Rechallenge of immune checkpoint inhibitors in advanced non-small cell lung cancer.

Immune checkpoint inhibitor (ICI) rechallenge in non-small cell lung cancer (NSCLC) is a promising therapeutic strategy. The situation for ICI rechallenge can be divided into three categories: adverse events (AEs); resistance to ICIs, and rechallenge becomes compulsive because of tumor relapse while the patients had completed a 2 year course of immunotherapy. However, these categories are still controversial and should be explored further. Through voting at the 6th Straits Summit Forum on Lung Cancer, in this study we summarize the consensus of 147 experts in ICI rechallenges. A total of 97.74% experts agreed to rechallenge; 48.87% experts rechallenge with the original drug, and the others rechallenge with a different drug; 40.3% agreed to rechallenge directly after progression; 88.06% experts agreed to ICI rechallenge with a combination regimen; and factors such as previous performance status score, PD-1 expression, and age should also be considered. Understanding the the clinical studies in ICI rechallenge could bring us one step closer to understanding the consensus. In patients with advanced NSCLC who have suffered recurrent or distant metastasis after immunotherapy, the option of rechallenge with ICIs is a promising treatment option.

Clinical definition of secondary resistance to immunotherapy in non-small cell lung cancer.

Immune checkpoint inhibitors (PD-1/PD-L1 and CTLA-4 blockade) have revolutionized the treatment landscape in non-small cell lung cancer (NSCLC). Secondary resistance to immunotherapy (IO), which poses a substantial challenge in clinical settings, occurs in several initial responders. Currently, new treatment approaches have been extensively evaluated in investigational studies for these patients to tackle this difficult problem; however, the lack of consistency in clinical definition, uniform criteria for enrollment in clinical trials, and interpretation of results remain significant hurdles to progress. Thus, our expert panel comprehensively synthesized data from current studies to propose a practical clinical definition of secondary resistance to immunotherapy in NSCLC in metastatic and neoadjuvant settings. In addition to patients who received IO alone (including IO-IO combinations), we also generated a definition for patients treated with chemotherapy plus IO. This consensus aimed to provide guidance for clinical trial design and facilitate future discussions with investigators. It should be noted that additional updates in this consensus are required when new data is available.

Snapshot of proteomic changes in Aspergillus oryzae during various stages of fermentative processing of pea protein isolate.

Pea (Pisum sativum) is one of the most abundant and sustainable alternate source of protein. Although pea proteins have good quantities of most of the essential amino acids, they have a limited supply of tryptophan, methionine and cysteine. Moreover, pea proteins have poor techno-functional properties compared to proteins from animal sources, limiting their use in certain food applications. Bioprocessing techniques like solid-state fermentation (SSF) and enzymatic processing have been explored to improve the nutrient profile and functionality of pea proteins. However, there is a lack of information about proteomic changes in the food matrix during fermentation of the pea substrate. In this research, samples during SSF of pea protein isolate with Aspergillus oryzae were used for shotgun mass spectrometry (LC-MS/MS) analysis to identify the underlying functional pathways which play direct or indirect roles in enabling the colonization of the substrate leading to potential improvement of functional and nutritional value of pea protein. Results revealed the identity of A. oryzae proteins involved in different metabolic pathways that differed during various stages of SSF. Among them, methionine synthase was identified as an abundant protein, which catalyzes methionine biosynthesis. This might suggest how fermentation processes could be used to improve the presence of sulfur containing amino acids to rebalance the essential amino acid profile and improve the nutritional quality of pea proteins.

Micro-CT study on isolated teeth with hereditary dentin defects.

