Natural variation in the promoter of rice calcineurin B-like protein10 (OsCBL10) affects flooding tolerance during seed germination among rice subspecies.

Rice (Oryza sativa L.) has two ecotypes, upland and lowland rice, that have been observed to show different tolerance levels under flooding stress. In this study, two rice cultivars, upland (Up221, flooding-intolerant) and lowland (Low88, flooding-tolerant), were initially used to study their molecular mechanisms in response to flooding germination. We observed that variations in the OsCBL10 promoter sequences in these two cultivars might contribute to this divergence in flooding tolerance. Further analysis using another eight rice cultivars revealed that the OsCBL10 promoter could be classified as either a flooding-tolerant type (T-type) or a flooding-intolerant type (I-type). The OsCBL10 T-type promoter only existed in japonica lowland cultivars, whereas the OsCBL10 I-type promoter existed in japonica upland, indica upland and indica lowland cultivars. Flooding-tolerant rice cultivars containing the OsCBL10 T-type promoter have shown lower Ca2+ flow and higher α-amylase activities in comparison to those in flooding-intolerant cultivars. Furthermore, the OsCBL10 overexpression lines were sensitive to both flooding and hypoxic treatments during rice germination with enhanced Ca2+ flow in comparison to wild-type. Subsequent findings also indicate that OsCBL10 may affect OsCIPK15 protein abundance and its downstream pathways. In summary, our results suggest that the adaptation to flooding stress during rice germination is associated with two different OsCBL10 promoters, which in turn affect OsCBL10 expression in different cultivars and negatively affect OsCIPK15 protein accumulation and its downstream cascade.

RANK rs1805034 T>C Polymorphism Is Associated with Susceptibility to Gastric Cardia Adenocarcinoma in a Chinese Population.

BACKGROUND: Gastric cardia adenocarcinoma (GCA) is a common malignant tumor of the digestive tract with a high incidence in China. Genetic factors such as single nucleotide polymorphisms (SNPs) may contribute to the carcinogenesis of GCA. METHODS: We conducted a hospital-based case-control study to evaluate the genetic association of functional SNPs with susceptibility to GCA development. A total of 330 GCA cases and 608 controls were recruited for this study. The SNPs OPG rs3102735 T>C and rs2073618 G>C, RANK rs1805034 T>C, and RANKL rs9533156 T>C and rs2277438 A>G were determined using the ligation detection reaction method. RESULTS: Our findings suggest that RANK rs1805034 T>C is associated with susceptibility to GCA, which is more evident among male patients, elderly patients (≥ 60 years), smokers, and patients who do not consume alcohol. CONCLUSION: Based on our findings, the functional SNP RANK rs1805034 T>C may be an indicator for individual susceptibility to GCA. However, further larger studies with other ethnic populations and tissue-specific biological characterization are required to confirm the current findings.

B-cell Lymphoma 2 rs17757541 C>G polymorphism was associated with an increased risk of gastric cardiac adenocarcinoma in a Chinese population.

AIM: Apoptosis has been considered as a fundamental component in cancer pathogenesis, and related genetic factors might play an important role in gastric cardiac adenocarcinoma (GCA) genesis. METHODS: We conducted a hospital based case-control study to evaluate the genetic effects of functional single nucleotide polymorphisms (SNPs): BCL2 rs17757541 C>G, BCL2 rs12454712 T>C, FAS rs2234767 G>A, FASL/FASLG rs763110 C>T, ERBB2 rs1136201 A>G and VEGFR2/KDR rs11941492 C>T on the development of GCA. A total of 243 GCA cases and 476 controls were recruited for the study and genotypes were determined using a custom-by-design 48-Plex SNPscanTM Kit. RESULTS: The BCL2 rs17757541 C>G polymorphism was associated with increased risk of GCA. However, there was no significant associations with the other five SNPs. Stratified analyses indicated a significantly increased risk of GCA associated with the BCL2 rs17757541 C>G polymorphism among males, older patients and those with a history of smoking or drinking. CONCLUSION: These findings indicated that the functional polymorphism BCL2 rs17757541 C>G might contribute to GCA susceptibility. However, our results were limited by small sample size. Future larger studies are required to confirm our current findings.

Interleukin 10 rs1800872 T>G polymorphism was associated with an increased risk of esophageal cancer in a Chinese population.

AIM: Esophageal cancer is the eighth most common cancer and sixth leading cause of cancer associated death worldwide. The 5 year survival rate for esophageal cancer patients is very poor and accounts for only 12.3%. Besides environmental risk factors, genetic factors might play an important role in the esophageal cancer carcinogenesis. METHODS: We conducted a hospital based case-control study to evaluate the genetic effects of functional single nucleotide polymorphisms (SNPs): interleukin 9 (IL9) rs31563 C>T, IL9 rs31564 G>T, IL10 rs1800872 T>G, IL12A rs2243115 T>G, IL12B rs3212227 T>G and IL13 rs1800925 C>T on the development of esophageal cancer. A total of 380 esophageal squamous cell carcinoma (ESCC) cases and 380 controls were recruited for this study. The genotypes were determined using a custom-by-design 48-Plex SNPscanTM Kit. RESULTS: The IL10 rs1800872 T>G polymorphism was associated with an increased risk of ESCC. However, there were no significant links with the other five SNPs. Stratified analyses indicated no significant risk of ESCC associated with the IL10 rs1800872 T>G polymorphism evident among any subgroups. CONCLUSION: These findings indicated that functional polymorphism IL10 rs1800872 T>G might contribute to ESCC susceptibility. However, our results were obtained with a limited sample size, so that the power of our analysis was low. Future larger studies with more rigorous study designs of other ethnic populations are required to confirm the current findings.

