Discovery of New Anti-Cancer Agents against Patient-Derived Sorafenib-Resistant Papillary Thyroid Cancer.

Thyroid cancer is the most well-known type of endocrine cancer that is easily treatable and can be completely cured in most cases. Nonetheless, anti-cancer drug-resistant metastasis or recurrence may occur and lead to the failure of cancer therapy, which eventually leads to the death of a patient with cancer. This study aimed to detect novel thyroid cancer target candidates based on validating and identifying one of many anti-cancer drug-resistant targets in patient-derived sorafenib-resistant papillary thyroid cancer (PTC). We focused on targeting the sarco/endoplasmic reticulum calcium ATPase (SERCA) in patient-derived sorafenib-resistant PTC cells compared with patient-derived sorafenib-sensitive PTC cells. We discovered novel SERCA inhibitors (candidates 33 and 36) by virtual screening. These candidates are novel SERCA inhibitors that lead to remarkable tumor shrinkage in a xenograft tumor model of sorafenib-resistant patient-derived PTC cells. These results are clinically valuable for the progression of novel combinatorial strategies that facultatively and efficiently target extremely malignant cancer cells, such as anti-cancer drug-resistant PTC cells.

Anti-Cancer SERCA Inhibitors Targeting Sorafenib-Resistant Human Papillary Thyroid Carcinoma.

Thyroid cancer is generally curable and, in many cases, can be completely treated, although it can sometimes recur after cancer therapy. Papillary thyroid cancer (PTC) is known as one of the most general subtypes of thyroid cancer, which take up nearly 80% of whole thyroid cancer. However, PTC may develop anti-cancer drug resistance via metastasis or recurrence, making it practically incurable. In this study, we propose a clinical approach that identifies novel candidates based on target identification and validation of numerous survival-involved genes in human sorafenib-sensitive and -resistant PTC. Consequently, we recognized a sarco/endoplasmic reticulum calcium ATPase (SERCA) in human sorafenib-resistant PTC cells. Based on the present results, we detected novel SERCA inhibitor candidates 24 and 31 via virtual screening. These SERCA inhibitors showed remarkable tumor shrinkage in the sorafenib-resistant human PTC xenograft tumor model. These consequences would be clinically worthwhile for the development of a new combinatorial strategy that effectively targets incredibly refractory cancer cells, such as cancer stem cells and anti-cancer drug-resistant cells.

PMCA inhibition reverses drug resistance in clinically refractory cancer patient-derived models.

BACKGROUND: Cancer cells have developed molecular strategies to cope with evolutionary stressors in the dynamic tumor microenvironment. Peroxisome proliferator-activated receptor-γ coactivator-1α (PGC1α) is a metabolic rheostat that regulates diverse cellular adaptive behaviors, including growth and survival. However, the mechanistic role of PGC1α in regulating cancer cell viability under metabolic and genotoxic stress remains elusive. METHODS: We investigated the PGC1α-mediated survival mechanisms in metabolic stress (i.e., glucose deprivation-induced metabolic stress condition)-resistant cancer cells. We established glucose deprivation-induced metabolic stress-resistant cells (selected cells) from parental tumor cells and silenced or overexpressed PGC1α in selected and parental tumor cells. RESULTS: Several in vitro and in vivo mouse experiments were conducted to elucidate the contribution of PGC1α to cell viability in metabolic stress conditions. Interestingly, in the mouse xenograft model of patient-derived drug-resistant cancer cells, each group treated with an anti-cancer drug alone showed no drastic effects, whereas a group that was co-administered an anti-cancer drug and a specific PMCA inhibitor (caloxin or candidate 13) showed marked tumor shrinkage. CONCLUSIONS: Our results suggest that PGC1α is a key regulator of anti-apoptosis in metabolic and genotoxic stress-resistant cells, inducing PMCA expression and allowing survival in glucose-deprived conditions. We have discovered a novel therapeutic target candidate that could be employed for the treatment of patients with refractory cancers.

Olfactomedin 4 produces dysplasia but suppresses metastasis of colon cancer.