OBJECTIVES: To construct the three-dimensional structure of the isolated teeth of patients with dentinogenesis imperfecta type Ⅱ (DGI-Ⅱ) and dentin dysplasia type Ⅰ (DD-Ⅰ) by using Micro-CT and explore internal structure and hard tissue mineralization density. METHODS: The three-dimensional structures of the third molars collected from patients with DGI-Ⅱ and DD-Ⅰ and healthy individuals of the same age were reconstructed by using Micro-CT (Mimics 17.0). The internal structures of the affected teeth along the sagittal and transverse planes were observed. The grayscale values of the enamel, crown dentin, and root dentin were calculated. Then, the mineralization densities of the different parts of the teeth of the three groups were analyzed. RESULTS: The detailed three-dimensional models of the mandibular third molars with hereditary dentin defects were successfully constructed. The models contained the models of the enamel cap, dentin core, and pulp cavity. Sagittal and transverse section scans revealed that in patients with DGI-Ⅱ, the pulp cavity was incompletely calcified and the root canal was narrow, whereas in those with DD-Ⅰ, the pulp cavity and root canal were obliterated and the root of the tooth was absent. The analysis of the grayscale values showed that compared with those in the healthy group, the grayscale values of the enamel, crown dentin, and root dentin were lower in the DGI-Ⅱ and DD-Ⅰ groups (P<0.01). No significant differences in the grayscale values of the enamel and crown dentin were found between the DGI-Ⅱ and DD-Ⅰ groups (P>0.05), whereas the grayscale value of the root dentin showed statistically significant differences between the two groups (P<0.01). CONCLUSIONS: The application of Micro-CT provided a simple and accurate method for the three-dimensional structure reconstruction and quantitative analysis of the mineralization density of isolated teeth with hereditary dentin defects. Although the dentin mineralization density of DGI-Ⅱ and DD-Ⅰ teeth decreased, the decrement shown by DD-Ⅰ teeth was more significant than that shown by DGI-Ⅱ teeth. The pulp cavity had abnormal calcifications, and the root canal was narrow or even occluded.

Minimum inhibitory concentrations of commonly used antibiotics against Helicobacter Pylori: A multicenter study in South China.

AIM: To determine the minimum inhibitory concentrations (MICs) of commonly used antibiotics against Helicobacter Pylori (H. pylori) in South China and compare their resistance rates by using EUCAST breakpoints and other breakpoints. METHODS: Patients who had not previously received H. pylori treatment in clinical centers in South China were enrolled in this study from 2017 to 2020. Gastric biopsies were obtained for H. pylori culture. The MICs of amoxicillin (AMX), clarithromycin (CLA), metronidazole (MTZ), levofloxacin (LEV), tetracycline (TET) and furazolidone (FZD) were tested by broth microdilution method and assessed by two different breakpoints. ATCC43504 standard strain served as a control. RESULTS: A total of 208 H. pylori strains were isolated from patients' biopsy samples. The MICs of AMX, CLA, MTZ, LEV, TET and FZD for H. pylori were 0.0156-256mg/L (MIC50 0.125mg/L, MIC90 4mg/L), 0.0156- >256 mg/L (MIC50 0.0312mg/L, MIC90 64mg/L), 0.0156- >256mg/L (MIC50 8mg/L, MIC90 256mg/L), 0.0156-256mg/L (MIC50 0.25mg/L, MIC90 16mg/L), 0.0156-256mg/L (MIC50 0.0625mg/L, MIC90 4mg/L), and 0.0156- >256mg/L (MIC50 0.0312mg/L, MIC90 2mg/L), respectively. The MICs of AMX, CLA, MTZ, LEV, TET and FZD for ATCC43504 strain were 0.25mg/L, 0.0625mg/L, 64mg/L, 0.5mg/L, 1mg/L and 0.25mg/L, respectively. The resistance rate of FZD was 11.05%. The overall resistance rates according to EUCAST breakpoints and other breakpoints were 57.21% and 14.90% for AMX (p<0.001), 38.94% and 38.94% for CLA (p = 1), 39.42% and 50.96% for MTZ (p<0.001), 12.98% and 10.58% for TET (p = 0.025), 35.10% and 35.10% for LEV (p = 1), respectively. CONCLUSIONS: Our results demonstrate that AMX, FZD, and TET, but not MTZ, CLR or LEV, showed good anti-H. pylori activity in vitro in South China. When different breakpoints were used, similar results were found with CLA, and LEV, but not with AMX, MTZ, or TET.

Underwater vs conventional endoscopic mucosal resection in treatment of colorectal polyps: A meta-analysis.

