Short tandem repeat analysis to identify the causative pregnancy of high-risk gestational trophoblastic neoplasia: Molar versus nonmolar pregnancy and its relation to the outcome.

INTRODUCTION: Gestational trophoblastic neoplasia (GTN) include a group of malignant neoplasms that originate from the trophoblasts of placental tissue in molar or nonmolar pregnancy. Currently, it is unclear whether the prognosis of high-risk GTN or gestational choriocarcinoma succeeding molar pregnancy or that following a nonmolar one is better. Comparison of the genetic short tandem repeat (STR) patterns of the DNA extracted from the tumor, patient, and her partner allows the genetic origins of the choriocarcinoma to be distinguished - whether it is gestational or non-gestational and whether it is derived from a molar or nonmolar pregnancy in the event it is gestational. This study aimed to investigate the causative pregnancy of patients with high-risk GTN, especially those with poor outcomes, and assess the impact of the causative pregnancy on patient outcome. METHODS: We evaluated 24 patients who were diagnosed with high-risk GTN between January 2000 and October 2019, including 15 cases of pathologically proven gestational choriocarcinomas and the causative pregnancy was investigated by STR analysis in which tumor DNA could be extracted. RESULTS: In high-risk GTN without history of anteceding molar pregnancies, nonmolar pregnancy was the causative pregnancy, which was confirmed in three cases. Molar pregnancy appeared be the causative pregnancy of high-risk GTN in patients with a history of antecedent molar pregnancies either with or without interruption by subsequent nonmolar pregnancies prior to developing high-risk GTN. High-risk GTN in most of the evaluated deceased cases (three of four) was due to nonmolar pregnancy, while all but one case with molar pregnancy as the causative pregnancy survived. DISCUSSION: STR analysis can distinguish the causative pregnancy of high-risk GTN, and nonmolar pregnancy as the causative pregnancy might have negative effects on the outcome of the disease.

Next-generation genome sequencing of a matched normal-tumor pair from a patient with intractable gestational choriocarcinoma: A case report.

Gestational choriocarcinoma is a gestational trophoblastic neoplasia (GTN) originating from trophoblastic cells with abnormal proliferation. Although chemotherapy is effective for treating this cancer, when patients develop chemoresistance, personalized treatment, such as the use of drugs matching their genomes, is required. The present report describes a case of intractable gestational choriocarcinoma identified using a next-generation sequencing (NGS)-based tumor panel. A 51-year-old woman was diagnosed with gestational choriocarcinoma via pathological and short tandem repeat analyses. The patient did not achieve remission despite many regimens of chemotherapy, including high-dose therapy with autologous peripheral blood stem cell transplantation. To identify drugs tailored to this particular choriocarcinoma, NGS was performed on the tumor of the patient, and the tumor genome was compared with that of the patient's blood sample using the NCC Oncopanel System. Consequently, 245 single nucleotide variants (SNVs) with a mean SNV allele frequency of 63.1% were identified. This high frequency was because the genome of the gestational choriocarcinoma contained part of the genome of the partner. Therefore, our experience of the present intractable case of choriocarcinoma suggested that matched normal-tumor pair analysis is not appropriate for treatment decisions in GTN cases. When using an NGS-based tumor panel to assess choriocarcinoma, researchers must consider whether the genomic DNA of the patient and their partner are involved in the GTN.

A poor prognostic metastatic nongestational choriocarcinoma of the ovary: a case report and the literature review.