Development of colorectal cancer (CRC) is regulated by a series of genetic and microenvironmental alterations. Olfactomedin 4 (OLFM4) is a secreted glycoprotein that is highly expressed in the gastrointestinal tract and modulates inflammation. However, the role of OLFM4 in CRC is uncertain. Here we aimed to explore the function of OLFM4 in CRC in vivo and in vitro. The mRNA expression of OLFM4 was up-regulated in precursor lesions with dysplasia or ulcerative colitis but was reduced in CRC. OLFM4 neutralizing antibody suppressed inflammation-mediated early-stage CRC formation in an AOM/DSS colitis-associated cancer model. OLFM4 knockdown cells exhibited increased cell proliferation and motility in vitro and in vivo. Ablation of OLFM4 increased tumor growth and metastasis in xenograft experiments. In addition, OLFM4 knockdown cells showed elevated expression of colon cancer stem cell markers including CD133, resulting in increased metastasis via epithelial-mesenchymal transition signaling. This study demonstrated that OLFM4 regulates inflammation and cancer progression differently; ablation of OLFM4 promotes cancer metastasis via stemness and epithelial-mesenchymal transition. These results suggest a new route for controlling cancer progression and metastasis.

Potential Therapeutic Agents against Paclitaxel-And Sorafenib-Resistant Papillary Thyroid Carcinoma.

Thyroid carcinoma, a disease in which malignant cells form in the thyroid tissue, is the most common endocrine carcinoma, with papillary thyroid carcinoma (PTC) accounting for nearly 80% of total thyroid carcinoma cases. However, the management of metastatic or recurrent therapy-refractory PTC is challenging and requires complex carcinoma therapy. In this study, we proposed a new clinical approach for the treatment of therapy-refractory PTC. We identified sarco/endoplasmic reticulum calcium ATPase (SERCA) as an essential factor for the survival of PTC cells refractory to the treatment with paclitaxel or sorafenib. We validated its use as a potential target for developing drugs against resistant PTC, by using patient-derived paclitaxel- or sorafenib-resistant PTC cells. We further discovered novel SERCA inhibitors, candidates 7 and 13, using the evolutionary chemical binding similarity method. These novel SERCA inhibitors determined a substantial reduction of tumors in a patient-derived xenograft tumor model developed using paclitaxel- or sorafenib-resistant PTC cells. These results could provide a basis for clinically meaningful progress in the treatment of refractory PTC by identifying a novel therapeutic strategy: using a combination therapy between sorafenib or paclitaxel and specific SERCA inhibitors for effectively and selectively targeting extremely malignant cells such as antineoplastic-resistant and carcinoma stem-like cells.

Discovery of Pharmaceutical Composition for Prevention and Treatment in Patient-Derived Metastatic Medullary Thyroid Carcinoma Model.

Medullary thyroid carcinoma (MTC) is a well-known neuroendocrine carcinoma, derived from C cells of the thyroid gland. Additionally, MTC is an uncommon aggressive carcinoma that metastasizes to lymph nodes, bones, lungs and liver. For MTC, the 10-year general survival ratio of patients with localized disease is about 95%, whereas that of patients with local phase disorder is around 75%. Only 20% of patients with distant metastasis to lung at diagnosis survive 10 years, which is notably lower than survival for well-differentiated thyroid carcinoma (WDTC). The management of MTC with distant metastasis to lung could be re-surgery or chemotherapy. In this research, we planned to assess the in vitro and in vivo combinational anticancer effect of a novel combination of low-dose cisplatin and sorafenib in patient-derived MTC. The patient-derived MTC cell lines YUMC-M1, M2, and M3 were isolated and treated with a combination of cisplatin and sorafenib or either agent alone. Cisplatin and sorafenib acted in combination to forward tumor restraint compared with each agent administered alone at a low dose. Therefore, a combination of cisplatin and sorafenib could be a new therapeutic approach for MTC.

Drug Discovery Using Evolutionary Similarities in Chemical Binding to Inhibit Patient-Derived Hepatocellular Carcinoma.