BACKGROUND: Underwater endoscopic mucosal resection (UEMR) of colorectal lesions is emerging as an alternative method to conventional endoscopic mucosal resection (EMR); however, it is still controversial whether there is a difference in the effectiveness between UEMR and EMR. AIM: To evaluate the effectiveness and safety of UEMR in the treatment of colorectal polyps. METHODS: Clinical studies comparing the effectiveness or safety of UEMR in the treatment of colorectal polyps were searched in medical databases, including PubMed, Embase, Cochrane Library, CNKI, and Wanfang Data, monographs, theses, and papers presented at conferences. Statistical analyses were performed using Revman 5.3 software. RESULTS: Seven non-randomized controlled trials and one randomized controlled trial met the inclusion criteria. In total, 1382 patients (1511 polyps) were included in the study, including 722 who received UEMR and 789 who received EMR. In the UEMR and EMR groups, the en bloc resection rates were 85.87% and 73.89%, respectively, with a relative risk (RR) value of 1.14 (95% confidence interval [CI]: 1.01-1.30; P < 0.05). In the sub-group analysis, the en bloc resection rate showed no statistically significant difference between the EMR and UEMR groups for polyps less than 20 mm in diameter. However, a statistically significant difference was found between the EMR and UEMR groups for polyps equal to or greater than 20 mm in diameter. The post-endoscopic resection recurrence rates at 3-6 mo of the UEMR and EMR groups were 3.26% and 15.17%, respectively, with an RR value of 0.27 (95%CI: 0.09-0.83; P < 0.05). The post-endoscopic resection recurrence rates of UEMR and EMR at 12 mo were 6.25% and 14.40%, respectively, with an RR value of 0.43 (95%CI: 0.20-0.92; P < 0.05). Additionally, the incidence of adverse events was 8.17% and 6.21%, respectively, with an RR value of 1.07 (95%CI: 0.50-2.30; P > 0.05). CONCLUSION: UEMR is an effective technique for colorectal polyps and appears to have some advantages over EMR, particularly with regard to some treatment outcomes.

Comparative effect of tenuazonic acid, diuron, bentazone, dibromothymoquinone and methyl viologen on the kinetics of Chl a fluorescence rise OJIP and the MR820 signal.

In this study, the comparative effect of TeA, DCMU, bentazone, DBMIB and MV on prompt fluorescence and the MR820 signal was simultaneously analyzed to provide an insight into how to elucidate their precise influence on Ageratina adenophora photosystems. The herbicides that interrupt electron transport beyond QA, such as TeA, DCMU and bentazone, mainly increased the J-step level of fluorescence rise kinetics as a result of accumulation of QA-, but showed differences in detail. The IP phase disappeared in the presence of DCMU and bentazone with a significant increase in FO value. TeA treatment retained the IP phase with lowering FM. As an inhibitor of plastoquinone re-oxidation, DBMIB increased the I-step (IP phase almost unnoticable) without changing FO and FM values. MV blocking PSI electron transfer through intercepting electrons from the FeS clusters suppressed the IP phase by decreasing the P level. Considering the WIP kinetics, TeA and DBMIB also affected PSI activity. After DCMU and MV treatment, the major change in the MR820 kinetics was the loss of the slow phase due to the complete prevention of electron movement from PSII to re-reduce PC+ and P700+. TeA, bentazone and DBMIB clearly suppressed the MR820 slow phase and decreased the re-reduction rate of PC+ and P700+ (Vred), significantly. However, there were still parts of electrons being donated to PC+ and P700+, showing a smaller slow phase and PC+ and P700+ re-reduction rate. Additionally, TeA and DBMIB also somewhat declined the fast phase and PC and P700 oxidation rate (Vox).

VPS4B mutation impairs the osteogenic differentiation of dental follicle cells derived from a patient with dentin dysplasia type I.

