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Supplementary Figures 1-2 from Lapatinib (Tykerb, GW572016) Reverses Multidrug Resistance in Cancer Cells by Inhibiting the Activity of ATP-Binding Cassette Subfamily B Member 1 and G Member 2

Lapatinib is active at the ATP-binding site of tyrosine kinases that are associated with the human epidermal growth factor receptor (Her-1 or ErbB1) and Her-2. It is conceivable that lapatinib may inhibit the function of ATP-binding cassette (ABC) transporters by binding to their ATP-binding sites. The aim of this study was to investigate the ability of lapatinib to reverse tumor multidrug resistance (MDR) due to overexpression of ABC subfamily B member 1 (ABCB1) and ABC subfamily G member 2 (ABCG2) transporters. Our results showed that lapatinib significantly enhanced the sensitivity to ABCB1 or ABCG2 substrates in cells expressing these transporters, although a small synergetic effect was observed in combining lapatinib and conventional chemotherapeutic agents in parental sensitive MCF-7 or S1 cells. Lapatinib alone, however, did not significantly alter the sensitivity of non-ABCB1 or non-ABCG2 substrates in sensitive and resistant cells. Additionally, lapatinib significantly increased the accumulation of doxorubicin or mitoxantrone in ABCB1- or ABCG2-overexpressing cells and inhibited the transport of methotrexate and E217βG by ABCG2. Furthermore, lapatinib stimulated the ATPase activity of both ABCB1 and ABCG2 and inhibited the photolabeling of ABCB1 or ABCG2 with [125I]iodoarylazidoprazosin in a concentration-dependent manner. However, lapatinib did not affect the expression of these transporters at mRNA or protein levels. Importantly, lapatinib also strongly enhanced the effect of paclitaxel on the inhibition of growth of the ABCB1-overexpressing KBv200 cell xenografts in nude mice. Overall, we conclude that lapatinib reverses ABCB1- and ABCG2-mediated MDR by directly inhibiting their transport function. These findings may be useful for cancer combinational therapy with lapatinib in the clinic. [Cancer Res 2008;68(19):7905–14]

We investigated soil C:N:P stoichiometry and nutrient dynamics of在福建省白砂国有林场选取幼龄林(5年)、中幼龄林(8年)、近熟林(21年)、成熟林(27年)和过熟林(40年)5个生长阶段的杉木人工林,测定不同土层(0～10、10～20、20～40 cm)土壤总碳(TC)、全氮(TN)、全磷(TP)、全钾(TK)、全钙(Ca)、全镁(Mg)含量以及C∶N∶P化学计量比,探究杉木人工林土壤碳氮磷(C∶N∶P)化学计量特征与养分随林龄的变化规律。结果表明: 随着林分发育,TC、TN未发生显著变化,土壤C∶N保持不变。随着林分发育,0～20 cm土层土壤TP含量呈增加-降低-增加的变化趋势,其中在杉木成熟林达到最低,C∶P和N∶P最大,而20～40 cm土层土壤TP在各个林龄之间无显著变化。Ca、Mg含量在所有土层均在杉木成熟林达到最低。土壤TC与C∶P、N∶P、C∶N均呈显著正相关,TP与C∶P、N∶P呈显著负相关,土壤TP含量是调控土壤C∶P和N∶P的关键因子。杉木人工林发育到成熟期受到P的限制,为保证人工林正常发育,可在杉木速生阶段施加P肥,促进养分良性循环。适当提高杉木林的轮伐期可能会有利于土壤养分的恢复与保持。.

