Integrative cross-species transcriptome analysis reveals earlier occurrence of myelopoiesis in pre-circulation primates compared to mice.

Hematopoiesis originates in the yolk sac, which forms prior to the establishment of blood circulation and exhibits distinct developmental processes between primates and mice. Despite increasing appreciation of yolk sac hematopoiesis for its lifelong contribution to the adult hematopoietic system and its regulatory roles in organogenesis, cross-species differences, particularly before the onset of blood circulation, remain incompletely understood. In this study, we constructed an integrative cross-species transcriptome atlas of pre-circulation hematopoiesis in humans, monkeys ( Macaca fascicularis), and mice. This analysis identified conserved populations between primates and mice, while also revealing more differentiated myeloid, erythroid, and megakaryocytic lineages in pre-circulation primates compared to mice. Specifically, SPP1-expressing macrophages were detected in primates before the onset of blood circulation but were absent in mice. Cell-cell communication analysis identified CSF1 + extraembryonic mesoderm cells as a potential supportive niche for macrophage generation, with ligand-receptor interactions between macrophages and other cell populations in the human yolk sac. Interestingly, pre-circulation SPP1 + macrophages exhibited hallmark signatures reminiscent of a macrophage subset that positively regulates hematopoietic stem cell generation. Our findings provide a valuable cross-species resource, advancing our understanding of human pre-circulation yolk sac hematopoiesis and offering a theoretical basis for the regeneration of functional blood cells.

Metastatic epidural spinal cord compression from testicular yolk sac tumor: case report and literature review.

Background: Yolk sac tumor (YST), or endodermal sinus tumor, is classically associated with pediatric populations. Metastasis to the spine rarely occurs, usually involving the lower thoracic or lumbar vertebrae. The objective of this report is to present a rare case of YST metastasis to the lower cervical and upper thoracic vertebrae in an adult male. A case-based review of the literature on metastatic YSTs was also performed as an update to the relevant literature. Case Description: A 28-year-old male with a history of YST presented to our institution with urinary retention, increasing weakness in the upper extremities, and acute onset lower extremity weakness. Computed tomography (CT) and magnetic resonance imaging (MRI) scans confirmed evidence of metastasis from a known YST with symptomatic cord compression. The patient was treated with surgical excision via decompressive laminectomies with instrumentation as described, and histopathologic analysis of the specimen confirmed YST metastasis. His disease recurred one year after index surgery. He succumbed to his disease despite repeated debulking. Conclusions: Metastasis of YST is rare, but metastasis to lower cervical and upper thoracic vertebrae is possible. YSTs are usually treated via primary surgical resection. Systemic chemotherapy and radiation may prevent recurrence. However, individualized treatment is imperative for improved patient outcomes.

Critical appraisal of the chorioallantoic membrane model for studying angiogenesis in preclinical research.

BACKGROUND: Angiogenesis, the biological mechanism by which new blood vessels are generated from existing ones, plays a vital role in growth and development. Effective preclinical screening is necessary for the development of medications that may enhance or inhibit angiogenesis in the setting of different disorders. Traditional in vitro and, in vivo models of angiogenesis are laborious and time-consuming, necessitating advanced infrastructure for embryo culture. MAIN BODY: A challenge encountered by researchers studying angiogenesis is the lack of appropriate techniques to evaluate the impact of regulators on the angiogenic response. An ideal test should possess reliability, technical simplicity, easy quantifiability, and, most importantly, physiological relevance. The CAM model, leveraging the extraembryonic membrane of the chicken embryo, offers a unique combination of accessibility, low cost, and rapid development, making it an attractive option for angiogenesis assays. This review evaluates the strengths and limitations of the CAM model in the context of its anatomical and physiological properties, and its relevance to human pathophysiological conditions. Its abundant capillary network makes it a common choice for studying angiogenesis. The CAM assay serves as a substitute for animal models and offers a natural setting for developing blood vessels and the many elements involved in the intricate interaction with the host. Despite its advantages, the CAM model's limitations are notable. These include species-specific responses that may not always extrapolate to humans and the ethical considerations of using avian embryos. We discuss methodological adaptations that can mitigate some of these limitations and propose future directions to enhance the translational relevance of this model. This review underscores the CAM model's valuable role in angiogenesis research and aims to guide researchers in optimizing its use for more predictive and robust preclinical studies. CONCLUSION: The highly vascularized chorioallantoic membrane (CAM) of fertilized chicken eggs is a cost-effective and easily available method for screening angiogenesis, in comparison to other animal models.

