Sorafenib inhibits intracellular signaling pathways and induces cell cycle arrest and cell death in thyroid carcinoma cells irrespective of histological origin or BRAF mutational status

Combination therapy of tyrosine kinase inhibitor sorafenib with the HSP90 inhibitor onalespib as a novel treatment regimen for thyroid cancer

Thyroid cancer is the most common endocrine malignancy, affecting nearly 600,000 new patients worldwide. Treatment with the BRAF inhibitor sorafenib partially prolongs progression-free survival in thyroid cancer patients, but fails to improve overall survival. This study examines enhancing sorafenib efficacy by combination therapy with the novel HSP90 inhibitor onalespib. In vitro efficacy of sorafenib and onalespib monotherapy as well as in combination was assessed in papillary (PTC) and anaplastic (ATC) thyroid cancer cells using cell viability and colony formation assays. Migration potential was studied in wound healing assays. The in vivo efficacy of sorafenib and onalespib therapy was evaluated in mice bearing BHT-101 xenografts. Sorafenib in combination with onalespib significantly inhibited PTC and ATC cell proliferation, decreased metabolic activity and cancer cell migration. In addition, the drug combination approach significantly inhibited tumor growth in the xenograft model and prolonged the median survival. Our results suggest that combination therapy with sorafenib and onalespib could be used as a new therapeutic approach in the treatment of thyroid cancer, significantly improving the results obtained with sorafenib as monotherapy. This approach has the potential to reduce treatment adaptation while at the same time providing therapeutic anti-cancer benefits such as reducing tumor growth and metastatic potential.

Synergic Induction of Autophagic Cell Death in Anaplastic Thyroid Carcinoma

Anaplastic thyroid carcinoma (ATC) has poor prognosis, high mortality rate and lack of effective therapy. A synergic combination of PD-L1 antibody together with cell death promoting substances like deacetylase inhibitors (DACi) and multi-kinase inhibitors (MKI) could sensitize ATC cells and promote decay by autophagic cell death. The PD-L1-inhibitor atezolizumab synergized with panobinostat (DACi) and sorafenib (MKI) leading to significant reduction of the viability, measured by real time luminescence, of three different patient-derived primary ATC cells, of C643 cells and follicular epithelial thyroid cells too. Solo administration of these compounds caused a significant over-expression of autophagy transcripts; meanwhile autophagy proteins were almost not detectable after the single administration of panobinostat, thus supporting a massive autophagy degradation process. Instead, the administration of atezolizumab caused an accumulation of autophagy proteins and the cleavage of the active caspases 8 and 3. Interestingly, only panobinostat and atezolizumab were able to exacerbate the autophagy process by increasing the synthesis, the maturation and final fusion with the lysosomes of the autophagosome vesicles. Despite ATC cells could be sensitized by atezolizumab via the cleavage of the caspases, no reduction of cell proliferation or promotion of cell death was observed. The apoptosis assay evidenced the ability of panobinostat alone and in combination with atezolizumab to induce the phosphatidil serine exposure (early apoptosis) and further the secondary necrosis. Instead, sorafenib was only able to cause necrosis. The increase of caspases activity induced by atezolizumab, the apoptosis and autophagy processes promoted by panobinostat synergize thus promoting cell death in well-established and primary anaplastic thyroid cancer cells. The combined therapy could represent a future clinical application for the treatment of such lethal and untreatable solid cancer.

Therapeutic Effects of Crocin Alone or in Combination with Sorafenib against Hepatocellular Carcinoma: In Vivo & In Vitro Insights

This study investigated the therapeutic effects of the phytochemical crocin alone or in combination with sorafenib both in rats chemically induced with hepatocellular carcinoma (HCC) and in human liver cancer cell line (HepG2). Male rats were randomly divided into five groups, namely, control group, HCC induced group, and groups treated with sorafenib, crocin or both crocin and sorafenib. HCC was induced in rats with a single intraperitoneal injection of diethylnitrosamine (DEN), then 2-acetylaminofluorene (2-AAF). The HCC-induced rats showed a significant decrease in body weight compared to animals treated with either or both examined drugs. Serum inflammatory markers (C-reactive protein (CRP); interleukin-6 (IL-6); lactate dehydrogenase (LDH), and oxidative stress markers were significantly increased in the HCC group and were restored upon treatment with either or both of therapeutic molecules. Morphologically, the HCC-induced rats manifested most histopathological features of liver cancer. Treatment with either or both of crocin and sorafenib successfully restored normal liver architecture. The expression of key genes involved in carcinogenesis (TNFα, p53, VEGF and NF-κB) was highly augmented upon HCC induction and was attenuated post-treatment with either or both examined drugs. Treatment with both crocin and sorafenib improved the histopathological and inflammation parameters as compared to single treatments. The in vivo anti-cancer effects of crocin and/or sorafenib were supported by their respective cytotoxicity on HepG2 cells. Crocin and sorafenib displayed an anti-tumor synergetic effect on HepG2 cells. The present findings demonstrated that a treatment regimen with crocin and sorafenib reduced liver toxicity, impeded HCC development, and improved the liver functions.

The Role of Caspase Family in Acute Brain Injury: The Potential Therapeutic Targets in the Future

The caspase family is commonly involved in the pathophysiology of acute brain injury (ABI) through complex apoptotic, pyroptotic, and inflammatory pathways. Current translational strategies for caspase modulation in ABI primarily focus on caspase inhibitors. Because there are no caspase-inhibiting drugs approved for clinical use on the market, the development of caspase inhibitors remains an attractive challenge for researchers and clinicians. Therefore, we conducted the present review with the aim of providing a comprehensive introduction of caspases in ABI. In this review, we summarized the available evidence and potential mechanisms regarding the biological function of caspases. We also reviewed the therapeutic effects of caspase inhibitors on ABI and its subsequent complications. However, various important issues remain unclear, prompting further verification of the efficacy and safety regarding clinical application of caspase inhibitors. We believe that our work will be helpful to further understand the critical role of the caspase family and will provide novel therapeutic potential for ABI treatment.

