The ubiquitin system, known as a common feature in eukaryotes, participates in multiple cellular processes, such as signal transduction, cell-cycle progression, receptor trafficking and endocytosis, and even the immune response. In lung cancer, evidence has revealed that aberrant events in ubiquitin-mediated processes can cause a variety of pathological outcomes including tumorigenesis and metastasis. Likewise, ubiquitination on the core components contributing to the activity of cell signaling controls bio-signal turnover and cell final destination. Given this, inhibitors targeting the ubiquitin system have been developed for lung cancer therapies and have shown great prospects for clinical application. However, the exact biological effects and physiological role of the drugs used in lung cancer therapies are still not clearly elucidated, which might seriously impede the progress of treatment. In this work, we summarize current research advances in cell signal regulation processes mediated through the ubiquitin system during the development of lung cancer, with the hope of improving the therapeutic effects by means of aiming at efficient targets.

PurposeThe purpose of this study is to explore the prognostic value of associating pre-treatment neutrophil–lymphocyte ratio (NLR) with circulating tumor cells counts (CTCs) in patients with gastrointestinal cancer.Materials and MethodsWe collected the related data of 72 patients with gastric cancer (GC) and colorectal cancer (CRC) who received different therapies from August 2016 to October 2020, including age, gender, primary tumor location, TNM stage, tumor-differentiation, NLR, CTCs, disease-free survival (DFS) and overall survival (OS). We chose the optimal cut-off value of NLR >3.21 or NLR ≤3.21 and CTC >1 or CTC ≤1 by obtaining receiver operating characteristic (ROC) curve. The Kaplan–Meier survival analysis and Cox regression analysis were used to analyze DFS and OS. To clarify the role of the combination of NLR and CTCs counts in predicting the prognosis, we analyzed the DFS and OS when associated NLR and CTCs counts.ResultsA high NLR (>3.21) was associated with shorter DFS (P <0.0001) and OS (P <0.0001). Patients with high CTCs level (>1) had shorter DFS (P = 0.001) and OS (P = 0.0007) than patients with low CTCs level. Furthermore, patients who had both higher NLR and higher CTCs counts had obvious shorter DFS (P <0.0001) and OS (P <0.0001).ConclusionsPatients with higher NLR and more CTCs respectively tended to have poor prognosis with shorter DFS and OS, which might be regarded as predictors of gastrointestinal cancer. In particular, associating NLR and CTCs counts might be a reliable predictor in patients with gastrointestinal cancer.

SUMOylation is an important post-translational modification that participates in a variety of cellular physiological and pathological processes in eukaryotic cells. Sirt2, a NAD + -dependent deacetylase, usually exerts a tumor-suppressor function. However, the role of SUMOylation in cancer cells is not fully known. In this study, we found that SUMOylation can occur in the Sirt2 protein at both lysine 183 and lysine 340 sites. SUMOylation did not affect Sirt2 localization or stability but was involved in P38-mTORC2-AKT cellular signal transduction via direct deacetylation on a new substrate MAPK/P38. SUMOylation-deficient Sirt2 lost the capability of suppressing tumor processes and showed resistance to the Sirt2-specific inhibitor AK-7 in neuroblastoma cells. Here, we revealed the important function of Sirt2-SUMOylation, which is closely associated with cellular signal transduction and is essential for suppressing tumorigenesis in neuroblastoma.

No abstract