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ABSTRACT: Low-dose metronomic (LDM) chemotherapy is emerging as an alternative or supplemental dosing strategy to conventional maximum tolerated dose (MTD) chemotherapy. It is characterized primarily, but not exclusively, by antiangiogenic mechanisms of action and the absence of high-grade adverse effects commonly seen with MTD chemotherapy. However, similar to other anticancer therapies, inherent resistance to LDM chemotherapy is common. Moreover, even tumors that initially respond to metronomic regimens eventually develop resistance through mechanisms that are as yet unknown. Thus, we have developed in vivo models of PC-3 human prostate cancer cells resistant to extended LDM cyclophosphamide therapy. Such PC-3 variants show stable resistance to LDM cyclophosphamide in vivo yet retain in vitro sensitivity to 4-hydroperoxy-cyclophosphamide (precursor of the active cyclophosphamide metabolite 4-hydroxy-cyclophosphamide) and other chemotherapeutic agents, namely, docetaxel and doxorubicin. Moreover, LDM cyclophosphamide-resistant PC-3 variants remain sensitive to MTD cyclophosphamide therapy in vivo. Conversely, PC-3 variants made resistant in vivo to MTD cyclophosphamide show varying levels of resistance to metronomic cyclophosphamide when grown in mice. These results and additional studies of variants of the breast cancer cell line MDA-MB-231 suggest that resistance to LDM cyclophosphamide is a distinct phenomenon from resistance to MTD cyclophosphamide and that LDM cyclophosphamide administration does not select for MTD chemotherapy resistance. As such, our findings have various implications for the clinical use of metronomic chemotherapy.
Neoplasia (New York, N.Y.) 01/2011; 13(1):40-8. · 5.48 Impact Factor
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Nature 12/2010; 468(7324):637-8. · 36.28 Impact Factor
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ABSTRACT: Acquired resistance to antiangiogenic drugs, such as sorafenib, is a major clinical problem. We studied development of a resistance to sorafenib in new preclinical models of human hepatocellular carcinoma (HCC) along with a strategy to delay such resistance--combination with metronomic chemotherapy. Three different xenograft models were studied using human Hep3B HCC cells, which are highly responsive to sorafenib, namely, orthotopic and subcutaneous transplant in severe combined immunodeficient mice, and an orthotopic transplant in nude mice. The complementary DNA for the β-subunit of human choriogonadotropin was transfected into HCC cells, and urine levels of the protein were monitored as a surrogate of tumor burden. Extended daily treatments, sometimes interrupted by a break period of 3 to 7 days to allow recovery from toxicity at sorafenib doses of 30 to 60 mg/kg, were maintained until and after evidence of tumor relapse. Initially responsive tumors seemed to develop a resistance-like phenotype after long-term daily treatment (e.g., >42 days) at doses of 30 to 60 mg/kg. Transplantation of cell lines established from progressing tumors into new hosts showed that the resistant phenotype was not propagated. Furthermore, a regimen of daily metronomic uracil + tegafur (UFT, an oral 5-fluorouracil prodrug) chemotherapy with a less toxic regimen of sorafenib (15 mg/kg per day) significantly delayed the onset of resistance (>91 days). In conclusion, development of a resistance-like phenotype to sorafenib is reversible, and metronomic UFT plus sorafenib may be a promising and well-tolerated treatment for increasing efficacy by delaying emergence of such resistance.
Neoplasia (New York, N.Y.) 11/2010; 12(11):928-40. · 5.48 Impact Factor
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Gunita Mitera,
Alysa Fairchild,
Carlo DeAngelis, Urban Emmenegger,
Laura Zurawel-Balaura,
Liying Zhang,
Andrea Bezjak,
Wilfred Levin,
Michael Mclean,
Nadil Zeiadin,
Jocelyn Pang,
Janet Nguyen,
Emily Sinclair,
Edward Chow,
Rebecca Wong
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ABSTRACT: Determine adequacy of management of pain secondary to bone metastases by physicians referring to specialized outpatient palliative radiotherapy (RT) clinics in Canada; compare geographic differences in adequacy of pain management and pain severity between these cohorts; compare results with published international literature.
