61 research outputs found
Case Rep Oncol
The pretreatment detection of an activating mutation of EGFR is now routinely performed in metastatic nonsquamous non-small cell lung cancer (NSCLC). The therapeutic impact of such a detection is major, as patients with advanced NSCLC exhibiting a mutation of exon 19 or 21 will benefit from EGFR-tyrosine kinase inhibitors (TKI). The presence of an EGFR resistance mutation, such as T790M in EGFR-TKI-naïve patients, is seldom looked for and is related either to a germinal mutation or to somatically mutated subclones. It has a negative predictive impact. We present the case of a patient with a lung papillary adenocarcinoma and miliary intrapulmonary metastases whose tumor displays a somatic complex heterozygous EGFR mutation, combining L858R (exon 21) and a primary resistance mutation T790M (exon 20), both detected by direct sequencing
Irradiation-Induced Deinococcus radiodurans Genome Fragmentation Triggers Transposition of a Single Resident Insertion Sequence
Stress-induced transposition is an attractive notion since it is potentially important in creating diversity to facilitate adaptation of the host to severe environmental conditions. One common major stress is radiation-induced DNA damage. Deinococcus radiodurans has an exceptional ability to withstand the lethal effects of DNA–damaging agents (ionizing radiation, UV light, and desiccation). High radiation levels result in genome fragmentation and reassembly in a process which generates significant amounts of single-stranded DNA. This capacity of D. radiodurans to withstand irradiation raises important questions concerning its response to radiation-induced mutagenic lesions. A recent study analyzed the mutational profile in the thyA gene following irradiation. The majority of thyA mutants resulted from transposition of one particular Insertion Sequence (IS), ISDra2, of the many different ISs in the D. radiodurans genome. ISDra2 is a member of a newly recognised class of ISs, the IS200/IS605 family of insertion sequences
Connexin and pannexin (hemi) channels in the liver
The liver was among the first organs in which connexin proteins have been identified. Hepatocytes harbor connexin32 and connexin26, while non-parenchymal liver cells typically express connexin43. Connexins give rise to hemichannels, which dock with counterparts on adjacent cells to form gap junctions. Both hemichannels and gap junctions provide pathways for communication, via paracrine signaling or direct intercellular coupling, respectively. Over the years, hepatocellular gap junctions have been shown to regulate a number of liver-specific functions and to drive liver cell growth. In the last few years, it has become clear that connexin hemichannels are involved in liver cell death, particularly in hepatocyte apoptosis. This also holds true for hemichannels composed of pannexin1, a connexin-like protein recently identified in the liver. Moreover, pannexin1 hemichannels are key players in the regulation of hepatic inflammatory processes. The current paper provides a concise overview of the features of connexins, pannexins and their channels in the liver.This work was financially supported by the grants of the Agency for Innovation by Science and Technology in Flanders (IWT), the University Hospital of the Vrije Universiteit Brussel-Belgium (Willy Gepts Fonds UZ-VUB), the Fund for Scientific Research - Flanders (FWO grants G009514N and G010214N), the European Research Council (ERC Starting Grant 335476), the University of Sao Paulo-Brazil (USP) and the Foundation for Research Support of the State of Sao Paulo (FAPESP SPEC grant 2013/50420-6)
E-cadherin in canine mast cell tumors: Decreased expression and altered subcellular localization in Grade 3 tumors
Mast cell tumors (MCTs) are the most frequent round cell tumors in dogs and comprise approximately 21% of all canine cutaneous tumors. MCTs are highly invasive and metastatic corresponding to the histological grade. E-cadherin is an adhesion molecule expressed in epithelial cells and although it is an epithelial cellular marker, studies have shown expression of E-cadherin in canine round cell tumors. To better characterize the expression pattern of E-cadherin in several different histological grades of MCTs in dogs, the expression and localization of the adhesion molecule was investigated using immunohistochemistry. For this purpose, 18 cutaneous MCTs were classified into three histological grades, 1, 2 or 3. Clinical history and follow-up data were available for all of the dogs. Cytoplasmic and nuclear expressions of E-cadherin in all three types of tumors were verified by immunostaining using two different antibodies. There was decreased E-cadherin expression in the more aggressive MCTs (Grade 3), suggesting an association between E-cadherin and tumor aggressiveness. Additionally, the loss of E-cadherin expression in either the cytoplasm or nucleus in more aggressive and undifferentiated tumor types confirmed the importance of cellular adhesion in tumor behavior. (C) 2012 Published by Elsevier Ltd.Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [2009/12827-1]; [2010/08523-4
