Control of nuclear size by NPC proteins

High-Resolution Microscopy to Learn the Nuclear Organization of the Living Yeast Cells

The spatial organization of the nucleus is a key determinant in all genome activities. However, the accurate measurement of the nuclear organization is still technically challenging. Here, the technology NucQuant we created previously was utilized to detect the variation of the nuclear organization, including the heterogeneity of the nuclear geometry, the change of the NPC distribution along different cell cycle stages during interphase, and the organization of the nucleolus. The results confirmed that not only the growth rate and the NPC distribution are influenced by the carbon source; the nuclear shape is also impacted by the carbon source. The nuclei lost their spherical geometry gradually when the cell was cultured from the most to a less favorable carbon source. We also discovered that the nucleolus prefers to locate at the nuclear periphery, which was called the "genes poor region," especially when the cells entered quiescence. Furthermore, the distribution of the NPC along the different stages during the interphase was analyzed. We proposed that with the growth of the cell, the nucleus would grow from the surface of the NE flanking the nucleolus firstly.

Membrane Lipid Composition: Effect on Membrane and Organelle Structure, Function and Compartmentalization and Therapeutic Avenues

Biological membranes are key elements for the maintenance of cell architecture and physiology. Beyond a pure barrier separating the inner space of the cell from the outer, the plasma membrane is a scaffold and player in cell-to-cell communication and the initiation of intracellular signals among other functions. Critical to this function is the plasma membrane compartmentalization in lipid microdomains that control the localization and productive interactions of proteins involved in cell signal propagation. In addition, cells are divided into compartments limited by other membranes whose integrity and homeostasis are finely controlled, and which determine the identity and function of the different organelles. Here, we review current knowledge on membrane lipid composition in the plasma membrane and endomembrane compartments, emphasizing its role in sustaining organelle structure and function. The correct composition and structure of cell membranes define key pathophysiological aspects of cells. Therefore, we explore the therapeutic potential of manipulating membrane lipid composition with approaches like membrane lipid therapy, aiming to normalize cell functions through the modification of membrane lipid bilayers.

High expression of IMPDH2 is associated with aggressive features and poor prognosis of primary nasopharyngeal carcinoma

Inosine monophosphate dehydrogenase type II (IMPDH2) has been shown to play critical roles in the development and progression of several human cancers. However, little is known about IMPDH2 expression and its clinical significance in nasopharyngeal carcinoma (NPC). Western blotting, qRT-PCR and immunohistochemistry were employed to evaluate IMPDH2 expression in NPC cell lines and tissues. In our study, elevated expression of IMPDH2 was observed at both the protein and mRNA levels in NPC cell lines than in NPEC2 Bmi-1. IMPDH2 protein expression was markedly higher in NPC tissues than in adjacent non-tumorous tissues. Moreover, IMPDH2 expression in NPC correlated with several clinicopathological parameters, including T classification (P = 0.023), TNM stage (P = 0.020), distant metastasis (P = 0.001) and death (P = 0.002). Further Cox regression analysis suggested that IMPDH2 expression was an independent prognostic factor for overall survival (P = 0.001) and disease-free survival (P < 0.001). In addition, stratified survival analysis showed that high expression of IMPDH2 could be a prognostic factor for NPC patients with TNM stage I/II (OS: P = 0.012; DMFS: P = 0.007), TNM stage III/IV (OS: P = 0.028; DMFS: P = 0.020). Our study demonstrates IMPDH2 may be served as an independent prognostic biomarker for NPC patients, in which high IMPDH expression suggests poor prognosis of NPC patients.

Low expression of Aldo-keto reductase 1B10 is a novel independent prognostic indicator for nasopharyngeal carcinoma

Background

Nasopharyngeal carcinoma (NPC) is one of the most common human head and neck cancers with high incidence in Southern China, Southeast Asia and North Africa. Because of its nonspecific symptoms, the early diagnosis of NPC is very difficult. The 5-year survival rate is not ideal in spite of great innovations in radiation and chemotherapy treatments. Highly sensitive and specific prognostic biomarkers are eager for NPC clinical diagnosis. To find specific target molecules is very important for individualized treatment. Aldo–keto reductase B10 (AKR1B10) is closely related to tumorigenesis and tumor development, and however, its expression level in NPC tissues is not clear.

Results

AKR1B10 expression levels were validated in benign, para-cancerous nasopharyngeal and NPC tissues by immunohistochemical evaluation. AKR1B10 was positively expressed in 42 (82.4 %) of 51 benign specimens, and 235 (98.7 %) of 238 para-carcinoma specimens. This percentage was significantly higher than 44.5 % (133/299) in nasopharyngeal carcinoma tissue (p < 0.01). AKR1B10 mRNA quantitative levels detected by real-time quantitative RT-PCR in 90 NPC tissue samples (0.10 ± 0.21) were significantly lower than that in 15 benign tissue samples (1.03 ± 1.12) (p < 0.01). AKR1B10 expression levels in NPC were correlated negatively with T-classification, lymph node metastasis (p < 0.05). We established nasopharyngeal cancer monoclonal cells CNE-2/AKR1B10 with AKR1B10 stable expression and CNE-2/vector cells without AKR1B10 expression by using a modified lentivirus-mediated method, and found that AKR1B10 inhibited the proliferation of CNE-2/AKR1B10 cells by using MTT assay and flow cytometry, and cell migration by in vitro scratch test.

Conclusion

Taken together, our data suggest that low expression of AKR1B10 is an independent prognostic indicator in nasopharyngeal carcinoma, and that AKR1B10 may be involved in regulating the proliferation and migration of nasopharyngeal cancer cells.