A uniform residual tumor (R) classification: integration of the R classification and the circumferential margin status.

Contains fulltext : 79663.pdf (publisher's version ) (Closed access)BACKGROUND: Since the introduction of the TNM residual tumor (R) classification, the involvement of resection margins has been defined either as a microscopic (R1) or a macroscopic (R2) demonstration of tumor directly at the resection margin ("tumor transected"). METHODS: The recognition of the importance of the circumferential resection margin (CRM) in patients with rectal cancer patients raises the need for an alternative definition of resection margin involvement, namely, the importance of delineating tumor with a minimal distance from the CRM of <or=1 mm (CRM-positive) from tumor directly at the resection margin. The different use of both definitions of resection margin involvement prevents valid comparisons between reports on treatment results. RESULTS: To avoid confusion by different definitions, the authors proposed including the minimal distance between tumor and resection margin into the current R classification. CONCLUSIONS: By using the proposed expanded classification, comparisons of new data with previous publications will be possible

MOESM1 of Pho dynamically interacts with Spt5 to facilitate transcriptional switches at the hsp70 locus

Additional file 1: Figure S1. Schematic representation of the proteins involved in the silencing, activation and re-silencing of the hsp70 locus. a At optimal growth temperature, Pho, a DNA-binding PcG member, binds to promoter region of the hsp70 locus. Pho interacts with dSfmbt, which together form a recruitment platform for PRC1 to the hsp70 locus. In addition, RNA polymerase II is maintained in the paused state by NELF and Spt5, which act as pausing factors. Upon heat shock, HSF, along with P-TEFb, is recruited to chromatin and releases RNA polymerase II from the paused state. P-TEFb modifies Spt5 and converts into an elongation factor. It also modifies the CTD of RNA polymerase II to enable productive elongation. However, upon removal of the heat shock stimulus, the locus should eventually return to its paused state. Thus, hsp70 is an ideal model gene to study the eviction and recruitment of PRC1 upon activation and re-silencing, respectively. The colour code for the protein names is as follows: silencing in red, pausing factors in orange and activators in green