Prospectively collected data from three participating centers were used to calculate the Pain Management Index (PMI) by subtracting the patient-rated pain score at time of initial clinic visit from the analgesic score. Scores were 0, 1, 2, and 3 when patients reported no pain (0), mild (1-4), moderate (5-6), or severe pain (7-10), respectively, on the Edmonton Symptom Assessment System or Brief Pain Inventory. Analgesic scores of 0, 1, 2, and 3 were assigned for no pain medication, nonopioids, weak opioids, and strong opioids respectively. A negative PMI suggests inadequate pain management.
Overall incidence of negative PMI and moderate to severe pain was 25.1% and 70.9% respectively for 2011 patients. Comparing the three participating centers, the incidence of negative PMI was 31.0%, 20.0%, and 16.8% (p < 0.0001), and severe pain was 55.5%, 48.2% and 43.4% (p < 0.0001), these correlated with a negative PMI. Patients referred to our clinics were less likely to be undertreated for their pain when compared to study results from international countries.
Geographic differences in adequacy of analgesic management for painful bone metastases exist between Canadian specialized outpatient palliative RT clinics and between centers globally. Investigating reasons for these differences may provide insight into solutions to improve quality of life for these patients.
Journal of palliative medicine 05/2010; 13(5):589-93. · 1.84 Impact Factor
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ABSTRACT: By frequent and protracted administration of conventional cytotoxic drugs without prolonged interruptions, the primary treatment target shifts from the tumor cell population to the tumor vasculature. This "metronomic" way of chemotherapy administration results in antivascular effects, the mechanistic basis of which remains to be fully elucidated. We outline the basic aspects of the metronomic concept, describe the results of clinical applications of such chemotherapy by focusing on studies in metastatic prostate cancer, and discuss certain shortcomings. Based on preclinical findings, we finally point to the possible ways to address these shortcomings in order to bring this novel and promising use of conventional anticancer agents to full fruition.
Recent results in cancer research. Fortschritte der Krebsforschung. Progrès dans les recherches sur le cancer 01/2010; 180:165-83.
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ABSTRACT: The cyclic administration of conventional (i.e., maximum tolerated dose [MTD]) chemotherapy targets primarily the tumor cell
population. In contrast, chemotherapeutics used at lower doses but on a more frequent basis, and without treatment-free breaks,
preferentially affect the tumor vasculature. This so-called low-dose metronomic (LDM) form of chemotherapy administration
can be considered as a complementary and/or alternative form of antiangiogenic therapy to the use of targeted antiangiogenic
agents such as antibodies or small molecule drugs that interfere with vascular endothelial growth factor (VEGF) pathways.
However, it becomes increasingly clear that LDM chemotherapy affects also aspects of the tumor microenvironment other than
angiogenesis such as immune responses. Herein, we summarize the complex effects of LDM chemotherapy on the tumor microenvironment,
with special emphasis on angiogenesis. We also compare the effects of LDM versus MTD chemotherapy. Finally, we outline how
pharmacogenetic characteristics of the tumor host and microenvironment may be exploited in the future to predict response
to LDM therapy.
