HSD3B1 is a specific trophoblast-associated marker not expressed in a wide spectrum of tumors

Morphological Diversity of the Endometrium in Choriocarcinoma Specimens and its Role in Differential Diagnosis

Introduction: The morphological characteristics of the endometrium in patients with choriocarcinoma have not been well described. We described the endometrial morphology patterns in 46 choriocarcinomas and analyzed their relationship with the clinicopathological characteristics of these patients. Methods: Forty-six patients diagnosed with choriocarcinoma that had sufficient endometrial tissues for histopathological diagnosis were selected. Diagnoses of choriocarcinoma and secretory status of endometrium were reviewed. LHCGR expression of endometrium was evaluated by immunostaining. Results: Endometrial morphology was classified as secretory or nonsecretory. The 15 secretory specimens included 2 highly secretory and 13 common secretory specimens. The 31 nonsecretory patterns included 1 hyperplasia without atypia, 7 disordered proliferations, 13 typical proliferations, and 10 resting endometria. Among these, 11 specimens with overall nonsecretory patterns showed focally weak secretory changes surrounding the choriocarcinoma lesion. Secretory patterns were observed in classic choriocarcinomas (8/17) and monomorphic choriocarcinomas (7/21) but not in scanty-trophoblast choriocarcinomas (0/8). Secretory changes appeared significantly less frequently in patients who received multi-agent chemotherapy (4/25) than in those who did not (7/14) or received single-agent chemotherapy (4/7) (P = 0.030). The differences in age, months since the last pregnancy, pregnancy type, recurrence, specimen type, gross diameter, human chorionic gonadotropin (hCG) levels, and expression of hCG receptors were not statistically significant. Conclusions: The endometrial morphologies in choriocarcinoma were diverse, including various proliferative and secretory changes, but rarely hypersecretory changes, compared to the prevailing hypersecretory endometrium in hydatidiform moles. The variety in endometrial morphology was the consequence of ovarian hormonal disturbances of the hypothalamic-pituitary-gonadal axis by hCG from choriocarcinoma. Therefore, the endometrium may serve as a clue for histopathological diagnosis of choriocarcinoma. Our study presents the largest cohort reported to date to describe the diverse spectrum of endometrial changes in choriocarcinoma patients.

Non-gestational choriocarcinoma: unraveling the similarities and distinctions from its gestational counterpart

Choriocarcinoma is a highly vascular and invasive tumor of anaplastic trophoblast, predominantly made up of cytotrophoblasts and syncytiotrophoblasts without villi. Based on its origin, choriocarcinoma can be either gestational or non-gestational. Non-gestational choriocarcinoma can be of germ cell origin, or can be seen in association with a somatic high-grade malignancy. It is difficult to differentiate gestational from non-gestational choriocarcinoma, especially in the reproductive age group. It is important to distinguish between the two, for accurate staging and prognostication, deciding the primary treatment modality, (ie, surgery or chemotherapy), and tailoring follow-up timeframes after diagnosis. An extensive literature search was performed regarding all cases of non-gestational choriocarcinoma, published before March 2023. A note was made of whether the origin of choriocarcinoma was ascertained and how gestational choriocarcinoma was differentiated from non-gestational choriocarcinoma. The keywords used for literature search were "non-gestational choriocarcinoma", "primary choriocarcinoma", "ovarian choriocarcinoma", "ovarian germ cell tumors", or "choriocarcinomatous differentiation". This review aims to summarize the similarities and differences in the epidemiology, pathogenesis, clinical presentation, and management guidelines between gestational and non-gestational choriocarcinoma, which can form an important educational resource for clinicians and laboratory physicians dealing with such cases.

Trilostane, a 3β-hydroxysteroid dehydrogenase inhibitor, suppresses growth of hepatocellular carcinoma and enhances anti-cancer effects of sorafenib