A splicing mutation in VPS4B can cause dentin dysplasia type I (DD-I), a hereditary autosomal-dominant disorder characterized by rootless teeth, the etiology of which is genetically heterogeneous. In our study, dental follicle cells (DFCs) were isolated and cultured from a patient with DD-I and compared with those from an age-matched, healthy control. In a previous study, this DD-I patient was confirmed to have a loss-of-function splicing mutation in VPS4B (IVS7 + 46C > G). The results from this study showed that the isolated DFCs were vimentin-positive and CK14-negative, indicating that the isolated cells were derived from the mesenchyme. DFCs harboring the VPS4B mutation had a significantly higher proliferation rate from day 3 to day 8 than control DFCs, indicating that VPS4B is involved in cell proliferation. The cells were then replenished with osteogenic medium to investigate how the VPS4B mutation affected osteogenic differentiation. Induction of osteogenesis, detected by alizarin red and alkaline phosphatase staining in vitro, was decreased in the DFCs from the DD-I patient compared to the control DFCs. Furthermore, we also found that the VPS4B mutation in the DD-I patient downregulated the expression of osteoblast-related genes, such as ALP, BSP, OCN, RUNX2, and their encoded proteins. These outcomes confirmed that the DD-I-associated VPS4B mutation could decrease the capacity of DFCs to differentiate during the mineralization process and may also impair physiological root formation and bone remodeling. This might provide valuable insights and implications for exploring the pathological mechanisms underlying DD-I root development.

Candidate genes for predicting the survival of patients with gastric cancer: a study based on The Cancer Genome Atlas (TCGA) database.

BACKGROUND: Gastric cancer (GC) is the second most frequent cause of cancer-related mortality in the world, and the five-year survival rate for GC remains very low universally. In recent years, it has become a consensus that genetic changes are associated with carcinogenesis of GC, and precision medicine based on genetic changes is one of the most popular treatments for GC patients. However, the association between some genes and GC-related protein signaling pathways is still not well understood. This study revealed that seven genes were closely related to the survival probability in GC patients. METHODS: We downloaded the gene expression data of GC patients from The Cancer Genome Atlas (TCGA) databases, and integrated bioinformatic analysis was performed, such as differential gene expression analysis, including Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) pathways analyses, as well as survival analysis. The r package "survival" was used to analyze the Kaplan-Meier survival analysis, which showed the associations between specific gene expressions and the outcomes of patients with GC to identify which genes could be potential prognostic biomarkers. RESULTS: This study revealed that seven genes: alcohol dehydrogenase 4 (ADH4), histamine receptor H3 (HRH3), neuropeptide Y2 receptor (NPY2R), apolipoprotein AI (APOA1), N-acetylgalactosaminyltransferase 14 (GALNT14), leucine-rich repeats and IQ motif containing 1 (LRRIQ1), and coiled-coil-domain-containing 57 (CCDC57). These seven genes were closely related to the survival probability of GC patients (P<0.05). CONCLUSIONS: Our study found seven genes which could be considered as candidate prognostic biomarkers and therapeutic targets.

Diagnostic application of water exchange colonoscopy: A meta-analysis of randomized controlled trials.

BACKGROUND: Few well-designed studies have investigated water exchange colonoscopy (WE). We performed a meta-analysis to comprehensively evaluate the clinical utility of WE based on high-quality randomized controlled trials (RCTs) and to compare the impacts of WE, water immersion colonoscopy (WI), and gas-insufflation colonoscopy. METHODS: We searched the Cochrane Library, MEDLINE, Embase, PubMed, Elsevier, CNKI, VIP, and Wan Fang Data for RCTs on WE. We analyzed the results using fixed- or random-effect models according to the presence of heterogeneity. Publication bias was assessed by funnel plots. RESULTS: Thirteen studies were eligible for this meta-analysis. The colonoscopic techniques included WE as the study group, and WI and air- or CO2-insufflation colonoscopy as control groups. WE was significantly superior to the control procedures in terms of adenoma detection rate, proportion of painless unsedated colonoscopy procedures, and cecal intubation rate according to odds ratios. WE was also significantly better in terms of maximal pain score and patient satisfaction score according to mean difference. CONCLUSIONS: WE can remarkably improve the adenoma detection rate, proportion of painless unsedated colonoscopy procedures, patient satisfaction, and cecal intubation rate, as well as reducing the maximal pain score in patients undergoing colonoscopy.

Entire Peroxidation Reaction System of Myeloperoxidase Correlates with Progressive Low-Density Lipoprotein Modifications via Reactive Aldehydes in Atherosclerotic Patients with Hypertension.