Effect of Kinase Inhibitors on the Technetium-99m Uptake into Thyroid Carcinoma Cells In Vitro

BACKGROUND/AIM

We evaluated the potential of the kinase inhibitors sorafenib, lenvatinib and selumetinib on increasing the uptake of technetium-99m into thyroid cancer cells.

MATERIALS AND METHODS

Four established cell lines and three patient's cell cultures were treated with 0.1, 1 and 5 μM of sorafenib, lenvatinib and selumetinib for 72 hours. After incubation with 1 MBq of technetium-99m, the radioactivity uptake was measured.

RESULTS

The experiments showed heterogeneous results. Maximum technetium-99m uptake increases of 312% (sorafenib), 326% (lenvatinib) and 759% (selumetinib) were obtained using the highest applied concentrations. In some tests, an uptake reduction or no effect was observed.

CONCLUSION

Kinase inhibitors have a positive effect on technetium-99m uptake. Due to study limitations, a redifferentiating effect of the drugs could not be definitely proven. Unspecific cytotoxicity might have a confounding effect.

Sorafenib Modulates the LPS- and Aβ-Induced Neuroinflammatory Response in Cells, Wild-Type Mice, and 5xFAD Mice

Sorafenib is FDA-approved for the treatment of primary kidney or liver cancer, but its ability to inhibit many types of kinases suggests it may have potential for treating other diseases. Here, the effects of sorafenib on neuroinflammatory responses in vitro and in vivo and the underlying mechanisms were assessed. Sorafenib reduced the induction of mRNA levels of the proinflammatory cytokines COX-2 and IL-1β by LPS in BV2 microglial cells, but in primary astrocytes, only COX-2 mRNA levels were altered by sorafenib. Interestingly, sorafenib altered the LPS-mediated neuroinflammatory response in BV2 microglial cells by modulating AKT/P38-linked STAT3/NF-kB signaling pathways. In LPS-stimulated wild-type mice, sorafenib administration suppressed microglial/astroglial kinetics and morphological changes and COX-2 mRNA levels by decreasing AKT phosphorylation in the brain. In 5xFAD mice (an Alzheimer’s disease model), sorafenib treatment daily for 3 days significantly reduced astrogliosis but not microgliosis. Thus, sorafenib may have therapeutic potential for suppressing neuroinflammatory responses in the brain.

Serum CYFRA 21.1 Level Predicts Disease Course in Thyroid Cancer with Distant Metastasis

Simple Summary

The role of serum Cyfra 21.1 as a biomarker in thyroid cancer has yet to be validated. This study investigated the diagnostic or prognostic role of serum Cyfra 21.1 in thyroid cancer. In the present analysis, we found that serum Cyfra 21.1 was increased in thyroid cancer with distant metastasis compared with thyroid cancer without metastasis. Furthermore, in progressive disease when thyroglobulin was undetectable or thyroglobulin monitoring was useless because of thyroglobulin antibody, serial follow-up based on serum Cyfra 21.1 levels might be used as an alternative biomarker for disease monitoring.

Abstract

Background: Serum Cyfra 21.1, the soluble fragment of CK19, has been used as a prognostic tumor marker in various cancers, indicating poor tumor differentiation and increased metastasis. Methods: We analyzed the serum Cyfra 21.1 level in 51 consecutive patients with thyroid cancer manifesting distant metastasis treated with prior total thyroidectomy. Serum Cyfra 21.1 levels of 26 thyroid cancer patients without metastasis and 50 healthy individuals were used for comparison. Results: Higher serum Cyfra 21.1 levels were detected in thyroid cancer patients with distant metastasis compared with healthy subjects and thyroid cancer patients without metastasis (p = 0.012). Serum Cyfra 21.1 levels were significantly increased in patients with positive BRAF V600E mutation (p = 0.019), undergoing Tyrosine Kinase Inhibitor (TKI) therapy (p = 0.008), with radioiodine-refractory status (p = 0.047), and in disease progression compared with those manifesting stable disease (p = 0.007). In progressive disease with undetectable or unmonitored thyroglobulin because of thyroglobulin antibody, serum Cyfra 21.1 was useful as a biomarker for follow-up of disease course. Conclusion: Serum Cyfra 21.1 in thyroid cancer patients might represent an alternative biomarker predicting tumor progression, especially in cases not associated with serum Tg levels.

Synergistic anticancer activity of sorafenib, paclitaxel, and radiation therapy on anaplastic thyroid cancer in vitro and in vivo

BACKGROUND

This study aimed to investigate the antitumor activity of paclitaxel with radiation and sorafenib in anaplastic thyroid cancer (ATC) cells in vitro and in vivo.

METHODS

The 8505C ATC cell line was exposed to radiation, sorafenib, and paclitaxel each or in combination. The effects of combined treatment on the cell cycle and intracellular signaling pathways were assessed using flow cytometry and western blot analysis. An ATC cell line xenograft model was used to examine antitumor activity in vivo.

RESULTS

Radiation, paclitaxel plus sorafenib synergistically decreased cell viability in ATC cells and significantly increased apoptotic cell death. The combination of paclitaxel, sorafenib with radiation reduced the antiapoptotic factor in ATC. This combination therapy significantly reduced the tumor volume and increased survival in the ATC xenograft model.

CONCLUSIONS

These results suggest that the combination of radiation and paclitaxel plus sorafenib has significant anticancer activity in preclinical models.

