胃泌素对胃癌细胞粘着斑激酶酪氨酸磷酸化的影响

背景与目的:胃泌素能够刺激胃癌细胞的生长和增殖,这一作用同酪氨酸激酶有关。本研究旨在阐明胃泌素对人胃癌细胞内粘着斑激酶(focaladhesion kinase,FAK)酪氨酸磷酸化的影响。方法:用人胃泌素受体(gastrinreceptor,GR)的真核表达载体pCR3.1/GR,转染人胃癌细胞株SGC7901,增强胃泌素受体表达;用胃泌素受体拮抗剂L-365260,抑制胃泌素和其受体结合;以不同浓度和作用时间的胃泌素刺激胃癌细胞,利用免疫沉淀和蛋白质印迹法检测上述情况下,FAK酪氨酸磷酸化的变化。结果:分别用0.1nmol/L、1nmol/L和10nmol/L的胃泌素作用后,转染pCR3.1/GR的SGC7901细胞内FAK酪氨酸磷酸化表达量分别为0.64±0.06、0.91±0.10和1.00±0.10,高于SGC7901细胞的0.40±0.05、0.52±0.07和0.62±0.06(P<0.01);转染pCR3.1/GR的SGC7901细胞内FAK酪氨酸磷酸化表达量分别为0.72±0.08、0.83±0.05、0.88±0.06和1.00±0.08,高于SGC7901细胞的0.59±0.05、0.65±0.07、0.58±0.03和0.47±0.10(P<0.01或P<0.05)。胃泌素受体拮抗剂L-365260使转染pCR3.1/GR的SGC7901细胞内FAK酪氨酸磷酸化表达量从1.00±0.07降至0.72±0.07(P<0.01),使SGC7901细胞内表达量由0.62±0.06降至0.45±0.05(P<0.01)。在此过程中,FAK蛋白表达量差异无统计学意义(P>0.05)。结论:FAK是胃泌素和其受体结合后发挥效应的关键下游信号分子,酪氨酸磷酸化是其活性形式。     

人胃癌SGC-7901细胞胞浆胞核性激素受体测定

 作者采用葡聚糖包被活性碳饱和分析法(DCC法)分别测定了培养的人胃低分化腺癌SGC-7901细胞的胞浆及胞核KCL抽提液中的雌激素受体(ER)、孕激素受体(PR)和雄激素受体(AR)的含量。 结果证明胃癌SGC-7901细胞的胞浆及胞核抽提液中ER含量为30.2和35.7fmol/mg蛋白，而PR的含量为20.3和22.7fmol/ng蛋白, 但AR均为阴性(<10fmol/mg蛋白), 这说明SGC-7901细胞为ER及PR阳性细胞, 其ER和PR在胞浆、胞核中均有分布。 提示胃癌可能为性激素依赖性肿瘤, 有内分泌治疗的可能。     

结直肠癌雌激素受体及孕激素受体的定量研究

背景与目的许多研究表明结直肠癌与雌激素相关,结直肠癌组织中表达雌激素受体(estrogenreceptor,ER)、孕激素受体(progesteronereceptor,PR),但多采用免疫组化方法检测,且结果不一,而ER.PR的定量研究不多。本研究拟定量测定结直肠癌组织及正常组织的ER,PR表达水平,并探讨它们之间的关系及与结直肠癌患者临床病理参数的关系。方法应用受体放射配基结合分析法(radioligandbindingassay,RBA)定量测定45例结直肠癌组织及结直肠正常组织的胞浆及胞核ER、PR的水平。结果45例标本结直肠正常组织及癌组织都表达ER、PR,胞浆ER表达癌组织高于正常组织,分别为7.96±3.69fmol/mgprotein和4.34±2.84fmol/mgprotein,(P<0.01);胞浆PR表达癌组织高于正常组织,分别为3.89±2.64fmol/mgprotein和2.50±1.73fmol/mgprotein,(P<0.01);胞核ER表达癌组织高于正常组织,分别为18.42±8.30fmol/mgprotein和11.24±5.44fmol/mgprotein,(P<0.01);胞核PR表达癌组织高于正常组织,分别为9.36±5.90fmol/mgprotein和7.84±7.41fmol/mgprotein,(P<0.05)。癌组织胞浆及胞核的ER表达与PR表达呈正相关,(P<0.01);正常结直肠组织胞浆ER表达与PR表达呈正相关,(P<0.01),而胞核内两者不相关,(P>0.05)。结直肠癌组织ER表达与患者年龄相关,大于45     