Primary yolk sac tumor of the endometrium combined with situs inversus totalis: a case report and literature review.

BACKGROUND: Yolk sac tumor (YST) is a highly malignant germ cell tumor, a majority of which originate from the gonads and are extremely rare from endometrium. CASE PRESENTATION: Here we present a case of a 42-year-old woman suffered from primary pure yolk sac tumor of the endometrium complicated with situs inversus totalis. The patient presented at our hospital with irregular vaginal bleeding. Imageological examination showed a space-occupying lesion in the cervix and the serum Alpha-fetoprotein (AFP) level was significantly high (more than 1210ng/ml). Then she underwent total hysterectomy, bilateral salpingo-oophorectomy and pelvic lymph node dissection. The subsequent postoperative pathological diagnosis was yolk sac tumor arising from the endometrium. Next, the patient was treated with 6 cycles of chemotherapy with Pingyangmycin, etoposide and cisplatin regimen and was alive without evidence of recurrence or distant metastases for 13 months. CONCLUSIONS: This rare disease needs to be differentiated from endometrial epithelial neoplasia and the significant increase in AFP is helpful for diagnosis. Combined with previous literature reports, comprehensive staging laparotomy or maximum cytoreductive surgery complemented by standard chemotherapy can usually achieve a good efficacy.

Giant ovarian yolk sac tumor during late pregnancy: a case report and literature review.

The manifestation of a giant ovarian yolk sac tumor during late pregnancy is relatively rare. A yolk sac tumor is a highly malignant germ cell tumor that originates from primitive germ cells. It is characterized by yolk sac differentiation in vitro. The frequency of prenatal examinations should be appropriately increased for ovarian tumors discovered during pregnancy. Furthermore, regular follow-up ultrasound should be performed, and tumor markers should be dynamically detected. If needed, imaging examinations such as computed tomography and magnetic resonance imaging should be combined to comprehensively investigate disease progression. If the tumor diameter and tumor marker levels rapidly increase during pregnancy, the possibility of malignancy increases. Therefore, exploratory laparotomy should be immediately performed to further improve subsequent treatment modalities, early diagnosis, early treatment, and prognosis. Herein, we report the case of a 28-year-old pregnant woman whose pregnancy was terminated at 29 weeks and 5 days. She complained of lower abdominal pain for 2 days. A pelvic mass was detected for 1 week, accompanied by increased levels of tumor markers such as serum alpha-fetoprotein, cancer antigen 125, carbohydrate antigen 724, and human epididymis protein 4. Imaging revealed the presence of a pelvic mass. At 32 weeks and 3 days of pregnancy, a cesarean section was performed, with a transverse incision in the lower uterine segment. Furthermore, pelvic adhesiolysis, omentectomy, right adnexectomy, right pelvic lymph node dissection, and pelvic metastasis peritonectomy were performed. The postoperative pathological diagnosis was yolk sac tumors of the ovary (stage IIB). Postoperatively, a five-cycle chemotherapy regimen comprising bleomycin, etoposide, and cisplatin was administered. During postoperative follow-up, the patient's general condition was noted to be good, with the newborn and pregnant women ultimately achieving good outcomes. We reviewed the relevant literature to increase clinical doctors' understanding of ovarian malignancy during pregnancy, guide treatment selection, and facilitate early intervention for associated diseases.

Subtle Presentation of Two Rare Gynecological Cancers in a Single Patient: A Case Report.

