Different anti-diabetic medications (ADMs) may modify cancer risk and mortality in patients with diabetes. We conducted a systematic review and meta-analysis to estimate the magnitude of association and quality of supporting evidence for each ADM. A total of 265 studies (44 cohort studies, 39 case-control studies, and 182 randomized controlled trials (RCT)) were identified, involving approximately 7.6 million and 137,540 patients with diabetes for observational studies and RCTs, respectively. The risk of bias overall was moderate. Meta-analysis demonstrated that the use of metformin or thiazolidinediones was associated with a lower risk of cancer incidence (RR = 0.86, 95% CI 0.83-0.90, I2 = 88.61%; RR = 0.93, 95% CI 0.91-0.96, I2 = 0.00% respectively). On the other hand, insulin, sulfonylureas and alpha glucosidase inhibitor use was associated with an increased risk of cancer incidence (RR = 1.21, 95% CI 1.08-1.36, I2 = 96.31%; RR = 1.20, 95% CI 1.13-1.27, I2 = 95.02%; RR = 1.10, 95% CI 1.05-1.15, I2 = 0.00% respectively). Use of other types of ADMs was not significantly associated with cancer risk. This study indicates that some ADMs may modify the risk of cancer in individuals with diabetes. Knowledge of this risk may affect the choice of ADM in individuals concerned about cancer or at increased risk for cancer.

Nut consumption may play a role in reducing cancer risk. Additional studies are needed to more accurately assess the relationship between nut consumption and the prevention of individual types of cancer, given the scarcity of available data.

Chromosome movements in mitosis are orchestrated by dynamic interactions between spindle microtubules and the kinetochore, a multiprotein complex assembled onto centromeric DNA of the chromosome. Here we show that phosphorylation of human HsMis13 by Aurora B kinase is required for functional kinetochore assembly in HeLa cells. Aurora B interacts with HsMis13 in vitro and in vivo. HsMis13 is a cognate substrate of Aurora B, and the phosphorylation sites were mapped to Ser-100 and Ser-109. Suppression of Aurora B kinase by either small interfering RNA or chemical inhibitors abrogates the localization of HsMis13 but not HsMis12 to the kinetochore. In addition, non-phosphorylatable but not wild type and phospho-mimicking HsMis13 failed to localize to the kinetochore, demonstrating the requirement of phosphorylation by Aurora B for the assembly of HsMis13 to kinetochore. In fact, localization of HsMis13 to the kinetochore is spatiotemporally regulated by Aurora B kinase, which is essential for recruiting outer kinetochore components such as Ndc80 components and CENP-E for functional kinetochore assembly. Importantly, phospho-mimicking mutant HsMis13 restores the assembly of CENP-E to the kinetochore, and tension developed across the sister kinetochores in Aurora B-inhibited cells. Thus, we reason that HsMis13 phosphorylation by Aurora B is required for organizing a stable bi-oriented microtubule kinetochore attachment that is essential for faithful chromosome segregation in mitosis.The kinetochore is a super-molecular complex assembled at each centromere in eukaryotes. It provides a chromosomal attachment point for the mitotic spindle, linking the chromosome to the microtubules and functions in initiating, controlling, and monitoring the movements of chromosomes during mitosis. The kinetochore of animal cells contains two functional domains; that is, the inner kinetochore, which is tightly and persistently associated with centromeric DNA sequences throughout the cell cycle and the outer kinetochore which is composed of many dynamic protein complexes that interact with microtubules only during mitosis. The stable propagation of eukaryotic cells requires each chromosome to be accurately duplicated and faithfully segregated. During mitosis, attaching, positioning, and bi-orientating kinetochores with the spindle microtubules play critical roles in chromosome segregation and genomic stability (see Refs. 1 and 2).Mitosis is orchestrated by signaling cascades that coordinate mitotic processes and ensure accurate chromosome segregation. The key switch for the onset of mitosis is the archetypal cyclin-dependent kinase Cdk1. In addition to the master mitotic kinase Cdk1, three other protein serine/threonine kinase families are also involved, including the Polo kinases, Aurora kinases, and the NEK 3 (NIMA-related kinases) (e.g. Refs. 3 and 4). Recent studies have demonstrated the involvement of NEK kinase in stabilization of the kinetochore-microtubule attachment (e.g. Ref. 5) and the critical role of Aurora B kinase in kineto...

The PML gene of acute promyelocytic leukemia (APL) encodes a cell-growth and tumor suppressor. PML localizes to discrete nuclear bodies (NBs) that are disrupted in APL cells, resulting from a reciprocal chromosome translocation t (15;17). Here we show that the nuclear localization of PML is also regulated by SUMO-3, one of the three recently identified SUMO isoforms in human cells. SUMO-3 bears similar subcellular distribution to those of SUMO-1 and -2 in the interphase nuclear body, which is colocalized with PML protein. However, both SUMO-2 and -3 are also localized to nucleoli, a region lacking SUMO-1. Immunoprecipitated PML protein bears SUMO-3 moiety in a covalently modified form, supporting the notion that PML is conjugated by SUMO-3. To determine the functional relevance of SUMO-3 conjugation on PML molecular dynamics, we suppressed SUMO-3 protein expression using a siRNA-mediated approach. Depletion of SUMO-3 markedly reduced the number of PML-containing NBa and their integrity, which is rescued by exogenous expression of SUMO-3 but not SUMO-1 or SUMO-2. The specific requirement of SUMO-3 for PML nuclear localization is validated by expression of SUMO-3 conjugation defective mutant. Moreover, we demonstrate that oligomerization of SUMO-3 is required for PML retention in the nucleus. Taken together, our studies provide first line of evidence showing that SUMO-3 is essential for PML localization and offer novel insight into the pathobiochemistry of APL.