激素难治性前列腺癌组织中雄激素受体蛋白表达的研究

背景与目的:近来有研究报道,在激素难治性前列腺癌(hormonerefractoryprostatecarcinoma,HRPC)中发现有雄激素受体(androgenreceptor,AR)基因扩增,并提出AR基因扩增可能是导致激素治疗失败的一个新的分子机制。本研究拟对前列腺癌在激素治疗前和治疗失败后的AR蛋白表达作定量测定,进一步探讨AR表达与HRPC发生的关系。方法:采用放射配体结合分析方法测定28例晚期前列腺癌患者在激素治疗前以及治疗失败后原发癌组织中的AR蛋白含量。结果:28例前列腺癌在治疗前、后癌组织中的AR蛋白平均水平分别为(390.0±204.1)和(690.4±444.0)fmol/mgProtein,两者间差异有显著性(P<0.001)。其中10例在治疗后12个月内复发,其AR蛋白平均水平在治疗前、后分别为(398.2±199.5)和(448.2±274.1)fmol/mgProtein两者间差异无显著性(P>0.20),其余18例的AR蛋白平均水平在治疗前、后分别为(386.4±212.3)和(824.9±468.6)fmol/mgProtein,两者间差异有显著性(P<0.001)。结论:AR蛋白水平升高可能是前列腺癌对激素治疗不敏感的原因之一。     

胞核雄激素受体测定对评价前列腺癌、肝癌受体状态的意义

背景与目的:雄激素受体(androgenreceptor,AR)与前列腺癌(prostatecarcinoma,PC)、原发性肝癌(hepatocellularcacinoma,HCC)的发生、发展有关,对临床治疗方案选择及预后的评估等有一定影响,准确判断肿瘤组织的AR状态有重要的临床意义。本研究旨在通过对胞核雄激素受体(nuclearAR,AnR)进行分析,探讨AnR对评估前列腺癌、原发性肝癌雄激素受体状态的意义。方法:取94例PC和192例HCC患者的肿瘤组织及癌周组织,采用受体放射配基结合分析法(radioligandbindingassay,RBA)对组织中胞浆雄激素受体(cytosolAR,AcR)、胞核雄激素受体的亲和力(affinity,KD)、最大结合容量(maximumconcentrationofreceptor,Bmax)进行分析。结果:PC患者中肿瘤组织AcR、AnR的Bmax值(58.82±34.73)、(543.70±249.44)fmol/mgprotein明显高于癌周组织的(21.63±14.89)、(89.20±47.32)fmol/mgprotein(P<0.001);其KD值(0.84±0.52)、(2.15±0.79)nmol/L与癌周组织的(0.78±0.49)、(2.24±0.84)nmol/L之间的差异无统计学意义(P>0.50)。HCC患者中,肿瘤组织AcR、AnR的Bmax值(18.09±16.87)、(59.93±34.12)fmol/mgprotein亦明显高于癌周组织的(10.87±7.60)、(25.54±20.10)fmol/mgprotein(P<0.001);其KD值(0.76±0.57)、(1.89±0.74)nmol/L与     