BACKGROUND/AIMS: Reactive oxygen species (ROS) contribute to the dysfunction of serum lipoproteins, which triggers lipid metabolism abnormalities in the development of atherosclerosis and hypertension. Myeloperoxidase (MPO) is involved in ROS modifications, triggering lipid peroxidation and aldehyde formation. However, the relationship between the entirety of the MPO reaction system and oxidative modification of serum lipoproteins in atherosclerotic patients with hypertension remains unclear. METHODS: We measured MPO activity (peroxidation and chlorination), 4-hydroxynonenal-modified low-density lipoprotein (HNE-LDL), malondialdehyde-modified low-density lipoprotein (MDA-LDL), H2O2, reduced glutathione (GSH), and oxidized glutathione (GSSG) using a corresponding commercial kit in atherosclerotic patients with hypertension and healthy participants. We used Spearman's correlation analysis to investigate the correlation between MPO activity and the levels of these oxidative and anti-oxidative stress-related indices and performed response surface regression to investigate the relationship between the MPO reaction system and the levels of HNE-LDL, MDA-LDL, and the GSH/GSSG ratio. RESULTS: Our results showed no association between the levels of MPO peroxidation activity, MPO chlorination activity, H2O2, and Cl- and those of HNE-LDL, MDA-LDL, GSH, and GSSG, and the GSH/GSSG ratio in healthy participants. In addition, no effects of the peroxidation reaction system of MPO (PRSM) and the chlorination reaction system of MPO (CRSM) on GSH/GSSG were found in this investigation. However, we found that the PRSM rather than the CRSM correlated with progressive low-density lipoprotein (LDL) modifications by HNE-LDL and MDA-LDL in atherosclerotic patients with hypertension. CONCLUSION: The PRSM rather than the CRSM correlated with progressive LDL modifications via reactive aldehydes in atherosclerotic patients with hypertension. Further investigation is warranted to evaluate whether the PRSM may serve as a potential index for monitoring LDL function in atherosclerosis and hypertension.

Association of NCOA3 polymorphisms with Dyslipidemia in the Chinese Han population.

BACKGROUND: Nuclear receptor coactivator-3 (NCOA3) is involved in various physiological processes. Emerging evidence from previous studies using animal models suggests that the NCOA3 gene (NCOA3) plays a critical role in lipid metabolism as well as adipogenesis and obesity. The present study aims to investigate the association between NCOA3 SNPs and dyslipidemia in the Chinese Han population. METHODS: Five hundred and twenty-nine (529) Chinese Han subjects were recruited. Four tag SNPs (rs2425955G > T, rs6066394T > C, rs10485463C > G, and rs6094753G > A) in NCOA3, selected from the HapMap website, were genotyped using MALDI-TOF mass spectrometry. Data analysis was performed using SPSS 16.0, SNPStats and haploview 4.2. RESULTS: Four SNPs (rs2425955, rs6066394, rs10485463, and rs6094753) were associated with triglyceride levels. Except for SNP rs10485463, genotype distributions and allele frequencies of the other three NCOA3 SNPs (rs2425955, rs6066394, and rs6094753) were significantly different between hypertriglyceridemia subjects and normal group. Significant differences were also observed in allele frequencies and genotype distributions of SNP rs10485463 between low-HDL cholesterolemia subjects and normal group. Carriers of rs2425955 T allele had a lower risk of hypertriglyceridemia compared to GG genotype. Similar results were observed from rs6094753. Subjects with rs6066394 CT genotype had a lower risk of hypertriglyceridemia than those with the TT genotype; however, CC and TT genotypes showed no significant difference in the risk of hypertriglyceridemia. Similar results were found in the association between rs6066394 and hypercholesterolemia. The variant alleles of rs2425955, rs6066394 and rs6094753 were associated with a lower risk of hypertriglyceridemia compared with the wild-type alleles. The G allele of rs10485463 was associated with an increased risk of low-HDL cholesterolemia. In the log-additive model the association between rs2425955 and hypertriglyceridemia remained significant after Bonferroni correction, and genotypes with variant alleles were associated with a lower risk of hypertriglyceridemia. CONCLUSIONS: In summary, this study demonstrated that variation in NCOA3 might influence the risk of dyslipidemia and serum lipid levels in Chinese Han population.

