Senescent thyroid tumor cells promote their migration by inducing the polarization of M2-like macrophages.

PURPOSE: An in-depth understanding of the mechanism of thyroid cancer progression will help identify patients with thyroid cancer with a high risk of recurrence and metastasis. Although studies have pointed out that the senescence of thyroid tumor cells may stimulate TAMs and cause a series of changes. However, the role of TAMs in aging thyroid cancer cells is still unknown. The aim of this study was to investigate the function of TAMs in aging thyroid cancer cells. METHODS: We conducted in vitro model studies based on the K1 cell line to induce tumor cell senescence and study its effect on the differentiation of macrophages, flow cytometry was used to confirm polarization of macrophages, transwell assay was used to confirm changes of invasion and migration of tumor cells. RESULT: Our data indicate that aging thyroid tumor cell lines trigger the polarization of M2-like macrophages, accompanied by increased expression of CCL17, CCL18, IL-18, and TGFß1. This event is caused by the activation of the NFκB pathway upregulation of CXCL2 and CXCL3 is related. Further studies have shown that differentiated M2-like macrophages promote tumor cell migration (but have no effect on cell proliferation). CONCLUSION: Our study indicating that the interaction between tumor and TAMs also occurs in the advanced stages of thyroid tumors and will lead to faster tumors progress.

Effects of miR-27a upregulation on thyroid cancer cells migration, invasion, and angiogenesis.

Thyroid cancer is the most common type of endocrine tumor. MicroRNAs (miRNAs) play a critical role in a variety of diseases, especially cancer occurrence and progression. However, the specific mechanism by which miRNAs trigger disease states has not been fully elucidated. This study aims to investigate the role of miR-27a in thyroid cancer cells. A wound healing assay was adopted to examine cell migration. A transwell assay was applied to assess cell invasion. A thyroid cancer xenograft model was established using BALB/c nude mice. Western blot was performed to quantify iNOS expression. Tumor tissue blood vessel density was evaluated via immunohistochemistry assays. The results indicated that miR-27a downregulation inhibited thyroid cancer cell migration, while upregulation of miR-27a promoted thyroid cancer cell migration (P < 0.05). Furthermore, reduction in miR-27a expression suppressed thyroid cancer cell invasion (P < 0.05). In the nude mouse model of thyroid cancer xenograft, upregulation of miR-27 induced iNOS expression in pathological tumor tissues, whereas miR-27a inhibition resulted in the opposite effect (P < 0.05). CD105 level was also significantly increased during miR-27a upregulation, and was declined when miR-27a was inhibited (P < 0.05). In conclusion, miR-27a upregulation in thyroid cancer cells affects tumor cell migration, invasion, and angiogenesis by targeting downstream genes. Therefore, miR27a may act as a biomarker of thyroid cancer.

Association between five common polymorphisms in microRNA genes and the risk of gastric cancer: a meta-analysis.

Gastric cancer (GC) is a prevalent disease with a high mortality rate, especially in developing countries. Accumulating evidence suggests that single nucleotide polymorphisms in microRNA (miRNA) genes might influence the susceptibility to GC; such sequence variation might contribute to the development of disease by altering crucial cellular pathways. In this study, we assessed the correlation between the miR-146a G>C, miR-196a-2 C>T, miR-499 T>C, miRNA-27a A>G, and miRNA-149 T>C polymorphisms and the susceptibility to GC. A comprehensive literature search for relevant studies published prior to August 2014 was conducted using PubMed/Medline, Embase, Web of Science, the Cochrane Library, and CNKI databases along with Google Scholar. Meta-analysis was performed using odds ratios (ORs) and 95% confidence intervals (CIs) as effect measures, incorporating 19 studies encompassing 8285 patients and 10,716 controls. Allelic, dominant, recessive, homozygous, and heterozygous genetic models were examined. Pooled results showed that none of the five polymorphisms studied were statistically related to GC. Stratified analyses by ethnicity and source of controls were conducted for miR- 146a G>C and miR-196a-2 C>T. Subgroup analysis suggested that the miR-146a G allele might increase the risk of GC in hospital-based case-control (HCC) but not in population-based case-control studies (HCC: recessive model: OR = 1.23, 95%CI = 1.10-1.37, P < 0.001; heterozygous model: OR = 1.19, 95%CI = 1.06-1.34, P = 0.004). Overall, this meta-analysis failed to detect an association between five common miR-146a gene polymorphisms and GC susceptibility. However, this does not necessarily completely rule out a correlation between miRNA polymorphisms and GC susceptibility.

Detection of the genetic variation of polygalacturonase-inhibiting protein gene 2 in autotetraploid alfalfa (Medicago sativa) using an improved SSCP technique.

