A human pituitary adenoma cell line proliferates and maintains some differentiated functions following expression of SV40 large T-antigen

Jin, Long; Kulig, Elzbieta; Qian, Xiang; Scheithauer, Bernd W.; Eberhardt, Norman L.; Lloyd, Ricardo V.

doi:10.1007/bf02782609

Cited by 33 publications

(36 citation statements)

References 37 publications

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“…37 A measure of 1 mg total RNA was converted to cDNA using the Prostar First Strand RT-PCR Kit (Stratagene, La Jolla, CA, USA) according to the manufacturer's instruction. A measure of 5 ml cDNA was amplified by hot-start PCR in a GeneAmp PCR system 9700 (Applied Biosystems, Foster City, CA, USA).…”

Section: Rna Extraction and Rt-pcrmentioning

confidence: 99%

Role of COX-2, thromboxane A2 synthase, and prostaglandin I2 synthase in papillary thyroid carcinoma growth

et al. 2005

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The development of papillary thyroid carcinoma is influenced by many factors including genetic alterations, growth factors, and physical agents such as radiation. Arachidonic acid and its derivatives including prostaglandins (PG) and thromboxane along with the enzymes involved in their synthesis have been shown to influence the growth of various tumors. We analyzed the immunoreactivity for cyclooxygenase-2 (COX-2) and mRNA expression levels of the enzymes COX-2, thromboxane A 2 (TXA 2 ) synthase, and PGI 2 synthase by RT-PCR in papillary carcinomas and matching normal tissues to determine the role of these enzymes in the development of papillary thyroid carcinomas. A papillary thyroid carcinoma cell line TPC-1 was also studied in vitro to determine the role of the specific COX-2 inhibitor NS-398 on COX-2 and vascular endothelial growth factor-A, since COX-2 also has a role in regulating tumor angiogenesis. RT-PCR analysis showed significant increases in TXA 2 synthase mRNA levels in papillary thyroid carcinomas compared to normal thyroid tissues. Although COX-2 mRNA levels were generally increased in papillary carcinomas, the differences were not statistically significant. There were no significant differences in PGI 2 synthase mRNA levels. COX-2 protein expression was greater in papillary carcinoma compared to normal thyroid tissues; however, the levels were quite variable. In vitro studies with a COX-2 inhibitor, NS-398, showed inhibition of tumor growth along with increased levels of COX-2 and vascular endothelial growth factor-A mRNA expression. These results indicate that specific enzyme levels in the PG synthesis pathway such as TXA 2 synthase are increased in papillary thyroid carcinomas. COX-2 also has a role in papillary thyroid growth, since a specific inhibitor of COX-2 regulates papillary thyroid carcinoma cell proliferation. These results implicate several enzymes in the synthesis of prostanoids as regulators of thyroid papillary carcinoma proliferation and suggest that increased levels of expression of these enzymes may play a role in the pathogenesis of these tumors.

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Section: Rna Extraction and Rt-pcrmentioning

confidence: 99%

Role of COX-2, thromboxane A2 synthase, and prostaglandin I2 synthase in papillary thyroid carcinoma growth

et al. 2005

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“…25 Cells were treated with 1 mg/ml EGF (Promega, Madison, WI, USA) for 5 and 24 h and were then harvested. Proteins were extracted and used for Western blotting as described below.…”

Section: Cell Culturementioning

confidence: 99%

Analysis of epidermal growth factor receptor and activated epidermal growth factor receptor expression in pituitary adenomas and carcinomas

et al. 2004

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Epidermal growth factor receptor plays an important role in the pathogenesis of many malignancies. Various growth factors, including epidermal growth factor receptor, have been shown to influence pituitary tumor growth and differentiation. To analyze the role of epidermal growth factor receptor in pituitary tumor development, we examined normal pituitaries (n ¼ 8), pituitary adenomas (n ¼ 158), and pituitary carcinomas (n ¼ 7) for expression of epidermal growth factor receptor protein and messenger RNA using tissue microarrays and RT-PCR. We also examined (a) the expression of phospho-epidermal growth factor receptor, the activated form of epidermal growth factor receptor, in pituitary tumors and normal pituitaries by immunohistochemistry and (b) the effects on epidermal growth factor receptor expression of treating pituitary cells (HP75 cell line) with epidermal growth factor. Epidermal growth factor receptor and the phosphorylated variant expression were present in normal pituitary cells. Epidermal growth factor receptor messenger RNA was also detected in normal pituitaries, pituitary adenomas, and carcinomas by in situ hybridization and RT-PCR. Most pituitary adenomas showed expression of epidermal growth factor receptor and the phosphorylated variant. Nonfunctional adenomas showed higher levels of expression of epidermal growth factor receptor (76 vs 34%) and of phosphoepidermal growth factor receptor (26 vs 8%) as compared to functional adenomas. Five of seven pituitary carcinomas showed strong expression of both epidermal growth factor receptor and phospho-epidermal growth factor receptor. When a human pituitary cell line (HP75) was cultured in the presence of epidermal growth factor receptor, there was an increase in the levels of both epidermal growth factor receptor and phospho-epidermal growth factor receptor after 5 h of treatment, thus confirming that epidermal growth factor receptor signaling was active in pituitary tumors. These results indicate that activated epidermal growth factor receptor is expressed in pituitary adenomas and carcinomas. Higher levels in pituitary carcinomas suggest a role in pituitary tumor progression.

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“…Asterisks and diamonds indicate rearranged bands. The asterisks indicate the co-migrating bands detected by the IgH and w360 probes on HindIII digestion IgH/Lhx4 rearrangement in pre-B ALL N Kawamata et al pituitary adenoma (Jin et al, 1998), for Northern blot analysis and detected the transcript to be about 4.3 kb long (Figure 7a). To analyse the expression pattern of the Lhx4 gene in normal tissues, we performed Northern blotting and found no expression in any adult tissue examined (Figure 7b).…”

Section: Clinical Samplementioning

confidence: 99%

“…A human pituitary adenoma cell line, HP75 was provided from Dr RV Lloyd (Jin et al, 1998). Human leukemic cell lines, HL60 (myeloid), U937 (monocyte), K562 (erythroid), Jurkat (T-cell), Daudi, Raji (B-cell), HEK293 (embryoic kidney), A549 (Lung cancer), MCF7 (breast cancer) and SY5Y…”

Section: Rna Extraction Northern Blotting and Reverse Transcription mentioning

confidence: 99%

A novel chromosomal translocation t(1;14)(q25;q32) in pre-B acute lymphoblastic leukemia involves the LIM homeodomain protein gene, Lhx4

et al. 2002

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A human pituitary adenoma cell line proliferates and maintains some differentiated functions following expression of SV40 large T-antigen

Cited by 33 publications

References 37 publications

Role of COX-2, thromboxane A2 synthase, and prostaglandin I2 synthase in papillary thyroid carcinoma growth

Role of COX-2, thromboxane A2 synthase, and prostaglandin I2 synthase in papillary thyroid carcinoma growth

Analysis of epidermal growth factor receptor and activated epidermal growth factor receptor expression in pituitary adenomas and carcinomas

A novel chromosomal translocation t(1;14)(q25;q32) in pre-B acute lymphoblastic leukemia involves the LIM homeodomain protein gene, Lhx4

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