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B Gunawan

Publications and source records attributed to B Gunawan.

At least 37 records · Page 2Linked to original sources
PubMed2000

Genomic structure and in vivo expression of the human organic anion transporter 1 (hOAT1) gene.

The human organic anion transporter 1 (hOAT1) plays a key role in the secretion of an array of potentially toxic organic anions including many clinically important drugs. Here we report on the genomic cloning of hOAT1. A human genomic library was used for screening of a PAC (P1 artificial chromosome) clone applying PCR techniques. Sequencing of several restriction subclones and of a PCR-generated clone revealed that the hOAT1 gene spans 8.2 kb and is composed of 10 exons divided by 9 introns. RT-PCR studies in a human kidney specimen led to the detection of two new splice variants, hOAT1-3 and hOAT1-4, showing a 132-bp in-frame deletion. Using fluorescence in situ hybridization (FISH) we mapped the hOAT1 gene as a single signal to chromosome 11q13.1-q13.2. Additionally, 600 bp of the 5' flanking region was analyzed, illustrating the probable transcription start site at nt -280, a NF-kappaB-site at nt -397 and several putative transcription factor binding sites.

Anion Transport Proteins↗
PubMed2000

Clonal chromosome abnormalities in enchondromas and chondrosarcomas.

We report cytogenetic findings in short-term cell cultures from five enchondromas and four chondrosarcomas. Clonal chromosome aberrations were found in one case of enchondroma, and in all cases of chondrosarcoma. The only enchondroma with nonrandom abnormalities had a reciprocal t(8;17)(q23;p13), and monosomies 9, 19, and/or 22. In contrast to the few karyotypic findings in one of five enchondromas, the four chondrosarcomas were commonly characterized by cytogenetic heterogeneity, with a tendency for increasing karyotypic complexity in higher grade tumors. Two cases, one grade III and one metastasizing grade II chondrosarcoma, revealed hypodiploid stem- and sidelines with loss of chromosomes 6, 10, 13, 14, and 22, as common chromosomal abnormalities, suggesting a distinct karyotypic pattern in a subset of biologically aggressive chondrosarcomas.

Adolescent↗
PubMed2000

Cytogenetic and DNA-fingerprint characterization of choriocarcinoma cell lines and a trophoblast/choriocarcinoma cell hybrid.

We report the successful fusion of human choriocarcinoma cells with normal human trophoblast cells to a choriocarcinoma/trophoblast hybrid. The hybrid cells ACH1P were derived from fusion of primary male trophoblast cells with the HGPRT-defective choriocarcinoma cell line AC1-1. The karyotypes of the parental choriocarcinoma cell line JEG-3, its HGPRT-defective mutant clones AC1-1, AC1-5, and AC1-9, and the choriocarcinoma/trophoblast hybrid ACH1P are presented, together with a detailed characterization of the AC1-specific chromosomal marker add(X)(q26) using conventional cytogenetic banding techniques and multiplex-fluorescence in situ hybridization (M-FISH). To our knowledge, this is the first report of a stably proliferating human cell hybrid of trophoblastic origin, providing a unique cell culture model to study trophoblast-related invasion and its underlying genetic mechanisms.

Cell Fusion↗
PubMed2000

[Undifferentiated small-cell hepatoblastoma].

Undifferentiated small-cell hepatoblastoma (HB) is a rare malignant tumor of childhood. The cell of origin is supposed to be a pluripotential, probably entodermal, stem-cell. Differential diagnosis of this type of HB is difficult among the group of small round and blue cell malignant tumors of children. The immunohistochemically determined coexpression of cytokeratin 8, 18, and 19 and of vimentin and actin, regularly in the absence of alpha-fetoprotein expression may be diagnostically helpful. We present the case of an undifferentiated small-cell HB of a 15-month-old girl with agenesis of the right kidney. As morphological peculiarity the tumor presented disseminated histiocytic giant cells.

Actins↗
PubMed1999

Inflammatory pseudotumor of the diaphragm.

