Encounter with Huge Yolk Sac Ovarian Tumor in a Child: A Case Report.

Yolk sac tumour frequently arises in the gonads as a type of germ cell tumour, though rare is a highly malignant ovarian tumour in children and prompt treatment should be done. We hereby report a case of malignant ovarian tumour presenting with an abdominal lump and increased urinary frequency. Different diagnostic modalities were used such as ultrasonography of the whole abdomen, contrast-enhanced computed tomography abdomen pelvis and tumour markers of beta-human chorionic gonadotropin and alpha-fetoprotein. This revealed an 18.2x14.3x10 cm mass likely a neoplastic germ cell tumour with minimal ascites. A tumour mass was found to arise from the left ovary and complete excision of the tumour along the left fallopian tube was done. Adjuvant chemotherapy started immediately. We hereby present a case of a 9-year-old girl with a huge yolk sac tumour of the left ovary which is rare in our setting and is presented here to differentiate any ovarian mass in this age group. Keywords: children; surgical procedure; yolk sac tumour.

Pediatric Primary Yolk Sac Tumour of the Kidney: Recommendations for Pretreatment Diagnosis.

Introduction Although nephroblastomas are frequently treated without prior biopsy, there are the occasional other pediatric renal tumors that require different management. In the literature, there are around 30 primary renal germ cell tumors (GCT), including four cases of Yolk sac tumor (YST). We present another primary renal YST.Case report: A five-year-old boy was diagnosed as Wilms tumor on radiology and needle biopsy. He received chemotherapy, with no response. The post-chemotherapy resection specimen revealed a YST.Conclusion: Renal YST may be indistinguishable from Wilms tumor clinically and radiologically. For pre-biopsy chemotherapy management protocols, serum tumor markers such as AFP may be recommended to identify the occasional GCT, including YST. Pre-chemotherapy needle biopsies may lead to misdiagnosis, and may require confirmation by an experienced pathologist or central review.

Pure post-pubertal yolk sac tumor of the testis: An extremely rare and aggressive entity.

CONTEXT: Pure post-pubertal yolk sac tumors (YSTs) are an extremely rare type of malignant germ cell tumor (GCT) that account for <1 % of testicular GCTs. Clinically, they are more aggressive compared to the more common pre-pubertal counterpart. The aim of this study is to analyze the clinical presentation, ancillary tests and clinical outcomes in addition to presenting a spectrum of histomorphological features, in a case series along with a literature review. DESIGN: A retrospective review of 4 cases of pure post-pubertal YST of the testis was performed. Data collected for each patient included demographics, clinical presentation, serum markers, radiology and pathologic findings, treatment, and clinical outcomes. RESULTS: All patients presented with a testicular mass with or without associated pain and elevated serum alpha-feto protein. Mean age at presentation was 36 years (range 25-68 years). Two patients presented with metastatic disease at the time of diagnosis. Histologic patterns and features are as follows: germ cell neoplasia in-situ (n = 4), reticular/microcystic, solid, glandular, papillary, endometrioid, cystic, necrosis and angiolymphatic invasion (n = 3). Fluorescent in-situ hybridization test performed on Case 2, showed presence of isochromosome 12p and next generation sequencing showed gains of 12p. Case 1, 2 and 4 showed metastatic disease on follow-up. CONCLUSIONS: Diagnosis of pure post-pubertal YST remains challenging due to the variety of morphologic patterns often present in these tumors. Extensive sampling along with use of ancillary tests is the key for diagnosis. In this study, 75 % of cases had metastatic disease at or after the diagnosis confirming the aggressive nature of this rare entity.

Yolk sac differentiation in urothelial carcinoma - A rare variant originating from aberrant differentiation of sarcomatoid components.

Yolk sac differentiation occurs in somatic neoplasms of the gastrointestinal and gynecologic tracts; it has rarely been reported in urothelial carcinoma. Here, we report three cases of yolk sac differentiation in sarcomatoid urothelial carcinoma. The epithelioid component of the sarcomatoid urothelial carcinoma showed divergent differentiation, including squamous, conventional glandular, small cell carcinoma, and yolk sac components. The sarcomatoid component showed malignant spindle cells admixed with focal chondroid and rhabdoid elements. In all three cases, the yolk sac areas were admixed with the sarcomatoid component and showed a glandular pattern, with vacuolated, eosinophilic cytoplasm. These areas were positive for SALL4, variably positive for glypican 3 and AFP, and negative for the conventional urothelial markers GATA3, p63, and 34ßE12. Yolk sac differentiation is an extremely rare occurrence in sarcomatoid urothelial carcinoma.