Phosphorus (P) limitation is one of the major issues for the management of subtropical plantations. Understanding the effects of tree species transition from conifer to broadleaved trees on soil P fraction and availability in different soil layers are of great significance for the sustainable development of subtropical forests. We compared changes in soil chemical properties, P fraction and availability across 0-100 cm soil profile between Mytilaria laosensis and Cunninghamia lanceolata plantations, which were initially reforested from C. lanceolata plantation in the spring of 1993. The results showed that soil organic P content in both plantations decreased significantly with soil depth. Compared with C. lanceolata, the M. laosensis plantation significantly increased soil available P content by 35.7% and 86.2% in the 0-10 and 10-20 cm, respectively. The contents of soil labile P and moderately labile P decreased significantly with soil depth in both plantations. The contents of labile P and moderately labile P were significantly higher in the surface soil (0-20 cm), while the non-labile P in the 80-100 cm was increased by 13.6%, and the free iron content in the 20-80 cm significantly decreased. Results of redundancy analysis showed that dissolved organic carbon and free iron were the most important factors influencing P fraction in those plantations. Tree species transition from C. lanceolata to M. laosensis could change the pattern of soil P fraction in soil profile, and greatly enhance soil P availability.磷限制是亚热带人工林经营面临的主要问题之一,研究阔叶树代替针叶树造林对不同土壤层次磷组分和有效性的影响对维持亚热带地区森林生态系统的可持续发展具有重要意义。以1993 年春天在二代杉木林采伐迹地上同时营造的阔叶树米老排人工林和针叶树杉木人工林为对象,研究0～100 cm不同土层土壤理化性质、磷组分及其有效性的变化。结果表明: 两种林分下土壤有机磷含量均随土层加深而显著下降;与杉木林相比,米老排林0～10 和10～20 cm土层有效磷含量显著增加,分别增加35.7%和86.2%,易分解态磷和中等易分解态磷均随土层加深而显著降低,表层(0～20 cm)土壤易分解态磷和中等易分解态磷含量显著增加,80～100 cm土层难分解态磷含量显著降低,下降13.6%,20～80 cm土层游离态铁含量显著降低。冗余分析表明,可溶性有机碳和游离态铁是土壤磷组分变化的关键影响因子。在杉木采伐迹地上营造阔叶树改变了磷在土壤剖面上的分布格局,有利于提高磷的有效性。.

Fine roots play a critical role in terrestrial carbon and nutrient cycling. Despite this, quantitative evaluation of the fine root dynamics in plantations and natural secondary forests is lacking. This study examined the dynamics of fine root biomass and necromass of Chinese fir plantations and natural secondary forests (5–41 years old) and employed primary forests as a reference in subtropical China. In the top 60-cm soil depth, the sum of fine root biomass of Chinese fir plantations and natural secondary forests initially increased and then decreased with stand development, attaining a peak in the 27–31-year age class. The total fine root biomass of natural secondary forests was significantly higher than that of Chinese fir plantations across all age classes. The total fine root biomass of primary forests was similar to that in the 38–41-year-old natural secondary forests and Chinese fir plantations. The total fine root necromass was higher in Chinese fir plantations than in natural secondary forests across all ages except in the youngest age class. The necromass to biomass ratio was significantly higher in Chinese fir plantations. Most of the fine root biomass resided in the topsoil (0–10 cm) for all stand types and ages. The higher fine root biomass in the secondary natural forests than in the Chinese fir plantation was most apparent in the topsoil. Across all age classes, the fine root biomass was positively correlated with stand basal area, mean diameter at breast height, and shrub cover, whereas the fine root necromass and the necromass to biomass ratio tended to be more consistent across measured stand characteristics. Our results highlight profound influences of forest management on fine root biomass and necromass and suggest that the low fine root biomass of Chinese fir plantations may have a negative impact on carbon and nutrient cycling in the subtropical forests.

