Ewing family of tumors is a group of highly aggressive neoplasias that occur most commonly in the first two decades of life. These tumors are most frequently localized in bones, less frequently in soft tissues. They usually appear as undifferentiated small round-cell tumors. With current treatment regiments, 5-year disease-free survival rates exceed 60% in patients with a localized disease. Patients with metastatic disease at the time of their first presentation have a poor prognosis. We describe a rare case of visceral primitive neuroectodermal tumor with the involvement of the kidney in a 9-year-old girl. The tumor was studied with immunohistochemistry, cytogenetics, and molecular biology methods. Strong expression of protein MIC(2) by immunochemistry (antibody HBA 71) with subsequent demonstration of a translocation consistent with t(11;22)(q24;q12) using cytogenetic and reverse transcriptase polymerase chain reaction (RT-PCR) confirmed the histopathological diagnosis of peripheral primitive neuroectodermal tumor. We detected minimal residual disease in bone marrow using RT-PCR.
- MeSH
- Bone Marrow Cells pathology MeSH
- Child MeSH
- Karyotyping MeSH
- Humans MeSH
- RNA, Messenger genetics MeSH
- Kidney Neoplasms genetics pathology MeSH
- Reverse Transcriptase Polymerase Chain Reaction MeSH
- Neuroectodermal Tumors, Primitive genetics pathology MeSH
- Chromosome Banding MeSH
- Recombinant Fusion Proteins genetics MeSH
- Check Tag
- Child MeSH
- Humans MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Case Reports MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- RNA, Messenger MeSH
- Recombinant Fusion Proteins MeSH
In 1918, Stout defined the lesion in which small round cells originating from the ulnar nerve formed a rosette as neuroepithelioma. It was claimed that this tumor originated from neuroectodermis and was different from the classical neuroblastoma. The term primitive neuroectodermal tumor (PNET) involves a group of tumors of the soft tissue originating from neural crest and resulting from the brain, spinal cord and branches of the sympathetic nervous system. Extracranial primitive neuroectodermal tumors originate from neural crest cells outside the sympathetic and central nervous system. PNET also has some distinctive histological, immunohistochemical and ultrastructural features. It is usually encountered in children and young adults; most frequently located in thoracopulmonary region (Askin's tumor). The second most commonly involved body part is the extremities. It is very rarely located on the face. PNET is an aggressive tumor. In fact, the disease has a rapid progression, causes local or distant metastases and 50% of the patients die within two years of the presentation. It is treated with aggressive surgery as well as chemotherapy and radiotherapy. In this report, we presented a case of PNET located on the right cheek with multiple distant metastases. Clinicians should be on alert when treating facial tumors, not to skip PNET, which is a very aggressive one.
- MeSH
- Humans MeSH
- Bone Neoplasms secondary MeSH
- Facial Neoplasms pathology surgery MeSH
- Lung Neoplasms secondary MeSH
- Neuroectodermal Tumors pathology surgery MeSH
- Aged MeSH
- Cheek MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Aged MeSH
- Publication type
- Journal Article MeSH
- Case Reports MeSH
We report four cases of uterine tumors with neuroectodermal differentiation. One tumor had neuroectodermal component only; in the three other tumors, the neuroectodermal component was admixed with another component, namely rhabdomyosarcoma (1 case), and endometrioid adenocarcinoma (2 cases). Histologically, the neuroectodermal component consisted of small to medium sized cells arranged in diffuse sheets. The tumor cells had round nuclei with stippled to coarsely granular chromatin, mostly with non-prominent nucleoli, and scant eosinophilic or amphophilic cytoplasm. Immunohistochemically, 4/4 tumors showed expression of vimentin, synaptophysin and CD56; 3/4 tumors were CD99 and NSE positive; 2/4 tumors showed focal expression of S-100 protein; and 1/4 tumors had focal dot-like cytoplasmic positivity for cytokeratin AE1/AE3. FLI-1 was negative in all cases. FISH examination was performed and none of the tumors showed rearrangement of EWSR1 gene. Uterine tumors with neuroectodermal differentiation are rare; to the best of our knowledge only 44 cases have been reported in the literature to date, referred to as Ewing sarcoma, peripheral PNET (pPNET), PNET (not otherwise specified) and uterine tumors with neuroendocrine differentiation.
