Characterization and transformation of TtMYB1 transcription factor from Tritipyrum to improve salt tolerance in wheat.

BACKGROUND: Common wheat (Triticum aestivum L.) is a worldwide cereal crop, which is an integral part of the diets of many countries. In addition, the MYB gene of wheat plays a role in the response to salt stress. RESULTS: "Y1805" is a Tritipyrum variety that is relatively tolerant to salt. We used transcriptome analysis to show that the "Y1805" MYB gene was both highly expressed and sensitive to salt stress. Compared with control roots, the level of MYB expression during salt stress was higher, which rapidly decreased to control levels during the recovery process. MYB gene relative expression showed the highest levels in "Y1805" roots during salt stress, with the stems and then leaves being the next highest stressed tissues. The novel MYB gene (TtMYB1) was successfully cloned from "Y1805". It showed a coding sequence length of 783 bp with 95.79% homology with Tel2E01G633100 from Thinopyrum elongatum. TtMYB1 and MYB from Th. elongatum were clustered in the same branch using phylogenetic analysis, which indicated high similarities. The TtMYB1 gene is located in the nucleus. The coleoptile method was employed when a TtMYB1 overexpression vector was used during transformation into "1718" (common wheat). Under high salt stress, TtMYB1 leaves of overexpression lines had decreased wilting, when compared with wild-type (WT) plants. During normal conditions, salt stress, and recovery, the lengths of the roots and the heights of seedlings from the overexpression lines were found to be significantly greater than roots and seedlings of WT plants. In addition, during high salt stress, the overexpression lines showed that proline and soluble sugar levels were higher than that of WT plants, but with lower malondialdehyde levels. Forty-three proteins that interacted with TtMYB1 were identified using the yeast two-hybrid assay. Protein-protein interaction analyses indicated that most were SANT domain-containing and Wd repeat region domain-containing proteins. Among these proteins, ribosomal proteins were the main node. Abiotic stress-related terms (such as "carbonate dehydratase activity", "protein targeting peroxisomes", and "glutathione peroxidase activity") were enriched in GO analysis. In KEGG analysis, "carbohydrate metabolism", "environmental information processing", "genetic information processing", "signaling and cell precursors", and "energy metabolism" pathways were enriched. CONCLUSION: The TtMYB1 gene might enhance salt tolerance by increasing proline and soluble sugar content and antioxidase activity in transgenic wheat. It therefore has the potential to enhance high salt tolerance in plants.

Nomogram for predicting the preoperative lymph node metastasis in resectable pancreatic cancer.

BACKGROUND: Lymph node metastasis (LNM) is a critical prognostic factor in resectable pancreatic cancer (PC) patients, determining treatment strategies. This study aimed to develop a clinical model to adequately and accurately predict the risk of LNM in PC patients. METHODS: 13,200 resectable PC patients were enrolled from the SEER (Surveillance, Epidemiology, and End Results) database, and randomly divided into a training group and an internal validation group at a ratio of 7:3. An independent group (n = 62) obtained from The First Affiliated Hospital of Xinxiang Medical University was enrolled as the external validation group. The univariate and multivariate logistic regression analyses were used to screen independent risk factors for LNM. The minimum Akaike's information criterion (AIC) was performed to select the optimal model parameters and construct a nomogram for assessing the risk of LNM. The performance of the nomogram was assessed by the receiver operating characteristics (ROC) curve, calibration plot, and decision curve analysis (DCA). In addition, an online web calculator was designed to assess the risk of LNM. RESULT: A total of six risk predictors (including age at diagnosis, race, primary site, grade, histology, and T-stage) were identified and included in the nomogram. The areas under the curves (AUCs) [95% confidential interval (CI)] were 0.711 (95%CI: 0.700-0.722), 0.700 (95%CI: 0.683-0.717), and 0.845 (95%CI: 0.749-0.942) in the training, internal validation and external validation groups, respectively. The calibration curves showed satisfied consistency between nomogram-predicted LNM and actual observed LNM. The concordance indexes (C-indexes) in the training, internal, and external validation sets were 0.689, 0.686, and 0.752, respectively. The DCA curves of the nomogram demonstrated good clinical utility. CONCLUSION: We constructed a nomogram model for predicting LNM in pancreatic cancer patients, which may help oncologists and surgeons to choose more individualized clinical treatment strategies and make better clinical decisions.

