TRAIL mediated signaling in pancreatic cancer.

Research over the years has progressively shown substantial broadening of the tumor necrosis factor alpha- related apoptosis-inducing ligand (TRAIL)-mediated signaling landscape. Increasingly it is being realized that pancreatic cancer is a multifaceted and genomically complex disease. Suppression of tumor suppressors, overexpression of oncogenes, epigenetic silencing, and loss of apoptosis are some of the extensively studied underlying mechanisms. Rapidly accumulating in vitro and in vivo evidence has started to shed light on the resistance mechanisms in pancreatic cancer cells. More interestingly a recent research has opened new horizons of miRNA regulation by DR5 in pancreatic cancer cells. It has been shown that DR5 interacts with the core microprocessor components Drosha and DGCR8, thus impairing processing of primary let-7. Xenografting DR5 silenced pancreatic cancer cells in SCID-mice indicated that there was notable suppression of tumor growth. There is a paradigm shift in our current understanding of TRAIL mediated signaling in pancreatic cancer cells that is now adding new layers of concepts into the existing scientific evidence. In this review we have attempted to provide an overview of recent advances in TRAIL mediated signaling in pancreatic cancer as evidenced byfindings of in vitro and in vivo analyses. Furthermore, we discuss nanotechnological advances with emphasis on PEG-TRAIL and four-arm PEG cross-linked hyaluronic acid (HA) hydrogels to improve availability of TRAIL at target sites.

Genetic mapping of an autosomal recessive postaxial polydactyly type A to chromosome 13q13.3-q21.2 and screening of the candidate genes.

Postaxial Polydactyly (PAP) is characterized by fifth digit duplication in hands and/or feet. Two types of PAP including PAP-A, representing the development of well-formed extra digit, and PAP-B, representing the presence of rudimentary fifth digit, have been described. Both isolated and syndromic forms of PAP have been reported. Isolated forms of PAP usually segregate as an autosomal dominant trait and to date four loci have been identified. In the present study, we have described mapping of the first locus of autosomal recessive PAP type A on chromosome 13q13.3-13q21.2 in a consanguineous Pakistani family. Using polymorphic microsatellite markers, the disease locus was mapped to a 17.87-cM (21.13 Mb) region flanked by markers D13S1288 and D13S632, on chromosome 13q13.3-13q21.2. A maximum multipoint LOD score of 3.84 was obtained with several markers along the disease interval. DNA sequence analysis of exons and splice-junction sites of ten candidate genes (CHM-I, TSC22D1, FOXO1, DIAPH3, CCDC122, CKAP2, SUGT1, RANKL, LPAR6, C13ORF31) did not reveal potentially causal variants.

Congenital atrichia with papular lesions resulting from novel mutations in human hairless gene in four consanguineous families.

Congenital atrichia with papular lesions (APL; Mendelian Inheritance in Man no. 209500) is a rare form of irreversible alopecia that follows an autosomal recessive mode of inheritance. Patients with this form of alopecia show hair loss soon after birth with the development of papular lesions of keratin-filled cysts over the body. Several studies have reported sequence variants in the human hairless (HR) gene as the underlying cause of this disorder. In the present study, we have reported four consanguineous families showing features of APL. Genotyping using microsatellite markers showed mapping of all four families to the hairless (HR) gene on chromosome 8p21.1. Further, DNA sequence analysis of the HR gene revealed three novel mutations including two nonsense (p.Cys690X, p.Arg819X) and a missense (p.Pro1157Arg) in the four families.

A novel deletion mutation in proteoglycan-4 underlies camptodactyly-arthropathy-coxa-vara-pericarditis syndrome in a consanguineous pakistani family.

BACKGROUND AND AIMS: Camptodactyly-arthropathy-coxa-vara-pericarditis (CACP) syndrome is an autosomal recessive condition that mostly affects joints and tendons but can also affect the pericardium, which is a surface surrounding the heart. CACP syndrome is caused by mutations in a secreted proteoglycan 4 (PRG4) gene, which expresses in skeletal as well as nonskeletal tissues. We undertook this study to genetically screen a large consanguineous Pakistani family segregating CACP in an autosomal recessive manner. METHODS: Genome-wide homozygosity mapping of 10 members of a Pakistani family including six affected and four normal individuals was carried out using 250K SNP genotyping array. To screen for mutation in PRG4 gene, all coding exons and exon-intron junctions were sequenced using ABI prism 3730 automated DNA sequencer. RESULTS: Genome-wide homozygosity mapping revealed a large homozygous region on chromosome 1 carried by all the affected individuals. This region contains the previously described PRG4 gene involved in CACP syndrome. Sequence analysis of PRG4 gene in affected individuals of the family presented here revealed a 2 base-pair (bp) deletion (c.2816_2817delAA) predicting a frame shift mutation (p.Lys939fsX38). To our knowledge, this is probably the first mutation identified in PRG4 gene in a Pakistani family. CONCLUSIONS: We described a 2-bp novel deletion mutation in PRG4 gene in a Pakistani family with CACP. Our findings extend the body of evidence that only nonsense mutation in PRG4 gene triggers the phenotype.

A novel splice-acceptor site mutation in CDH3 gene in a consanguineous family exhibiting hypotrichosis with juvenile macular dystrophy.

Mutations in CDH3 gene, encoding P-cadherin, are responsible for hypotrichosis with juvenile macular dystrophy (HJMD), which is a rare autosomal recessive disorder. The HJMD is characterized by congenital sparse hair on scalp and progressive severe degenerative changes of the retinal macula which leads to variable degrees of blindness. The present study reports a large consanguineous Pakistani family with six individuals affected with HJMD. Genotyping using polymorphic microsatellite markers showed linkage of the family to CDH3 gene on chromosome 16q22.1. Sequence analysis of the CDH3 gene revealed a novel splice site mutation (c.IVS10-1 G â†’ A) in intron 10, which leads to skipping of exon 11 and probably synthesizing a non-functional premature truncated protein.

Novel mutations in G protein-coupled receptor gene (P2RY5) in families with autosomal recessive hypotrichosis (LAH3).

Autosomal recessive hypotrichosis (LAH3) is a rare hair disorder characterized by sparse hair on scalp and the rest of the body of affected individuals. Recently mutations in a G protein-coupled receptor gene, P2RY5, located at LAH3 locus, have been reported in several families with autosomal recessive hypotrichosis simplex and woolly hair. For the present study, 22 Pakistani families with autosomal recessive hypotrichosis were enrolled. Genotyping using microsatellite markers linked to three autosomal recessive forms of hypotrichosis (LAH1, LAH2, LAH3) showed the linkage of 2 families to the LAH2 locus and 14 to the LAH3 locus. The remaining 6 families were not linked to any of the three loci. Families linked to LAH3 locus were further subjected to screening of the P2RY5 gene with direct DNA sequencing. Three previously reported variants, c.69insCATG (p.24insHfs52), c.188A > T (p.D63V) and c.565G > A (p.E189K) were observed in eight families. Four novel nonsynonymous sequence variants, c.8G > C (p.S3T), c.36insA (p.D13RfsX16), c.160insA (p.N54TfsX58) and c.436G > A (p.G146R) were found to segregate within six families.