Carnosic acid increases sorafenib-induced inhibition of ERK1/2 and STAT3 signaling which contributes to reduced cell proliferation and survival of hepatocellular carcinoma cells

Hepatocellular carcinoma (HCC) has increasing worldwide incidence but when unresectable lacks curative options. Treatment with a kinase inhibitor Sorafenib (Sf), while initially effective, results in only short increases in patient survival, thus there is a need for improved treatment regimens. Numerous treatment regimens have been explored wherein Sf is combined with other agents, such as non-toxic botanicals like Curcumin or Silibinin. Recently, we have shown that carnosic acid (CA), a component of the food preservative Rosemary Extract, can markedly enhance the cytotoxic actions of Sf in several cell lines derived from HCC, but not in the cell line Hu1545 derived from normal hepatocytes. CA has been shown to enhance Sf-induced cell death in the neoplastic cell lines, principally due to the composite of increased apoptosis and cytotoxic autophagy. In the present study we focused on the mechanisms that underlie the reduced proliferation and survival of HCC cells when CA is added to Sf and how this relates to the increase in Sf-induced DNA damage as well as to the elevation of cytoplasmic levels of reactive oxygen species (ROS). Importantly, the elevation of ROS levels induced by Sf was increased by adding CA. We found that CA enhanced Sf-induced prolongation of cell cycle, and the overall decrease in cell growth was associated with reduced activation of both STAT3 transcription factor (TF) and extracellular signal-regulated protein kinase (Erk)1/2. Our data suggest that a regimen incorporating CA, an inexpensive and non-toxic food additive, in the treatment of advanced HCC merits clinical evaluation.

Sorafenib Inhibits Proliferation, Migration and Invasion of Breast Cancer Cells

INTRODUCTION

Metastatic breast cancer has poor prognosis due to limited therapeutic options. Protein kinase dysregulations have a major role in breast cancer progression and metastasis. In this study, we investigated the anti-cancer activity of sorafenib, a multikinase inhibitor, which targets receptor tyrosine kinases in breast cancer. Although treatment with sorafenib has increased the patient survival and inhibited metastatic migration in hepatocellular carcinoma, its role in breast cancer migration, metastasis, and intracellular signaling modulation is unknown.

METHODS

Breast cancer cell lines MCF7 and MDA-MB-231 were treated with sorafenib and its effect on proliferation, migration, invasion and gene expression was analyzed.

RESULTS

We found that sorafenib has an anti-proliferative and cytotoxic effect on breast cancer cells. Importantly, sorafenib inhibited the migration and invasion of breast cancer cells in vitro. Mechanistically, sorafenib increased mitochondrial superoxide production, suppressed breast cancer stem cell self-renewal, inhibited epithelial mesenchymal transition and ERK signaling.

CONCLUSION

Thus, sorafenib has anti-cancer activity against breast cancer cells and could improve the survival of breast cancer patients by inhibiting their invasive and metastatic properties.

KinomeRun: An interactive utility for kinome target screening and interaction fingerprint analysis towards holistic visualization on kinome tree

Kinases are key targets for many of the pathological conditions. Inverse screening of ligands serves as an essential mode to identify potential kinase targets in modern drug discovery research. Hence, we intend to develop KinomeRun, a robust pipeline for inverse screening and kinome tree visualization through the seamless integration of kinome structures, docking and kinome-drug interaction fingerprint analysis. In this pipeline, the hurdle of residue numbering in kinome is also resolved by creating a common index file with the conserved kinase pocket residues for comparative interaction analysis. KinomeRun can be used to screen the ligands of interest docked against multiple kinase structures in parallel around the kinase binding site and also to filter out the targets with unique interaction patterns. This automation is essential for prioritization of kinase targets that show specificity for a given drug and will also serve as a crucial tool kit for holistic approaches in kinase drug discovery. KinomeRun is developed using python and bash programming language and is distributed freely under the GNU GPL licence-3.0 and can be downloaded at https://github.com/inpacdb/KinomeRun. The tutorial videos for installation, target screening and customized filtration are available at https://www.youtube.com/playlist?list=PLuIaEFtMVgQ7v__WigQH9ilGVxrfI1LKs and also be downloaded for offline viewing from the github link.

Polymer Nanoformulation of Sorafenib and All-Trans Retinoic Acid for Synergistic Inhibition of Thyroid Cancer

Part of differentiated thyroid cancer will relapse or develop into dedifferentiated thyroid cancer after standard therapy, such as surgery or radionuclide therapy. Sorafenib (SOR) is recommended for the treatment of advanced or radioiodine-refractory thyroid cancer. The monotherapy using SOR is often hampered by its modest efficacy, serve systemic toxicity, and high occurrence of drug resistance. In order to enhance the antitumor effect of SOR and reduce its side effects, SOR and all-trans retinoic acid (ATRA), a differentiation-promoting drug, were loaded into poly(ethylene glycol)–poly(lactide-co-glycolide) (PEG–PLGA) polymer micelles in this study. The drug-loaded micelles, PM/(SOR+ATRA), exhibited relatively slow drug release and effective cell uptake. Compared with other treatment groups, the PM/(SOR+ATRA) treatment group showed the most significant antitumor effect and minimal systemic toxicity toward the FTC-133 thyroid cancer-bearing BALB/c nude mouse model. Immunofluorescence analysis confirmed that PM/(SOR+ATRA) could significantly promote apoptosis and re-differentiation of tumor cells. All the results demonstrated that polymer micelles loaded with SOR and ATRA could treat thyroid cancer more effectively and safely.

Targeted ErbB3 cancer therapy: A synergistic approach to effectively combat cancer

Surface modification of nanoparticles with aptamer is gaining popularity lately due to its selective targeting and low immunogenicity. In this study, sorafenib tosylate (SFB) was loaded in biodegradable PLGA nanoparticles prepared by solvent evaporation method. The surfaces of drug deprived and drug-loaded particles (PN and PNS, respectively) were coupled with aptamer to target ErbB3 using EDC/NHS chemical modification. Nanoparticles were characterized with regard to their size, shape and chemical composition by dynamic light scattering, atomic force microscopy, FTIR and elemental analysis respectively. To evaluate the particles in vitro cell culture studies were performed. Cell viability assay, pathway analysis and apoptosis assay showed cellular toxicity in the presence of aptamer in PNS-Apt (p < 0.001). Metastatic progression assay showed decreased cell migration in the presence of aptamer and SFB. Confocal laser scanning microscopy was used to visualize the receptor-mediated time-dependent intracellular uptake and distribution of the nanoparticles throughout the cytoplasm. The findings of the current study demonstrated the potential efficacy of the surface modified SFB-loaded particles against ErbB3.

