István Besznyák
Memorial Hospital of South Bend
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Featured researches published by István Besznyák.
Pathology & Oncology Research | 2012
Anna-Mária Tőkés; Attila Marcell Szász; Éva Juhász; Zsuzsa Schaff; László Harsányi; István Arthur Molnár; Zsolt Baranyai; István Besznyák; Attila Zaránd; Ferenc Salamon; Janina Kulka
In the past few decades an enormous amount of data became known to clarify the molecular composition and architecture of tight junctions (TJs). Despite the efforts, the expression and function of several TJ genes and proteins in breast carcinoma are still not known and some of the data are contradictory. The expression of forty-four TJ associated genes was examined at mRNA level in eighteen invasive ductal breast carcinoma samples and corresponding normal breast tissues by using low density array PCR. Expressions of claudins (CLDNs) 5, 10, 16, 17, and 18, and ZO-1, ZO-2 were evaluated by immunohistochemistry as well. Using immunohistochemical phenotype as a surrogate for the genetic subtype, 11 luminal A, 3 luminal B, 3 triple negative and one HER2+ cases were included. Ten genes were significantly downregulated in tumors compared with normal breast tissues (CLDNs 5, 10, 16, 18, 19, CTNNAL1, JAM-B, ZO-1, ZO-2 and PARD3), whereas one gene (CLDN17) was significantly up-regulated in tumors when compared with normal breast. At protein level CLDNs 5, 10, 16, 18, ZO-1 and ZO-2 were downregulated in tumors as compared with normal breast tissue. CLDN17 showed variable expression in tumor tissues in comparison to normal breast. In the single HER2+ tumor when compared with the other subtypes CLDNs 5, 16, 17, 18, CTNNAL1, JAM-B, ZO-1, ZO-2 and PARD3 genes were found to be upregulated. We found altered TJ genes and proteins whose expression has not yet been associated with breast carcinoma. Our findings show a tendency of TJ genes and proteins to be downregulated in breast cancer. Further studies are necessary to examine whether the downregulation of the above mentioned TJ associated genes and proteins may contribute to the malignant progression of invasive ductal breast carcinomas.
Pathology & Oncology Research | 1995
Zsolt Orosz; István Besznyák
Inflammatory pseudotumors have been recognized in many parts of the body. A case of a diffuse variant which involved the testis, the epididymis and the spermatic cord is described. The patient had enlarged left testis for several months. Clinically, the lesion mimicred cancer. Histologically, the lesion contained hyalinized fibrous tissue with spindle cells, plasma cells and lymphocytes. Gradual involvement of vascular channels by the cellular elements of inflammatory pseudotumor was observed. Results of immunohistochemical studies showed a myofibroblast differentiation in the majority of spindle cells: intense antibody staining for smooth muscle actin, muscle specific actin, and vimentin. The ultrastructural findings, intracytoplasmic filaments with dense bodies, were also consistent with the myofibroblastic nature of these cells. The histiocyte differentiation of spindle cells is questionable in our case, because only scattered histiocyte-like cells showed positivity with the KP-1 (CD-3) antibody.
Journal of Histochemistry and Cytochemistry | 2012
Tímea Váradi; Tamás Mersich; Päivi Auvinen; Raija Tammi; Markku Tammi; Ferenc Salamon; István Besznyák; Ferenc Jakab; Zsolt Baranyai; János Szöllősi; Péter Nagy
Although trastuzumab is an efficient drug, primary and acquired resistance is a challenging problem. The authors have previously shown in mouse xenograft experiments that masking ErbB2 by hyaluronan leads to diminished binding of the antibody and consequent resistance. In the current work, they correlated trastuzumab binding with the pericellular density of hyaluronan in ErbB2-overexpressing human breast cancer samples. A method for quantifying the relative binding of trastuzumab was developed involving constant and low-frequency background subtraction, segmenting the image to membrane and background pixels followed by evaluation of trastuzumab fluorescence, normalized with the expression level of ErbB2, only in the membrane. The normalized binding of trastuzumab showed a negative correlation with the pericellular density of hyaluronan (r = −0.52) with the effect being the most pronounced in the extreme cases (i.e., low and high hyaluronan densities predicted strong and weak binding of trastuzumab, respectively). Removal of hyaluronan by hyaluronidase digestion unmasked the trastuzumab binding epitope of ErbB2 demonstrated by a significantly increased normalized binding of the antibody. The results show that the accumulation of pericellular hyaluronan plays a crucial role in masking ErbB2.