Characterization of a Novel TtLEA2 Gene From Tritipyrum and Its Transformation in Wheat to Enhance Salt Tolerance.

Late embryogenesis-abundant (LEA) proteins are critical in helping plants cope with salt stress. "Y1805" is a salt-tolerant Tritipyrum. We identified a "Y1805"-specific LEA gene that was expressed highly and sensitively under salt stress using transcriptome analysis. The novel group 2 LEA gene (TtLEA2-1) was cloned from "Y1805." TtLEA2-1 contained a 453 bp open reading frame encoding an 151-amino-acid protein that showed maximum sequence identity (77.00%) with Thinopyrum elongatum by phylogenetic analysis. It was mainly found to be expressed highly in the roots by qRT-PCR analysis and was located in the whole cell. Forty-eight candidate proteins believed to interact with TtLEA2-1 were confirmed by yeast two-hybrid analysis. These interacting proteins were mainly enriched in "environmental information processing," "glycan biosynthesis and metabolism," and "carbohydrate metabolism." Protein-protein interaction analysis indicated that the translation-related 40S ribosomal protein SA was the central node. An efficient wheat transformation system has been established. A coleoptile length of 2 cm, an Agrobacteria cell density of 0.55-0.60 OD600, and 15 KPa vacuum pressure were ideal for common wheat transformation, with an efficiency of up to 43.15%. Overexpression of TaLEA2-1 in wheat "1718" led to greater height, stronger roots, and higher catalase activity than in wild type seedlings. TaLEA2-1 conferred enhanced salt tolerance in transgenic wheat and may be a valuable gene for genetic modification in crops.

Comparative Analysis of Physiological, Enzymatic, and Transcriptomic Responses Revealed Mechanisms of Salt Tolerance and Recovery in Tritipyrum.

Salt stress results in the severe decline of yield and quality in wheat. In the present study, salt-tolerant Tritipyrum ("Y1805") and salt-sensitive wheat "Chinese Spring" ("CS") were selected from 121 wheat germplasms to test their physiological, antioxidant enzyme, and transcriptomic responses and mechanisms against salt stress and recovery. 56 chromosomes were identified in "Y1805" that comprised A, B, and D chromosomes from wheat parent and E chromosomes from Thinopyrum elongatum, adding to salt-tolerant trait. Salt stress had a greater inhibitory effect on roots than on shoots, and "Y1805" demonstrated stronger salt tolerance than "CS." Compared with "CS," the activities of superoxide dismutase and catalase in "Y1805" significantly increased under salt stress. "Y1805" could synthesize more proline and soluble sugars than "CS." Both the net photosynthetic rate and chlorophyll a/b were affected by salt stress, though the level of damage in "Y1805" was significantly less than in "CS." Transcriptome analysis showed that the differences in the transcriptional regulatory networks of "Y1805" were not only in response to salt stress but also in recovery. The functions of many salt-responsive differentially expressed genes were correlated closely with the pathways "peroxisome," "arginine and proline metabolism," "starch and sucrose metabolism," "chlorophyll and porphyrin metabolism," and "photosynthesis."

Integrated transcriptomic and proteomic analysis of Tritipyrum provides insights into the molecular basis of salt tolerance.

BACKGROUND: Soil salinity is a major environmental stress that restricts crop growth and yield. METHODS: Here, crucial proteins and biological pathways were investigated under salt-stress and recovery conditions in Tritipyrum 'Y1805' using the data-independent acquisition proteomics techniques to explore its salt-tolerance mechanism. RESULTS: In total, 44 and 102 differentially expressed proteins (DEPs) were identified in 'Y1805' under salt-stress and recovery conditions, respectively. A proteome-transcriptome-associated analysis revealed that the expression patterns of 13 and 25 DEPs were the same under salt-stress and recovery conditions, respectively. 'Response to stimulus', 'antioxidant activity', 'carbohydrate metabolism', 'amino acid metabolism', 'signal transduction', 'transport and catabolism' and 'biosynthesis of other secondary metabolites' were present under both conditions in 'Y1805'. In addition, 'energy metabolism' and 'lipid metabolism' were recovery-specific pathways, while 'antioxidant activity', and 'molecular function regulator' under salt-stress conditions, and 'virion' and 'virion part' during recovery, were 'Y1805'-specific compared with the salt-sensitive wheat 'Chinese Spring'. 'Y1805' contained eight specific DEPs related to salt-stress responses. The strong salt tolerance of 'Y1805' could be attributed to the strengthened cell walls, reactive oxygen species scavenging, osmoregulation, phytohormone regulation, transient growth arrest, enhanced respiration, transcriptional regulation and error information processing. These data will facilitate an understanding of the molecular mechanisms of salt tolerance and aid in the breeding of salt-tolerant wheat.

