Chronic myelogenous leukemia evolves in two clinically distinct stages: a chronic and a blast crisis phase. The molecular changes associated with chronic phase to blast crisis transition are largely unknown. We have identified a cDNA clone, DR-nm23, differentially expressed in a blast-crisis cDNA library, which has '70% sequence similarity to the putative metastatic suppressor genes, nm23-H1 and nm23-H2. The deduced amino acid sequence similarity to the proteins encoded by these two latter genes is -65% and includes domains and amino acid residues (the leucine zipperlike and the RGD domain, a serine and a histidine residue in the NH2-and in the COOH-terminal portion of the protein, respectively) postulated to be important for nm23 function.DR-nm23 mRNA is preferentially expressed at early stages of myeloid differentiation of highly purified CD34+ cells. Its constitutive expression in the myeloid precursor 32Dc13 cell line, which is growth-factor dependent for both proliferation and differentiation, results in inhibition of granulocytic differentiation induced by granulocyte colony-stimulating factor and causes apoptotic cell death. These results are consistent with a role forDR-nm23 in normal hematopoiesis and raise the possibility that its overexpression contributes to differentiation arrest, a feature of blastic transformation in chronic myelogenous leukemia.

Copper homeostasis and distribution is strictly regulated by a network of transporters and intracellular chaperones encoded by a group of genes collectively known as copper homeostasis genes ( CHG s). In this work, analysis of The Cancer Genome Atlas database for somatic point mutations in colorectal cancer revealed that inactivating mutations are absent or extremely rare in CHG s. Using oligonucleotide microarrays, we found a strong increase in mRNA levels of the membrane copper transporter 1 protein [ CTR 1; encoded by the solute carrier family 31 member 1 gene ( SLC 31A1 gene)] in our series of colorectal carcinoma samples. CTR 1 is the main copper influx transporter and changes in its expression are able to induce modifications of cellular copper accumulation. The increased SLC 31A1 mRNA level is accompanied by a parallel increase in transcript levels for copper efflux pump ATP 7A, copper metabolism Murr1 domain containing 1 ( COMMD 1), the cytochrome C oxidase assembly factors [synthesis of cytochrome c oxidase 1 ( SCO 1) and cytochrome c oxidase copper chaperone 11 ( COX 11)], the cupric reductase six transmembrane epithelial antigen of the prostate ( STEAP 3), and the metal‐regulatory transcription factors ( MTF 1, MTF 2) and specificity protein 1 ( SP 1). The significant correlation between SLC 31A1 , SCO 1 , and COX 11 mRNA levels suggests that this transcriptional upregulation might be part of a coordinated program of gene regulation. Transcript‐level upregulation of SLC 31A1 , SCO 1 , and COX 11 was also confirmed by the analysis of different colon carcinoma cell lines (Caco‐2, HT 116, HT 29) and cancer cell lines of different tissue origin ( MCF 7, PC 3). Finally, exon‐level expression analysis of SLC 31A1 reveals differential expression of alternative transcripts in colorectal cancer and normal colonic mucosa.

We re-examined the correlation between Broad Genomic Aberrations (BGAs) and transcriptomic profiles in Colorectal Cancer (CRC). Two types of BGAs have been examined: Broad Copy-Number Abnormal regions (BCNAs), distinguished in gain- and loss-type, and Copy-Neutral Loss of Heterozygosities (CNLOHs). Transcripts are classified as “OverT” or “UnderT” if overexpressed or underexpressed comparing CRCs bearing a specific BGA to CRCs not bearing it and as “UpT” or “DownT” if upregulated or downregulated in cancer compared to normal tissue. BGA-associated effects were evaluated by changes in the “Chromosomal Distribution Index” (CDI) of different transcript classes. Data show that UpT are more sensitive than DownT to BCNA-associated gene dosage effects. “Over-UpT” genes are upregulated in cancer and further overexpressed by gene dosage, defining the so called “positive caricature transcriptomic effect”. When Over-UpT genes are ranked according to overexpression, top positions are occupied by genes implicated at the functional and therapeutic level in CRC. We show that cancer-upregulated transcripts are sensitive markers of BCNA-induced effects and suggest that analysis of positive caricature transcriptomic effects can provide clues toward the identification of BCNA-associated cancer driver genes.

Zinc is a transition metal and catalytic cofactor involved in many biological processes including proliferation, development, differentiation, and metabolism. Zinc transporters (ZnTs) play a fundamental role in cellular zinc homeostasis. ZnTs are responsible of zinc efflux and are encoded by 10 genes belonging to solute carrier family 30A (SLC30A1-10), while zinc-regulated transporter (ZRT)/iron-regulated transporter (IRT)-like protein (ZIP) transporters are responsible for the influx of zinc into the cytoplasm and are encoded by 14 genes belonging to solute carrier family 39A (SLC39A1-14). In this study, we analyzed, by transcriptome analysis, the microRNA levels of ZnT-encoding and ZIP-encoding genes in colorectal cancer (CRC) samples matched to normal colon tissues and in CRC cell lines. Results revealed an upregulation of specific ZnT and ZIP transcripts in CRC. Upregulation of SLC30A5, SLC30A6, SLC30A7 transcripts, encoding zinc efflux transporters ZnT5, ZnT6, ZnT7, localized on endoplasmic reticulum membranes, might be part of a coordinated transcriptional program associated to the increased activity of the early secretory pathway, while transcriptional upregulation of several specific ZIP transporters (SLC39A6, SLC39A7, SLC39A9, SLC39A10, and SLC39A11) could contribute in meeting the increased demand of zinc in cancer cells. Moreover, exon-level analysis of SLC30A9, a nuclear receptor coactivator involved in the transcriptional regulation of Wnt-responsive genes, revealed the differential expression of alternative transcripts in CRC and normal colonic mucosa.

The level of the mRNA for glial fibrillary acidic protein (GFAP), the major protein of the intermediate filaments of astroglial cells, and the activity of glutamine synthetase (GS), an enzyme selectively localized in astrocytes, were measured at different times after a unilateral mechanical lesion in the rat cerebral cortex. A rapid and early increase (6 hours post-lesion) in GFAP mRNA was observed; GFAP mRNA level reached a peak at 1-3 days and then decreased. Moreover, an astrocytic activation in cortical zones far from the injury site and in the contralateral hemisphere was detected. No change of GS activity was observed in the same model of brain injury, showing that this astroglial marker is not modified during the reactive gliosis obtained with this experimental model. GFAP mRNA has also been detected in the rat sciatic nerve; however, its level was not modified after nerve transection, suggesting a different regulation of GFAP expression in the peripheral nervous system.