ABSTRACT
Most diploid cells proliferate by proceeding through the canonical G1 (DNA pre-synthesis), S (DNA synthesis), G2 (DNA post-synthesis), and M(mitosis) phases of the cell cycle. However, there is another type of cell cycle that occurs frequently in both plants and animals, known as endoreplication. Endoreplication consists of alternating periods of G and S phases without cytokinesis, which results in polyploidy. It is indispensable for normal development, organ formation, and wound healing in humans. In recent years, con-siderable attention has been paid to delineating the connections of endoreplication with tumorigenesis and tumor progression. Here, we review the role of endoreplication in normal human development and discuss its possible role in tumor development and the un-derlying molecular mechanisms.
ABSTRACT
Objective:To investigate the inhibitory effect of Dickkopf-1 (Dkk1) on vasculogenic mimicry (VM) formation and the relevant mechanism. Methods:CD34-PAS dual staining and immunohistochemical staining were used to detect and analyze the re-lationship between VM existence and Dkk1 expression in 217 human colon cancer tissue samples;three dimensional (3D) culture was used to detect the influence of Dkk1 on tube structure formation and on VE-cadherin expression;a subcutaneous mouse xenograft mod-el was made to further validate the inhibitory role of Dkk1 on VM formation in vivo. Results:VM-positive samples indicated a lower expression of Dkk1(P<0.05);colon cancer cells with Dkk1 overexpression exhibited a decreased ability to form tube-like structure and a decreased expression of VE-cadherin;Dkk1 inhibited the VM-formation abilities of human colorectal carcinoma cell line xenograft tu-mor tissue. Conclusion:Dkk1 inhibits the VM formation of colon cancer.
ABSTRACT
Given the unlimited proliferation and aerobic glycolysis in tumor cells, these cells require more glucose, glutamine, and other nutrients compared with normal cells. Tumor cells are often affected by insufficient nutrient supply. However, by sensing changes in the nutrient supply in tumor microenvironment and by regulating signal-transduction pathways, some specific proteins can help tumor cells in blocking the cell cycle, reprogramming metabolism, and regulating autophagy to progress and survive against nutri-ent stress. Exciting innovations have been made to elucidate the mechanisms relevant to this process. This review aims to highlight re-cent studies on the mechanisms of sensing the low nutrient supply in microenvironments, as well as the downstream effect factors in cancer cells.
ABSTRACT
Objective:To analyze the clinico-pathological characteristics, pathological diagnosis, and treatment of rhabdoid tu-mor. Methods:The medical records of four rhabdoid tumor patients that were admitted to the Tianjin Medical University Cancer Insti-tute and Hospital since 2000 were analyzed based on existing literature. Results:In one of the four cases, the tumor originated from the kidney, whereas in the other three, the tumor occurred from extra-renal soft tissues. Histologic analysis revealed that the tumor cells were loosely arranged with diffuse growth, vesicular nuclei, dyed cytoplasm, visible eosinophilic inclusions, and more nuclear fission. The results of immunohistochemical staining showed that the vimentin and epithelial membrane antigen were positive, whereas CK, CD99, CD34, and S-100 were positive at different degrees. MyoD1, Desmin, and INI-1 were negative. Conclusion:Rhabdoid tumor is rare and highly aggressive. It occurs mainly in the kidney and can also be found in other systems. The unique pathological form and im-munohistochemical staining observed on the tumor can be used as reference for diagnosis.
ABSTRACT
Objective:This study aims to investigate the potential of colon cancer cells to differentiate into vascular endothelial cells in endothelial-induced specific environment. Methods:Three colon cancer cells with different differentiated level HCT116 (poor-ly differentiated), SW480 (moderately differentiated), HT29 (well differentiated) were cultured in the conditioned medium containing the endothelial-inducing factors for 15 days respectively. The expression of vascular endothelial indicators Platelet endothelial cell adhe-sion molecule-1、Endothelial cell adhesion molecule CD34 was detected via western blot. Immunofluorescence staining was performed to examine CD31 and CD34 expression level in HCT116 after cultured in endothelial-inducing medium and ordinary medium for 15 days respectively, and the three-dimensional (3D) culture was used to detect the abililty of in vitro tube-like structure formation. Re-sults:Western blot showed that CD31 and CD34 expression level were negatively correlated with degree of differentiation in colon can-cer cells. CD31 and CD34 expression in endothelial-inducing medium HCT116 cells (poorly differentiated) were higher then in the nor-mal medium, while the CD31 and CD34 expression in SW480 cells (moderately differentiated) and HT29 cells (well differentiated) in the two cultural mediums were not notably changed. Immunofluorescence staining illustrated that CD31 and CD34 expression in HCT116 cells cultured in endothelial-inducing medium increased compared with those cultured in ordinary medium. In vitro three-di-mensional culture demonstrated that ability of tube-like structure formation was notably enhanced after endothelial-inducing cultured. Conclusion:Endothelial-inducing medium could promote colon cancer cells with strong stemness differentiate toward vascular endo-thelial cells.