Search

Extra copies of centrosomes are frequently observed in cancer cells. To survive and proliferate, cancer cells have developed strategies to cluster extra-centrosomes to form bipolar mitotic spindles. The aim of this study was to investigate whether centrosome clustering (CC) inhibition (CCi) would preferentially radiosensitize non–small cell lung cancer (NSCLC). Griseofulvin (GF; FDA-approved treatment) inhibits CC, and combined with radiation treatment (RT), resulted in a significant increase in the number of NSCLC cells with multipolar spindles, and decreased cell viability and colony formation ability in vitro. In vivo, GF treatment was well tolerated by mice, and the combined therapy of GF and radiation treatment resulted in a significant tumor growth delay. Both GF and radiation treatment also induced the generation of micronuclei (MN) in vitro and in vivo and activated cyclic GMP-AMP synthase (cGAS) in NSCLC cells. A significant increase in downstream cGAS-STING pathway activation was seen after combination treatment in A549 radioresistant cells that was dependent on cGAS. In conclusion, GF increased radiation treatment efficacy in lung cancer preclinical models in vitro and in vivo. This effect may be associated with the generation of MN and the activation of cGAS. These data suggest that the combination therapy of CCi, radiation treatment, and immunotherapy could be a promising strategy to treat NSCLC.

Figure S1 shows basal centrosome amplification in cell lines. Figure S2 shows the effect of GF on cell viability. Figure S3 shows HSET expression in cell lines. Figure S4 shows the effect of GF on clonogenic potential after RT. Figure S5 shows the induction of micronuclei after GF and/or RT. Figure S6 shows the expression of IFN-β after GF and/or RT.

Extra copies of centrosomes are frequently observed in cancer cells. To survive and proliferate, cancer cells have developed strategies to cluster extra-centrosomes to form bipolar mitotic spindles. The aim of this study was to investigate whether centrosome clustering (CC) inhibition (CCi) would preferentially radiosensitize non–small cell lung cancer (NSCLC). Griseofulvin (GF; FDA-approved treatment) inhibits CC, and combined with radiation treatment (RT), resulted in a significant increase in the number of NSCLC cells with multipolar spindles, and decreased cell viability and colony formation ability in vitro. In vivo, GF treatment was well tolerated by mice, and the combined therapy of GF and radiation treatment resulted in a significant tumor growth delay. Both GF and radiation treatment also induced the generation of micronuclei (MN) in vitro and in vivo and activated cyclic GMP-AMP synthase (cGAS) in NSCLC cells. A significant increase in downstream cGAS-STING pathway activation was seen after combination treatment in A549 radioresistant cells that was dependent on cGAS. In conclusion, GF increased radiation treatment efficacy in lung cancer preclinical models in vitro and in vivo. This effect may be associated with the generation of MN and the activation of cGAS. These data suggest that the combination therapy of CCi, radiation treatment, and immunotherapy could be a promising strategy to treat NSCLC.

Supplementary Materials & Methods

This document contains supplemental details such as antibodies and primers, list of genes overrepresented in TWIST1 and TWIST1 mutants, IHC staining for TWIST1 in mouse prostate development, IHC staining for TWIST1 and HOXA9 in various mouse models of prostate cancer, correlation of TWIST1 and HOXA9 alteration with poor survival in human prostate cancer patients, IHC for TWIST1 and HOXA9 on primary tumors and bone metastasis from prostate cancer patients, IHC for HOXA9 on cell pellets expressing HOXA9 or control and on adult mouse prostate, data showing sufficiency of HOXA9 for some pro-metastatic behaviour in prostate cancer cells, data showing requirement of WDR5 and HOTTIP for TWIST1-dependent pro-metastatic behavior, ChIP data showing binding of TWIST1 and HOXA9 at the HOXA9 promoter, data showing effect of drugs that can inhibit HOXA9 on prostate cancer cell viability and pro metastatic behaviour.

TWIST1 is a transcription factor critical for development that can promote prostate cancer metastasis. During embryonic development, TWIST1 and HOXA9 are coexpressed in mouse prostate and then silenced postnatally. Here we report that TWIST1 and HOXA9 coexpression are reactivated in mouse and human primary prostate tumors and are further enriched in human metastases, correlating with survival. TWIST1 formed a complex with WDR5 and the lncRNA Hottip/HOTTIP, members of the MLL/COMPASS–like H3K4 methylases, which regulate chromatin in the Hox/HOX cluster during development. TWIST1 overexpression led to coenrichment of TWIST1 and WDR5 as well as increased H3K4me3 chromatin at the Hoxa9/HOXA9 promoter, which was dependent on WDR5. Expression of WDR5 and Hottip/HOTTIP was also required for TWIST1-induced upregulation of HOXA9 and aggressive cellular phenotypes such as invasion and migration. Pharmacologic inhibition of HOXA9 prevented TWIST1-induced aggressive prostate cancer cellular phenotypes in vitro and metastasis in vivo. This study demonstrates a novel mechanism by which TWIST1 regulates chromatin and gene expression by cooperating with the COMPASS-like complex to increase H3K4 trimethylation at target gene promoters. Our findings highlight a TWIST1–HOXA9 embryonic prostate developmental program that is reactivated during prostate cancer metastasis and is therapeutically targetable. Cancer Res; 77(12); 3181–93. ©2017 AACR.

