RUNX3 has been suggested to be a tumor suppressor of gastric cancer. The gastric mucosa of the Runx3-null mouse develops hyperplasia due to enhanced proliferation and suppressed apoptosis accompanied by a decreased sensitivity to transforming growth factor beta1 (TGF-beta1). It is known that TGF-beta1 induces cell growth arrest by activating CDKN1A (p21(WAF1)(/Cip1)), which encodes a cyclin-dependent kinase inhibitor, and this signaling cascade is considered to be a tumor suppressor pathway. However, the lineage-specific transcription factor that cooperates with SMADs to induce p21 expression is not known. Here we show that RUNX3 is required for the TGF-beta-dependent induction of p21 expression in stomach epithelial cells. Overexpression of RUNX3 potentiates TGF-beta-dependent endogenous p21 induction. In cooperation with SMADs, RUNX3 synergistically activates the p21 promoter. In contrast, RUNX3-R122C, a mutation identified in a gastric cancer patient, abolished the ability to activate the p21 promoter or cooperate with SMADs. Furthermore, areas in mouse and human gastric epithelium where RUNX3 is expressed coincided with those where p21 is expressed. Our results suggest that at least part of the tumor suppressor activity of RUNX3 is associated with its ability to induce p21 expression.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1234316 | PMC |
http://dx.doi.org/10.1128/MCB.25.18.8097-8107.2005 | DOI Listing |
Fam Cancer
January 2025
Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
Multiple endocrine neoplasia type 1 (MEN1) syndrome is an autosomal dominant disorder caused by a germline pathogenic variant in the MEN1 tumor suppressor gene. Patients with MEN1 have a high risk for primary hyperparathyroidism (PHPT) with a penetrance of nearly 100%, pituitary adenomas (PitAd) in 40% of patients, and neuroendocrine neoplasms (NEN) of the pancreas (40% of patients), duodenum, lung, and thymus. Increased MEN1-related mortality is mainly related to duodenal-pancreatic and thymic NEN.
View Article and Find Full Text PDFClin Transl Oncol
January 2025
Department of General Surgery, Guangzhou Digestive Disease Center, Guangzhou First People's Hospital, Guangzhou Medical University, Guangzhou, 510013, Guangdong, China.
Introduction: The transporter associated with antigen processing (TAP) is a key component of the classical HLA I antigen presentation pathway. Our previous studies have demonstrated that the downregulation of TAP1 contributes to tumor progression and is associated with an increased presence of myeloid-derived suppressor cells (MDSCs) in the tumor microenvironment. However, it remains unclear whether the elevation of MDSCs leads to immune cell exhaustion in tumors lacking TAP1.
View Article and Find Full Text PDFNaunyn Schmiedebergs Arch Pharmacol
January 2025
Department of Biochemistry, Faculty of Pharmacy, Badr University in Cairo (BUC), Badr City, , 11829, Cairo, Egypt.
Globally, the incidence and death rates associated with cancer persist in rising, despite considerable advancements in cancer therapy. Although some malignancies are manageable by a mix of chemotherapy, surgery, radiation, and targeted therapy, most malignant tumors either exhibit poor responsiveness to early identification or endure post-treatment survival. The prognosis for prostate cancer (PCa) is unfavorable since it is a perilous and lethal malignancy.
View Article and Find Full Text PDFMethods Cell Biol
January 2025
Translational Radiobiology, Department of Radiation Oncology, Uniklinikum Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, Erlangen, Germany; Comprehensive Cancer Center Erlangen-EMN, Erlangen, Germany; FAU Profile Center Immunomedicine (FAU I-MED), Friedrich-Alexander-Universität (FAU) Erlangen-Nürnberg, Schlossplatz 1, Erlangen, Germany.
Myeloid-derived suppressor cells (MDSCs) ameliorate inflammation by inhibiting T cell responses. In pathological conditions, such as autoimmunity, chronic infections or cancer they accumulate in the periphery. In cancer, MDSCs can also be part of the tumor microenvironment and are associated with a worse prognosis and limited response to immunotherapy.
View Article and Find Full Text PDFBiochem Pharmacol
January 2025
Department of Pharmacology, Faculty of Medicine, School of Health Sciences, University of Ioannina, 45110 Ioannina, Greece; Institute of Biosciences, University Research Center Ioannina, University of Ioannina, Ioannina, Greece. Electronic address:
PTEN, a tumor suppressor phosphatase, regulates cellular functions by antagonizing the growth promoting PI3K/Akt/mTOR pathway through the dephosphorylation of the second messenger PIP. Many preclinical cellular and animal studies have used PTEN inhibitors to highlight specific disease contexts where acute activation of PI3K/Akt/mTOR pathway might offer therapeutic advantages. In the present study we have re-evaluated first-generation PTEN inhibitors, including established bisperoxo-vanadium complexes (bpVs).
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!