Drug resistance causes therapeutic failure in refractory cancer. Cancer drug resistance stems from various factors, such as patient heterogeneity and genetic alterations in somatic cancer cells, including those from identical tissues. Generally, resistance is intrinsic for cancers; however, cancer resistance becomes common owing to an increased drug treatment. Unfortunately, overcoming this issue is not yet possible. The present study aimed to evaluate a clinical approach using candidate compounds 19 and 23, which are sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA) inhibitors, discovered using the evolutionary chemical binding similarity method. mRNA sequencing indicated SERCA as the dominant marker of patient-derived anti-cancer drug-resistant hepatocellular carcinoma (HCC), but not of patient-derived anti-cancer drug-sensitive HCC. Candidate compounds 19 and 23 led to significant tumor shrinkage in a tumor xenograft model of anti-cancer drug-resistant patient-derived HCC cells. Our results might be clinically significant for the development of novel combinatorial strategies that selectively and efficiently target highly malignant cells such as drug-resistant and cancer stem-like cells.

Effects of Anti-Cancer Drug Sensitivity-Related Genetic Differences on Therapeutic Approaches in Refractory Papillary Thyroid Cancer.

Thyroid cancer (TC) includes tumors of follicular cells; it ranges from well differentiated TC (WDTC) with generally favorable prognosis to clinically aggressive poorly differentiated TC (PDTC) and undifferentiated TC (UTC). Papillary thyroid cancer (PTC) is a WDTC and the most common type of thyroid cancer that comprises almost 70-80% of all TC. PTC can present as a solid, cystic, or uneven mass that originates from normal thyroid tissue. Prognosis of PTC is excellent, with an overall 10-year survival rate >90%. However, more than 30% of patients with PTC advance to recurrence or metastasis despite anti-cancer therapy; consequently, systemic therapy is limited, which necessitates expansion of improved clinical approaches. We strived to elucidate genetic distinctions due to patient-derived anti-cancer drug-sensitive or -resistant PTC, which can support in progress novel therapies. Patients with histologically proven PTC were evaluated. PTC cells were gained from drug-sensitive and -resistant patients and were compared using mRNA-Seq. We aimed to assess the in vitro and in vivo synergistic anti-cancer effects of a novel combination therapy in patient-derived refractory PTC. This combination therapy acts synergistically to promote tumor suppression compared with either agent alone. Therefore, genetically altered combination therapy might be a novel therapeutic approach for refractory PTC.

Synergistic Anticancer Activity of N-Hydroxy-7-(2-Naphthylthio) Heptanomide, Sorafenib, and Radiation Therapy in Patient-Derived Anaplastic Thyroid Cancer Models.

Anaplastic thyroid cancer (ATC) is an undifferentiated and advanced form of thyroid cancer, accompanied with a high ratio of epigenetic adjustment, which occurs more than genetic mutations. In this study, we aimed to evaluate the synergistic anticancer effect (in vitro and in vivo) of the new combination of N-hydroxy-7-(2-naphthylthio) heptanomide (HNHA) and sorafenib with radiation therapy in pre-clinical models of ATC. The ATC cell lines, YUMC-A1 and YUMC-A2, were isolated from the current patients who were treated with HNHA and sorafenib, either as monotherapy or combination therapy. Synergistic anticancer effect of the combination therapy on the intracellular signaling pathways and cell cycle was assessed via flow cytometry and immunoblot analysis. To examine tumor shrinkage activity in vivo, an ATC cell line-derived mouse xenograft model was used. Results showed that the combination therapy of HNHA and sorafenib with radiation promoted tumor suppression via caspase cleavage and cell cycle arrest in patient-derived ATC. In addition, the combination therapy of HNHA and sorafenib with radiation was more effective against ATC than therapy with HNHA or sorafenib with radiation. Thus, the combination of HNHA and sorafenib with radiation may be used as a novel curative approach for the treatment of ATC.

Patient-Derived, Drug-Resistant Colon Cancer Cells Evade Chemotherapeutic Drug Effects via the Induction of Epithelial-Mesenchymal Transition-Mediated Angiogenesis.