Peptide P11 suppresses the growth of human thyroid carcinoma by inhibiting the PI3K/AKT/mTOR signaling pathway

Thyroid carcinoma is the most common endocrine malignancy, and the incidence of thyroid carcinoma is increasing in recent decades. CYYGQSKYC (P6), a nonapeptide with anti-lymphangiogenic effect by its binding to VEGFR-3 and selectively inhibiting VEGF-C binding to VEGFR-3, could suppress the migration and invasion of cancer cells. LSPPRYP (P9) acts as an effective bFGF/FGFR antagonist and inhibits the growth of the murine melanoma B16-F10 cells. In order to increase the anti-tumor effects of P6 and P9, we connected P6 with P9 via a flexible linker Gly-Gly-Gly (GGG) to reconstruct a novel peptide P11, CYYGQSKYCGGGLSPPRYP. In the present study, the mechanism of action of peptide P11 on the growth of human thyroid carcinoma cells both in vitro and in vivo was determined. Our results showed that peptide P11 inhibited the proliferation, viability, migration, and invasion of human thyroid carcinoma cells. Peptide P11 increased the apoptosis and decreased the protein levels of p-PI3K, p-AKT, and p-mTOR in human thyroid carcinoma cells. In addition, P11 could effectively inhibit the growth of human thyroid carcinoma xenograft tumors in nude mice. In conclusion, peptide P11 could inhibit the growth of human thyroid carcinoma by inhibiting the PI3K/Akt/mTOR signaling pathway. Novel peptides can be designed and applied for the treatment of various types of cancer.

Epigallocatechin-3-gallate inhibits the growth and increases the apoptosis of human thyroid carcinoma cells through suppression of EGFR/RAS/RAF/MEK/ERK signaling pathway

Background

Thyroid cancer is the most common type of endocrine malignancy and the incidence rate is rapidly increasing worldwide. Epigallocatechin-3-gallate (EGCG) could suppress cancer growth and induce apoptosis in many types of cancer cells. However, the mechanism of action of EGCG on the growth of human thyroid carcinoma cells has not been fully illuminated.

Methods

Cell proliferation and viability were detected by EdU and MTS assays. Cell cycle distribution was measured by flow cytometry. Migration and invasion were evaluated by scratch and transwell assays. Apoptotic levels were detected by TUNEL staining and western blotting. The protein levels of EGFR/RAS/RAF/MEK/ERK signaling pathway were detected by western blotting. The in vivo results were determined by tumor xenografts in nude mice. The in vivo proliferation, tumor microvessel density, and apoptosis were detected by immunohistochemistry.

Results

EGCG inhibited the proliferation, viability, and cell cycle progression in human thyroid carcinoma cells. EGCG decreased the migration and invasion, but increased the apoptosis of human thyroid carcinoma cells. EGCG reduced the protein levels of phospho (p)-epidermal growth factor receptor (EGFR), H-RAS, p-RAF, p-MEK1/2, and p-extracellular signal-regulated protein kinase 1/2 (ERK1/2) in human thyroid carcinoma cells. EGCG inhibited the growth of human thyroid carcinoma xenografts by inducing apoptosis and down-regulating angiogenesis.

Conclusions

EGCG could reduce the growth and increase the apoptosis of human thyroid carcinoma cells through suppressing the EGFR/RAS/RAF/MEK/ERK signaling pathway. EGCG can be developed as an effective therapeutic agent for the treatment of thyroid cancer.

Transferrin receptor-targeted HMSN for sorafenib delivery in refractory differentiated thyroid cancer therapy

Background

Thyroid cancer becomes the most common endocrine cancer with the greatest growing incidence in this decade. Sorafenib is a multikinase inhibitor for the treatment of progressive radioactive iodine-refractory differentiated thyroid cancer (DTC), while the off-target toxicity effect is usually inconvenient for patients taking.

Methods

In this study, hollow mesoporous silica nanoparticles (HMSNs) with transferrin modification (Tf-HMSNs) were loaded with sorafenib (sora@Tf-HMSNs) to help targeted delivery of sorafenib. Due to the biocompatible Tf shell, Tf-HMSNs exhibited excellent bio-compatibility and increased intracellular accumulation, which improved the targeting capability to cancer cells in vitro and in vivo.

Results

Sora@Tf-HMSNs treatment exhibited the strongest inhibition effect of res-TPC-1 cells and res-BCPAP cells compared with sora@HMSNs and sorafenib groups and induced more cancer cell apoptosis. Finally, Western blot analysis was conducted to check the expression of RAF/MEK/ERK signaling pathway after sorafenib encapsulated Tf-HMSNs treatment.

Conclusion

Overall, sora@Tf-HMSNs can significantly increase the effective drug concentration in cancer cells and thus enhance the anticancer effect, which are expected to be promising nanocarriers to deliver anticancer drugs for effective and safe therapy for RAI-refractory DTC.

Antrodia cinnamomea boosts the anti-tumor activity of sorafenib in xenograft models of human hepatocellular carcinoma

Hepatocellular carcinoma (HCC) has been recognized worldwide as one of the major causes of cancer death. The medicinal fungus Antrodia cinnamomea (A. cinnamomea) has been served as a functional food for liver protection. The aim of the present study was to investigate the potential activity of A. cinnamomea extracts as a safe booster for the anticancer activity of sorafenib, a multi-kinase inhibitor approved for the treatment of HCC. The biologically active triterpenoids in the ethanolic extracts of A. cinnamomea (EAC) were initially identified by HPLC/LC/MS then the different extracts and sorafenib were assessed in vitro and in vivo. EAC could effectively sensitize HCC cells to low doses of sorafenib, which was perceived via the ability of the combination to repress cell viability and to induce cell cycle arrest and apoptosis in HCC cells. The ability of EAC to enhance sorafenib activity was mediated through targeting mitogen-activated protein (MAP) kinases, modulating cyclin proteins expression and inhibiting cancer cell invasion. Moreover, the proposed combination significantly suppressed ectopic tumor growth in mice with high safety margins compared to single-agent treatment. Thus, this study highlights the advantage of combining EAC with sorafenib as a potential adjuvant therapeutic strategy against HCC.