外源性胃泌素对胃癌细胞凋亡和凋亡调控基因bcl-2的影响

背景与目的:大量研究表明,外源性胃泌素对胃癌、结肠癌等胃肠道肿瘤细胞有促生长作用,但胃泌素是否参与了细胞的凋亡调控尚未见报道。本文旨在探讨胃泌素在胃癌细胞凋亡调控中的作用。方法:应用流式细胞仪观察胃泌素及其受体拮抗剂丙谷胺对MKN45胃癌细胞凋亡的影响;ABC免疫组化法测定细胞bcl-2基因的表达。结果:细胞培养48h后,胃泌素组细胞凋亡百分率为(1.39±0.54)%,明显低于对照组的(8.58±0.67)%(P<0.01);胃泌素组bcl-2基因阳性率为(22.3±5.3)%,明显高于对照组的(12.2±1.8)%(P<0.01),且随着时间延长表达率进一步增加。联合应用丙谷胺后上述作用消失。结论:胃泌素可能通过诱导细胞bcl-2基因的表达而抑制细胞的凋亡,丙谷胺可阻断胃泌素的凋亡调控作用。     

肝细胞癌患者外周血性激素受体和糖皮质激素受体的含量

为探讨性激素受体(Sex Hormone Receptor)和糖皮质激素受体(Glucocorticoid Receptor.GR)与肝细胞癌(Hepa- tocelular carcinoma.HCC)的关系及其意义,应用放射配体测定13例HCC患者及23例正常人外周血淋巴细胞雌激素受体(Es- trogen Receptor.ER)和雄激素受体(Androgen Receptor.AR)及外周血细胞GR水平.正常人ER和AR分别为616±106和687±109位点/细胞;GR为5360±1684位点/细胞.HCC患者ER和AR分别为968±120和2903±860位点/细胞.HCC伴肝硬化GR为3112±1130位点/细胞、不伴肝硬化为4536±1201位点/细胞.AR水平明显高于对照组,提示HCC可能为雄激素依赖性肿瘤;GR水平与肝硬化负相关,提示GR下降反映肝硬化的程度.     

大肠癌组织胃泌素与增殖细胞核抗原表达的关系

目的 :研究大肠癌组织胃泌素与增殖细胞核抗原 (proliferatingcellnuclearantigen ,PCNA)表达的关系 ,以探讨胃泌素对大肠癌的促增殖作用。方法 :采用免疫组化法检测 4 8例大肠癌患者癌组织及癌旁粘膜胃泌素和PCNA的表达。结果 :大肠癌组织胃泌素阳性率为 3 9 5 % ,高分化腺癌明显高于低分化和粘液腺癌 (P <0 0 5 )。癌组织的PCNA LⅠ显著高于癌旁粘膜和正常粘膜 (P <0 0 1) ,Dukes C期和D期显著高于A期 (P <0 0 5 )。胃泌素阳性组癌组织PCNA LⅠ为 63 16± 15 14 ,胃泌素阴性组为 4 7 4 1± 13 0 4 ,两者差异显著 (P <0 0 1)。结论 :部分大肠癌细胞可能通过自分泌方式产生胃泌素 ,促进细胞的增殖     

癌前病变Caspase-3表达下调与胃黏膜癌变的关联

目的观察Caspase-3蛋白在胃癌及其癌前病变组织中的表达,分析它与细胞凋亡和细胞增殖的关系,探讨Caspase-3蛋白在胃癌发生过程中的生物学意义及相关分子病理学机制。方法选取184例胃黏膜活检和手术切除组织标本,其中胃癌20例,慢性萎缩性胃炎6例,萎缩性胃炎伴肠上皮化生(简称肠上皮化生)31例,萎缩性胃炎伴不典型增生(简称不典型增生)114例;正常对照13 例。采用SABC法检测Caspase-3蛋白的表达;通过图像域值分析计算其阳性指数,分析其与细胞增殖(Ki67蛋白阳性指数)和凋亡(TUNEL指数)的相关关系。结果 Caspase-3蛋白在重度不典型增生组织中的阳性指数(29．8％±3．9％)显著低于轻度(58．3％±4．2％)和中度不典型增生(50．4％± 4．8％)及萎缩性胃炎(68．3％±3．3％)或肠上皮化生(70．9％±4．3％),差异有统计学意义(P<0．05); 而与胃癌(26．9％±3．0％)相比,差异无统计学意义(P>0．05)。Caspase-3蛋白表达与细胞凋亡呈显著正相关(r=0．94,P<0．05),Caspase-3蛋白阳性组细胞增殖指数(18．3％±2．2％)显著低于阴性组(48．9％±3．1％;P<0．05)。结论 Caspase-3蛋白在萎缩性胃炎、肠上皮化生和(或)轻中度不典型增生黏膜中表达上调,而在重度不典型增生及胃癌组织中表达下调,且这种变化与细胞凋亡呈显著正相关。Caspase-3失活或表达下调相关的细胞凋亡和增殖紊乱可能在胃黏膜损伤及癌变过程中起某种作用。     