Yolk sac tumors (YSTs) are rare germ-cell malignancies that usually develop in the gonads. Similarly, gastric-type adenocarcinoma of the endocervix (GAS) is a rare kind of gynecological cancer that has piqued interest due to its distinctive clinical and pathological features. These two malignancies in a single patient present a unique and challenging scenario. Here, we present the case of a 33-year-old female who presented with postcoital bleeding and was diagnosed with atypical glandular proliferation consistent with GAS. Interestingly, this patient had a history of a YST treated with left salpingo-oophorectomy and chemoradiation in the Philippines five years prior. A follow-up ultrasound report in the Philippines five months after treatment showed no evidence of residual disease. This case report aims to understand the predisposing factors of these neoplasms and asks if there is a link between them, which is necessary for tailoring surveillance, appropriate therapeutic approaches, and improving patient outcomes.

Genetic Insights Into Early Pregnancy Loss: A Case Study of Trisomy 22 and an Enlarged Yolk Sac.

The first trimester of pregnancy is crucial for organ development but also carries a high risk of complications, with early pregnancy loss being the most common. Anomalies in the yolk sac, the first extra-embryonic structure seen by ultrasonography, can indicate severe fetal growth abnormalities and are linked to higher rates of first-trimester loss. This case report details a 38-year-old woman with a history of recurrent pregnancy loss (RPL) who presented with per vaginal bleeding and mild abdominal pain. Transvaginal ultrasonography revealed a yolk sac larger than 10 mm, prompting further genetic investigation. Chromosomal microarray analysis confirmed Trisomy 22. The presence of an enlarged yolk sac, correlated with Trisomy 22, highlights the importance of early detection through sonography and genetic testing. This approach aids in managing RPL by identifying genetic causes, thereby informing pre-conception counseling and future pregnancy management. An abnormal yolk sac size necessitates thorough evaluation, including cytogenetic microarray testing and quantitative fluorescent-polymerase chain reaction analysis, to guide clinical decisions and improve pregnancy outcomes.

Yolk sac tumor of the liver in an infant: A case report.

Yolk sac tumors can occur in various extragonadal sites, including the hepatobiliary tract, and are often associated with elevated serum alpha-fetoprotein. We report the case of a 14-month-old male infant presenting with abdominal pain and distension. Ultrasound and computed tomography scans of the abdomen revealed contiguous hepatic masses with lobulated contours, containing areas of necrosis. The patient underwent surgical resection, and histological studies confirmed the diagnosis of a yolk sac tumor. The occurrence of a yolk sac tumor in the liver is extremely rare. Ultrasound and cross-sectional imaging can be highly effective in diagnosing these tumors when combined with biopsy procedures to confirm the diagnosis. Although rare, yolk sac tumors of the liver should be considered a differential diagnosis for hepatic masses.

Characterization of testicular embryonic-type neuroectodermal tumor and embryonic-type neuroectodermal tissue admixed with mature neuro-glial tissue using a broad immunohistochemical panel.

Embryonic-type neuroectodermal tumor (ENT) is a somatic-type malignancy characterized by overgrowth of embryonic-type neuroectodermal tissue (EtNT). In germ cell tumors, EtNT is frequently intermingled with other components that may exhibit significant morphologic overlap [mature neuro-glial tissue (MNGT), nephroblastomatous tissues, and primitive endodermal-type glands]. Therefore, the quantification of EtNT (crucial for the diagnosis of ENT) can be challenging. In this study, we investigated the immunohistochemical profile of ENT, EtNT, and MNGT using a broad immunohistochemical panel. We found that SOX2 was the most sensitive marker for EtNT (100%), but it also stained MNGT (28.6%). GFAP and S100 were relatively sensitive (71.4%) and highly specific (GFAP 100%, S100 85.8%) for MNGT, whereas synaptophysin stained both. Combining our results with those of previous studies, we propose that a combination of SOX11, SOX2, GFAP, S100, AFP, villin, CDX2, PAX8, and nuclear WT1 may help to identify and quantify EtNT in germ cell tumors.

Case report: Ovarian steroid cell tumor with CA72-4 elevated.

