The Clinical Utility of Determining the Allelic Background of Mutations Causing Alpha-1 Antitrypsin Deficiency: The Case with the Null Variant Q0(Mattawa)/Q0(Ourém).

Background: Alpha-1 antitrypsin deficiency (AATD) is caused by genetic variants in the gene conferring risk of developing emphysema. The clinical expression of AATD-related emphysema mostly occurs in carriers of 2 deficient alleles. By DNA sequencing of , numerous rare variants have been identified.

Dual roles for splice variants of the glucuronidation pathway as regulators of cellular metabolism.

Transcripts of the UGT1A gene, encoding half of human UDP-glucuronosyltransferase (UGT) enzymes, undergo alternative splicing, resulting in active enzymes named isoforms 1 (i1s) and novel truncated isoforms 2 (i2s). Here, we investigated the effects of depleting endogenous i2 on drug response and attempted to unveil any additional biologic role(s) for the truncated novel UGT proteins. We used an integrated systems biology approach that combines RNA interference with unbiased global genomic and proteomic screens, and used HT115 colorectal cancer cells as a model.

Overexpression of uridine diphospho glucuronosyltransferase 2B17 in high-risk chronic lymphocytic leukemia.

Uridine diphospho glucuronosyltransferase 2B17 (UGT2B17) glucuronidates androgens and xenobiotics including certain drugs. The UGT2B17 gene shows a remarkable copy number variation (CNV), which predisposes for solid tumors and influences drug response. Here, we identify a yet undescribed UGT2B17 mRNA overexpression in poor-risk chronic lymphocytic leukemia (CLL).

Protein-protein interactions between the bilirubin-conjugating UDP-glucuronosyltransferase UGT1A1 and its shorter isoform 2 regulatory partner derived from alternative splicing.

The oligomerization of UGTs [UDP (uridine diphosphate)-glucuronosyltransferases] modulates their enzyme activities. Recent findings also indicate that glucuronidation is negatively regulated by the formation of inactive oligomeric complexes between UGT1A enzymes [i1 (isoform 1)] and an enzymatically inactive alternatively spliced i2 (isoform 2). In the present paper, we assessed whether deletion of the UGT-interacting domains previously reported to be critical for enzyme function might be involved in i1-i2 interactions.

The impact of germline genetic variations in hydroxysteroid (17-beta) dehydrogenases on prostate cancer outcomes after prostatectomy.

Background: The relationship between polymorphisms in the hydroxysteroid (17-beta) dehydrogenase (HSD17B) family of genes, which are involved in steroid hormone biotransformation, and the risk of prostate cancer (PCa) progression remains unexplored.

Objective: Determine whether inherited variations in HSD17B genes are associated with PCa progression.

Design, Setting, And Participants: We studied two independent Caucasian cohorts composed of 526 men with organ-confined PCa and 213 men with advanced disease who had a median follow-up of 7.

Deletions of the androgen-metabolizing UGT2B genes have an effect on circulating steroid levels and biochemical recurrence after radical prostatectomy in localized prostate cancer.

Context: The prognostic relevance of inherited variations in hormone-related genes in the context of prostate cancer (PCa) progression has not been well studied. Of these, UDP-glucuronosyltransferase (UGT) gene products lead to inactivation of steroids.

Objective: Our objective was to determine whether polymorphisms in five UGT genes, involved in steroid metabolism, are associated with the risk of biochemical recurrence after radical prostatectomy (RP) and to examine their relationship with hormonal exposure.

SRD5A polymorphisms and biochemical failure after radical prostatectomy.

Background: The relationship between inherited germ-line variations in the 5α-reductase pathways of androgen biosynthesis and the risk of biochemical recurrence (BCR) after radical prostatectomy (RP) remains an unexplored area.

Objective: To determine the link between germ-line variations in the steroid-5α-reductase, α-polypeptide 1 (SRD5A1) and steroid-5α-reductase, α-polypeptide 2 (SRD5A2) genes and BCR.

Design, Settings, And Participants: We studied retrospectively two independent cohorts composed of 526 white (25% BCR) and 320 Asian men (36% BCR) with pathologically organ-confined prostate cancer who had a median follow-up of 88.

Immunohistochemical expression of conjugating UGT1A-derived isoforms in normal and tumoral drug-metabolizing tissues in humans.

Glucuronidation by UDP-glucuronyltransferase (UGT) enzymes is the prevailing conjugative pathway for the metabolism of both xenobiotics and endogenous compounds. Alterations in this pathway, such as those generated by common genetic polymorphisms, have been shown to significantly impact on the health of individuals, influencing cancer susceptibility, responsiveness to drugs and drug-induced toxicity. Alternative usage of terminal exons leads to UGT1A-derived splice variants, namely the classical and enzymatically active isoforms 1 (i1) and the novel enzymatically inactive isoforms 2 (i2).

Alternatively spliced products of the UGT1A gene interact with the enzymatically active proteins to inhibit glucuronosyltransferase activity in vitro.

UDP-glucuronosyltransferases (UGTs) are major mediators in conjugative metabolism. Current data suggest that UGTs, which are anchored in the endoplasmic reticulum membrane, can oligomerize with each other and/or with other metabolic enzymes, a process that may influence their enzymatic activities. We demonstrated previously that the UGT1A locus encodes previously unknown isoforms (denoted "i2"), by alternative usage of the terminal exon 5.

Extensive splicing of transcripts encoding the bile acid-conjugating enzyme UGT2B4 modulates glucuronidation.

Background And Aims: UGT2B4 is a member of the UDP-glucuronosyltransferase (UGT) superfamily, a major detoxifying system in humans. UGT2B4 is involved in bile acids metabolism and highly expressed in liver and extrahepatic tissues. The aim of this study was to uncover new molecular mechanisms underlying interindividual variability in the UGT2B4 pathway.

UGT genomic diversity: beyond gene duplication.

The human uridine diphospho (UDP)-glucuronosyltransferase (UGT) superfamily comprises enzymes responsible for a major biotransformation phase II pathway: the glucuronidation process. The UGT enzymes are located in the endoplasmic reticulum of almost all tissues, where they catalyze the inactivation of several endogenous and exogenous molecules, including bilirubin, sex steroids, numerous prescribed drugs, and environmental toxins. This metabolic pathway is particularly variable.

Genetic diversity at the UGT1 locus is amplified by a novel 3' alternative splicing mechanism leading to nine additional UGT1A proteins that act as regulators of glucuronidation activity.

Background: The gene UGT1 encodes phase II detoxification proteins involved in the elimination of small hydrophobic substances of both endogenous and exogenous origin. To date, nine functional UGT1A proteins are known to be produced from a single gene composed of alternative first exons shared with four common exons. Recently, a novel exon (referred to as exon 5b) was identified in the common shared region.

Epidermis promotes dermal fibrosis: role in the pathogenesis of hypertrophic scars.

Hypertrophic scarring is a pathological process characterized by fibroblastic hyperproliferation and by excessive deposition of extracellular matrix components. It has been hypothesized that abnormalities in epidermal-dermal crosstalk explain this pathology. To test this hypothesis, a tissue-engineered model of self-assembled reconstructed skin was used in this study to mimic interactions between dermal and epidermal cells in normal or pathological skin.