ABSTRACT
The Ewing's sarcoma family can present diagnostic difficulties. In the past the basis of diagnosis has been a exclusion. Identification of a specific translocation especially t(11;22) (EWS-FLI 1 fusion gene), which is seen in nearly 85 percent of Ewing's sarcoma cases can help in precise diagnosis. We have carried out a study on twenty patient samples diagnosed to have Ewing's sarcoma/peripheral neuroectodermal tumour (PNET)/small round cell malignant tumour. The study involved RT-PCR analysis for the fusion transcript, followed by sequencing to identify the specific type of fusion. Ninety percent (18/20) of the samples tested were found to be t(11;22) translocations involving EWS-FLI 1 genes. Sixty-one percent (11/18) were found to be type 1 fusion and seven were type 2 (39 percentage). This is the first study in India with quantitative information about the types of EWS-FLI 1 translocations present in Ewing's family of tumours in south Indian patients.
Subject(s)
Chromosomes, Human, Pair 11 , Chromosomes, Human, Pair 22 , Neuroectodermal Tumors, Primitive, Peripheral/classification , Neuroectodermal Tumors, Primitive, Peripheral/genetics , Sarcoma, Ewing/classification , Sarcoma, Ewing/genetics , Translocation, Genetic , Adolescent , Adult , Child , Female , Humans , India , Male , Middle Aged , Neuroectodermal Tumors, Primitive, Peripheral/diagnosis , Oncogene Proteins, Fusion/genetics , Proto-Oncogene Protein c-fli-1 , RNA-Binding Protein EWS , Sarcoma, Ewing/diagnosis , Transcription Factors/geneticsABSTRACT
We have studied the chemopreventive effect of d-limonene, a monoterpene monocyclic compound, against N-nitrosodiethylamine (NDEA) alone and along with phenobarbital (PB) induced hepatocarcinogenesis in AKR mice. Histopathological analysis clearly indicates the maintenance of normal features when the mice were given limonene 15 days prior to carcinogen treatment. The immunohistochemical analysis of c-jun and c-myc oncoprotein shows an increased protein expression (2-3 fold) in NDEA and NDEA-PB mediated hepatocarcinogenesis after 60 days of NDEA treatment. Our earlier work by northern blot analysis has already indicated an increased transcription of c-jun and c-myc in NDEA mediated hepatocarcinogenesis. However, such overexpression of c-myc and c-jun both at mRNA and oncoprotein levels has been completely inhibited when d-limonene was used along with NDEA or NDEA-PB. Thus, the present investigation explains the anti-tumour effect of d-limonene for the first time on the level of oncogene expression in NDEA and NDEA-PB mediated hepatocarcinogenesis.