Luteolin and sorafenib combination kills human hepatocellular carcinoma cells through apoptosis potentiation and JNK activation

Sorafenib is a small-molecule multi-kinase inhibitor approved by FDA as an oral agent for the treatment of hepatocellular carcinoma (HCC) and renal cell carcinoma. However, unresponsiveness and acquired resistance are commonly observed, which hinder the clinical use of sorafenib. As combination therapy is a promising approach to improve its efficacy, we investigated if sorafenib and luteolin combination is effective in killing human HCC cells. Cell death was examined by lactate dehydrogenase (LDH) releasing assay. Apoptosis was detected by flow cytometric. The activation of apoptotic pathway and c-Jun N-terminal kinase (JNK) signaling pathway was measured by western blot. The results showed that sorafenib and luteolin combination synergistically induced cytotoxicity in HCC cells, which was accompanied by potentiation of apoptosis as demonstrated by increased apoptotic cell populations, caspase activation, and suppression of cell death by the pan-caspase inhibitor z-VAD-fmk. Furthermore, the combination of both agents enhanced expression of phosphorylated form of JNK, and the JNK inhibitor SP600125 effectively attenuated cell death induced by the combination treatment. Thus, sorafenib and luteolin combination synergistically kills HCC cells through JNK-mediated apoptosis, and luteolin may be an ideal candidate for increasing the activity of sorafenib in HCC therapy.

Multicellular spheroids from normal and neoplastic thyroid tissues as a suitable model to test the effects of multikinase inhibitors

Multicellular three-dimensional (3D) spheroids represent an experimental model that is intermediate in its complexity between monolayer cultures and patients’ tumor. In the present study, we characterize multicellular spheroids from papillary (PTC) and follicular (FTC) thyroid cancers and from the corresponding normal tissues. We show that these 3D structures well recapitulate the features of the original tissues, in either the differentiated and “stem-like” components. As a second step, we were aimed to test the effects of a small multikinase inhibitor, SP600125 (SP), previously shown to efficiently induce cell death in undifferentiated thyroid cancer monolayer cultures. We demonstrate the potent effect of SP on cell growth and survival in our 3D multicellular cultures. SP exerts its main effects through direct and highly significant inhibition of the ROCK pathway, known to be involved in the regulation of cell migration and β-catenin turnover. Consistently, SP treatment resulted in a significant decrease in β-catenin levels with respect to basal conditions in tumor but not in normal spheroids, indicating that the effect is promisingly selective on tumor cells.

In conclusion, we provide the morphological and molecular characterization of thyroid normal and tumor spheroids. In this 3D model we tested in vitro the effects of the multikinase inhibitor SP and further characterized its mechanism of action in both normal and tumor spheroids, thus making it an ideal candidate for developing new drugs against thyroid cancer.

Selection of internal references for qRT-PCR assays of human hepatocellular carcinoma cell lines

Selecting internal references is important for normalizing the loading quantity of samples in quantitative reverse-transcription PCR (qRT-PCR). In the present study, a systematic evaluation of reference genes among nine hepatocellular carcinoma (HCC) cell lines was conducted. After screening the microarray assay data of ten HCC cell lines, 19 candidate reference genes were preselected and then evaluated by qRT-PCR, together with ACTB, GAPDH, HPRT1 and TUBB The expression evenness of these candidate genes was evaluated using RefFinder. The stabilities of the reference genes were further evaluated under different experimental perturbations in Huh-7 and MHCC-97L, and the applicability of the reference genes was assessed by measuring the mRNA expression of CCND1, CCND3, CDK4 and CDK6 under sorafenib treatment in Huh-7. Results showed that TFG and SFRS4 are among the most reliable reference genes, and ACTB ranks third and acts quite well as a classical choice, whereas GAPDH, HPRT1 and TUBB are not proper reference genes in qRT-PCR assays among the HCC cell lines. SFRS4, YWHAB, SFRS4 and CNPY3 are the most stable reference genes of the MHCC-97L under the perturbations of chemotherapy, oxidative stress, starvation and hypoxia respectively, whereas YWHAB is the most stable one of Huh-7 under all perturbations. GAPDH is recommended as a reference gene under chemotherapy perturbations. YWHAB and UBE2B, TMED2 and TSFM, and GAPDH and TSFM are the two best reference genes under oxidative stress, starvation and hypoxia perturbations respectively. TSFM is stable in both cell lines across all the perturbations.

Effects of sorafenib and an adenylyl cyclase activator on in vitro growth of well-differentiated thyroid cancer cells

Well-differentiated thyroid carcinomas have driver mutations involving growth factor receptor-tyrosine kinases (RTKs) or their intracellular signaling pathway, that is, the mitogen-activated protein kinase (MAPK) pathway. Sorafenib is a multikinase inhibitor of RTKs and the MAPK pathway and has recently been used for the treatment of unresectable well-differentiated thyroid carcinoma. In normal thyroid follicular cells, stimulation of the thyroid-stimulating hormone (TSH) receptor activates the cyclic adenosine monophosphate (cAMP) pathway and promotes cell growth as well as hormonal secretion. However, an adenylyl cyclase (AC) activator, forskolin, has been reported to suppress the growth of thyroid carcinoma cells. To clarify the roles of the MAPK and cAMP pathways in proliferation of well-differentiated thyroid carcinoma cells, we compared the effects of sorafenib and forskolin in in vitro models. Sorafenib inhibited constitutive activation of the MAPK pathway, cyclin-dependent kinase 4 (CDK4), and phosphorylated retinoblastoma protein (RB) in 3 well-differentiated carcinoma cell lines, but it did not show sufficiently effective suppression of cell growth. Forskolin significantly suppressed the growth of all 3 cell lines and also activated the cAMP pathway and inhibited expression of cyclin D1. Our results suggest that activation of the cAMP pathway could be more potent than activation of the MAPK pathway in suppressing proliferation of well-differentiated thyroid cancer cells. We postulate that the AC activator suppresses growth of thyroid carcinoma cells through undetermined mechanisms.

