The role of PCNA as a scaffold protein in cellular signaling is functionally conserved between yeast and humans

Proliferating cell nuclear antigen (PCNA), a member of the highly conserved DNA sliding clamp family, is an essential protein for cellular processes including DNA replication and repair. A large number of proteins from higher eukaryotes contain one of two PCNA‐interacting motifs: PCNA‐interacting protein box (PIP box) and AlkB homologue 2 PCNA‐interacting motif (APIM). APIM has been shown to be especially important during cellular stress. PIP box is known to be functionally conserved in yeast, and here, we show that this is also the case for APIM. Several of the 84 APIM‐containing yeast proteins are associated with cellular signaling as hub proteins, which are able to interact with a large number of other proteins. Cellular signaling is highly conserved throughout evolution, and we recently suggested a novel role for PCNA as a scaffold protein in cellular signaling in human cells. A cell‐penetrating peptide containing the APIM sequence increases the sensitivity toward the chemotherapeutic agent cisplatin in both yeast and human cells, and both yeast and human cells become hypersensitive when the Hog1/p38 MAPK pathway is blocked. These results suggest that the interactions between APIM‐containing signaling proteins and PCNA during the DNA damage response is evolutionary conserved between yeast and mammals and that PCNA has a role in cellular signaling also in yeast.publishedVersion© 2018 The Authors. Published by FEBS Press and John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution Licens

Changes in cellular signaling proteins in extracts from A549, H460, and U2OS cells treated with cisplatin or docetaxel

Cell extracts from A549, H460, and U2OS human cancer cell lines treated with cisplatin and docetaxel were analyzed by mass spectrometry (MS) proteomic analysis. The extracts were enriched for cellular signaling proteins using a mix of three different immobilized kinase inhibitors (Purvalanol B, Bisindolylmaleimide X, and (R)-3-(4-((1-Phenylethyl)amino)thieno[2,3-d]pyrimidin-6-yl)benzoic acid (SB6-060-05)) on sepharose bead columns. Raw data is deposited in the PRIDE database [1], project number PXD005286. Data presented (Table 1) shows changes relative to untreated control for each biological replicate for the three cell lines

Changes in cellular signaling proteins in extracts from A549, H460, and U2OS cells treated with cisplatin or docetaxel

Cell extracts from A549, H460, and U2OS human cancer cell lines treated with cisplatin and docetaxel were analyzed by mass spectrometry (MS) proteomic analysis. The extracts were enriched for cellular signaling proteins using a mix of three different immobilized kinase inhibitors (Purvalanol B, Bisindolylmaleimide X, and (R)-3-(4-((1-Phenylethyl)amino)thieno[2,3-d]pyrimidin-6-yl)benzoic acid (SB6-060-05)) on sepharose bead columns. Raw data is deposited in the PRIDE database [1], project number PXD005286. Data presented (Table 1) shows changes relative to untreated control for each biological replicate for the three cell lines

Dataset for: The role of PCNA as a scaffold protein in cellular signaling is functionally conserved between yeast and humans

Proliferating cell nuclear antigen (PCNA), a member of the highly conserved DNA sliding clamp family, is an essential protein for cellular processes including DNA replication and repair. A large number of proteins from higher eukaryotes contain one of two PCNA-interacting motifs: PIP-box (PCNA interacting protein-box) and APIM (AlkB homologue 2 PCNA-interacting motif). APIM has been shown to be especially important during cellular stress. PIP-box is known to be functionally conserved in yeast, and here we show that this is also the case for APIM. Several of the 84 APIM-containing yeast proteins are associated with cellular signaling as hub-proteins, which are able to interact with a large number of other proteins. Cellular signaling is highly conserved throughout evolution, and we recently suggested a novel role for PCNA as a scaffold protein in cellular signaling in human cells. A cell-penetrating peptide containing the APIM sequence increases the sensitivity towards the chemotherapeutic agent cisplatin in both yeast and human cells, and both yeast and human cells become hypersensitive when the Hog1/p38 MAPK pathway is blocked. These results suggest that the interactions between APIM-containing signaling proteins and PCNA during the DNA damage response is evolutionary conserved between yeast and mammals, and that PCNA has a role in cellular signaling also in yeast

Anti-Cancer Potential of Homemade Fresh Garlic Extract Is Related to Increased Endoplasmic Reticulum Stress

The use of garlic and garlic-based extracts has been linked to decreased incidence of cancer in epidemiological studies. Here we examine the molecular and cellular activities of a simple homemade ethanol-based garlic extract (GE). We show that GE inhibits growth of several different cancer cells in vitro, as well as cancer growth in vivo in a syngeneic orthotopic breast cancer model. Multiple myeloma cells were found to be especially sensitive to GE. The GE was fractionated using solid-phase extractions, and we identified allicin in one GE fraction; however, growth inhibitory activities were found in several additional fractions. These activities were lost during freeze or vacuum drying, suggesting that the main anti-cancer compounds in GE are volatile. The anti-cancer activity was stable for more than six months in −20 °C. We found that GE enhanced the activities of chemotherapeutics, as well as MAPK and PI3K inhibitors. Furthermore, GE affected hundreds of proteins involved in cellular signalling, including changes in vital cell signalling cascades regulating proliferation, apoptosis, and the cellular redox balance. Our data indicate that the reduced proliferation of the cancer cells treated by GE is at least partly mediated by increased endoplasmic reticulum (ER) stress