117,488 research outputs found
PTEN immunohistochemistry is a predictor of mismatch repair status in breast cancer
No full textAbstract
Phosphatase and tensin homolog (PTEN), a potent downregulator of the PI3K-Akt pathway, has been shown to mediate the interaction between poly (ADP-ribose) polymerases (PARPs) and the mismatch repair (MMR) complex in endometrial and ovarian cancer. Drugs inhibiting PARPs (iPARPs) are currently considered promising therapeutic tools in a subset of PTEN-defective tumors. Regrettably, the frequency and significance of MMR alterations in breast cancer is debated, and their relationship with PTEN status has not been investigated in the breast. Furthermore, many of the studies on the DNA damage response and its therapeutic implications in breast cancer focus on inherited syndromes (e.g. Lynch syndrome and hereditary breast-ovarian cancer syndrome).
Aims: We sought to explore the interplay between PTEN and the MMR system and to define whether PTEN immunohistochemistry (IHC) is a predictor of MMR proficiency in non-familial breast cancers.
Methods: 373 cases of non-familial breast cancers, including a representative number of no special (n=295) and special types (n=78), carefully characterized from clinical and pathological standpoints, were reviewed and used to construct 14 tissue microarrays (TMAs). For each case, a mean of 4.5 tumor tissue cores (range 3 to 6 cores) was sampled, incorporating distinct topographic areas of the tumor, as well as matched non-neoplastic breast tissue. Taken together, 1876 spots were generated. Each TMA was subjected to IHC for PTEN and the DNA MMR proteins MLH1, MSH2, MSH6 and PMS2. In order to minimize human-related biases, each stained slide was digitalized and two pathologists blindly analyzed each tumor spot using a dedicated software able to segment and randomize TMA cores. The pattern of expression was therefore annotated manually on a digital database using a specific add-on module to reconstruct the original topography.
Results: According to clinicopathologic surrogate definition of intrinsic subtypes, PTEN protein loss or heterogeneous expression was more frequent in estrogen receptor negative cancers. Furthermore, 100% of the MMR-proficient luminal B-like (HER2+) and triple-negative breast cancers displayed strong and diffuse homogeneous PTEN expression, while PTEN-positive status identified MMR-proficient luminal A-like and luminal B (HER2-) like tumors with accuracy rates of 89.3% and 92.7%, respectively (p=0.001, Fisher's exact test).
Conclusions: The present study is the first to investigate PTEN protein loss in a large set of non-familial breast carcinomas based on their DNA MMR status by IHC. Here, we demonstrated that PTEN strong and homogeneous expression by IHC is able to capture the vast majority of MMR-proficient non-familial breast cancers. Our findings broaden the understanding of the biology underpinning these tumors, suggesting that PTEN is likely play a role in the development of MMR alterations. Given that PTEN-defective breast cancers have the propensity to develop additional somatic alterations in the MMR system, our results suggest that IHC for PTEN and MMR proteins may be emplyed as an ancillary study to define new subclasses of sporadic breast cancers potentially eligible for iPARPs therapies.
Citation Format: Fusco N, Gambini D, Runza L, Lopez G, Ercoli G, Despini L, Bosari S. PTEN immunohistochemistry is a predictor of mismatch repair status in breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P5-06-07.</jats:p
Approaching the histodynamics of celiac disease in modern times : the need of going beyond the dogmas
No full text
Paratesticular Extramedullary Hematopoiesis in Children
No full textContext.—: Extramedullary hematopoiesis (EMH) is an uncommon occurrence, usually associated with hematologic disorders, but it rarely presents as an isolated finding. Objective.—: To determine the frequency, immunomorphologic features, and clinicopathologic background of EMH in orchiectomies from pediatric patients. Design.—: All orchiectomy specimens removed from children from 2008 to 2020 in our institution were retrospectively reviewed. Biopsies and neoplasias were excluded. The EMH diagnosis was rendered when hematopoietic cell precursors were present. Immunohistochemical stainings were performed to characterize the hematopoietic components. Results.—: Seventy-nine orchiectomies from 77 children (mean age, 5 years; range, 0-17 years) were included in our study. Forty-three patients (55.8%) underwent surgery for testicular atrophy, 30 (39.0%) for torsion, and 4 (5.2%) for intersex conditions. EMH was identified in 6 of 79 orchiectomies (7.6%), all performed for testicular torsion. All patients but one were newborns, and the remaining patient was 15 years old. No patient had evidence of a hematologic disorder. All EMH foci were in a background of reactive changes with a variable extension, either in the epididymis (4 cases) or in the deferens duct (2 cases). Immunostaining confirmed an association of myeloid (myeloperoxidase+) and erythroid precursors (E-cadherin+) in all 6 cases. One case also presented rare megakaryocytes, and one showed benign TdT+ B-cell precursors. Conclusions.—: To our knowledge, this is the first study that demonstrates EMH as a common finding in orchiectomy samples, especially from newborns. Despite the lack of pathologic potential, it is important to recognize EMH in order to avoid misdiagnosis
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Are dental implants the first option in case of severely compromised teeth associated with radicular cyst? A critical case report
No full textBackground Nowadays, dental implants are frequently used to replace teeth judged as hopeless, even if other treatments should be primarily considered to save them. The reason lies in the fact that extracting a tooth and placing an implant is erroneously considered by many to be easier, faster, and more predictable. This trend of reduced willingness to save compromised teeth is strengthened by the concomitant presence of periapical tooth pathologies, such as radicular cyst. in such cases, affected teeth are condemned prematurely in favour of implant rehabilitations. This case report aims to illustrate a case where compromised teeth were maintained following the enucleation of a radicular cyst. Case report after enucleation of the radicular cyst, retrograde endodontic treatment of the affected teeth was performed. The residual bone defect was then treated with guided bone regeneration to assist and promote healing and improve the prognosis of adjacent teeth. Conclusion The technique proved to be effective and, most importantly, biologically friendly
Profilo di accettabilità dell'angiografia coronarica non invasiva mediante TC multistrato: per una medicina dalla parte del paziente.
No full textSquare Dancing with the Stars to Enhance Dynamic Hirschman Linkages?
No full textIn this Presidential Address, the author takes the reader on a reconnaissance of his life and time as a regional scientist. He points out scenery he found scintillating along the way, hoping that some may pick up the banner and chew on a few of the ideas for a while. He suggests a revisit to Albert O. Hirschman’s notion of key sectors and more empirical analysis related to Marcus Berliant’s and Masahisa Fujita’s notion of knowledge creation and transfer.Presidential Address, San Antonio, Texas, March 29, 2014 (53rd Meetings of the Southern Regional Science Association
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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