Effect of Bcl-2 antisense oligonucleotide on drug-sensitivity in association with apoptosis in undifferentiated thyroid carcinoma

Although attempts have been made to treat undifferentiated thyroid carcinoma using multidisciplinary therapeutic procedures including surgery, radiotherapy, and chemotherapy, the prognosis of undifferentiated thyroid carcinoma remains quite poor. New approaches to increase the sensitivity of patients to anticancer drugs and radiation will be needed to improve the survival rate for undifferentiated thyroid carcinoma. We examined the effect of Bcl-2 antisense oligonucleotide on drug-sensitivity in association with apoptosis in the 8305C undifferentiated thyroid carcinoma cell line. The drug sensitivity was evaluated by MTT assay for 48 h, while apoptosis was assessed according to the formation of internucleosomal DNA ladders. The Bcl-2 antisense was introduced into 8305C cells by using a 18-mer phosphorothioate oligonucleotide by lipopolyamine-mediated transfection twice for 12 h. The expression of apoptosis genes was assessed by Western blotting. The 8305C cells were sensitive to adriamycin (ADM), mitomycin (MMC), docetaxel (TXT), and paclitaxel (TXL), showing mean IC50 values of 0.72, 1.1, 1.3, and 4.1 microM, respectively. In contrast, the 8305C cells were resistant to cisplatin (CDDP) and 5-fluorouracil (5-FU), with mean IC50 values of 42.0 and 48.0 microM, respectively. Treatment with Bcl-2 antisense suppressed the protein level of Bcl-2 in 8305C cells in a dose-dependent manner up to 1.0 microM. Drug-sensitivity was increased by pretreatment with Bcl-2 antisense as assessed by the IC50 (x-fold): 0.48 (1.5-fold) in ADM; 0.42 (2.6-fold) in MMC, 0.56 (2.3-fold) in TXT, 1.5 (2.7-fold) in TXL, 8.6 (4.9-fold) in CDDP, and 25.0 (1.9-fold) in 5-FU, respectively. The increased drug-sensitivity was associated with the induction of apoptosis-related proteins, Fas, caspase 8, cytochrome c, caspase 3, and to subsequent apoptosis, as determined by the formation of internucleosomal DNA ladders and PARP in the treated cells. Susceptibility in apoptotic cell death following treatment with anticancer drugs was associated with induction of apoptosis-related genes in undifferentiated thyroid carcinoma cells, and induction of apoptosis was enhanced by pretreatment with Bcl-2 antisense oligonucleotide. These results imply a potential new strategy targeting an antiapoptotic protein, Bcl-2, by its antisense oligonucleotide for enhancement of chemotherapeutic efficacy in undifferentiated thyroid carcinomas.     

IMMUNOHISTOCHEMICAL STUDY OF PANCREATOBLASTOMA

Three cases of pancreatoblastoma in children were examined immunohis-tochemically and the results were compared with those of pancreatic duct carcinoma in adults. The pancreatoblastoma demonstrated positive reactions to α-fetoprotein (AFP) (67%: 2/3), α-1-antitrypsin (AAT) (100%: 3/3), carcinoembryonic antigen (CEA) (67% : 2/3) and keratin (33% : 1/3), although CEA was only weakly positive in both cases. On the other hand, adult pancreatic duct carcinoma showed positive reactions as follows; AFP: 3% (1/29), AAT: 21% (6/29), CEA: 97% (28/29) and keratin: 93% (27/29). Also, endocrine substances including insulin, glucagon and somatostatin were all negative in the pancreatoblastomas. Two cases of pancreatoblastoma which were immunohistochemically positive for AFP also showed elevation of the serum AFP level clinically. The different expressive pattern of oncofetal antigens in pancreatoblastoma as compared with pancreatic duct carcinoma in adults may provide further supporting evidence for the embryonic nature of pancreatoblastoma, and suggests that such a pattern might be used as a tumor marker for pancreatoblastoma. ACTA PATHOL. JPN. 37 : 1581-1590, 1987.     

AN ULTRASTRUCTURAL STUDY OF EXTRASKELETAL MESENCHYMAL CHONDROSARCOMA

A rare case of extraskeletal mesenchymal chondrosarcoma in a 47-year-old woman is reported. The tumor was located in the soft tissue of left upper arm without any involvement of the humerus. The outer portion of the tumor was histologically composed of primitive mesenchymal cells, and the inner portion showed zones of cartilaginous differentiation. Ultrastructurally, the tumor cells in the primitive areas had a relatively small number of mitochondria, rough endoplasmic reticulum, and free polysomes, and the matrix of the tumor consisted of dense bundles of collagen fibrils. The cartilaginous cells seen in the central portion of tumor were embedded in the matrix of abundant collagen fibrils and matrix granules. They had polysomes, well-developed Golgi complexes, and ample rough endoplasmic reticulum frequently with dilatation. Clear zones adjacent to the cells were seen in the extracellular matrix. With a review of the literature, the histogenesis of this particular tumor is discussed. ACTA PATHOL. JPN. 34: 1355–1363, 1984.     