Background Human 3β-hydroxysteroid dehydrogenase type 1 (HSD3B1) is an enzyme associated with steroidogenesis, however its' role in hepatocellular carcinoma (HCC) biology is unknown. Trilostane is an inhibitor of HSD3B1 and has been tested as a treatment for patients with breast cancer but has not been studied in patients with HCC. Methods and Results The expression of HSD3B1 in HCC tumors in 57 patients were examined. A total of 44 out of 57 tumors (77.2%) showed increased HSD3B1 expression. The increased HSD3B1 in tumors was significantly associated with advanced HCC. In vitro, the knockdown of HSD3B1 expression in Mahlavu HCC cells by a short hairpin RNA (shRNA) led to significant decreases in colony formation and cell migration. The suppression of clonogenicity in the HSD3B1-knockdown HCC cells was reversed by testosterone and 17β-estradiol. Trilostane-mediated inhibition of HSD3B1 in different HCC cells also caused significant inhibition of clonogenicity and cell migration. In subcutaneous HCC Mahlavu xenografts, trilostane (30 or 60 mg/kg, intraperitoneal injection) significantly inhibited tumor growth in a dose-dependent manner. Furthermore, the combination of trilostane and sorafenib significantly enhanced the inhibition of clonogenicity and xenograft growth, surpassing the effects of each drug used alone, with no documented additional toxicity to animals. HSD3B1 blockade was found to suppress the phosphorylation of extracellular signal-regulated kinase (ERK). The decreased ERK phosphorylation was reversed by testosterone or 17b-estradiol. Conclusions Trilostane significantly inhibited the growth of HCC by inhibiting HSD3B1 function and augmenting the efficacy of sorafenib.

Whole transcriptome analysis of gestational trophoblastic neoplasms reveals altered PI3K signaling pathway in epithelioid trophoblastic tumor

OBJECTIVE

Genomic characteristics of gestational trophoblastic neoplasm (GTN) are mostly unknown. This study reveals the molecular features of malignant GTN, including choriocarcinoma (CC), epithelioid trophoblastic tumor (ETT), and placental site trophoblastic tumor (PSTT), by whole transcriptome sequencing analysis.

METHODS

Data obtained from the total RNA sequencing of 2 CC, 4 ETT, and 4 PSTT were evaluated for differential gene expression, pathway alteration, fusion gene, infiltrating immune cell type, PD-L1 and PTEN expression level, and mutation analysis was performed.

RESULTS

The transcriptome data were correlated with known biomarkers, including HDS3B1, p63, hCG, and hPL for all tumor types. ETT and PSTT were more closely clustered compared with CC in clustering analysis using gene expression; however, ETT showed various altered signaling pathways, including PI3K-Akt-mTOR, with frequent loss of PTEN protein expression. This finding was both well correlated with PIK3CA c.3140A > G pathogenic mutation, detected in 1 ETT, and further confirmed using the MassARRAY method. PSTT showed an overexpressed gene cluster associated with muscle contraction and G protein-coupled receptor activity. No significant fusion gene was seen in all 10 cases. In tumor-infiltrating immune cell profiles, CD4 memory T cell and macrophage signature were relatively high in ETT and PSTT. PD-L1 mRNA expression level was high in all cases, which was significantly correlated with the PD-L1 level by immunohistochemistry (p = 0.03) with positivity in all 10 cases.

CONCLUSIONS

ETT and PSTT were similar at the transcriptome level, with a high level of PD-L1 expression in all tumor types; however, specific pathways, such as PI3K signaling, were altered in ETT.

Transcriptomic features of trophoblast lineage cells derived from human induced pluripotent stem cells treated with BMP 4

INTRODUCTION

Early development of the human placenta remains poorly understood due to the lack of proper model systems. Previous reports have demonstrated that human induced pluripotent stem cells (hiPSCs) treated with bone morphogenetic protein 4 (BMP4) can differentiate into extraembryonic tissues as useful models of the early stage of trophoblast (TB) differentiation. In our previous study, we optimized the culture conditions of hiPSC-derived TB lineages, but the differentiated cells were heterogeneous.

METHODS

In order to characterize the hiPSC-derived TB lineage cells, four types of hiPSCs were treated with 50 ng/mL of BMP4 for 10 days. Subsequently, cells that were positive for the pan-TB marker keratin 7(KRT7) were purified from the differentiated cells using flow cytometry and identified with a DNA microarray.

RESULTS

Comparisons of our microarray data with the human transcriptome in a previous large-scale analysis showed that the gene expression patterns of KRT7+ cells were similar to the placenta. In total, 259 upregulated genes were commonly expressed in all four KRT7+ groups, including well-known TB markers. Among these upregulated genes, several with poorly investigated expression patterns and functions were confirmed as expressed in the primary placenta. While only XAGE2 and KCNQ2 were expressed in TB layers, XAGE2 was expressed throughout pregnancy and KCNQ2 was expressed only in cytotrophoblasts of the first trimester placenta.

CONCLUSION

BMP4-treated KRT7+ cells were in the course of the human placental development. In addition, this approach allowed the identification of new genes that might be involved in placentation. However, further studies are needed to confirm their functions.