KeywordsLow-dose metronomic chemotheray-Maximum tolerated dose chemotherapy-Antiangiogenesis-Immunomodulation-Pharmacogenetics
12/2009: pages 243-262;
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Nan Soon Wong,
Robert A Buckman,
Mark Clemons,
Shailendra Verma,
Susan Dent,
Maureen E Trudeau,
Kathie Roche,
John Ebos,
Robert Kerbel,
Gerrit E Deboer,
Donald J A Sutherland, Urban Emmenegger,
Joyce Slingerland,
Sandra Gardner,
Kathleen I Pritchard
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ABSTRACT: PURPOSE Preclinical studies indicate that metronomic chemotherapy is antiangiogenic and synergistic with other antiangiogenic agents. We designed a phase I/II study to evaluate the safety and activity of adding dalteparin and prednisone to metronomic cyclophosphamide and methotrexate in women with measurable metastatic breast cancer (MBC). PATIENTS AND METHODS Patients received daily dalteparin and oral cyclophosphamide, twice-weekly methotrexate, and daily prednisone (dalCMP). The primary study end point was clinical benefit rate (CBR), a combination of complete response (CR), partial response (PR), and prolonged stable disease for > or = 24 weeks (pSD). Secondary end points included time to progression (TTP), duration of response, and overall survival (OS). Biomarker response to treatment was assessed by using plasma vascular endothelial growth factor (VEGF) and soluble VEGF receptors (sVEGFRs) -1 and -2. Results Forty-one eligible patients were accrued. Sixteen (39%) had no prior chemotherapy for MBC; 15 (37%) had two or more chemotherapy regimens for MBC. Toxicities were minimal except for transient grade 3 elevation of liver transaminases in 11 patients (27%) and grade 3 vomiting in one patient (2%). One patient (2%) had CR, six (15%) had PR, and three (7%) had pSD, for a CBR of 10 (24%) of 41 patients. Median TTP was 10 weeks (95% CI, 8 to 17 weeks), and median OS was 48 weeks (95% CI, 32 to 79 weeks). VEGF levels decreased but not significantly, whereas sVEGFR-1 and -2 levels increased significantly after 2 weeks of therapy. There was no correlation between response and VEGF, sVEGFR-1, or sVEGFR-2 levels. CONCLUSION Metronomic dalCMP is safe, well tolerated, and clinically active in MBC.
Journal of Clinical Oncology 12/2009; 28(5):723-30. · 18.37 Impact Factor
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Canadian Urological Association journal = Journal de l'Association des urologues du Canada 10/2009; 3(5):375-6. · 1.24 Impact Factor
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ABSTRACT: Metronomic chemotherapy is a minimally toxic and frequently effective new treatment strategy that is beginning to show promising phase II clinical trial results, particularly for metastatic breast cancer when combined with various molecularly targeted antitumor agents. Here, we assessed a treatment strategy that uses trastuzumab plus daily oral metronomic cyclophosphamide on metastatic Her-2-positive human breast cancer models.
Treatments were initiated on orthotopic transplanted primary tumors as well as established visceral metastatic disease of two independent Her-2-positive breast cancer models, both independently derived from the human MDA-MB-231 breast cancer cell line. Outcome was assessed by noninvasive measurements of tumor cell-secreted human choriogonadotropin in the urine as a surrogate marker of relative tumor burden, or by whole body bioluminescent imaging, in addition to prolongation of survival.
Orthotopic primary tumors responded to trastuzumab monotherapy with significant growth delays, whereas minimal antitumor effect was observed when mice with metastatic disease were treated. Nevertheless, trastuzumab showed a benefit in this latter setting when combined with metronomic low-dose cyclophosphamide as assessed by prolongation of survival. This benefit was similar to trastuzumab plus maximum tolerated dose cyclophosphamide, but was associated with lesser toxicity.
Trastuzumab combined with metronomic cyclophosphamide may be an effective long-term maintenance strategy for the treatment of Her-2-positive metastatic breast cancer.
