HEIH Promotes Malignant Progression of Gastric Cancer by Regulating STAT3-Mediated Autophagy and Glycolysis.

To study the clinical value of HEIH hyperexpression in gastric cancer and the molecular mechanism of promoting malignant proliferation of gastric cancer cells, qRT-PCR was used to detect the expression of HEIH in gastric cancer and nontumor gastric tissues. HEIH interference sequence was constructed to downregulate HEIH expression in MGC-803 and BGC-823 cell lines. CCK8, clonogenesis, and Transwell assay were used to detect the effects of HEIH on proliferation and invasion of tumor cells. The protein levels of STAT3, p-STAT3, P62, and LC3 were detected by Western blotting. The results showed that HEIH was highly expressed in gastric cancer (P < 0.01). Interference of HEIH expression in MGC-803 and BGC-823 cells reduced the proliferation and invasion of gastric cancer cells, and the results were statistically significant (P < 0.05). HEIH acts as a miRNA sponge for miR-4500. HEIH promotes gastric cancer development by inhibiting miR-4500. STAT3 is a downstream target of miR-4500. HEIH inhibits autophagy and promotes glycolysis. In conclusion, HEIH is highly expressed in gastric cancers. HEIH promotes malignant proliferation and development of gastric cancer cells. HEIH may be a new candidate site for pathological diagnosis and molecular drug therapy for future clinical treatment of gastric cancer.

The URL1-ROC5-TPL2 transcriptional repressor complex represses the ACL1 gene to modulate leaf rolling in rice.

Moderate leaf rolling is beneficial for leaf erectness and compact plant architecture. However, our understanding regarding the molecular mechanisms of leaf rolling is still limited. Here, we characterized a semi-dominant rice (Oryza sativa L.) mutant upward rolled leaf 1 (Url1) showing adaxially rolled leaves due to a decrease in the number and size of bulliform cells. Map-based cloning revealed that URL1 encodes the homeodomain-leucine zipper (HD-Zip) IV family member RICE OUTERMOST CELL-SPECIFIC 8 (ROC8). A single-base substitution in one of the two conserved complementary motifs unique to the 3'-untranslated region of this family enhanced URL1 mRNA stability and abundance in the Url1 mutant. URL1 (UPWARD ROLLED LEAF1) contains an ethylene-responsive element binding factor-associated amphiphilic repression motif and functions as a transcriptional repressor via interaction with the TOPLESS co-repressor OsTPL2. Rather than homodimerizing, URL1 heterodimerizes with another HD-ZIP IV member ROC5. URL1 could bind directly to the promoter and suppress the expression of abaxially curled leaf 1 (ACL1), a positive regulator of bulliform cell development. Knockout of OsTPL2 or ROC5 or overexpression of ACL1 in the Url1 mutant partially suppressed the leaf-rolling phenotype. Our results reveal a regulatory network whereby a transcriptional repression complex composed of URL1, ROC5, and the transcriptional corepressor TPL2 suppresses the expression of the ACL1 gene, thus modulating bulliform cell development and leaf rolling in rice.

Narrow Leaf21, encoding ribosomal protein RPS3A, controls leaf development in rice.

Leaf morphology influences photosynthesis, transpiration, and ultimately crop yield. However, the molecular mechanism of leaf development is still not fully understood. Here, we identified and characterized the narrow leaf21 (nal21) mutant in rice (Oryza sativa), showing a significant reduction in leaf width, leaf length and plant height, and increased tiller number. Microscopic observation revealed defects in the vascular system and reduced epidermal cell size and number in the nal21 leaf blade. Map-based cloning revealed that NAL21 encodes a ribosomal small subunit protein RPS3A. Ribosome-targeting antibiotics resistance assay and ribosome profiling showed a significant reduction in the free 40S ribosome subunit in the nal21 mutant. The nal21 mutant showed aberrant auxin responses in which multiple auxin response factors (ARFs) harboring upstream open-reading frames (uORFs) in their 5'-untranslated region were repressed at the translational level. The WUSCHEL-related homeobox 3A (OsWOX3A) gene, a key transcription factor involved in leaf blade lateral outgrowth, is also under the translational regulation by RPS3A. Transformation with modified OsARF11, OsARF16, and OsWOX3A genomic DNA (gDNA) lacking uORFs rescued the narrow leaf phenotype of nal21 to a better extent than transformation with their native gDNA, implying that RPS3A could regulate translation of ARFs and WOX3A through uORFs. Our results demonstrate that proper translational regulation of key factors involved in leaf development is essential to maintain normal leaf morphology.

