鼻咽癌患者外周血单个核细胞中P-gp和LRP的表达及其临床意义

目的通过检测鼻咽癌患者外周血单个核细胞中P-糖蛋白(P-gp)和肺耐药相关蛋白(LRP)的表达,探讨两者在鼻咽癌多药耐药中的作用及意义.方法采用流式细胞术对54例鼻咽癌患者化疗前后外周血单个核细胞中P-gp、LRP进行检测,同期选择鼻咽部非恶性肿瘤患者10例,正常健康人10例为对照组.结果 P-gp在正常人、非恶性肿瘤及鼻咽癌初治组中的表达差异无显著性,但在复发组的表达明显高于其他组,差异有显著性.LRP在初治及复发组中的表达明显高于对照组,且化疗前后差异有显著性.P-gp和LRP的表达与年龄、性别、临床分期、病理类型、淋巴结转移无显著相关.P-gp、LRP的表达与化疗疗效密切相关.结论 P-gp、LRP的表达在鼻咽癌多药耐药的产生中具有重要意义,对临床制定化疗方案具有潜在的指导意义.     

EGFR和LRP表达与卵巢癌化疗耐药及预后的关系

背景与目的:表皮生长因子受体(epidermal growth factor receptor,EGFR)的异常表达和活化能引起肿瘤细胞化疗耐药的产生.与卵巢癌化疗后复发及预后密切相关.肺耐药蛋白(lung resistance protein,LRP)是一种主要介导铂类等化疗药物耐药的多药耐药蛋白.研究表明,LRP是预测卵巢癌化疗敏感的独立预后因素.本研究探讨EGFR和LRP表达与卵巢癌化疗耐药及预后的关系.方法:采用免疫组化PV-6000二步法,检测76例恶性卵巢肿瘤、9例卵巢交界性肿瘤、17例卵巢良性肿瘤和15例卵巢正常组织中EGFR和LRP的表达,分析EGFR和LRP表达与卵巢癌化疗疗效及患者术后生存时间的关系.结果:卵巢癌组织中EGFR和LRP的阳性率分别为73.68%和71.79%,均显著高于正常卵巢组织和良性肿瘤组织(P<0.01);EGFR高表达于Ⅲ～Ⅳ期、低分化和有腹水的卵巢癌组织中(P<0.05).EGFR和LRP阳性者近期化疗有效率分别为57.14%和53.70%,低于阴性者(P<0.05);化疗耐药型卵巢癌患者EGFR和LRP阳性率分别为92.86%和85.71%,高于化疗敏感型(P<0.05).生存分析表明,卵巢癌患者3年生存率为53.00%.EGFR、LRP阳性和近期化疗疗效无效者术后生存时间短(P<0.01).结论:EGFR和LRP可作为预测卵巢癌化疗耐药及预后的指标.     

肺耐药蛋白与肿瘤细胞多药耐药研究进展

肺耐药蛋白(LRP)是一种与肿瘤细胞多药耐药(MDR)有关的蛋白质,是人类的穹窿体主蛋白(MVP).它通过减少化疗药物在细胞核和细胞质之间的比例以及改变化疗药物在细胞质内的再分布而介导肿瘤细胞产生MDR.检测肿瘤组织中LRP的表达情况,对于部分肿瘤临床治疗的选择以及预测临床疗效具有一定参考价值.     

多药耐药相关蛋白基因在肺癌组织中的表达及意义

目的探讨多药耐药相关蛋白基因（MRP1）、肺耐药蛋白（LRP）基因和增值细胞抗原Ki-67在肺癌中的表达及相关性。方法应用免疫组织化学方法,检测110例肺癌组织和22例其他恶性肿瘤（食管癌、胃癌、膀胱癌等）组织中LRP、MRP1及Ki-67的表达情况,并以其中的23例癌旁组织作比较。结果非小细胞肺癌（NSCLC）中MRP1、LRP表达水平显著高于癌旁组织（P〈0．05）,小细胞肺癌（SCLC）与癌旁组织无显著性差异（P〉0．05）。其他恶性肿瘤组织中其表达水平显著高于癌旁组织（P〈0．05）。Ki-67在各种肿瘤组织中均呈阳性表达,与LRP、MRP,表达无相关性。结论NSCLC存在广泛的原发性多药耐药现象,耐药基因LRP、MRP。参与了肺癌多药耐药的形成,LRP的表达率最高,可作为一项独立的预警指标,耐药与肿瘤细胞增殖无明显相关性。     