Yolk sac tumor of the uterus in a 2-year-old girl: A case report and literature review.

BACKGROUND: Extragonadal yolk sac tumors (YSTs) occurring in the uterus are extremely rare. To report a uterine YST case in a prepubertal girl and review literature on uterine YST to outline clinical management in diagnosis and treatment. CASE: We present a case of a 2-year-old girl who presented with vaginal bleeding and a pelvic mass. The diagnosis of YST was confirmed via biopsy. After four cycles of neoadjuvant chemotherapy combined with cisplatin, etoposide, and bleomycin (PEB), vaginoscopic examination and laparoscopy revealed a uterine YST without metastasis. The patient was treated with laparoscopic hysterectomy and two cycles of PEB postoperatively. During the 18 months of follow-up, the patient remained disease-free. SUMMARY AND CONCLUSION: Primary uterine YST is extremely rare and no treatment guidelines have been established to date. Surgery combined with PEB chemotherapy is considered effective for uterine YST.

Differences in Cell-Intrinsic Inflammatory Programs of Yolk Sac and Bone Marrow Macrophages.

BACKGROUND: Tissue-resident macrophages have mixed developmental origins. They derive in variable extent from yolk sac (YS) hematopoiesis during embryonic development. Bone marrow (BM) hematopoietic progenitors give rise to tissue macrophages in postnatal life, and their contribution increases upon organ injury. Since the phenotype and functions of macrophages are modulated by the tissue of residence, the impact of their origin and developmental paths has remained incompletely understood. METHODS: In order to decipher cell-intrinsic macrophage programs, we immortalized hematopoietic progenitors from YS and BM using conditional HoxB8, and carried out an in-depth functional and molecular analysis of differentiated macrophages. RESULTS: While YS and BM macrophages demonstrate close similarities in terms of cellular growth, differentiation, cell death susceptibility and phagocytic properties, they display differences in cell metabolism, expression of inflammatory markers and inflammasome activation. Reduced abundance of PYCARD (ASC) and CASPASE-1 proteins in YS macrophages abrogated interleukin-1ß production in response to canonical and non-canonical inflammasome activation. CONCLUSIONS: Macrophage ontogeny is associated with distinct cellular programs and immune response. Our findings contribute to the understanding of the regulation and programming of macrophage functions.

RISK FACTORS ASSOCIATED WITH YOLK SAC RETENTION IN CAPTIVE-BRED HUMBOLDT PENGUIN (SPHENISCUS HUMBOLDTI) CHICKS.

Multiple occurrences of yolk sac retention prompted a retrospective investigation in a recently formed colony of captive Humboldt penguins (Spheniscus humboldti). Necropsy reports of 141 parent-reared penguin chicks that died between January 2014 and December 2018 were reviewed for evidence of yolk sac retention, defined as the presence of a yolk sac at postmortem examination of a chick aged 7 d or greater, and analyzed by demographic and pathological variables for identification of risk factors. Fifty-nine (65%) chicks that died at age 7 d or greater had a retained yolk sac at postmortem examination, revealing that this was a common condition in penguins in this population. Chicks that retained their yolk sac were also more likely to present with minimal gut contents (P = 0.02), have a prominent bursa of Fabricius (P < 0.01), and be the first chick hatched of their clutch (P = 0.02). Parental experience and age were not predictive of yolk sac retention, but there was a trend for chicks with retained yolk sacs to present with a poorer body condition, reduced weight, and reduced crown-rump length compared to chicks without a retained yolk sac. Histopathological and bacteriological findings of retained yolk sacs were not significantly different from those of chicks under 7 d of age. Although likely to be multifactorial, the association between yolk sac retention and indicators of suboptimal feed intake and growth (empty gastrointestinal tract, poor body condition score, decreased crown-rump length, and decreased weight at death) is hypothesized to be a result of parental neglect, leading to starvation and absorption arrest of the yolk, as previously indicated in broiler chicks.

Somatically Derived Yolk Sac Tumor of the Ovary in a Young Woman.