CircCSNK1G1 Contributes to the Development of Colorectal Cancer by Increasing the Expression of MYO6 via Competitively Targeting miR-455-3p.

BACKGROUND: Numerous circular RNAs (circRNAs) are functionally investigated in various human cancers, including colorectal cancer (CRC). In this study, we explored the function of circCSNK1G1 and mechanism of action in CRC, aiming to provide evidence for circCSNK1G1 involving in CRC pathogenesis. METHODS: The expression of circCSNK1G1, miR-455-3p and Myosin VI (MYO6) were examined using quantitative real-time polymerase chain reaction (qRT-PCR). The functions of circCSNK1G1 on cell proliferation, apoptosis, cycle and migration/invasion were investigated using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, colony formation assay, flow cytometry assay and transwell assay, respectively. The targeted relationship between miR-455-3p and circCSNK1G1 or MYO6 predicted by bioinformatics analysis was validated using dual-luciferase reporter assay and RNA pull-down assay. The role of circCSNK1G1 was also explored in nude mice in vivo. RESULTS: The expression of circCSNK1G1 and MYO6 was elevated, while the expression of miR-455-3p was declined in CRC tissues and cells. Silencing circCSNK1G1 inhibited CRC cell proliferation, migration and invasion and induced cell apoptosis and cell cycle arrest. MiR-455-3p was a target of circCSNK1G1, and miR-455-3p could bind to MYO6. CircCSNK1G1 positively regulated MYO6 expression by targeting miR-455-3p. Inhibition of miR-455-3p reversed the effects of circCSNK1G1 silencing in CRC cells. Besides, miR-455-3p restoration blocked CRC cell growth and metastasis, which were abolished by MYO6 overexpression. Moreover, circCSNK1G1 regulated the miR-455-3p/MYO6 axis to block tumor growth in vivo. CONCLUSION: CircCSNK1G1 participated in the progression of CRC partly by modulating the miR-455-3p/MYO6 network, which provided a theoretical basis for circCSNK1G1 involving in CRC pathogenesis, hinting that circCSNK1G1 might be a useful biomarker for CRC treatment.

Reduction of ATPase activity in the rice kinesin protein Stemless Dwarf 1 inhibits cell division and organ development.

Several kinesins, the ATP-driven microtubule (MT)-based motor proteins, have been reported to be involved in many basic processes of plant development; however, little is known about the biological relevance of their ATPase activity. Here, we characterized the Oryza sativa (rice) stemless dwarf 1 (std1) mutant, showing a severely dwarfed phenotype, with no differentiation of the node and internode structure, abnormal cell shapes, a shortened leaf division zone and a reduced cell division rate. Further analysis revealed that a substantial subset of cells was arrested in the S and G2/M phases, and multinucleate cells were present in the std1 mutant. Map-based cloning revealed that STD1 encodes a phragmoplast-associated kinesin-related protein, a homolog of the Arabidopsis thaliana PAKRP2, and is mainly expressed in the actively dividing tissues. The STD1 protein is localized specifically to the phragmoplast midzone during telophase and cytokinesis. In the std1 mutant, the substitution of Val-40-Glu in the motor domain of STD1 significantly reduced its MT-dependent ATPase activity. Accordingly, the lateral expansion of phragmoplast, a key step in cell plate formation, was arrested during cytokinesis. Therefore, these results indicate that the MT-dependent ATPase activity is indispensible for STD1 in regulating normal cell division and organ development.

Genetic variants in miRNA machinery genes associated with clinicopathological characteristics and outcomes of gastric cancer patients.

BACKGROUND: Polymorphisms in miRNA machinery genes have been proved to be related to risk or survival of several kinds of cancers, but the results are controversial and the role of these polymorphisms in gastric cancer remains uncertain. In our study, we investigated the association between five genetic variants in miRNA machinery genes ( DICER, RAN, XPO5 [name of the gene]) and clinical outcomes in Chinese gastric cancer patients. METHODS: A total of 96 patients with stage IB-III gastric cancer treated with radical gastrectomy and adjuvant chemotherapy of oxaliplatin and fluorouracils were analyzed. The MassARRAY MALDI-TOF system was used to determine the genotypes. RESULTS: DICER rs3742330 AG+GG genotype was associated with more advanced T stage compared to AA genotype ( P=0.009). More patients with XPO5 rs2257082 CC genotype had poorly differentiated tumors compared with CT+TT genotype carriers. After adjustment by age, sex, differentiation, T stage, and lymph node status, XPO5 rs2257082 CC genotype carriers were found to have worse disease-free survival than CT+TT genotype carriers (adjusted HR 3.099; 95% CI 1.270, 7.564; P=0.013), carriers of RAN rs14035 CC genotype had higher three-year OS rate than carriers of CT+TT genotype (adjusted HR 3.174; 95% CI 1.010, 9.973; P=0.048). CONCLUSIONS: These results indicated that genetic variants in miRNA machinery genes might be associated with the clinicopathological features and prognosis of completely resected gastric cancer patients.