Cancer cells can exhibit resistance to different anticancer drugs by acquiring enhanced anti-apoptotic potential, improved DNA injury resistance, diminished enzymatic inactivation, and enhanced permeability, allowing for cell survival. However, the genetic mechanisms for these effects are unknown. Therefore, in this study, we obtained drug-sensitive HT-29 cells (commercially) and drug-resistant cancer cells (derived from biochemically and histologically confirmed colon cancer patients) and performed microarray analysis to identify genetic differences. Cellular proliferation and other properties were determined after treatment with oxaliplatin, lenvatinib, or their combination. In vivo, tumor volume and other properties were examined using a mouse xenograft model. The oxaliplatin and lenvatinib cotreatment group showed more significant cell cycle arrest than the control group and groups treated with either agent alone. Oxaliplatin and lenvatinib cotreatment induced the most significant tumor shrinkage in the xenograft model. Drug-resistant and metastatic colon cancer cells evaded the anticancer drug effects via angiogenesis. These findings present a breakthrough strategy for treating drug-resistant cancer.

Impact of Age-Related Genetic Differences on the Therapeutic Outcome of Papillary Thyroid Cancer.

The incidence of papillary thyroid carcinoma (PTC) has been increasing worldwide. PTC is the most common type of differentiated thyroid cancer and usually shows good prognosis. However, some PTC is driven to advanced stage by epithelial-mesenchymal transition (EMT)-mediated drug resistance, which is particularly noticeable in pediatric patients. There are limited options for systemic treatment, necessitating development of new clinical approaches. Here, we aimed to clarify genetic differences due to age of patients with PTC, and thereby aid in developing novel therapeutics. Patients with biochemically and histologically confirmed PTC were included in this study. PTC cells were acquired from young and older patients showing drug resistance, and were compared via microarray analysis. Cellular proliferation and other properties were determined after treatments with lenvatinib and sorafenib. In vivo, tumor volume and other properties were examined using a mouse xenograft model. Lenvatinib-treated group showed obvious suppression of markers of anti-apoptosis, EMT, and the FGFR signaling pathway, compared with control and Sorafenib-treated group. In the xenograft models, lenvatinib treatment induced significant tumor shrinkage and blocked the proto-oncogene Bcl-2 (B cell lymphoma/leukemia gene-2) and FGFR signaling pathway, along with reduced levels of EMT markers, compared with control and Sorafenib-treated group. Our findings clarify the age-dependent characteristics of pediatric PTC, giving insights into the relationship between young age and poor prognosis. Furthermore, it provides a basis for developing novel therapeutics tailored to the age at diagnosis.

VEGF-C induced by TGF- ß1 signaling in gastric cancer enhances tumor-induced lymphangiogenesis.

BACKGROUND: The role of TGF-ß1 in lymph node metastasis and lymphangiogenesis, one of the most important steps of gastric cancer dissemination, is largely unknown. The goal of this study was to investigate the role of TGF-ß1 signaling and its molecular mechanisms involved in lymphangiogenesis of gastric cancer. METHODS: Two gastric cell line models, MKN45 and KATOIII, were selected for this study. The protein expression of TGF-ß1 pathway molecules and VEGF-C were examined with western blot, or ELISA according to TGF-ß1 treatment. To explore whether Smad3 binds to the specific DNA sequences in the VEGFC promoter, we performed an electrophoretic mobility shift assay. Lymphatic tube forming assay and gastric cancer xenograft mouse models were also used to elucidate the effect of TGF-ß1 on lymphangiogenesis. RESULTS: TGF-ß1 induced the activation of Smad2/3 and Smad pathway-modulated VEGF-C expression in gastric cancer cell line models. Phosphorylated and activated Smad3 in the nucleus bound to the promoter of VEGFC in KATO III cells. Of note, in MKN45 cells, the Smad-independent AKT pathway was also activated in response to TGF-ß1 and induced VEGF-C expression. Inhibition of TGF-ß1 signaling down-regulated the expression of VEGF-C. We also confirmed, through tube forming assay and tumor xenograft mouse model, that TGF-ß1 increased lymphatic formation, while TGF-ß1 inhibition blocked lymphangiogenesis. CONCLUSION: Smad-dependent and -independent TGF-ß1 pathways induce VEGF-C, which make lymphangiogenesis around tumor. These findings suggest that TGF-ß might be a potential therapeutic target for preventing gastric cancer progression and dissemination.

Synergistic Activity of Paclitaxel, Sorafenib, and Radiation Therapy in advanced Renal Cell Carcinoma and Breast Cancer.