Ovarian carcinoma with a somatically derived yolk sac tumor component is a phenomenon known to mostly occur in postmenopausal women. Herein, we report an ovarian endometriosis-associated somatic yolk sac tumor arising in the background of a low-grade endometrioid adenocarcinoma in a young woman. A 27-yr-old woman presented with abdominal pain, subsequently recognized to be caused by a right ovarian mass undergoing torsion. Following operative management, microscopic examination of the salpingo-oophorectomy specimen showed endometriosis and a predominantly cystic ovarian neoplasm with 2 distinct phenotypic areas: (1) a yolk sac tumor component containing Schiller-Duval bodies and (2) a low-grade endometrioid carcinoma component with squamous metaplasia. Immunohistochemical evaluation showed distinct profiles in the yolk sac tumor (estrogen receptor/progesterone receptor/PAX8 negative, SALL4/Glypican 3 positive) and endometrioid (estrogen receptor/progesterone receptor/PAX8 positive, SALL4/Glypican 3 negative) components. Given these findings, the diagnosis of an endometriosis-associated endometrioid adenocarcinoma with a somatically derived yolk sac tumor was rendered. The tumor was staged as pT1c1 due to intraoperative spillage. The patient underwent chemotherapeutic treatment and after 15 mo of follow-up, she was alive with no evidence of recurrence. This example demonstrates that somatic yolk sac tumor differentiation in ovarian epithelial neoplasia can occur in young patients; awareness of this phenomenon is important as somatic and germ cell yolk sac neoplasia have different behavior and therapy.

Dose-dependent Changes After Proton and Photon Irradiation in a Zebrafish Model.

BACKGROUND/AIM: The importance of hadron therapy in the cancer management is growing. We aimed to refine the biological effect detection using a vertebrate model. MATERIALS AND METHODS: Embryos at 24 and 72 h postfertilization were irradiated at the entrance plateau and the mid spread-out Bragg peak of a 150 MeV proton beam and with reference photons. Radiation-induced DNA double-strand breaks (DSB) and histopathological changes of the eye, muscles and brain were evaluated; deterioration of specific organs (eye, yolk sac, body) was measured. RESULTS: More and longer-lasting DSBs occurred in eye and muscle cells due to proton versus photon beams, albeit in different numbers. Edema, necrosis and tissue disorganization, (especially in the eye) were observed. Dose-dependent morphological deteriorations were detected at ≥10 Gy dose levels, with relative biological effectiveness between 0.99±0.07 (length) and 1.12±0.19 (eye). CONCLUSION: Quantitative assessment of radiation induced changes in zebrafish embryos proved to be beneficial for the radiobiological characterization of proton beams.

Protection of Lycopene against Embryonic Anomalies and Yolk Sac Placental Vasculogenic Disorders Induced by Nicotine Exposure.

Identification of a new agent from natural products for the protection of embryonic anomalies is potentially valuable. To investigate the protective effect exerted by lycopene against nicotine-induced malformations, mouse embryos in embryonic day 8.5 with yolk sac placentas were cocultured with 1 mM nicotine and/or lycopene (1 × 10-6, 1 × 10-5 µM) for 48 h. The morphological defects and apoptotic cell deaths in the embryo and yolk sac placenta of the nicotine group were significantly increased. Exposure to nicotine resulted in reduced superoxide dismutase (SOD) activity and cytoplasmic SOD and cytoplasmic glutathione peroxidase mRNA levels, but increased lipid peroxidation level in embryos. Moreover, treatment with nicotine resulted in aggravated expressions of the mRNA or protein level of antiapoptotic (BCL2-associated X protein, B-cell lymphoma-extralarge, and caspase 3), anti-inflammatory (nuclear factor kappa-light-chain-enhancer of activated B cells and tumor necrosis factor-alpha), and vasculogenic (vascular endothelial growth factor-alpha, insulin-like growth factor-1, alpha smooth muscle actin, transforming growth factor-beta 1, and hypoxia inducible factor-1 alpha) factors in the embryo and yolk sac placenta. However, all the parameters were significantly improved by treatment with lycopene, as compared to the nicotine group. These findings indicate the potential of lycopene as a protective agent against embryonic anomalies and yolk sac vasculogenic and placenta-forming defects induced by nicotine through modulations of oxidative, apoptotic, vasculogenic, and inflammatory activities.

Stavudine exposure results in developmental abnormalities by causing DNA damage, inhibiting cell proliferation and inducing apoptosis in mouse embryos.

