<abstract xml:lang="en" xmlns="http://www.w3.org/1999/xhtml"><bold>Background.</bold> Testicular germ cell tumors (TGCTs) are the most frequent malignances in young adult men. The two main histological forms, seminomas and nonseminomas, differ biologically and clinically. pRB protein and its immediate upstream regulator p16INK4a are involved in the RB pathway which is deregulated in most TGCTs. The objective of this study was to evaluate the occurrence of loss of heterozygosity (LOH) of the <italic>CDKN2A (p16INK4a)</italic> and <italic>RB1</italic> tumor suppressor genes in TGCTs.<bold>Materials and methods.</bold> Forty TGCTs (18 seminomas and 22 nonseminomas) were analyzed by polymerase chain reaction using the restriction fragment length polymorphism or the nucleotide repeat polymorphism method.<bold>Results.</bold> LOH of the <italic>CDKN2A</italic> was found in two (6%) out of 34 (85%) informative cases of our total TGCT sample. The observed changes were assigned to two (11%) nonseminomas out of 18 (82%) informative samples. Furthermore, LOH of the <italic>RB1</italic> was detected in two (6%) out of 34 (85%) informative cases of our total TGCT sample. Once again, the observed changes were assigned to two (10.5%) nonseminomas out of 19 (86%) informative samples. Both LOHs of the <italic>CDKN2A</italic> were found in nonseminomas with a yolk sac tumor component, and both LOHs of the <italic>RB1</italic> were found in nonseminomas with an embryonal carcinoma component.<bold>Conclusions.</bold> The higher incidence of observed LOH in nonseminomas may provide a clue to their invasive behavior.</abstract>

Background. Testicular germ cell tumors (TGCTs) are the most frequent malignances in young adult men. The two main histological forms, seminomas and nonseminomas, differ biologically and clinically. pRB protein and its immediate upstream regulator p16INK4a are involved in the RB pathway which is deregulated in most TGCTs. The objective of this study was to evaluate the occurrence of loss of heterozygosity (LOH) of the CDKN2A (p16INK4a) and RB1 tumor suppressor genes in TGCTs.Materials and methods. Forty TGCTs (18 seminomas and 22 nonseminomas) were analyzed by polymerase chain reaction using the restriction fragment length polymorphism or the nucleotide repeat polymorphism method.Results. LOH of the CDKN2A was found in two (6%) out of 34 (85%) informative cases of our total TGCT sample. The observed changes were assigned to two (11%) nonseminomas out of 18 (82%) informative samples. Furthermore, LOH of the RB1 was detected in two (6%) out of 34 (85%) informative cases of our total TGCT sample. Once again, the observed changes were assigned to two (10.5%) nonseminomas out of 19 (86%) informative samples. Both LOHs of the CDKN2A were found in nonseminomas with a yolk sac tumor component, and both LOHs of the RB1 were found in nonseminomas with an embryonal carcinoma component.Conclusions. The higher incidence of observed LOH in nonseminomas may provide a clue to their invasive behavior.

Loss of heterozygosity of <italic>CDKN2A (p16INK4a)</italic> and <italic>RB1</italic> tumor suppressor genes in testicular germ cell tumors

Department of Biochemical Engineering, Faculty of Food Technology and Biotechnology, University of Zagreb, Zagreb, Croatia

Laboratory of Neurooncology, Croatian Institute for Brain Research, Department of Biology, School of Medicine, University of Zagreb, Zagreb, Croatia

Department of Oncology, Rebro University Hospital Center, Zagreb, Croatia

Ljudevit Jurak Department of Pathology, Sisters of Mercy University Hospital, Zagreb, Croatia

Radiology and Oncology

Loss of heterozygosity of  and  tumor suppressor genes in testicular germ cell tumors

Background. Testicular germ cell tumors (TGCTs) are the most frequent malignances in young adult men. The two main histological forms, seminomas and...

Loss of heterozygosity of CDKN2A (p16INK4a) and RB1 tumor suppressor genes in testicular germ cell tumors

Published Online: Aug 09, 2010

Page range: 168 - 173

DOI: https://doi.org/10.2478/v10019-010-0035-7

Keywords
loss of heterozygosity, CDKN2A, RB1, seminomas, nonseminomas

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