Cancer Letters

Cancer Letters

Volume 417, 28 March 2018, Pages 168-173
Cancer Letters

Original Articles
Recombinant methioninase in combination with doxorubicin (DOX) overcomes first-line DOX resistance in a patient-derived orthotopic xenograft nude-mouse model of undifferentiated spindle-cell sarcoma

https://doi.org/10.1016/j.canlet.2017.12.028Get rights and content

Highlights

  • Established the PDOX model of undifferentiated spindle-cell sarcoma (USCS).

  • The USCS PDOX model is resistant to first-line therapy doxorubicin (DOX).

  • Recombinant methioninase (rMETase) overcame the DOX resistance of the USCS PDOX.

Abstract

We have previously established a patient-derived orthotopic xenograft (PDOX) model of undifferentiated spindle cell sarcoma (USCS). Recombinant methioninase (rMETase) has previously demonstrated efficacy in PDOX mouse models of human cancers. In the present study, we determined if rMETase in combination with doxorubicin (DOX) can overcome first-line DOX resistance in a PDOX models of USCS. The USCS PDOX mouse models were randomized into the following groups when tumor volume reached 100 mm3: G1, control without treatment; G2, doxorubicin (DOX) (3 mg/kg, intraperitoneal [i.p.] injection, weekly, for 2 weeks); G3, rMETase (100 units/mouse, i.p., daily, for 2 weeks); G4, DOX (3 mg/kg, i.p., weekly, for 2 weeks) combined with rMETase (100 units/mouse, i.p., daily, for 2 weeks). Tumor size and body weight were measured twice a week. On day 14 after initiation, the USCS PDOX tumor sizes were (G1): 360 ± 85 mm3; DOX (G2): 355 ± 111 mm3, p = .927; rMETase (G3): 182 ± 57 mm3, p = .0003; DOX + rMETase (G4): 134 ± 29 mm3, p = .00001. These results indicate that rMETase can overcome USCS resistance to DOX, which is first line therapy for this disease. The body weight of treated mice was not significantly different in any group. The present results demonstrate the power of the PDOX model to identify effective therapy for recalcitrant cancer and the potential of rMETase to overcome DOX resistance.

Introduction

Undifferentiated spindle-cell sarcoma (USCS) is a recalcitrant cancer with predominant spindle-shaped cells that originates in the nerve sheath, connective tissue under the skin, in muscles, and other organs and are fibromyxoid with mesenchymal and neuroendocrine differentiation [1]. USCS of the thyroid gland [2], chest wall [3], and lung with metastasis to bone have also been described [4].

We previously established a patient-derived orthotopic xenograft (PDOX) nude mouse model of USCS with the technique of surgical orthotopic implantation (SOI) in the right biceps femoris muscle [5]. We initially evaluated the efficacy of standard first-line chemotherapy of doxorubicin (DOX), gemcitabine (GEM) combined with docetaxel (DOC), compared to pazopanib (PAZ), a multi-targeting tyrosine-kinase inhibitor, which had the greatest efficacy in the USCS PDOX model. These recent results demonstrated that the PDOX model of USCS could identify a promising novel agent with significantly greater efficacy than first-line therapy [5].

PAZ is a synthetic indazolylpyrimidine that is an inhibitor of multiple tyrosine kinases [6]. A phase III clinical trial for metastatic STS has been carried out to evaluate the efficacy of PAZ. A significant 3-month advantage in progression-free survival (PFS) was achieved by PAZ [7], which is consistent with our previously results in the PDOX model. However, it is impotant to discover more effective therapy for USCS.

Methionine dependence is due to the overuse of methionine for aberrant transmethylation reactions in cancer and is possibly the only known general metabolic defect in cancer [[8], [9], [10], [11], [12], [13], [14]].

The overuse of methionine by cancer cells for enhanced and unbalanced transmethylation may be the basis of the methionine dependence of cancer cells and is termed the “Hoffman effect”, analogous to Warburg effect of flucose overuse in cancer [12].

In order to target methionine dependence for therapy, our laboratory previously cloned l-methionine α-deamino-γ-mercaptomethane lyase [EC 4.4.1.11]) [15]. The cloned methioninase, termed recombinant methioninase, or rMETase, has been tested in mouse models of human cancer cell lines [[16], [17], [18], [19]]. rMETase effectively reduced tumor growth of a DOX-resistant Ewing's sarcoma PDOX compared to untreated control. The methionine level both of plasma and supernatants derived from sonicated tumors was lower in the rMETase group [20].

In a PDOX models of BRAF V600E mutant melanoma, first-line temozolomide (TEM) and rMETase was significantly more efficacious than either mono-therapy [21].

In the present study, we show that rMETase can overcome first-line DOX resistance in the PDOX models of USCS.

