TY - JOUR
T1 - The oncogene Gankyrin is expressed in testicular cancer and contributes to cisplatin sensitivity in embryonal carcinoma cells
AU - Camacho-Moll, Maria E
AU - Macdonald, Joni
AU - Looijenga, L H J
AU - Rimmer, Michael P
AU - Donat, Roland
AU - Marwick, John A
AU - Shukla, C J
AU - Carragher, Neil
AU - Jørgensen, Anne
AU - Mitchell, Rod T
N1 - Publisher Copyright:
© 2019 The Author(s).
PY - 2019/11/19
Y1 - 2019/11/19
N2 - BACKGROUND: Testicular germ cell cancer (TGCC) develops from pre-malignant germ neoplasia in situ (GCNIS) cells. GCNIS originates from fetal gonocytes (POU5F1+/MAGE-A4-), which fail to differentiate to pre-spermatogonia (POU5F1-/MAGE-A4+) and undergo malignant transformation. Gankyrin is an oncogene which has been shown to prevent POU5F1 degradation and specifically interact with MAGE-A4 in hepatocellular carcinoma (HCC) cells. We aimed to investigate the role of Gankyrin in progression from gonocyte to pre-invasive GCNIS and subsequent invasive TGCC.METHODS: We determined Gankyrin expression in human fetal testicular tissue (gestational weeks 9-20; n = 38), human adult testicular tissue with active spermatogenesis (n = 9), human testicular tissue with germ cell maturation delay (n = 4), testicular tissue from patients with pre-invasive GCNIS (n = 6), and invasive TGCC including seminoma (n = 6) and teratoma (n = 7). Functional analysis was performed in-vitro by siRNA knock-down of Gankyrin in the NTera2 cells (derived from embryonal carcinoma).RESULTS: Germ cell expression of Gankyrin was restricted to a sub-population of prespermatogonia in human fetal testes. Nuclear Gankyrin was also expressed in GCNIS cells of childhood and adult pre-invasive TGCC patients, and in GCNIS from seminoma and non-seminoma patients. Cytoplasmic expression was observed in seminoma tumour cells and NTera2 cells. Gankyrin knock-down in NTera2 cells resulted in an increase in apoptosis mediated via the TP53 pathway, whilst POU5F1 expression was unaffected. Furthermore, Gankyrin knock-down in NTera2 cells increased cisplatin sensitivity with an increase in cell death (13%, p < 0.05) following Gankyrin knock-down, when compared to cisplatin treatment alone, likely via BAX and FAS. Our results demonstrate that Gankyrin expression changes in germ cells during normal transition from gonocyte to prespermatogonia. In addition, changes in Gankyrin localisation are associated with progression of pre-invasive GCNIS to invasive TGCC. Furthermore, we found that Gankyrin is involved in the regulation of NTera2 cell survival and that a reduction in Gankyrin expression can modulate cisplatin sensitivity.CONCLUSIONS: These results suggest that manipulation of Gankyrin expression may reduce the cisplatin dose required for the treatment of TGCC, with benefits in reducing dose-dependent side effects of chemotherapy. Further studies are required in order to assess the effects of modulating Gankyrin on GCNIS/TGCC using in vivo models.
AB - BACKGROUND: Testicular germ cell cancer (TGCC) develops from pre-malignant germ neoplasia in situ (GCNIS) cells. GCNIS originates from fetal gonocytes (POU5F1+/MAGE-A4-), which fail to differentiate to pre-spermatogonia (POU5F1-/MAGE-A4+) and undergo malignant transformation. Gankyrin is an oncogene which has been shown to prevent POU5F1 degradation and specifically interact with MAGE-A4 in hepatocellular carcinoma (HCC) cells. We aimed to investigate the role of Gankyrin in progression from gonocyte to pre-invasive GCNIS and subsequent invasive TGCC.METHODS: We determined Gankyrin expression in human fetal testicular tissue (gestational weeks 9-20; n = 38), human adult testicular tissue with active spermatogenesis (n = 9), human testicular tissue with germ cell maturation delay (n = 4), testicular tissue from patients with pre-invasive GCNIS (n = 6), and invasive TGCC including seminoma (n = 6) and teratoma (n = 7). Functional analysis was performed in-vitro by siRNA knock-down of Gankyrin in the NTera2 cells (derived from embryonal carcinoma).RESULTS: Germ cell expression of Gankyrin was restricted to a sub-population of prespermatogonia in human fetal testes. Nuclear Gankyrin was also expressed in GCNIS cells of childhood and adult pre-invasive TGCC patients, and in GCNIS from seminoma and non-seminoma patients. Cytoplasmic expression was observed in seminoma tumour cells and NTera2 cells. Gankyrin knock-down in NTera2 cells resulted in an increase in apoptosis mediated via the TP53 pathway, whilst POU5F1 expression was unaffected. Furthermore, Gankyrin knock-down in NTera2 cells increased cisplatin sensitivity with an increase in cell death (13%, p < 0.05) following Gankyrin knock-down, when compared to cisplatin treatment alone, likely via BAX and FAS. Our results demonstrate that Gankyrin expression changes in germ cells during normal transition from gonocyte to prespermatogonia. In addition, changes in Gankyrin localisation are associated with progression of pre-invasive GCNIS to invasive TGCC. Furthermore, we found that Gankyrin is involved in the regulation of NTera2 cell survival and that a reduction in Gankyrin expression can modulate cisplatin sensitivity.CONCLUSIONS: These results suggest that manipulation of Gankyrin expression may reduce the cisplatin dose required for the treatment of TGCC, with benefits in reducing dose-dependent side effects of chemotherapy. Further studies are required in order to assess the effects of modulating Gankyrin on GCNIS/TGCC using in vivo models.
KW - Apoptosis/genetics
KW - Biomarkers, Tumor
KW - Cell Cycle/genetics
KW - Cell Line, Tumor
KW - Cisplatin/pharmacology
KW - Drug Resistance, Neoplasm/genetics
KW - Gene Expression Regulation, Neoplastic
KW - Gene Knockdown Techniques
KW - Humans
KW - Immunohistochemistry
KW - Male
KW - Neoplasms, Germ Cell and Embryonal/genetics
KW - Oncogenes
KW - Proteasome Endopeptidase Complex/genetics
KW - Proto-Oncogene Proteins/genetics
KW - Testicular Neoplasms/genetics
UR - http://www.scopus.com/inward/record.url?scp=85075285362&partnerID=8YFLogxK
U2 - 10.1186/s12885-019-6340-7
DO - 10.1186/s12885-019-6340-7
M3 - Article
C2 - 31744479
SN - 1471-2407
VL - 19
SP - 1124
JO - BMC cancer
JF - BMC cancer
IS - 1
M1 - 1124
ER -