Hyun-Ji Jang

Targeting the insulin-like growth factor receptor and Src signaling network for the treatment of non-small cell lung cancer

BackgroundTherapeutic interventions in the insulin-like growth factor receptor (IGF-1R) pathway were expected to provide clinical benefits; however, IGF-1R tyrosine kinase inhibitors (TKIs) have shown limited antitumor efficacy, and the mechanisms conveying resistance to these agents remain elusive.MethodsThe expression and activation of the IGF-1R and Src were assessed via the analysis of a publicly available dataset, as well as immunohistochemistry, Western blotting, RT-PCR, and in vitro kinase assays. The efficacy of IGF-1R TKIs alone or in combination with Src inhibitors was analyzed using MTT assays, colony formation assays, flow cytometric analysis, and xenograft tumor models.ResultsThe co-activation of IGF-1R and Src was observed in multiple human NSCLC cell lines as well as in a tissue microarray (n = 353). The IGF-1R and Src proteins mutually phosphorylate on their autophosphorylation sites. In high-pSrc-expressing NSCLC cells, linsitinib treatment initially inactivated the IGF-1R pathway but led a Src-dependent reactivation of downstream effectors. In low-pSrc-expressing NSCLC cells, linsitinib treatment decreased the turnover of the IGF-1R and Src proteins, ultimately amplifying the reciprocal co-activation of IGF-1R and Src. Co-targeting IGF-1R and Src significantly suppressed the proliferation and tumor growth of both high-pSrc-expressing and low-pSrc-expressing NSCLC cells in vitro and in vivo and the growth of patient-derived tissues in vivo.ConclusionsReciprocal activation between Src and IGF-1R occurs in NSCLC. Src causes IGF-1R TKI resistance by acting as a key downstream modulator of the cross-talk between multiple membrane receptors. Targeting Src is a clinically applicable strategy to overcome resistance to IGF-1R TKIs.

Smoking-associated lung cancer prevention by blockade of the beta-adrenergic receptor-mediated insulin-like growth factor receptor activation

Activation of receptor tyrosine kinases (RTKs) is associated with carcinogenesis, but its contribution to smoking-associated lung carcinogenesis is poorly understood. Here we show that a tobacco-specific carcinogen 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK)-induced insulin-like growth factor 1 receptor (IGF-1R) activation via β-adrenergic receptor (β-AR) is crucial for smoking-associated lung carcinogenesis. Treatment with NNK stimulated the IGF-1R signaling pathway in a time- and dose-dependent manner, which was suppressed by pharmacological or genomic blockade of β-AR and the downstream signaling including a Gβγ subunit of β-AR and phospholipase C (PLC). Consistently, β-AR agonists led to increased IGF-1R phosphorylation. The increase in IGF2 transcription via β-AR, signal transducer and activator of transcription 3 (STAT3), and nuclear factor-kappa B (NF-κB) was associated with NNK-induced IGF-1R activation. Finally, treatment with β-AR antagonists suppressed the acquisition of transformed phenotypes in lung epithelial cells and lung tumor formation in mice. These results suggest that blocking β-AR-mediated IGF-1R activation can be an effective strategy for lung cancer prevention in smokers.

Chronic Stress Facilitates Lung Tumorigenesis by Promoting Exocytosis of IGF2 in Lung Epithelial Cells

Molecular insights into how chronic stress affects lung tumorigenesis may offer new routes to chemoprevention. In this study, we show that chronic stress in mice chemically or genetically initiated for lung cancer leads to the release of norepinephrine and other catecholamines, thereby promoting lung tumorigenesis. Mechanistically, norepinephrine induced phosphorylation of L-type voltage-dependent calcium channels (VDCC) through the β-adrenergic receptor-PKA pathway. VDCC triggered calcium mobilization, thereby inducing activation of IGF-1R via exocytosis of insulin-like growth factor 2 (IGF2). Mice expressing lung-specific IGF-1R exhibited accelerated lung tumor development in response to chronic stress. Notably, clinically approved antihypertensive drugs that block L-type VDCC prevented the effects of chronic stress or norepinephrine on the IGF2/IGF-1R signaling cascade, along with transformation of lung epithelial cells and lung tumor formation. Overall, our results identify an actionable mechanism to limit the effects of chronic stress on lung tumorigenesis. Cancer Res; 76(22); 6607-19. ©2016 AACR.