This document contains experimental details for microarray data acquisition and analysis, immunohistochemistry, immunofluorescence, western blotting, migration assay, invasion assay, anoikis assay, soft agar colony formation assay, RNA-immunoprecipitation, protein co-immunoprecipitation, Chromatin immunoprecipitation (ChIP), ChIP-Re-ChIP.

Patients with EGFR-mutant non-small-cell lung cancer (NSCLC) have significantly benefited from the use of EGFR tyrosine kinase inhibitors (TKIs). However, long-term efficacy of these therapies is limited due to de novo resistance (~30%) as well as acquired resistance. Epithelial–mesenchymal transition transcription factors (EMT-TFs), have been identified as drivers of EMT-mediated resistance to EGFR TKIs, however, strategies to target EMT-TFs are lacking. As the third generation EGFR TKI, osimertinib, has now been adopted in the first-line setting, the frequency of T790M mutations will significantly decrease in the acquired resistance setting. Previously less common mechanisms of acquired resistance to first generation EGFR TKIs including EMT are now being observed at an increased frequency after osimertinib. Importantly, there are no other FDA approved targeted therapies after progression on osimertinib. Here, we investigated a novel strategy to overcome EGFR TKI resistance through targeting the EMT-TF, TWIST1, in EGFR-mutant NSCLC. We demonstrated that genetic silencing of TWIST1 or treatment with the TWIST1 inhibitor, harmine, resulted in growth inhibition and apoptosis in EGFR-mutant NSCLC. TWIST1 overexpression resulted in erlotinib and osimertinib resistance in EGFR-mutant NSCLC cells. Conversely, genetic and pharmacological inhibition of TWIST1 in EGFR TKI-resistant EGFR-mutant cells increased sensitivity to EGFR TKIs. TWIST1-mediated EGFR TKI resistance was due in part to TWIST1 suppression of transcription of the pro-apoptotic BH3-only gene, BCL2L11 (BIM), by directly binding to BCL2L11 intronic regions and promoter. As such, pan-BCL2 inhibitor treatment overcame TWIST1-mediated EGFR TKI resistance and were more effective in the setting of TWIST1 overexpression. Finally, in a mouse model of autochthonous EGFR-mutant lung cancer, Twist1 overexpression resulted in erlotinib resistance and suppression of erlotinib-induced apoptosis. These studies establish TWIST1 as a driver of resistance to EGFR TKIs and provide rationale for use of TWIST1 inhibitors or BCL2 inhibitors as means to overcome EMT-mediated resistance to EGFR TKIs.

// Mustafa A. Barbhuiya 1, * , Adam C. Mirando 2, * , Brian W. Simons 3 , Ghali Lemtiri-Chlieh 1 , Jordan J. Green 2 , Aleksander S. Popel 2 , Niranjan B. Pandey 2 and Phuoc T. Tran 1, 3 1 Department of Radiation Oncology and Molecular and Radiation Sciences, Sidney Kimmel Comprehensive Cancer Centre, Johns Hopkins School of Medicine, Baltimore, MD, USA 2 Department of Biomedical Engineering, Johns Hopkins University School of Medicine, Baltimore, MD, USA 3 Department of Medical Oncology, Sidney Kimmel Comprehensive Cancer Centre and Department of Urology, The Brady Urological Institute, Johns Hopkins University School of Medicine, Baltimore, MD, USA * These authors have contributed equally to this work Correspondence to: Phuoc T. Tran, email: tranp@jhmi.edu , tranpt21@sbcglobal.net Niranjan B. Pandey, email: npandey4@jhmi.edu , npandey@asclepix.com Aleksander S. Popel, email: apopel@jhu.edu Keywords: hepatocellular carcinoma; angiogenesis; c-Met; HGF; IGF1R Received: April 07, 2017 Accepted: August 26, 2017 Published: September 21, 2017 ABSTRACT Hepatocellular carcinoma (HCC) is a major cause of cancer-related death worldwide. Due to inadequate screening methods and the common coexistence of limited functional liver reserves, curative treatment options are limited. Liver transplantation is the only curative treatment modality for early HCC. There are multidisciplinary treatment options like ablative treatments, radiation and systemic therapy available for more advanced patients or those that are inoperable. Treatment resistance and progression is inevitable for these HCC patients. Newer therapeutics need to be explored for better management of HCC. HCC is a hypervascular tumor and many pro-angiogenic proteins are found significantly overexpressed in HCC. Here we explored the therapeutic potential of the anti-angiogenic, anti-lymphangiogenic, and directly anti-tumorigenic biomimetic collagen IV-derived peptide developed by our group. Human HCC cell lines HuH7, Hep3b and HepG2 showed significant disruption of cell adhesion and migration upon treatment with the peptide. Consistent with previously described multimodal inhibitory properties, the peptide was found to inhibit both c-Met and IGF1R signaling in HepG2 cells and blocked HepG2 conditioned media stimulation of microvascular endothelial cell (MEC) tube formation. Furthermore, the peptide treatment of mouse HepG2 tumor xenografts significantly inhibited growth relative to untreated controls. The peptide was also found to improve the survival of autochthonous Myc-induced HCC in a transgenic mouse model. Mechanistically, we found that the peptide treatment reduced microvascular density in the autochthonous liver tumors with increased apoptosis. This study shows the promising therapeutic potential of our biomimetic peptide in the treatment of HCC.

