Multidrug resistance proteins in primary and metastatic soft-tissue sarcomas: down-regulation of P-glycoprotein during metastatic progression

BACKGROUND: Chemotherapy sensitivity of soft-tissue sarcomas (STS) is limited, which may be due to multidrug resistance (MDR). MDR is associated with expression of P-glycoprotein (P-gp), Multidrug Resistance-associated Protein 1 (MRP1) and Lung Resistance-related Protein (LRP). It is unknown whether in STS metastasis is more resistant than the primary counterpart. MATERIALS AND METHODS: In 35 chemonaive STS and their metastases (86% chemonaive), MDR proteins were immunohistochemically assessed. Eleven metastases presented synchronously, 24 metachronously. Expression was scored positive (>5% positive tumour cells) or negative. RESULTS: P-gp was positive in 31/34 primaries (91%), versus 22/32 metastases (69%) (p=0.005). This difference was significant for metachronous metastases (p=0.008). MRP1 was positive in 18/32 primaries (56%) and 22/33 metastases (67%). MRP1 was more expressed in synchronous metastases than primaries (p=0.047), but for the overall group this significance disappeared. LRP expression did not differ: 27/34 primaries (80%), versus 28/34 metastases (82%). CONCLUSION: P-gp, MRP1, LRP expression in the primary tumours was high. Metastatic progression did not coincide with MDR-protein up-regulation.     

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.     

老年人急性髓细胞白血病多药耐药蛋白过度表达的实验与临床研究

 目的　初步分析老年急性髓细胞白血病（AML）患者P-糖蛋白（P-gp）、多药耐药相关蛋白（MRP）、肺耐药蛋白（LRP）的表达及其在预后中的意义。方法　流式细胞仪活细胞直接或间接免疫荧光法检测12例初治老年AML（M2a 4例,其中1例由MDS转化而来;M4a 2例;M5a 5例;M6 1例）患者骨髓白血病细胞P-gp、MRP、LRP表达情况。分析这些多药耐药蛋白表达与预后的关系。结果　P-gp、MRP、LRP的表达率分别为58.33 %、8.33 %、50 %;P-gp(+)、MRP(+)0,P-gp(+)、LRP(+)33.33 %,MRP(+)、LRP(+)0,P-gp(+)、MRP(+)、LRP(+)8.33 %,P-gp(-)、MRP(-)、LRP(-)33.33 %,其中P-gp、LRP单独和二者共表达频率较高。P-gp(+)者的完全缓解（CR）率与2年总生存率（OS）均显著低于P-gp(-)者（P＝0.01）,LRP(+)者的CR率与2年OS亦均低于LRP(-)者。结论　老年AML患者 P-gp、LRP单独及二者共表达频率均较高。P-gp、LRP过度表达是老年AML患者的不良预后因素。     

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.     

耐药相关基因表达对Ⅲ期非小细胞肺癌新辅助化疗的临床预测价值探讨

背景与目的P-糖蛋白(P-glycoprotein,P-gp)、多药耐药相关蛋白(multidrugresistance-associatedprotein,MRP)、肺耐药蛋白(lungresistanceprotein,LRP)在多药耐药中发挥重要的作用,联合检测它们在评价非小细胞肺癌新辅助化疗中的价值国内外尚未见报道。本研究旨在探讨联合检测P-gp、MRP、LRP对Ⅲ期非小细胞肺癌新辅助化疗敏感性的预测价值。方法应用免疫组化技术检测31例行新辅助化疗的患者化疗前标本及化疗后手术标本。结果化疗前P-gp、MRP、LRP表达的阳性率分别为29.0%(9/31)、45.2%(14/31)及38.7%(12/31),化疗后分别为61.3%(19/31)、51.6%(16/31)及41.9%(13/31)。化疗前MRP和LRP同时阳性者32.3%(10/31),MRP与LRP具相关性(r=0.61,P<0.001)。化疗前P-gp、MRP、LRP表达阳性者化疗有效率分别为44.4%(4/9)、28.6%(4/14)及16.7%(2/12),MRP与LRP同时阳性者有效率为10.0%(1/10)。化疗有效的患者中位生存期为31个月,无效的为15个月,同期直接手术的患者为18个月。结论肿瘤中MRP与LRP共表达者化疗耐药的可能性很大,化疗有效率较低,新辅助化疗意义不大。     

