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Differential screening of the genes obtained from cDNA libraries of primary neuroblastomas (NBLs) between the favorable and unfavorable subsets has identified a novel gene BCH motif-containing molecule at the carboxyl terminal region 1 (BMCC1). Its 350 kDa protein product possessed a Bcl2-/adenovirus E1B nineteen kDa-interacting protein 2 (BNIP2) and Cdc42GAP homology domain in the COOH-terminus in addition to P-loop and a coiled-coil region near the NH2-terminus. High levels of BMCC1 expression were detected in the human nervous system as well as spinal cord, brain and dorsal root ganglion in mouse embryo. The immunohistochemical study revealed that BMCC1 was positively stained in the cytoplasm of favorable NBL cells but not in unfavorable ones with MYCN amplification. The quantitative real-time reverse transcription–PCR using 98 primary NBLs showed that high expression of BMCC1 was a significant indicator of favorable NBL. In primary culture of newborn mice superior cervical ganglion (SCG) neurons, mBMCC1 expression was downregulated after nerve growth factor (NGF)-induced differentiation, and upregulated during the NGF-depletion-induced apoptosis. Furthermore, the proapoptotic function of BMCC1 was also suggested by increased expression in CHP134 NBL cells undergoing apoptosis after treatment with retinoic acid, and by an enhanced apoptosis after depletion of NGF in the SCG neurons obtained from newborn mice transgenic with BMCC1 in primary culture. Thus, BMCC1 is a new member of prognostic factors for NBL and may play an important role in regulating differentiation, survival and aggressiveness of the tumor cells.Oncogene (2006) 25, 1931–1942. doi:10.1038/sj.onc.1209225; published online 14 November 2005 [ABSTRACT FROM AUTHOR]

In a patient with gastric cancer (GC) associated with one synchronous and three metachronous hepatic metastases (HM), who underwent four hepatectomies, we carried out histochemical investigations regarding cell proliferation, apoptosis, and angiogenesis in the GC and HM. Tissue samples were taken from the primary GC and four HM. Ki-67 immunostaining was performed to evaluate cell proliferation and determine the labeling index (Ki-67 LI; ie, the percentage of cancer cells with nuclei stained for Ki-67). Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL) was performed to evaluate apoptosis and determine the apoptotic index (ie, the percentage of TUNEL-positive cells), and immunostaining for factor VIII-related antigen was performed to evaluate angiogenesis and measure microvessel density (MVD). The Ki-67 LI was 43.2% in the primary GC and 39.9% in the synchronous HM, and the LI increased with the number of resections of metachronous HM. The apoptotic index was 3.36% in the primary GC, and 5.30% in the synchronous HM, and the index decreased after further resections of the metachronous HM. The MVD was 35 in the primary GC, and 22 in the synchronous HM, and it increased with the number of resections of metachronous HM. The primary GC in this patient may have strongly influenced the growth of HM through effects on cell proliferation, apoptosis, and angiogenesis. [ABSTRACT FROM AUTHOR]

Accumulating evidence has demonstrated that aberration of the p53 tumour-suppressor gene is one of the pivotal genetic events in hepatocellular carcinogenesis. Recent reports suggest that the product of hepatitis B virus (HBV) interacts with p53 and that the hepatitis C virus (HCV) core protein reduces p53 expression. A novel p73 gene, which is related to p53, has recently been identified and mapped to chromosome 1p36.3, which is a locus of multiple tumour-suppressor genes for many cancers, including hepatocellular carcinoma (HCC) and neuroblastoma. Here, we investigated mRNA expression, allelotype and mutation of p73 in 48 HCCs obtained from untreated patients. Reverse transcriptase polymerase chain reaction (RT-PCR) revealed that p73 mRNA was expressed ubiquitously at low levels in all the tumour tissues, as well as in the adjacent normal liver tissues. The frequency of p73 loss of heterozygosity was observed in 20% of HCCs, but PCR-single strand conformation polymorphism (SSCP) analysis showed no mutations in the 48 tumours except for three types of polymorphisms. These results suggest that p73 may play a role in hepatocellular carcinogenesis in a different manner from a Knudson two-hit model. The regulatory mechanism of interaction between p73 and hepatitis viruses remains to be determined. [ABSTRACT FROM AUTHOR]