High levels of intracellular bombesin characterize human small-cell lung carcinoma

"Small cells" or "oat cells" characterize a virulent form of lung cancer and share many biochemical properties with peptide-secreting neurones. The neuropeptide bombesin is present in all small-cell lines examined, but not in other lung cancer cell lines, suggesting that bombesinergic precursor cells in lung may give rise to this disease.     

非小细胞肺癌与p16基因CpG岛异常甲基化的关系

目的 :探讨非小细胞肺癌中抑癌基因 p1 6的失活机制 ;方法 :采用甲基化特异性 PCR( MSP)法检测 30例非小细胞肺癌肿瘤组织、30例癌旁组织及 3例正常肺组织中 p1 6基因外显子 1的 Cp G岛异常甲基化情况。结果 :非小细胞肺癌中有 1 2例 ( 4 0 % )肿瘤组织检测到 p1 6基因 5’端 Cp G岛异常甲基化 ,而癌旁组织及正常肺组织均未检测到 p1 6基因的异常甲基化 ,两者之间差异有显著性 ( P<0 .0 0 1 )。结论 :p1 6基因 5’端 Cp G岛异常甲基化与非小细胞肺癌的发生发展有关 ,可能是该基因在非小细胞肺癌中的主要失活机制。     

非小细胞肺癌中MAGE-3蛋白的Western Blot分析

目的：观察黑素瘤抗原-3(MAGE-3)蛋白在非小细胞肺癌(NSCLC)中的表达。方法：用Western blot方法对3种人肺癌细胞系和56例NSCLC标本及相邻正常肺组织标本MAGE-3蛋白的表达情况进行研究。结果：3种人肺癌细胞系均表达MAGE-3蛋白;56例NSCLC标本中,28你表达MAGE-3蛋白,而相邻正常肺组织均不表达MAGE-3蛋白。结论：MAGE-3蛋白在NSCLC中有较高比率的表达．有望以该抗原作为适宜靶点对NSCLC患者进行免疫治疗。     

Growth regulation of human melanocytes: mitogenic factors in extracts of melanoma, astrocytoma, and fibroblast cell lines

Melanocytes derived from fetal or adult skin do not propagate in vitro unless cultured in the presence of factors such as 12-O-tetradecanoylphorbol 13-acetate (TPA). In a search for physiological factors regulating the growth of melanocytes, extracts of various cultured cell types were tested. Factors produced by melanoma and astrocytoma cell lines support continued proliferation of melanocytes in the absence of TPA. WI-38, a fibroblast cell line derived from human embryonic lung, was the most active source of melanocyte growth factors. No melanocyte growth-promoting activity was found in extracts of cultured neuroblastoma, renal cancer, normal keratinocytes, or renal epithelium. Nerve growth factor, epidermal growth factor, melanocyte-stimulating hormone, transforming growth factor-beta, and platelet-derived growth factor did not have growth-promoting activity for melanocytes. The presence of melanocyte growth factors and TPA together resulted in the strongest mitogenic activity for melanocytes, permitting the recovery (at 20 days) of 4 to 20 times as many cells as in growth factor or TPA alone.     

Site-specific integration of H-ras in transformed rat embryo cells

A karyotypic analysis was performed on seven independently derived clones of primary rat embryo cells transformed by the ras oncogene plus the cooperating oncogene myc. The transfected oncogenes were sometimes present in amplified copy number, with heterogeneity in the levels of amplification. Some chromosomal features, such as aberrantly banding regions and double-minute chromosomes, typical of cells carrying amplified genes, were also seen in three of the seven cell lines. Underlying this heterogeneity there was an unexpected finding. All seven lines showed a common integration site for ras on the q arm of rat chromosome 3 (3q12), though some lines also had other sites of integration. In four of the lines integration of ras was accompanied by deletion of the p arm of chromosome 3 or its possible translocation to chromosome 12.     

p53: a frequent target for genetic abnormalities in lung cancer

Allele loss is a hallmark of chromosome regions harboring recessive oncogenes. Lung cancer frequently demonstrates loss of heterozygosity on 17p. Recent evidence suggests that the p53 gene located on 17p13 has many features of such an antioncogene. The p53 gene was frequently mutated or inactivated in all types of human lung cancer. The genetic abnormalities of p53 include gross changes such as homozygous deletions and abnormally sized messenger RNAs along with a variety of point or small mutations, which map to the p53 open reading frame and change amino acid sequence in a region highly conserved between mouse and man. In addition, very low or absent expression of p53 messenger RNA in lung cancer cell lines compared to normal lung was seen. These findings, coupled with the previous demonstration of 17p allele loss in lung cancer, strongly implicate p53 as an anti-oncogene whose disruption is involved in the pathogenesis of human lung cancer.     