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。     

肺癌组织中多药耐药基因及相关蛋白表达的研究

目的:探讨P-糖蛋白(P-glycopro-tein,P-gp)、肺癌耐药蛋白(lung cancer resis-tence protein,LRP)和多药耐药相关蛋白(multidrug resistence protein,MRP)在肺癌组织中的表达及其临床意义。方法:应用SP法检测116例术前未做化疗的肺癌组织中P-gp、LRP和MRP的表达水平。结果:P-gp在腺癌组织中的阳性表达率为78.26%(36/46),小细胞癌为63.64%(7/11),鳞状细胞癌为47.46%(28/59);三者相比差异有统计学意义,P=0.018。LRP在腺癌组织中的阳性表达率为89.13%(41/46),鳞状细胞癌为44.07%(26/59),小细胞癌为27.27%(3/11);三者相比差异有统计学意义,P=0.0001;MRP在不同癌组织中的表达差异无统计学意义,P=0.4165。在腺癌、鳞状细胞癌和小细胞癌组织中同时有两种或两种以上耐药基因产物表达阳性率分别为89.13%(41/46)、49.15%(29/59)和27.28%(3/11),三种类型间比较差异有统计学意义,P=0.0001。结论:不同组织学类型的肺癌存在不同程度的耐药性,检测P-gp、LRP和MRP的协同表达对于指导临床化疗方案的实施有重要意义。     

LRP,MRP,MDR1基因在非小细胞肺癌中的表达及其临床意义

目的 探讨肺耐药蛋白（ｌｕｎｇ ｒｅｓｉｓｔａｎｃｅ ｐｒｏｔｅｉｎ,ＬＲＰ）,多药耐药蛋白（ｍｕｌｔｉｄｒｕｇ ｒｅｓｉｓｔａｎｃｅａｓｓｏｃｉａｔｅｄ ｐｒｏｔｅｉｎ,ＭＲＰ）,和多药耐药基因（ｍｕｌｔｉｄｒｕｇ ｒｅｓｉｓｔａｎｅ,ＭＤＲ１）ｍＲＮＡ在非小细胞肺癌（ｎｏｎ－ｓｍａｌｌ ｃｅｌｌ ｃａｎｃｅｒ,ＮＳＣＬＣ）中的共表达及临床意义。方法 ＲＴ－ＰＣＲ检测ＮＳＣＬＣ冰冻组织中上述耐药     

High functional P-glycoprotein activity is more often present in T-cell acute lymphoblastic leukaemic cells in adults than in children

There is a distinct difference in prognosis between childhood versus adult acute lymphoblastic leukaemia (ALL). To define whether multidrug resistance (MDR) genes might contribute to this distinction, the expression and functional activity of P-glycoprotein (P-gp) and MDR associated proteins (MRP) were determined with RT-PCR (MDR-1, MRP1, MRP2, MRP3) and flow cytometry (P-gp and MRP). Patient samples were obtained from 36 children and 35 adults with de novo ALL. Of these patients, 38 showed a T-lineage and 33 showed a B-lineage immunophenotype. In the samples, large variability in P-gp activity (0.8-4.9) and MRP activity (1.1-13.9) was observed. Most T-ALL patients with high P-gp activity were adults (89%). The mRNA expression of MDR-1 correlated weakly with P-gp activity. In contrast, MRP activity did not correlate with the mRNA expression of MRP1, MRP2 and MRP3. In T-ALL, a worse overall survival and event-free survival was observed with increasing P-gp activity. P-gp activity had no prognostic impact in B-lineage ALL. In addition, high MRP activity did not influence treatment outcome in either T- or B-lineage ALL. Multivariate Cox regression analysis, showed P-gp activity to be the only unfavourable prognostic factor for overall survival in T-ALL. In conclusion, this study demonstrates the prognostic relevance of P-gp activity in T-ALL. Since the majority of the patients with high P-gp activity were adults, P-gp might contribute to the poor prognosis of adult T-ALL.     

Expression of P-glycoprotein, multidrug resistance-associated protein 1, and lung resistance-related protein in human soft tissue sarcomas before and after hyperthermic isolated limb perfusion with tumor necrosis factor-alpha and melphalan