A 5-year-old-boy presented with a right pleural effusion and fever. A tumorous mass was located between the right lung and the liver. The boy underwent a right thoracotomy with excision of the tumor and the adherent parts of the right hemidiaphragm. Histology and immunohistochemistry showed an inflammatory pseudotumor of the diaphragm. This is the first reported case of an inflammatory pseudotumor in this location. A brief review of the heterogeneous theories about the pathogenesis and the different therapeutic regimens for this rare neoplastic entity are discussed.

Biopsy↗
PubMed1999

Polyploidization and losses of chromosomes 1, 2, 6, 10, 13, and 17 in three cases of chromophobe renal cell carcinomas.

Clonal chromosome aberrations identified after short-term culture are presented for three cases of chromophobe renal cell carcinomas (RCC). All tumors revealed abnormal karyotypes with a varying proportion of polyploid tumor cells. Common numerical abnormalities were combined losses of chromosomes 1, 2, 6, 10, 13, and 17. Clonal karyotypic evolution was demonstrated in one case in which several related clones could be identified. An additional balanced translocation t(3;14)(p24;q22) observed in this case proved to be of constitutional nature by cytogenetic analysis of normal kidney cells and peripheral blood lymphocytes. These cytogenetic findings provide further evidence that chromophobe renal cell carcinomas are characterized by a highly specific combination of chromosomal losses most commonly including chromosomes 1, 2, 6, 10, 13, and 17.

Adenocarcinoma↗
PubMed1999

Papillary renal cell carcinoma with clear cell cytomorphology and chromosomal loss of 3p.

AIMS: Cytogenetic studies on renal cell carcinomas (RCCs) have disclosed a correlation between chromosome aberrations and histomorphological features. Nevertheless, it is still controversial whether the cytomorphology of the tumour cells (clear cell, chromophilic, chromophobe) or their growth pattern (nonpapillary, papillary) is more discriminative for the combined histomorphological-cytogenetic classification of RCCs. METHODS AND RESULTS: Three RCCs with papillary growth pattern and clear cell cytomorphology were analysed by classical cytogenetics using standard G-banding techniques. Each tumour displayed clonal aberrations leading to loss of terminal 3p chromosomal segments. Monosomy 14 was also consistently found. Trisomy 17 was not observed in any of the tumours. CONCLUSIONS: This series of three RCCs consisting of clear cells with papillary architecture revealed chromosomal aberrations characteristic for the conventional (clear cell) RCC. Irrespective of the predominant papillary growth pattern, none of the cases were characterized by trisomy of chromosomes 3q, 7, 8, 12, 16, 17 and 20 and loss of Y chromosome which are widely regarded as the most consistent genetic alterations for papillary RCC. Therefore, our cytogenetic findings provide evidence that papillary clear cell RCCs should be classified according to their cytomorphology rather than their growth pattern even when papillary architecture is prominent.

Adult↗
PubMed1999

Clinical aspects of alveolar rhabdomyosarcoma with translocation t(1;13)(p36;q14) and hypotetraploidy.

Although most cases of alveolar rhabdomyosarcoma (RMS) are characterized by the chromosomal translocation t(2;13)(q35;q14), several cases have been reported with a variant t(1;13)(p36;q14). We present the clinical, morphological and cytogenetic features of an alveolar RMS in a 4-year-old boy. Chromosomal analysis revealed a hypertriploid to hypotetraploid karyotype with a t(1;13)(p36;q14) in all tumor cells. It appears that alveolar RMS with t(1;13) occurs in younger children and displays a higher incidence to upper and lower extremity than tumors with t(2;13).

Aneuploidy↗
PubMed1998

Characterization of a newly established endometrial stromal sarcoma cell line.