The aim of this study was to investigate the effect of neutral microporous resin hemoperfusion on oxygenation improvement, removal of inflammatory cytokines in plasma and bronchoalveolar lavage, and mortality in acute lung injury induced by extrapulmonary sepsis. Forty-six patients with acute lung injury induced by extrapulmonary sepsis were randomized to HA type hemoperfusion treatment (N=25) or standard therapy (N=21). Those undergoing hemoperfusion treatment received HA330 hemoperfusion. We measured the plasma and bronchoalveolar lavage concentrations of TNF-α and IL-1, and the following parameters were compared between the control group and the hemoperfusion group on days 0, 3 and 7: lung injury measurements (arterial oxygen tension/fractional inspired oxygen ratio, lung injury score, chest X-ray score); interstitial edema of lung (extravascular lung water). Duration of mechanical ventilation, hospital, 28-day, and intensive care unit mortality were also observed. Patients treated with HA hemoperfusion showed a significant removal of plasma and bronchoalveolar lavage TNF-α and IL-1 over time while in the study. Patients in the HA group also demonstrated not only significant improvement of PaO2 /FiO2 , but also decreased Lung Injury Score and chest X-ray score at days 3 and 7. Furthermore, the measurements of the arterial oxygen tension/fractional inspired oxygen ratio, lung injury score and extravascular lung water (EVLWI) significantly correlated with and the concentration of cytokines in the plasma (all P

The aim of this study is to evaluate the impact of neutral microporous resin hemoperfusion on hemodynamic improvement, removal of inflammatory cytokines, and mortality in critical care patients with severe sepsis. Forty-four patients with severe sepsis or septic shock were randomized to HA type hemoperfusion treatment (N=24) or standard therapy (N=20). Those undergoing hemoperfusion treatment received HA330 hemoperfusion. We measured the plasma concentrations of IL-6 and IL-8 at the start of every hemoperfusion treatment, and the following parameters were compared between the control group and the hemoperfusion group on days 3, 7, and 14: hemodynamics (cardiac index, systemic vascular resistance index, heart rate, and mean arterial pressure); change of hematology and coagulation function; organ function; and the sequential organ failure assessment (SOFA) score. Hospital, 28-day, and ICU mortality were also observed. Patients treated with HA hemoperfusion showed a significant removal of plasma IL-6 and IL-8 over time while in the study. Patients in the HA group also demonstrated significant increases in cardiac index, systemic vascular resistant index, fast withdrawal of vasoactive agents and decreases in heart rate compared with the controls at days 3 and 7. Although there was no significant difference between the groups in organ dysfunction as assessed by SOFA scores from day 0 (baseline) to day 7, significant improvement can be demonstrated in the hemoperfusion group at day 14. There was no significant difference between the groups in 28-day mortality, hospital mortality, or length of hospital stay, but ICU mortality and the length of ICU stay in the HA group were markedly reduced. Hemoperfusion treatment using the HA type cartridge in sepsis is safe and it may improve organ dysfunction, ICU mortality, and shorten the length of ICU stay. Clinical significant removal of inflammatory cytokines such as IL-6 and IL-8 from circulation by hemoperfusion may contribute to improving a patient's outcome in an ICU.

Lapatinib is active at the ATP-binding site of tyrosine kinases that are associated with the human epidermal growth factor receptor (Her-1 or ErbB1) and Her-2. It is conceivable that lapatinib may inhibit the function of ATP-binding cassette (ABC) transporters by binding to their ATP-binding sites. The aim of this study was to investigate the ability of lapatinib to reverse tumor multidrug resistance (MDR) due to overexpression of ABC subfamily B member 1 (ABCB1) and ABC subfamily G member 2 (ABCG2) transporters. Our results showed that lapatinib significantly enhanced the sensitivity to ABCB1 or ABCG2 substrates in cells expressing these transporters, although a small synergetic effect was observed in combining lapatinib and conventional chemotherapeutic agents in parental sensitive MCF-7 or S1 cells. Lapatinib alone, however, did not significantly alter the sensitivity of non-ABCB1 or non-ABCG2 substrates in sensitive and resistant cells. Additionally, lapatinib significantly increased the accumulation of doxorubicin or mitoxantrone in ABCB1- or ABCG2-overexpressing cells and inhibited the transport of methotrexate and E217βG by ABCG2. Furthermore, lapatinib stimulated the ATPase activity of both ABCB1 and ABCG2 and inhibited the photolabeling of ABCB1 or ABCG2 with [125I]iodoarylazidoprazosin in a concentration-dependent manner. However, lapatinib did not affect the expression of these transporters at mRNA or protein levels. Importantly, lapatinib also strongly enhanced the effect of paclitaxel on the inhibition of growth of the ABCB1-overexpressing KBv200 cell xenografts in nude mice. Overall, we conclude that lapatinib reverses ABCB1- and ABCG2-mediated MDR by directly inhibiting their transport function. These findings may be useful for cancer combinational therapy with lapatinib in the clinic. [Cancer Res 2008;68(19):7905–14]

