Tumorigenic potential of pituitary tumor transforming gene (PTTG) in vivo investigated using a transgenic mouse model, and effects of cross breeding with p53 (+/−) transgenic mice

BMC Cancer

Miranda Y Fong¹  Hanan Farghaly³  Sham S Kakar² 

[1] Department of Physiology and Biophysics, University of Louisville, 505 South Hancock Street, CTRB 322, Louisville, KY, 40202, USA

[2] Molecular Targets Program, James Graham Brown Cancer Center, University of Louisville, Louisville, KY, 40202, USA

[3] Department of Pathology, University of Louisville, Louisville, KY, 40202, USA

关键词: Cancer;    Tumorigenesis;    p53;    Transgenic mice;    PTTG;   

Others  :  1080079
DOI  :  10.1186/1471-2407-12-532

 received in 2012-05-16, accepted in 2012-11-08,  发布年份 2012

【 摘 要 】

Background

Pituitary tumor-transforming gene (PTTG) is an oncogene that is overexpressed in variety of tumors and exhibits characteristics of a transforming gene. Previous transgenic mouse models to access the tumorigenic potential in the pituitary and ovary have resulted in dysplasia without formation of visible tumors, possibly due to the insufficient expression of PTTG. PTTG expression level is critical for ovarian tumorigenesis in a xenograft model. Therefore, the tumorigenic function of PTTG in vivo remains unclear. We generated a transgenic mouse that overexpresses PTTG driven by the CMV promoter to determine whether PTTG functions as a transforming oncogene that is capable of initiating tumorigenesis.

Methods

Transgenic animals were generated by microinjection of PTTG transgene into the male pronucleus of FVB 0.5 day old embryos. Expression levels of PTTG in tissues of transgenic animals were analyzed using an immunohistochemical analysis. H&E staining and immunohistostaining were performed to examine the type of tumor in transgenic and PTTG transgenic/p53^+/- animals.

Results

PTTG transgenic offspring (TgPTTG) were monitored for tumor development at various ages. H&E analysis was performed to identify the presence of cancer and hyperplastic conditions verified with the proliferation marker PCNA and the microvessel marker CD31. Immunohistochemistry was performed to determine transgene expression, revealing localization to the epithelium of the fallopian tube, with more generalized expression in the liver, lung, kidney, and spleen. At eight months of age, 2 out of 15 TgPTTG developed ovarian cancer, 2 out of 15 developed benign tumors, 2 out of 15 developed cervical dysplasia, and 3 out of 15 developed adenomyosis of the uterus. At ten months of age, 2 out of 10 TgPTTG developed adenocarcinoma of the ovary, 1 out of 10 developed a papillary serous adenocarcinoma, and 2 out of 10 presented with atypia of ovarian epithelial cells. Tumorigenesis is a multi-step process, often requiring multiple oncogenes and/or inactivation of tumor suppressor genes. Therefore, to understand the contribution of p53 to PTTG induced tumorigenesis, we crossbred TgPTTG to p53^+/− mice and maintained those 8 to 10 months. TgPTTG/p53^+/− animals developed sarcomas faster than p53^+/− alone as well as different tumor types in addition to cervical carcinomas in situ in 10 out of 17 females.

Conclusions

We conclude that while PTTG is a functional transforming oncogene, it requires an additional partner to effectively promote tumorigenesis through the loss of p53 include or between function or modulation.