BACKGROUND: Multidrug resistance (MDR) is associated with expression of P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1), and lung resistance-related protein (LRP). Tumor necrosis factor (TNF-alpha) is able to modify the expression of these three proteins in different cell types. The effect of TNF-alpha in the clinical situation on patients with soft tissue sarcomas (STS) is indeterminate. METHODS: Thirty-seven patients with a locally advanced extremity STS underwent hyperthermic isolated limb perfusion (HILP) with TNF-alpha and melphalan; 15 patients received additional interferon gamma. Clinical and histologic responses were documented and used to define the overall response. Samples before and after HILP were analyzed immunohistochemically for P-gp, MRP1, and LRP. Samples were scored as negative or positive (< or = 5% or > 5% positive tumor cells). RESULTS: Six patients had an overall complete response, 25 patients had a partial response, and 4 patients with STS revealed no change; in 2 patients, the response remained unclear. The percentage STS samples that were positive for all three proteins dropped from 92% before HILP to 85% after HILP. P-gp positive samples were encountered more often than MRP1 positive samples (P < 0.05). The percentage of samples that were negative for all three MDR proteins increased after HILP from 6% to 16%. MDR status had no significant correlation with tumor response. CONCLUSIONS: HILP with TNF-alpha and melphalan results in excellent overall tumor response in patients with locally advanced STS. STS more often are positive for P-gp than for MRP1. MDR status in patients with STS is not predictive for tumor response after HILP. Data from the current study suggest that the combination of TNF-alpha and melphalan does not induce MDR positive STS: a result with clinical importance when consecutive, adjuvant, doxorubicin-containing chemotherapy is considered.     

非小细胞肺癌血管生成因子与耐药相关基因关系的研究

目的:探讨血管生成因子(VEGF、bFGF)和耐药相关基因(MDR1、MRP、LRP)在非小细胞肺癌(non-smallcelllungcancer,NSCLC)中的表达及相互关系。方法:应用免疫组化技术检测96例NSCLC组织中VEGF、bFGF、MDR1、MRP、LRP蛋白表达,其中36例应用RT-PCR技术检测上述基因mRNA表达。结果:VEGF、bFGF、MDR1、MRP、LRPmRNA表达率分别为69.5%(25/36)、52.8%(19/36)、33.3%(12/36)、52.8%(19/36)、50.0%(18/36);蛋白表达率分别为51.0%(49/96)、58.3%(56/96)、45.8%(44/96)、59.4%(57/96)、64.6%(62/96),各基因mRNA表达与蛋白表达基本一致。统计分析表明:VEGF表达与MDR1、LRP表达相关(P=0.025,P=0.022),与MRP表达无关(P=0.428);bFGF表达与MDR1、LRP表达相关(P=0.001,P=0.012),并与MRP+LRP共表达相关(P=0.001)。结论:在非小细胞肺癌中血管生成因子与耐药相关基因具有一定的相关性。     

Multidrug resistance proteins in rhabdomyosarcomas: comparison between children and adults

BACKGROUND: Pediatric rhabdomyosarcomas (RMS) have a more advantageous prognosis after multimodality treatment compared with adult RMS, which might be related to a decreased sensitivity to chemotherapy in adults. Resistance to chemotherapy might be conveyed by the multidrug resistance (MDR)-associated proteins P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1), and lung resistance-related protein (LRP). It was therefore suggested that these proteins were expressed differently in pediatric and adult patients. METHODS: The expression of P-gp, MRP1, and LRP was assessed immunohistochemically in 45 specimens of untreated RMS: 29 were obtained from children younger than 16 years old and 16 were obtained from adults. All children had an embryonal or botryoid RMS. Among the adults, there were 10 embryonal, 3 alveolar, and 3 pleomorphic RMS. Samples were scored as negative or positive according to the percentage of immunoreactive tumor cells: 0.5 (1-5%), 1 (5-25%), 2 (26-50%), 3 (51-75%), or 4 (> 75%). RESULTS: Expression of LRP was more pronounced in embryonal and pleomorphic RMS in adults compared with RMS in children. In addition, LRP expression correlated with age at diagnosis. Alveolar RMS had remarkably low LRP expression. Expression of P-gp and MRP1 did not differ significantly between children and adults. CONCLUSIONS: In this series of embryonal and pleomorphic RMS, an increased LRP expression was observed in adults, which may explain their worse response to chemotherapy reported in other studies. In alveolar RMS, a low LRP expression was observed, suggesting that other mechanisms are responsible for the resistant phenotype in most of these tumors.     

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.     

Clinical relevance of the lung resistance protein in diffuse large B-cell lymphomas.

