Mutant p53s (mutp53) increase cancer invasiveness by upregulating Rab-coupling protein (RCP) and diacylglycerol kinase-α (DGKα)-dependent endosomal recycling. Here we report that mutp53-expressing tumour cells produce exosomes that mediate intercellular transfer of mutp53's invasive/migratory gain-of-function by increasing RCP-dependent integrin recycling in other tumour cells. This process depends on mutp53's ability to control production of the sialomucin, podocalyxin, and activity of the Rab3 ...[more]
Project description:Transcriptional profiling of H1299 non-small cell lung carcinoma cells transfected with either wt p53 or mut(175) p53 driven by the 5xHRE promoter (5 repeats of hypoxia-inducible factor response elements) and treated for 16 h with normoxia (21% O2) or hypoxia(<0.1% O2). 5xHRE promoter ensures that p53 expression is induced in hypoxic conditions only. Goal was to determine the transcriptional response of p53 in hypoxia and the 175 p53 mutant was used as a control as it is DNA-binding defective and transcription-incompetent mutant. Four-condition experiment: wt p53-transfected H1299 cells treated with normoxia, mut p53-transfected H1299 cells treated with normoxia, wt p53-transfected H1299 cells treated with hypoxia, mut p53-transfected H1299 cells treated with hypoxia. Biological replicates: 1 normoxic sample with wt p53, 1 normoxic sample with mut p53, 3 hypoxic samples with wt p53, 3 hypoxic samples with mut p53.
Project description:This experiment aimed to determine the genes that were upregulated when mutant p53 (R273H) was expressed. We used H1299 lung cancer cells that are endogenously p53-null and overexpressed the p53 mutant.
Project description:To evaluate the effect on lincRNA expression by p53 family members, we overexpressed p53 family members in H1299 cells and evaluated the lincRNA expression by microarray analysis. lincRNA expression was measured in H1299 cells infected with adenovirus expressing LacZ, p53, p63a, p63g, p73a and p73b.
Project description:To evaluate the effect on gene expression by p53 family members and AKR1B10, we overexpressed p53 family members in H1299 cells or knocked down AKR1B10 in HCT116 cells and evaluated the gene expression by microarray analysis. Gene expression was measured in H1299 cells infected with adenovirus expressing p53, p63g and p73b, and in HCT116 cells transfected with siRNAs targeting AKR1B10 and then treated with adriamycin.
Project description:H1299 cells were overexpressed miR-138 or silenced AGO2. The expression of 92 genes associated with p53 using the “Human p53 Signaling Pathway PCR Array” qPCR gene expression profiling. H1299 cells were transfected with NC mimics, AGO2 siRNA or miR-138 for 48h. Equal amount total RNA from each group was pooled prior to gene expression analysis.
Project description:This experiment was performed to determine which gene promoters mutant p53 binds and transcriptionally regulates in order to understand how mutant p53 accomplishes its gain of function phenotype.
Project description:RNA-sequencing was performed to determine the differences between cells that contain mutant p53 and a transactivation deficient mutant of p53 to determine why the TAD mutant cells don't form tumors.
Project description:Overexpression of mutant p53 is a common theme in tumors, suggesting a selective pressure for p53 mutation in cancer development and progression. To determine how mutant p53 expression may lead to survival advantage in human cancer cells, we generated stable cell lines expressing p53 mutants p53-R175H, -R273H, and -D281G by use of p53-null human H1299 (lung carcinoma) cells. Compared to vector-transfected cells, H1299 cells expressing mutant p53 showed a survival advantage when treated with etoposide, a common chemotherapeutic agent; however, cells expressing the transactivation-deficient triple mutant p53-D281G (L22Q/W23S) had significantly lower resistance to etoposide. Gene expression profiling of cells expressing transcriptionally active mutant p53 proteins revealed the striking pattern that all three p53 mutants induced expression of approximately 100 genes involved in cell growth, survival, and adhesion. The gene NF-kappaB2 is a prominent member of this group, whose overexpression in H1299 cells also leads to chemoresistance. Treatment of H1299 cells expressing p53-R175H with small interfering RNA specific for NF-kappaB2 made these cells more sensitive to etoposide. We have also observed activation of the NF-kappaB2 pathway in mutant p53-expressing cells. Thus, one possible pathway through which mutants of p53 may induce loss of drug sensitivity is via the NF-kappaB2 pathway.
Project description:In the present study, we used a high-throughput small RNA deep sequencing followed by a systematic computational analysis to identify genome wide mutant p53R273H regulated miRNAs in both DNA damage dependent and independent context. Several miRNA-mRNA regulatory networks have been predicted that might contribute to mutant p53 GOF properties. Differentially regulated miRNA signature profile has been validated in the lung cancer patients harboring wildtype and mutant p53. We identified specific miRNA signatures for lymph node metastasis associated with p53 mutation in lung adenocarcinoma and also predicted the possible contribution of two mutant p53 regulated miRNAs in EMT process. Furthermore, this study identified a hitherto unknown miRNA in human which might act as one of the crucial downstream targets of GOF mutant p53 to confer oncogenic properties. Determination of mutant p53R273H regulated microRNAs H1299 cells.