【 授权许可】

   
2012 Fong et al.; licensee BioMed Central Ltd.

【 图 表 】

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【 参考文献 】

• [1]Zou H, McGarry TJ, Bernal T, Kirschner MW: Identification of a vertebrate sister-chromatid separation inhibitor involved in transformation and tumorigenesis. Science 1999, 285:418-422.
• [2]Vlotides G, Eigler T, Melmed S: Pituitary tumor-transforming gene: physiology and implications for tumorigenesis. Endocr Rev 2007, 28:165-186.
• [3]Hamid T, Malik MT, Kakar SS: Ectopic expression of PTTG1/securin promotes tumorigenesis in human embryonic kidney cells. Mol Cancer 2005, 4:3. BioMed Central Full Text
• [4]Kim D, Pemberton H, Stratford AL, Buelaert K, Watkinson JC, Lopes V, Franklyn JA, McCabe CJ: Pituitary tumour transforming gene (PTTG) induces genetic instability in thyroid cells. Oncogene 2005, 24:4861-4866.
• [5]Kakar SS, Jennes L: Molecular cloning and characterization of the tumor transforming gene (TUTR1): a novel gene in human tumorigenesis. Cytogenet Cell Genet 1999, 84:211-216.
• [6]Heaney AP, Horwitz GA, Wang Z, Singson R, Melmed S: Early involvement of estrogen-induced pituitary tumor transforming gene and fibroblast growth factor expression in prolactinoma pathogenesis. Nat Med 1999, 5:1317-1321.
• [7]McCabe CJ, Boelaert K, Tannahill LA, Heaney AP, Stratford AL, Khaira JS, Hussain S, Sheppard MC, Franklyn JA, Gittoes NJ: Vascular endothelial growth factor, its receptor KDR/Flk-1, and pituitary tumor transforming gene in pituitary tumors. J Clin Endocrinol Metab 2002, 87:4238-4244.
• [8]Shah PP, Fong MY, Kakar SS: PTTG induces EMT through integrin alpha(V)beta(3)-focal adhesion kinase signaling in lung cancer cells. Oncogene 2011, 31:3124-3135.
• [9]Shah PP, Kakar SS: Pituitary tumor transforming gene induces epithelial to mesenchymal transition by regulation of Twist, Snail, Slug, and E-cadherin. Cancer Lett 2011, 311:66-76.
• [10]Pei L, Melmed S: Isolation and characterization of a pituitary tumor-transforming gene (PTTG). Mol Endocrinol 1997, 11:433-441.
• [11]Puri R, Tousson A, Chen L, Kakar SS: Molecular cloning of pituitary tumor transforming gene 1 from ovarian tumors and its expression in tumors. Cancer Lett 2001, 163:131-139.
• [12]McCabe CJ, Khaira JS, Boelaert K, Heaney AP, Tannahill LA, Hussain S, Mitchell R, Olliff J, Sheppard MC, Franklyn JA, Gittoes NJ: Expression of pituitary tumour transforming gene (PTTG) and fibroblast growth factor-2 (FGF-2) in human pituitary adenomas: relationships to clinical tumour behaviour. Clin Endocrinol (Oxf) 2003, 58:141-150.
• [13]Heaney AP, Melmed S: Pituitary tumour transforming gene: a novel factor in pituitary tumour formation. Baillieres Best Pract Res Clin Endocrinol Metab 1999, 13:367-380.
• [14]Heaney AP, Singson R, McCabe CJ, Nelson V, Nakashima M, Melmed S: Expression of pituitary-tumour transforming gene in colorectal tumours. Lancet 2000, 355:716-719.
• [15]Boelaert K, Tannahill LA, Bulmer JN, Kachilele S, Chan SY, Kim D, Gittoes NJ, Franklyn JA, Kilby MD, McCabe CJ: A potential role for PTTG/securin in the developing human fetal brain. FASEB J 2003, 17:1631-1639.
• [16]Solbach C, Roller M, Fellbaum C, Nicoletti M, Kaufmann M: PTTG mRNA expression in primary breast cancer: a prognostic marker for lymph node invasion and tumor recurrence. Breast 2004, 13:80-81.
• [17]Genkai N, Homma J, Sano M, Tanaka R, Yamanaka R: Increased expression of pituitary tumor-transforming gene (PTTG)-1 is correlated with poor prognosis in glioma patients. Oncol Rep 2006, 15:1569-1574.
• [18]Panguluri SK, Yeakel C, Kakar SS: PTTG: an important target gene for ovarian cancer therapy. J Ovarian Res 2008, 1:6. BioMed Central Full Text
• [19]El-Naggar SM, Malik MT, Kakar SS: Small interfering RNA against PTTG: a novel therapy for ovarian cancer. Int J Oncol 2007, 31:137-143.
