Decreased miR-452 expression in human colorectal cancer and its tumor suppressive function.

MicroRNA-452 (miR-452) is dysregulated in some human malignancies, and is correlated with tumor progression. However, its expression and function in human colorectal cancer (CRC) remain unclear. The aim of our study was to explore the effects of miR-452 in CRC tumorigenesis and development. Using reverse transcription quantitative real-time polymerase chain reaction, we detected miR-452 expression in CRC cell lines and primary tumor tissues. We also examined the association between miR-452 expression and clinicopathological factors. We then investigated the effects of miR-452 on the biological behavior of CRC cells. miR-452 expression was significantly downregulated in CRC compared with the adjacent noncancerous tissues. A low level of miR-452 was associated with larger tumor size, deeper invasion depth, and advanced TNM stage. Multivariate Cox regression analysis identified decreased miR-452 expression as an independent factor predicting poor prognosis for CRC patients. In addition, in vitro functional analysis showed that overexpression of miR-452 in HCT116 cells reduced cell proliferation, promoted cell apoptosis, and inhibited cell invasion and migration. These findings indicate that miR-452acts as a tumor suppressor in CRC, and would serve as a novel molecular therapeutic agent for the treatment of the disease.

IL-8 -251T/A polymorphism is associated with susceptibility to acute pancreatitis.

We conducted a case-control study to clarify the asso-ciations between inflammatory cytokine, including interleukin (IL)-1b, IL-6, IL-8, and IL-10, polymorphisms and risk of acute pancreatitis. Genotyping analyses of IL-1ß+3954 C/T (rs1143634), IL-1ß-511 C/T (rs16944), IL-6 -174 G/C (rs1800795), IL-6 -634 C/G (rs1800796), IL-8 -251T/A (rs4073), IL-10 -1082A/G (rs1800896), and IL-10 -819C/T (rs1800871) were conducted using polymerase chain reaction-restriction fragment length of polymorphism. Unconditional logistic regression analysis was utilized to assess the potential association be-tween genotype frequencies and risk of acute pancreatitis. Multivari-ate regression analyses showed that subjects carrying the IL-8 -251 AA genotype had a significantly increased risk of acute pancreatitis, with an adjusted odds ratio (95% confidence interval) of 1.55 (1.02-2.36). However, we found no significant association between IL-1ß +3954 C/T, IL-1ß -511 C/T, IL-6 -174 G/C, IL-6 -174 G/C, IL-6 -634 C/G, IL-10 -1082A/G, or IL-10 -819C/T polymorphisms and risk of acute pancreatitis. We found that the IL-8 -251T/A polymorphism was associated with a higher susceptibility to acute pancreatitis in a Chinese population.

Efficient identification of ornamental peach cultivars using RAPD markers with a manual cultivar identification diagram strategy.

One of the most important uses of DNA markers is cultivar identification. However, no DNA fingerprint analysis strategy is available for making DNA markers helpful in practical plant cultivar identification, especially for the identification of a large number of cultivars. We developed a manual cultivar identification diagram strategy for efficient identification of plant cultivars, from which a cultivar identification diagram (CID) of genotyped plant individuals can be constructed manually. This CID could be used as a reference for quick identification of plant cultivars of interest. We used 11-mer RAPD primers to amplify DNA samples of 32 ornamental peach genotypes; all the cultivars were well distinguished by fingerprints from 6 primers. The utility of this CID was verified by identification of three randomly chosen groups of cultivars among the 32 ones that we selected. This CID generated will be useful for the identification of commercially important ornamental peach cultivars.

Assessing genetic divergence in interspecific hybrids of Aechmea gomosepala and A. recurvata var. recurvata using inflorescence characteristics and sequence-related amplified polymorphism markers.

Conventional hybridization and selection techniques have aided the development of new ornamental crop cultivars. However, little information is available on the genetic divergence of bromeliad hybrids. In the present study, we investigated the genetic variability in interspecific hybrids of Aechmea gomosepala and A. recurvata var. recurvata using inflorescence characteristics and sequence-related amplified polymorphism (SRAP) markers. The morphological analysis showed that the putative hybrids were intermediate between both parental species with respect to inflorescence characteristics. The 16 SRAP primer combinations yield 265 bands, among which 154 (57.72%) were polymorphic. The genetic similarity was an average of 0.59 and ranged from 0.21 to 0.87, indicating moderate genetic divergence among the hybrids. The unweighted pair group method with arithmetic average (UPGMA)-based cluster analysis distinguished the hybrids from their parents with a genetic distance coefficient of 0.54. The cophenetic correlation was 0.93, indicating a good fit between the dendrogram and the original distance matrix. The two-dimensional plot from the principal coordinate analysis showed that the hybrids were intermediately dispersed between both parents, corresponding to the results of the UPGMA cluster and the morphological analysis. These results suggest that SRAP markers could help to identify breeders, characterize F(1) hybrids of bromeliads at an early stage, and expedite genetic improvement of bromeliad cultivars.

An improved strategy based on RAPD markers efficiently identified 95 peach cultivars.

DNA markers have useful applications in cultivar identification. A novel analysis approach called cultivar identification diagram (CID) was developed using DNA markers in the separation of plant individuals. This new strategy is less time- and cost-consuming, has reliable results, and was constructed for fingerprinting. Ten 11-mer primers were used to amplify the genotypes; all 95 peach genotypes (from the National Peach Germplasm Repository, in Nanjing, China) were distinguished by a combination of 54 primers. The utilization of the CID among these 95 peach cultivars was also verified by the identification of three randomly chosen groups of cultivars. This identification showed some advantages including the use of fewer primers and easy separation of all cultivars by the corresponding primers marked in the right position on the CID. This peach CID could provide the information to separate any peach cultivars of these 95, which may be of help to the peach industry in China and for the utilization of DNA markers to identify other plant species.