TWIST1 is a transcription factor critical for development that can promote prostate cancer metastasis. During embryonic development, TWIST1 and HOXA9 are coexpressed in mouse prostate and then silenced postnatally. Here we report that TWIST1 and HOXA9 coexpression are reactivated in mouse and human primary prostate tumors and are further enriched in human metastases, correlating with survival. TWIST1 formed a complex with WDR5 and the lncRNA Hottip/HOTTIP, members of the MLL/COMPASS–like H3K4 methylases, which regulate chromatin in the Hox/HOX cluster during development. TWIST1 overexpression led to coenrichment of TWIST1 and WDR5 as well as increased H3K4me3 chromatin at the Hoxa9/HOXA9 promoter, which was dependent on WDR5. Expression of WDR5 and Hottip/HOTTIP was also required for TWIST1-induced upregulation of HOXA9 and aggressive cellular phenotypes such as invasion and migration. Pharmacologic inhibition of HOXA9 prevented TWIST1-induced aggressive prostate cancer cellular phenotypes in vitro and metastasis in vivo. This study demonstrates a novel mechanism by which TWIST1 regulates chromatin and gene expression by cooperating with the COMPASS-like complex to increase H3K4 trimethylation at target gene promoters. Our findings highlight a TWIST1–HOXA9 embryonic prostate developmental program that is reactivated during prostate cancer metastasis and is therapeutically targetable. Cancer Res; 77(12); 3181–93. ©2017 AACR.

TWIST1 is a transcription factor critical for development which can promote prostate cancer metastasis. During embryonic development, TWIST1 and HOXA9 are co-expressed in mouse prostate and then silenced post-natally. Here we report that TWIST1 and HOXA9 co-expression are re-activated in mouse and human primary prostate tumors and are further enriched in human metastases, correlating with survival. TWIST1 formed a complex with WDR5 and the lncRNA Hottip/HOTTIP, members of the MLL/COMPASS-like H3K4 methylases, which regulate chromatin in the Hox/HOX cluster during development. TWIST1 overexpression led to co-enrichment of TWIST1 and WDR5 as well increased H3K4me3 chromatin at the Hoxa9/HOXA9 promoter which was dependent on WDR5. Expression of WDR5 and Hottip/HOTTIP was also required for TWIST1-induced upregulation of HOXA9 and aggressive cellular phenotypes such as invasion and migration. Pharmacological inhibition of HOXA9 prevented TWIST1-induced aggressive prostate cancer cellular phenotypes in vitro and metastasis in vivo. This study demonstrates a novel mechanism by which TWIST1 regulates chromatin and gene expression by cooperating with the COMPASS-like complex to increase H3K4 trimethylation at target gene promoters. Our findings highlight a TWIST1-HOXA9 embryonic prostate developmental program that is reactivated during prostate cancer metastasis and is therapeutically targetable.

