ALK Tyrosine Kinase Inhibitors in Drug Sensitization

ALK Tyrosine Kinase Inhibitors in Drug Sensitization

C H A P T E R 4 ALK Tyrosine Kinase Inhibitors in Drug Sensitization Tong Wu*,†, Liwu Fu* * State Key Laboratory of Oncology in South China, Collabo...

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C H A P T E R

4 ALK Tyrosine Kinase Inhibitors in Drug Sensitization Tong Wu*,†, Liwu Fu* *

State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangdong Esophageal Cancer Institute, Sun Yat-Sen University Cancer Center, Guangzhou, China † Department of Oral Medicine, Guanghua School of Stomatology, Guangdong Provincial Key Laboratory of Stomatology, Sun Yat-Sen University, Guangzhou, China

Abstract Since the genomic aberrations of anaplastic lymphoma kinase (ALK) promote cancer cell proliferation and survival, specific tyrosine kinase inhibitors (TKIs) targeting these molecules have been developed. Besides its original targeting ALK effect, several studies have reported that ALK inhibitors can modulate the ATP-binding cassette (ABC) transporter to reverse the multiple drug resistance (MDR), which is one of the major obstacles for the successful cancer chemotherapy. In this chapter, we highlight reports manifesting that ALK inhibitors, including crizotinib, ceritinib, alectinib, and lorlatinib to antagonize ABC transporters to re-sensitize the anticancer drug in vitro and in vivo. These results give us some hints that specific ALK TKIs in combination with conventional anticancer drugs may be a good strategy to overcome the MDR in the clinic.

Abbreviations ABC

ATP-binding cassette

ADP ALCL ALK ASCO DOX EML-4 FDA IRS1 MAPK MDR

adenosine diphosphate anaplastic large-cell non-Hodgkin’s lymphoma anaplastic lymphoma kinase American Society of Clinical Oncology doxorubicin echinoderm microtubule-associated protein-like 4 Food and Drug Administration insulin receptor substrate 1 mitogen-activated protein kinase multiple drug resistance

Protein Kinase Inhibitors as Sensitizing Agents for Chemotherapy https://doi.org/10.1016/B978-0-12-816435-8.00004-3

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# 2019 Elsevier Inc. All rights reserved.

46 MK NCCN NSCLC PFS PI3K PTN Rho 123 TKIs

4. ALK TYROSINE KINASE INHIBITORS IN DRUG SENSITIZATION

midkine National Comprehensive Cancer Network nonsmall cell lung cancer progression-free survival phosphoinositide 3-kinase pleiotrophin Rhodamine 123 tyrosine kinase inhibitors

Conflict of Interest No potential conflicts of interest were disclosed.

INTRODUCTION In 1994, a new protein anaplastic lymphoma kinase (ALK), which was encoded by fusion of the nucleophosmin gene located on 5q35 to a protein tyrosine kinase gene located on 2p23 in anaplastic large-cell non-Hodgkin’s lymphoma (ALCL), was first reported [1]. According to the Cancer Genome Atlas data, the ALK gene transforming rearrangements, mutation, and amplification have been discovered in cancers from 17 organs, including anaplastic large-cell lymphoma, papillary thyroid carcinoma, neuroblastoma, ovarian cancer, head and neck cancer, as well as nonsmall-cell lung cancer (NSCLC) [2]. Since the recognition of the oncogene ALK, specific tyrosine kinase inhibitors (TKIs) targeting these molecules have been developed, which significantly improved the response rates and progression-free survivals (PFS) of patients with metastatic NSCLC harboring ALK rearrangement [3]. Furthermore, ALK is only expressed in a few adult tissues; as a result little side effects might be expected from therapy antagonizing ALK function. Currently several ALK TKIs, including crizotinib, ceritinib, alectinib, lorlatinib, and brigatinib, have been approved by the Food and Drug Administration (FDA) for first- or second-line treatment in metastatic NSCLC patients with ALK rearrangement. Other ALK TKIs such as brigatinib, lorlatinib, entrectinib, and ensartinib are in different phases of clinical trials (Table 1). Besides its original targeting ALK effect, several studies have reported that these ALK inhibitors can modulate the ATP-binding cassette (ABC) transporter to reverse the multiple drug resistance (MDR) [4, 5].