DROSHA rs10719 T>C is associated with lymph node metastasis and clinical stage of gastric cancer patients.

It has been proved that polymorphisms in DROSHA are related to the risk and outcomes of several cancers. In our study, 97 patients with stage I-III gastric cancer treated with radical gastrectomy and adjuvant chemotherapy of oxaliplatin and fluoropyrimidines were analyzed. MassARRAY MALDI-TOF system was used to determine the genotypes. The 2-year DFS rate was 60.8% and the 3-year OS rate was 73.8%. In dominant model, we found that rs10719 TC+CC genotype carriers were less likely to develop lymph node metastasis (P=0.031). Compared with TC+CC genotype carriers, more patients with TT genotype were in stage III (P=0.021). The 3-year OS was significantly different for patients with or without lymph node metastasis (89.3% vs 63.3%, P=0.013) and for patients with stage I-III disease (100.0%, 88.6% and 55.8%, P=0.015). After the multi-variants' cox regression analysis, lymph node status (P=0.014, RR: 9.556, 95% CI: 1.586-57.590) was found to be an independent prognostic factor for these patients. These results suggested that DROSHA rs10719 T>C may be associated with lymph node metastasis and clinical stage of gastric cancer in a Chinese population.

A Missense Mutation in the Zinc Finger Domain of OsCESA7 Deleteriously Affects Cellulose Biosynthesis and Plant Growth in Rice.

Rice is a model plant species for the study of cellulose biosynthesis. We isolated a mutant, S1-24, from ethyl methanesulfonate (EMS)-treated plants of the japonica rice cultivar, Nipponbare. The mutant exhibited brittle culms and other pleiotropic phenotypes such as dwarfism and partial sterility. The brittle culms resulted from reduced mechanical strength due to a defect in thickening of the sclerenchyma cell wall and reduced cellulose content in the culms of the S1-24 mutant. Map-based gene cloning and a complementation assay showed that phenotypes of the S1-24 mutant were caused by a recessive point mutation in the OsCESA7 gene, which encodes cellulose synthase A subunit 7. The missense mutation changed the highly conserved C40 to Y in the zinc finger domain. The OsCESA7 gene is expressed predominantly in the culm at the mature stage, particularly in mechanical tissues such as vascular bundles and sclerenchyma cells, consistent with the brittle phenotype in the culm. These results indicate that OsCESA7 plays an important role in cellulose biosynthesis and plant growth.

Polymorphism in miR-146a associated with clinical characteristics and outcomes in gastric cancer patients treated with adjuvant oxaliplatin and fluoropyrimidines.

PURPOSE: Polymorphism in miR-146a (rs2910164) has been reported to be associated with gastric cancer risk in the Chinese population. We aimed at evaluating the relationship between rs2910164 and the clinical characteristics and outcomes in stage IB-III gastric cancer patients treated with adjuvant chemotherapy after surgery. MATERIALS AND METHODS: Ninety-eight patients with stage IB-III gastric cancer treated with surgical resection followed by adjuvant chemotherapy of oxaliplatin and fluoropyrimidines were included in the analysis. Genomic DNA was extracted from peripheral blood sample of all patients. Polymerase chain reaction-based restriction fragment length polymorphism assay was used to determine the genotypes. RESULTS: The 2-year disease-free survival rate was 63%, and the 3-year overall survival (OS) rate was 73.4%. In dominant model, we found that rs2910164 GC + CC (G: guanine, C: cytosine) genotype carriers were less likely to develop lymph node metastasis (P=0.059). The 3-year OS was significantly different for patients with or without lymph node metastasis (89.3% vs 63.7%, P=0.015) and for patients with stage I-III disease (100.0%, 88.6%, and 56.9%; P=0.018). The 3-year OS for GC + CC carriers was significantly higher than for GG carriers (75.1% vs 66.7%, P=0.041). After the multivariant Cox regression analysis, histological grade (P=0.033, relative risk: 5.116, 95% confidence interval: 1.145-22.865) and lymph node status (P=0.031, relative risk: 6.648, 95% confidence interval: 1.191-37.118) were found to be independent prognostic factors for these patients. CONCLUSION: rs2910164 could be associated with the lymph node metastasis and prognosis of Chinese gastric cancer patients treated with oxaliplatin and fluoropyrimidines after surgical resection.