The centrosome is a microtubule-organizing center that plays an important role during M-phase and cell division where it organizes the two poles of the bipolar microtubule spindle apparatus from which chromosomes are segregated. In contrast to most normal cells, the vast majority of lung cancers contain extra copies of centrosomes, and a large body of circumstantial evidence links extra centrosomes to the development of cancer. Cells with supernumerary centrosomes form multipolar mitotic spindles, which, if not corrected, lead to lethal multipolar divisions or “mitotic catastrophe.” To overcome this, lung cancer cells cluster their centrosomes into two spindle poles, enabling tumor cells to survive. Thus, inhibition of centrosome clustering (CCi) can force cancer cells into multipolar divisions, lead to chromosomal instability, make cancer cells more sensitive to radiation treatment, and eventually result in the selective killing of cancer cells. At the same time, this approach should spare healthy tissues with normal centrosome numbers, resulting in a favorable therapeutic index. To examine the relationship between CCi and radiation-treatment sensitivity, we first treated three NSCLC cell lines (A549, H460 and H358) and one immortalized primary human bronchial epithelial cell (HBEC) with griseofulvin—a centrosomal clustering inhibitor. Immunofluorescent staining for pericentrin and alpha-tubulin, we observed a significant increase in the number of cells with multipolar spindles in NSCLC cells compared to HBECs (40-80% vs. 15%). Next, we examined the ability of griseofulvin to radiosensitize these cells to radiation treatment. By using clonogenic assays, we saw significantly less clonogenic potential of NSCLC cells following radiation treatment after exposure to 30 uM of griseofulvin, but griseofulvin did not radiosensitize HBECs. To further confirm our results, we genetically targeted KIFC1, a member of kinesin-14 family of motor proteins that have been shown to be essential for clustering centrosomes in cancer cells, but are not required for division in normal cells. In our experiments, knockdown of KIFC1 expression with siRNA also significantly sensitized NSCLC cells to radiation treatment. Finally, when we treated the NSCLC cells with griseofulvin, we saw a significant increase in the formation of micronuclei in cancer cells. Recently, it has been shown that micronuclei are important sources of immunostimulatory DNA via activation of the cGAS-STING pathway. Therefore, inhibition of CC could potentially augment immunogenicity and increase efficiency of immunotherapy (IMT). In conclusion, inhibition of CC resulted in the formation of multipolar spindle in NSCLCs and further sensitized NSCLCs to radiation treatment. CC is not typically required for normal cells, and thus CCi may be a more specific and perhaps less toxic therapy for NSCLCs. The potential of CCi to enhance IMT is under investigation. Citation Format: Hailun Wang, Katriana Nugent, Matthew Ballew, Ghali Lemtiri-Chlieh, Natasha Raman, Michelle Levine, Andrew Holland, Phuoc Tran. Centrosome clustering inhibition as a novel strategy to sensitize non-small cell lung cancer to radiation treatment and immunotherapy [abstract]. In: Proceedings of the Fifth AACR-IASLC International Joint Conference: Lung Cancer Translational Science from the Bench to the Clinic; Jan 8-11, 2018; San Diego, CA. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(17_Suppl):Abstract nr B12.

Hepatocellular carcinoma (HCC) related mortality ranks second worldwide and stands one step behind lung cancer. Due to the asymptomatic nature of the cancer, early diagnosis is a major problem. Currently only liver transplantation is curative for early stage hepatocellular cancer. There are other multidisciplinary treatment options like radiation and chemotherapy available for advanced patients. However, chemotherapy resistance is a common problem in the treatment of liver cancer. Newer therapeutics are needed for better management of advanced HCC. Angiogenesis and lymphangiogenesis are processes that are vital for tumorigenesis and metastasis. HCC is known to be a hypervascular tumor and many pro-angiogenic proteins are found significantly overexpressed in HCC. We explored the therapeutic potential of the anti-angiogenic and anti-lymphangiogenic, biomimetic peptide SP2043 developed by our group in HCC. Hepatocellular carcinoma cell lines HuH-7, Hep3b and HepG2 showed significant disruption of cell adhesion and migration following treatment. Furthermore, SP2043 was found to impair microvascular endothelial cell (MEC) tube formation induced by HepG2 tumor conditioned media and to significantly inhibit HepG2 tumor xenograft growth compared to untreated controls. The peptide drug was also found to improve the survival of autochthonous Myc induced HCC in a transgenic mouse model from two weeks to four weeks. We discovered the peptide to be a multi-modal anti-angiogenic drug that also inhibits IGF1R and MET signaling pathways in HCC cell lines. We also found that SP2043 treatment reduced the microvascular density in both subcutaneous and autochthonous liver tumors with reduced tumor cell proliferation and increased apoptosis. This study shows the therapeutic potential of SP2043 in the treatment of hepatocellular carcinoma. Note: This abstract was not presented at the meeting. Citation Format: Mustafa A. Barbhuiya, Adam C. Mirando, Brian W. Simons, Ghali Lemtiri-Chlieh, Jordan J. Green, Aleksander S. Popel, Niranjan B. Pandey, Phuoc T. Tran. Therapeutic potential of anti-angiogenic multimodal biomimetic peptide in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3201. doi:10.1158/1538-7445.AM2017-3201