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Abstract: The advent of transgenic technology has provided methods for the production of pharmaceuticals by the isolation of these proteins from transgenic animals. The mammary gland has been focused on as a bioreactor, since milk is easily collected from lactating animals and protein production can be expressed at very high levels, including hormones and enzymes. We demonstrate here the expression pattern of recombinant human growth hormone (rhGH) in transgenic rabbits carrying hGH genomic sequences driven by the rat whey acidic protein (WAP) promoter. The transgene was mapped to the q26-27 telomere region of chromosome 7q by fluorescence in situ hybridization (FISH). Nearly 30 % of the F1 generation demonstrated the presence of transgene. The recombinant growth hormone was detected in the milk of the transgenic rabbit females, but not in serum, up to the level of 10 μg/ml. Ectopic expression of the transgene in the brain, heart, kidney, liver, and salivary gland was not observed, indicating that a short sequence of rat WAP promoter (969 bp) contained essential sequences directing expression exclusively to the mammary gland. The biological activity of recombinant growth hormone was measured by immunoreactivity and the capability to stimulate growth of the hormone-dependent Nb211 cell line.

Abstract: Although down-regulation of GNG7 in cancer was reported before, its role in carcinogenesis is poorly understood. It belongs to a family of large G-proteins that may be involved in cell-contact-induced growth arrest and function in tumor suppression. In the present study, we stained immunohistochemically 188 tumors derived from larynx or floor of the mouth for GNG7 protein and confronted it with clinicopathologic data. Moreover, we performed bisulfite pyrosequencing to analyze GNG7 promoter methylation. We identified recurrent loss of GNG7 protein expression in 68/188 (36%) cases and promoter hypermethylation in (42/98; 43%) primary tumors, predominantly in young patients (p < 0.001). Loss of GNG7 expression correlated with hypermethylation of GNG7 promoter region (p < 0.001). Moreover, loss of GNG7 protein expression correlated with tumor size (p = 0.012) and lack of cervical metastasis (p = 0.02) whereas sustained expression correlated with keratinization (p = 0.008). Taken together, loss of GNG7 protein expression is a frequent event in head and neck cancer. Moreover, our data suggest that hypermethylation of the promoter region of GNG7 is probably the mechanism of the observed inactivation.