Gene expression patterns associated with human placental trophoblast differentiation

Cell fusion is a hallmark of placental trophoblast cell differentiation and the mature syncytiotrophoblasts play essential roles for fetal-maternal exchange and production of pregnancy-related hormones. Using a well-established in vitro trophoblast differentiation model, we performed a microarray analysis on mRNA expression in trophoblast and syncytiotrophoblast cell cultures. Dramatic changes in gene expression patterns were detected during trophoblast differentiation. Real-time PCR analysis confirmed the reliability of the microarray data. As many as 3524 novel and known genes have been found to be up- or down-regulated for >2-fold. A number of cell cycle regulator including CDC6, CDC20, Cyclins B2, L1 and E2, were down-regulated in the syncytiotrophoblast, providing a mechanism for the loss of mitotic activity during trophoblast differentiation. Further characterization on the identified genes may lead to better understanding of placental patho-physiology in obstetric diseases such as preeclampsia.

Transcriptome analysis revealed the possible regulatory pathways initiating female geese broodiness within the hypothalamic-pituitary-gonadal axis

Geese have the strongest tendency toward broodiness among all poultry. The mechanisms initiating broodiness within the goose hypothalamic-pituitary-gonadal axis (HPGA) are still unclear. Here, we reported the transcriptome differences between laying and initial nesting within the HPGA tissues of geese. We constructed a unigene database based on HPGA tissues and identified 128,148 unigenes, 100% of which have been annotated. By using Digital Gene Expression (DGE) sequencing, we screened 19, 110, 289, and 211 differentially expressed genes (DEGs) in the hypothalamus, pituitary gland, stroma ovarii, and follicles, respectively, between laying and nesting geese. Expression changes of hypocretin (HCRT) and pro-opiomelanocortin (POMC) in the hypothalamus of nesting geese may cause appetite reduction, which is possibly the first step and a prerequisite to initiate broodiness. In addition to prolactin (PRL), follicle-stimulating hormone (FSH) and luteinizing hormone (LH), genes including oxytocin-neurophysin (OXT), chordin-like protein 1 (CHRDL1) and growth hormone (GH), expressed in the pituitary gland, are new candidate molecules that may be involved in broodiness in geese. Heme oxygenase 1 (HMOX1) in the pituitary gland, the proto-oncogene c-Fos (FOS), heat shock protein 90-alpha (HSP90AA), and cyclin-dependent kinase 1 (CDK1) in the ovary that may consolidate and transduce signals regulating the HPGA during broodiness in geese.

Translational Research in Pediatrics IV: Solid Tissue Collection and Processing

Solid tissues are critical for child-health research. Specimens are commonly obtained at the time of biopsy/surgery or postmortem. Research tissues can also be obtained at the time of organ retrieval for donation or from tissue that would otherwise have been discarded. Navigating the ethics of solid tissue collection from children is challenging, and optimal handling practices are imperative to maximize tissue quality. Fresh biopsy/surgical specimens can be affected by a variety of factors, including age, gender, BMI, relative humidity, freeze/thaw steps, and tissue fixation solutions. Postmortem tissues are also vulnerable to agonal factors, body storage temperature, and postmortem intervals. Nonoptimal tissue handling practices result in nucleotide degradation, decreased protein stability, artificial posttranslational protein modifications, and altered lipid concentrations. Tissue pH and tryptophan levels are 2 methods to judge the quality of solid tissue collected for research purposes; however, the RNA integrity number, together with analyses of housekeeping genes, is the new standard. A comprehensive clinical data set accompanying all tissue samples is imperative. In this review, we examined: the ethical standards relating to solid tissue procurement from children; potential sources of solid tissues; optimal practices for solid tissue processing, handling, and storage; and reliable markers of solid tissue quality.

GATA-3 expression in trophoblastic tissues: an immunohistochemical study of 445 cases, including diagnostic utility