• [20]Chesnokova V, Kovacs K, Castro AV, Zonis S, Melmed S: Pituitary hypoplasia in Pttg−/− mice is protective for Rb+/− pituitary tumorigenesis. Mol Endocrinol 2005, 19:2371-2379.
• [21]Cho-Rok J, Yoo J, Jang YJ, Kim S, Chu IS, Yeom YI, Choi JY, Im DS: Adenovirus-mediated transfer of siRNA against PTTG1 inhibits liver cancer cell growth in vitro and in vivo. Hepatology 2006, 43:1042-1052.
• [22]El-Naggar SM, Malik MT, Martin A, Moore JP, Proctor M, Hamid T, Kakar SS: Development of cystic glandular hyperplasia of the endometrium in Mullerian inhibitory substance type II receptor-pituitary tumor transforming gene transgenic mice. J Endocrinol 2007, 194:179-191.
• [23]Abbud RA, Takumi I, Barker EM, Ren SG, Chen DY, Wawrowsky K, Melmed S: Early multipotential pituitary focal hyperplasia in the alpha-subunit of glycoprotein hormone-driven pituitary tumor-transforming gene transgenic mice. Mol Endocrinol 2005, 19:1383-1391.
• [24]Zhang X, Horwitz GA, Prezant TR, Valentini A, Nakashima M, Bronstein MD, Melmed S: Structure, expression, and function of human pituitary tumor-transforming gene (PTTG). Mol Endocrinol 1999, 13:156-166.
• [25]Donangelo I, Gutman S, Horvath E, Kovacs K, Wawrowsky K, Mount M, Melmed S: Pituitary tumor transforming gene overexpression facilitates pituitary tumor development. Endocrinology 2006, 147:4781-4791.
• [26]Aiba-Masago S, Baba S, Li RY, Shinmura Y, Kosugi I, Arai Y, Nishimura M, Tsutsui Y: Murine cytomegalovirus immediate-early promoter directs astrocyte-specific expression in transgenic mice. Am J Pathol 1999, 154:735-743.
• [27]Kakar SS, Chen L, Puri R, Flynn SE, Jennes L: Characterization of a polyclonal antibody to human pituitary tumor transforming gene 1 (PTTG1) protein. J Histochem Cytochem 2001, 49:1537-1546.
• [28]Coltrera MD, Zarbo RJ, Sakr WA, Gown AM: Markers for dysplasia of the upper aerodigestive tract. Suprabasal expression of PCNA, p53, and CK19 in alcohol-fixed, embedded tissue. Am J Pathol 1992, 141:817-825.
• [29]Joshi M, Keith Pittman H, Haisch C, Verbanac K: Real-time PCR to determine transgene copy number and to quantitate the biolocalization of adoptively transferred cells from EGFP-transgenic mice. Biotechniques 2008, 45:247-258.
• [30]Jacks T, Remington L, Williams BO, Schmitt EM, Halachmi S, Bronson RT, Weinberg RA: Tumor spectrum analysis in p53-mutant mice. Curr Biol 1994, 4:1-7.
• [31]FVB.129S2(B6)-Trp53tm1Tyj/J.
• [32]Wang YK, Cui N, Li J, Luo B: Expression of pituitary tumor-transforming gene in endometrial carcinoma. Zhonghua Fu Chan Ke Za Zhi 2004, 39:538-542.
• [33]Kakar SS, Malik MT: Suppression of lung cancer with siRNA targeting PTTG. Int J Oncol 2006, 29:387-395.
• [34]Wang Z, Melmed S: Pituitary tumor transforming gene (PTTG) transforming and transactivation activity. J Biol Chem 2000, 275:7459-7461.
• [35]Li T, Jiang S: Effect of bFGF on invasion of ovarian cancer cells through the regulation of Ets-1 and urokinase-type plasminogen activator. Pharm Biol 2010, 48:161-165.
• [36]Ergin K, Gursoy E, Basimoglu Koca Y, Basaloglu H, Seyrek K: Immunohistochemical detection of insulin-like growth factor-I, transforming growth factor-beta2, basic fibroblast growth factor and epidermal growth factor-receptor expression in developing rat ovary. Cytokine 2008, 43:209-214.
• [37]Gabler C, Lauer B, Einspanier A, Schams D, Einspanier R: Detection of mRNA and immunoreactive proteins for acidic and basic fibroblast growth factor and expression of the fibroblast growth factor receptors in the bovine oviduct. J Reprod Fertil 1997, 109:213-221.
• [38]Luo CF, Hong HL, Lu YL, Wang H, Liu MQ: Expressions of bFGF and PTEN in cervical carcinoma and their clinical significance. Zhonghua Zhong Liu Za Zhi 2010, 32:533-538.
• [39]Jayshree RS, Sreenivas A, Tessy M, Krishna S: Cell intrinsic & extrinsic factors in cervical carcinogenesis. Indian J Med Res 2009, 130:286-295.
• [40]Sell S: On the stem cell origin of cancer. Am J Pathol 2010, 176:2584-2494.