Proteomic Interactome of C. elegans Mediator Complex Subunit 28 (MDT-28) Reveals Predominant Association with a Restricted Set of Core Mediator Subunits and an Affinity to Additional Structural and Enzymatic Proteins.

Transcription factors exert their regulatory potential on RNA polymerase II machinery through a multiprotein complex called Mediator complex or Mediator. The Mediator complex integrates regulatory signals from cell regulatory cascades with the regulation by transcription factors. The Mediator complex consists of 25 subunits in Saccharomyces cerevisiae and 30 or more subunits in multicellular eukaryotes. Mediator subunit 28 (MED28), along with MED30, MED23, MED25 and MED26, belong to presumably evolutionarily new subunits that seem to be absent in unicellular eukaryotes and are likely to have evolved together with multicellularity and cell differentiation. Previously, we have shown that an originally uncharacterized predicted gene, F28F8.5, is the true MED28 orthologue in Caenorhabditis elegans (mdt-28) and showed that it is involved in a spectrum of developmental processes. Here, we studied the proteomic interactome of MDT-28 edited as GFP::MDT-28 using Crispr/Cas9 technology or MDT-28::GFP expressed from extrachromosomal arrays in transgenic C. elegans exploiting the GFPTRAP system and mass spectrometry. The results show that MDT-28 associates with the Head module subunits MDT-6, MDT-8, MDT-11, MDT-17, MDT- 20, MDT-22, and MDT-30 and the Middle module subunit MDT-14. The analyses also identified additional proteins as preferential MDT-28 interactants, including chromatin-organizing proteins, structural proteins and enzymes. The results provide evidence for MDT-28 engagement in the Mediator Head module and support the possibility of physical (direct or indirect) interaction of MDT-28 with additional proteins, reflecting the transcription-regulating potential of primarily structural and enzymatic proteins at the level of the Mediator complex.

[Colorectal cancer in senior patients - are we doing it well?] / Kolorektální karcinom u senioru - deláme to dobre?

INTRODUCTION: Geriatric patients form a significant part of patients with colorectal cancer and their numbers will probably continue to increase. Analysis of the quality of care provided to seniors and the results from their treatment are currently gaining more attention. The aim of this study was to compare how often standard oncological therapy is administered to seniors with colorectal cancer and to compare their results with younger patients along with complications of the therapy. METHOD: A retrospective analysis of data from 170 patients with the diagnosis of colorectal cancer undergoing an elective curative surgical procedure in 2014 and 2015 was performed. Patients were divided into three groups according to their age (<60 years old, 6079 years old, 80 years old). We compared their ASA score, tumor stage (IIV), tumor localization (colon, rectum), incidence of serious complications grade 35 on the Clavien-Dindo scale and adherence to standard oncological treatment in the individual age groups. RESULTS: Patients 80 years and older had significantly higher ASA scores (p=0.0001) and significantly higher stages of tumors according to TNM-7 classification (p=0.0413) in comparison to younger patients. Differences in numbers of serious complications (<60 years - 14%, 6079 years - 13%, 80 years 30%, p=0.1499) did not reach statistical significance. Seniors underwent modified oncological treatment (<60 years - 6%, 6079 years - 9%, 80 years 30%, p = 0.0095) significantly more frequently in comparison to younger age groups. CONCLUSION: The application of standard multimodal oncological treatment is possible even in selected patients that are 80 years and older. Implementation of more reliable methods to objectively predict postoperative complications can become a tool to modify the treatment and improve the results of surgical care in elderly patients.Key words: geriatric patients - oncosurgery complex geriatric assessment colorectal cancer.

[Cholecystostomy--an obsolete or relevant treatment?]. / Cholecystostomie--obsoletní, nebo aktuální resení?

INTRODUCTION: Percutaneous cholecystostomy is considered to be an emergency treatment option when conservative treatment of acute cholecystitis fails in elderly and critically ill patients. The question is: to what extent is this technique still up-to-date or obsolete. METHODS: We retrospectively reviewed data of patients who underwent a computer tomography (CT) guided percutaneous cholecystostomy between 1/20101/2015. We analyzed the patient data, the success rate, complications of the procedure, short- and long-term outcomes. RESULTS: 30 patients undergoing CT-guided percutaneous cholecystostomy at the Department of Surgery, 2nd Faculty of Medicine, Charles University in Prague and Motol University Hospital during the study period were enrolled. The study group included 21 females (70%) and 9 males (30%) with mean age of 78 years (SD±12.3), median 82 years (range 3493 years). Percutaneous cholecystostomy was indicated for patients with severe cholecystitis/empyema of the gallbladder not responding to conservative therapy who were poor candidates for operative cholecystectomy. Of these, 23 patients (77%) were successfully treated with initial percutaneous cholecystostomy whereas 7 patients (23%) experienced treatment failure - one was subsequently successfully treated with repeated percutaneous cholecystostomy and six underwent emergency cholecystectomy. The mean length of stay was 16.5 days (SD±8.2), median 15 days (7-49 days). The total 30-day mortality was 17%, and indication-related mortality was 10%. Three patients (10%) had a recurrence. One patient required repeated percutaneous drainage, the second recovered on conservative treatment and the third patient underwent acute cholecystectomy. Only one patient (3%) underwent delayed laparoscopic cholecystectomy without complications. CONCLUSION: CT guided percutaneous cholecystostomy is a safe and effective therapeutic modality in patients unfit for surgery.

BIR-1, the homologue of human Survivin, regulates expression of developmentally active collagen genes in C. elegans.

BIR-1 and Survivin are highly conserved members of the inhibitor of apoptosis protein family that regulate cell division in nematodes and mammals and inhibit apoptosis in mammals. In the C. elegans genome, bir-1 is organized in an operon together with transcription and splicing cofactor CeSKIP (skp-1) and is highly expressed during embryogenesis as well as in non-dividing cells during larval development. Previously we have shown that BIR-1 regulates transcription and development and its loss-of-function phenotype overlaps with loss of function of CeSKIP and nuclear hormone receptor CHR3 (NHR-23). Here we searched for genes whose expression is affected by BIR-1 loss of function using whole-genome microarray experiments and identified several collagen genes as candidate targets of bir-1 inhibition in L1 larval stage. The decreased expression of selected collagen genes in bir-l-inhibited larvae was confirmed by quantitative RT-PCR. Next, we generated transgenic lines expressing bir-1 mRNA under a heat shock-regulated promoter and tested whether bir-1 overexpression has the potential to augment the expression of genes that showed decreased expression in worms treated with bir-1 RNAi. Overexpression of bir-1 resulted in a pronounced increase (2 to 5 times) of the expression of these genes. Our findings support the concept that BIR-1, a protein generally regarded as a mitotic factor, is involved in the regulation of transcription during normal development of C. elegans and has a strong ability to affect transcription of developmentally active genes if overexpressed.