白细胞介素-2逆转急性白血病细胞多药耐药的临床研究

目的：研究白细胞介素-2（IL-2）对急性白血病细胞多药耐药的逆转作用。方法：选择27例复发和难治性急性白血病，用IL-2联合化疗药物治疗，通过白血病细胞P-糖蛋白（p170)。肺耐药蛋白（LRP）含量的变化和临床缓解率进行分析。结果：IL-2联合化疗药物治疗的急性白血病患者较单用联合化疗药物患者，白血病细胞p170,LRP表达减低。临床缓解率增加。结论：IL-2对急性白血病细胞的多药耐药有逆转作用；IL-2通过下调白血病细胞P170和LRP的表达，实现对急性白血病细胞多药耐药的逆转作用。     

肺耐药蛋白与肿瘤细胞多药耐药研究进展

肺耐药蛋白(LRP)是一种与肿瘤细胞多药耐药(MDR)有关的蛋白质，是人类的穹窿体主蛋白(MVP)。它通过减少化疗药物在细胞核和细胞质之间的比例以及改变化疗药物在细胞质内的再分布而介导肿瘤细胞产生MDR。检测肿瘤组织中LRP的表达情况，对于部分肿瘤临床治疗的选择以及预测临床疗效具有一定参考价值。     

非小细胞肺癌多药耐药蛋白表达的临床意义

目的:分析非小细胞肺癌(NSCLC)中的多药耐药蛋白表达与临床分期、化疗疗效等的关系,提出临床合理化疗方式.方法:对82例非小细胞肺癌外周血淋巴细胞,通过免疫组化方法检测P170、LRP、GST-π三种多药耐药蛋白的表达,观察化疗疗效.结果:在82例非小细胞肺癌中,P170表达阳性者的化疗有效率为9.8%,P170表达阴性者的化疗有效率为30.05%;LRP表达阳性者的化疗有效率达15.6%,LBP表达阴性者的化疗有效率为42.1%,GST-π化疗有效率达13.6%,GST-π表达阴性者的化疗有效率达40.0%.化疗疗效差别有统计学意义(P<0.05).结论:多药耐药蛋白表达阳性的患者,其化疗疗效差,不宜过度化疗.     

耐药基因相关蛋白在非小细胞肺癌组织中的表达及其临床意义

背景与目的肿瘤的多药耐药是肺癌化疗失败和导致患者死亡的重要原因之一。本研究的目的是探讨P糖蛋白(Pgp)、多药耐药相关蛋白(MRP)、肺耐药蛋白(LRP)、拓扑异构酶Ⅱ(TopoⅡ)、谷胱甘肽S转移酶π(GSTπ)在肺癌中的表达及其临床意义。方法采用免疫组织化学染色链亲和素生物素过氧化物酶法(streptavidin-biotin immunoperoxidase,SP)检测98例非小细胞肺癌组织中5种耐药蛋白的表达。结果Pgp、MRP、LRP、TopoⅡ、GSTπ的阳性表达率分别为27.6%、11.2%、75.5%、50.0%和64.3%。LRP、TopoⅡ在鳞癌、腺癌、腺鳞癌间的表达有显著性差异(P<0.05)。5种耐药蛋白的表达与临床分期无明显关系(P>0.05)。47例接受化疗的非小细胞肺癌患者中,Pgp、LRP、GSTπ的表达与化疗疗效有密切关系(P<0.05)。结论肺癌的耐药由多种耐药蛋白介导,联合检测肺癌组织中耐药蛋白的表达有助于选择合理的化疗方案及判断化疗疗效。     