ALK SIGNALING PATHWAY ALK, located on chromosome 2p23, is mainly expressed in the brain, where it is thought to play a fundamental role in the development and function of the nervous system. Besides, ALKs are also expressed in small intestine and testis but not normal lymphoid tissue in physiological conditions [6]. ALK is a receptor tyrosine kinase of the insulin receptor superfamily, whose constitutive activation is primarily induced by point mutations and gene rearrangements. ALK translocation most frequently involved in the gene encoding echinoderm microtubule-associated protein-like 4 (EML-4) [7, 8]. Through pleiotrophin (PTN) and midkine (MK) binding to the ALK receptor, several downstream signaling pathways

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ALK TKIs IN REVERSING MULTIDRUG RESISTANCE

TABLE 1

The Effect of Reported ALK TKIs on the Modulating ABC Transporters

Agent

ALK Target IC50 (nM)

Crizotinib

24

Ceritinib

Company

Status

Year

ABC Transporter Inhibited

ROS1, cMET

Pfizer

FDA approved in ALK+ NSCLC patients

2011

ABCB1

Yes

0.2

ROS1, IGF-R1

Novartis

FDA approved in ALK+ metastatic NSCLC in patients that failed treatment with crizotinib

2014

ABCB1, ABCG2

Yes

Alectinib

1–3.5

RET

Roche

FDA approved in ALK+ NSCLC patients whose disease worsened after, or who could not tolerate, treatment with crizotinib

2015

ABCB1, ABCG2

No

Lorlatinib

0.07–0.2

ROS1

Pfizer

FDA approved in ALK+ metastatic NSCLC

2015

ABCB1

No

Brigatinib

0.62

EGFR

ARIAD

FDA approved as a 2nd-line therapy for ALK-positive metastatic NSCLC

2017

No data

No data

Other Targets

Substrate of ABC Transporter

are activated [9, 10]. PTN activates the mitogen-activated protein kinase (MAPK) pathway, while MK induces insulin receptor substrate 1 (IRS1) phosphorylation, activating both the MAPK and phosphoinositide 3-kinase (PI3K) pathways [11–14]. It is believed that the genomic aberrations of ALK promote cancer cell proliferation, survival, angiogenesis, and migration through its downstream signaling pathway cascade activation, including the MAPK, JAK/STAT, and PI3K/AKT pathways (Fig. 1) [15]. According to the Cancer Genome Atlas data, the ALK gene transforming rearrangements, mutation, and amplification have been discovered in anaplastic large-cell lymphoma, papillary thyroid carcinoma, neuroblastoma, ovarian cancer, head and neck cancer, as well as NSCLC [2]. This evidence suggests that ALK may be a driving force in the development or progression of these tumors.

ALK TKIs IN REVERSING MULTIDRUG RESISTANCE MDR refers to the resistant of cancer cells to a broad variety of structurally and mechanistically different anticancer drugs, which is one of the principle barriers in successful cancer chemotherapy [4]. ABC transporter-mediated active translocation of a series of mechanistically and structurally diverse agents crossing cell membranes is believed to be one of the principle causes of MDR, which leads to the failure of cancer chemotherapy. These transporters efflux various substrates across the membrane against a concentration gradient by energy derived from ATP hydrolysis to adenosine diphosphate (ADP) [4, 5]. Among these transporters, ABCB1, ABCC1, and ABCG2 are the most widely studied transporters in MDR. Ever since the discovery of the significant role of overexpression of ABC transporters in cancer cells

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4. ALK TYROSINE KINASE INHIBITORS IN DRUG SENSITIZATION

PTN/MK ALK

JAKS

STAT

P

P

P

P

JNK

RAS

PI3K

JUN

RAF

AKT

AP-1

MEK1/2

mTOR

ERK1/2

Angiogenesis, migration, proliferation

FIG. 1 Anaplastic lymphoma kinase (ALK) signaling pathway. Through PTN, MK binding, ALK phosphorylation activate downstream signaling cascades including MAPK/ERK, PI3K/AKT, and STAT3 pathways, which leading to the increment of cancer cell proliferation, angiogenesis, and metastasis.

mediating MDR, tireless efforts have been devoted to drug exploitation which could antagonize or inactivate these transporters to overcome the resistance to anticancer drugs. In the last decade, besides the traditional MDR modulators, a number of small molecule kinase inhibitors which were originally designed for targeting other cell-signal network molecule have been found to interact with ABC transporters [4]. Several ALK TKIs have been reported to inhibit the pumping function of ABC transporters and re-sensitize the anticancer drug (Table 1).