Enhanced cytotoxic effect of camptothecin nanosponges in anaplastic thyroid cancer cells in vitro and in vivo on orthotopic xenograft tumors

Anaplastic carcinoma of the thyroid (ATC) is a lethal human malignant cancer with median survival of 6 months. To date, no treatment has substantially changed its course, which makes urgent need for the development of novel drugs or novel formulations for drug delivery. Nanomedicine has enormous potential to improve the accuracy of cancer therapy by enhancing availability and stability, decreasing effective doses and reducing side effects of drugs. Camptothecin (CPT) is an inhibitor of DNA topoisomerase-I with several anticancer properties but has poor solubility and a high degradation rate. Previously, we reported that CPT encapsulated in β-cyclodextrin-nanosponges (CN-CPT) increased solubility, was protected from degradation and inhibited the growth of prostate tumor cells both in vitro and in vivo. The aim of this study was to extend that work by assessing the CN-CPT effectiveness on ATC both in vitro and in vivo. Results showed that CN-CPT significantly inhibited viability, clonogenic capacity and cell-cycle progression of ATC cell lines showing a faster and enhanced effect compared to free CPT. Moreover, CN-CPT inhibited tumor cell adhesion to vascular endothelial cells, migration, secretion of pro-angiogenic factors (IL-8 and VEGF-α), expression of β-PIX, belonging to the Rho family activators, and phosphorylation of the Erk1/2 MAPK. Finally, CN-CPT significantly inhibited the growth, the metastatization and the vascularization of orthotopic ATC xenografts in SCID/beige mice without apparent toxic effects in vivo. This work extends the previous insight showing that β-cyclodextrin-nanosponges are a promising tool for the treatment of ATC.

Sorafenib tosylate inhibits directly necrosome complex formation and protects in mouse models of inflammation and tissue injury

Necroptosis contributes to the pathophysiology of several inflammatory, infectious and degenerative disorders. TNF-induced necroptosis involves activation of the receptor-interacting protein kinases 1 and 3 (RIPK1/3) in a necrosome complex, eventually leading to the phosphorylation and relocation of mixed lineage kinase domain like protein (MLKL). Using a high-content screening of small compounds and FDA-approved drug libraries, we identified the anti-cancer drug Sorafenib tosylate as a potent inhibitor of TNF-dependent necroptosis. Interestingly, Sorafenib has a dual activity spectrum depending on its concentration. In murine and human cell lines it induces cell death, while at lower concentrations it inhibits necroptosis, without affecting NF-κB activation. Pull down experiments with biotinylated Sorafenib show that it binds independently RIPK1, RIPK3 and MLKL. Moreover, it inhibits RIPK1 and RIPK3 kinase activity. In vivo Sorafenib protects against TNF-induced systemic inflammatory response syndrome (SIRS) and renal ischemia–reperfusion injury (IRI). Altogether, we show that Sorafenib can, next to the reported Braf/Mek/Erk and VEGFR pathways, also target the necroptotic pathway and that it can protect in an acute inflammatory RIPK1/3-mediated pathology.

The inhibition of FGF receptor 1 activity mediates sorafenib antiproliferative effects in human malignant pleural mesothelioma tumor-initiating cells

Background

Malignant pleural mesothelioma is an aggressive cancer, characterized by rapid progression and high mortality. Persistence of tumor-initiating cells (TICs, or cancer stem cells) after cytotoxic drug treatment is responsible for tumor relapse, and represents one of the main reasons for the poor prognosis of mesothelioma. In fact, identification of the molecules affecting TIC viability is still a significant challenge.

Methods

TIC-enriched cultures were obtained from 10 human malignant pleural mesotheliomas and cultured in vitro. Three fully characterized tumorigenic cultures, named MM1, MM3, and MM4, were selected and used to assess antiproliferative effects of the multi-kinase inhibitor sorafenib. Cell viability was investigated by MTT assay, and cell cycle analysis as well as induction of apoptosis were determined by flow cytometry. Western blotting was performed to reveal the modulation of protein expression and the phosphorylation status of pathways associated with sorafenib treatment.

Results

We analyzed the molecular mechanisms of the antiproliferative effects of sorafenib in mesothelioma TIC cultures. Sorafenib inhibited cell cycle progression in all cultures, but only in MM3 and MM4 cells was this effect associated with Mcl-1-dependent apoptosis. To investigate the mechanisms of sorafenib-mediated antiproliferative activity, TICs were treated with epidermal growth factor (EGF) or basic fibroblast growth factor (bFGF) causing, in MM3 and MM4 cells, MEK, ERK1/2, Akt, and STAT3 phosphorylation. These effects were abolished by sorafenib only in bFGF-treated cells, while a modest inhibition occurred after EGF stimulation, suggesting that sorafenib effects are mainly due to FGF receptor (FGFR) inhibition. Indeed, FGFR1 phosphorylation was inhibited by sorafenib.

Moreover, in MM1 cells, which release high levels of bFGF and showed autocrine activation of FGFR1 and constitutive phosphorylation/activation of MEK-ERK1/2, sorafenib induced a more effective antiproliferative response, confirming that the main target of the drug is the inhibition of FGFR1 activity.

Conclusions

These results suggest that, in malignant pleural mesothelioma TICs, bFGF signaling is the main target of the antiproliferative response of sorafenib, acting directly on the FGFR1 activation. Patients with constitutive FGFR1 activation via an autocrine loop may be more sensitive to sorafenib treatment and the analysis of this possibility warrants further clinical investigation.

Electronic supplementary material

The online version of this article (doi:10.1186/s13287-017-0573-7) contains supplementary material, which is available to authorized users.

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.

