The third helix of the homeodomain of the Antennapedia homeoprotein can translocate through the cell membrane into the nucleus and can be used as an intracellular vehicle for the delivery of oligopeptides and oligonucleotides. A 16-amino acid-long peptide fragment, called penetratin, is internalized by the cells in a specific, non-receptor-mediated manner. For a better understanding of the mechanism of the transfer, penetratin and two analogs were synthesized:The conformation of penetratin peptides 1-3 was examined in both extracellular matrix-mimetic and membrane-mimetic environments. (1)H-NMR and CD spectroscopic measurements were performed in mixtures of TFE/water with different ratios. Peptides 1-3 were labeled by reacting their N-terminal free amino group with fluorescein isothiocyanate (FITC). Membrane translocation of the labelled peptides was studied with cell cultures [WEHI 164 murine fibrosarcoma cells (WC/1); chicken fibroblast cells (CEC-32); chicken monocytic cells (HD-11); human fibroblast (SV 80) and human monocytic cells (MonoMac-6)]. Confocal laser scanning microscopy and flow cytometry assay were used to study membrane translocation. Amphiphilicity was calculated for each peptide. In our experiments all the penetratin peptides penetrated into the cells. Helical conformation and membrane translocation ability showed little correlation: substitution of the two Trp with Phe increased the stability of helical conformation but decreased membrane translocation activity. The results of fluorescence microscopy and flow cytometry show that penetratin can be translocated into the cells by two mechanisms: endocytosis and direct transport through the cell membrane.

Introduction. A retrospective analysis of the relation between the presence of casting-type calcifications on the mammogram and the prognosis of breast cancer was performed. Materials and methods. The mammographic tumor features and other characteristics (invasive tumor size, histological tumor type, grade, nodal, hormone receptor and HER2 status, presence of lymphovascular invasion) of 55 high-risk breast cancers were studied. Results. After a median follow-up time of 29.1 months, the median relapse-free survival and overall survival times among breast cancer patients with tumors associated with casting calcifications were 26.6 and 29.6 months, respectively. The corresponding parameters among patients with tumors not accompanied by casting calcifications were 54.4 and 58.5 months, respectively. Significant associations were found between the presence of casting calcifications and the risks of relapse (HR03.048, 95% CI: 1.116Á8.323, p00.030) or death (HR03.504, 95% CI: 1.074Á11.427, p00.038). Positive associations were found between casting calcifications and ER/PR negativity (p00.015 and p 00.003, respectively) and HER2 overexpression (p00.019). Discussion. Our findings support the theory that breast tumors associated with casting-type calcifications at mammography comprise a disease entity which exhibits significantly more aggressive behavior and a poorer outcome than do cancers with other mammographic tumor features.

As endocytic uptake of the Antennapedia homeodomain-derived penetratin peptide (RQIKIWFQNRRMKWKK) is finally being revealed, some of the early views about penetratin need to be reconsidered. Endocytic uptake seems to contradict the indispensability of tryptophans and also the minimum length of 16 amino acid residues for efficient internalization. To revise the membrane translocation of penetratin, two penetratin analogs were designed and synthesized: a peptide in which tryptophans were replaced by phenylalanines (Phe(6,14)-penetratin, RQIKIFFQNRRMKFKK) and a shortened analog (dodeca-penetratin, RQIKIWF-R-KWKK) made up of only 12 residues. The peptides were fluorescently labeled and applied to live, unfixed cells from various lines. Cellular uptake was analysed by confocal microscopy and flow cytometry. Low temperature or ATP-depletion blocked the intracellular entry of all three penetratin peptides. A decrease in membrane fluidity or cholesterol depletion with methyl-beta-cyclodextrin greatly inhibited peptide uptake, showing the involvement of cholesterol-rich lipid rafts in internalization. Exogenous heparan sulfate also diminished the internalization of penetratin and its derivatives, reflecting the paramount importance of electrostatic interactions with polyanionic cell-surface proteoglycans. The beneficial presence of tryptophans is supported by observations on the decreased cellular uptake of Phe(6, 14)-penetratin. The maintained translocational efficiency of dodeca-penetratin demonstrates that a thorough understanding of penetratin internalization can yield new penetratin analogs with unaltered translocational abilities. This study provides evidence on the energy-dependent and lipid raft-mediated endocytic uptake of penetratin and highlights the necessity of revealing those pathways that cationic cell-penetrating peptides employ to enter live cells.

We consider this simple clinical tool appropriate for assisting individual positioning aiming at maximum heart protection during left breast irradiation.

