Rapamycin inhibits the invasive ability of thyroid cancer cells by down-regulating the expression of VEGF-C in vitro

Comprehensive analysis of the clinical significance and prospective molecular mechanisms of differentially expressed autophagy-related genes in thyroid cancer

Thyroid cancer (TC) is the most common endocrine malignancy, accounting for approximately 90% of all malignancies of the endocrine system. Despite the fact that patients with TC tend to have good prognoses, the high incidence rate and lymph node metastases remain unresolved issues. Autophagy is an indispensable process that maintains intracellular homeostasis; however, the role of autophagy in several steps of the initiation and progression of TC has not yet been elucidated. In this study, we first identified several autophagy-related genes (ARGs) that were provoked in the onset of TC. Subsequently, a bioinformatics analysis hinted that these genes were markedly disturbed in several proliferative signaling pathways. Moreover, we demonstrated that the differentially expressed ARGs were closely related to several aggressive clinical manifestations, including an advanced tumor stage and lymph node metastasis. Our study further selected prognostic ARGs and developed a prognostic signature based on three key genes (ATG9B, BID and B1DNAJB1), which displayed a moderate ability to predict the prognosis of TC. On the whole, the findings of this study demonstrate that ARGs disrupt proliferation-related pathways and consequently lead to aggressive clinical manifestations. These findings provide insight into the potential molecular mechanisms of action of ARGs and their clinical significance, and also provide classification information of potential therapeutic significance.

Coexpressed High Levels of VEGF-C and Active MMP-9 Are Associated With Lymphatic Spreading and Local Invasiveness of Papillary Thyroid Carcinoma

OBJECTIVES

Papillary thyroid carcinoma (PTC) usually has a good prognosis, but some patients develop an aggressive course of the disease, leading to a poor outcome. Vascular endothelial growth factor C (VEGF-C) and matrix metalloproteinase 9 (MMP-9) have been shown to play roles in tumor progression in various human malignancies.

METHODS

We analyzed VEGF-C and active MMP-9 expression profiles in PTC samples using immunohistochemistry and Western blotting.

RESULTS

Immunohistochemistry showed positive staining for VEGF-C and active MMP-9 in 83% and 57% of PTCs, respectively (n = 60), with a positive correlation between their expression levels (Spearman, P < .001). Concomitant high expression of VEGF-C and active MMP-9 correlated with the presence of lymph node metastasis (P  = .005), pT status (P  = .004), pTNM tumor stage (P  = .005), and particularly the degree of tumor infiltration (P < .001, Fisher exact test). Densitometric analysis of Western blot bands confirmed correlation between VEGF-C and active MMP-9 expression (Wilcoxon and Spearman tests) and significant association with the clinicopathologic parameters (Mann-Whitney and Kruskal-Wallis tests).

CONCLUSIONS

Association of coexpressed high levels of VEGF-C and active MMP-9 with lymphatic spreading and local invasiveness of PTC suggests their potential usefulness as predictive biomarkers of aggressive PTC behavior.

Autophagy in thyroid cancer: present knowledge and future perspectives

Thyroid cancer is the most common endocrine malignancy. Despite having a good prognosis in the majority of cases, when the tumor is dedifferentiated it does no longer respond to conventional treatment with radioactive iodine, the prognosis worsens significantly. Treatment options for advanced, dedifferentiated disease are limited and do not cure the disease. Autophagy, a process of self-digestion in which damaged molecules or organelles are degraded and recycled, has emerged as an important player in the pathogenesis of different diseases, including cancer. The role of autophagy in thyroid cancer pathogenesis is not yet elucidated. However, the available data indicate that autophagy is involved in several steps of thyroid tumor initiation and progression as well as in therapy resistance and therefore could be exploited for therapeutic applications. The present review summarizes the most recent data on the role of autophagy in the pathogenesis of thyroid cancer and we will provide a perspective on how this process can be targeted for potential therapeutic approaches and could be further explored in the context of multimodality treatment in cancer and personalized medicine.

Electrical stimuli improve osteogenic differentiation mediated by aniline pentamer and PLGA nanocomposites

Electrical stimulation may improve the proliferation of animal cells. In the present study, osteoblasts were cultured on electroactive aniline pentamer (AP)/poly(lactic-co-glycolic acid) (PLGA) copolymer composites, on which electric pulse was imposed. The combination of polymer and electric pulse enhanced the osteogenic differentiation of the osteoblasts, characterized by the upregulated expression of bone morphogenetic protein (BMP)-2, collagen I and osteonectin and the phosphorylation of Samd4, in contrast to polymer or electrical pulse alone. This action occurred in a polymer content-dependent manner. Therefore, the action of the electric pulse, assisted by the electroactive polymer implant, may be promising in the expedition of injured bone repair.