Doxycycline Induces Apoptosis and Inhibits Proliferation and Invasion of Human Cervical Carcinoma Stem Cells.

BACKGROUND: Cancer stem cells (CSCs) are proposed to be responsible for high recurrence rate in cervical carcinoma. Reagents that can suppress the proliferation and differentiation of CSCs would provide new opportunities to fight against tumor recurrence. Doxycycline has been reported as a potential anti-cancer compound. However, few studies investigated its inhibitory effect against cervical cancer stem cells. METHODS: HeLa cells were cultured in cancer stem cell conditional media in a poly-hema-treated dish. In this non-adhesive culture system, HeLa cells were treated with cisplatin until some cells survived and formed spheroids, which were then collected and injected into the immunodeficient mice. Cisplatin was administered every three days for five times. The tumor xenografts with CSC enrichment were cultured in cancer stem cell specific medium again to form tumorsphere, which we called HeLa-CSCs. Expression of cancer stem cell markers in HeLa-CSCs was measured by flow cytometry and qPCR. HeLa-CSCs were then treated with doxycycline. Proliferation and differentiation rates were determined by the size of spheres formed in vitro and tumor formed in vivo. RESULTS: We developed a new strategy to selectively enrich CSCs from human cervical carcinoma cell line HeLa, and these HeLa-CSCs are CD133+/CD49f+ cell populations with significantly enhanced expression of stem cell markers. When these HeLa-CSCs were treated with doxycycline, the colony formation, proliferation, migration and invasion, and differentiation were all suppressed. Meanwhile, stem cell markers SOX-2, OCT-4, NANOG, NOTCH and BMI-1 decreased in doxycycline treated cells, so as the surface markers CD133 and CD49f. Furthermore, proliferation markers Ki67 and PCNA were also decreased by doxycycline treatment in the in vivo xenograft mouse model. CONCLUSIONS: Cancer stem cells are enriched from sphere-forming and chemoresistant HeLa-derived tumor xenografts in immunodeficient mice. Doxycycline inhibits proliferation, invasion, and differentiation, and also induces apoptosis of these HeLa-CSCs in vitro and in vivo.

Antiproliferative quillaic acid and gypsogenin saponins from Saponaria officinalis L. roots.

Nine quillaic acid and five gypsogenin bisdesmosides were isolated from roots of Saponaria officinalis L. (Caryophyllaceae). Seven of the quillaic acid saponins possessed a 3-O-ß-D-galactopyranosyl-(1 → 2)-[ß-D-xylopyranosyl-(1 → 3)]-ß-D-glucuronopyranosyl unit, but differed from each other in oligosaccharide units linked to the C-28 ester. The five gypsogenin saponins isolated from the roots all possessed the 3-O-ß-D-galactopyranosyl-(1 → 2)-[ß-D-xylopyranosyl-(1 → 3)]-ß-D-glucuronopyranosyl unit, with their oligosaccharide units linked to the C-28 ester differing. Structures were elucidated by extensive 1D and 2D NMR spectroscopy and mass spectrometry. The saponins were evaluated for growth inhibitory activity in two human cancer cell lines and hemolytic activity in sheep red blood cells.

Digital gene expression profiling of the Phytophthora sojae transcriptome.

The transcriptome of the oomycete plant pathogen Phytophthora sojae was profiled at ten different developmental and infection stages based on a 3'-tag digital gene-expression protocol. More than 90 million clean sequence tags were generated and compared with the P. sojae genome and its 19,027 predicted genes. A total of 14,969 genes were detected, of which 10,044 were deemed reliable because they mapped to unambiguous tags. A comparison of the whole-library genes' expression patterns suggested four groups: i) mycelia and zoosporangia, ii) zoospores and cysts, iii) germinating cysts, and iv) five infection site libraries (IF1.5 to IF24h). The libraries from the different groups showed major transitional shifts in gene expression. From the ten libraries, 722 gene expression?pattern clusters were obtained and the top 16 clusters, containing more than half of the genes, comprised enriched genes with different functions including protein localization, triphosphate metabolism, signaling process, and noncoding RNA metabolism. An evaluation of the average expression level of 30 pathogenesis-related gene families revealed that most were infection induced but with diverse expression patterns and levels. A web-based server named the Phytophthora Transcriptional Database has been established.

