mRNA differential display of gene expression in colonic carcinoma

Abstract

We analyzed changes in gene expression in human colonic carcinoma by fluorescent mRNA differential display. RNA isolated from two samples of normal colon and four cases of colonic adenocarcinoma were amplified with a 15 x 32 set of primers resulting in 2880 cDNAs analyzed with an automated sequencer. Electrophoretic patterns implying constitutive gene expression as well as upregulated and downregulated expression in carcinomas were identified. Forty such cDNA fragments were purified by a novel fluorescent polyacrylamide gel electrophoresis (PAGE)-based method and identified by cyclic sequencing. Most genes showing differential expression were upregulated in colonic carcinoma. Upregulated genes included those for various ribosomal and mitochondrial proteins, heat shock proteins, nucleolar RNA-helicase and phosphoserine aminotransferase. Downregulated genes included histone H3.3. In conclusion, genes associated with vital cellular functions such as transcription, protein synthesis and mitochondrial metabolism were upregulated in colonic carcinoma. Fluorescent mRNA differential display can be applied to the identification of novel cancer-related genes for diagnostic, prognostic and therapeutic purposes.

Putative DEAD and DExH-box RNA helicases families in Entamoeba histolytica

“…The URH49 helicase mRNA level decreases three to six-fold when HeLa cells enter quiescence (Pryor et al, 2004). A nucleolar RNA helicase has been identified as an upregulated gene in human colonic carcinoma by fluorescent mRNA differential display (Ojala et al, 2002). Similarly, the DDX39 DEAD-box RNA helicase is overtranscribed in human lung squamous cell carcinoma and promotes colony formation of HeLa cells (Sugiura et al, 2007).…”

A large-scale screening of the normalized mammalian mitochondrial gene expression profiles

“…There are indications that other important physiological and pathological processes, such as cell differentiation (Angenieux et al, 2001), immortalization (Kim et al, 2001) or tumorigenesis (Ojala et al, 2002;Haugen et al, 2003;Baris et al, 2004), are also associated with alterations in total mitochondrial gene expression. However, the applied algorithm failed to associate these processes with characteristic alterations in expression of mitochondrial transcripts.…”

Pyruvate kinase M2 promotes de novo serine synthesis to sustain mTORC1 activity and cell proliferation

“…There are three enzymes, 3-phospho-glycerate dehydrogenase (PHGDH), phosphoserine aminotransferase 1 (PSAT1), and phosphoserine phosphatase (PSPH), which are required for the three-step conversion of the glycolytic intermediate 3-PG to serine. All three enzymes have previously been found to be overexpressed or demonstrate increased activity in tumor tissue (29)(30)(31)(32)(33)(34), suggesting this serine synthetic pathway may play an important role in tumorigenesis. To test this idea, we blocked this pathway by suppressing PSAT1 with RNAi.…”