胃癌组织Skp2表达的意义及与p27表达的关系

目的探讨人胃癌S期激酶相关蛋白2(S-phase k inase-assoc iated prote in 2,Skp2)表达的意义及与p27表达的关系。方法采用免疫组化方法检测138例原发性胃癌,配对癌旁胃黏膜,102例配对淋巴结转移胃癌组织,30例非典型增生,30例肠上皮化生(肠化),10例慢性浅表性胃炎和5例正常胃黏膜Skp2的表达及138例原发性胃癌p27的表达。结果Skp2表达的阳性率(%),肠化(12.68±0.86)及癌旁胃黏膜(19.32±1.22)均明显高于慢性浅表性胃炎(0.53±0.13)及正常胃黏膜(0.47±0.19)(P=0.000),后两者差异无显著性(P=0.716);非典型增生(16.74±0.82)明显高于肠化(P=0.000);原发性胃癌(31.34±2.17)明显高于非典型增生及癌旁胃黏膜(P值均=0.000);淋巴结转移胃癌组织(39.76±2.00)明显高于原发性胃癌(P=0.037)。胃癌Skp2的阳性率与分化程度(rho=0.315,P=0.000)、脉管内瘤栓(rho=0.303,P=0.000)及淋巴结转移(rho=0.254,P=0.000)呈正相关。胃癌Skp2表达与靶蛋白p27表达呈负相关(rho=-0.451,P=0.000)。结论Skp2蛋白过表达与胃癌的发生及转移有关;胃癌Skp2蛋白过表达与p27蛋白降解有关,提示Skp2蛋白过表达在胃癌发生、发展过程中可能起重要作用。     

Clinical significance of gastrin receptors in human colon cancers

We have measured gastrin receptors (GR) in surgical specimens from 67 patients with primary colon cancers in order to determine the clinical significance of GR in colon cancer. GR analysis was performed on these specimens, and 22 cancers (32.8%) had no detectable GR. Thirty-eight cancers (56.7%) had high-affinity (Kd less than 1.0 nM) levels of GR. Seven cancers (10.4%) had only low-affinity GR (Kd greater than 1.0 nM). Twenty patients (29.9%) had cancers with GR greater than 10 fmol/mg protein. Mean GR content was significantly greater (11.8 +/- 2.9 fmol/mg protein) in Dukes' Stage A and B cancers when compared to Stage C and D cancers (6.2 +/- 1.6 fmol/mg protein). A significantly greater percentage (52.4%) of patients in the early stages (A and B) had tumors with greater than 10 fmol/mg protein compared to patients with more advanced (C and D) cancers (19.6%). GR content did not correlate with histological differentiation, patient age, or preoperative carcinoembryonic antigen levels. No difference in the GR content was noted between left and right colon cancers or in patients of different sex or race. GR content of normal colon mucosa correlated with the GR content of colon cancers from the same surgical specimen, suggesting that these tumors maintain their normal complement of GR. In the early period of follow-up, 12 of 43 (28%) Stage C and D patients with GR less than 10 fmol/mg protein have died, whereas all 8 Stage C and D patients with GR greater than 10 fmol/mg protein are alive. GR content of colon cancers may have prognostic significance and may identify a group of patients with colon cancer that may benefit from hormonal therapy with antigastrin drugs.     