Degradation of Mcl-1 through GSK-3ß Activation Regulates Apoptosis Induced by Bufalin in Non-Small Cell Lung Cancer H1975 Cells.

BACKGROUND/AIMS: Mcl-1, an anti-apoptotic Bcl-2 family member, is often overexpressed in non-small cell lung cancer (NSCLC). Bufalin has been reported to induce apoptosis in various tumor cells. However, there is no report showing that bufalin could downregulate Mcl-1 expression in NSCLC. METHODS: Cell proliferation was analyzed by cell counting kit-8 (CCK-8) assay in H1975 cells. Cell apoptosis was detected by flow cytometry. Mcl-1 mRNA was detected by RT-PCR. The expression of apoptosis-associated proteins in H1975 cells was detected by western blotting. The levels of Mcl-1 ubiquitination and NOXA were analyzed by Immunoprecipitation assay. RESULTS: Cell growth was inhibited by bufalin in a time and dose-dependent manner. Bufalin induced apoptosis in NSCLC cells by activating caspase cascades and downregulating Mcl-1 expression. However, overexpression of Mcl-1 diminished bufalin-induced apoptosis. Furthermore, bufalin did not reduce Mcl-1 mRNA expression in H1975 cells, but strongly promoted Mcl-1 protein degradation. Proteasome inhibitor MG132 markedly prevented the degradation of Mcl-1 and blocked bufalin-induced Mcl-1 reduction. Bufalin did not significantly affect NOXA protein levels, but downregulated the expression of p-GSK-3ß. GSK-3 inhibitor and GSK-3ß siRNA resulted in increased levels of Mcl-1 and reversed the bufalin-induced Mcl-1 degradation. CONCLUSION: Bufalin induced cell apoptosis in H1975 cells may be through downregulation of Mcl-1. Proteasomal degradation of Mcl-1 via GSK-3ß activation was involved in bufalin-induced apoptosis.

[Bufalin reverses hepatocyte growth factor-induced resistance to afatinib in H1975 lung cancer cells].

OBJECTIVE: To investigate the effects of bufalin in reversing hepatocyte growth factor (HGF)-induced resistance to afatinib in H1975 lung cancer cells, and explore its possible mechanism. METHODS: The afatinib-resistant H1975 lung cancer cells (H1975AR) were induced by exogenous HGF and transfected with recombinant adenoviral vector Ad-HGF-GFP. The cytostatic effects of bufalin, afatinib and bufalin plus afatinib on H1975AR cells were evaluated by MTT assay. The impact of combined therapy with bufalin and afatinib on invasion of H1975AR cells was determined by transwell migration assay. The concentrations of HGF in the culture supernatants of H1975/Vec and H1975/HGF cells were determined by ELISA. The expression of EGFR, cMET and EMT signal pathway-related proteins in H1975AR cells treated with bufalin, afatinib and bufalin plus afatinib were detected by Western blot. RESULTS: The results of MTT assay showed that afatinib did not inhibit the growth of H1975 cells, but after 72 h of the combined treatment with bufalin and afatinib and in the presence of HGF, the growth rate of H1975 cells was (38.67 ± 8.76)%, significantly lower than the growth rate of (63.45 ± 12.65)% in the H1975 cells treated with HGF alone (P < 0.05). The results of transwell migration assay showed that in the presence of HGF, afatinib plus bufalin combination therapy markedly decreased the number of invaded H1975 cells through the Matrigel chamber (48.98 ± 11.43), significantly lower than the 118.92 ± 37.29 of afatinib-treated or the 88.84 ± 19.53 of bufalin-treated cells (P < 0.05 for all). The result of ELISA showed that H1975/HGF cells secreted high levels of HGF, and afatinib and bufalin had no effect on the HGF secretion in H1975/HGF cells. The results of Western blot analysis showed that the expression of p-EGFR, p-cMet, p-AKT, p-ERK, vimentin and snail in H1975AR cells treated with bufalin puls afatinb was down-regulated markedly, and the expression of E-cadherin was up-regulated markedly. CONCLUSIONS: Combination of bufalin and afatinib strongly inhibits the growth of H1975AR lung cancer cells and decreases their invasion ability. The possible mechanism of combined treatment with bufalin and afatinib may be related to the blocking of cMet/PI3K/AKT and cMet/MAPK/ERK pathways and inhibiting of epithelial-mesenchymal transition.

