Browse
Submit Data
Databases
API
Help

Dataset Information

23 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Functional cooperation between ASK1 and p21^Waf1/Cip1 in the balance of cell-cycle arrest, cell death and tumorigenesis of stressed keratinocytes.

ABSTRACT: Both CDKN1A (p21 ^Waf1/Cip1) and Apoptosis signal-regulating kinase 1 (ASK1) play important roles in tumorigenesis. The role of p21 ^Waf1/Cip1 in attenuating ASK1-induced apoptosis by various stress conditions is well established. However, how ASK1 and p21 ^Waf1/Cip1 functionally interact during tumorigenesis is still unclear. To address this aspect, we crossed ASK1 knockout (ASK1KO) mice with p21 ^Waf1/Cip1 knockout (p21KO) mice to compare single and double-mutant mice. We observed that deletion of p21 ^Waf1/Cip1 leads to increased keratinocyte proliferation but also increased cell death. This is mechanistically linked to the ASK1 axis-induced apoptosis, including p38 and PARP. Indeed, deletion of ASK1 does not alter the proliferation but decreases the apoptosis of p21KO keratinocytes. To analyze as this interaction might affect skin carcinogenesis, we investigated the response of ASK1KO and p21KO mice to DMBA/TPA-induced tumorigenesis. Here we show that while endogenous ASK1 is dispensable for skin homeostasis, ASK1KO mice are resistant to DMBA/TPA-induced tumorigenesis. However, we found that epidermis lacking both p21 and ASK1 reacquires increased sensitivity to DMBA/TPA-induced tumorigenesis. We demonstrate that apoptosis and cell-cycle progression in p21KO keratinocytes are uncoupled in the absence of ASK1. These data support the model that a critical event ensuring the balance between cell death, cell-cycle arrest, and successful divisions in keratinocytes during stress conditions is the p21-dependent ASK1 inactivation.

SUBMITTER: De Blasio C

PROVIDER: S-EPMC8042117 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Lycorine hydrochloride inhibits melanoma cell proliferation, migration and invasion via down-regulating p21Cip1/WAF1.

Project description:Lycorine hydrochloride (LH) is an active ingredient sourced from the medicinal herb Lycoris radiata. Previous studies have suggested that LH exerts tumor suppression activity in several human cancers. However, the anti-cancer effect of LH in melanoma and the potential molecular mechanisms still need to be further studied. p21Cip1/WAF1, unlike its traditional cyclin-dependent kinase (CDK) inhibitor role, is believed to act as an oncogene under certain cellular conditions. In this research, an increased expression of p21Cip1/WAF1 was found in human melanoma tissues and positively related to the tumor invasion depth. High level of p21Cip1/WAF1 was found to correlate with bad outcomes of melanoma patients by Kaplan-Meier survival analysis. Functional experiments demonstrated that the proliferation, migration and invasion ability of A375 and MV3 melanoma cells was powerfully inhibited by LH through inducing S phase cell cycle arrest and regulating epithelial-mesenchymal transition (EMT). In NOD/SCID mice model, LH effectively inhibited the xenograft tumor growth and lung metastasis of A375 cells. Further research revealed that LH reduced p21Cip1/WAF1 protein by accelerating its ubiquitination. Importantly, the LH-induced suppression of cell proliferation and metastasis was rescued by p21Cip1/WAF1 overexpression, both in vitro an in vivo. Taken together, LH, which suppresses the proliferation and metastasis of melanoma cells via down-regulating p21Cip1/WAF1, is expected to be developed as an effective medicine for melanoma therapy.

| S-EPMC8085853 | biostudies-literature

Mist1 regulates pancreatic acinar cell proliferation through p21 CIP1/WAF1.