Content of glucocorticoid receptor and arginase in gastric cancer and normal gastric mucosal tissues

The content of glucocorticoid receptor (GR) and arginase in human gastric cancer and the corresponding normal gastric mucosal tissues was determined. Among the 25 patients studied, the GR content in gastric cancer tissues was 33.2 +/- 10.2 fmol/mg protein versus 7.6 +/- 3.4 fmol/mg protein in gastric mucosal tissues. This difference is statistically significant (P less than 0.005). Of the 25 paired samples, 19 cancer tissues contained GR, whereas only seven of the normal mucosal tissues had GR. The level of arginase in gastric cancer tissues in 19 patients was assayed, it was 26.6 +/- 4.2 ng/mg protein which is also significantly higher than that in normal gastric mucosal tissues (13.5 +/- 1.8 ng/mg protein) (P less than 0.005). Since glucocorticoids and arginase are potent immune suppressive agents, the increased level of GR and arginase in gastric cancer tissue suggest that these glucocorticoid-related factors in gastric cancer tissue may play a partial role in regulating cellular immunity.     

Sex hormone receptors in gastric cancer

Gastric adenocarcinoma that originates from mucosal tissue invades submucosa, muscle, and serosa in different stages. The level of progesterone receptors (PgR), estrogen receptors (ER), and androgen receptors (AdR) in the superficial part of gastric cancer tissues (CAs) from 16 patients was determined and compared with that of the corresponding normal gastric mucosal tissues (NLm). There were PgR in all CAs (100%) with values that ranged from 20.5 to 548.4 fmol/mg protein. Eight CAs (50%) had ER values that ranged from 6.8 to 325.1 fmol/mg protein. AdR was found in two CAs with values of 14.7 and 16.4 fmol/mg protein. In NLm, 15 (93.8%) had PgR values that ranged from 7.3 to 473.2 fmol/mg protein and ten (62.5%) had ER values that ranged from 0.9 to 87.9 fmol/mg protein. AdR were present in two NLm with values of 1.5 and 73.5 fmol/mg protein. There was no statistical difference in levels of PgR and ER between CAs and NLm. There were PgR in all gastric cancers and in 93.8% of NLm. The results suggest that gastric mucosa may be the target tissues for progesterone action. Furthermore, the lack of correlation between the levels of ER and PgR in gastric cancer tissue suggests that the PgR in gastric cancers are probably estrogen independent.     

EGFR in colorectal cancer: more than a simple receptor.

BACKGROUND: Advances in the understanding of tumor biology have led to the development of targeted therapies allowing progress in colorectal cancer treatment. One of the most promising targets is the epidermal growth factor receptor (EGFR). METHOD: The presence and distribution of high- and low-affinity EGFR was investigated retrospectively in a group of 82 colorectal cancer samples (43 normal colon-colon cancer paired samples) using a specific ligand binding assay (Scatchard Analysis). FINDINGS: A large majority of tumor samples exhibited one class of high-affinity binding sites (78%). Eighteen cases (22%) exhibited both high- and low-affinity binding sites. A wide interpatient variability was observed for the site number, with physiologically-relevant high-affinity sites ranging from 7 to 310 fmol/mg protein in tumors and from 6 to 313 fmol/mg protein in normal mucosa. A significant positive correlation was demonstrated between tumor and normal mucosa for the high-affinity Kd values and for the number of high-affinity sites, suggesting a common regulation for both tumor and normal tissue. INTERPRETATION: These observations (i) could explain recently-reported clinically-active EGFR targeting in colorectal tumors apparently negative for EGFR, and (ii) may offer a plausible explanation for the link observed between toxicity in normal tissue (cutaneous rash) and clinical outcome of patients treated with anti-EGFR drugs. Present data extends our understanding of EGFR identity in colorectal cancer which could be useful in reconsidering the predictive tools for the identification of tumors putatively responsive to EGFR targeted therapy.     