非霍奇金淋巴瘤多药耐药的实验研究

目的 探讨初发非霍奇金淋巴瘤(NHL)mdrl mRNA及多药耐药蛋白P糖蛋白(P-gp)、肺耐药蛋白(LRP)和多药耐药相关蛋白(MRP)的表达频率及临床意义.方法 采用逆转录多聚酶链反应(RT-PCR)半定量方法检测41例初治NHL患者淋巴结活组织中瘤细胞mdrl mRNA的表达,采用流式细胞仪免疫荧光法检测P-gP、LRP、MRP的表达,以13例反应性增生淋巴结患者作为对照组.并分析多药耐药蛋白表达与NHL临床特征的关系.结果 41例NHL患者中,11例mdrl mRNA表达阳性,8例P-gP表达阳性,7例MRP表达阳性,15例LRP表达阳性.NHL组与对照组比较,MRP阳性率差异无统计学意义(P=0.887),LRP阳性率明显增高(P=0.047).NHL患者淋巴结组织P-gP、MRP、LRP表达两两之间均不存在相关关系,P-gP表达与mdrl mRNA表达正相关(r=0.396,P=0.01).P-gP表达与临床分期、LDH水平有关(均P<0.05),而与恶性分级无关.MRP表达与临床分期、恶性分级、血清乳酸脱氢酶(LDH)水平均无关(均P>0.05),而LRP表达与三者均有关(均P<0.05).P-gP和LRP表达阳性患者的完全缓解(CR)率分别为37.5%和53.3%,低于阴性表达者(均P<0.05),化疗疗效较差,而MRP表达与化疗疗效无关.结论 P-gP、LRP可能是NHL原发耐药的主要因素,影响NHL患者的化疗疗效,而MBP与NHL原发耐药无关,不影响NHL患者的化疗疗效.     

多药耐药相关蛋白和肺耐药蛋白在胃癌组织中的表达

目的　探讨多药耐药相关蛋白 (MRP)和肺耐药蛋白 (LRP)在胃癌组织中的表达及其临床意义。方法　应用免疫组化S -P法检测 90例胃癌组织和 3 0例正常胃黏膜中MRP和LRP的表达情况。结果　 90例胃癌组织中的MRP、LRP阳性表达率分别为 92 .2 %和 93 .3 % ,均高于正常胃黏膜的阳性表达率 (P <0 .0 5 ) ,在高中分化腺癌中的阳性表达率高于低分化腺癌和黏液癌 (P <0 .0 5 ) ,不同浸润程度及是否有淋巴结转移者的阳性表达率相互比较无显著性差异 (P >0 .0 5 )。结论　MRP、LRP在胃癌组织中均呈高表达 ,均在胃癌原发性多药耐药中起重要作用     

Expression of multidrug resistance proteins,P-gp,MRP1 and LRP,in soft tissue sarcomas analysed according to their histological type and grade

The biological behaviour of different histological types and grades of soft tissue sarcomas (STS) varies. This might result in a differing sensitivity to cytotoxic drugs. Cross-resistance to functionally and structurally distinct natural-product drugs, known as multidrug resistance (MDR), is associated with the overexpression of P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1) and lung resistance-related protein (LRP). The purpose of this study was to evaluate the expression of P-gp, MRP1 and LRP in STS according to their histological type and grade. In 141 chemotherapy-naive STS patients, the expression of the three MDR proteins was detected by immunohistochemistry. Nine histological types were documented. These were 19% grade 1, 34% grade 2 and 47% grade 3 tumours. Expression of P-gp and LRP was observed more frequently than the expression of MRP1 (P<0.0001). P-gp expression was most pronounced in malignant fibrous histiocytoma (MFH), but was low in leiomyosarcomas. MRP1 was expressed in most malignant peripheral nerve sheath tumours (MPNST). LRP was strongly expressed in MFH and unspecified sarcomas, but was low in liposarcomas. MRP1 and LRP expression was significantly more common in grades 2 and 3 compared with grade 1 tumours. P-gp expression was correlated with MRP1, especially in grade 3 STS. In conclusion, P-gp, MRP1 and LRP are expressed in the majority of STS, but this expression varies according to the histological type. MRP1 and LRP, but not P-gp expression, were found to be correlated to tumour grade. MDR might contribute to the observed differences in clinical behaviour within the heterogeneous group of STS.     