Advanced cancer has been shown to be associated with a higher percentage of epigenetic changes than with genetic mutations. Preclinical models have shown that the combination of paclitaxel, sorafenib, and radiation therapy (RT) plays a crucial role in renal cell carcinoma (RCC) and breast cancer. This study aimed to investigate the involvement of mitochondrial cytochrome c-dependent apoptosis in the mechanism of action of a combination of paclitaxel, sorafenib, and RT in RCC and breast cancer. RCC and breast cancer cell lines were exposed to paclitaxel and sorafenib alone or combined in the presence of radiation, and cell viability was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. The synergistic anticancer effects of the combination therapy on cell cycle and intracellular signaling pathways were estimated using flow cytometry and immunoblot analysis. RCC and breast cancer cell line xenograft models were used to examine the antitumor activity in vivo. Our results suggest that paclitaxel, sorafenib, and RT synergistically decreased the viability of RCC and breast cancer cells and significantly induced their apoptosis, as shown by caspase-3 cleavage. Paclitaxel, sorafenib, and radiation cotreatment reduced antiapoptotic factor levels in these cells and, thereby, significantly reduced the tumor volume of RCC and breast cancer cell xenografts. The current study suggests that paclitaxel, sorafenib, and radiation cotreatment was more effective than cotreatment with paclitaxel or sorafenib and radiation. These findings may offer a new therapeutic approach to RCC and breast cancer.

SoLAT (Sorafenib Lenvatinib alternating treatment): a new treatment protocol with alternating Sorafenib and Lenvatinib for refractory thyroid Cancer.

BACKGROUND: In the last decade, several tyrosine kinase inhibitors (TKIs), which disrupt pathways involved in the proliferation and tumorigenesis of thyroid cancer, have been extensively studied. Two different TKIs, lenvatinib and sorafenib, were recently approved by both the US FDA and European Medicine Agency. Until date, the duration of the TKI response is not sufficient and resistance eventually occurs. The goal of this study was to investigate a new treatment protocol, SoLAT, using sorafenib and lenvatinib alternatively on refractory thyroid cancer. METHODS: Patient-derived aggressive papillary thyroid cancer (PTC) cell lines from patients with biochemical and histologically proven aggressive RAI-refractory papillary thyroid cancer were exposed to sorafenib and lenvatinib alternatively. Human thyroid cancer cell xenografts were obtained by injecting patient-derived aggressive PTC cell lines into the flank of female BALB/c nude mice. Tumor-bearing mice were treated with sorafenib and lenvatinib alternatively. Cell viability assay, immunofluorescence analysis, confocal imaging, immunoblot analysis, flow cytometry analysis of cell cycle and a tube formation assay were performed. RESULTS: SoLAT was more effective for advanced PTC cell lines than individual treatment. Immunoblot analysis showed that SoLAT markedly increased levels of cell cycle inhibitors (p53 and p21), and pro-apoptotic factors (Apaf-1 and cleaved caspase 3) and decreased levels of positive cell cycle regulators (cyclin D1, CDK4, CDK6) and anti-apoptotic factors (p-NFκB, Bcl-2). Increased sub-G0/G1 population was observed in the SoLAT group, leading to apoptosis, cell cycle arrest, and strong inhibition of advanced PTC cell viability. SoLAT reduced the level of EMT markers such as vimentin, E-cadherin, Snail and Zeb1 by FGFR inhibition. In the xenograft model, individual treatment with sorafenib or lenvatinib did not markedly suppress patient-derived aggressive PTC cell xenograft tumors, whereas SoLAT significantly suppressed the proliferation of these tumors. CONCLUSIONS: SoLAT was more effective than individual treatment with sorafenib or lenvatinib in inhibiting PTC progression by inducing cell cycle arrest. Studies using both in vitro cell culture and an in vivo xenograft model provided evidence of tumor shrinkage with SoLAT. We suggest that these effects may be due to reduced EMT-mediated drug resistance in the aggressive PTC model.

Clinical and genomic landscape of gastric cancer with a mesenchymal phenotype.