Chromosomal Behavior during Meiosis in the Progeny of Triticum timopheevii × Hexaploid Wild Oat.

The meiotic behavior of pollen mother cells (PMCs) of the F2 and F3 progeny from Triticum timopheevii × hexaploid wild oat was investigated by cytological analysis and sequential C-banding-genomic in situ hybridization (GISH) in the present study. A cytological analysis showed that the chromosome numbers of the F2 and F3 progeny ranged from 28 to 41. A large number of univalents, lagging chromosomes, chromosome bridges and micronuclei were found at the metaphase I, anaphase I, anaphase II and tetrad stages in the F2 and F3 progeny. The averages of univalents were 3.50 and 2.73 per cell, and those of lagging chromosomes were 3.37 and 1.87 in the F2 and F3 progeny, respectively. The PMC meiotic indices of the F2 and F3 progeny were 12.22 and 20.34, respectively, indicating considerable genetic instability. A sequential C-banding-GISH analysis revealed that some chromosomes and fragments from the hexaploid wild oat were detected at metaphase I and anaphase I in the progeny, showing that the progeny were of true intergeneric hybrid origin. The alien chromosomes 6A, 7A, 3C and 2D were lost during transmission from F2 to F3. In addition, partial T. timopheevii chromosomes appeared in the form of univalents or lagging chromosomes, which might result from large genome differences between the parents, and the wild oat chromosome introgression interfered with the wheat homologues' normally pairing.

Effects of silencing the ATP-binding cassette protein E1 gene by electroporation on the proliferation and migration of EC109 human esophageal cancer cells.

In the present study, the gene expression of ATP-binding cassette protein E1 (ABCE1) in the EC109 human esophageal cancer cell line was silenced using electroporation to examine the effect if the ABCE1 gene on the growth migration and cell cycle of cancer cells. The small interference (si)RNA sequence of ABCE1 was designed and synthesized to transfect the EC109 cells by electroporation. The mRNA and protein expression levels of ABCE1 were then detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR) and western blot analysis. The analysis of the cell cycle and apoptosis was performed using flow cytometry. The effect of silencing the ABCE1 gene on the proliferation, migration and invasive ability of the EC109 human esophageal cancer cells were assessed using a Cell counting kit-8 (CCK-8) and with proliferation, wound-healing and cell invasion assays. The mRNA and protein expression levels of ABCE1 were significantly lower in the experimental group compared with the control group (P<0.05). The apoptotic rate of the experimental group was markedly higher than the control group and blank group (P<0.01). The CCK-8 proliferation assay revealed that, compared with the control and blank groups, the proliferation of the EC109 cells in the experimental group was significantly inhibited (P<0.05). The wound healing assay revealed that the migration capacity of the cells in the experimental group was significantly decreased (P<0.05). The Transwell chamber assay demonstrated that the invasive ability of the EC109 cells in the experimental group was significantly decreased (P<0.01). These results revealed that ABCE1 is closely associated with cell proliferation, invasion and migration in esophageal cancer and silencing the ABCE1 gene by electroporation can significantly reduce the proliferation, invasion and migration capacity of EC109 cells in vitro.

Radiosensitivity enhancement by arsenic trioxide in conjunction with hyperthermia in the EC-1 esophageal carcinoma cell line.