We describe a newly established human sarcoma cell line derived from an endometrial stromal sarcoma (ESS). The cell line has been maintained in long-term cell culture for more than 2 years. It has been repeatedly analyzed in terms of morphology, immunocytochemical features, ultrastructure and karyotypic characteristics. In contrast to uniform endometrial stromal differentiation in vivo, the tumor cells were shown to display distinct phenotypical heterogeneity in vitro. In addition to the predominant cell type, which retained sarcomatous differentiation, foci of epithelial-like cells were observed in the cell culture. Immunocytochemical and ultrastructural analysis demonstrated a mainly mesenchymal phenotype with signs of epithelial characteristics, such as expression of cytokeratins, and the presence of desmosomes and kinetocilia, respectively. Cytogenetic analyses in early and late passages revealed unbalanced translocations between chromosomes 3 and 6 and an additional i(19)(q10), as common karyotypic changes in all tumor cells, indicating a monoclonal origin. Our new cell line can be used as an in vitro model to study the mechanisms of heterogeneous differentiation patterns in ESS.

Aged↗
PubMed1998

Solitary enchondroma with clonal chromosomal abnormalities.

We report a case of a solitary enchondroma located in the head of the left fibula in a 50-year-old patient and present the findings of histopathologic investigation and cytogenetic analysis. The tumor revealed simple karyotypic abnormalities with t(8;17)(q23;p13) and loss of chromosomes 9, 19, and 22 as clonal chromosomal changes. Only a few enchondromas with chromosome aberrations have been published previously; nevertheless, it appears that benign and malignant cartilaginous tumors may have similar chromosomal abnormalities.

Bone Neoplasms↗
PubMed1998

Cytogenetic analysis of 11 renal oncocytomas: further evidence of structural rearrangements of 11q13 as a characteristic chromosomal anomaly.

We carried out cytogenetic analysis on 11 renal oncotytomas by using G-banding and DAPI-banding techniques. Four of our tumors exhibited structural rearrangements affecting chromosome 11 at band q13. Together with another case previously described by us, our tumors constitute the largest series of renal oncocytomas displaying translocations involving 11q13. A review of the literature disclosed only 6 similar oncocytomas, 1 tumor with a t(9;11)(p23;q12), 2 tumors with a nearly identical t(9;11)(p23;q13), and 3 tumors with a t(5;11)(q35;q13). Therefore, our findings provide further cytogenetic evidence that genes located on 11q12-13 may be involved in the tumorigenesis of renal oncocytomas.

Adenoma, Oxyphilic↗
PubMed1998

A cytogenetic approach to the differential diagnosis of metastatic clear cell renal carcinoma.

AIMS: To determine by cytogenetic analysis the origins of two clear cell tumours in a 70-year-old Caucasian woman, one in the thyroid gland, and the other in the skin, 16 and 20 years, respectively, after tumour nephrectomy. We sought a conclusive distinction between primary clear cell thyroid carcinoma and its cutaneous metastasis, and between thyroid and cutaneous metastases of clear cell renal carcinoma (RCC). METHODS AND RESULTS: Paraffin sections of the previously formalin-fixed thyroid tumour, and the fresh cutaneous tumour were stained with haematoxylin and eosin (H & E) and periodic acid-Schiff (PAS). Additionally, samples of both tumours were examined electron microscopically. Immunohistochemistry was performed with antibodies against thyroglobulin, pancytokeratin, keratin 7, 8, 18 and 19, chromogranin, calcitonin, CEA, vimentin and EMA. Five to six micrometre sections of both tumours were analysed with alpha-satellite probes of chromosomes 3, 7 and 17 using chromosomal in-situ hybridization (CISH). The cutaneous tumour was also cultured and analysed cytogenetically. The thyroid tumour displayed some follicle-like structures that stained positive with both PAS and antithyroglobulin, giving evidence of possibly entrapped thyroid follicles in metastatic RCC. The cutaneous tumour was negative for both stains. The tumours were ultrastructurally completely devoid of neurosecretory granules. Classical cytogenetical analysis of the cultured cutaneous tumour cells revealed monosomies 3 and 14, well-known specific primary and secondary aberrations, respectively, in clear cell RCC, and hitherto not reported in thyroid carcinomas. CISH of both tumours revealed monosomy 3, indicating a cytogenetical correlation between them. There was no evidence of typical chromosomal aberrations for thyroid carcinomas like structural changes on 10q, structural rearrangements or translocations of chromosome 7. CONCLUSION: Although neither histological sections, nor paraffin blocks of the original nephrectomy specimen were available for review, the original tumour was on record as clear cell RCC. Therefore the two tumours' renal origin was confirmed.