Multidrug resistance protein expression of adult T-cell leukemia/lymphoma

In adult T-cell leukemia/lymphoma (ATL), it is difficult to achieve remission and the reason for the resistance to chemotherapeutic agents may be linked to the presence of multidrug resistance (MDR) proteins. Lung resistance-related protein (LRP), multidrug resistance-associated protein and P-glycoprotein are three MDR proteins which we examined in ATL cells using multiparametric flow cytometry and real-time RT-PCR. LRP was highly expressed and suppressing LRP function increased doxorubicin accumulation in nuclei. This indicates LRP may be contributing to drug resistance in ATL patients, and the suppression of LRP function could be a new strategy for ATL treatment.     

Overlapping phenotypes of multidrug resistance among panels of human cancer-cell lines

In addition to P-glycoprotein (Pgp), 2 proteins related to multidrug resistance (MDR) have recently been described. The Multidrug-Resistance-associated protein (MRP) is one of the ATP-binding-cassette (ABC) transporters. The Lung-Resistance Protein (LRP) is the major component of human vaults, which are newly described cellular organelles and thought to mediate intracellular transport processes. Using immunocytochemical methods, we have examined the expression of MRP and LRP among panels of human cancer-cell lines not selected for drug resistance which have been previously characterized for expression of Pgp, and in vitro response to a variety of anti-cancer drugs. Expression of MRP and LRP was observed in 47/55 (87%) and 46/59 (78%) cell lines, respectively. Statistically significant correlations were observed between expression of each of these 3 proteins and in vitro sensitivity to at least one drug classically associated with MDR. LRP showed the greatest individual predictive value, which also applied to several non-classical MDR drugs. Co-expression of 2–3 MDR-related proteins was observed in 64% of the lines and was, in general, associated with high relative levels of drug resistance. Previously identified “classic” MDR lines as well as “pan-resistant” lines concurrently expressed all 3 MDR-related proteins. Some highly drug-resistant cell lines without detectable MDRI/Pgp were found to express relatively high levels of MRP and LRP. The high prevalence of MRP and LRP expression observed in this large set of cell lines, which have not been subjected to laboratory drug selection, suggests that MDR mechanisms associated with these proteins may be widespread in human malignancies. Moreover, the overlapping of these more recently recognized MDR phenotypes with Pgp-type MDR results in a complex phenotype, the understanding of which may be of importance in the development of new drugs and design of clinical treatment protocols, particularly those seeking to employ strategies to reverse the MDR phenotype. © 1996 Wiley-Liss, Inc.     

Leucine-rich protein 130 contributes to apoptosis resistance of human hepatocarcinoma cells

LRP130 is a ubiquitous protein involved in cellular homeostasis, microtubule alteration, and transactivation of a few multidrug resistance genes. Its role in resistance to apoptosis in HepG2 and HUH7 hepatocarcinoma cells was investigated. Using shRNA-producing lentiviruses to down-regulate the LRP130 gene, we showed that i) LRP130 did not affect the capacity of hepatocarcinoma cells to extrude drugs since LRP130 down-regulation was insufficient to significantly reduce P-glycoprotein production in these cells, and ii) the expression of 11 apoptosis-related genes measured by PCR-array was significantly reduced. Interestingly, six of these genes encode extrinsic pathway proapoptotic proteins whose expression was higher in LRP130-non producing than in LRP130-producing HepG2 cells. Fluorescence microscopy confirmed this new anti-apoptotic role of LRP130, which is strengthened by a significantly reduced cytochrome c oxidase activity in LRP130-down-regulated hepatocarcinoma cells.     

