Anaplastic thyroid cancer (ATC) is a lethal human cancer with a 5-year survival rate of less than 10%. Recently, its genomic and transcriptomic characteristics have been extensively elucidated over 5 years owing to advance in high throughput sequencing. These efforts have extended molecular understandings into the progression mechanisms and therapeutic vulnerabilities of aggressive thyroid cancers. In this review, we provide an overview of genomic and transcriptomic alterations in ATC and poorly-differentiated thyroid cancer, which are distinguished from differentiated thyroid cancers. Clinically relevant genomic alterations and deregulated signaling pathways will be able to shed light on more effective prevention and stratified therapeutic interventions for affected patients.
Citations
Anaplastic thyroid cancer (ATC) is one of the most lethal human malignancies. Docetaxel, a microtubule stabilizer, is a common chemotherapeutic agent used to treat various metastatic cancers. However, prolonged use results in various side effects and drug resistance. Flavonoids, such as baicalein, are accepted chemotherapeutic and dietary chemopreventive agents with many advantages, such as greater accessibility, affordability, and lower toxicity, compared with traditional chemotherapy agents. In this study, we evaluated whether baicalein enhances the effects of docetaxel on apoptosis and metastasis in 8505c ATC cells.
The 8505c cells were treated with baicalein or docetaxel individually and in combination. Cell viability was measured by MTT (thiazolyl blue tetrazolium bromide) assay, and apoptosis was detected by fluorescence microscopy of Hoechst-stained cells. The expression of apoptotic (Bax and caspase-3), anti-apoptotic (Bcl-2), angiogenic (vascular endothelial growth factor [VEGF], transforming growth factor β [TGF-β], E-cadherin, and N-cadherin), and signaling (extracellular signal-regulated kinase [ERK] mitogen activated protein kinase [MAPK], Akt, and mammalian target of rapamycin [mTOR]) proteins was determined by Western blot analysis.
The combination of baicalein (50 or 100 µM) and docetaxel (10 nM) significantly inhibited proliferation and induced apoptosis compared with monotherapies. The combination treatment significantly inhibited the expression of Bax, caspase-3, VEGF, TGF-β1, E-cadherin, N-cadherin, and mTOR, but decreased the expression of Bcl-2 and significantly decreased the phosphorylation of ERK and Akt.
The combination of baicalein and docetaxel effectively induced apoptosis and inhibited metastasis in 8505c cells through downregulation of apoptotic and angiogenic protein expression and blocking of the ERK and Akt/mTOR pathways in 8505c cells. These results suggest that baicalein enhances the anticancer effects of docetaxel in ATC.
Citations
Tumor associated macrophages (TAMs) and CXC chemokine receptor 4 (CXCR4) have emerged as potential biomarkers in various human cancers. The aims of this study were to investigate the clinical characteristics of anaplastic thyroid cancer (ATC) patients according to the TAM numbers in the tumor tissue, and to evaluate the associations between CXCR4 expressions and macrophage densities in ATC tumor microenvironment.
Total 14 ATC samples from thyroid tissue microarray were used. Immunohistochemical staining was performed using anti-CD163 and anti-CXCR4 antibodies. According to the immunoreactivity of CD163, all subjects were divided into two groups: low-CD163 (
The mean diagnostic age was 65±7 years and the median tumor size was 4.3 cm, ranging 2.5 to 15 cm. Clinicopathological characteristics were not significantly different between low-CD163 and high-CD163 groups, while age of diagnosis was younger in high-CD163 group than that of low-CD163 group with marginal significance (56.9±5.5 years vs. 67.5±6.8 years,
Increased number of TAMs showed poor overall survival in ATC, suggesting TAMs are potentially a prognostic biomarker for ATC. CXCR4 expression was significantly correlated with CD163-positive TAM densities, which suggest the possible role of CXCR4 in TAM recruitments.
Citations