDNA) in plasma brought new expectations to monitor treatment response in cancer patients. Case presentation: In an exploratory case of a 57-year-old man diagnosed with metastatic sigmoid adenocarcinoma, we used a hotspot panel of cancer-associated gene mutations to identify tumor-specific mutations in the primary tumor and metastasis. RESULTS: Five mutations were detected (KRAS, p.Gly12Val; TP53, p.Arg175His; RB1, p.Ile680Thr; ALK, p.Gly1184Glu; and ERBB2, p.Lys860Lys), of which three were detected in both tissue types (primary tumor and metastasis). All five mutations were monitored in the ctDNA of six serial plasma samples. Only KRAS and TP53 mutations were detected at a high frequency in the first plasma sample. After 1 month of chemotherapy the allele frequencies of both mutations fell below the detection limit. From the third month of systemic treatment onward, the allele frequencies of both mutations were detectable in plasma, displaying a continual increase thereafter. The remaining three mutations were not detected in plasma samples. Signs of disease progression in ctDNA during the treatment period were evident while computed tomography (CT) measurements suggested stable metastatic lesions throughout the treatment. Conclusions: Liquid biopsies revealed tumor heterogeneity and predicted tumor progression, demonstrating the potential of ctDNA analysis to be a sensitive and specific tool for monitoring treatment responsivity and for early identification of treatment resistance.
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PURPOSE: The analysis of epidermal growth factor receptor (EGFR) mutations in many patients with advanced non-small-cell lung cancer (aNSCLC) has provided the opportunity for successful treatment with specific, targeted EGFR tyrosine kinase inhibitors. However, this therapeutic decision may be challenging when insufficient tumor tissue is available for EGFR mutation testing. Therefore, blood surrogate samples for EGFR mutation analysis have been suggested. METHODS: Data were collected from the Spanish cohort of patients in the large, non-interventional, diagnostic ASSESS study (NCT01785888) evaluating the utility of circulating free tumor-derived DNA from plasma for EGFR mutation testing. The incidence of EGFR mutation in Spain and the level of concordance between matched tissue/cytology and plasma samples were evaluated. RESULTS: In a cohort of 154 eligible patients, EGFR mutations were identified in 15.1 and 11.0% of tumor and plasma samples, respectively. The most commonly used EGFR mutation testing method for the tumor tissue samples was the QIAGEN Therascreen® EGFR RGQ PCR kit (52.1%). Fragment Length Analysis + PNA LNA Clamp was used for the plasma samples. The concordance rate for EGFR mutation status between the tissue/cytology and plasma samples was 88.8%; the sensitivity was 45.5%, and the specificity was 96.7%. CONCLUSIONS: The high concordance between the different DNA sources for EGFR mutation testing supports the use of plasma samples when tumor tissue is unavailable.
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Carcinoma Pulmonar de Células não Pequenas/genética , DNA Tumoral Circulante/análise , Análise Mutacional de DNA/métodos , Neoplasias Pulmonares/genética , Adulto , Idoso , DNA Tumoral Circulante/genética , Receptores ErbB/sangue , Receptores ErbB/genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Reação em Cadeia da Polimerase/métodos , Sensibilidade e Especificidade , EspanhaRESUMO
PURPOSE: Identifying patients who are at risk of relapse is a key challenge of primary breast cancer. The current study investigates the utility of urinary DNA in breast cancer management and as a predictor of relapse. This work also compares the sensitivity of plasma DNA with urinary DNA. METHODS: Blood plasma and urine specimens were collected concurrently from 200 breast cancer patients receiving neoadjuvant chemotherapy. Comparison of both plasma and urinary DNA was performed at baseline to determine assay significance. Serial measurements of urinary DNA were conducted to gauge DNA variations after surgery. Correlations to disease relapse were performed to affirm the clinical utility of urinary DNA. RESULTS: Molecular analysis showed patients were successfully identified with mutant PIK3CA using urinary DNA. A strong correlation was affirmed from urinary and plasma DNA at baseline with the correlation coefficient r = 0.859. We analyzed post-surgery measurements of urinary DNA for disease-relapse predictions. In subsequent serial followup of urinary DNA samples, we confirmed increased sensitivity in predicting relapse of these patients. The hazard ratio determined at the 9-month was 1.51 that identified patients at greater risk of disease relapse. CONCLUSION: Urinary DNA offers a unique opportunity to glimpse upon dynamic changes in early breast cancer. Our results demonstrated good correlation to plasma DNA and post monitoring of cancer patients to identify individuals susceptible to a high risk of relapse. This potentially allows for early intervention such as adjuvant chemotherapy to be administered to better manage these patients.
Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , DNA de Neoplasias/sangue , DNA de Neoplasias/urina , Recidiva Local de Neoplasia/patologia , Idoso , Neoplasias da Mama/sangue , Neoplasias da Mama/terapia , Neoplasias da Mama/urina , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/terapia , Recidiva Local de Neoplasia/urina , Prognóstico , Estudos Prospectivos , Taxa de SobrevidaRESUMO
Thirty-nine Schiff bases were synthesized by performing microwave-assisted condensation of the corresponding aldehydes and aromatic amines. Their reactive nitrogen species (RNS) scavenging activity and inhibitory effects against cancer cell growth were then subsequently investigated. Additionally, the interaction between the calf thymus DNA (ctDNA) and selected Schiff bases was evaluated using fluorescence spectroscopy, and their binding parameters were determined. The yields of the various compounds ranged from moderate to excellent (43-99%) after only a 2-min reaction. The hydroxylated Schiff bases 2, 8, 15, 16, 18, 20, 29, 32, 34, and 37 were found to be potent scavengers of 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals with half-maximal scavenging concentration (SC50) values lower than that of the positive control, resveratrol. The presence of hydroxyl substituents on the aromatic rings also proved essential to the cytotoxicity of the compounds. The binding constants (Kb) obtained using fluorescence spectroscopy ranged from 0.37 to 3.07×105Lmol-1, and were strongly influenced by the structure and hydroxylation degree. Schiff bases 3 and 8 showed promising cytotoxic activity, with half-maximal growth inhibitory (GI50) values in the same order of magnitude as those exhibited by the reference drug, doxorubicin against various cell lines. Interestingly, these compounds also showed the highest Kb, suggesting that the cytotoxic activity could be related to their interaction with the DNA of the tumor cells. The results of this study highlighted some Schiff bases as potential lead compounds for the design of new free radical scavengers and anticancer agents.
Assuntos
Antineoplásicos/química , DNA/química , Sequestradores de Radicais Livres/química , Bases de Schiff/química , Animais , Antineoplásicos/toxicidade , Bovinos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , DNA/metabolismo , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Cinética , Espécies Reativas de Nitrogênio/química , Bases de Schiff/metabolismo , Bases de Schiff/toxicidade , TermodinâmicaRESUMO
Neoadjuvant chemoradiotherapy (nCRT) followed by surgery is the mainstay treatment for locally advanced rectal cancer. Variable degrees of tumor regression are observed after nCRT and alternative treatment strategies, including close surveillance without immediate surgery, have been investigated to spare patients with complete tumor regression from potentially adverse outcomes of radical surgery. However, clinical and radiological assessment of response does not allow accurate identification of patients with complete response. In addition, surveillance for recurrence is similarly important for these patients, as early detection of recurrence allows salvage resections and adjuvant interventions. We report the use of liquid biopsies and personalized biomarkers for monitoring treatment response to nCRT and detecting residual disease and recurrence in patients with rectal cancer. We sequenced the whole-genome of four rectal tumors to identify patient-specific chromosomal rearrangements that were used to monitor circulating tumor DNA (ctDNA) in liquid biopsies collected at diagnosis and during nCRT and follow-up. We compared ctDNA levels to clinical, radiological and pathological response to nCRT. Our results indicate that personalized biomarkers and liquid biopsies may not be sensitive for the detection of microscopic residual disease. However, it can be efficiently used to monitor treatment response to nCRT and detect disease recurrence, preceding increases in CEA levels and radiological diagnosis. Similar good results were observed when assessing tumor response to systemic therapy and disease progression. Our study supports the use of personalized biomarkers and liquid biopsies to tailor the management of rectal cancer patients, however, replication in a larger cohort is necessary to introduce this strategy into clinical practice.