Decrease of prostaglandin I2 binding sites in thyroid cancer

The properties of specific prostaglandin I2 (prostacyclin, PGI2) binding sites in normal thyroid tissue have been characterised. Tissue samples obtained intraoperatively from patients with 'cold' solitary thyroid nodules (as preoperatively selected by thyroid gland scintigraphy, thyroid gland ultrasonography and Papanicolaou cytology following fine needle aspiration of the nodule area) have been used for thyroid membrane preparation. Employing [3H]iloprost, a chemically stable PGI2-analogue as a radioligand, saturation experiments for comparative binding studies have been attempted. Scatchard analysis of the binding data obtained for normal thyroid parenchyma distant to the nodule area revealed heterogeneity of the [3H]iloprost sites exhibiting a high-affinity binding capacity (Bmax) of 613.2 +/- 130.4 fmol mg-1 membrane protein and a low-affinity binding capacity of 5.1 +/- 1.6 pmol mg-1 membrane protein. The equilibrium dissociation constant (Kd) amounted to 18.9 +/- 8.9 nM and to 131.5 +/- 39.2 nM, respectively. Scatchard analysis of the binding data obtained for benign thyroid adenoma indicated significant lower binding capacities exhibiting a Bmax of 325.8 +/- 110.0 fmol mg-1 membrane protein (Kd: 31.0 +/- 7.5 nM) for the high-affinity sites and of 3.9 +/- 2.5 pmol mg-1 membrane protein (Kd: 364.9 +/- 183.6) for the low affinity sites. In cancer tissue a selective loss of the low affinity sites and a significant diminution of the high-affinity sites was observed: in well differentiated cancer the high-affinity sites showed a Bmax of 299.7 +/- 46.0 fmol mg-1 membrane protein (Kd: 38.9 +/- 7.3 nM), in anaplastic cancer, less differentiated papillar and follicular cancers of 180.6 +/- 25.1 fmol mg-1 membrane protein (Kd: 54.6 +/- 16.7 nM). Well differentiated papillar and follicular cancers did not differ from each other.(ABSTRACT TRUNCATED AT 250 WORDS)     

Quantitative assays of epidermal growth factor receptor in human breast cancer: cut-off points of clinical relevance

Epidermal growth factor receptor (EGFr) assays were performed by 3 different methods on 246 human primary breast carcinomas. Scatchard analyses of multipoint binding data on 19 of the first 209 tumours, performed by a displacement method, demonstrated that the majority of tumours exhibited 2 classes of binding site, the high-affinity site with an affinity constant (KD) of mean 2 nmol/l (SD 1.3, range 0.44-7 nmol/l), and a low-affinity site, KD mean 9.5 nmol/l (range 6-15.5 nmol/l). Scatchard analysis of multipoint assays using increasing concentrations of 125I-labelled EGF showed that saturation of the high-affinity site occurred in the majority of saturation of the high-affinity site occurred in the majority of tumours at a concentration of labelled EGF of I nM. Comparison of the KD values of the high-affinity site obtained from displacement assays with those obtained by increasing labelled EGF showed that the KD was significantly higher (p = 0.0002) when measured by the latter method. There was no difference in binding capacity of the high-affinity or low-affinity sites by the 2 methods. A 2-point assay with I nM labelled EGF (specific activity approx. 80-130 microCi/microgram) correlated with quantitative values for the high-affinity site from Scatchard analysis (p less than 0.02). There was a strong inverse relationship between EGFr greater than 10 fmol/mg membrane protein (2-point assay) and ER (dextran-coated charcoal method), Chi-squared 2 X 2 contingency table test = 34.027, p less than 0.0001. Follow-up data from 135 patients revealed a strong inverse relationship between EGFr greater than 10 fmol/mg membrane protein and oestrogen receptor (ER) status and a positive correlation with early recurrence and death. Our data describe a reproducible assay for EGFr and show that a cut-off point at 10 fmol/mg allows clinically useful application.     