Gastric cancer is a heterogeneous cancer, making treatment responses difficult to predict. Here we show that we identify two distinct molecular subtypes, mesenchymal phenotype (MP) and epithelial phenotype (EP), by analyzing genomic and proteomic data. Molecularly, MP subtype tumors show high genomic integrity characterized by low mutation rates and microsatellite stability, whereas EP subtype tumors show low genomic integrity. Clinically, the MP subtype is associated with markedly poor survival and resistance to standard chemotherapy, whereas the EP subtype is associated with better survival rates and sensitivity to chemotherapy. Integrative analysis shows that signaling pathways driving epithelial-to-mesenchymal transition and insulin-like growth factor 1 (IGF1)/IGF1 receptor (IGF1R) pathway are highly activated in MP subtype tumors. Importantly, MP subtype cancer cells are more sensitive to inhibition of IGF1/IGF1R pathway than EP subtype. Detailed characterization of these two subtypes could identify novel therapeutic targets and useful biomarkers for prognosis and therapy response.

Protective effects of guggulsterone against colitis are associated with the suppression of TREM-1 and modulation of macrophages.

Triggering receptor expressed on myeloid cells 1 (TREM-1)-expressing intestinal macrophages are significantly increased in the colons of patients with inflammatory bowel disease (IBD). We focused here on the effects of guggulsterone on macrophage modulation in colitis as a potential therapeutic molecule in human IBD and explore the underlying mechanisms. Gene expression in macrophages was examined and wound-healing assay using HT-29 cells was performed. Colitis in wild-type and IL-10-, Toll-like receptor 4 (TLR4)-, and myeloid differentiation primary response 88 (MyD88)-deficient mice was induced via the administration of 2,4,6-trinitrobenzene sulfonic acid (TNBS) into the colon. In both in vitro and in vivo experiments, guggulsterone suppressed intestinal inflammation amplified by TREM-1 stimulation, in which the suppression of NF-κB, activating protein-1, and proteasome pathways was involved. In the TNBS-induced colitis model, guggulsterone reduced disease activity index scores and TREM-1 expression, stimulated IL-10 production, and improved survival in wild-type mice. These effects were not observed in IL-10-, TLR4-, and MyD88-deficient mice. Guggulsterone also suppressed M1 polarization, yet induced the M2 phenotype in macrophages from IBD patients as well as from mice. These findings indicate that guggulsterone blocks the hyperactivation of macrophages via TREM-1 suppression and induces M2 polarization via IL-10 mediated by the TLR4 signaling pathway. Furthermore, this study provides a new rationale for the therapeutic potential of guggulsterone in the treatment of IBD. NEW & NOTEWORTHY We found that guggulsterone attenuates triggering receptor expressed on myeloid cells 1 (TREM-1)-mediated hyperactivation of macrophages and polarizes macrophages toward the M2 phenotype. This was mediated by IL-10 and partly Toll-like receptor 4 signaling pathways. Overall, these data support that guggulsterone as a natural plant sterol modulates macrophage phenotypes in colitis, which may be of novel therapeutic importance in inflammatory bowel disease treatment.

Anti-cancer Effects of HNHA and Lenvatinib by the Suppression of EMT-Mediated Drug Resistance in Cancer Stem Cells.

Anaplastic thyroid cancer (ATC) constitutes less than 2% of total thyroid cancers but accounts for 20-40% of thyroid cancer-related deaths. Cancer stem cell drug resistance represents a primary factor hindering treatment. This study aimed to develop targeted agents against thyroid malignancy, focusing on individual and synergistic effects of HNHA (histone deacetylase), lenvatinib (FGFR), and sorafenib (tyrosine kinase) inhibitors. Patients with biochemically and histologically proven papillary thyroid cancer (PTC) and ATC were included. Cell samples were obtained from patients at the Thyroid Cancer Center, Gangnam Severance Hospital, Yonsei University College of Medicine, Seoul, Korea. PTC and ATC cells were treated with lenvatinib or sorafenib, alone or in combination with HNHA. Tumor-bearing mice (10/group) were administered 10 mg/kg lenvatinib (p.o.) or 40 mg/kg sorafenib (p.o.), alone or in combination with 25 mg/kg HNHA (i.p.) once every three days. Gene expression in patient-derived PTC and ATC cells was compared using a microarray approach. Cellular apoptosis and proliferation were examined by immunohistochemistry and MTT assays. Tumor volume and cell properties were examined in the mouse xenograft model. HNHA-lenvatinib combined treatment induced markers of cell cycle arrest and apoptosis and suppressed anti-apoptosis markers, epithelial-mesenchymal transition (EMT), and the FGFR signaling pathway. Combined treatment induced significant tumor shrinkage in the xenograft model. HNHA-lenvatinib combination treatment thus blocked the FGFR signaling pathway, which is important for EMT. Treatment with HNHA-lenvatinib combination was more effective than either agent alone or sorafenib-HNHA combination. These findings have implications for ATC treatment by preventing drug resistance in cancer stem cells.