OBJECTIVE: To explore the effect on radiosensitivity of arsenic trioxide (As203) in conjunction with hyperthermia on the esophageal carcinoma EC-1 cell line. METHOD: Inhibition of EC-1 cell proliferation at different concentrations of As203 was assessed using the methyl thiazolyl blue colorimetric method (MTT method), with calculation of IC50 value and choice of 20% of the IC50 as the experimental drug concentration. Blank control, As203, hyperthermia, radiotherapy group, As203 + hyperthermia, As203 + radiotherapy, hyperthermia + radiotherapy and As203 + hyperthermia + radiotherapy groups were established, and the cell survival fraction (SF) was calculated from flat panel colony forming analysis, and fitted by the 'multitarget click mathematical model'. Flow cytometry (FCM) was used to detect changes in cell apoptosis and the cell cycle. RESULTS: As203 exerted inhibitory effects on proliferation of esophageal carcinoma EC-1 cells, with an IC50 of 18.7 µmol/L. After joint therapy of As203 + hyperthermia + radiotherapy, the results of FCM showed that cells could be arrested in the G2/M phase, and as the ratio of cells in G0/G1 and S phases decreased, cell death became more pronounced. CONCLUSION: As203 and hyperthermia exert radiosensitivity effects on esophageal carcinoma EC-1 cells, with synergy in combination. Mechanistically, As203 and hyperthermia mainly influence the cell cycle distribution of EC-1 esophageal carcinoma cells, decreasing the repair of sublethal damage and inducing apoptosis, thereby enhancing the killing effects of radioactive rays.

[Analysis of prognostic factors in 68 patients with cancer of unknown primary site].

OBJECTIVE: The aim of this study was to analyze the clinical characteristics and prognostic factors in patients with cancer of unknown primary site (CUP). METHODS: The clinical and follow-up data of 68 CUP patients (46 adenocarcinoma patients, 22 squamous cell carcinoma patients), were retrospectively analyzed. Univariate and multivariate analysis were conducted to determine the correlation of survival with clinical features, tumor markers, blood test, liver function and so on. RESULTS: The median survival time of the 68 CUP patients was 123 days. The results from univariate Cox regression analysis showed that the prognostic factors were related to a performance status, presence or absence of liver metastases, the number of metastatic sites, carcinoembryonic antigen (CEA), lactate dehydrogenase (LDH), hypoalbuminemia, hypohemoglobinemia and lymphocyte count. Multivariate Cox regression analysis of the clinical factors identified that a performance status (PS) ≥ 2, liver metastasis, elevated serum carcinoembryonic antigen (CEA) and lactate dehydrogenase (LDH) levels, hypoalbuminemia (< 35 g/L) and lymphopenia (≤ 0.7 × 10(9)/L) were significant independent unfavorable predictive factors. Based on the number of the unfavorable predictive factors, we divided all the patients into three subgroups: subgroup involving 0-1 unfavorable factor, subgroup involving 2 - 3 unfavorable factors and subgroup involving 4 - 6 unfavorable factors. The median survival time was 390 days, 138 days and 77 days, respectively, in the 3 subgroups. Compared with the other two groups, the survival of the subgroup involving 0 - 1 unfavorable factor was significantly longer (P < 0.05), the survival between the subgroup involving 2 - 3 unfavorable factors and subgroup involving 4 - 6 unfavorable factors was not significantly different (P > 0.05). CONCLUSIONS: A performance status ≥ 2, liver metastasis, elevated serum carcinoembryonic antigen and lactate dehydrogenase levels, hypoalbuminemia and lymphopenia are independent unfavorable prognostic factors in patients with cancer of unknown primary site. The patients who had more than 2 unfavorable prognostic factors have a worse prognosis.

Faster rates of post-puberty kidney deterioration in males is correlated with elevated oxidative stress in males vs females at early puberty.

BACKGROUND: Post-puberty deterioration of kidneys is more rapid in males than in females. To reveal the underlying molecular mechanisms for this difference, we analyzed gender-dependent gene expression in kidneys of three groups of 36 day-old rats. RESULTS: The number of genes exhibiting gender-dependent expression was highly influenced by the genetic background of the rat group examined. 373, 288 and 79 genes showed differential gene expression between males and females (p = 0.001) in US, Mhm and Mhm*BN rats, respectively. Of all gender dependently expressed genes, only 39 genes were differentially expressed in all tested groups and the direction of expression change was the same for those genes for all groups. The gene expression profile suggests higher metabolic and transport activities, enhanced cell proliferation, elevated oxidative stress, and altered vascular biology in males. Furthermore, elevated levels of superoxide anion (two- to three-fold) in males compared to females were detected at early puberty, but neither at pre-puberty nor at late puberty/early adulthood. CONCLUSION: Our data suggest that early puberty, with gender-related elevation in oxidative stress in males, is a key compromising factor on kidneys in males.