Stavudine is an anti-AIDS drug widely used to prevent HIV transmission from pregnant mothers to the fetuses in underdeveloped countries for its low price. However, there is still a controversy on whether stavudine affects embryo development. In the current study, embryotoxicity of stavudine was evaluated using cultured mouse embryos with the concentrations: 5, 10, 15 µM and vehicle control. The data indicated that the effect of stavudine was dose-dependent at early neurogenesis. Stavudine exposure reduced somite numbers, yolk sac diameter, crown-rump length, and increased the rate of embryonic degeneration compared with the control. We chose the lowest but clearly toxic concentration: 5 µM to investigate the molecular mechanisms of the damage. At the molecular level, stavudine produced DNA damage, increased the levels of the phospho-CHK1 and cleaved-caspase-3, and decreased the expression level of proliferating cell nuclear antigen. These changes indicated that stavudine caused a coordinated DNA damage response, inhibited cell proliferation, and induced apoptosis in the embryos. Collectively these results suggest that stavudine exposure disturbs the embryonic development, and its use in pregnant mothers should be re-examined.

Heat shock protein 60 regulates yolk sac erythropoiesis in mice.

The yolk sac is the first site of blood-cell production during embryonic development in both murine and human. Heat shock proteins (HSPs), including HSP70 and HSP27, have been shown to play regulatory roles during erythropoiesis. However, it remains unknown whether HSP60, a molecular chaperone that resides mainly in mitochondria, could also regulate early erythropoiesis. In this study, we used Tie2-Cre to deactivate the Hspd1 gene in both hematopoietic and vascular endothelial cells, and found that Tie2-Cre+Hspd1f/f (HSP60CKO) mice were embryonic lethal between the embryonic day 10.5 (E10.5) and E11.5, exhibiting growth retardation, anemia, and vascular defects. Of these, anemia was observed first, independently of vascular and growth phenotypes. Reduced numbers of erythrocytes, as well as an increase in cell apoptosis, were found in the HSP60CKO yolk sac as early as E9.0, indicating that deletion of HSP60 led to abnormality in yolk sac erythropoiesis. Deletion of HSP60 was also able to reduce mitochondrial membrane potential and the expression of the voltage-dependent anion channel (VDAC) in yolk sac erythrocytes. Furthermore, cyclosporine A (CsA), which is a well-recognized modulator in regulating the opening of the mitochondrial permeability transition pore (mPTP) by interacting with Cyclophilin D (CypD), could significantly decrease cell apoptosis and partially restore VDAC expression in mutant yolk sac erythrocytes. Taken together, we demonstrated an essential role of HSP60 in regulating yolk sac cell survival partially via a mPTP-dependent mechanism.

Triptolide preserves glomerular barrier function via the inhibition of p53-mediated increase of GADD45B.

Podocytes are important to glomerular filtration barrier integrity and maintenance of size selectivity in protein filtration in the kidney. Although there is evidence to suggest that triptolide has direct protective effects on podocyte injuries, the mechanism mediating this process remains largely unexplored. In this study, we found triptolide suppresses podocyte p53 and GADD45B expression in vivo and in vitro. We used our previously developed in vivo zebrafish model of inducible podocyte-targeted injury and found that triptolide or the inhibition of p53 and gadd45ba with morpholino (MO) alleviated metronidazole (MTZ) induced edema in zebrafish, while the overexpression of gadd45ba in podocytes blocked the protective effect of triptolide and p53 MO on podocyte injury in zebrafish. Further study showed that p53 directly transactivated GADD45B. Triptolide inhibited p53 binding to the GADD45B promoter and subsequent GADD45B transcription. We further demonstrated that p53 may indirectly regulate GADD45B expression via NF-κB signaling. Taken together, our findings demonstrated that triptolide maintained glomerular barrier function via the inhibition of p53-NF-κB-GADD45B signaling, which provides a new understanding of the antiproteinuric effects of triptolide in glomerular diseases.

High Glucose Level Induces Cardiovascular Dysplasia During Early Embryo Development.

The incidence of gestational diabetes mellitus (GDM) has increased dramatically amongst multiethnic population. However, how gestational diabetes mellitus damages the developing embryo is still unknown. In this study, we used yolk sac membrane (YSM) model to investigate angiogenesis in the developing chick embryo. We determined that in the presence of high glucose, it retarded the growth and extension of the embryonic vascular plexus and it also reduced the density of the vasculature in yolk sac membrane model. Using the same strategy, we used the chorioallantoic membrane (CAM) as a model to investigate the influence of high glucose on the vasculature. We established that high glucose inhibited development of the blood vessel plexus and the blood vessels formed had a narrower diameter than control vessels. Concurrent with the abnormal angiogenesis, we also examined how it impacted cardiogenesis. We determined the myocardium in the right ventricle and left atrium were significantly thicker than the control and also there was a reduction in glycogen content in cardiomyocytes. The high glucose also induced excess reactive oxygen species (ROS) production in the cardiomyocytes. We postulated that it was the excess reactive oxygen species that damaged the cardiomyocytes resulting in cardiac hyperplasia.