The aim of this study was to investigate the effect of neutral microporous resin hemoperfusion on oxygenation improvement, removal of inflammatory cytokines in plasma and bronchoalveolar lavage, and mortality in acute lung injury induced by extrapulmonary sepsis. Forty-six patients with acute lung injury induced by extrapulmonary sepsis were randomized to HA type hemoperfusion treatment (N=25) or standard therapy (N=21). Those undergoing hemoperfusion treatment received HA330 hemoperfusion. We measured the plasma and bronchoalveolar lavage concentrations of TNF-α and IL-1, and the following parameters were compared between the control group and the hemoperfusion group on days 0, 3 and 7: lung injury measurements (arterial oxygen tension/fractional inspired oxygen ratio, lung injury score, chest X-ray score); interstitial edema of lung (extravascular lung water). Duration of mechanical ventilation, hospital, 28-day, and intensive care unit mortality were also observed. Patients treated with HA hemoperfusion showed a significant removal of plasma and bronchoalveolar lavage TNF-α and IL-1 over time while in the study. Patients in the HA group also demonstrated not only significant improvement of PaO2 /FiO2 , but also decreased Lung Injury Score and chest X-ray score at days 3 and 7. Furthermore, the measurements of the arterial oxygen tension/fractional inspired oxygen ratio, lung injury score and extravascular lung water (EVLWI) significantly correlated with and the concentration of cytokines in the plasma (all P0.05). The HA hemoperfusion treatment group had a significant reduction in duration of mechanical ventilation, length of intensive care unit stay, and intensive care unit mortality. Significant removal of inflammatory cytokines from circulation and lung by hemoperfusion treatment using the HA type cartridge may contribute to the improvement of lung injury and intensive care unit outcome in extrapulmonary septic patients.

The aim of this study is to evaluate the impact of neutral microporous resin hemoperfusion on hemodynamic improvement, removal of inflammatory cytokines, and mortality in critical care patients with severe sepsis. Forty-four patients with severe sepsis or septic shock were randomized to HA type hemoperfusion treatment (N=24) or standard therapy (N=20). Those undergoing hemoperfusion treatment received HA330 hemoperfusion. We measured the plasma concentrations of IL-6 and IL-8 at the start of every hemoperfusion treatment, and the following parameters were compared between the control group and the hemoperfusion group on days 3, 7, and 14: hemodynamics (cardiac index, systemic vascular resistance index, heart rate, and mean arterial pressure); change of hematology and coagulation function; organ function; and the sequential organ failure assessment (SOFA) score. Hospital, 28-day, and ICU mortality were also observed. Patients treated with HA hemoperfusion showed a significant removal of plasma IL-6 and IL-8 over time while in the study. Patients in the HA group also demonstrated significant increases in cardiac index, systemic vascular resistant index, fast withdrawal of vasoactive agents and decreases in heart rate compared with the controls at days 3 and 7. Although there was no significant difference between the groups in organ dysfunction as assessed by SOFA scores from day 0 (baseline) to day 7, significant improvement can be demonstrated in the hemoperfusion group at day 14. There was no significant difference between the groups in 28-day mortality, hospital mortality, or length of hospital stay, but ICU mortality and the length of ICU stay in the HA group were markedly reduced. Hemoperfusion treatment using the HA type cartridge in sepsis is safe and it may improve organ dysfunction, ICU mortality, and shorten the length of ICU stay. Clinical significant removal of inflammatory cytokines such as IL-6 and IL-8 from circulation by hemoperfusion may contribute to improving a patient's outcome in an ICU.