Project description:Background & aimsMist1 is a basic helix-loop-helix (bHLH) transcription factor that is important to the proper development of the exocrine pancreas. The aim of this study was to investigate the role of Mist1 in modulating acinar cell proliferation.MethodsDuctal and acinar pancreatic cell lines were engineered to express an inducible Mist1 complementary DNA or to express a short hairpin RNA that targeted endogenous Mist1. Alterations in RNA and protein levels were detected by real-time reverse-transcription polymerase chain reaction and immunoblots. Chromatin immunoprecipitation and reporter gene assays were performed to map Mist1-responsive elements on target genes; the overall proliferation index of acinar cells from Mist1 null pancreata was evaluated by immunohistochemistry.ResultsExpression of Mist1 resulted in a significant decrease in the proliferative potential of cells that was associated with induced expression of p21(CIP1/WAF1). Short hairpin RNA-directed knockdown of p21(CIP1/WAF1) generated cells that were refractory to Mist1 expression, whereas knockdown of Mist1 transcripts or deletion of Mist1 from the mouse genome led to increased cell proliferation and a concomitant decrease in p21(CIP1/WAF1) protein levels. Surprisingly, Mist1-dependent activation of the p21(CIP1/WAF1) promoter was independent of classic basic helix-loop-helix protein binding sites. Instead, Sp1 binding sites were essential for Mist1-dependent transcription, suggesting that Mist1 activates p21(CIP1/WAF1) expression through a unique Sp1 pathway. Indeed, coimmunoprecipitation studies demonstrated that Mist1 and Sp1 were found within the same transcription complex.ConclusionsOur results show that Mist1 has a dual role in the development of the exocrine pancreas: controlling cell proliferation and promoting terminal differentiation.

| S-EPMC2853247 | biostudies-literature

Loss of Notch1-dependent p21(Waf1/Cip1) expression influences the Notch1 outcome in tumorigenesis.

Project description:Notch signaling plays a complex role in carcinogenesis, and its signaling pathway has both tumor-suppressor and oncogenic components. In this study we investigated the effects of reactive oxygen species (ROS) on Notch1 signaling outcome in keratinocyte biology. We demonstrate that Notch1 function contributes to the arsenic-induced keratinocyte transformation. We found that acute exposure to arsenite increases oxidative stress and inhibits proliferation of keratinocyte cells by upregulation of p21(waf1/Cip1). The necessity of p21(waf1/Cip1) for arsenite-induced cell death was demonstrated by targeted downregulation of p21(waf1/Cip1) by using RNA interference. We further demonstrated that on acute exposure to arsenite, p21(waf1/Cip1) is upregulated and Notch1 downmodulated, whereas on chronic exposure to arsenite, malignant progression of arsenite-treated keratinocytes cells was accompanied by regained expression and activity of Notch1. Notch1 activity in arsenite-transformed keratinocytes inhibits arsenite-induced upregulation of p21(waf1/Cip1) by sustaining c-myc expression. We further demonstrated that c-myc collaborates with Nrf2, a key regulator for the maintenance of redox homeostasis, to promote metabolic activities that support cell proliferation and cytoprotection. Therefore, Notch1-mediated repression of p21(waf1/Cip1) expression results in the inhibition of cell death and keratinocytes transformation. Our results not only demonstrate that sustained Notch1 expression is at least one key event implicated in the arsenite human skin carcinogenic effect, but also may provide mechanistic insights into the molecular aspects that determine whether Notch signaling will be either oncogenic or tumor suppressive.

| S-EPMC4111696 | biostudies-literature

The p21(WAF1/CIP1) promoter is methylated in Rat-1 cells: stable restoration of p53-dependent p21(WAF1/CIP1) expression after transfection of a genomic clone containing the p21(WAF1/CIP1) gene.

Project description:Rat-1 cells are used in many studies on transformation, cell cycle, and apoptosis. Whereas UV treatment of Rat-1 cells results in apoptosis, X-ray treatment does not induce either apoptosis or a cell cycle block. X-ray treatment of Rat-1 cells results in both an increase of p53 protein and expression of the p53-inducible gene MDM2 but not the protein or mRNA of the p53-inducible p21(WAF1/CIP1) gene, which in other cells plays an important role in p53-mediated cell cycle block. The lack of p21(WAF1/CIP1) expression appears to be the result of hypermethylation of the p21(WAF1/CIP1) promoter region, as p21(WAF1/CIP1) protein expression could be induced by growth of Rat-1 cells in the presence of 5-aza-2-deoxycytidine. Furthermore, sequence analysis of bisulfite-treated DNA demonstrated extensive methylation of cytosine residues in CpG dinucleotides in a CpG-rich island in the promoter region of the p21(WAF1/CIP1) gene. Stable X-ray-induced p53-dependent p21(WAF1/CIP1) expression and cell cycle block were restored to a Rat-1 clone after transfection with a P1 artificial chromosome (PAC) DNA clone containing a rat genomic copy of the p21(WAF1/CIP1) gene. The absence of expression of the p21(WAF1/CIP1) gene may contribute to the suitability of Rat-1 cells for transformation, cell cycle, and apoptosis studies.