SRC kinase family inhibitor PP2 promotes DMSO-induced cardiac differentiation of P19 cells and inhibits proliferation.

BACKGROUND: It has been reported recently that PP2, a Src family kinase inhibitor, promotes selective cardiogenesis in embryonic stem cells. However, there is no other research proved pro-cardiogenic characteristic of PP2 so far. In this study, we explored the potential cardiogenic effect of PP2 on P19 cells differentiation. METHODS: P19-αMHC-EGFP cell line was established by transfecting P19 cells with αMHC-EGFP vector in order to evaluate cardiogenesis with EGFP. P19-αMHC-EGFP cells and P19 cells were induced to differentiate into cardiomyocytes with 1%DMSO, 5 µmol/L PP2, or both 1%DMSO and 5 µmol/L PP2. Differentiated cells from P19-αMHC-EGFP cells were then assessed under confocal microscope. Western-blot and RT-PCR were also performed to detect expression of cardiac troponin I and cardiac transcription factors respectively. In addition, the effects of PP2 on proliferation of P19 cells were further examined using Cell Counting Kit-8. RESULTS: EGFP positive cells were firstly detected on day 7 and PP2 alone cannot induce efficient cardiac differentiation of P19-αMHC-EGFP cells. However PP2 supplementation dramatically increases DMSO induced cardiac differentiation than DMSO alone. It was also found that PP2 inhibit proliferation of P19 cells in both a dose-dependent manner and a time-dependent manner. CONCLUSION: PP2 alone cannot substitute DMSO to induce cardiac differentiation, however, PP2 supplementation drastically promotes DMSO-induced cardiac differentiation of P19 cells. The increased percentages of differentiated cardiac myocytes is partly resulting from cell proliferative inhibit effect of PP2 in undifferentiated P19 cells. P19-αMHC-EGFP cell line has the potential to be used for regenerative therapies in experimental models of heart repair.

Expressing murine p56Hck(ca) promotes HeLa cells' motility and invasion via triggering redistribution of F-actin and microtubules.

Hck is the unique example among the Src PTKs to be expressed as two isoforms, which are generated by alternative translation. The two isoforms differs from each other by a 21 N-terminal amino acids sequence which supports myristoylation. Though it has been shown that these different acylation states govern the different subcellular localization of the isoforms and each Hck isoform could play a specific role, little study focus on the function of p56Hck. To investigated the role of p56Hck isoform in cell migration, GFP targeted p56Hck plasmid and its constitutively active form were constructed and transiently transfected into HeLa cells, F-actin staining and Indirect immunofluorescence for microtubules were then performed. Phagokinetic track motility assay and In vitro invasion assays were also investigated after transiently transfection respectively. In this study, we found ectopically expressing a constitutively active form of 56Hck will lead to membrane protrusion and F-actin reorganization in HeLa cells. Both 56Hck and its constitutive active form will lead to redistribution of microtubules and enhancement of cell motility and cell invasion. Hck inhibitor PP2 supplementation eliminated cell motility and cell invasion of p56Hck while PP3, a negative control of PP2 didn't eliminate cell motility and cell invasion of p56Hck. It is indicated that enhanced cell motility and cell invasion in p56Hck ectopically expressed HeLa cells are the results of reorganization of F-actin and microtubules.

Effects of low-level laser irradiation on mesenchymal stem cell proliferation: a microarray analysis.

Increased proliferation after low-level laser irradiation (LLLI) has been well demonstrated in many cell types including mesenchymal stem cells (MSCs), but the exact molecular mechanisms involved remain poorly understood. The aim of this study was to investigate the change in mRNA expression in rat MSCs after LLLI and to reveal the associated molecular mechanisms. MSCs were exposed to a diode laser (635 nm) as the irradiated group. Cells undergoing the same procedure without LLLI served as the control group. Proliferation was evaluated using the MTS assay. Differences in the gene expression profiles between irradiated and control MSCs at 4 days after LLLI were analyzed using a cDNA microarray. Gene ontology and pathway analysis were used to find the key regulating genes followed by real-time PCR to validate seven representative genes from the microarray assays. This procedure identified 119 differentially expressed genes. Real-time PCR confirmed that the expression levels of v-akt murine thymoma viral oncogene homolog 1 (Akt1), the cyclin D1 gene (Ccnd1) and the phosphatidylinositol 3-kinase, catalytic alpha polypeptide gene (Pik3ca) were upregulated after LLLI, whereas those of protein tyrosine phosphatase non-receptor type 6 (Ptpn6) and serine/threonine kinase 17b (Stk17b) were downregulated. cDNA microarray analysis revealed that after LLLI the expression levels of various genes involved in cell proliferation, apoptosis and the cell cycle were affected. Five genes, including Akt1, Ptpn6, Stk17b, Ccnd1 and Pik3ca, were confirmed and the PI3K/Akt/mTOR/eIF4E pathway was identified as possibly playing an important role in mediating the effects of LLLI on the proliferation of MSCs.