Ovarian steroid cell tumor, not otherwise specified (SCT-NOS), is a rare subtype of sex cord-stromal tumor, characterized by hirsutism and virilization. There are, however, few tumor markers reported in the tumor. The following is a case report. Six years ago, the patient underwent a left adnexectomy after being diagnosed with a yolk sac tumor. Her serum CA72-4 levels were significantly elevated when she was diagnosed with SCT-NOS. She suffered from hirsutism and oligomenorrhea with long menstrual cycles. SCT-NOS was confirmed by her histopathological examination. When the tumor was diagnosed, serum CA72-4 levels were elevated. Following tumor resection, serum CA72-4 levels returned to the average reference interval. Whole-exome sequencing (WES) was utilized to identify ten mutations in MKI67, TICAM1, CHD3, ARID5B, ERBB4, POLD1, FZR1, MTCP1, TBX3, and CLTC genes.

Human liver sinusoidal endothelial cells support the development of functional human pluripotent stem cell-derived Kupffer cells.

In mice, the first liver-resident macrophages, known as Kupffer cells (KCs), are thought to derive from yolk sac (YS) hematopoietic progenitors that are specified prior to the emergence of the hematopoietic stem cell (HSC). To investigate human KC development, we recapitulated YS-like hematopoiesis from human pluripotent stem cells (hPSCs) and transplanted derivative macrophage progenitors into NSG mice previously humanized with hPSC-liver sinusoidal endothelial cells (LSECs). We demonstrate that hPSC-LSECs facilitate stable hPSC-YS-macrophage engraftment for at least 7 weeks. Single-cell RNA sequencing (scRNA-seq) of engrafted YS-macrophages revealed a homogeneous MARCO-expressing KC gene signature and low expression of monocyte-like macrophage genes. In contrast, human cord blood (CB)-derived macrophage progenitors generated grafts that contain multiple hematopoietic lineages in addition to KCs. Functional analyses showed that the engrafted KCs actively perform phagocytosis and erythrophagocytosis in vivo. Taken together, these findings demonstrate that it is possible to generate human KCs from hPSC-derived, YS-like progenitors.

Mimicking Metastasis: Endobronchial Tuberculosis Presenting as a Mass in a Pediatric Patient With Yolk Sac Tumor.

Before the advent of an effective antitubercular treatment for tuberculosis and bronchoscopy, endobronchial tuberculosis (EBTB) often greatly contributed to airway stenosis and lung atelectasis in children. Even after the advent of efficacious therapy, EBTB poses major challenges for pediatric patients, manifesting as airway stenosis or obstruction. We report a case of a two-year-old male with a previous history of yolk sac testicular tumor whose follow-up PET-CT scan showed right middle lobe collapse. Flexible bronchoscopy demonstrated endobronchial mass, and biopsy revealed EBTB, excluding metastasis. This case illustrates varied presentations of tuberculosis and highlights the significance of early diagnosis with bronchoscopy in treating this condition before it can lead to severe complications. Antitubercular therapy must be initiated at the earliest when managing EBTB. The follow-up procedures must be diligent, and timely interventions should be made for optimal patient outcomes despite the availability of improved diagnostic techniques and treatment methods.

Subxiphoid robot-assisted complete resection for postchemotherapy primary mediastinal yolk sac tumour.

The standard treatment for primary mediastinal yolk sac tumour involves neoadjuvant chemotherapy followed by residual tumour resection, typically performed through a median sternotomy or a thoracotomy. However, in this case, a 16-year-old patient with a large anterior mediastinal tumour underwent less invasive, subxiphoid, robot-assisted surgery using a 4-arm da Vinci Xi system with CO2 insufflation at 8 mmHg. The tumour, located in the right thymic lobe, was dissected using a technique similar to blunt dissection, bipolar electrocautery and vessel sealer. Pericardiotomy was performed suspecting tumour invasion, with the thickened pericardial border incised circularly from the left side. Preservation of the right phrenic nerve involved careful separation from the densely adherent tumour. A pulmonary wedge resection was also performed using a stapler. The pericardial defect was reconstructed using an expanded polytetrafluoroethylene sheet, sutured together with nylon threads, and the resected tumour was extracted with a retrieval bag. This subxiphoid robot-assisted approach is a minimally invasive option for malignant mediastinal tumours.

