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A 29-year-old Thai man presented with progressive dyspnea and evidence of pulmonary hypertension. Computed tomography was negative for pulmonary embolism. Cardiac catheterization confirmed the diagnosis of pulmonary arterial hypertension (mean pulmonary artery pressure 54?mm Hg, left ventricular end-diastolic pressure 4?mm Hg, and pulmonary vascular resistance 25 Wood units) without an intracardiac shunt. Two family members had been previously diagnosed with pulmonary hypertension. There was no evidence of left heart disease or respiratory disorders. Based on the definite diagnosis of pulmonary hypertension in 3 family members, heritable pulmonary arterial hypertension was confirmed. Genetic testing indicated no BMPR2mutation.

Immunocytochemistry has indicated that, in the liver, the bcl-2 gene is generally expressed in bile duct cells and tumors of biliary origin. Both in situ hybridization and immunocytochemistry were used to analyze the expression of bcl-2 messenger RNA (mRNA) and its protein product (Bcl-2) in the tissue of 50 pure primary liver tumor (PLT) specimens including 40 hepatocellular carcinoma (HCC) specimens and 10 cholangiocellular carcinoma (CC) specimens. The phenotype of the tumors expressing bcl-2 was confirmed by immunocytochemical assessment of the cytokeratin (CK) profile (CK8, CK18, CK7, and CK19). Whereas positive immunoreaction with the anti-Bcl-2 MoAb was revealed in only 8 (20) of 40 HCC specimens and 1 (10) of 10 CC specimens, high contents of bcl-2 mRNA were found in 26 (65) of 40 HCC specimens and 9 (90) of 10 CC specimens. Regarding the CK profile, only 25 (62) of 40 HCC specimens showed pure hepatocytic lineage (CKs 8–18), whereas among the remaining 15 HCC specimens, positivity for either CK7 (12 specimens) or CK19 (5 specimens) was observed. All 10 CC specimens stained with CKs 8–18–19, and 8 of 10 stained with CK 7 as well. These results indicate that PLTs display a greater expression of bcl-2 mRNA than of the Bcl-2 protein. Furthermore, CK profile assessment confirmed that bcl-2 expression is not confined to liver tumors of biliary origin. In the absence of a well-demonstrated post-transcriptional control of the gene, the authors propose the detection of bcl-2 mRNA by in situ hybridization as a possible alternative method for assessing the expression of bcl-2 mRNA in PLT.

Extensive study of Bcl-2 protein expression in prostate cancer (CaP) tissues by means of immunocytochemistry (IC) has provided evidence that it positively correlates with high grade and stage of CaP and is associated with resistance to anti-androgen hormone therapy. In the present study, we investigated the expression of bcl-2 mRNA by non-isotopic in situ hybridization (ISH) in a series of 36 CaP with or without previous anti-androgen hormone treatment and performed a comparison with IC-detected Bcl-2 protein expression. Expression of Bcl-2 mRNA detected by ISH consistently differed from that detected by IC, especially in lymph node metastases (whereas no relevant variations of Bcl-2 mRNA levels were found in treated vs. untreated CaP patients). In particular, high content of Bcl-2 mRNA was found in 25/36 cases of CaP (in 13/18 hormone-treated and 12/18 untreated patients). Conversely, Bcl-2⁺ immunostaining was observed in only 7/36 CaP (in 4/18 hormone-treated and 3/18 untreated patients). Furthermore, ISH revealed Bcl-2 mRNA in 4/7 lymph node metastases, all 7 of which were Bcl-2^– by IC. We conclude that, in the absence of a demonstrated post-transcriptional control of the bcl-2 gene, detection of mRNA by ISH in prostate archival tissues appears to be a reliable alternative method to assess differential expressions of the bcl-2 gene. Int. J. Cancer (Pred. Oncol.) 79:614–618, 1998. © 1998 Wiley-Liss, Inc.