| S-EPMC85267 | biostudies-literature

RUNX3 suppresses gastric epithelial cell growth by inducing p21(WAF1/Cip1) expression in cooperation with transforming growth factor {beta}-activated SMAD.

Project description: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.

| S-EPMC1234316 | biostudies-literature

Chloroquine reverses chemoresistance via upregulation of p21WAF1/CIP1 and autophagy inhibition in ovarian cancer.

Project description:Overcoming drug-resistance is a big challenge to improve the survival of patients with epithelial ovarian cancer (EOC). In this study, we investigated the effect of chloroquine (CQ) and its combination with cisplatin (CDDP) in drug-resistant EOC cells. We used the three EOC cell lines CDDP-resistant A2780-CP20, RMG-1 cells, and CDDP-sensitive A2780 cells. The CQ-CDDP combination significantly decreased cell proliferation and increased apoptosis in all cell lines. The combination induced expression of γH2AX, a DNA damage marker protein, and induced G2/M cell cycle arrest. Although the CQ-CDDP combination decreased protein expression of ATM and ATR, phosphorylation of ATM was increased and expression of p21WAF1/CIP1 was also increased in CQ-CDDP-treated cells. Knockdown of p21WAF1/CIP1 by shRNA reduced the expression of γH2AX and phosphorylated ATM and inhibited caspase-3 activity but induced ATM protein expression. Knockdown of p21WAF1/CIP1 partly inhibited CQ-CDDP-induced G2/M arrest, demonstrating that knockdown of p21WAF1/CIP1 overcame the cytotoxic effect of the CQ-CDDP combination. Ectopic expression of p21WAF1/CIP1 in CDDP-treated ATG5-shRNA/A2780-CP20 cells increased expression of γH2AX and caspase-3 activity, demonstrating increased DNA damage and cell death. The inhibition of autophagy by ATG5-shRNA demonstrated similar results upon CDDP treatment, except p21WAF1/CIP1 expression. In an in vivo efficacy study, the CQ-CDDP combination significantly decreased tumor weight and increased expression of γH2AX and p21WAF1/CIP1 in A2780-CP20 orthotopic xenografts and a drug-resistant patient-derived xenograft model of EOC compared with controls. These results demonstrated that CQ increases cytotoxicity in combination with CDDP by inducing lethal DNA damage by induction of p21WAF1/CIP1 expression and autophagy inhibition in CDDP-resistant EOC.

| S-EPMC7718923 | biostudies-literature

The Multifaceted p21 (Cip1/Waf1/CDKN1A) in Cell Differentiation, Migration and Cancer Therapy.

Project description:Loss of cell cycle control is characteristic of tumorigenesis. The protein p21 is the founding member of cyclin-dependent kinase inhibitors and an important versatile cell cycle protein. p21 is transcriptionally controlled by p53 and p53-independent pathways. Its expression is increased in response to various intra- and extracellular stimuli to arrest the cell cycle ensuring genomic stability. Apart from its roles in cell cycle regulation including mitosis, p21 is involved in differentiation, cell migration, cytoskeletal dynamics, apoptosis, transcription, DNA repair, reprogramming of induced pluripotent stem cells, autophagy and the onset of senescence. p21 acts either as a tumor suppressor or as an oncogene depending largely on the cellular context, its subcellular localization and posttranslational modifications. In the present review, we briefly mention the general functions of p21 and summarize its roles in differentiation, migration and invasion in detail. Finally, regarding its dual role as tumor suppressor and oncogene, we highlight the potential, difficulties and risks of using p21 as a biomarker as well as a therapeutic target.

| S-EPMC6770903 | biostudies-literature

p300 alters keratinocyte cell growth and differentiation through regulation of p21(Waf1/CIP1).