Comprehensive Analysis of miRNome Alterations in Response to Sorafenib Treatment in Colorectal Cancer Cells

MicroRNAs (miRNAs) are master regulators of drug resistance and have been previously proposed as potential biomarkers for the prediction of therapeutic response in colorectal cancer (CRC). Sorafenib, a multi-kinase inhibitor which has been approved for the treatment of liver, renal and thyroid cancer, is currently being studied as a monotherapy in selected molecular subtypes or in combination with other drugs in metastatic CRC. In this study, we explored sorafenib-induced cellular effects in Kirsten rat sarcoma viral oncogene homolog olog (KRAS) wild-type and KRAS-mutated CRC cell lines (Caco-2 and HRT-18), and finally profiled expression changes of specific miRNAs within the miRNome (>1000 human miRNAs) after exposure to sorafenib. Overall, sorafenib induced a time- and dose-dependent growth-inhibitory effect through S-phase cell cycle arrest in KRAS wild-type and KRAS-mutated CRC cells. In HRT-18 cells, two human miRNAs (hsa-miR-597 and hsa-miR-720) and two small RNAs (SNORD 13 and hsa-miR-3182) were identified as specifically sorafenib-induced. In Caco-2 cells, nine human miRNAs (hsa-miR-3142, hsa-miR-20a, hsa-miR-4301, hsa-miR-1290, hsa-miR-4286, hsa-miR-3182, hsa-miR-3142, hsa-miR-1246 and hsa-miR-720) were identified to be differentially regulated post sorafenib treatment. In conclusion, we confirmed sorafenib as a potential anti-neoplastic treatment strategy for CRC cells by demonstrating a growth-inhibitory and cell cycle–arresting effect of this drug. Changes in the miRNome indicate that some specific miRNAs might be relevant as indicators for sorafenib response, drug resistance and potential targets for combinatorial miRNA-based drug strategies.

The BH3 mimetic drug ABT-737 induces apoptosis and acts synergistically with chemotherapeutic drugs in thyroid carcinoma cells

BACKGROUND

Patients with dedifferentiated and anaplastic thyroid carcinomas that do not take up radioiodine are resistant to chemotherapeutic treatment and external irradiation and thus are difficult to treat. Direct induction of apoptosis is a promising approach in these apoptosis-resistant tumor cells. The BH3 mimetic ABT-737 belongs to a new class of drugs that target anti-apoptotic proteins of the BCL-2 family and facilitate cell death. The purpose of this study was to investigate the effect of ABT-737 alone or in combination with chemotherapeutic drugs on thyroid carcinoma cell lines.

METHODS

A total of 16 cell lines derived from follicular, papillary, and anaplastic thyroid carcinomas were treated with ABT-737. Cell viability was measured with MTT assay. Cell death was determined by cell cycle phase distribution and subG1 peak analyses, determination of caspase 3/7 activity and caspase cleavage products, lactate dehydrogenase (LDH) liberation assays and LC3 analysis by western blot.

RESULTS

The number of viable cells was decreased in all cell lines examined after ABT-737 treatment, with IC50 values ranging from 0.73 to 15.6 μM. Biochemical markers of apoptosis like caspase activities, caspase cleavage products and DNA fragmentation determined as SubG1 peak were elevated after ABT-737 treatment, but no LC3 cleavage was induced by ABT-737 indicating no autophagic processes. In combination with doxorubicin and gemcitabine, ABT-737 showed synergistic effects on cell viability.

CONCLUSIONS

With these experiments we demonstrated the efficacy of the BH3 mimetic drug ABT-737 against dedifferentiated thyroid carcinoma cells of various histological origins and showed synergistic effects with chemotherapeutic drugs. ABT-737-treated cells underwent an apoptotic cell death. ABT-737 and related BH3 mimetic drugs, alone or in combination, may thus be of value as a new therapeutic option for dedifferentiated thyroid carcinomas.

Novel c-Met inhibitor suppresses the growth of c-Met-addicted gastric cancer cells

BACKGROUND

c-Met signaling has been implicated in oncogenesis especially in cells with c-met gene amplification. Since 20 % of gastric cancer patients show high level of c-Met expression, c-Met has been identified as a good candidate for targeted therapy in gastric cancer. Herein, we report our newly synthesized c-Met inhibitor by showing its efficacy both in vitro and in vivo.

METHODS

Compounds with both triazolopyrazine and pyridoxazine scaffolds were synthesized and tested using HTRF c-Met kinase assay. We performed cytotoxic assay, cellular phosphorylation assay, and cell cycle assay to investigate the cellular inhibitory mechanism of our compounds. We also conducted mouse xenograft assay to see efficacy in vivo.

RESULTS

KRC-00509 and KRC-00715 were selected as excellent c-Met inhibitors through biochemical assay, and exhibited to be exclusively selective to c-Met by kinase panel assay. Cytotoxic assays using 18 gastric cancer cell lines showed our c-Met inhibitors suppressed specifically the growth of c-Met overexpressed cell lines, not that of c-Met low expressed cell lines, by inducing G1/S arrest. In c-met amplified cell lines, c-Met inhibitors reduced the downstream signals including Akt and Erk as well as c-Met activity. In vivo Hs746T xenograft assay showed KRC-00715 reduced the tumor size significantly.

CONCLUSIONS

Our in vitro and in vivo data suggest KRC-00715 is a potent and highly selective c-Met inhibitor which may have therapeutic potential in gastric tumor with c-Met overexpression.

Individualized multimodal treatment strategy for anaplastic thyroid carcinoma-Case report of long-term remission and review of literature

INTRODUCTION

The prognosis of anaplastic thyroid cancer (ATC) is poor with a mean survival time of six months following diagnosis. Despite various attempts to modify common treatment modalities including surgery, external beam radiation and chemotherapy, an effective treatment is not available yet. We report, here, a patient who achieved long-term survival based on multimodal treatment, including in vitro evaluation of drug response of his tumor cells.

PRESENTATION OF CASE

A 42 years old male patient underwent total thyroidectomy with central and lateral neck dissection for ATC (pT4b, pN0 (0/36), L0, V0, Pn1, R0 cM0 - UICC-Stage: IV b). From the tumor tissue a primary cell culture was established. While the patient received a combined radio-chemotherapy cell viability assays were performed using Sorafenib, Vandetanib und MLN8054 (Aurora kinase inhibitor) as inhibitors. Cell viability was determined by MTT-assay after 72 and 144h of treatment.