CRIZOTINIB Crizotinib is an orally available small molecule TKI of the ALK, c-MET, and ROS1, which competitively binds to the ATP-binding pocket of target kinases to inhibit ALK phosphorylation, and it downstream signal transduction, which leads to G1/S phase cell cycle arrest and apoptosis [16–19]. It was approved in an accelerated manner by the US FDA for the therapy of late-stage NSCLC harboring EML4-ALK translocation on August 26, 2011 [20]. For its effectiveness against ALK-positive lung cancer, crizotinib now is recognized by the National Comprehensive Cancer Network (NCCN) and American Society of Clinical Oncology (ASCO) as the standard care for ALK-positive NSCLC patients. The effect of crizotinib on

CERITINIB

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reversing MDR has been reported. Zhou et al. found that crizotinib was an inhibitor and transported substrate of ABCB1 in vitro. Through enhancing the ATPase activity of ABCB1 in a concentration-dependent manner, crizotinib significantly inhibited the efflux and increased the intracellular accumulation of traditional anticancer drug in ABCB1-overexpressing MDR cells at low concentrations [21]. These results postulate that crizotinib can be repositioned as a chemosensitizer in combination with conventional anticancer agents to overcome the MDR and to enhance their therapeutic efficacy. However, when crizotinib was applied on advanced NSCLC chemotherapy, the therapeutic efficacy is decreased for ABCB1 pump effluxion. Tang et al. found that after oral administration of a medium dose of crizotinib (5 mg/kg), in ABCB1 knockout mice the plasma concentration of crizotinib was approximately threefold of that in wild-type mice. This result indicates that oral absorption and/or systemic clearance of crizotinib was involved in ABCB1. Furthermore, while crizotinib was given at a high oral dose of 50 mg/kg, the absence of Abcb1a/1b in knockout mice had no effect on the oral availability of crizotinib, but the brain accumulation of crizotinib was still profoundly increased. When oral crizotinib (5 mg/kg) was administered with ABCB1 inhibitor elacridar simultaneously, through which ABCB1 was fully and specifically inhibited, crizotinib levels in brain were highly upregulated and oral availability increased about twofold in wild-type mice [22]. Collectively, these data demonstrated that crizotinib is a good transport substrate of ABCB1, and thus potentially a competitive inhibitor for other ABCB1 substrates as well. Crizotinib with other ABCB1 inhibitors may perhaps be considered to effectively improve crizotinib delivery and ultimately leading to a more favorable therapeutic efficacy in ALKpositive NSCLC patients.

CERITINIB Due to the emerging problem such as the resistance and toxicity of crizotinib, a series of second-generation ALK inhibitors have been developed. Ceritinib (LDK378) is the secondgeneration ALK inhibitors approved by the US FDA in 2014 for the therapy of ALK-positive metastatic NSCLC in patients who failed treatments with crizotinib [23]. Hu et al. found that through acting as a competitive inhibitor of ABCB1 and ABCG2, ceritinib significantly inhibited ABCB1- or ABCG2-mediated drug efflux to increase the intracellular chemotherapeutic agents’ accumulation without effecting the ABC pump protein expression in the transporters-overexpressing cells [24]. These results advocate the ceritinib administration in combination with other conventional chemotherapeutic drugs in chemo-refractory cancer patients. Similar to crizotinib, ceritinib is the substrate of ABCB1 and ABCG2; this property of ceritinib is the obstacle of its clinical use in metastatic NSCLC patients with ABCB1 or ABCG2 expression. Kort et al. [25] demonstrated that ceritinib is transported efficiently by ABCB1 and ABCG2 transporters which strongly restricted the ceritinib brain penetration. ABCB1 overexpression was identified in 3 out of 11 cases with crizotinib- or ceritinib-resistant NSCLC patients harboring ALK rearrangement. The overexpression of ABCB1 is an underlying resistance mechanism of ceritinib in ALK-rearranged NSCLC patients. Because the ABCB1 transporter pumps ceritinib outside of cancer cells, knocked or inhibition of the function of ABCB1 effectively re-sensitized the patient-derived cancer cell to ceritinib, in vitro and in vivo [26].