- MeSH
- Cell Differentiation physiology MeSH
- Gene Rearrangement MeSH
- Immunohistochemistry MeSH
- Middle Aged MeSH
- Humans MeSH
- Uterine Neoplasms genetics pathology MeSH
- Neuroectodermal Tumors genetics pathology MeSH
- RNA-Binding Protein EWS MeSH
- Calmodulin-Binding Proteins genetics MeSH
- RNA-Binding Proteins genetics MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Aged, 80 and over MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Case Reports MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- EWSR1 protein, human MeSH Browser
- RNA-Binding Protein EWS MeSH
- Calmodulin-Binding Proteins MeSH
- RNA-Binding Proteins MeSH
GFP labeled/NE-4C neural progenitor cells cloned from primary neuroectodermal cultures of p53- mouse embryos give rise to neurons when exposed to retinoic acid in vitro. To study their survival and differentiation in vivo, cells were transplanted into the cortex of 6-week-old rats, 1 week after the induction of a photochemical lesion or into noninjured cortex. The electrophysiological properties of GFP/NE-4C cells were studied in vitro (8-10 days after differentiation induction) and 4 weeks after transplantation using the whole-cell patch-clamp technique, and immunohistochemical analyses were carried out. After transplantation into a photochemical lesion, a large number of cells survived, some of which expressed the astrocytic marker GFAP. GFP/GFAP-positive cells, with an average resting membrane potential (Vrest) of -71.9 mV, displayed passive time- and voltage-independent K+ currents and, additionally, voltage-dependent A-type K+ currents (KA) and/or delayed outwardly rectifying K+ currents (KDR). Numerous GFP-positive cells expressed NeuN, betaIII-tubulin, or 68 kD neurofilaments. GFP/betaIII-tubulin-positive cells, with an average Vrest of -61.6 mV, were characterized by the expression of KA and KDR currents and tetrodotoxin-sensitive Na+ currents. GFP/NE-4C cells also gave rise to oligodendrocytes, based on the detection of oligodendrocyte-specific markers. Our results indicate that GFP/NE-4C neural progenitors transplanted into the site of a photochemical lesion give rise to neurons and astrocytes with membrane properties comparable to those transplanted into noninjured cortex. Therefore, GFP/NE-4C cells provide a suitable model for studying neuro- and gliogenesis in vivo. Further, our results suggest that embryonic neuroectodermal progenitor cells may hold considerable promise for the repair of ischemic brain lesions.
- MeSH
- Astrocytes physiology MeSH
- Cell Differentiation drug effects MeSH
- Cell Line MeSH
- Denervation methods MeSH
- Ectoderm cytology MeSH
- Photosensitizing Agents MeSH
- Immunohistochemistry MeSH
- Brain Ischemia pathology therapy MeSH
- Stem Cells cytology physiology MeSH
- Membrane Potentials MeSH
- Patch-Clamp Techniques MeSH
- Disease Models, Animal MeSH
- Cerebral Cortex pathology physiology surgery MeSH
- Mice MeSH
- Neurons cytology physiology MeSH
- Oligodendroglia physiology MeSH
- Graft Survival MeSH
- Antineoplastic Agents pharmacology MeSH
- Stem Cell Transplantation * MeSH
- Tretinoin pharmacology MeSH
- Green Fluorescent Proteins genetics MeSH
- Animals MeSH
- Check Tag
- Mice MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Photosensitizing Agents MeSH
- Antineoplastic Agents MeSH
- Tretinoin MeSH
- Green Fluorescent Proteins MeSH
A primitive neuroectodermal tumour (PNET) of the minor pelvis is a rare malignant small-cell tumour developing from the neural groove. It metastatizes into the lungs, bones, liver and brain. Treatment involves radical surgical extirpation followed by chemotherapy and actinotherapy. The author presents the case-history of PNET of the pelvis minor in a 33-year-old woman.
HMGB1 and HMGB2 proteins have been implicated in numerous cellular processes, including proliferation, differentiation, apoptosis, and tumor growth. It is unknown whether they are involved in regulating the typical functions of pluripotent human embryonic stem cells (hESCs) and/or those of the differentiated derivatives of hESCs. Using inducible, stably transfected hESCs capable of shRNA-mediated knockdown of HMGB1 and HMGB2, we provide evidence that downregulation of HMGB1 and/or HMGB2 in undifferentiated hESCs does not affect the stemness of cells and induces only minor changes to the proliferation rate, cell-cycle profile, and apoptosis. After differentiation is induced, however, the downregulation of those proteins has important effects on proliferation, apoptosis, telomerase activity, and the efficiency of differentiation toward the neuroectodermal lineage. Furthermore, those processes are affected only when one, but not both, of the two proteins is downregulated; the knockdown of both HMGB1 and HMGB2 results in a normal phenotype. Those results advance our knowledge of regulation of hESC and human neuroectodermal cell differentiation and illustrate the distinct roles of HMGB1 and HMGB2 during early human development.