Characterization of a null allelic mutant of the rice NAL1 gene reveals its role in regulating cell division.

Leaf morphology is closely associated with cell division. In rice, mutations in Narrow leaf 1 (NAL1) show narrow leaf phenotypes. Previous studies have shown that NAL1 plays a role in regulating vein patterning and increasing grain yield in indica cultivars, but its role in leaf growth and development remains unknown. In this report, we characterized two allelic mutants of NARROW LEAF1 (NAL1), nal1-2 and nal1-3, both of which showed a 50% reduction in leaf width and length, as well as a dwarf culm. Longitudinal and transverse histological analyses of leaves and internodes revealed that cell division was suppressed in the anticlinal orientation but enhanced in the periclinal orientation in the mutants, while cell size remained unaltered. In addition to defects in cell proliferation, the mutants showed abnormal midrib in leaves. Map-based cloning revealed that nal1-2 is a null allelic mutant of NAL1 since both the whole promoter and a 404-bp fragment in the first exon of NAL1 were deleted, and that a 6-bp fragment was deleted in the mutant nal1-3. We demonstrated that NAL1 functions in the regulation of cell division as early as during leaf primordia initiation. The altered transcript level of G1- and S-phase-specific genes suggested that NAL1 affects cell cycle regulation. Heterogeneous expression of NAL1 in fission yeast (Schizosaccharomyces pombe) further supported that NAL1 affects cell division. These results suggest that NAL1 controls leaf width and plant height through its effects on cell division.

DWARF3 participates in an SCF complex and associates with DWARF14 to suppress rice shoot branching.

Strigolactones (SLs) are a novel class of plant hormones that inhibit shoot branching. Currently, two proteins in rice are thought to play crucial roles in SL signal transduction. DWARF14 (D14), an α/ß hydrolase, is responsible for SL perception, while DWARF3 (D3), an F-box protein with leucine-rich repeats, is essential for SL signal transduction. However, how these two proteins transmit SL signals to downstream factors remains unclear. Here, we characterized a high-tillering dwarf rice mutant, gsor300097, which is insensitive to GR24, a synthetic analog of SL. Mapping and sequencing analysis showed that gsor300097 is a novel allelic mutant of D3, in which a nonsense mutation truncates the protein from 720 to 527 amino acids. The D3 gene was strongly expressed in root, leaf, shoot base and panicle. Nuclear-localized F-box protein D3 played a role in the SCF complex by interacting with OSK1, OSK5 or OSK20 and OsCullin1. In addition, D3 associated with D14 in a GR24-dependent manner in vivo. Taken together, our findings suggested that D3 assembled into an SCF(D3) complex and associated with D14 to suppress rice shoot branching.

Acceptable but limited efficacy of capecitabine-based doublets in the first-line treatment of metastatic triple-negative breast cancer: a pilot study.

BACKGROUND: This open-label, nonrandomized phase II clinical trial investigated the efficacy of capecitabine-based doublets in the first-line treatment of metastatic triple-negative breast cancer (mTNBC). METHODS: Eligible mTNBC women with measurable diseases were recruited to receive either TX regimen (docetaxel 75 mg/m(2) i.v. on day 1 plus capecitabine 1,000 mg/m(2) b.i.d. on days 1-14 every 3 weeks) or NX regimen (vinorelbine 25 mg/m(2) i.v. on days 1 and 8 plus capecitabine 1,000 mg/m(2) b.i.d. on days 1-14 every 3 weeks) for up to 6 cycles until disease progression or unacceptable toxicity. The primary end point was objective response rate (ORR) and secondary end points included progression-free survival (PFS), overall survival (OS) and clinical benefit rate (CBR). RESULTS: Forty-five mTNBC patients, 27 in TX and 18 in NX were recruited. The total ORR was 20.0% and CBR was 40%. After a median follow-up of 28 months, PFS was 5.2 months (95% CI, 4.1-6.3 months) and OS was 18.2 months (95% CI, 8.7-27.7 months). The response rate was numerically but not statistically lower in the TX group than in the NX group (27.8 vs. 14.8%, p = 0.449). No difference was found in either PFS (4.9 vs. 5.2 months, p = 0.483) or OS (21.5 vs. 18.3 months, p = 0.964) between the two regimens. CONCLUSIONS: Although the OS seems to be reasonable, the efficacy of capecitabine-containing TX or NX regimen was limited in terms of response and PFS in mTNBC patients, suggesting capecitabine-based doublet may be acceptable but has limited potency in this subtype.