In this study, 2 approaches were adopted to obtain good single-strand conformation polymorphism (SSCP) data for autotetraploid alfalfa; primers were added to PCR products, and fluorescent-labeled primers were utilized. PCR-SSCP conditions for a 331-bp fragment in the coding region of polygalacturonase-inhibiting protein gene 2 in alfalfa (MsPGIP2) were optimized, and the results showed that the best SSCP gel pattern could be obtained when the loading mixture was made by mixing 1 µL PCR products, 0.2 to 0.8 µL unlabeled primers (50 µM) and 4 to 16 µL loading buffer. Furthermore, the use of the fluorescent-labeled primers resulted in 2 separated electrophoresis images from 2 complementary single DNA strands, thus making the determination of alleles and idiotypes a relatively easy task. In addition, the results of sequencing prove that the determination of alleles and idiotypes were accurate based on SSCP analysis. Finally, a total of 9 alleles with 18 SNP sites were identified for MsPGIP2 in the alfalfa variety 'Algonquin'. In conclusion, MsPGIP2 possessed great genetic variation, and the addition of primers to the PCR products in combination with the fluorescent labeling of primers could significantly improve the sensitivity and resolution of SSCP analysis. This technique could be used for genetic diversity detection and marker-assisted breeding of useful genes in autopolyploid species such as alfalfa.

Genome-wide multilocus analysis of intraspecific differentiation in Oryza rufipogon Griff. from China and the influence of introgression from O. sativa L.

Twenty-five populations of Oryza rufipogon from China and 144 cultivars of Oryza sativa were selected for this study. Based on the DNA fragment of Ehd1-4 and subspecies-specific sequence-tagged site markers in different chromosomes, intraspecific differentiation in O. rufipogon from China was analyzed. The introgression from O. sativa to O. rufipogon was also analyzed based on simple sequence repeat markers. The results revealed that the DNA fragment of Ehd1-4 could distinguish the O. sativa subspecies japonica and indica. Furthermore, although significant indica-japonica differentiation did not occur in most O. rufipogon populations from China, O. rufipogon varieties from Hainan Island and from the mainland of China showed differentiation tendencies. Japonica-like O. rufipogon varieties were predominant in Mainland China. However, more indica-like O. rufipogon varieties were found in Hainan Island. Finally, although cultivar-specific alleles were found in most of the O. rufipogon varieties from Hainan Island and Guangdong Province, some varieties remain pure and non-introgressive.

Variation of the OsGI intron and its phenotypic associations in Oryza rufipogon Griff. and Oryza sativa L.

We analyzed intron 9 of the OsGI gene in Oryza rufipogon and Oryza sativa in order to investigate evolutionary relationships in rice and the relationship between intron variation and phenotype. OsGI-9 was cloned in 38 O. rufipogon populations and in 139 O. sativa cultivars and the phylogeny was reconstructed. Seed cold tolerance and dormancy were quantified in O. sativa. Three OsGI-9 band types occurred in O. rufipogon: S-type (1.2 kb), F-type (0.9 kb), and FS-type (1.2 and 0.9 kb), whereas only the S-type and F-type occurred in O. sativa. The S-type contains two 255-bp repeats, the F-type contains one 255-bp repeat, and the FS-type contains both. All individuals could be divided into 5 groups in the organism's phylogenetic network: S-type O. rufipogon, F-type O. rufipogon, FS-type O. rufipogon, S-type O. sativa, and F-type O. sativa. F-type O. sativa are most closely related to F-type O. rufipogon and S-type O. sativa are most closely related to S-type O. rufipogon. Statistical analysis indicated that OsGI-9 type is significantly correlated with phenotype; most S-type O. sativa have strong seed dormancy and cold tolerance, and most F-type O. sativa have no seed dormancy and poor cold tolerance.

Association of AFLP and SCAR markers with common leafspot resistance in autotetraploid alfalfa (Medicago sativa).

To identify amplified fragment length polymorphism (AFLP) markers associated with resistance or susceptibility of alfalfa to common leafspot (CLS) caused by the fungus Pseudopeziza medicaginis (Dermateaceae), bulked segregant analysis was conducted based on an F(1(M × M)) population of 93 plants and a BC(1)S population of 91 plants. Three AFLP markers, ACTCAA(R206), TAGCAC(R185), and GGACTA(S264), were found to be associated with CLS resistance or susceptibility. All three markers were found at significantly different frequencies (71.9, 80.3 and 91.8%) compared to resistant or susceptible plants in the original population. Subsequently, these three AFLP markers were converted into three SCAR markers, ACTCAA(R136), TAGCAC(R128) and GGACTA(S254), which are easier to employ in breeding programs. The three SCAR markers were used in a randomly selected population with 50% resistance; the probability of finding one resistant plant was increased to 67.3, 66.7 and 90.0% with markers ACTCAA(R136), TAGCAC(R128) and GGACTA(S254), independently. If two of the SCAR markers were used simultaneously, the probability would be higher than 89%. The three SCAR markers identified in this study would be applicable for selection for CLS resistance in alfalfa breeding programs. Moreover, the genetic analysis indicated that CLS resistance in alfalfa is conferred by a single dominant gene.