非霍奇金淋巴瘤多药耐药蛋白在淋巴结与骨髓液中表达的实验研究

 目的　探讨初发非霍奇金淋巴瘤（NHL）骨髓液和淋巴结活组织两种标本中多药耐药蛋白的表达及临床价值评估。方法　采用流式细胞术（FCM）活细胞免疫荧光法检测41例初治NHL淋巴结活组织中和37例骨髓液中瘤细胞多药耐药蛋白及反转录-聚合酶链反应（RT-PCR）半定量检测mdr1mRNA的表达,分析其与临床分期、恶性分级、乳酸脱氢酶（LDH）异常增高等的相关性。结果　两种标本中三种耐药基因单独及联合过度表达率无明显差异;淋巴结组织中,P-gp阳性表达在Ⅰ／Ⅱ期和Ⅲ／Ⅳ期之间有差别（P＝0.046）,与LDH异常增高相关（P＜0.05）,与恶性度分级无关（P＞0.1）;肺耐药蛋白（LRP）与三者都存在明显相关（P＜0.05）。而骨髓液中仅LRP与恶性分级和LDH异常增高明显相关（P＝0.01）,并未显示P-gp表达在不同分期的差异性;淋巴结中P-gp+的CR低于P-gp-（37.5 %,84.8 %;P＜0.01）;LRP+与LRP-的CR之间亦存在差别（53.3 %,88.5 %;P＜0.01）。结论　用淋巴结活组织进行耐药蛋白检测比骨髓能提供更准确的临床信息,且在肿瘤尚未发生骨髓转移时,取淋巴组织亦能进行耐药蛋白检测,及早指导临床治疗及预后。     

Expression of the lung resistance protein predicts poor outcome in patients with multiple myeloma.

Expression of the lung resistance protein (LRP) is associated with resistance to various anticancer drugs including melphalan and, therefore, may affect the clinical outcome in multiple myeloma (MM). To determine the clinical significance of LRP, we have compared LRP expression in bone marrow plasma cells with clinical parameters including response to chemotherapy and survival of previously untreated patients with MM (n = 72). LRP expression immunocytochemically assessed by means of the LRP-56 monoclonal antibody was positive (> or =10% staining plasma cells) in 44 (61%) samples. There was no correlation between LRP expression and age, sex, type of the paraprotein, serum creatinine, stage, beta2-microglobulin, serum lactate dehydrogenase, or C-reactive protein. However, LRP expression was more frequently observed in patients with a p53 deletion than in those without such a deletion (P = 0.01). The overall response rate for all of the patients evaluable for response to induction chemotherapy (n = 58) was 67%. The response rate was 87% for patients without LRP expression but only 54% for patients with LRP expression (P = 0.01). Kaplan-Meier analysis revealed that patients with LRP expression had a shorter overall survival (median, 33 months) than those without LRP expression (median not reached; P = 0.04). These data show that LRP expression is an important marker for clinical drug resistance and predicts a poor outcome in MM.     

Impaired breast cancer resistance protein mediated drug transport in plasma cells in multiple myeloma

The breast cancer resistance protein (BCRP/ABCG2) is an ATP-binding-cassette transporter involved in the transport of drugs used in the treatment of multiple myeloma (MM). Its expression, function and clinical significance in MM, however, are unknown. We report that BCRP is preferentially expressed and functionally active in normal plasma cells but that its function is significantly impaired in plasma cells in newly diagnosed MM. The data presented argue against a role for BCRP in primary drug resistance in MM and the utilisation as a molecular target as such but warrant research into its (patho)physiological role in normal and malignant plasma cells.     

Multidrug resistance genes in infant acute lymphoblastic leukemia: Ara-C is not a substrate for the breast cancer resistance protein.

Infants with acute lymphoblastic leukemia (ALL) are more resistant to chemotherapeutic drugs than older children with ALL, except for Ara-C. Drug resistance mechanisms in infant ALL, however, remain unknown. Possibly, multidrug resistance (MDR) proteins like P-glycoprotein, MDR-associated protein (MRP1), lung resistance-related protein (LRP/MVP) and the breast cancer resistance protein (BCRP) play a role. Accordingly, we measured the mRNA levels of these proteins in infants (n=13) and non-infants (n=13) with ALL, using quantitative RT-PCR. Infants expressed 2.4-fold less BCRP mRNA (P=0.009) than non-infants with ALL. MDR1, MRP1 and LRP/MVP expression did not differ between both groups. MDR gene expression levels did not correlate to prednisolone, vincristine, daunorubicin or Ara-C cytotoxicity, except for BCRP expression, which correlated with resistance to Ara-C (Rs=0.53, P=0.012), suggesting that Ara-C might be a BCRP substrate. However, culturing patients ALL cells in the presence of the BCRP inhibitor Ko143 had no effect on Ara-C sensitivity. Inhibiting Bcrp1 in the Mdr1a-, Mdr1b- and Mrp1-deficient and Bcrp1-overexpressing mouse cell line Mef3.8/T6400, also did not modulate Ara-C cytotoxicity. Therefore, we conclude that Ara-C is not a substrate for BCRP and that MDR proteins do not play a significant role in drug resistance in infant ALL.     