BACKGROUND: Pure ovarian choriocarcinoma can be gestational or nongestational in origin. Nongestational pure ovarian choriocarcinoma is extremely rare and the prognosis is thought to be worse than that of the gestational type in patients with metastatic disease. We present a case of metastatic pure ovarian choriocarcinoma with poor prognosis in which the origin was identified as nongestational by DNA short tandem repeat (STR) analysis. CASE PRESENTATION: A nulliparous woman in her thirties with metastatic choriocarcinoma was referred to our hospital after initial treatment proved unsuccessful. Two months earlier, she had undergone brain tumor resection and histological examination confirmed choriocarcinoma. Serum human chorionic gonadotropin (hCG) concentration at initial diagnosis was 5030 IU/L. Two cycles of a combination chemotherapy regimen of methotrexate, etoposide, and actinomycin-D (MEA therapy), which is commonly used for gestational choriocarcinoma, was administered. However, the disease could not be controlled. Imaging modalities at presentation revealed tumor present in the left ovary and left lung, but not in the uterus, which led us think that the choriocarcinoma was nongestational. Bleomycin, etoposide, and cisplatin (BEP therapy) which is commonly used for nongestational choriocarcinoma (malignant germ cell tumor) and surgical resection of the uterus, bilateral ovaries, and an affected part of the left lung led to the nadir level of hCG, but the tumor relapsed and levels of hCG again increased. To investigate the origin of choriocarcinoma, we performed DNA STR analysis of tumor cells and oral mucosal cells. Analysis revealed the origin of the choriocarcinoma as nongestational, as the genotype of tumor cells entirely corresponded with that of oral mucosal cells. BEP therapy and chemotherapy regimens administered for nongestational choriocarcinoma and gestational choriocarcinoma proved ineffective, and the patient died 21 months after diagnosis of metastatic choriocarcinoma. CONCLUSION: Metastaic nongestational pure choriocarcinoma of ovary is an extremely rare and an aggressive disease, frequently resulting in poor outcome.

Establishment and characterization of cell lines derived from complete hydatidiform mole.

Gestational trophoblastic diseases (GTDs) are a group of diseases characterized by abnormal cellular proliferation of atypical trophoblasts. A hydatidiform mole is an abnormal pregnancy caused by genetic fertilization disorders, and it can be classified as a complete hydatidiform mole (CHM) or a partial hydatidiform mole. The aim of this study was to establish cell lines from CHMs and to characterize the cells for future studies concerning GTD. HMol1-2C, HMol1-3B, HMol1-8 and HMol3-1B were established from primary cultures of CHM explants following the introduction of different combinations of genes including human telomerase reverse transcriptase (hTERT), a mutant form of CDK (CDK4R24C), cyclin D1, p53C234, MYC and HRAS. HMol1-2C, HMol1-3B, and HMol3-1B were confirmed to originate from trophoblasts of androgenic, homozygous CHMs. These three cell lines exhibited low human chorionic gonadotropin secretion, low migration and invasion abilities, and the potential to differentiate into syncytiotrophoblastic cells via forskolin treatment. These results suggest that these cells exhibit characteristics of trophoblastic cells, especially cytotrophoblastic cells. HMol1-8 was found to consist of diploid cells and originated from maternal cells, suggesting that they were derived from decidual cells. In conclusion, we successfully established three cell lines from CHMs by introduction of hTERT and other genes. Analysis revealed that the genetic origin of each cell line was identical with that of the original molar tissue, and the cell lines exhibited characteristics of trophoblastic cells, which are similar to undifferentiated cytotrophoblasts.

CD109 attenuates TGF-ß1 signaling and enhances EGF signaling in SK-MG-1 human glioblastoma cells.