Genomics, the diversification of mammals, and the evolution of placentation.

When and why did variations in placental structure and function evolve? Such questions cannot be addressed without a reliable version of mammalian phylogeny. Twenty-five years ago, the mammalian tree was reshaped by molecular phylogenetics. Soon it was shown, in contrast to prevailing theories, that the common ancestor of placental mammals had invasive placentation. Subsequently, evolution of many other features of extraembryonic membranes was addressed. This endeavour stimulated research to fill gaps in our knowledge of placental morphology. Last year the mammalian tree was again revised based on a large set of genomic data. With that in mind, this review provides an update on placentation in the nineteen orders of placental mammals, incorporating much recent data. The principal features such as shape, interdigitation, the interhaemal barrier and the yolk sac are summarized in synoptic tables. The evolution of placental traits and its timing is then explored by reference to the revised mammalian tree. Examples are the early appearance of epitheliochorial placentation in the common ancestor of artiodactyls, perissodactyls, pangolins and carnivores (with reversion to invasive forms in the latter) and later refinements such as the binucleate trophoblast cells and placentomes of ruminants. In primates, the intervillous space gradually evolved from the more basic labyrinth whereas trophoblast invasion of the decidua was a late development in humans and great apes. Only seldom can we glimpse the "why" of placental evolution. The best examples concern placental hormones, including some striking examples of convergent evolution such as the chorionic gonadotropins of primates and equids. In concluding, I review current ideas about what drives placental evolution and identify significant gaps in our knowledge of placentation, including several relevant to the evolution of placentation in primates.

Human yolk sac-derived innate lymphoid-biased multipotent progenitors emerge prior to hematopoietic stem cell formation.

Hematopoietic stem cell (HSC)-independent lymphopoiesis has been elucidated in murine embryos. However, our understanding regarding human embryonic counterparts remains limited. Here, we demonstrated the presence of human yolk sac-derived lymphoid-biased progenitors (YSLPs) expressing CD34, IL7R, LTB, and IRF8 at Carnegie stage 10, much earlier than the first HSC emergence. The number and lymphopoietic potential of these progenitors were both significantly higher in the yolk sac than the embryo proper at this early stage. Importantly, single-cell/bulk culture and CITE-seq have elucidated the tendency of YSLP to differentiate into innate lymphoid cells and dendritic cells. Notably, lymphoid progenitors in fetal liver before and after HSC seeding displayed distinct transcriptional features, with the former closely resembling those of YSLPs. Overall, our data identified the origin, potential, and migratory dynamics of innate lymphoid-biased multipotent progenitors in human yolk sac before HSC emergence, providing insights for understanding the stepwise establishment of innate immune system in humans.

Impact of microscopic deposits of yolk sac tumor on recurrence of mature sacrococcygeal teratoma.

INTRODUCTION: Sacrococcygeal teratomas (SCT) with malignant histology frequently recur and are treated aggressively, but risk factors and surveillance protocols are less established for mature tumors. In particular, prior studies have not investigated whether microscopic deposits of yolk sac tumor (YST) in otherwise mature teratomas lead to higher recurrence rates. METHODS: We reviewed patients with mature SCTs resected at our institution from 2011 to 2021 and analyzed tumor characteristics, treatment, and outcomes. RESULTS: We identified 56 patients with mature SCT, of which 9 (16%) demonstrated microscopic YST. Following surgery, 7/56 (13%) patients developed local recurrence at a mean of 1.2 ± 0.7 years, while no patients developed metastases. Recurrence was more likely in patients with microscopic YST [5/9 (56%) vs. 2/47 (4%), p = 0.021] and positive margins [6/24 (35%) vs. 1/32 (3.1%), p = 0.030]. A solid tumor component tended to increase recurrence risk as well [6/29 (21%) vs. 1/27 (4%), p = 0.053]. Five patients demonstrated malignant recurrence and were all detected by a rising alpha-fetoprotein (AFP), while two patients demonstrated recurrence of mature teratoma and were detected on surveillance magnetic resonance imaging (MRI). CONCLUSIONS: Microscopic foci of YST may increase recurrence risk for patients with mature SCT. Such patients might benefit from closer postoperative surveillance with serial AFP measurements and MRI.