Section snippets

Mice

Athymic nu/nu nude mice (AntiCancer Inc., San Diego, CA), 4–6 weeks old, were used in this study. Animals were housed in a barrier facility on a high efficiency particulate arrestance (HEPA)-filtered rack under standard conditions of 12-h light/dark cycles. The animals were fed an autoclaved laboratory rodent diet. All animal studies were conducted in accordance with the principles and procedures outlined in the National Institute of Health Guide for the Care and Use of Animals under Assurance

Efficacy testing of first line therapy DOX on the USCS PDOX

To test the efficacy of first line therapy DOX on the USCS PDOX, we injected DOX weekly for 2 weeks. We found that the USCS PDOX was highly resistant to DOX with a tumor volume of 355 +/- 110 mm3 at 14 days compared to the control of 360 ± 85, p = .927 (Fig. 2, Fig. 3).

Efficacy of testing rMETase on the USCS PDOX

To test the efficacy rMETase on the USCS PDOX, we injected rMETase daily for 2 weeks. We found that rMETase alone inhibited the USCS PDOX growth with a tumor volume of 182 ± 57 mm, p = .0003 (Fig. 2, Fig. 3).

Efficacy testing of the combination of rMETase and DOX on the USCS PDOX

To test the efficacy

Discussion

The present study demonstrates the power of the PDOX model to identify effective therapy for recalcitrant cancer in this case USCS. A critical finding of the current study was that rMETase treatment could overcome first-line DOX resistance in the USCS PDOX model.

Toward this goal of precision, personalized oncology, our laboratory pioneered the patient-derived orthotopic xenograft (PDOX) nude mouse model with the technique of surgical orthotopic implantation (SOI), including pancreatic [[22],

Conclusions

In the present study of DOX-resistant USCS PDOX model, it was found that rMETase in combination with DOX could overcome DOX resistance. The present study further emphasizes the power of the PDOX model to distinguish therapies. The other critical observation of the present study is that rMEtase can overcome first-line-therapy DOX resistance, suggesting a future clinical strategy for this recalcitrant disease, especially since previous studies have shown minimal toxicity of rMETase and

Conflicts of interest

The authors declare that they have no competing interests.

Acknowledgements

This manuscript is dedicated to the memory of Dr. A.R. Moossa, Dr. Sun Lee and Dr. Shigeo Yagi.

References (50)

  • R.M. Hoffman et al.

    High in vivo rates of methionine biosynthesis in transformed human and malignant rat cells auxotrophic for methionine

    Proc. Natl. Acad. Sci. U. S. A.

    (1976)
  • P.H. Stern et al.

    Reduced free-methionine in methionine-dependent SV40-transformed human fibroblasts synthesizing apparently normal amounts of methionine

    J Cell. Physiol.

    (1983)
  • P.S. Stern et al.

    Altered methionine metabolism occurs in all members of a set of diverse human tumor cell lines

    J. Cell. Physiol.

    (1984)
  • P.H. Stern et al.

    Elevated overall rates of transmethylation in cell lines from diverse human tumors

    In Vitro

    (1984)
  • D.W. Coalson et al.

    Reduced availability of endogenously synthesized methionine for S-adenosylmethionine formation in methionine dependent cancer cells

    Proc. Natl. Acad. Sci. U. S. A.

    (1982)
  • H. Guo et al.

    Therapeutic tumor-specific cell cycle block induced by methionine starvation in vivo

    Cancer Res.

    (1993)
  • R.M. Hoffman et al.

    Reversible growth arrest in simian virus 40-transformed human fibroblasts

    Proc. Natl. Acad. Sci. U. S. A.

    (1980)
  • D.M. Kokkinakis et al.

    Regulation of O6-methylguanine-DNA methyltransferase by methionine in human tumour cells

    Br. J. Cancer

    (1997)
  • D.M. Kokkinakis et al.

    Effect of long-term depletion of plasma methionine on the growth and survival of human brain tumor xenografts in athymic mice

    Nutr. Cancer

    (1997)
  • T. Murakami et al.

    Recombinant methioninase effectively targets a Ewing's sarcoma in a patient-derived orthotopic xenograft (PDOX) nude-mouse model

    Oncotarget

    (2017)
  • K. Kawaguchi et al.

    Combination treatment with recombinant methioninase enables temozolomide to arrest a BRAF V600E melanoma growth in a patient-derived orthotopic xenograft

    Oncotarget

    (2017)
  • Y. Hiroshima et al.

    Efficacy of tumor-targeting Salmonella typhimurium A1-R in combination with anti-angiogenesis therapy on a pancreatic cancer patient-derived orthotopic xenograph (PDOX) and cell line mouse models

    Oncotarget

    (2014)
  • X. Fu et al.

    A metastatic nude-mouse model of human pancreatic cancer constructed orthotopically with histologically intact patient specimens

    Proc. Natl. Acad. Sci. U. S. A.

    (1992)
  • Y. Hiroshima et al.

    Metastatic recurrence in a pancreatic cancer patient derived orthotopic xenograft (PDOX) nude mouse model is inhibited by neoadjuvant chemotherapy in combination with fluorescence-guided surgery with an anti-CA 19–9-conjugated fluorophore

    PLos One

    (2014)
  • Y. Hiroshima et al.

    Selective efficacy of zoledronic acid on metastasis in a patient-derived orthotopic xenograph (PDOX) nude-mouse model of human pancreatic cancer

    J. Surg. Oncol.

    (2015)
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