Clinical Cancer Research 10/2009; 15(20):6358-66. · 7.74 Impact Factor
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Anna Fioravanti,
Bastianina Canu,
Greta Alì,
Paola Orlandi,
Giacomo Allegrini,
Teresa Di Desidero, Urban Emmenegger,
Gabriella Fontanini,
Romano Danesi,
Mario Del Tacca,
Alfredo Falcone,
Guido Bocci
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ABSTRACT: Metronomic chemotherapy (the frequent, long term, low dose administration of chemotherapeutic drugs) is a promising therapy because it enhances the anti-endothelial activity of conventional chemotherapeutics, but with lower or no toxic effects compared to maximum tolerated dose administration. The aims of the present study were to compare, in vitro and in vivo, the antiangiogenic and antitumor activities of metronomic irinotecan (CPT-11), oxaliplatin (L-OHP) and 5-fluorouracil (5-FU) in colorectal cancer and to investigate the metronomic combination of these drugs. In vitro cell proliferation, combination studies and vascular endothelial growth factor (VEGF) secretion analyses were performed on endothelial (HMVEC-d) and colorectal cancer (HT-29) cells exposed for 144 h to metronomic concentrations of SN-38, the active metabolite of CPT-11, L-OHP and 5-FU. HT-29 human colorectal cancer xenograft model was used and tumour growth, microvessel density and VEGF quantification were performed in tumours after the administration of metronomic CPT-11, L-OHP, 5-FU and their simultaneous combination. Low concentrations of SN-38, but not 5-FU and L-OHP, preferentially inhibited endothelial cell proliferation. Simultaneous and continuous exposure of HT-29 and HMVEC-d cells to low concentrations SN-38+L-OHP+5-FU for 144 h showed a strong antagonism and an unfavorable dose-reduction index. Moreover, the ternary combination resulted in a significant increase of VEGF secretion in HT-29 cancer cells. In a xenograft model metronomic CPT-11, but not 5-FU and L-OHP, significantly inhibits HT-29 tumor growth and microvessel density in the absence of toxicity. On the contrary, metronomic 5-FU+L-OHP+CPT-11 therapy did not affect the microvascular count. The metronomic concept might not universally apply to every cytotoxic drug in colorectal cancer and metronomic combination regimens should be used with caution.
European journal of pharmacology 09/2009; 619(1-3):8-14. · 2.59 Impact Factor
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ABSTRACT: While targeting VEGF has shown success against a number of human cancers, drug resistance has resulted in compromised clinical benefits. In this issue of Cancer Cell, Crawford et al. (2009) report that tumors resistant to anti-VEGF therapy stimulate tumor-associated fibroblasts to express proangiogenic PDGF-C, implicating it as a potential therapeutic target.
Cancer cell 02/2009; 15(1):3-5. · 25.29 Impact Factor
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Yuval Shaked,
Erik Henke,
Jeanine M L Roodhart,
Patrizia Mancuso,
Marlies H G Langenberg,
Marco Colleoni,
Laura G Daenen,
Shan Man,
Ping Xu, Urban Emmenegger,
Terence Tang,
Zhenping Zhu,
Larry Witte,
Robert M Strieter,
Francesco Bertolini,
Emile E Voest,
Robert Benezra,
Robert S Kerbel
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ABSTRACT: Several hypotheses have been proposed to explain how antiangiogenic drugs enhance the treatment efficacy of cytotoxic chemotherapy, including impairing the ability of chemotherapy-responsive tumors to regrow after therapy. With respect to the latter, we show that certain chemotherapy drugs, e.g., paclitaxel, can rapidly induce proangiogenic bone marrow-derived circulating endothelial progenitor (CEP) mobilization and subsequent tumor homing, whereas others, e.g., gemcitabine, do not. Acute CEP mobilization was mediated, at least in part, by systemic induction of SDF-1alpha and could be prevented by various procedures such as treatment with anti-VEGFR2 blocking antibodies or paclitaxel treatment in CEP-deficient Id mutant mice, both of which resulted in enhanced antitumor effects mediated by paclitaxel, but not by gemcitabine.
Cancer cell 10/2008; 14(3):263-73. · 25.29 Impact Factor
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Giulio Francia, Urban Emmenegger,
Christina R Lee,
Yuval Shaked,
Christopher Folkins,
Miriam Mossoba,
Jeffrey A Medin,
Shan Man,
Zhenping Zhu,
Larry Witte,
Robert S Kerbel
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ABSTRACT: Historically, the use of mouse models of metastatic disease to evaluate anticancer therapies has been hampered because of difficulties in detection and quantification of such lesions without sacrificing the mice, which in turn may also be dictated by institutional or ethical guidelines. Advancements in imaging technologies have begun to change this situation. A new method to non-invasively measure tumor burden, as yet untested to monitor spontaneous metastases, is the use of transplanted tumors expressing secretable human beta-chorionic gonadotropin (beta-hCG) that can be measured in urine. We describe examples of beta-hCG-transfected tumor cell lines for evaluating the effect of different therapies on metastatic disease, which in some cases involved monitoring tumor growth for >100 days. We used beta-hCG-tagged mouse B16 melanoma and erbB-2/Her-2-expressing human breast cancer MDA-MB-231 models, and drug treatments included metronomic low-dose cyclophosphamide chemotherapy with or without a vascular endothelial growth factor receptor 2-targeting antibody (DC101) or trastuzumab, the erbB-2/Her-2-targeting antibody. Both experimental and spontaneous metastasis models were studied; in the latter case, an increase in urine beta-hCG always foreshadowed the development of lung, liver, brain, and kidney metastases. Metastatic disease was unresponsive to DC101 or trastuzumab monotherapy treatment, as assessed by beta-hCG levels. Our results also suggest that beta-hCG levels may be set as an end point for metastasis studies, circumventing guidelines, which have often hampered the use of advanced disease models. Collectively, our data indicates that beta-hCG is an effective noninvasive preclinical marker for the long term monitoring of untreated or treated metastatic disease.