Ras P21 EXPRESSION IN NEPHROBLASTOMA GROUP TUMORS

Ras p21 expression in 30 cases of nephroblastoma and related tumors was evaluated by the immunoperoxidase method using monoclonal anti- ras p21 antibody (RAP-5) raised against a synthetic polypeptide fragment of ras p21. In normal renal tissue, the epithelial cells of convoluted and collecting tubules and arterial wall leiomyocytes were positively stained. In nephroblastoma tumors, some of the epithelial cells forming primitive tubular and glomerular-like structures in the nephroblastic-type tumors and the cells with including intimal features were positive. However, the epithelial cells in more differentiated glandular structures of epithelial-type tumors, the rhabdoid cells in rhabdoid tumors and the cells in congenital mesoblastic nephroma failed to show positive staining. Nephroblastic cells, stromal cells and sarcomatous cells were also negative.     

Two cases of a renal epithelial tumour resembling immature nephron

Summary Two cases of renal epithelial tumours are reported in females aged 46 and 66 years respectively. In spite of the large size of the tumours, neither invasive growth nor metastasis was observed. Histologically, the tumours were composed of immature epithelial cells forming tubules with abortive glomeruloid structures. Electron microscopy of tumour cells revealed poorly developed polarity and intracytoplasmic organelles. They showed similar immunohistochemical reactions to those of developing nephrons, particularly to those of the S-shaped body. The nuclear DNA content of the tumour cells was almost euploid. We conclude that the lesions were epithelial tumours of the kidney histologically mimicking developing renal parenchyma.     

Balloon cell nevus of the soft palate: an immunohistochemical and ultrastructural study

An ultrastructural analysis of oral balloon cell nevus of intramucosal type complemented with an immunohistochemical study was performed for the first time. The lesion was composed of large balloon cells with an admixture of small nevus cells and melanophages at the periphery. Balloon cells showed cytoplasmic accumulation of vacuoles of varying sizes and the presence of microgranular and vacuolated melanosomes were found. Residual cytoplasm contained no identifiable organelles. A spectrum of transitional forms between balloon cells and conventional nevus cells with microvacuoles was readily observed. Both cells exhibited intense immunoreactivity to multiple melanocytic markers. Ballooning phenomenon was not evident in melanophages containing a large amount of melanosome complex. It can be inferred, from the present and previous observations, that progressive vacuolization of melanosomes in nevomelanocytes may be responsible for the formation of peculiar ballooning appearance, suggesting an aberrant melanogenesis.     

Diagnostic utility of galectin-3 and CD26/DPPIV as preoperative diagnostic markers for thyroid nodules

The aim of this study was to search for diagnostic markers that could correctly identify thyroid nodular lesions requiring urgent surgical treatment. We investigated whether galectin-3 and dipeptidyl peptidase IV (CD26/DPPIV) could be potential markers for improving the diagnostic accuracy of conventional cytology. Seventy-nine patients with histologically proven thyroid diseases were analyzed. The immunocytochemical staining results showed galectin-3 expression in neoplastic cells of all 37 papillary carcinomas, five of six follicular carcinomas, all three anaplastic carcinomas, one of three medullary carcinomas, and two of 14 follicular adenomas. All 16 adenomatous goiters were negative for galectin-3 immunostaining. On the other hand, all 37 papillary carcinomas, all six follicular carcinomas, and one of three anaplastic carcinomas revealed CD26/DPPIV expression, whereas all three medullary carcinomas were negative. Among benign thyroid lesions, four of 14 follicular adenomas and two of 16 adenomatous goiters exhibited varying degrees of immunoreactivity for CD26/DPPIV. RT-PCR analysis demonstrated overexpression of galectin-3 and CD26/DPPIV mRNAs in all six papillary and all three follicular carcinomas analyzed, whereas the mRNA expressions of these molecules were barely or not detectable in benign thyroid lesions and normal thyroid tissues, except for one case of follicular adenoma. In conclusion, we demonstrate that galectin-3 and CD26/DPPIV were consistently coexpressed at protein and mRNA levels in differentiated thyroid carcinomas. We propose that combined immunostaining for galectin-3 and CD26/DPPIV in the preoperative evaluation of thyroid nodules may play a role in accurate cytodiagnosis.     

Polymeric chiral crown ethers, 4. Substituent effects of methyl and phenyl groups in the 3,3′-positions on chiral recognition of poly(crown ether)s synthesized by cyclopolymerization of divinyl ethers derived from 1,1′-bi-2-naphthol

Chiral poly(crown ether)s were synthesized by cationic cyclopolymerization of (S)-2,2′-bis(2-vinyloxyethoxy)-3,3′-dimethyl-1,1′-binaphthyl [(S)- 1b ] and (R)-2,2′-bis[2-(2-vinyloxyethoxy)-ethoxy]-3,3′-dimethyl (or 3,3′-diphenyl)-1,1′-binaphthyl [(R)- 3b or (R)- 3c ]. The substituents in the 3,3′-positions of binaphthyl moiety disturb the intramolecular cyclization in the polymerization of monomer (S)- 1b , but have no influence on the cyclopolymerization tendency of monomers (R)- 3b and (R)- 3c . The polymers from (R)- 3b and (R)- 3c [(R)- 4b and (R)- 4c ] have a higher ability of chiral recognition towards a-amino acids, such as phenylglycine, phenylalanine, valine, and methionine, than the polymer from (R)- 3a [(R)- 4a ], which has no substituent in 3,3′-positions. The methyl and the phenyl substituents in the 3,3′-positions undoubtedly act as additional barrier causing an increase in the ability of chiral recognition, though the effect is less than expected from the result of model crown ethers.