EGFR mutations in lung cancer: correlation with clinical response to gefitinib therapy

Receptor tyrosine kinase genes were sequenced in non-small cell lung cancer (NSCLC) and matched normal tissue. Somatic mutations of the epidermal growth factor receptor gene EGFR were found in 15of 58 unselected tumors from Japan and 1 of 61 from the United States. Treatment with the EGFR kinase inhibitor gefitinib (Iressa) causes tumor regression in some patients with NSCLC, more frequently in Japan. EGFR mutations were found in additional lung cancer samples from U.S. patients who responded to gefitinib therapy and in a lung adenocarcinoma cell line that was hypersensitive to growth inhibition by gefitinib, but not in gefitinib-insensitive tumors or cell lines. These results suggest that EGFR mutations may predict sensitivity to gefitinib.     

Direct interaction of a ligand for the erbB2 oncogene product with the EGF receptor and p185erbB2

The erbB2 oncogene encodes a 185-kilodalton transmembrane protein whose sequence is similar to the epidermal growth factor receptor (EGFR). A 30-kilodalton factor (gp30) secreted from MDA-MB-231 human breast cancer cells was shown to be a ligand for p185erbB2. An antibody to EGFR abolished the tyrosine phosphorylation induced by EGF and transforming growth factor-alpha (TGF-alpha) but only partially blocked that produced by gp30 in SK-BR-3 breast cancer cells. In two cell lines that overexpress erbB2 but do not expresss EGFR (MDA-MB-453 breast cancer cells and a Chinese hamster ovary cell line that had been transfected with erbB2), phosphorylation of p185erbB2 was induced only by gp30. The gp30 specifically inhibited the growth of cells that overexpressed p185erbB2. An antibody to EGFR had no effect on the inhibition of SK-BR-3 cell colony formation obtained with gp30. Thus, it appeared that gp30 interacted directly with the EGFR and erbB2. Direct binding of gp30 to p185erbB2 was confirmed by binding competition experiments, where gp30 was found to displace the p185erbB2 binding of a specific antibody to p185erbB2. The evidence described here suggests that gp30 is a ligand for p185erbB2.     

促肝细胞再生磷酸酶-3蛋白在5株癌细胞中的表达

目的研究促肝细胞再生磷酸酶-3(phosphatase of regenerating liver-3,PRL-3)在5株癌细胞(HO-8910PM、CNE-2Z、A549、JAR和BEL-7402)中的表达情况,为选择合适的细胞株克隆PRL-3基因奠定基础。方法用Western blot分析PRL-3在5株癌细胞(HO-8910PM、CNE-2Z、A549、JAR和BEL-7402)中的表达。结果PRL-3蛋白在5株癌细胞中都有表达:在HO-8910PM与CNE-2Z中呈高度表达,在A549和BEL-7402中呈中等程度表达,而在JAR中呈低度表达。结论PRL-3在5株癌细胞中均有表达,可选择高表达的HO-8910PM或CNE-2Z细胞克隆PRL-3基因。     

Synthesis and anticancer activity of (+)-nopinone-based 2-amino-3-cyanopyridines

Twelve (+)-nopinone-based 2-amino-3-cyanopyridines 4a–l were synthesized from (–)-β-pinene. The structures of these compounds were characterized by FT-IR, ¹H NMR, and ESI-MS. All the compounds were tested for their anticancer activity against lung cancer cell line A549, gastric cancer cell line MKN45 and breast cancer cell line MCF7 by MTT method, respectively. The results showed that compounds 4f, 4j and 4k had promising anticancer activity against these cancer cell lines, in particular, compound 4f exhibited broad-spectrum and highly efficient anticancer activity against cell lines A549, MKN45 and MCF7 with IC₅₀ of 23.78, 67.61 and 53.87 µmol·L⁻¹, respectively. The preliminary analysis of the structure activity relationship implied that the Br or Cl substituted group of the benzene ring in these derivatives significantly contributed to the anticancer activity.     