Diagnostic Pathology | 2015
Tamás Micsik; András Lőrincz; Tamás Mersich; Zsolt Baranyai; István Besznyák; Kristóf Dede; Attila Zaránd; Ferenc Jakab; László Krecsák Szöllösi; György Kéri; Richard Schwab; István Peták
BackgroundThe ATP-Binding Cassette (ABC)-transporter MultiDrug Resistance Protein 1 (MDR1) and Multidrug Resistance Related Protein 1 (MRP1) are expressed on the surface of enterocytes, which has led to the belief that these high capacity transporters are responsible for modulating chemosensitvity of colorectal cancer. Several immunohistochemistry and reverse transcription polymerase chain reaction (RT-PCR) studies have provided controversial results in regards to the expression levels of these two ABC-transporters in colorectal cancer. Our study was designed to determine the yet uninvestigated functional activity of MDR1 and MRP1 transporters in normal human enterocytes compared to colorectal cancer cells from surgical biopsies.Methods100 colorectal cancer and 28 adjacent healthy mucosa samples were obtained by intraoperative surgical sampling. Activity of MDR1 and MRP1 of viable epithelial and cancer cells were determined separately with the modified calcein-assay for multidrug resistance activity and sufficient data of 73 cancer and 11 healthy mucosa was analyzed statistically.ResultsSignificantly decreased mean MDR1 activity was found in primary colorectal cancer samples compared to normal mucosa, while mean MRP1 activity showed no significant change. Functional activity was not affected by gender, age, stage or grade and localization of the tumor.ConclusionWe found lower MDR activity in cancer cells versus adjacent, apparently, healthy control tissue, thus, contrary to general belief, MDR activity seems not to play a major role in primary drug resistance, but might rather explain preferential/selective activity of Irinotecan and/or Oxaliplatin. Still, this picture might be more complex since chemotherapy by itself might alter MDR activity, and furthermore, today limited data is available about MDR activity of cancer stem cells in colorectal cancers.Virtual slidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1675739129145824
Orvosi Hetilap | 2008
Kristóf Dede; Tamás Mersich; Attila Zaránd; István Besznyák; Zsolt Baranyai; Bence Atkári; Ferenc Jakab
UNLABELLED Despite the fact that laparoscopic appendectomy was one of the first performed minimally invasive surgical procedures, the benefits and indications of its use are still controversial. METHODS Data of patients with the diagnosis of appendicitis operated either with laparoscopic (LA) or open (OA) appendectomy were collected and analyzed. PATIENTS This study involved 273 consecutive patients who had undergone appendectomy with the diagnosis of acute appendicitis at the Uzsoki Teaching Hospital, Department of Surgery between January 2005 and December 2007. 185 patients (68%) operated with the laparoscopic, 88 (32%) with the open technique, in the third year 89% of the cases underwent laparoscopic appendectomy. RESULTS The conversion rate was 27%, the reason of the conversion was the progression of the disease in 35 patients (70%) and technical in 15 cases (30%). The wound infection rate was 8% in the LA and 18% in the OA group ( p = 0.022). No significant difference was found in the reoperation rate and in the hospital readmission rate between the two groups. There was one insufficiency which was treated with conservative therapy. The hospital stay was significantly lower in the laparoscopic group ( p = 0.031). CONCLUSIONS This study demonstrated that laparoscopic appendectomy has significant advantages over open appendectomy. In our practice, laparoscopic appendectomy is the first choice of procedure in acute appendicitis.