Abstract 2711: Regulation of the IGF-1R signaling by angiotensin signaling pathway

Lung cancer is one of the most commonly diagnosed cancers in the world. Tobacco smoking is the most predominant risk factor for the development of lung cancer. Carcinogenic compounds in tobacco smoke are thought to be responsible for lung cancer, at least in part, by activating G-protein coupled receptor (GPCR)-mediated signaling pathways. GPCR signaling has been suggested to cross-talk with the IGF-1R signaling pathway, a key pathway for cell survival, transformation and growth. However, the mechanisms underlying the crosstalk between GPCR and IGF-1R signaling pathways remain poorly understood. Here we show that tobacco carcinogen (TC) contributes to the lung carcinogenesis by activating the angiotensin signaling and subsequent IGF-1R signaling pathways. We observed that a potent tobacco carcinogen, nitrosamine 4-(methylnitro-samino)-1-(3-pyridyl)-1-butanone (NNK, nicotine-derived nitrosamine ketone), induced transformed phenotypes, including foci formation, viability in the absence of growth factors, and anchorage-dependent and -independent colony formation, and activation of the IGF-1R in normal human bronchial epithelial cells. The NNK treatment also induced lung tumor formation in mice. Losartan, an angiotensin type-1 receptor blocker, and captopril, an angiotensin converting enzyme (ACE) inhibitor, disrupted NNK-induced IGF-1R activation and transformed phenotypes in normal human bronchial epithelial cells and reduced lung tumor formation in mice. These findings indicated that TC-induced angiotensin signaling pathway can enhance lung carcinogenesis by activating the IGF-1R signaling. Our results suggest that targeting IGF-1R by using angiotensin signaling inhibitors may be an effective strategy for the chemoprevention of lung cancer. Citation Format: Hye-Jin Boo, Hyun-Ji Jang, Yujin Jung, Hye-Young Min, Ho-Young Lee. Regulation of the IGF-1R signaling by angiotensin signaling pathway. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2711. doi:10.1158/1538-7445.AM2015-2711

Abstract 2729: Chronic stress promotes lung cancer development via IGF-1R pathway

Lung cancer is a leading cause of cancer death worldwide. Although smoking is a main cause, approximately 25% of lung cancer cases are not attributable to tobacco use. Epidemiological studies strongly suggest that chronic stress influences cancer development and progression. Recent mechanistic studies showed that biological signaling pathways could contribute to such effects. But the underlying mechanisms for the association between chronic stress and lung cancer development are poorly understood. The purpose of this study is to investigate whether chronic stress can induce lung cancer development and, if so, what is the mechanism underlying the chronic stress-induced lung cancer development. We observed that stress hormone, norepinephrine (NE) increased cell viability in the absence of growth factors, foci formation, and colony formation in human bronchial epithelial cells and activated the type 1 insulin-like growth factor receptor (IGF-1R) pathway. We found that chronic stress resulted in high levels of NE in serum, activation of IGF-1R in lung tissue and promoted urethane-induced lung tumor formation in vivo. Moreover, inhibition of the IGF-1R pathway suppressed NE-induced transformed phenotypes in vitro. We further confirmed that chronic stress-induced lung tumor formation was greater in mice carrying lung-specific human IGF-1R transgene (Tg) than in wild type mice. Our results indicate that chronic stress may promote lung cancer development via the IGF-1R pathway, suggesting that IGF-1R is an effective target for the chemoprevention of stress-induced lung cancer. Citation Format: Hyun-Ji Jang, Hye-Jin Boo, Yujin Jung, Hye-Young Min, Ho-Young Lee. Chronic stress promotes lung cancer development via IGF-1R pathway. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2729. doi:10.1158/1538-7445.AM2015-2729

Abstract 1716: Targeting the insulin-like growth factor receptor/Insulin receptor and Src signaling network for the treatment of non-small cell lung cancer

Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Insulin-like growth factor I receptor (IGF-1R)-mediated signaling plays an important role in the proliferation, survival, and metastasis of cancer cells. The IGF-1R-targeting anticancer agents including monoclonal antibodies and small molecule tyrosine kinase inhibitors (TKIs) have been developed, but their antitumor effects have been marginal and limited in clinical trials. Therefore, the mechanism underlying resistance to the IGF-1R-targeting therapies and the rational combination strategies to overcome potential drug resistance need to be investigated. In this study, we demonstrated the association of Src with the resistance to the IGF-1R TKI in non-small cell lung cancer (NSCLC). We found the co-activation of IGF-1R/IR and Src in various human NSCLC cell lines, The mRNA expression and phosphorylation of IGF-1R and Src were also significantly correlated with each other in NSCLC databases from a public dataset and a tissue microarray (n=353). Next, we found Src can be activated through multiple pathways including EGFR and integrin β3 signaling and function as an alternative kinase for phosphorylation of IGF-1R, especially at Tyr1135/36, but not Tyr1131. Src is activated in lung cancer cells possessing both primary and acquired resistance to an IGF-1R TKI. Consistent with the results, inhibition of Src significantly attenuated activation of IGF-1R/IR and co-targeting of IGF-1R and Src effectively suppressed cell proliferation, colony formation, and tumor growth in vitro and in vivo. Taken together, these results suggest that Src causes resistance to IGF-1R TKIs by functioning as a key downstream modulator of multiple signaling pathways for IGF-1R phosphorylation and thus co-targeting IGF-1R and Src could be an effective therapeutic strategy for NSCLC. Citation Format: Hye-Young Min, Hye Jeong Yun, Hyo-Jong Lee, Jaebeom Cho, Hyun-Ji Jang, Kyung Min Kim, Woo-Young Kim, Seung-Hyun Oh, Diane Liu, J. Jack Lee, Waun Ki Hong, Ignacio I. Wistuba, Ho-Young Lee. Targeting the insulin-like growth factor receptor/Insulin receptor and Src signaling network for the treatment of non-small cell lung cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1716. doi:10.1158/1538-7445.AM2014-1716

Abstract 5638: Preclinical evidence supporting cotargeting insulin-like growth factor receptor (IGF-1R) and Src in non-small cell lung cancer.

The antitumor efficacy of IGF-1R targeting agents (TKIs or antibodies) has been evaluated in recent clinical trials, but the effect has been found to be marginal and limited. Since it has been suggested that IGF-1R and Src signaling pathways cooperate with each other in the proliferation and survival of cancer cells, we investigated the role of Src in the resistance to the IGF-1R TKI and further suggested the rationale of co-targeting of IGF-1R and Src in the treatment of NSCLC. We examined Src-mediated regulation of IGF-1R activation and assessed the effect of the combined treatment with an IGF-1R TKI and a Src inhibitor on the proliferation, survival, and signaling changes in human NSCLC cells and NSCLC xenografts in nude mice. In addition, expressions of the IGF-1R signaling axis were evaluated in tissue microarrays of NSCLC from two independent databases (N=352, and 353, respectively) and correlated with clinicopathologic characteristics and patient survival. We found co-activation of IGF-1R and Src in various NSCLC cells and modulation of IGF-1R signaling by overexpression or knockdown of Src. Combined blockade of IGF-1R and Src resulted in the suppression of cell proliferation, induction of apoptosis, inhibition of signaling responsible for cell survival and proliferation, and tumor growth in vivo. In human tissue samples, p-IGF-1R/IR, IGF-1R, and pSrc expressions were significantly associated with squamous cell carcinoma (SCC) in both TMAs. pIGF-1R/IR and pSrc had strong positive correlation with each other (P Citation Format: Jin-Soo Kim, Hye-Young Min, Hye Jeong Yun, Hyun-Ji Jang, Edward S. Kim, Diane Liu, J. Jack Lee, Carmen Behrens, Scott M. Lippman, Waun Ki Hong, Ignacio I. Wistuba, Ho-Young Lee. Preclinical evidence supporting cotargeting insulin-like growth factor receptor (IGF-1R) and Src in non-small cell lung cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5638. doi:10.1158/1538-7445.AM2013-5638