Background Peritoneal dissemination is the most common pattern of metastasis in advanced gastric carcinoma with serosal invasion In the present study, we reported the clinical relevance of a new diagnostic method involving RT-PCR, using su rvivin as the target gene, for the detection of free cancer cells in peritoneal washes Methods Intraoperative peritoneal washes were obtained from 48 patients who underwent su rgery for gastric cancer RT-PCR analysis with primers specific for survivin and conventional cytological examinations were both performed Results Su rvivin mRNA was not detected in any peritoneal wash samples from patients with benign disease, but was detected in 28 of 48 samples taken from patients with gastric cancer and in all metastastic nodules Survivin expression in the peritoneal cavity significantly correlated with depth of cancer invasion, lymph node etastasis, and TNM stage There were 92% of clinically evident peritoneal metastasis cases showed detectable su rvivin expression The combination of survivin RT-PCR and cytological examination yielded positive results in 66 7% (32/48) of patients with gastric cancer, much higher than the results produced by cytological method alone Conclusions Survivin mRNA detected in peritoneal lavage fluid might indicate the presence of free cancer cells in the peritoneal cavity. The high sensitivity of the RT-PCR-based survivin assay suggests that su rvivin serves as a molecular marker for detecting peritoneal micrometastasis Its ubiquitous expression in peritoneal cancer cells and metastatic nodules also suggests a promising future therapeutic strategy based on su rvivin inhibition for cases of gastric cancer involving peritoneal metastasis

AIM: Survivin, a recently identified member of the inhibitor of apoptosis protein family, is expressed during development and in various human cancers. However, its expression in normal tissues and clinical relevance in cancers are still debated. In the present study, we analyzed the expression of the survivin gene in human primary and metastatic gastric cancer cells as well as in paired epithelial cells from normal gastric mucosa by means of a novel laser capture microdissection (LCM) technique coupled with reverse transcription-polymerase chain reaction (RT-PCR). METHODS: Thirty patients who had undergone gastrectomy with lymph node dissection for gastric cancer without preoperative treatments were included. Neoplastic tissue, metastatic lymph nodes, and apparently uninvolved normal tissue were collected from each patient. LCM-captured "pure" cell groups were espectively subjected to RT-PCR analysis with primers specific for the survivin gene. RESULTS: Of the paired samples from 30 gastric cancer patients studied, 24 (80%) primary gastric cancer cell groups and 7 (23%) adjacent morphologically "normal" gastric epithelial cell groups were shown to have a detectable survivin expression. There was a statistically significant difference in suvivin expression between these two groups (P<0.01). Meanwhile, 95% (19/20) of the metastatic gastric cancer cell groups from lymph nodes had a clear expression of the survivin gene. However, no significant correlation between survivin expression and clinicopathological features of gastric cancer was bserved in the present study.CONCLUSION: Survivin expression is present in the majority of gastric cancer cell groups obtained by LCM techniques. The high expression rate in metastatic lesions suggests a possible role of survivin in cancer invasiveness and metastasis. It may contribute to the detection of gastriccancer micrometastasis as a potential molecular marker. In addition, the high expression percentage renders survivin a potential target in the therapy for gastric cancer.

We examined loss of heterozygosity (LOH) at the retinoblastoma susceptibility gene (RB1) locus on chromosome 13q14 in 20 non-small-cell lung cancers (NSCLCs) using polymorphic markers. The expression of RB protein was examined by immunohistochemical analysis of paraffinembedded specimens of the same tumors. The results revealed that 10 of 16 informative cases showed an LOH at the RB1 locus, whereas only 2 of the 10 tumors lost expression of the RB protein. These 2 tumors had mutations in the remaining RB1 allele. Thus, inactivation of the RB1 gene appears to be involved in a small subset of NSCLCs only. To elucidate the presence of tumor-suppressor genes other than RB1 on 13q, heterozygosity at 15 different loci was investigated. Of 20 tumors analyzed, 15 showed an LOH at least at one locus, and the regions 13q12.1-qter, 13q12.2-14.2 and 13q14.1-q14.3, including the RB1 locus, were deleted in significant numbers of the tumors. Our results suggest that, in addition to the RB1 gene, abnormalities of other tumorsuppressor genes on chromosome 13q are involved in the development of human NSCLCs. Int. J. Cancer 74: 45-49.

应用重组技术构建野生型及缺失型CDK2基因的真核表达载体，分别使野生型及缺失型CDK2蛋白与增强型绿色荧光蛋白（Enhanced-green Fluorescent Prutein, EGFP）形成融合蛋白。通过脂质体介导的方法将载体转染人宫颈癌细胞系HeLa和中华仓鼠卵巢细胞系CHO，经过细胞周期同步化处理后于荧光显微镜下观察EGFP的亚细胞定位以示踪野生型及缺失型CDK2基因的表达。结果表明，野生型CDK2基因的表达产物定位于细胞核，而两种缺失型CDK2基因分别编码的CDK2蛋白N-端1～201及98～298多肽均主要定位于细胞质。以上结果提示，CDK2蛋白序列中不含有与核定位直接相关的信号，其入核过程可能是由其N-端1～97及202～298多肽范围内的部分氨基酸共同形成高级结构，并依赖此高级结构与其他含有入核信号的蛋白形成复合物，从而被带动进入细胞核的。