EST analysis of hop glandular trichomes identifies an O-methyltransferase that catalyzes the biosynthesis of xanthohumol.

The glandular trichomes (lupulin glands) of hop (Humulus lupulus) synthesize essential oils and terpenophenolic resins, including the bioactive prenylflavonoid xanthohumol. To dissect the biosynthetic processes occurring in lupulin glands, we sequenced 10,581 ESTs from four trichome-derived cDNA libraries. ESTs representing enzymes of terpenoid biosynthesis, including all of the steps of the methyl 4-erythritol phosphate pathway, were abundant in the EST data set, as were ESTs for the known type III polyketide synthases of bitter acid and xanthohumol biosynthesis. The xanthohumol biosynthetic pathway involves a key O-methylation step. Four S-adenosyl-l-methionine-dependent O-methyltransferases (OMTs) with similarity to known flavonoid-methylating enzymes were present in the EST data set. OMT1, which was the most highly expressed OMT based on EST abundance and RT-PCR analysis, performs the final reaction in xanthohumol biosynthesis by methylating desmethylxanthohumol to form xanthohumol. OMT2 accepted a broad range of substrates, including desmethylxanthohumol, but did not form xanthohumol. Mass spectrometry and proton nuclear magnetic resonance analysis showed it methylated xanthohumol to 4-O-methylxanthohumol, which is not known from hop. OMT3 was inactive with all substrates tested. The lupulin gland-specific EST data set expands the genomic resources for H. lupulus and provides further insight into the metabolic specialization of glandular trichomes.

Enhancement of alkaloid production in opium and California poppy by transactivation using heterologous regulatory factors.

Genes encoding regulatory factors isolated from Arabidopsis, soybean and corn have been screened to identify those that modulate the expression of genes encoding for enzymes involved in the biosynthesis of morphinan alkaloids in opium poppy (Papaver somniferum) and benzophenanthridine alkaloids in California poppy (Eschscholzia californica). In opium poppy, the over-expression of selected regulatory factors increased the levels of PsCOR (codeinone reductase), Ps4'OMT (S-adenosyl-l-methionine:3'-hydroxy-N-methylcoclaurine 4'-O-methyltransferase) and Ps6OMT [(R,S)-norcoclaurine 6-O-methyltransferase] transcripts by 10- to more than 100-fold. These transcriptional activations translated into an enhancement of alkaloid production in opium poppy of up to at least 10-fold. In California poppy, the transactivation effect of regulatory factor WRKY1 resulted in an increase of up to 60-fold in the level of EcCYP80B1 [(S)-N-methylcoclaurine 3'-hydroxylase] and EcBBE (berberine bridge enzyme) transcripts. As a result, the accumulations of selected alkaloid intermediates were enhanced up to 30-fold. The transactivation effects of other regulatory factors led to the accumulation of the same intermediates. These regulatory factors also led to the production of new alkaloids in California poppy callus culture.

Regulation of DNA methylation on the expression of the FHIT gene contributes to cervical carcinoma cell tumorigenesis.

The purpose of this study was to determine the effect of the FHIT gene on tumorigenesis of cervical cancer. RT-PCR and MTT were used to detect the expression of FHIT and cell proliferation respectively. Flow cytometry was used to test cell cycle and cell apoptosis. The expression of FHIT was not induced at all four cervical cancer cells treated with demethylating agent 5-aza-2'-deoxycytidine (5-Aza-CdR). However, a constant level of FHIT expression was detected in the human umbilical vein endothelial cell before and after 5-aza-dC treatment. The proliferation of all four cervical cancer cells was inhibited evidently when treated with 5-aza-dC and the inhibiting rate of cell growth along with the increasing concentration of 5-aza-dC. There was no obvious inhibiting effect on the growth of the human umbilical vein endothelial cell treated with 5-aza-dC. An increasing G1 phase and high apoptosis rate were detected in all four cervical cancer cells. However, a negligible change was seen in the human umbilical vein endothelial cell. These results suggest that aberrant methylation of the FHIT gene might be a key mechanism for silenced FHIT gene, which could be reactivated and whose tumor suppressing function could be restored by demethylating agent treatment.