Immortalization up‐regulated protein promotes tumorigenesis and inhibits apoptosis of papillary thyroid cancer

The incidence of thyroid cancer is increasing in recent years worldwide, but the underlying mechanisms await further exploration. We utilized the bioinformatic analysis to discover that Immortalization up‐regulated protein (IMUP) could be a potential oncogene in the papillary thyroid cancer (PTC). We verified this finding in several databases and locally validated cohorts. Clinicopathological features analyses showed that high expression of IMUP is positively related to malignant clinicopathological features in PTC. Braf‐like PTC patients with higher IMUP expression had shorter disease‐free survival. The biological function of IMUP in PTC cell lines (KTC‐1 and TPC‐1) was investigated using small interfering RNA. Our results showed that silencing IMUP suppresses proliferation, migration and invasion while inducing apoptosis in PTC cell lines. Changes of the expression of apoptosis‐related molecules were identified by real‐time quantitative polymerase chain reaction and Western blotting. We also found that YAP1 and TAZ, the critical effectors in the Hippo pathway, were down‐regulated when the IMUP is silenced. Rescue experiments showed that overexpression of YAP1 reverses the tumour inhibitory effect caused by IMUP knockdown. Our study demonstrated that IMUP has an oncogenic function in PTC and might be a new target gene in the treatment of PTC.     

ATM regulates Cdt1 stability during the unperturbed S phase to prevent re-replication

Ataxia-telangiectasia mutated (ATM) plays crucial roles in DNA damage responses, especially with regard to DNA double-strand breaks (DSBs). However, it appears that ATM can be activated not only by DSB, but also by some changes in chromatin architecture, suggesting potential ATM function in cell cycle control. Here, we found that ATM is involved in timely degradation of Cdt1, a critical replication licensing factor, during the unperturbed S phase. At least in certain cell types, degradation of p27^Kip1 was also impaired by ATM inhibition. The novel ATM function for Cdt1 regulation was dependent on its kinase activity and NBS1. Indeed, we found that ATM is moderately phosphorylated at Ser1981 during the S phase. ATM silencing induced partial reduction in levels of Skp2, a component of SCF^Skp2 ubiquitin ligase that controls Cdt1 degradation. Furthermore, Skp2 silencing resulted in Cdt1 stabilization like ATM inhibition. In addition, as reported previously, ATM silencing partially prevented Akt phosphorylation at Ser473, indicative of its activation, and Akt inhibition led to modest stabilization of Cdt1. Therefore, the ATM-Akt-SCF^Skp2 pathway may partly contribute to the novel ATM function. Finally, ATM inhibition rendered cells hypersensitive to induction of re-replication, indicating importance for maintenance of genome stability.     

Proteomic detection of cancer in asbestosis patients using SELDI-TOF discovered serum protein biomarkers

Objectives: To identify biomarkers for cancer in asbestosis patients.

Methods: SELDI-TOF and CART were used to identify serum biomarker profiles in 35 asbestosis patients who subsequently developed cancer and 35 did not develop cancer.

Results: Three polypeptide peaks (5707.01, 6598.10, and 20,780.70?Da) could predict the development of cancer with 87% sensitivity and 70% specificity. The first two peaks were identified as KIF18A and KIF5A, respectively, and are part of the Kinesin Superfamily of proteins.

Conclusions: We identified two Kinesin proteins that can be potentially used as blood biomarkers to identify asbestosis patients at risk of developing lung cancer.     

AHNAK controls 53BP1-mediated p53 response by restraining 53BP1 oligomerization and phase separation

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Beyond NF-κB activation: nuclear functions of IκB kinase α

IκB kinase (IKK) complex, the master kinase for NF-κB activation, contains two kinase subunits, IKKα and IKKβ. In addition to mediating NF-κB signaling by phosphorylating IκB proteins during inflammatory and immune responses, the activation of the IKK complex also responds to various stimuli to regulate diverse functions independently of NF-κB. Although these two kinases share structural and biochemical similarities, different sub-cellular localization and phosphorylation targets between IKKα and IKKβ account for their distinct physiological and pathological roles. While IKKβ is predominantly cytoplasmic, IKKα has been found to shuttle between the cytoplasm and the nucleus. The nuclear-specific roles of IKKα have brought increasing complexity to its biological function. This review highlights major advances in the studies of the nuclear functions of IKKα and the mechanisms of IKKα nuclear translocation. Understanding the nuclear activity is essential for targeting IKKα for therapeutics.     

Targeting respiratory complex I to prevent the Warburg effect

In the last 10 years, studies of energetic metabolism in different tumors clearly indicate that the definition of Warburg effect, i.e. the glycolytic shift cells undergo upon transformation, ought to be revisited considering the metabolic plasticity of cancer cells. In fact, recent findings show that the shift from glycolysis to re-established oxidative metabolism is required for certain steps of tumor progression, suggesting that mitochondrial function and, in particular, respiratory complex I are crucial for metabolic and hypoxic adaptation. Based on these evidences, complex I can be considered a lethality target for potential anticancer strategies. In conclusion, in this mini review we summarize and discuss why it is not paradoxical to develop pharmacological and genome editing approaches to target complex I as novel adjuvant therapies for cancer treatment.This article is part of a Directed Issue entitled: Energy Metabolism Disorders and Therapies.     

Association of interleukin‐27 gene polymorphisms with susceptibility to HIV infection and disease progression

Interleukin‐27 (IL‐27) gene polymorphisms are linked to infectious disease susceptibility and IL‐27 plasma level is associated with HIV infection. Therefore, we aimed to investigate the association between IL‐27 polymorphisms and susceptibility to HIV infection and disease progression. A total of 300 patients with HIV infection (48 long‐term nonprogressors and 252 typical progressors) and 300 healthy controls were genotyped for three IL‐27 polymorphisms, rs17855750, rs181206, rs40837 which were performed by using multiple single nucleotide primer extension technique. Significant association was found between IL‐27 rs40837 polymorphisms with susceptibility to HIV infection (AG vs AA: adjusted OR = 1.60, 95% CI, 1.11‐2.30, P = 0.012; AG+GG vs AA: adjusted OR = 1.44, 95% CI, 1.02‐2.03, P = 0.038) and disease progression (LTNP: AG vs AA: adjusted OR = 2.33, 95% CI, 1.13‐4.80, P = 0.021; TP: AG vs AA: adjusted OR = 1.50, 95% CI, 1.04‐2.24, P = 0.030). Serum IL‐27 levels were significantly lower in cases compared to controls (P < 0.001). There were lower serum IL‐27 levels in TPs than in LTNPs (P < 0.001). We further found that LTNPs with rs40837 AG or GG genotype had lower serum IL‐27 levels than with AA genotype (P < 0.05). The CD4⁺T counts in cases were significantly lower than controls (P < 0.001). In contrast, individuals with rs40837 AG genotype had lower CD4⁺T counts than with AA genotype in cases (P < 0.05). In addition, CD4⁺T counts in TPs were significantly lower than LTNPs (P < 0.001). IL‐27 rs40837 polymorphism might influence the susceptibility to HIV infection and disease progression probably by regulating the level of serum IL‐27 or the quantity of CD4⁺T.     

Headcase and Unkempt Regulate Tissue Growth and Cell Cycle Progression in Response to Nutrient Restriction

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