Background Studying the clinical utility of deep-inspirational breath-hold (DIBH) in left breast cancer radiotherapy (RT) was aimed at focusing on dosimetry and feasibility aspects. Methods In this prospective trial all enrolled patients went through planning CT in supine position under both DIBH and free breathing (FB); in whole breast irradiation (WBI) cases prone CT was also taken. In 3-dimensional conformal radiotherapy (3DCRT) plans heart, left anterior descending coronary artery (LAD), ipsilateral lung and contralateral breast doses were analyzed. The acceptance of DIBH technique as reported by the patients and the staff was analyzed; post-RT side-effects including radiation lung changes (visual scores and lung density measurements) were collected. Results Among 130 enrolled patients 26 were not suitable for the technique while in 16, heart or LAD dose constraints were not met in the DIBH plans. Among 54 and 34 patients receiving WBI and postmastectomy/nodal RT, respectively with DIBH, mean heart dose (MHD) was reduced to < 50%, the heart V25 Gy to < 20%, the LAD mean dose to < 40% and the LAD maximum dose to about 50% as compared to that under FB; the magnitude of benefit was related to the relative increase of the ipsilateral lung volume at DIBH. Nevertheless, heart and LAD dose differences (DIBH vs. FB) individually varied. Among the WBI cases at least one heart/LAD dose parameter was more favorable in the prone or in the supine FB plan in 15 and 4 cases, respectively; differences were numerically small. All DIBH patients completed the RT, inter-fraction repositioning accuracy and radiation side-effects were similar to that of other breast RT techniques. Both the patients and radiographers were satisfied with the technique. Conclusions DIBH is an excellent heart sparing technique in breast RT, but about one-third of the patients do not benefit from that otherwise laborious procedure or benefit less than from an alternative method. Trial registration: retrospectively registered under ISRCTN14360721 (February 12, 2021)

No abstract

The benefit of reduced radiation heart exposure in the prone vs. supine position, individually differs according to the anatomical features of the patient (Varga Z, Int J Radiat Oncol Biol Phys. 2009;75:94-110). Preferable positioning may be predicted by a statistical model. This validated calculator using the patient's body mass index (BMI), the median distance of the anterior surface of the left coronary artery (LAD) from the chest wall (Dmed) and the heart area (Aheart) included in the radiation field in a single CT scan at the middle of the heart (median plane, Pmed) provides quantitative estimates of the dose differences to the LAD or heart in the two positions (Varga Z, Acta Oncol. 2014;53:58-64). In this prospective cohort study, the goal was to develop a reliable method to collect data for the calculator without acquiring a full series of CT scans in both positions. The study was approved by the Institutional Review Board of the University of Szeged, and all the enrolled patients gave their written informed consent to participation. Eligible patients needed postoperative left breast radiotherapy. In 100 patients, a single CT slice image representing the middle of the heart (reference plane, Pref) was acquired by using the AP scout view in the supine position for the selection of the transversal plane appropriate for the measurements of Dmed and Aheart. Thereafter, CT series were acquired in both positions, and analyses were performed on 1. the conformance of the Pref with Pmed , 2. the effect of plane miss on the choice of preferable position. 3. Finally the sensitivity and specificity of this simple clinical method was reevaluated based on the dosimetry data (mean LAD dose, V25Gy heart) obtained using the topogram for selecting the position. In 55 cases, Pref was the same as Pmed, while in 27 and 18 cases, Pref and Pmed differed by 2 or more planes, respectively. No difference was found between the values of Dmed or Aheart asmeasured in Pref vs. Pmed, independently whether Pref was identified correctly or not.The suggestion on treatment position per Pref measurements, was correct in 85 cases, was ambiguous in 8 cases and incorrect in 7 cases. Sensitivity of the calculator based on Pref measurements was 90% (both mean LAD dose and V25Gy heart), while specificity was 72% (mean LAD dose) and 68% (V25Gy heart). The simple clinical method was tested in additional 60 left breast radiotherapy cases, by taking a topogram and a CT series in the suggested position only. Mean LAD dose (mean [CI95%] prone vs. supine: 6.5 [5.7-7.3] Gy vs. 7.5 [5.6-9.5] Gy) and V25Gy heart (mean [CI95%] prone vs. supine: 0.87 [0.67-1.11] % vs. 1.13 [0.55-1.71]%) well corresponded to the institutional dose constraints based on dosimetry data achieved with individual positioning in &gt;300 patients with left-sided breast cancer. We consider this simple clinical tool appropriate for assisting individual positioning aiming at maximum heart protection during left breast irradiation. *Supported by the VKSZ 12-1-2013-0012 project. Citation Format: Kahán Z, Gaál S, Cserháti A, Rárosi F, Boda K, Varga Z. Prone vs. supine positioning for optimizing radiation heart exposure during left breast radiotherapy: A simple clinical tool for prediction* [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 P1-10-11.

A dohánykereskedelem és a dohányfogyasztás szabályozása, s az esetleges állami monopolizálása szinte minden államban fontos, különféle társadalmi, gazdasági és pénzügyi szempontok miatt. E terület szabályozása hazánkban 2010-et követően vált különösen fontos területé, mely változási folyamatot egy korábbi tanulmányomban elemeztem. 2 Jelen írásomban a dohánykereskedelem monopolizálásának témáját tovább fűzve, a dohányzás és a dohánytermékek fogyasztásának szabályozását kívánom elemezni, különös tekintettel más országok szabályozására. A nemzetközi vizsgálódás keretében először az Európai Unió, majd az Amerikai Egyesül Államok, s végül Oroszország szabályozását vizsgálom meg.