Cell metabolism abnormalities are closely related to tumor occurrence and development. Fatty acid synthase (FASN) is the key molecule for catalyzing fatty acid synthesis. Increasing evidence indicates that FASN is highly expressed in a number of malignant tumors; it can promote the synthesis of endogenous fatty acids in tumor cells and then the synthesized fatty acids provide energy for the proliferation of tumor cells. However, there has been no systematic study focusing on FASN expression and function in hepatocellular carcinoma (HCC). The aim of the present study was to verify the high expression of FASN in HCC cells at the histological and cellular levels, and to construct FASN shRNA eukaryotic expression vector for interfering FASN expression in HCC cell line SK-Hep-1, in an effort to explore the role of FASN in the proliferation, apoptosis, invasion and migration of HCC cells. In the present study, we demonstrated that FASN was highly expressed in HCC tissues compared with tumor-adjacent tissue and normal liver cell line 7702 (P<0.05). FASN expression in the high metastatic MHCC97H and SK-Hep-1 cell lines was increased compared with low metastatic HCC cell lines (P<0.05). Then, we constructed a FASN shRNA eukaryotic expression vector; after HCC SK-Hep-1 cells were transfected, the cell proliferation, migration and invasion were inhibited, but FASN had no impact on the apoptosis of HCC cells. Collectively, these data indicate that FASN is possibly involved in the occurrence and metastasis of HCC. Thus, inhibition of FASN may be a promising approach for the treatment of HCC.

Van der Waals (vdWs) heterostructures based on 2D metals and semiconductors have attracted considerable attention due to their excellent properties and great application potential in next-generation electronic and optoelectronic devices. To obtain such vdWs heterostructures, the conventional approach with artificial exfoliation and stacking of 2D metals onto 2D semiconductors in the vertical direction is still far from satisfactory, because of the low yield and impurity-involved transfer process. Here, two-step vapor deposition growth of 2D TaSe 2 -MoSe 2 metal-semiconductor heterostructures is reported. Raman maps confirm the precise spatial modulation of the as-grown 2D TaSe 2 -MoSe 2 heterostructures. Structural analysis reveals that the upper 1T-TaSe 2 is formed heteroepitaxially on/around the presynthesized 2H-MoSe 2 monolayers with an epitaxial relationship of (10-10) TaSe2 //(10-10) MoSe2 and [0001] TaSe2 //[0001] MoSe2 . Based on the detailed characterizations of morphology, structure, and composition, an edge-induced growth mechanism is proposed to illustrate the formation process of the 2D heterostructures, confirmed by first-principle calculations. In addition, Kelvin probe force microscope characterizations and electrical transport measurements confirm that the 2D metal-semiconductor heterostructures exhibit typical rectification characteristics with a contact potential height of ≈431 mV. The direct growth of high-quality 2D metal-semiconductor heterostructures marks an important step toward high-performance integrated optoelectronic devices.

Synthesis of high-quality ZnO/ZnS heterostructures with tunable phase and controlled structures is in high demand due to their adjustable band gap and efficient electron-hole pair separation. In this report, for...