Immunohistochemical expression of GATA-3 is seen predominantly in non-neoplastic bladder and breast epithelium and their respective carcinomas; however, data on expression in normal and lesional trophoblastic tissues are limited. Immunohistochemical staining for GATA-3 was assessed in a range of normal/lesional trophoblastic tissues and tumors in the differential diagnosis (n=445), including nonmolar products of conceptions/second and third trimester placentas/ectopic pregnancies, hydatidiform moles, placental site nodules, normal/exaggerated implantation sites, choriocarcinomas, epithelioid trophoblastic tumors, placental site trophoblastic tumors, atypical smooth muscle tumors (including leiomyosarcoma), and cervical and pulmonary squamous cell carcinomas. The extent of expression (0 to 4+) and intensity (weak to strong) were recorded. All cases with developing trophoblast/non-neoplastic trophoblastic proliferation and 81% of trophoblastic neoplasms were positive. Of all non-neoplastic trophoblast cell types, expression was observed in cytotrophoblast in 89% of cases, syncytiotrophoblast in 50%, intermediate trophoblast in 100%, and villous trophoblastic columns in 100%. Increasing gestational age was associated with a decrease in extent/intensity of expression in non-neoplastic cytotrophoblast and syncytiotrophoblast, whereas intermediate trophoblast maintained diffuse and strong expression from early to late gestation (P<0.0001). Eighty-nine percent of normal/exaggerated implantation sites showed 3+ or 4+ expression, whereas staining in 55% of placental site nodules was 1+ or 2+. Staining for GATA-3 was present in 78% of choriocarcinomas, 95% of epithelioid trophoblastic tumors, and 71% of placental site trophoblastic tumors. Although the number of choriocarcinomas and placental site trophoblastic tumors that showed a spectrum of expression ranging from negative to diffuse was relatively evenly distributed, 81% of epithelioid trophoblastic tumors had 3+ or 4+ staining. None of the atypical smooth muscle tumors and 3% of squamous cell carcinomas were positive, all of which exhibited weak staining. We conclude that GATA-3 is frequently expressed in normal and lesional trophoblastic tissues. It is also differentially expressed in intermediate trophoblast and cytotrophoblast/syncytiotrophoblast, which varies according to time during pregnancy. This study expands the spectrum of neoplasms known to express GATA-3. Thus, recognition of expression in trophoblastic tumors is important, because it can present a diagnostic pitfall in the assessment of suspected metastatic bladder or breast carcinomas involving the gynecologic tract. In the evaluation of diagnostically problematic tumors for which trophoblastic neoplasms are in the differential diagnosis, such as leiomyosarcoma and squamous cell carcinoma, GATA-3 can be included as part of an immunohistochemical panel particularly when other trophoblastic markers are either not available or yield ambiguous results.

KSHV microRNAs mediate cellular transformation and tumorigenesis by redundantly targeting cell growth and survival pathways

Kaposi's sarcoma-associated herpesvirus (KSHV) is causally linked to several human cancers, including Kaposi's sarcoma, primary effusion lymphoma and multicentric Castleman's disease, malignancies commonly found in HIV-infected patients. While KSHV encodes diverse functional products, its mechanism of oncogenesis remains unknown. In this study, we determined the roles KSHV microRNAs (miRs) in cellular transformation and tumorigenesis using a recently developed KSHV-induced cellular transformation system of primary rat mesenchymal precursor cells. A mutant with a cluster of 10 precursor miRs (pre-miRs) deleted failed to transform primary cells, and instead, caused cell cycle arrest and apoptosis. Remarkably, the oncogenicity of the mutant virus was fully restored by genetic complementation with the miR cluster or several individual pre-miRs, which rescued cell cycle progression and inhibited apoptosis in part by redundantly targeting IκBα and the NF-κB pathway. Genomic analysis identified common targets of KSHV miRs in diverse pathways with several cancer-related pathways preferentially targeted. These works define for the first time an essential viral determinant for KSHV-induced oncogenesis and identify NF-κB as a critical pathway targeted by the viral miRs. Our results illustrate a common theme of shared functions with hierarchical order among the KSHV miRs.

Kaposi's sarcoma-associated herpesvirus (KSHV) is the causal agent of several human cancers. KSHV encodes over two dozen genes that regulate diverse cellular pathways. However, the molecular mechanism of KSHV-induced oncogenesis remains unknown. In this study, we determined the roles of KSHV microRNAs (miRs) in KSHV-induced oncogenesis using a recently developed KSHV cellular transformation system of primary rat mesenchymal precursor cells. A KSHV mutant with a cluster of 10 precursor miRs (pre-miRs) deleted failed to transform primary cells, and instead, caused cell cycle arrest and apoptosis. Expression of the miR cluster or several pre-miRs was sufficient to restore the oncogenicity of the mutant virus. KSHV miRs regulated cell cycle progression and inhibited apoptosis in part by redundantly targeting IκBα and the NF-κB pathway. By integrating gene expression profiling and target prediction, we identified common targets of KSHV miRs in diverse pathways. Importantly, several cancer-related pathways were preferentially targeted by KSHV miRs. These works have demonstrated for the first time the important roles of KSHV miRs in oncogenesis and identified NF-κB as a critical pathway targeted by the miRs. Our results reveal that shared function is a common theme of KSHV miRs, which manifest functional hierarchical order.