CD109 is a glycosylphosphatidylinositol-anchored cell surface protein that is frequently detected in squamous cell carcinomas. CD109 is a negative regulator of TGF-ß1 signaling in human keratinocytes, and the N-terminal fragment of CD109 secreted from cells after cleavage by the furin protease is important for modulating TGF-ß1 signaling. Previously, we found that CD109 is expressed in human glioblastoma cells; however, the role of CD109 in glioblastoma cells is not established. Here, we describe the effects of CD109 in human glioblastoma cell lines. Three glioblastoma cell lines, SK-MG-1, U251MG and MG178, were tested and CD109 overexpression attenuated TGF-ß1 signaling and enhanced EGF signaling in SK-MG-1, but not in U251MG or MG178. The N-terminal CD109 fragment in SK-MG-1 was hyperglycosylated compared with that in MG178 or U251MG. The conditioned medium of CD109-overexpressing SK-MG-1, containing the secreted N-terminal CD109, had a negative effect on TGF-ß1 signaling in wild-type SK-MG-1 and MG178, whereas it did not show any effect on EGF signaling. In addition, cell surface CD109 interacts with EGF receptor in SK-MG-1 overexpressing CD109, and exhibited enhanced cell migration and invasion. These findings suggest that CD109 attenuates TGF-ß1 signaling and enhances EGF signaling in SK-MG-1 cells and that the membrane-anchored CD109 may play major roles in the EGF signaling pathway.

Identification of causative pregnancy of gestational trophoblastic neoplasia diagnosed during pregnancy by short tandem repeat analysis.

•Gestational trophoblastic neoplasia can arise during the first trimester originating from trophoblasts of concurrent pregnancy.•Intraplacental choriocarcinoma can be developed from trophoblasts of a previous pregnancy.

Ovarian mucinous tumors arising from mature cystic teratomas--a molecular genetic approach for understanding the cellular origin.

Mucinous tumors of the ovary are frequently associated with mature cystic teratomas, and it has been speculated that the mucinous tumors arise from teratoma components. The cellular origins of mature cystic teratomas are believed to be post-meiotic ovarian germ cells, and the analysis of microsatellite markers such as short tandem repeats is suitable for determining the cellular origin of tumors. In this study, we analyzed 3 ovarian mature cystic teratomas, all of which were associated with simultaneous ovarian mucinous tumors within the same ovary. Two of the 3 mucinous tumors were intestinal-type and the other was endocervical type. A laser capture microdissection technique was used to separate the epithelial component of the mucinous tumor, the components of the mature cystic teratoma, and control ovarian somatic tissue. Using short tandem repeat analysis based on 6 markers (D20S480, D6S2439, D6S1056, D9S1118, D4S2639, and D17S1290), we could distinguish the germ cell (homozygous) or somatic (heterozygous) origin of a given component in each sample. The epithelial components of the intestinal-type mucinous tumors in cases 1 and 2 were homozygous, and the epithelial component in case 3 (endocervical type) was heterozygous. All teratomatous components were homozygous, and the control components were heterozygous. In addition, we analyzed 3 mature cystic teratomas without mucinous tumors, and all 3 were homozygous in the tumor component. Our data suggest that the origin of mucinous tumors in the ovary may differ among histological subtypes, and intestinal-type mucinous tumors may arise from mature cystic teratomas, although endocervical-type mucinous tumors may not.

Genetically identified complete hydatidiform mole coexisting with a live twin fetus: comparison with conventional diagnosis.

Twin pregnancy consisting of a complete hydatidiform mole (CHM) along with a live co-existing fetus is a rare entity and difficult to diagnose. A 37-year-old Japanese woman demonstrated a living fetus, a placenta and a multicystic mass within one gestational sac on ultrasound at 10 weeks. Termination of the pregnancy was performed, and the specimen was classified as partial mole by macro- and microscopic findings. The karyotype of the molar tissue was 46XX. DNA polymorphism analysis demonstrated that fetal DNA showed bi-parental origin while molar DNA showed paternal origin only. Thus, this case was erroneously classified by ultrasonography, macroscopic and pathologic findings, then correctly diagnosed as a twin pregnancy with a CHM and co-existing normal twin fetus by DNA polymorphism analysis. Immunohistochemistry of p57(KIP2), the paternally imprinted and maternally expressed gene, supported the genetic diagnosis. This case suggested that conventional diagnostic methods were inadequate for accurate diagnosis of CHM with a co-existing fetus. DNA polymorphism analysis should be requested for the diagnosis of hydatidiform mole, especially in cases where it is difficult to discriminate between partial hydatidiform mole and CHM with a co-existing fetus.