Differential gene expression of ligninolytic enzymes in Pleurotus ostreatus grown on olive oil mill wastewater.

The expression of laccase and manganese peroxidase genes of a selected strain of Pleurotus ostreatus were studied in olive oil mill wastewater (OMW). The fungal strain decolourized 50% OMW in a linear way for 21 days and, at the same time, degraded the phenol compounds by 85%. Transcripts of laccase genes poxa1b, pox2, poxa3, and sspoxa3a, sspoxa3b coding for the small subunits of POXA3, were estimated by qRT-PCR, at different time intervals, together with beta-tubulin gene used as internal control, from fungal cultures grown in a chemically-defined complete medium (CM), a supplemented CM with the addition of Cu(+2) and Mn(+2) (CM-plus) and 50% OMW in distilled water. The most abundant transcripts in both OMW and CM-plus were those of the poxa3, whereas pox2 transcripts were induced only in OMW and those of poxa1b at a strict time-window (14 days) in both OMW and CM-plus. Interestingly enough, the transcripts of genes sspoxa3a and sspoxa3b were up-regulated between 14-21 days, at a time at which the large subunit of the enzyme coded by poxa3 was down-regulated. The manganese peroxidase gene mnp2 exhibited a strong and specific transcriptional induction in OMW after 12 and 14 days, followed by a drastic drop after 18 days and a complete cease of expression at day 21, whereas mnp3 transcripts were at maximum level in OMW at day 10 but where thereafter reduced.

Mononucleotide markers of microsatellite instability in carcinomas of the urinary bladder.

AIMS: To determine the presence of microsatellite instability (MSI) and to assess the expression of the human mismatch repair (MMR) gene products hMLH1 and hMSH2 in primary transitional cell carcinomas (TCCs) of the urinary bladder in relation to clinico-pathological parameters. METHODS: Seventy-two cases of primary TCC were screened for the presence of alterations in MSI markers by molecular techniques and evaluated immunohistochemically for the expression of hMLH1 and hMSH2 proteins. Clinical data were available in 70 cases. The percentage of MSI rose to 16.6%. RESULTS: Reduced (<20%) hMLH1 expression was closely related to the presence of MSI (p=0.0004). Neither MMR proteins nor MSI was associated with grade, stage, papillary status. Clinical outcome analysed as a function of MSI did not show significant differences in terms of both disease-free and overall survival. Reduced hMLH1 expression was a significant predictor of shorter disease-free survival in univariate and multivariate analysis. CONCLUSIONS: The presence of MSI is not related to classical clinico-pathological parameters in TCCs, nor does it appear to be of prognostic significance. hMLH1 was an important indicator for recurrence.

p53 mutations detection in urinary bladder cancer in the Greek population: application of the NIRCA assay.

The aim of the present study was to assess the use of an alternative molecular approach for p53 mutation detection and to investigate the usefulness of p53 as a prognostic indicator in bladder cancer. We applied the NIRCA assay, which consists of two-step PCR amplification, transcription of the amplified sequence, hybridisation of the transcripts and treatment with RNAses which recognizes mismatches due to the presence of mutations. Results of molecular analysis are correlated with immunohistochemical findings, standard clinopathological parameters and survival. p53 mutations were detected in 42.4% of the 66 examined TCCs cases. We could not demonstrate any statistical relationship between the presence of p53 mutation and p53 protein overexpression, and tumor stage or grade. A trend towards higher mutation rate in higher grade tumours was observed, although this failed to reach statistical significance. Despite the observation that the alterations of p53 gene are associated features of aggressive phenotype of transitional cell carcinomas they do not seem to offer additional prognostic information.