Molecular Cancer Therapeutics 10/2008; 7(10):3452-9. · 5.23 Impact Factor
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Onkologie 01/2008; 30(12):606-8. · 0.87 Impact Factor
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12/2007: pages 63-80;
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Urban Emmenegger,
Yuval Shaked,
Shan Man,
Guido Bocci,
Ivan Spasojevic,
Giulio Francia,
Andrew Kouri,
Robert Coke,
William Cruz-Munoz,
Susan M Ludeman,
O Michael Colvin,
Robert S Kerbel
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ABSTRACT: Prolonged, frequently administered low-dose metronomic chemotherapy (LDM) is being explored (pre)clinically as a promising antiangiogenic antitumor strategy. Although appealing because of a favorable side effect profile and mostly oral dosing, LDM involves new challenges different from conventional maximum tolerated dose chemotherapy. These include possible altered pharmacokinetic characteristics due to long-term drug exposure potentially resulting in acquired resistance and increased risk of unfavorable drug interactions. We therefore compared the antitumor and antivascular effects of LDM cyclophosphamide (CPA) given to mice that had been pretreated with either LDM CPA or normal saline, obtained blood 4-hydroxy-CPA (activated CPA) concentrations using either gas chromatography/mass spectrometry or liquid chromatography/tandem mass spectrometry in mice treated with LDM CPA, and measured hepatic and intratumoral activity of enzymes involved in the biotransformation of CPA and many other drugs [i.e., cytochrome P450 3A4 (CYP3A4) and aldehyde dehydrogenase]. Exposure of mice to LDM CPA for >or=8 weeks did not compromise subsequent activity of LDM CPA therapy, and biologically active 4-hydroxy-CPA levels were maintained during long-term LDM CPA administration. Whereas the effects on CYP3A4 were complex, aldehyde dehydrogenase activity was not affected. In summary, our findings suggest that acquired resistance to LDM CPA is unlikely accounted for by altered CPA biotransformation. In the absence of reliable pharmacodynamic surrogate markers, pharmacokinetic parameters might become helpful to individualize/optimize LDM CPA therapy. LDM CPA-associated changes of CYP3A4 activity point to a potential risk of unfavorable drug interactions when compounds that are metabolized by CYP3A4 are coadministered with LDM CPA.
Molecular Cancer Therapeutics 08/2007; 6(8):2280-9. · 5.23 Impact Factor
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Journal of Clinical Oncology 09/2006; 24(24):4040; author reply 4040-1. · 18.37 Impact Factor
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ABSTRACT: Macrophage activating syndrome (MAS) is a rare hematological disorder associated with uncontrolled systemic T-cell activation. Persistent fever, fatigue and hepatosplenomegaly are frequent clinical manifestations, whereas hyperferritinemia, elevated serum lactate dehydrogenase levels and cytopenia are key criteria for the diagnosis of MAS. The nature of liver pathology in MAS has been partially elucidated but destructive biliary lesions have been rarely described. This report illustrates four cases of MAS developing marked cholestasis, leading to one case of biliary cirrhosis necessitating liver transplantation. Histologically, liver involvement was characterized in all cases by acute lobular hepatitis, marked hepatocyte apoptosis and small bile duct injury similar to the vanishing bile duct syndrome. Immuno-histological studies showed that the inflammatory changes and bile duct lesions were dominated by the presence of activated macrophages and T-cells, in particular CD8+ lymphocytes, and in part NK-cells. These findings suggest that in MAS, various T-cell triggers such as infection, autoimmune disease and malignancy might result in the release of cytokines, which in turn activate macrophages to trigger a systemic acute phase response and local tissue damage. This communication suggests that a macrophage, T- and NK-cell network is operational in the pathogenesis of the cholangiocyte, hepatocyte and sinus endothelial cell damage in MAS.
