25 research outputs found

    Rapid Detection of Quinolone Resistance Mutations in gyrA of Helicobacter pylori by Real-Time PCR

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    The treatment of infections by the gastric pathogen Helicobacter pylori (H. pylori) has become more difficult due to increased rates of resistances against various antibiotics. Typically, atriple therapy, employing a combination of at least two antibiotics and a proton pump inhibitor, is used to cure H. pylori infections. In case of first-line therapy failure, quinolones are commonly applied in a second-line therapy. To prevent second-line treatment failures, we developed an improved method to detect the most common quinolone-resistance mutations located in the quinolone-resistance-determining region (QRDR) of the bacterial gyrA gene. Biopsy material from the gastric mucosa of infected patients was used to identify quinolone-resistant strains before the onset of drug administration. Two different wild-type and six mutant QRDR sequences were included. Melting curve analyses were performed with corresponding gyrA plasmid DNAs using a real-time polymerase chain reaction (RT-PCR) assay. By applying a combination of only two different fluorescent probes, this assay allows wild-type sequences to be unambiguously distinguished from all known mutant QRDR sequences of H. pylori. Next, the T(m) values of patient DNAs were established, and the genotypes were confirmed by sequencing. Thus, quinolone-resistant H. pylori strains can be easily and quickly diagnosed before treatment, which will help to avoid the administration of ineffective drug regimes

    Factors influencing BRAFV600

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    Clinical relevance of neuroendocrine differentiation in non-small cell lung cancer assessed by immunohistochemistry : a retrospective study on 405 surgically resected cases

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    Neuroendocrine differentiation in non-small cell lung cancer is a common feature, which has caused contradictory conclusions concerning survival estimates and responsiveness to therapy. Aiming to clarify this conflict, we analyzed neuroendocrine differentiation by immunohistochemistry in 405 surgically resected non-small cell lung carcinomas using standardized tissue microarray platform and the currently recommended antibody panel consisting of chromogranin-A, synaptophysin, and neural-cell adhesion molecule. Diagnostic criteria provided by the World Health Organization were applied. Histological subtypes were primarily reclassified according to current guidelines, assisted by auxiliary immunohistochemistry. Extensive clinical data was acquired, enabling detailed clinicopathological correlation. Importantly, neuroendocrine differentiation assessed by immunohistochemistry showed no significant relation to overall survival estimates, which remained unaffected by histological subtype, neuroendocrine marker type, adjuvant therapy, and recurring disease. The only exception was a small group consisting of three large cell carcinomas, each expressing all three neuroendocrine markers and demonstrating decreased survival. In conclusion, additional immunohistochemical detection of neuroendocrine differentiation in non-small cell lung cancer is presently not of prognostic importance and does not justify a distinct consideration

    The prognostic impact of sex on surgically resected non-small cell lung cancer depends on clinicopathologic characteristics

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    The increasing incidence of lung cancer in women and their supposed survival advantage over men requires clarification of the significance of sex. Age, stage, histologic features, differentiation grade, and Ki-67 index were assessed in 405 surgically resected non-small cell lung cancers (NSCLCs) using a standardized tissue microarray platform. Women were associated with well/moderate tumor differentiation, a Ki-67 index of 3% or less, and adenocarcinoma histologic features. Female sex predicted increased survival time only by univariate analysis. Stratified by sex, increased survival was noted for women older than 64 years, with a tumor at postsurgical International Union Against Cancer stage I, with adenocarcinoma histologic features, with well- or moderately differentiated tumors, or with a Ki-67 index of 3% or less. Sex is not an independent prognostic parameter for patients with surgically resected NSCLC. Sex-linked differences are associated with other factors, thus simulating a prognostic impact of sex. This study elucidates sex-specific interactions between patient and tumor characteristics, which are pivotal toward improving prognostic accuracy, individualized therapies, and screening efforts

    Adjuvant chemotherapy in stage II and III colon cancer: the role of the “budding and TILs-(tumor-infiltrating lymphocytes) combination” as tumor-host antagonists

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    Purpose!#!To analyze the influence of adjuvant chemotherapy on the combination of tumor budding and tumor-infiltrating lymphocytes (TILs) in stage II and III colon cancer and to elucidate its potential value for adjuvant treatment decisions.!##!Methods!#!306 patients with stage II and 205 patients with stage III colon cancer diagnosed between 2005 and 2016 who had undergone surgery in a curative setting were enrolled. Budding and TILs were assessed according to the criteria of the International Tumor Budding Consensus Conference (ITBCC) and the criteria of the International TILs Working Group (ITWG). Combinations of budding and TILs were analyzed, and the influence of adjuvant chemotherapy was assessed.!##!Results!#!In stage II colon cancer, stratification into the four budding/TILs groups showed no significant differences in overall survival (OS) between the chemotherapy and the surgery-alone group, not even in cases with high-risk features. In stage III colon cancer, patients with low budding/high TILs benefited significantly from chemotherapy (p=0.005). Patients with high budding/low TILs as well as high budding/high TILs showed a trend to benefit from adjuvant treatment. However, no chemotherapy benefit was seen for the low budding/low TIL group.!##!Conclusions!#!The budding/TIL combination identified subgroups in stage II and III colon cancer with and without benefit from adjuvant treatment. The results this study suggest that the combination of budding and TILs as tumor-host antagonists might be an additional helpful tool in adjuvant treatment decisions in stage II and III colon cancer

    Programmed death ligand 1 (PD-L1) in colon cancer and its interaction with budding and tumor-infiltrating lymphocytes (TILs) as tumor-host antagonists

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    Purpose!#!To analyze the role of programmed death ligand 1 (PD-L1) immunohistochemisty in the context of tumor microenvironment in colon cancer (CC) with focus on the interaction between tumor budding and tumor-infiltrating lymphocytes (TILs) and to elucidate its potential value for immunooncologic treatment decisions.!##!Methods!#!Three hundred forty seven patients with CC, stages I to IV, were enrolled. PD-L1 immunohistochemistry was performed using two different antibodies (clone 22C3 pharmDx, Agilent and clone QR1, Quartett). Tumor proportion score (TPS) as well as immune cell score (IC) was assessed. Budding and TILs were assessed according to the criteria of the International Tumor Budding Consensus Conference (ITBCC) and International TILs Working Group (ITWG). Correlation analyses as well as survival analyses were performed.!##!Results!#!PD-L1 positivity significantly correlated with TILs > 5% and MMR deficiency, and PD-L1-positive cases (overall and IC) showed significantly longer overall survival (OS) with both antibodies.The parameters 'high grade,' 'right-sidedness,' and 'TILS > 5% regardless of MMR status' evolved as potential parameters for additional immunological treatment decisions. Additionally, TPS positivity correlated with low budding. More PD-L1-positive cases were seen in both high TIL groups. The low budding/high TIL group showed longer disease-free survival and longer OS in PD-L1-positive cases.!##!Conclusion!#!Overall, PD-L1 positivity correlated with markers of good prognosis. PD-L1 immunohistochemistry was able to identify parameters as additional potential candidates for immune therapy. Furthermore, it was able to stratify patients within the low budding/high TIL group with significant prognostic impact
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