Drug resistance of non-Hodgkin's lymphomas may involve mechanisms of the multidrug resistance phenotype including the lung resistance protein (LRP) and the multidrug resistance protein (MRP1). To determine the clinical relevance of these multidrug resistance factors in previously untreated diffuse large B-cell lymphomas (n = 48), we studied LRP and MRP1 expression in lymphoma cells and their impact on clinical outcome. LRP and MRP1 expression were immunohistochemically assessed by means of the monoclonal antibodies LRP-56 and MRPr1, respectively. LRP was positive in 23% and MRP1 in 44% of the samples. LRP expression was associated with higher tumor stage (P = 0.03), elevated serum lactate dehydrogenase levels (P = 0.01), and the International Prognostic Index (P = 0.0001). LRP-positive patients had a lower complete response rate to polychemotherapy than LRP-negative patients (18 versus 65%; P = 0.006). Patients with LRP expression had a shorter overall survival than those without LRP expression (median of 0.9 years versus median not reached; P = 0.001). MRP1 expression was independent of clinical and laboratory parameters and had no impact on the outcome of chemotherapy or survival of the patients. These data suggest that LRP expression but not MRP1 expression is an important mechanism of drug resistance associated with worse clinical outcome in previously untreated diffuse large B-cell lymphomas. Thus, the reversal of LRP-mediated drug resistance may improve clinical outcome in diffuse large B-cell lymphoma in the future.     

Lung resistance-related protein as a predictor of clinical outcome in advanced testicular germ-cell tumours

This study was undertaken to investigate the expression and predictive value for outcome of multidrug resistance-associated (MDR) proteins P-glycoprotein (Pgp), MRP1, BCRP, and LRP, in advanced testicular germ-cell tumours (TGCT). Paraffin-embedded sections from 56 previously untreated patients with metastatic TGCT were immunostained for Pgp, MRP1, BCRP, and LRP. All patients received platinum-based chemotherapy after orchidectomy. Immunostaining was related to clinicopathological parameters, response to chemotherapy, and outcome. Strong and intermediate expressions of the different MDR-related proteins were: 27 and 41% (Pgp), 54 and 37% (MRP1), 86 and 7% (BCRP), and 14 and 29% (LRP). P-glycoprotein and MRP1 associated, respectively, to low AFP (P=0.026) and high LDH levels (P=0.014), whereas LRP expression associated with high beta-hCG levels (P=0.003) and stage IV tumours (P=0.029). No correlation was found between Pgp, MRP1, and BCRP expression and response to chemotherapy and survival. In contrast, patients with LRP-positive tumours (strong or intermediate expression) had shorter progression-free (P=0.0006) and overall survival (P=0.0116) than LRP-negative patients, even after individual log-rank adjustments by statistically associated variables. Our data suggest that a positive LRP immunostaining at the time of diagnosis in metastatic TGCT is associated with an adverse clinical outcome.     

胃癌中P-糖蛋白、多药耐药相关蛋白、肺耐药蛋白的表达及其意义

 目的　检测胃癌组织中P-糖蛋白（P-gp）、多药耐药相关蛋白（MRP）、肺耐药蛋白（LRP）的表达,分析其与胃癌临床病理因素的关系。方法　采用免疫组织化学SP法对59例胃癌患者癌组织进行研究。结果　在59例胃癌患者中P-gp阳性率最高[86.4 %（51例）],其次为LRP[84.7 %（50例）],二者呈正相关（r＝0.803）;MRP阳性率最低[27.1 %（16例）]。P-gp、MRP、LRP与分化程度无关（均P＞0.05）。P-gp与临床分期呈正相关（r＝0.742）,MRP、LRP均与胃癌浸润深度、淋巴结转移与否及分化程度无关。结论　P-gp、MRP、LRP在未接受化疗胃癌组织中高表达,提示胃癌中存在P-gp、MRP、LRP介导的原发性耐药。     

The clinical relevance of the expression of several multidrug-resistant-related genes in patients with primary acute myeloid leukemia

Multidrug resistance (MDR) is a complex phenomenon that includes the expression of many different genes regulating drug transport or metabolism, cellular repair or detoxification mechanisms. The co-expression of several genes could be at the basis of the resistant phenotype in vivo. In order to test a possible prognostic role of the expression and co-expression of several MDR-related genes (MDR1, topoisomerase IIalpha, topoisomerase IIbeta, MRP, GSTpi, LRP), 35 patients affected by acute myeloid leukemia (AML) were tested by RT-PCR assays. In our series, topoisomerase IIbeta was significantly co-expressed with MRP (p = 0.05), GSTpi (p = 0.017) and LRP (p = 0.005). GSTpi was co-expressed with LRP (p = 0.03) and MRP (p = 0.007); on the other hand, 53.8% of patients were LRP and MRP-positive (p = 0.02). The PCR-positivity did not differ according to biological/clinical characteristics of patients, including age; this latter was the only parameter conditioning the response and overall survival. Neither the expression nor the co-expression of the tested genes was significantly correlated with the response to the induction treatment and long-term outcome.