Aged↗
PubMed1998

[Ultrastructural differential diagnosis of gastrointestinal stromal tumors].

Gastrointestinal stromal tumors (GIST) may present with myogen or neurogen differentiation, mixed differentiation or with morphological features which cannot be further specified. 14 GIST of the stomach (9), the duodenum (2) and small bowel (3) were examined by immunohistochemistry and electron microscopy. Diagnosis was consistent for such tumors located distally from the stomach, however, evaluation of GIST of the stomach was different (apart from one case). Light microscopy and immunohistochemistry did not allow to discriminate between the different subtypes of GIST, however, electron microscopy revealed cellular differentiation. Hence, ultrastructural analysis is an useful tool for diagnosis of GIST, particularly those of the stomach.

Adult↗
PubMed1998

Cytogenetic and morphologic characteristics of gastrointestinal stromal tumors. Recurrent rearrangement of chromosome 1 and losses of chromosomes 14 and 22 as common anomalies.

We present cytogenetic findings in five gastrointestinal stromal tumors (GISTs). Three of these five cases had abnormal karyotypes with clonal chromosomal aberrations. The most common karyotypic pattern was a combined loss of chromosomes 14 and 22 in a total of three cases. Among these cases, additional recurrent chromosomal abnormalities were loss of 1p and/or 9, detected in two cases each. Another karyotypic feature consisted of polyploidisation, leading to hypotetraploid chromosome numbers in one case. These cytogenetic results provide evidence for a characteristic karyotypic pattern consisting of -14 and -22 in a subset of GISTs.

Chromosome Aberrations↗
PubMed1995

Endometrial stromal sarcoma with clonal chromosomal aberrations and mixed phenotype.

We report a case of a moderate-grade endometrial stromal sarcoma with the following chromosomal complement based on the evaluation of 43 metaphases: 47,XX,der(3)t(3;6)(q29;p21.1),der(6) t(3;6)(q21;q27), + 19. Immunohistochemically, the paraffin-embedded tumor tissue displayed positive vimentin reactivity and lack of cytokeratin expression, indicating a mesenchymal origin. Interestingly, the cultivated tumor cells revealed a co-expression of vimentin and different subtypes of cytokeratin. Therefore, the cytogenetically monoclonal tumor cells which showed co-expression of epithelial and mesenchymal phenotypes suggest that the endometrial stromal sarcoma can be interpreted as a monophasic variant of the malignant mixed Müllerian tumor.

Aged↗
PubMed1994

Renal oncocytoma with a translocation t(9;11)(p23;q13).

We report a case of renal oncocytoma and confirm a tumor type specific translocation between chromosomes 9 and 11, that is t(9;11)(p23;q13q23). Each of the 45 cytogenetically analyzed metaphases of tumor cells showed a translocation of the long arm of chromosome 11 at q13 to chromosome 9 at 9p23 and to chromosome 20 at 20q13 that resulted in the following karyotype: 46,XX,der(11)ins(9;11)(p23;q13q23)ins(20;11)(q13;q23q25),del (22q13). Since genes encoding mitochondrial enzymes are clustered around the translocation site of chromosomes 11 and 20, they may have a role in the tumorigenesis of renal oncocytoma. In addition, if the development of oncocytomas shows different cytogenetic pathways the cytogenetic aberration of t(9;11)(p23;q12q13) can be of diagnostic help in differentiating a subset of oncocytoma from renal cell carcinoma.

Adenoma, Oxyphilic↗
PubMed1994

Cytogenetic findings in squamous cell carcinoma of the oral cavity.

A case of squamous cell carcinoma (SCC) of the oral cavity is presented which, in addition to normal metaphases, cytogenetically displayed two cell clones with chromosomal aberrations: 46,XY,1+del(5)(q13),der(18)t(5;18)(q13;p11),-5 and 49,XY,+5,+7,+10 After a review of the literature of the few cytogenetically analyzed cases, the findings confirm the multiclonal origin of oral SCC and also the commonly seen aberrations of chromosome 5.

Aged↗