红松种鳞多酚抗肿瘤作用的研究

[目的]研究红松种鳞多酚对癌细胞体外增殖的抑制作用.[方法]分别采用不同浓度红松多酚提取液对人骨髓神经母细胞瘤细胞株SH-SY5Y、人肺腺癌细胞株A549、人皮肤癌细胞株A375、人肝癌细胞株HepG2、人卵巢癌细胞株SKOV3这5种常见的肿瘤细胞进行试验,采用MTT法检测体外细胞增殖抑制率.[结果]红松多酚提取物对SH-SY5Y、HepG2、SKOV3的抑制作用不明显,而对A549、A375均有抑制效果.[结论]在红松多酚提取液固形物含量为0.4 mg/ml时,其对A549细胞抑制效果最佳,在该浓度下,红松多酚提取液对人肺腺癌细胞A549的抑制率可达到55％.     

Lymphokine production by cultured human T cells transformed by human T-cell leukemia-lymphoma virus-I

Cell-free conditioned media from human T cells transformed by human T-cell leukemia-lymphoma virus (HTLV-I) were tested for the production of soluble biologically active factors, including several known lymphokines. The cell lines used were established from patients with T-cell leukemia-lymphoma and from human umbilical cord blood and bone marrow leukocytes transformed by HTLV-I in vitro. All of the cell lines liberated constitutively one or more of the 12 biological activities assayed. These included macrophage migration inhibitory factor (MIF), leukocyte migration inhibitory factor (LIF), leukocyte migration enhancing factor (MEF), macrophage activating factor (MAF), differentiation inducing factor (DIF), colony stimulating factor (CSF), eosinophil growth and maturation activity (eos. GMA), fibroblast activating factor (FAF), gamma-interferon and, in rare instances, T-cell growth factor (TCGF). Some cell lines produced interleukin 3 (IL-3), platelet-derived growth factor (PDGF), or B-cell growth factors (BCGF). Such cells should prove useful for the production of lymphokines and as sources of specific messenger RNA's for their genetic cloning.     

GPC3在肝癌患者血清、癌组织和肝癌细胞株中的表达

目的探讨GPC3在肝癌患者血清、组织和肝癌细胞株中的表达。方法荧光定量PCR检测GPC3基因在HepG2、Huh7、LM3肝癌细胞株及HL7702正常肝细胞株中的表达;免疫组化S-P法检测肝癌患者癌组织、癌旁组织及良性病变中Glypican-3蛋白的表达;Western blot检测肝癌、慢性肝炎患者和正常人血清中Glypican-3蛋白的表达。结果 GPC3基因在肝癌细胞系HepG2、Huh7、LM3中的表达分别为35.38、11.82、35.77,在正常肝细胞系HL7702中不表达;Glypican-3蛋白在肝癌组织、癌旁组织及良性病变中的表达率分别为72.9%、0%、0%;肝癌、慢性肝炎患者和正常人血清中Glypican-3蛋白阳性率分别为51.6%、0%、0%。结论 GPC3在肝癌患者血清、组织和肝癌细胞株中均呈高表达。     

Malignant activation of a K-ras oncogene in lung carcinoma but not in normal tissue of the same patient

A single genetic alteration, a guanine-to-cytosine transversion, is responsible for the acquisition of malignant properties by K-ras genes of two human tumor cell lines established from carcinomas of the bladder (A1698) and lung (A2182). As a consequence, arginine instead of the normal glycine is incorporated into the K-ras-coded p21 proteins at amino acid position 12. This mutation creates a restriction enzyme polymorphism that can be used to screen human cells for transforming K-ras genes. This approach was used to identify the mutational event responsible for the malignant activation of a K-ras oncogene in a squamous cell lung carcinoma of a 66-year-old man; this point mutation was not present in either the normal bronchial or parenchymal tissue or in the blood lymphocytes. Hence, malignant activation of a ras oncogene appears to be specifically associated with the development of a human neoplasm.     