Yolk sac size & shape as predictors of first trimester pregnancy outcome: A prospective observational study.

OBJECTIVE: To determine the value of yolk sac size and shape for prediction of pregnancy outcome in the first trimester. MATERIAL AND METHODS: 500 pregnant women between 6+0 and 9+6 weeks of gestation underwent transvaginal ultrasound and yolk sac diameter (YSD), gestational sac diameter (GSD) were measured, presence/absence of yolk sac (YS) and shape of the yolk sac were noted. Follow up ultrasound was done to confirm fetal well-being between 11+0 and 12+6 weeks and was the cutoff point of success of pregnancy. RESULTS: Out of 500 cases, 8 were lost to follow up, YS was absent in 14, of which 8 were anembryonic pregnancies. Thus, 478 out of 492 followed up cases were analyzed for YS shape and size and association with the pregnancy outcome. In our study, abnormal yolk sac shape had a sensitivity and specificity (87.06% & 86.5% respectively, positive predictive value (PPV) of 58.2%, negative predictive value (NPV) of 96.8% in predicting a poor pregnancy outcome as compared to yolk sac diameter (sensitivity and specificity 62.3% & 64.1% respectively and PPV and NPV of 27.3% and 88.7% respectively). The degree of association for both the variables was significant to the level of p<0.000. CONCLUSION: The presence or absence of yolk sac has a strong predictive value for poor pregnancy outcome. Yolk sac shape was a better predictor of poor pregnancy outcome in terms of higher specificity and negative predictive value as compared to yolk sac diameter.

Developmental toxicity and inhibition of the fungicide hymexazol to melanin biosynthesis in zebrafish embryos.

Hymexazol is an efficacious and widely used fungicide. However, its environmental toxicological assessment has not been well documented. It had no report of its toxicity to fish embryo. Fish embryo acute toxicity tests are highly predictive of aquatic embryotoxicity outcome. In this study, zebrafish (Danio rerio) embryos were exposed to hymexazol at varying concentrations for the study of the developmental toxicity, melanin biosynthesis, biochemical and transcriptional endpoints. The embryotoxicity tests indicated that the 96h LC50 value of hymexazol was 649mg/L with a 95% confidence interval range of 632-667mg/L. Hymexazol at concentrations of 417-738mg/L decreased the heart rate and increased the voluntary swing. Hymexazol inhibited normal development at concentrations above 554mg/L. the 96h EC50 was 411mg/L. Hymexazol in a concentration range of 417-738mg/L induced cardiac edema and yolk sac edema. Exposure of hymexazol at such concentrations to zebrafish embryos for 48h decreased the pigment area density compared with the no hymexazol control. Tyrosinase activity was inhibited by hymexazol relative to the untreated control. The P53 mRNA expression level in embryos upon exposure to 480mg/L or greater of hymexazol was significantly higher than that of the control. The results indicated that hymexazol has quite low acute toxicity and low embryotoxicity to zebrafish.

Yolk sac erythromyeloid progenitors expressing gain of function PTPN11 have functional features of JMML but are not sufficient to cause disease in mice.

BACKGROUND: Accumulating evidence suggests the origin of juvenile myelomonocytic leukemia (JMML) is closely associated with fetal development. Nevertheless, the contribution of embryonic progenitors to JMML pathogenesis remains unexplored. We hypothesized that expression of JMML-initiating PTPN11 mutations in HSC-independent yolk sac erythromyeloid progenitors (YS EMPs) would result in a mouse model of pediatric myeloproliferative neoplasm (MPN). RESULTS: E9.5 YS EMPs from VavCre+;PTPN11D61Y embryos demonstrated growth hypersensitivity to granulocyte-macrophage colony-stimulating factor (GM-CSF) and hyperactive RAS-ERK signaling. Mutant EMPs engrafted the spleens of neonatal recipients, but did not cause disease. To assess MPN development during unperturbed hematopoiesis we generated CSF1R-MCM+;PTPN11E76K ;ROSAYFP mice in which oncogene expression was restricted to EMPs. Yellow fluorescent protein-positive progeny of mutant EMPs persisted in tissues one year after birth and demonstrated hyperactive RAS-ERK signaling. Nevertheless, these mice had normal survival and did not demonstrate features of MPN. CONCLUSIONS: YS EMPs expressing mutant PTPN11 demonstrate functional and molecular features of JMML but do not cause disease following transplantation nor following unperturbed development. Developmental Dynamics 246:1001-1014, 2017. © 2017 Wiley Periodicals, Inc.