Survival of Cancer Stem-Like Cells Under Metabolic Stress via CaMK2α-mediated Upregulation of Sarco/Endoplasmic Reticulum Calcium ATPase Expression.

Purpose: Cancer cells grow in an unfavorable metabolic milieu in the tumor microenvironment and are constantly exposed to metabolic stress such as chronic nutrient depletion. Cancer stem-like cells (CSC) are intrinsically resistant to metabolic stress, thereby surviving nutrient insufficiency and driving more malignant tumor progression. In this study, we aimed to demonstrate the potential mechanisms by which CSCs avoid Ca2+-dependent apoptosis during glucose deprivation.Experimental Design: We investigated cell viability and apoptosis under glucose deprivation, performed genome-wide transcriptional profiling of paired CSCs and parental cells, studied the effect of calcium/calmodulin-dependent protein kinase 2 alpha (CaMK2α) gene knockdown, and investigated the role of nuclear factor kappa B (NFκB) in CSCs during time-dependent Ca2+-mediated and glucose deprivation-induced apoptosis. We also observed the effect of combined treatment with 2-deoxy-d-glucose, a metabolic inhibitor that mimics glucose deprivation conditions in mouse xenograft models, and thapsigargin, a specific inhibitor of sarco/endoplasmic reticulum Ca2+-ATPase (SERCA).Results: We demonstrated the coordinated upregulation of SERCA in CSCs. SERCA, in turn, is transcriptionally regulated by CaMK2α via NFκB activation. Combined treatment with 2-deoxy-d-glucose and thapsigargin, a specific inhibitor of SERCA, significantly reduced tumor growth compared with that in untreated control animals or those treated with the metabolic inhibitor alone.Conclusions: The current study provides compelling evidence that CaMK2α acts as a key antiapoptosis regulator in metabolic stress-resistant CSCs by activating NFκB. The latter induces expression of SERCA, allowing survival in glucose-deprived conditions. Importantly, our combination therapeutic strategy provides a novel approach for the clinical application of CSC treatment. Clin Cancer Res; 24(7); 1677-90. ©2017 AACR.

Synergistic Activity of N-hydroxy-7-(2-naphthylthio) Heptanomide and Sorafenib Against Cancer Stem Cells, Anaplastic Thyroid Cancer.

Anaplastic thyroid carcinoma (ATC) although rare is the most deadly form of thyroid cancer. The fatality rate for ATC is high-pitched, the survival rate at 1 year after diagnosis is <20%. Control of ATC is severely hard and widespread with unpredictability. We Previous proved that histone gene reviser and epigenetic changes role significant parts in papillary and anaplastic thyroid cancer tumorigenesis. Herein, the goal of this study was to investigate the anti-tumor activities of a HDAC inhibitor, HNHA alone and in combination with sorafenib in ATC cells in vitro and in vivo and to explore its effects on apoptotic cell death pathways. Three ATC cell lines were exposed to sorafenib in the presence or absence of HNHA, and cell viability was determined by MTT assay. Effects of combined treatment on cell cycle and intracellular signaling pathways were assessed by flow cytometry and western blot analysis. The ATC cell lines xenograft model was used to examine the anti-tumor activity in vivo. Our data showed that HNHA and sorafenib synergistically decreased cell viability in ATC cells, and also significantly increased apoptotic cell death in these cells, as proved by the cleavage of caspase-3 and DNA fragmentation. HNHA and sorafenib combination was reduced anti-apoptotic factor in ATC. Thus, combination therapy with HNHA and sorafenib significantly decreased vessel density, and most significantly reduced tumor volume and increased survival in ATC xenografts. These results propose that HNHA in combination with sorafenib has significant anti-cancer activity in preclinical models, potentially suggesting a new clinical approach for patients of advanced thyroid cancer type.