Expression status of UBE2Q2 in colorectal primary tumors and cell lines

Background: Activation of the ubiquitin-proteasome pathway in various malignancies, including colorectal cancer, is established. This pathway mediates the degradation of damaged proteins and regulates growth and stress response. The novel human gene, UBE2Q2, with a putative ubiquitin-conjugating enzyme activity, is reported to be overexpressed in some malignancies. We sought to investigate the expression levels of the UBE2Q2 gene in colorectal cell lines as well as in cancerous and normal tissues from patients with colorectal cancer

Methods: Levels of UBE2Q2 mRNA in cell lines were assessed by Real-Time PCR. Western blotting was employed to investigate the levels of the UBE2Q2 protein in 8 colorectal cell lines and 43 colorectal tumor samples

Results: Expression of UBE2Q2 was observed at the level of both mRNA and protein in colorectal cell lines, HT29/219, LS180, SW742, Caco2, HTC116, SW48, SW480, and SW1116. Increased levels of UBE2Q2 immunoreactivity was observed in the 65.11% [28 out of 43] of the colorectal carcinoma tissues when compared with their corresponding normal tissues. Difference between the mean intensities of UBE2Q2 bands from cancerous and normal tissues was statistically significant at P<0.001 [paired t test]

Conclusion: We showed the expression pattern of the novel human gene, UBE2Q2, in 8 colorectal cell lines. Overexpression of UBE2Q2 in the majority of the colorectal carcinoma samples denotes that it may have implications for the pathogenesis of colorectal cancer

Quantitative analysis of ErbB1 and ErbB2 genes amplification by a high performance liquid chromatography

Genes for human epidermal growth factor receptors B1 [ErbB1] and B2 [ErbB2] were amplified in breast and ovarian cancers. Both of them were associated with aggressive disease and worse prognosis. The ErbB1 or ErbB2 status of a tumor may provide an indication of the response to ErbB1 and ErbB2 -targeted therapies. For accurate and rapid assessment of amplification of ErbB1 and ErbB2 oncogenes, a High Performance Liquid Chromatography [HPLC] method was developed in this study. DNA was extracted from 30 primary breast tumors and 20 blood samples of healthy donors. ErbB1 and ErbB2 genes along with a reference gene were co-amplificated by Polymerase Chain Reaction [PCR]. The PCR products were separated and quantified using an anion- exchange column within 30 min and in a single step. Optimum resolution was obtained when a sodium chloride gradient and a column temperature of 35°C were used. The results of HPLC analysis of ErbB1 and ErbB2 PCR products were compared with real time PCR method as a gold standard test for 7 tumor samples. The proposed HPLC method was confirmed by real time PCR method. Twenty two and ten of the specimens in our breast cancer cohort showed more than a two-fold amplification of ErbB2 and ErbB1 oncogenes, respectively. Our results were confirmed by real time PCR and showed that HPLC method is a specific, cheap and clinically applicable analytical approach for assessment of ErbB1 and ErbB2 statuses in breast tumors

Expression of UBE2Q2, a putative member of the ubiquitin-conjugating enzyme family in pediatric acute lymphoblastic leukemia

Acute lymphoblastic leukemia [ALL] is a cancer of the white blood cells most commonly found in childhood with a peak incidence at 2-5 years of age. The ubiquitin degradation pathway facilitates degradation of damaged proteins and regulates the growth and stress response. This pathway is activated in various cancers, including ALL. It has been previously reported that the newly characterized human gene UBE2Q2, a putative member of the ubiquitin-conjugating enzyme family, is over-expressed in the tumor mass and invasive epithelium in head and neck squamous cell carcinoma and breast cancer. Here, we have used quantitative reverse transcriptase polymerase chain reaction [RT-PCR] to assess expression of the UBE2Q2 gene in bone marrow samples of 20 children with ALL. Whole blood samples of 20 normal children were used as control specimens. RT-PCR revealed the expression of UBE2Q2 mRNA in 80% of the bone marrow samples from ALL patients as well as in 85% of leukemic normal peripheral blood cells. According to the results of quantitative RT-PCR, the levels of UBE2Q2 mRNA expression in the bone marrow cells of 11 out of the 20 children with ALL [55%] were significantly higher [> 2-47 fold] than those in blood cells of normal children. Our data suggest that the newly characterized human gene, UBE2Q2, may have implications for the pathogenesis of ALL and could be used for molecular diagnosis purposes in the future