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4. ALK TYROSINE KINASE INHIBITORS IN DRUG SENSITIZATION

ALECTINIB Alectinib (CH5424802/RO5424802) is a potent, more selective, and an orally administered ALK inhibitor with 10-fold potency greater than crizotinib. Besides its activity against ALK harboring mutations C1156Y, L1196 M, and F1174 L, it also possesses activities against kinases including RET proto-oncogene rearrangements, cyclin G-associated kinase (GAK), as well as leukocyte receptor tyrosine kinase [27]. Preliminary data indicated that alectinib attains an overall response rate of 55.4% in NSCLC patients with ALK rearrangement, which is similar to crizotinib or ceritinib [28]. Alectinib was first approved for the treatment of ALK fusiongene positive unresectable, advanced, or recurrent NSCLC in Japan in July 2014 [29]. Soon afterwards, alectinib was also approved by the US FDA in December 2015 to treat patients with advanced ALK-positive NSCLC whose disease worsened after, or who could not tolerate, treatment with crizotinib. The reversal effect of alectinib on MDR induced by ABC transporters has been reported. Yang et al. found that through inhibiting the efflux function of the ABCB1, ABCG2 transporters, alectinib increases the intracellular accumulation of ABCB1, ABCG2 substrates such as Rhodamine 123 (Rho 123) and doxorubicin (DOX) to reverse the resistance of the ABCB1- and ABCG2-overexpressing cells to chemotherapeutic agents, without effecting ABCB1/ABCG2 protein expression [30]. However, ABCB1 overexpression cells showed significant resistance to ceritinib and crizotinib but not to alectinib, which indicates that alectinib is not the substrate of ABCB1 and suggests that the combination of alectinib with ceritinib or crizotinib could overcome the resistance mediated by ABCB1 overexpression [26].

LORLATINIB Lorlatinib (PF-06463922) is a highly potent orally administered small molecule inhibitor of ALK and ROS1 [31]. For its strong activity against all known ALK and ROS1 mutants identified in patients resisting to crizotinib, US FDA granted lorlatinib, the orphan drug status for the treatment of NSCLC patients in 2015. Katayama et al. found that lorlatinib was able to reverse the ABCB1-mediating ceritinib resistance, suggesting that lorlatinib can act as an MDR inhibitor but not the substrate of ABCB1 [26].

PERSPECTIVE One of the principle obstacle hindering the successful cancer chemotherapy is MDR. It is well recognized that ABC transporters’ mediated efflux is a significant mechanism underlying MDR. For its importance, effects have been devoted to develop nontoxic agents that inhibit the transporting function of ABC pumps which can be used in combination with conventional chemotherapeutic drugs to increase their efficacy. However, up today, the FDA has not approved any ABC transporter inhibitors in combination with conventional chemotherapeutic drugs in clinical use due to their unpredictable side effects. It is nice to observe that in the last decade several studies have been designed to exploit the effects of agents that were neither originally used nor approved as MDR modulators; the small molecule TKI is

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REFERENCES ABCB1

Extracellular

ABCB1

Extracellular

Ceritinib ABCG2

ABCG2

Alcetinib Crizotinib

Anticancer drugs

ADP

ATP

ATP

P

AD P

ADP

ATP

Lorlatinib P AT

AD P

ATP

Anticancer drugs

Intracellular

(A)

P AD

AT P

ADP

ADP AT

ADP ATP

Intracellular

(B)

FIG. 2

Mechanism of ALK TKIs reversing MDR. In the absence of ALK TKIs, ABCB1 and ABCG2 transporters utilize energy derived from the hydrolysis of ATP to efflux their substrates across the membrane (A). However, in the presence of ALK TKIs, including crizotinib, ceritinib, alectinib, and lorlatinib, ALK TKIs may compete with the transporter substrates to interact with the substrate-binding sites of ABCB1 and ABCG2 to mediate the efflux downregulation and increase intracellular accumulation of the transporter substrates (B).

a case in point. Obviously, it would be promising to develop some agents that antagonize the ABC transporter to increase the intracellular accumulation of the conventional chemotherapeutic drugs, without producing additional pharmacological toxicity. In this chapter, we highlight investigations demonstrating that ALK inhibitors, including crizotinib, ceritinib, alectinib, and lorlatinib, blocked ABC transporters in vitro and in vivo (Fig. 2). The effect of other ALK TKIs or even other TKIs on ABC transports should be studied in the future. These results give us some hints that specific ALK TKIs in combination with conventional anticancer drugs may be a good strategy to overcome the MDR in clinic.

Acknowledgments This work was supported by grants from National Nature Scientific Foundation (No. 81473233), International Collaboration Science Research Foundation of Guangdong Province (No. 2013B051000046), and Medical Science and Technology Research Fund of Guangdong Province (No. B2013145).

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