DISCUSSION

All the three compounds affected cell viability in a time- and dose dependent manner. These effects were most pronounced by Sorafenib. Based on in vitro findings, the patient was treated daily with 400mg Sorafenib for 75days. 43 months after initial diagnosis, the patient had no evidence of disease as shown by MRI, CT and FDG-PET-CT imaging.

CONCLUSION

In the setting of multimodal treatment, in vitro drug evaluation of individual tumor cells of patients might be a promising tool to ameliorate the fatal prognosis of selected ATC patients.

Synergistic effect of fisetin combined with sorafenib in human cervical cancer HeLa cells through activation of death receptor-5 mediated caspase-8/caspase-3 and the mitochondria-dependent apoptotic pathway

Combining antitumor agents with bioactive compounds is a potential strategy for improving the effect of chemotherapy on cancer cells. The goal of this study was to elucidate the antitumor effect of the flavonoid, fisetin, combined with the multikinase inhibitor, sorafenib, against human cervical cancer cells in vitro and in vivo. The combination of fisetin and sorafenib synergistically induced apoptosis in HeLa cells, which is accompanied by a marked increase in loss of mitochondrial membrane potential. Apoptosis induction was achieved by caspase-3 and caspase-8 activation which increased the ratio of Bax/Bcl-2 and caused the subsequent cleavage of PARP level while disrupting the mitochondrial membrane potential in HeLa cells. Decreased Bax/Bcl-2 ratio level and mitochondrial membrane potential were also observed in siDR5-treated HeLa cells. In addition, in vivo studies revealed that the combined fisetin and sorafenib treatment was clearly superior to sorafenib treatment alone using a HeLa xenograft model. Our study showed that the combination of fisetin and sorafenib exerted better synergistic effects in vitro and in vivo than either agent used alone against human cervical cancer, and this synergism was based on apoptotic potential through a mitochondrial- and DR5-dependent caspase-8/caspase-3 signaling pathway. This combined fisetin and sorafenib treatment represents a novel therapeutic strategy for further clinical developments in advanced cervical cancer.

Antisense-miR-21 enhances differentiation/apoptosis and reduces cancer stemness state on anaplastic thyroid cancer

Anaplastic thyroid carcinoma (ATC) is the most aggressive malignancy in thyroid cancers. Resistance to current therapies is still a challenge. MicroRNAs are a class of small non-coding RNAs, regulating gene expression. MiR-21 is an oncomiR that is overexpressed in nearly all cancers including ATC. Accumulating evidence suggested that miR-21 has a role in cancer stemness state, apoptosis, cell cycle progression, and differentiation. Therefore, we evaluated the application of Off-miR-21 to sequester the microRNA for therapeutic purposes on ATC cell lines. In this study, C643 and SW1736 were transducted by hsa-miR-21 antagomir (Off-miR-21). PTEN gene expression was performed as a known target of miR-21. Stemness state in cancer stem cells (CSCs) was evaluated by the changes of CSC biomarkers including Oct-4 and ABCG2. Apoptosis was assessed by PDCD4 and Mcl-1 gene expression and flow cytometry. Sodium/iodide symporter (NIS) and thyroglobulin (TG) were measured as ATC differentiation markers. In addition, cell cycle progression was investigated via the alterations of p21 gene expression and flow cytometry. Specific downregulation of miR-21 induced the differentiation and apoptosis in C643 and SW1736. Inversely, the treatment inhibited stemness state and cell cycle progression. Knockdown of miR-21 significantly increased the expression of PDCD4, p21, NIS, and TG while leading to decreased expression of Oct-4, ABCG2, and Mcl-1.Taken together, the results suggest that miR-21, as an oncomiR, has a role not only in stemness state but also in tumor growth, differentiation, and apoptosis. Hence, suppression of miR-21 could pave the way for ATC therapy.

Cell death induction by the BH3 mimetic GX15-070 in thyroid carcinoma cells

Background

The evasion of cell death is one of the hallmarks of cancer, contributing to both tumor progression and resistance to therapy. Dedifferentiated and anaplastic thyroid carcinomas that do not take up radioiodine are resistant to conventional anticancer treatments and patients with these tumors are difficult to treat. BH3 mimetics are a new class of drugs that target anti-apoptotic proteins of the BCL-2 family and promote cell death. The purpose of this study was to analyze the molecular effects of the BH3 mimetic GX15-070 on thyroid carcinoma cell lines and to characterize cell death induced by GX15-070.

Methods

A total of 17 cell lines derived from follicular, papillary, and anaplastic thyroid carcinomas were treated with GX15-070. Cell viability was measured with MTT assay while cell cycle phase distribution and subG1 peaks were determined after propidium iodide staining. We assessed cell death via the caspase 3/7 activity, caspase cleavage products, lactate dehydrogenase (LDH) liberation assays, and a LC3 analysis by western blot. Ultrastructural changes were analysed by electron microscopy of GX15-070-treated cells.

Results

After GX15-070 treatment, the number of viable cells was decreased in all cell lines examined, with IC50 values ranging from 48nM to 3.25 μM. We observed biochemical markers of autophagic cell death and necrosis like LC3 conversion and LDH release after the GX15-070 treatment. Electron microscopy revealed several common characteristic ultrastructural changes like swelling of mitochondria, dilatation of rough endoplasmic reticulum, membrane blebbing and formation of vacuoles. GX15-070 treatment induced DNA fragmentation detected by subG1-peak induction and an arrest in G1 phase of the cell cycle. Caspase activation after GX15-070 incubation was detected but had no effect on viability of cells.

Conclusions

With these experiments we demonstrated the efficacy of the BH3 mimetic drug GX15-070 acting against dedifferentiated thyroid carcinoma cells of various histological origins by the induction of cell death. GX15-070-treated cells underwent non-classical cell death with signs of apoptosis, autophagy and necrosis in parallel. GX15-07 and related compounds thus may be a new therapeutic option for dedifferentiated thyroid carcinoma of various histological subtypes.