A Major Role of the RecFOR Pathway in DNA Double-Strand-Break Repair through ESDSA in Deinococcus radiodurans
In Deinococcus radiodurans, the extreme resistance to DNA–shattering treatments such as ionizing radiation or desiccation is correlated with its ability to reconstruct a functional genome from hundreds of chromosomal fragments. The rapid reconstitution of an intact genome is thought to occur through an extended synthesis-dependent strand annealing process (ESDSA) followed by DNA recombination. Here, we investigated the role of key components of the RecF pathway in ESDSA in this organism naturally devoid of RecB and RecC proteins. We demonstrate that inactivation of RecJ exonuclease results in cell lethality, indicating that this protein plays a key role in genome maintenance. Cells devoid of RecF, RecO, or RecR proteins also display greatly impaired growth and an important lethal sectoring as bacteria devoid of RecA protein. Other aspects of the phenotype of recFOR knock-out mutants paralleled that of a ΔrecA mutant: ΔrecFOR mutants are extremely radiosensitive and show a slow assembly of radiation-induced chromosomal fragments, not accompanied by DNA synthesis, and reduced DNA degradation. Cells devoid of RecQ, the major helicase implicated in repair through the RecF pathway in E. coli, are resistant to γ-irradiation and have a wild-type DNA repair capacity as also shown for cells devoid of the RecD helicase; in contrast, ΔuvrD mutants show a markedly decreased radioresistance, an increased latent period in the kinetics of DNA double-strand-break repair, and a slow rate of fragment assembly correlated with a slow rate of DNA synthesis. Combining RecQ or RecD deficiency with UvrD deficiency did not significantly accentuate the phenotype of ΔuvrD mutants. In conclusion, RecFOR proteins are essential for DNA double-strand-break repair through ESDSA whereas RecJ protein is essential for cell viability and UvrD helicase might be involved in the processing of double stranded DNA ends and/or in the DNA synthesis step of ESDSA
Inhibiteurs du check-point immunitaire en néo-adjuvant dans les cancers bronchiques non à petites cellules localisés : Essai clinique de phase II IFCT-1601 IoNESCO
International audienceBackgroundProgrammed cell death-ligand 1 (PD-L1) is a checkpoint receptor that facilitates immune evasion by tumor cells, through interaction with programmed cell death-1 (PD-1), a receptor expressed by T-cells. Durvalumab is an anti-PD-L1 monoclonal antibody that blocks PD-L1 interaction with PD-1 on T-cells, countering the tumor's immune-evading tactics. Phase I/II studies demonstrated durable responses and manageable tolerability in heavily pre-treated patients with non-small cell lung cancer (NSCLC).MethodsThis phase II study is designed to administrate three durvalumab IV infusions (10 mg/kg at day 1, 15, 29) before surgery, to patients with pathologically confirmed NSCLC, clinical stage IB (> 4 cm) or stage II, ≥ 18 years of age, WHO performans status 0–1, without selection on PD-L1 expression. Preoperative chemotherapy and radiation therapy are not permitted. The primary objective is feasibility of complete surgical resection. Major pathological response on surgical tissue, defined as 10% or less remaining tumor cells, will be a secondary objective. Additional secondary objectives include tolerance, adverse effects, delay between start of treatment and surgery, response rate (RECIST 1.1), metabolic response rate, postoperative adverse events, disease-free survival and overall survival. A rate of complete resection 4 cm) ou II. La chimiothérapie et la radiothérapie préopératoire ne sont pas permises. L’objectif principal est la faisabilité d’une résection chirurgicale complète. Un taux de résection complète < 85 % (P0) est considéré comme inacceptable. Avec une hypothèse P1 de 95 %, une puissance de 90 % et un risque alpha de 5 %, 81 patients sont nécessaires. La réponse histologique majeure (≤ 10 % de cellules tumorales résiduelles sur la pièce opératoire) est un objectif secondaire. Les autres objectifs sont le délai entre traitement et chirurgie, les taux de réponse radiologique et métabolique, les évènements indésirables, la survie sans récidive et globale.Résultats attendusL’immunothérapie néo-adjuvante est faisable et pourrait améliorer la survie des CBNPC de stade précoce
Supplementary Material for: Diagnosis of Jejunal Metastases from Lung Cancer Using Capsule Endoscopy
Gastrointestinal metastases from lung cancer are rare and usually asymptomatic. We report a case of small bowel metastases from primary lung cancer revealed by abdominal pain and severe recurrent anaemia. The diagnosis was obtained with capsule endoscopy. This non-invasive procedure thus represents a valuable method contributing to a rapid and detailed diagnosis while reducing underdiagnosis, and it should thus be considered for lung cancer patients complaining of abdominal symptoms, which may indeed be related to gastrointestinal metastases
- …