Background: The Hippo pathway functions as a tumor suppressor pathway in human cancers, while dysfunction of the Hippo pathway is frequently observed in malignancies. Although YAP/TAZ activity is tightly controlled by the phosphorylation cascade of the MST-LATS-YAP/TAZ axis, it is still unclear why the YAP/TAZ proteins are activated in human cancers despite Hippo pathway activation. Recent studies have suggested that in addition to phosphorylation, several other posttranslational modifications, including ubiquitination, also play critical roles in modulating TAZ function.Methods: We used several gastric cancer cell lines and performed western blot analysis, real-time PCR, immunoprecipitation assays, and in vitro ubiquitination assays and established a xenograft mouse model.Results: Here, by screening a DUB (deubiquitinase) siRNA library, we discovered that DUB1 functions as a critical modulator that facilitates gastric cancer stemness and progression by deubiquitinating and activating the TAZ protein. We also found that DUB1 expression was elevated in gastric cancer and that elevated DUB1 expression correlated with TAZ activation and poor survival. DUB1 associates with the TAZ protein and deubiquitinates TAZ at several lysine residues, which subsequently stabilizes TAZ and facilitates its function.Conclusions: Our study revealed a novel deubiquitinase in the Hippo/TAZ axis and identified one possible therapeutic target for Hippo-driven gastric cancer.

Breast cancer is the leading cause of females characterized by high invasive potential. It is necessary to explore the underlying mechanism of breast cancer metastases and to find specific therapeutic targets. PKM2 is considered a new biomarker of cancer with upregulated expression in tumor tissue. PKM2 participates in the cancer-specific Warburg effect to regulate fast glucose intake consumption. Besides, PKM2 also contributes to cancer progression, especially tumor metastasis. In this study, we showed that PKM2 is upregulated in breast cancer tissues and the upregulating of PKM2 in breast cancer correlates with poor prognosis. PKM2 can regulate tumor progression by promoting tumor cell viability and mobility. Furthermore, overexpression of PKM2 can promote EMT to encourage tumor metastasis. These findings indicate PKM2 is a potentially useful diagnostic biomarker and therapeutic target in breast cancer.

Background: Ubiquitous mitochondrial creatine kinase (uMtCK) transfers high-energy phosphates from mitochondrially generated ATP to creatine to generate phosphocreatine. uMtCK overexpression has been reported in several malignant tumors, however, the clinical significance and impact of uMtCK in gastric cancer (GC) has not been comprehensively studied. Methods: We first examined uMtCK expression in GC by quantitative real-time PCR and western blot assays. Then the clinicopathological significance of aberrant uMtCK expression was determined by immunohistochemical staining in a GC tissue microarray. Kaplan–Meier analysis was used for survival analysis. The biological functions of uMtCK in GC cells were explored by wound-healing, transwell assays and glucose metabolism assays in vitro as well as a liver metastasis model by spleen injection in nude mice in vivo. Results: We verified that the expression of uMtCK was substantially elevated in GC tissues, significantly associating with a poorer prognosis in GC patients, especially for those with advanced stage. In univariate and multivariate analyses, uMtCK expression emerged as an independent prognostic factor for both disease-free survival and overall survival. Functionally, we demonstrated that uMtCK promoted glycolysis in GC cells and facilitated their migration, invasion and liver metastasis in vitro and in vivo. Mechanistically, uMtCK enhanced GC progression in a HK2-dependent glycolysis via acting the JNK-MAPK/JUN signaling pathway. Conclusions: uMtCK could serve as a novel independent prognostic biomarker as well as potential therapeutic target for GC patients, particularly for GC patients with an advanced UICC stage and tumor recurrence.

Background: Triple negative breast cancer (TNBC) is one of the most lethal breast cancer subtypes. Due to a lack of effective therapeutic targets, chemotherapy is still the main medical treatment for TNBC patients. Thus, it is important and necessary to find new therapeutic targets for TNBC. Recent genomic studies implicated the Hippo / Yap signal is over activated in TNBC, manifesting it plays a key role in TNBC carcinogenesis and cancer progression. RBCK1 was firstly identified as an important component for linear ubiquitin assembly complex (LUBAC) and facilitates NFKB signaling in immune response. Further studies showed RBCK1 also facilitated luminal type breast cancer growth and endocrine resistance via trans-activation estrogen receptor alpha. Methods: RBCK1 and YAP protein expression levels were measured by western blotting, while the mRNA levels of YAP target genes were measured by RT–PCR. RNA sequencing data were analyzed by Ingenuity Pathway Analysis. Identification of Hippo signaling activity was accomplished with luciferase assays, RT–PCR and western blotting. Protein stability assays and ubiquitin assays were used to detect YAP protein degradation. Ubiquitin-based immunoprecipitation assays were used to detect the specific ubiquitination modification on the YAP protein. Results: In our current study, our data revealed an opposite function for RBCK1 in TNBC progression. RBCK1 over-expression inhibited TNBC cell progression in vitro and in vivo, while RBCK1 depletion promoted TNBC cell invasion. The whole genomic expression profiling showed that RBCK1 depletion activated Hippo/YAP axis. RBCK1 depletion increased YAP protein level and Hippo target gene expression in TNBC. The molecular biology studies confirmed that RBCK1 could bind to YAP protein and enhance the stability of YAP protein by promoting YAP K48-linked poly-ubiquitination at several YAP lysine sites (K76, K204 and K321). Conclusion: Our study revealed the multi-faced RBCK1 function in different subtypes of breast cancer patients and a promising therapeutic target for TNBC treatment.

In this article, the scramble group of the invasion experiment in Fig. 2d, the Vector group of the migration experiment in Fig. 6c, the si-uMtCK + Lv-HK2 group of the invasion experiment in Fig. 6d and the experimental results of Lv-uMtCK + sh-HK2 in Fig. 6e were erroneously published; the Figs. 2 and 6 should have appeared as shown below.

This study aims to analyze the global cancer burden attributable to high fasting plasma glucose (HFPG), and to predict disease burden trends over the next