Orvosi Hetilap | 2011
Zsolt Baranyai; Tamás Mersich; Kristóf Dede; István Besznyák; Attila Zaránd; Dániel Teknős; Péter Nagy; Ferenc Salamon; P. Nagy; Zsolt B. Nagy; Zsuzsanna Kótai; Marcell A. Szász; Lilla Lukács; Zoltan Szallasi; Valéria Jósa; Ferenc Jakab
The research group takes samples for molecular genetical examinations from tumors removed during operations within ischemic time interval. Samples are stored in liquid nitrogen. Clinical data of these patients are recorded in an informatics system developed by the group. Patients are followed in an out-patient clinic set up for this purpose not financed by the National Health Insurance Fund. Tissue samples and follow up data are used to cooperate with molecular genetical laboratories.
Pathology & Oncology Research | 1996
Marianna Sztán; István Besznyák; Tibor Kovács; J. Tóth; Irén Számel; Edith Olah
High incidence of loss of heterozygosity (LOH), affecting the 7q31–32 chromosome region in sporadic primary human breast carcinomas suggests the presence of a tumor suppressor gene in this region which seems relevant to the development of breast cancer. To further determine the possible role of this region in the pathogenesis of human primary breast cancer and association with survival, LOH analysis was performed on 52 primary breast cancer patients using a set of highly polymorphic microsatellite markers. Our panel contained twenty biopsy cases of unknown survival, nineteen cases with more than five years survival and fourteen cases with less than two years survival. Corresponding normal and tumor DNAs were analyzed by polymerase chain reaction (PCR). The data presented here demonstrate that all patients were informative at least at one locus and 20 (38%) out of 53 cases showed LOH at one or more loci on chromosome 7q31–32. Relatively high incidence of LOH (34%) was detected at the D7S522 microsatellite marker located near to the cMet proto-oncogene while lower frequencies were observed at D7S523 (19%) and D7S495 (17%) loci, supporting the existence of a putative tumor suppressor gene at the chromosome 7q31.1 region. Our results suggest that allelic imbalance on 7q may occur at an early stage of breast carcinogenesis, as no correlation was observed between allelic loss and clinico-pathological data.
Hungarian Journal of Surgery | 2017
Géza Papp; István Besznyák; Balázs Pörneczi; György Saftics; Attila Bursics
Absztrakt A laparoszkopos rectumsebeszet ma mar igazoltan alternativaja a hagyomanyos műteti technikanak. Ugyanakkor tovabbra is problemat jelent a kismedence melyenek vizualizalasa, a megfelelő distalis reszekcios sik biztositasa, a rectumcsonk egyetlen varrogeppel tortenő lezarasa es ezaltal a biztonsagos anastomosis keszitese. A laparoszkopos es a transanalis megkozelites kombinaciojakent jott letre a transanal total mesorectal excision (TaTME), amely technikaval a vilagon eddig korulbelul 500 műtetet vegeztek. A TaTME a mely rectumtumorok sebeszetenek fenti problemaira kinal megoldast. A transanalis rectumcsonk kepzese biztonsagos reszekcios sik kialakitasat teszi lehetőve, megoldja a distalis csonk zarasanak problemajat, kivalo latasi viszonyokat garantal pont a felulről legnehezebben megkozelithető teruleten, igy a kismedencei idegfonatok megkimeleseben is eredmeny varhato tőle. Esetbemutatasunk egy neoadjuvans kezelest kovetően jelentősen zsugorodott meretű, az anusnyilastol 5 cm magassagban azonos...
Orvosi Hetilap | 1991
Emil Farkas; István Besznyák; István Köves
Pathology & Oncology Research | 2013
K Dede; Mersich T; István Besznyák; Attila Zaránd; Ferenc Salamon; Zsolt Baranyai; Landherr L; Jakab F; Bursics A