Effective therapy of experimental human malignant melanomas with a targeted cytotoxic somatostatin analogue without induction of multi-drug resistance proteins

Malignant melanomas are characterized by a high intrinsic resistance to chemotherapy. Multiple drug resistance (MDR) can be mediated by transport proteins such as MDR-1, multidrug resistance-associated protein (MRP) or lung resistance protein (LRP). The cytotoxic analogue of somatostatin AN-238 consisting of 2-pyrrolinodoxorubicin (AN-201) linked to a somatostatin analogue RC-121 binds to receptors for somatostatin and is targeted to tumors expressing these receptors. We evaluated the expression of somatostatin receptors on human malignant melanoma tumor lines MRI-H255 and MRI-H187 and examined the effects of the targeted analogue AN-238 and its cytotoxic radical AN-201 on growth of these tumors in nude mice. We also studied the effects of AN-238 and AN-201 on the expression of MDR-1, MRP-1 and LRP by real-time PCR. AN-238 inhibited the growth of MRI-H255 and MRI-H187 tumors while AN-201 was ineffective. Blockade of somatostatin receptors by somatostatin analogue RC-121 abolished the effects of AN-238. Targeted therapy with AN-238 did not produce an induction of mRNA of MDR-1, MRP-1 or LRP. Our findings show that targeted chemotherapy with cytotoxic somatostatin analogue AN-238 inhibits the growth of malignant melanomas. AN-238 could provide a novel treatment approach for advanced malignant melanomas.     

Soft tissue leiomyosarcomas and malignant gastrointestinal stromal tumors: differences in clinical outcome and expression of multidrug resistance proteins.

PURPOSE: Several studies have reported clinical behavior and chemotherapy resistance in leiomyosarcomas, but these studies did not differentiate between soft tissue leiomyosarcomas (LMS) and malignant gastrointestinal stromal tumors (GIST). Multidrug resistance (MDR) has been associated with the expression of P-glycoprotein (P-gp), multidrug resistance protein (MRP(1)), and lung resistance protein (LRP). The aim of the present study was to compare LMS and GIST with respect to clinical outcome and MDR parameters. PATIENTS AND METHODS: Clinical outcome was evaluated in 29 patients with a primary deep-seated LMS and 26 patients with a primary malignant GIST. Paraffin-embedded material, available for 26 patients with LMS and 25 with GIST, was used for immunohistochemical detection of P-gp, MRP(1), LRP, and c-kit. RESULTS: Mean overall survival (OS) was 72 months for LMS patients and 31 months for GIST patients (P: <.05). Metastases occurred in 16 (59%) of 27 assessable LMS patients and in 10 (56%) of 18 assessable GIST patients. LMS predominantly metastasized to the lungs (14 of 16 patients), whereas GIST tended to spread to the liver (five of 10 patients) and the abdominal cavity (three of 10 patients; P: <.001). P-gp and MRP(1) expression was more pronounced in GIST than in LMS (P: <.05): the mean percentage of P-gp expressing cells was 13.4% in patients with LMS and 38.4% in patients with GIST, and the mean percentage MRP(1) expressing cells was 13.3% in patients with LMS and 35.4% in patients with GIST. LRP expression did not differ between LMS and GIST. c-kit was expressed in 5% of the LMS patients and in 68% of the GIST patients. CONCLUSION: LMS patients have a better survival than GIST patients, and the metastatic pattern is different. Expression of MDR proteins in LMS is less pronounced than in GIST.