BRCA1 protein expression and its correlation with ER/PR status in sporadic and familial breast cancer in Eastern Indian patients--a hospital based study.

BRCA1 gene expression in familial breast cancer is mainly focused on mutational analysis. However in sporadic cancers BRCA1 protein expression is the main area of interest because somatic inactivation of one allele of the gene is likely to occur during the oestrogen mediated proliferation at puberty and subsequent tumourigenic events take place in the same cell. Standard immunohistochemical analysis was used to assess BRCA1 and oestrogen/progesterone receptor (ER/PR) status in familial and sporadic breast cancer patients and correlation of BRCA1 protein expression with histopathological features ER/PR status was studied in these tumours. One hundred and seventy-seven sporadic tumours (group A) and 28 familial tumours (patients with history of breast cancer in first or second degree relative ie, group B) were studied. In group A, 61 tumours had absent/reduced BRCA 1 protein expression; 30 (49%) out of these were negative for ER/PR receptors. In group B, 18 patients had absent/reduced BRCA1 protein expression, and 10 (55.6%) out of these, were ER/PR negative. Overall in 2 groups, 82 tumours were of grade 1, 61 tumours of grade 2 and 62 tumours were of grade 3 differentiation. Test of proportion showed that percentage of ER/PR negativity is significantly higher than ER/PR positivity in sporadic as well as in familial tumours with absent/ reduced BRCA 1 protein expression (p < 0.05). Sporadic tumours with deranged BRCA1 protein expression like familial tumours have more unfavourable histopathological characteristics and are likely to be of higher grade and oestrogen receptor negative

Clinical relevance of HBV DNA load in patients with chronic hepatitis B infection.

BACKGROUND: Hepatitis B virus (HBV) DNA detection and quantification are now playing an increasing role in the assessment of disease activity and response to therapy. However, viraemia levels which define various stages of HBV infection have not yet been established. AIM: To define viraemia levels which describe various stages of chronic hepatitis B virus infection. METHODS: In a retrospective study, stored sera samples of chronic hepatitis B virus (CHB) infected patients registered at AIIMS liver clinic, from January 1996 to June 2005 were subjected to competitive, quantitative PCR analysis. RESULTS: The median HBV DNA load was lowest among carriers and highest among patients with chronic hepatitis B [0 (0-8) vs. 7 (0-12) log10 copies/ml, respectively; p<0.05]. As compared to chronic hepatitis patients the DNA load was also lower among cirrhotics [7 (0-12) vs. 4.5 (0-8) log10 copies/ml, respectively; p<0.05] and hepatocellular cancer patients [ 7(0-12) vs. 0 (0-8) log10 copies/ml, respectively; p<0.05]. Patients with carriers had a DNA load which was significantly lower than e antigen negative CHB [0 (0-8) vs. 6 (0-10) log10 copies/ml; p<0.05] or e antigen positive CHB [0 (0-8) vs 8 (0-12) log10 copies/ml; p<0.05]. A threshold of 3.5 log10 copies/ml had sensitivity and specificity of 83% and 58% respectively in differentiating carriers from e antigen negative CHB. There was a strong positive correlation of HBV DNA load with inflammatory grade (R=0.334; p=0.0001), fibrosis stage (R=0.276; p=0.001) and ALT levels (R=0.378; p=0.0001). 82% (9/11) of those who lost e antigen had a decline in HBV DNA levels to <5 log10 copies/ml, whereas only 12.5% (1/8) of those who did not lose e antigen had a decline in DNA load below this level. CONCLUSIONS: HBV DNA viraemia levels correlate positively with the inflammatory grade, fibrosis stage and ALT levels. Most patients who loose e antigen have a decline in DNA load to below 5 log10 copies/ml. Further prospective studies employing repeated measurements are required to define a threshold to differentiate between HBV carriers and e antigen negative CHB.

Cloning and functional expression of an acyl-ACP thioesterase FatB type from Diploknema (Madhuca) butyracea seeds in Escherichia coli.

A cDNA of fatty acyl-acyl carrier protein (ACP) thioesterase (Fat) from developing seed of Madhuca butyracea has been cloned. The deduced amino acid sequence of the cDNA corresponding to the mature polypeptide showed 30-40% and 60-75% identity to the reported FatA and FatB class of plant thioesterases, respectively. This gene, MbFatB, is present as a single copy in M. butyracea genome and the MbFatB protein was detected clearly in seed tissues of this plant but not in that of Indian mustard (Brassica juncea). Heterologous expression of the MbFatB gene driven by different promoters in E. coli wild type and fatty acid beta-oxidation mutant (fadD88) strains resulted production of the recombinant protein with various fusion tags either as biologically inactive (insoluble) or functionally active forms. Expression of functionally active recombinant MbFatB in E. coli affected bacterial growth and cell morphology as well as changed the fatty acid profiles of the membrane lipid and the culture supernatant. Alteration of the fatty acid composition was directed predominantly towards palmitate and to a lesser extent myristate and oleate due to acyl chain termination activity of plant thioesterase in bacteria. Thus, this new MbFatB gene isolated from a non-traditional oil-seed tree can be used in future for transgenic development of oil-seed Brassica, a widely cultivated crop that expresses predominantly oleoyl-ACP thioesterase (FatA) in its seed tissue and has high amount of unwanted erucic acid in edible oil in order to alter the fatty acid profile in a desirable way.