- Keywords
- HMGB1, HMGB2, differentiation, human embryonic stem cells, neuroectodermal cells,
- MeSH
- Apoptosis genetics MeSH
- Cell Differentiation * MeSH
- Cell Self Renewal genetics MeSH
- Cell Line MeSH
- Cell Cycle genetics MeSH
- Cell Lineage genetics MeSH
- Down-Regulation genetics MeSH
- Histones metabolism MeSH
- Humans MeSH
- Human Embryonic Stem Cells cytology metabolism MeSH
- Neural Plate cytology MeSH
- Cell Proliferation genetics MeSH
- HMGB1 Protein metabolism MeSH
- HMGB2 Protein metabolism MeSH
- Telomerase metabolism MeSH
- Transfection MeSH
- Cell Shape genetics MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Histones MeSH
- HMGB1 Protein MeSH
- HMGB2 Protein MeSH
- Telomerase MeSH
- MeSH
- Cell Division MeSH
- Cell Line MeSH
- Dipeptidyl Peptidase 4 genetics metabolism MeSH
- Ectoderm enzymology MeSH
- Protease Inhibitors pharmacology MeSH
- Kinetics MeSH
- Humans MeSH
- RNA, Messenger genetics MeSH
- Reverse Transcriptase Polymerase Chain Reaction MeSH
- Cell Line, Transformed MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Dipeptidyl Peptidase 4 MeSH
- Protease Inhibitors MeSH
- RNA, Messenger MeSH
High-mobility group box (HMGB)1 and HMGB2 proteins are the subject of intensive research because of their involvement in DNA replication, repair, transcription, differentiation, proliferation, cell signaling, inflammation, and tumor migration. Using inducible, stably transfected human embryonic stem cells (hESCs) capable of the short hairpin RNA-mediated knockdown (KD) of HMGB1 and HMGB2, we provide evidence that deregulation of HMGB1 or HMGB2 expression in hESCs and their differentiated derivatives (neuroectodermal cells) results in distinct modulation of telomere homeostasis. Whereas HMGB1 enhances telomerase activity, HMGB2 acts as a negative regulator of telomerase activity in the cell. Stimulation of telomerase activity in the HMGB2-deficient cells may be related to activation of the PI3K/protein kinase B/ glycogen synthase kinase-3β/β-catenin signaling pathways by HMGB1, augmented TERT/telomerase RNA subunit transcription, and possibly also because of changes in telomeric repeat-containing RNA (TERRA) and TERRA-polyA+ transcription. The impact of HMGB1/2 KD on telomerase transcriptional regulation observed in neuroectodermal cells is partially masked in hESCs by their pluripotent state. Our findings on differential roles of HMGB1 and HMGB2 proteins in regulation of telomerase activity may suggest another possible outcome of HMGB1 targeting in cells, which is currently a promising approach aiming at increasing the anticancer activity of cytotoxic agents.-Kučírek, M., Bagherpoor, A. J., Jaroš, J., Hampl, A., Štros, M. HMGB2 is a negative regulator of telomerase activity in human embryonic stem and progenitor cells.
- Keywords
- HMGB1, hESCs, neuroectodermal cells, telomeres,
- MeSH
- Cell Differentiation MeSH
- Transcription, Genetic MeSH
- Stem Cells cytology enzymology MeSH
- Humans MeSH
- Human Embryonic Stem Cells cytology enzymology MeSH
- HMGB1 Protein genetics MeSH
- HMGB2 Protein genetics physiology MeSH
- Telomerase metabolism MeSH
- Transfection MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- HMGB1 protein, human MeSH Browser
- HMGB1 Protein MeSH
- HMGB2 Protein MeSH
- Telomerase MeSH
Neuroendocrine differentiation of lung tumours is characterised by the expression of several neuroendocrine markers and is confined mostly to specific histological subtypes, i.e. small cell carcinomas and carcinoids. One of the markers seen in neuroendocrine tumours, high activity of the aromatic L-amino acid decarboxylase (AADC), is helpful in distinguishing the classic and variant small cell lung tumour subtypes. Here, we have analysed the expression and quantified the level of mRNA coding for AADC in human tumour cell lines by use of the reverse transcription and polymerase chain reaction (RT-PCR). High amounts of mRNA were detected in classic small cell lung carcinomas and a neuroblastoma cell line. Other cell lines (melanomas, non-small cell lung carcinomas and osteosarcoma) also showed AADC expression, but the levels were 2-3 orders lower. Also, the tissue-specific (neuronal versus liver-specific) mRNA type has been estimated. Small cell lung carcinomas, neuroblastoma and melanoma expressed messenger RNA specific for neuronal tissues. Importantly, the non-small cell lung carcinoma cell lines expressed either liver-specific (non-neuronal) mRNA (cell line A549) or predominantly the neuronal (cell line NCI-H520) AADC message. These data indicate that a range of tumour cell lines transcribe the AADC gene and that two distinct types of AADC mRNA which reflect the embryonal (neuronal or non-neuronal) origin of the tumour may be produced in non-small cell lung cancer cells.