Journal of Hepatology 07/2006; 44(6):1208-12. · 9.26 Impact Factor
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ABSTRACT: Because antiangiogenic therapies inhibit the growth of new tumor-associated blood vessels, as well as prune newly formed vasculature, they would be expected to reduce the supply of oxygen and thus increase tumor hypoxia. However, it is not clear if antiangiogenic treatments lead only to consistent and sustained increases in hypoxia, or transient decreases in tumor hypoxia along with periods of increased hypoxia. We undertook a detailed analysis of an orthotopically transplanted human breast carcinoma (MDA-MB-231) over a 3-week treatment period using DC101, an anti-vascular endothelial growth factor receptor 2 antibody. We observed consistent reductions in microvascular density, blood flow (measured by high-frequency micro-ultrasound), and perfusion. These effects resulted in an increase in the hypoxic tumor fraction, measured with an exogenous marker, pimonidazole, concurrent with an elevation in hypoxia-inducible factor-1alpha expression, an endogenous marker. The increase in tumor hypoxia was evident within 5 days and remained so throughout the entire course of treatment. Vascular perfusion and flow were impaired at days 2, 5, 7, 8, 14, and 21 after the first injection, but not at 4 hours. A modest increase in the vessel maturation index was detected after the 3-week treatment period, but this was not accompanied by an improvement in vascular function. These results suggest that sustained hypoxia and impairment of vascular function can be two consistent consequences of antiangiogenic drug treatment. The implications of the results are discussed, particularly with respect to how they relate to different theories for the counterintuitive chemosensitizing effects of antiangiogenic drugs, even when hypoxia is increased.
Cancer Research 05/2006; 66(7):3639-48. · 7.86 Impact Factor
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ABSTRACT: Acquired resistance to trastuzumab (Herceptin) is common in patients whose breast cancers show an initial response to the drug. The basis of this acquired resistance is unknown, hampering strategies to delay or treat such acquired resistance, due in part to the relative lack of appropriate in vivo tumorigenic models.
We derived an erbB-2-positive variant called 231-H2N, obtained by gene transfection from the highly tumorigenic erbB-2/HER2-negative human breast cancer cell line, MDA-MB-231. Unlike MDA-MB-231, the 231-H2N variants was sensitive to trastuzumab both in vitro and especially in vivo, thus allowing selection of variant resistant to drug treatment in the latter situation after showing an initial response.
The growth of established orthotopic tumors in severe combined immunodeficient mice was blocked for 1 month by trastuzumab, after which rapid growth resumed. These relapsing tumors were found to maintain resistance to trastuzumab, both in vitro and in vivo. We evaluated various therapeutic strategies for two purposes: (a) to delay such tumor relapses or (b) to treat acquired trastuzumab resistance once it has occurred. With respect to the former, a daily oral low-dose metronomic cyclophosphamide regimen was found to be particularly effective. With respect to the latter, an anti-epidermal growth factor receptor antibody (cetuximab) was effective as was the anti-vascular endothelial growth factor (anti-VEGF) antibody bevacizumab, which was likely related to elevated levels of VEGF detected in trastuzumab-resistant tumors.
Our results provide a possible additional rationale for combined biological therapy using drugs that target both erbB-2/HER2 and VEGF and also suggest the potential value of combining less toxic metronomic chemotherapy regimens not only with targeted antiangiogenic agents but also with other types of drug such as trastuzumab.
Clinical Cancer Research 03/2006; 12(3 Pt 1):904-16. · 7.74 Impact Factor