Project description:Backgroundp300 functions as a transcriptional co-activator to regulate many cellular responses such as cell growth, transformation, development and differentiation. It has been shown to affect the transcriptional activity of p53 which regulates p21(Waf1/CIP1) expression, however, the role of p300 in differentiation remains unclear.Methodology and principal findingsKnockdown of p300 protein with short hairpin RNA (shRNA) molecules delays human neonatal foreskin keratinocyte (HFKs) differentiation. Moreover, depletion of p300 increases the proliferative capacity of HFKs, extends the life span of cells and allows differentiated HFKs to re-enter the cell cycle. Studies indicate that depletion of p300 down-regulates the acetylation and expression of p53, and chromatin immunoprecipitation (ChIP) analysis shows that induction of p21(Waf1/CIP1) in early differentiation is a result of p300 dependent activation of p53 and that depletion of p21(Waf1/CIP1) results in the delay of differentiation and a phenotype similar to p300 depletion.Conclusionsp300 has a direct role in the control of cell growth and differentiation in primary epithelial cells, and p21(Waf1/CIP1) is an important mediator of these p300 functions.

| S-EPMC2805707 | biostudies-literature

TFEB Modulates p21/WAF1/CIP1 during the DNA Damage Response.

Project description:The MiT/TFE family of transcription factors (MITF, TFE3, and TFEB), which control transcriptional programs for autophagy and lysosome biogenesis have emerged as regulators of energy metabolism in cancer. Thus, their activation increases lysosomal catabolic function to sustain cancer cell growth and survival in stress conditions. Here, we found that TFEB depletion dramatically reduces basal expression levels of the cyclin-dependent kinase (CDK) inhibitor p21/WAF1 in various cell types. Conversely, TFEB overexpression increases p21 in a p53-dependent manner. Furthermore, induction of DNA damage using doxorubicin induces TFEB-mediated activation of p21, delays G2/M phase arrest, and promotes cell survival. Pharmacological inhibition of p21, instead, abrogates TFEB-mediated protection during the DNA damage response. Together, our findings uncover a novel and direct role of TFEB in the regulation of p21 expression in both steady-state conditions and during the induction of DNA-damage response (DDR). Our observations might open novel therapeutic strategies to promote cancer cell death by targeting the TFEB-p21 pathway in the presence of genotoxic agents.

| S-EPMC7290768 | biostudies-literature

The DEAD-box RNA helicase DDX41 is a novel repressor of p21WAF1/CIP1 mRNA translation.

Project description:The cyclin-dependent kinase inhibitor p21 is an important player in stress pathways exhibiting both tumor-suppressive and oncogenic functions. Thus, expression of p21 has to be tightly controlled, which is achieved by numerous mechanisms at the transcriptional, translational, and posttranslational level. Performing immunoprecipitation of bromouridine-labeled p21 mRNAs that had been incubated before with cytoplasmic extracts of untreated HCT116 colon carcinoma cells, we identified the DEAD-box RNA helicase DDX41 as a novel regulator of p21 expression. DDX41 specifically precipitates with the 3'UTR, but not with the 5'UTR, of p21 mRNA. Knockdown of DDX41 increases basal and γ irradiation-induced p21 protein levels without affecting p21 mRNA expression. Conversely, overexpression of DDX41 strongly inhibits expression of a FLAG-p21 and a luciferase construct, but only in the presence of the p21 3'UTR. Together, these data suggest that this helicase regulates p21 expression at the translational level independent of the transcriptional activity of p53. However, knockdown of DDX41 completely fails to increase p21 protein levels in p53-deficient HCT116 cells. Moreover, posttranslational up-regulation of p21 achieved in both p53+/+ and p53-/- HCT116 cells in response to pharmaceutical inhibition of the proteasome (by MG-132) or p90 ribosomal S6 kinases (by BI-D1870) is further increased by knockdown of DDX41 only in p53-proficient but not in p53-deficient cells. Although our data demonstrate that DDX41 suppresses p21 translation without disturbing the function of p53 to directly induce p21 mRNA expression, this process indirectly requires p53, perhaps in the form of another p53 target gene or as a still undefined posttranscriptional function of p53.

| S-EPMC5437239 | biostudies-literature