Deleted HTLV-I provirus in blood and cutaneous lesions of patients with mycosis fungoides.

Mycosis fungoides, a rare form of cutaneous T cell leukemia/lymphoma, is suspected of having a viral etiology on the basis of certain similarities to adult T cell leukemia, which is associated with human T cell leukemia/lymphoma virus type I (HTLV-I) infection. Cell lines were established from peripheral blood mononuclear cells (PBMC) of an HTLV-I-seronegative patient with mycosis fungoides. DNA hybridization analysis revealed the presence of HTLV-I-related sequences with unusual restriction endonuclease sites. Sequence analysis of subcloned fragments demonstrated the presence of a monoclonally integrated provirus with a 5.5-kilobase deletion involving large regions of gag and env and all of pol. Additional evidence for the presence of deleted proviruses was found by polymerase chain reaction (PCR) amplification of DNA from cutaneous lesions of five other HTLV-I-seronegative patients. The findings suggest that HTLV-I infection may be involved in the etiology of at least certain cases of mycosis fungoides.     

Normal cells of patients with high cancer risk syndromes lack transforming activity in the NIH/3T3 transfection assay

Oncogenes capable of transforming NIH/3T3 cells are often present in human tumors and tumor cell lines. Such oncogenes were not detected in normal fibroblast lines derived from patients with several clinical syndromes associated with greatly increased cancer risk. Thus, germ-line transmission of these oncogenes does not appear to be the predisposing factor responsible for these high cancer risk syndromes.     

喙尾琵琶甲提取物的体外抗肿瘤活性研究

[目的]观察喙尾琵琶甲提取物对体外培养人肿瘤细胞株的生长抑制作用。[方法]喙尾琵琶甲粗提物,通过硅胶柱层析分离得不同极性部分,运用MTT法观察不同部分对人白血病细胞株K562和HL-60、人肺癌细胞株A549的生长抑制情况。[结果]粗提物、石油醚和氯仿部分三者最高浓度(300μg/ml)对K562、HL-60、A549的生长抑制率均>69%,半数抑制浓度(IC50)均<100μg/ml。[结论]喙尾琵琶甲粗提物、石油醚和氯仿部分对K562、HL-60、A549的生长具有很好的抑制作用。     

Bovine leukemia virus long terminal repeat: a cell type-specific promoter

The functional activity of the promoter unit contained within the long terminal repeat (LTR) of bovine leukemia virus (BLV) was examined by monitoring transient expression of a heterologous gene placed under its control. Various cell lines were transfected with recombinant plasmids carrying the bacterial chloramphenicol acetyltransferase (CAT) gene coupled to the BLV LTR (pBL-cat). Transient expression of CAT activity directed by the BLV LTR was observed only in the established BLV-producer cell lines derived from fetal lamb kidney (FLK) cells and bat lung cells. The amount of CAT activity transiently expressed in FLK-BLV cells was decreased approximately tenfold by deletion of LTR sequences located within a region 100 to 170 nucleotides upstream of the RNA start site. Surprisingly, removal of the region 50 base pairs downstream of the RNA initiation site to the 3'-end of the LTR reduced the expression of CAT activity by 87 percent. The BLV LTR thus appears to be an unusual promoter unit, functioning in a cell type-specific manner and possessing sequences on both the 5' and 3' sides of the RNA start site that influence gene expression.     

血浆miR-200c作为肺癌早期诊断的临床价值研究

目的 分析血浆miR-200c的表达与肺癌患者临床病理特征的相关性,并探讨miR-200c能否作为肺癌早期诊断的潜在肿瘤标志物的可能性。方法 收集55例肺癌患者和53例健康体检者,采用实时荧光定量PCR检测受检者血浆miR-200c的表达情况,对检测结果进行统计学分析。结果 miR-200c在肺癌患者组血浆中表达水平均高于正常对照组,差异有统计学意义（P<0.01）。受试者工作特征曲线显示miR-200c能够将肺癌与正常对照组区分出来（AUC=0.676）。结论 血浆miR-200c的表达可能与肺癌的发生有关,提示miR-200c可作为特异性生物标志物对肺癌患者进行早期诊断的可能性。