Nilotinib, a BCR-Abl tyrosine kinase inhibitor (TKI), was developed to surmount resistance or intolerance to imatinib in patients with Philadelphia positive chronic myelogenous leukemia. Recently, it was shown that several human multidrug resistance (MDR) ATP-binding cassette (ABC) proteins could be modulated by specific TKIs. MDR can produce cancer chemotherapy failure, typically due to overexpression of ABC transporters, which are involved in the extrusion of therapeutic drugs. Here, we report for the first time that nilotinib potentiates the cytotoxicity of widely used therapeutic substrates of ABCG2, such as mitoxantrone, doxorubicin, and ABCB1 substrates including colchicine, vincristine, and paclitaxel. Nilotinib also significantly enhances the accumulation of paclitaxel in cell lines overexpressing ABCB1. Similarly, nilotinib significantly increases the intracellular accumulation of mitoxantrone in cells transfected with ABCG2. Furthermore, nilotinib produces a concentration-dependent inhibition of the ABCG2-mediated transport of methotrexate (MTX), as well as E(2)17betaG a physiological substrate of ABCG2. Uptake studies in membrane vesicles overexpressing ABCG2 have indicated that nilotinib inhibits ABCG2 similar to other established TKIs as well as fumitremorgin C. Nilotinib is a potent competitive inhibitor of MTX transport by ABCG2 with a K(i) value of 0.69+/-0.083 microM as demonstrated by kinetic analysis of nilotinib. Overall, our results indicate that nilotinib could reverse ABCB1- and ABCG2-mediated MDR by blocking the efflux function of these transporters. These findings may be used to guide the design of present and future clinical trials with nilotinib, elucidating potential pharmacokinetic interactions. Also, these findings may be useful in clinical practice for cancer combination therapy with nilotinib.

Over-expression of ABC transporters are involved in the extrusion of therapeutic drugs, leading to MDR, which can eventually produce cancer chemotherapy failure. Previously, it was shown that specific TKIs could modulate several human multidrug resistance (MDR) ATP-binding cassette (ABC) proteins. Recently discovered second generation, BCR-Abl tyrosine kinase inhibitor (TKI), Nilotinib was developed to surmount resistance or intolerance to imatinib in patients with Philadelphia positive chronic myelogenous leukemia. Here, we report for the first time that nilotinib not only potentiates the cytotoxicity of widely used therapeutic substrates of ABCB1, such as colchicine, vincristine, and paclitaxel, but also that of ABCG2 substrates such as mitoxantrone and doxorubicin. Nilotinib also significantly enhances the intracellular accumulation of methotrexate (MTX) in cells transfected with ABCG2. Similarly, nilotinib significantly increases the accumulation of paclitaxel in cell lines overexpressing ABCB1. Furthermore, nilotinib produces a concentration-dependent inhibition of the ABCG2-mediated transport of MTX, as well as E217βG a physiological substrate of ABCG2. Uptake studies in membrane vesicles over-expressing ABCG2 have indicated that nilotinib inhibits ABCG2 similar to other established TKIs as well as fumitremorgin C. In addition, the kinetic analysis demonstrated that nilotinib is a potent competitive inhibitor of MTX transport by ABCG2 with a Ki value of 0.69+/-0.083 μM. To sum it up, our results indicate that nilotinib could reverse ABCB1- and ABCG2-mediated MDR by blocking the efflux function of these transporters. These findings may be useful in clinical practice for cancer combination therapy with nilotinib and may be vital to the design of present and future clinical trials with nilotinib, elucidating potential pharmacokinetic interactions. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1531.