During progression of hepatocellular carcinoma, multiple genetic and epigenetic alterations act to posttranslationally modulate the function of proteins that promote cancer invasion and metastasis. To define such abnormalities that contribute to liver cancer metastasis, we carried out a proteomic comparison of primary hepatocellular carcinoma and samples of intravascular thrombi from the same patient. Mass spectrometric analyses of the liver cancer samples revealed a series of acidic phospho-isotypes associated with the intravascular thrombi samples. In particular, we found that Thr567 hyperphosphorylation of the cytoskeletal protein ezrin was tightly correlated to an invasive phenotype of clinical hepatocellular carcinomas and to poor outcomes in tumor xenograft assays. Using phospho-mimicking mutants, we showed that ezrin phosphorylation at Thr567 promoted in vitro invasion by hepatocarcinoma cells. Phospho-mimicking mutant ezrinT567D, but not the nonphosphorylatable mutant ezrinT567A, stimulated formation of membrane ruffles, suggesting that Thr567 phosphorylation promotes cytoskeletal-membrane remodeling. Importantly, inhibition of Rho kinase, either by Y27632 or RNA interference, resulted in inhibition of Thr567 phosphorylation and a blockade to cell invasion, implicating Rho kinase-ezrin signaling in hepatocellular carcinoma cell invasion. Our findings suggest a strategy to reduce liver tumor metastasis by blocking Rho kinase-mediated phosphorylation of ezrin.

The association between parity and endometrial cancer risk is inconsistent from observational studies. We aimed to quantitatively assess the relationship by summarizing all relevant epidemiological studies. PubMed (MEDLINE), Embase and Scopus were searched up to February 2015 for eligible case–control studies and prospective studies. Random-effects model was used to pool risk estimations. Ten prospective studies, 35 case-control studies and 1 pooled analysis of 10 cohort and 14 case-control studies including 69681 patients were identified. Pooled analysis revealed that there was a significant inverse association between parity and risk of endometrial cancer (relative risk (RR) for parous versus nulliparous: 0.69, 95% confidence interval (CI) 0.65–0.74; I2 = 76.9%). By evaluating the number of parity, we identified that parity number of 1, 2 or 3 versus nulliparous demonstrated significant negative association (RR = 0.73, 95% CI 0.64–0.84, I2 = 88.3%; RR = 0.62, 95% CI 0.53–0.74, I2 = 92.1%; and RR = 0.68, 95% CI 0.65–0.70, I2 = 20.0% respectively). The dose-response analysis suggested a nonlinear relationship between the number of parity and endometrial cancer risk. The RR decreased when the number of parity increased. This meta-analysis suggests that parity may be associated with a decreased risk of endometrial cancer. Further studies are warranted to replicate our findings.

Carboxyl/cholinesterase (CCE) is a large gene family of diverse functions, but in insects its function with respect to catabolism of sex pheromone components and plant volatiles is not well understood. In the present study, we cloned and functionally characterized one putative odorant-degrading enzyme (ODE) of the CCE family, SexiCXE14, from Spodoptera exigua. The tissue-temporal expression pattern revealed that the mRNA level of SexiCXE14 is antennae-enriched, sex equivalent and peaks at 3 days after moth eclosion. Functional study using the recombinant enzyme determined that SexiCXE14 has high degrading activity (Vmax) to host plant volatiles, suggesting its role in degradation of these volatiles. In addition, SexiCXE14 may also play a role in the degradation of sex pheromone components, as the Vmax and affinity parameter (Km) values with the sex pheromones are similar to those of reported pheromone degrading enzymes (PDEs). Further analysis of the relationship between substrate structure and enzymatic activity demonstrated that carbon chain length is a major influential factor, while the number of double bonds also affects the enzymatic activity. In addition, SexiCXE14 displays lower activity at acidic pH levels (pH 5.0) than in neutral conditions (pH 6.5). By characterizing this new ODE the present study provides insights in understanding of the high sensitivity of the moth olfactory system.

Loss or gain of whole chromosome, the form of chromosome instability commonly associated with cancers is thought to arise from aberrant chromosome segregation during cell division. Chromosome segregation in mitosis is orchestrated by the interaction of kinetochores with spindle microtubules. Our studies show that NEK2A is a kinetochore-associated protein kinase essential for faithful chromosome segregation. However, it was unclear how NEK2A ensures accurate chromosome segregation in mitosis. Here we show that NEK2A-mediated Hec1 (highly expressed in cancer) phosphorylation is essential for faithful kinetochore microtubule attachments in mitosis. Using phospho-specific antibody, our studies show that NEK2A phosphorylates Hec1 at Ser165 during mitosis. Although such phosphorylation is not required for assembly of Hec1 to the kinetochore, expression of non-phosphorylatable mutant Hec1 S165 perturbed chromosome congression and resulted in a dramatic increase in microtubule attachment errors, including syntelic and monotelic attachments. Our in vitro reconstitution experiment demonstrated that Hec1 binds to microtubule in low affinity and phosphorylation by NEK2A, which prevents aberrant kinetochore-microtubule connections in vivo, increases the affinity of the Ndc80 complex for microtubules in vitro. Thus, our studies illustrate a novel regulatory mechanism in which NEK2A kinase operates a faithful chromosome attachment to spindle microtubule, which prevents chromosome instability during cell division.