- MeSH
- Adenocarcinoma metabolism MeSH
- Aromatic-L-Amino-Acid Decarboxylases metabolism MeSH
- Humans MeSH
- Carcinoma, Small Cell metabolism MeSH
- Melanoma metabolism MeSH
- RNA, Messenger metabolism MeSH
- Tumor Cells, Cultured MeSH
- Neoplasm Proteins metabolism MeSH
- Lung Neoplasms metabolism MeSH
- Carcinoma, Non-Small-Cell Lung metabolism MeSH
- Neuroblastoma metabolism MeSH
- Neuroectodermal Tumors metabolism MeSH
- Neuroendocrine Tumors metabolism MeSH
- Polymerase Chain Reaction MeSH
- RNA Splicing MeSH
- Blotting, Southern MeSH
- Carcinoma, Squamous Cell metabolism MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Aromatic-L-Amino-Acid Decarboxylases MeSH
- RNA, Messenger MeSH
- Neoplasm Proteins MeSH
HMGB1 and HMGB2 proteins are abundantly expressed in human embryonic stem cells (hESCs) and hESC-derived progenitor cells (neuroectodermal cells, hNECs), though their functional roles in pluripotency and the mechanisms underlying their differentiation in response to the anticancer drug etoposide remain to be elucidated. Here, we show that HMGB1 and/or HMGB2 knockdown (KD) by shRNA in hESCs did not affect the cell stemness/pluripotency regardless of etoposide treatments, while in hESC-derived neuroectodermal cells, treatment resulted in differential effects on cell survival and the generation of rosette structures. The objective of this work was to determine whether HMGB1/2 proteins could modulate the sensitivity of hESCs and hESC-derived progenitor cells (hNECs) to etoposide. We observed that HMGB1 KD knockdown (KD) and, to a lesser extent, HMGB2 KD enhanced the sensitivity of hESCs to etoposide. Enhanced accumulation of 53BP1 on telomeres was detected by confocal microscopy in both untreated and etoposide-treated HMGB1 KD hESCs and hNECs, indicating that the loss of HMGB1 could destabilize telomeres. On the other hand, decreased accumulation of 53BP1 on telomeres in etoposide-treated HMGB2 KD hESCs (but not in HMGB2 KD hNECs) suggested that the loss of HMGB2 promoted the stability of telomeres. Etoposide treatment of hESCs resulted in a significant enhancement of telomerase activity, with the highest increase observed in the HMGB2 KD cells. Interestingly, no changes in telomerase activity were found in etoposide-treated control hNECs, but HMGB2 KD (unlike HMGB1 KD) markedly decreased telomerase activity in these cells. Changes in telomerase activity in the etoposide-treated HMGB2 KD hESCs or hNECs coincided with the appearance of DNA damage markers and could already be observed before the onset of apoptosis. Collectively, we have demonstrated that HMGB1 or HMGB2 differentially modulate the impact of etoposide treatment on human embryonic stem cells and their progenitor cells, suggesting possible strategies for the enhancement of the efficacy of this anticancer drug.
- Keywords
- HMGB1 and HMGB2, apoptosis, etoposide, human embryonic stem cells, neuroectodermal cells, telomerase,
- MeSH
- Apoptosis drug effects MeSH
- Cell Differentiation genetics MeSH
- Etoposide pharmacology MeSH
- Stem Cells drug effects MeSH
- Humans MeSH
- Human Embryonic Stem Cells MeSH
- RNA, Small Interfering MeSH
- Neoplastic Stem Cells drug effects metabolism MeSH
- Neoplasms drug therapy genetics pathology MeSH
- HMGB1 Protein antagonists & inhibitors genetics MeSH
- HMGB2 Protein antagonists & inhibitors genetics MeSH
- Antineoplastic Agents pharmacology MeSH
- Gene Expression Regulation, Neoplastic genetics MeSH
- Telomerase genetics MeSH
- Check Tag
- Humans MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Names of Substances
- Etoposide MeSH
- HMGB1 protein, human MeSH Browser
- RNA, Small Interfering MeSH
- HMGB1 Protein MeSH
- HMGB2 Protein MeSH
- Antineoplastic Agents MeSH
- Telomerase MeSH