Half-life of serum alpha-fetoprotein in prepubertal testicular yolk sac tumors: an index significantly associated with prognosis.

PURPOSE: To evaluate the association between serum alpha-fetoprotein (AFP) half-life (HL) and prognosis in prepubertal children with elevated AFP values 3 to 4 weeks after surgery for testicular yolk sac tumors (YST). METHODS: Prepubertal patients with testicular YST treated with radical orchiectomy between January 2016 and December 2022 were retrospectively reviewed. Negative outcomes were defined as relapse, metastasis or death. Univariate and multivariate logistic regression analyses were conducted to select risk factors for negative outcomes. RESULTS: A total of 42 patients were eventually enrolled into the study. Patients were divided into non-negative and negative outcomes groups, consisting of 35 and 7 patients, respectively. Thirty-five patients were stage I, two cases were stage II, and five cases were stage IV, according to the Children's Oncology Group staging system. The overall survival (OS) rate was 100%. Average AFP values significantly decreased after resection (P < 0.001). A significant positive correlation was shown between pre- and postoperative AFP values (r = 0.60, P < 0.001). Long AFP HL was considered as an independent risk factor for negative outcomes in YST patients underwent radical orchiectomy (P = 0.04). The cut-off value for AFP HL was 5.78 days, regardless of age division. CONCLUSION: Testicular YST is a relatively rare disease in children with an OS of 100%, and salvage chemotherapy is effective even in grade IV patients. The postoperative AFP HL was significantly associated with prognosis in prepubertal patients with testicular YST. The cut-off value for AFP HL is 5.78 days regardless of the effect of physiological AFP elevation.

Ultrasonographic and clinicopathological features of pelvic yolk sac tumors in women: a single-center retrospective analysis.

Objectives: Yolk sac tumors (YSTs) are rare and highly malignant ovarian malignancies that have a very poor prognosis. The aim of this study is to delineate the ultrasound and clinicopathological features of female pelvic YSTs to better understand the disease. Methods: This study was a retrospective analysis of the clinicopathological and ultrasound imaging data from 16 YST patients who received treatment at our hospital between January 2012 and August 2023. Then, the ultrasound imaging characteristics were compared with pathological findings. Results: Among the 16 patients, various degrees of serum AFP increase were observed, and CA125 levels increased in 58.33% (7 out of 12) of patients. Thirteen patients (81.25%) had tumors located in ovary, two patients (12.5%) had tumors located in the sacrococcygeal region, and one patient (6.25%) had tumors located in the mesentery. Pathologically, nine patients presented with simple yolk sac tumors and seven with mixed germ cell tumors. According to the ultrasound manifestations, YST lesions can be classified into three types. (1) the cystic type, was diagnosed in two patients who presented with a large cystic mass with regular morphology and clear boundary and dense liquid within the cyst; and (2) the cystic-solid mixed type, was diagnosed in 4 patients. On 2D ultrasound, the lesions showed a cystic-solid mixed echo, and color Doppler showed a rich blood flow signal in the solid region and cystic separation. made up of four cases. (3) In ten patients with the solid type, 2D ultrasound showed solid uniform echoes with clear boundaries. The "fissure sign" was observed in the lesion. Color Doppler displayed rich blood flow in the solid part, and PW showed low to moderate resistance index of artery (RI:0.21-0.63). On contrast-enhanced ultrasound (CEUS), rapid and high enhancement in the solid part and cystic separation was observed in 2 patients. Conclusions: Combining ultrasound features with clinical information and tumor markers provides reliable clues for the diagnosis of YST. The application of two-dimensional ultrasound and CEUS combined with patient tumor marker levels can provide a robust reference for determining the necessity of fertility-preserving surgery and postoperative chemotherapy, which can improve clinical decision-making and patient consultation.