Comparison of steroid receptor levels in renal-cell carcinoma and autologous normal kidney

Since a number of renal-cell carcinomas regress with hormonal manipulation, we have identified and measured the levels of estrogen, progestin and glucocorticoid receptors in 47 autologous pairs of normal and neoplastic kidney tissues. High-affinity receptors for these hormones were detected in kidney tissues of both sexes by means of a dextran-coated charcoal assay. Glucocorticoid receptors were demonstrated in renal cancer tissues for the first time, and were higher in the tumor (mean 31.3 ± sem 5.6) than in the normal tissue (mean 18.5 ± sem 3.1 fmol/mg cytosol protein). There was a significant difference in the quantities of progestin receptors (expressed as fmol/mg cytosol protein) in normal (mean 18.4 ± sem 3.3) versus neoplastic (mean 10.4 ± sem 4.0) kidney specimens (p < 0.007). There was a significant difference between the binding affinity of the progestin receptor in the male tumors (Kd = 2.2 ± sem 0.9 nM, n = 10) and that of the females, (Kd = 9.3 ± sem 6.5 nM) (p < 0.04). When an affinity of < 9.9 × I0^?9M and > 10 fmol/mg cytosol protein were used as criteria for classifying a tissue as positive for progestin receptors, only 17% of tumors contained these receptors while 45% of normal tissues exhibited them. According to these criteria, no differences were observed in the frequency of occurrence of either estrogen receptors or glucocorticoid receptors in tumor versus normal kidney. Data from this study suggest that the use of endocrine therapy should be re-examined in the treatment of renal-cell carcinoma.     

Internalization of indium-labeled LDL through a lipid chelating anchor in human pancreatic-cancer cells as a potential radiopharmaceutical for tumor localization

Low-density lipoproteins (LDL) labeled with indium via a lipid-chelating agent, the bis(stearylamide) of diethylenetriaminepentaacetic acid (L), were evaluated as a potential radiopharmaceutical (¹¹¹In-L-LDL) for tumor localization by studying their internalization in human pancreatic cancer cells (Capan-1). Using Dil-LDL (l,l′-dioctadecyl-3,3,3′,3′-tetramethylindodicarbocyanine perchlorate-LDL), this cell line was shown to bind human LDL with a high-affinity saturable component and a low-affinity non-saturable (40%) component. The single saturable high-affinity binding site had a K_D of 27.5 ± 2.1 μg/ml and a maximal binding of 610 ± 7.5 ng/ml protein. Electron-microscopic examination of the In-L-LDL particles revealed the peripheral distribution of the electron-dense indium atoms at the outer surface of LDL. The modified LDL were then shown to be internalized by the cells. After conjugation of In-L-LDL to colloidal gold to follow the different stages of internalization, electron-microscopic examination showed that the In-L-LDL gold conjugates were stuck to the external sheet of the plasma apical and microvilli membrane, into earlier and later endosomes and into multi-vesicular bodies, suggesting the penetration of the In-L-LDL particles into lysosomal vacuoles. The observation of In-L-LDL-gold conjugates in deep-seated cytoplasm suggests that LDL could be employed as a drug-transport vehicle for targeting cytotoxics or radionuclides close to the cell nucleus. Int. J. Cancer, 70:315–322, 1997. © 1997 Wiley-Liss, Inc.     

人胃癌NKM—45细胞株胞浆,胞核性激素受体含量测定及分析

作者采用葡聚糖包被活性炭法测定了人胃低分化腺癌ＮＫＭ－４５培养细胞中分离的胞浆及胞核ＫＣＩ抽提组分中的ＥＲ、ＰＲ和ＡＲ的含量。结果显示胃癌ＮＫＭ－４５细胞的胞浆及胞核抽提液中ＥＲ含量为２４．８ｆｍｏｌ／ｍｇ和２５．１ｆｍｏｌ／ｍｇ蛋白，而ＰＲ含量为１６．４ｆｍｏｌ／ｍｇ和１８．６ｆｍｏｌ／ｍｇ蛋白，ＡＲ均为阴性（＜１０ｆｍｏｌ／ｍｇ蛋白），说明ＮＫＭ－４５细胞为ＥＲ及ＰＲ阳性细胞，且ＥＲ和ＰＲ在该胃癌细胞的胞浆、胞核中均存在。作者认为胃癌可能是性激素依赖性肿瘤，适当的内分泌治疗可能对胃癌有效。