Marian Sulik

PLAGL1 protein is differentially expressed in the nephron segments and collecting ducts in human kidney

INTRODUCTION PLAGL1 (pleiomorphic adenoma gene-like 1) is a C2H2-type zinc finger transcription factor associated with the regulation of cell growth and development. Although PLAGL1 expression in kidney was assessed by biochemical methods, the exact localization of the PLAGL1 protein in human kidney has not yet been described. MATERIAL AND METHODS Macroscopically unchanged specimens of kidney tissue were collected from 39 patients undergoing nephrectomy due to renal cell carcinoma. H & E staining of paraffin sections was used to assess histology of the kidney whereas immunohistochemistry was used to localize PLAGL1 protein in kidney compartments. In addition, database sequences search for putative PLAGL1 binding sites among the kidney-related genes was performed. RESULTS PLAGL1 staining intensity differed depending on the kidney compartment. Strong PLAGL1 immunoreactivity was found in thick ascending limbs of Henles loop, distal tubules and collecting ducts, whereas PLAGL1 expression in proximal tubules and renal corpuscles (including podocytes) was moderate and weak, respectively. By the in sillico screening of promoter sequences for PLAGL1 specific DNA-binding sites GGG-GCCCC we designated 43 candidate genes for PLAGL1-regulated genes. Analysis of their functional annotations identified three significantly over-represented gene sets: inositol phosphate metabolic processes (GO), endocrine and other factor-regulated calcium reabsorption (KEGG) and calcium signaling pathways (KEGG). CONCLUSION Differences in the renal expression of PLAGL1 suggest that this protein may be involved in the regulation of several cellular pathways both as transcriptional factor and coactivator/corepressor of other tran-scription factors reflecting its role in the cell type-specific control of gene expression.

DIAGNOSTIC DIFFICULTIES IN ALK+ ANAPLASTIC LARGE T-CELL LYMPHOMA IN CHILDREN

Introduction. Lymphomas account for about 12% of malignant tumors in children, and anaplastic lymphoma for 10–20% of Hodgkin’s and non-Hodgkin’s lymphomas. Clinical symptoms associated with malignant tumors of the lymphatic system are not specific. Diagnosis of these tumors is particularly difficult in the absence of a visible tumor or enlarged peripheral lymph nodes, especially when the symptoms may sug gest other, far more common diseases such as infections. Extensive clinical diagnostic procedures, including the exploratory laparotomy, intensive symptomatic treatment and antibiotic therapy do not explain the nature of the disease, do not improve the condition of a patient and lead to the death of sick children. In these cases only an autopsy and histopathological examinations demonstrate the presence of anaplastic large T-cell lymphoma’s infiltrates of internal organs, bone marrow and lymph nodes. Aim. The aim of this study was to demonstrate that in the diseases of children in which it is difficult to establish a definite clinical diagnosis and an intensive antibi otic therapy does not cause any improvement, a neoplastic disease should be always taken into consideration. Materials and methods. Analysis of the histo-clinical picture of a disease of a child who died due to ALK+ anaplastic large T-cell lymphoma. Diagnostic difficulties re sulted in not establishing a clinical diagnosis. Despite conservative treatment, surgical procedure and an intensive antibiotic therapy, the death occurred. The diagno sis was established post-mortem on the basis of immunohistochemical tests: LCA, CD30, CD43, Granzyme B, ALK, CD20, CD3, MPO and Ki67.

Histiocytic sarcoma imitating tumor of the pancreatic tail – a case study

Abstract Introduction Histiocytic sarcoma (HS) is a very rare and diagnostically difficult malignant neoplasm arising from dendritic cells and histiocytes. Its microscopic image is not specific, so the diagnosis of HS requires a wide panel of immunohistochemistry tests to exclude tumors with similar morphology, but of completely different origins. While diagnosing HS, cancers, other sarcomas, lymphomas and malignant melanoma should be excluded as well. Aim The aim of this paper was to present a case of HS imitating tumor of the pancreatic tail in a 58-year-old woman. Case study Intraoperative diagnosis was as follows: solid-cystic tumor of the pancreatic tail region, penetrating into the mesocolon and occluding the colon by pressing against it. Resection of the pathologic mass and tail of the pancreas, as well as total colectomy were performed. On the basis of postoperative histopathologic evaluation of the surgical specimen and a wide immunohistochemical panel, we excluded epithelial and myogenic origins of the tumor. Gastrointestinal stromal tumor, extramedullary myeloid tumor, lymphoma, neural tumors and malignant melanoma were also excluded. Histopathologic and immnohistochemical findings, compared to other authors’ findings led us to the diagnosis of histiocytic sarcoma. Complete resection of the tumor was performed, with sufficient margins of the healthy tissues. Physical examination and imaging performed three months after the surgery revealed features of the local recurrence, infiltration of the back wall of the stomach with a major compression of the gastric lumen. Metastatic foci in regions of left appendages and lower pole of the left kidney, multiple small hypodensic areas in the liver and enlarged paraaortal and mesenterial lymph nodes were also found. Discussion HS is a very rare and diagnostically difficult malignant tumor. Microscopic image is non-specific, that is why the diagnosis of HS requires a wide histochemical panel to exclude tumors with similar morphology, but of completely different origins. Analysis of negative immunohistochemical studies, results of: CD68, LCA(CD45), CD4, CD30, CD31, Fascin, CD43, CD15, CD34, and comparing them with the results obtained by other authors led us to the diagnosis of HS. Clinical prognosis is negative and the most frequent course of the disease is aggressive. Conclusions 1. Despite the rare prevalence of the tumor, there are numerous, well documented and immunohistochemically confirmed reports of histiocytic sarcoma and its gastrointestinal localization. That is why in a differential diagnosis of gastrointestinal tract-located tumors, sporadically occuring neoplasms should be also taken into account. 2. Diagnosis of HS requires a wide panel of immunohistochemistry tests to exclude tumors with similar morphology, but of completely different origins. 3. Recurrence of a neoplastic process in the described case confirms that, despite a surgical and microscopically total excision of the tumor, HS prognosis is negative and the course of the disease is very aggressive.