Association Between the Blood Glucose Value at PACU Discharge and Postoperative Hypoglycemia in Nondiabetic Patients With Hyperglycemia After Hysteroscopic Surgery: A Retrospective Cohort Study.

PURPOSE: The target glycemic control for nondiabetic patients in the postanesthesia care unit (PACU) after hysteroscopic surgery remains unclear. Our goal is to determine the optimal level of glycemic control by finding the relationship between blood glucose level (BGL) leaving the PACU and postoperative hypoglycemia in nondiabetic patients. DESIGN: This retrospective cohort study was conducted at a comprehensive tertiary hospital in Chongqing, China between June 2018 and December 2020. METHODS: The target independent and dependent variables were BGL leaving the PACU and postoperative hypoglycemia, respectively. The primary outcome was the incidence of hypoglycemia. Logistic regression was used to explore the association between discharge BGL and hypoglycemia. The optimal glycemic control range was determined by using the receiver operating characteristic (ROC) curve. FINDINGS: Prior to insulin use, BGL in the insulin-using subgroup might be as high as 20 mmol/L. Hypoglycemia was related to the BGL while leaving the PACU (odds ratio (OR) 0.37 [95% confidence interval (CI) 0.22 to 0.65]). The best cut-off value (12.95 mmol/L) was determined by fitting the ROC curve. CONCLUSIONS: If severe hyperglycemia develops during hysteroscopic surgery in individuals with 5% glucose as the mediator of uterine distention, the recommendation is to maintain blood glucose above 12.95 mmol/L when treated with insulin.

Study on the biological mechanism of urolithin a on nasopharyngeal carcinoma in vitro.

CONTEXT: Urolithin A (UroA) can inhibit the growth of many human cancer cells, but it has not be reported if UroA inhibits nasopharyngeal carcinoma (NPC) cells. OBJECTIVE: To explore the inhibitory effect of UroA on NPC and potential mechanism in vitro. MATERIALS AND METHODS: RNA-sequencing-based mechanistic prediction was conducted by comparing KEGG enrichment of 40 µM UroA-treated for 24 h with untreated CNE2 cells. The untreated cells were selected as control. After NPC cells were treated with 20-60 µM UroA, proliferation, migration and invasion of were measured by colony formation, wound healing and transwell experiments. Apoptosis, mitochondrial membrane potential (MMP), reactive oxygen species (ROS) were measured by flow cytometry, Hoechst 33342, Rhodamine 123, JC-1 staining and ROS assay methods, respectively. Gene and protein expression were measured by RT-qPCR and Western blotting assay. RESULTS: RNA-sequencing and KEGG enrichment revealed UroA mainly altered the ECM receptor interaction pathway. UroA inhibited cells proliferation, epithelial-mesenchymal-transition pathway, migration and invasion with IC50 values of 34.72 µM and 44.91 µM, induced apoptosis, MMP depolarization and increase ROS content at a concentration of 40 µM. UroA up-regulated E-cadherin, Bax/Bcl-2, c-caspase-3 and PARP proteins, while inhibiting COL4A1, MMP2, MMP9, N-cadherin, Vimentin and Snail proteins at 20-60 µM. Moreover, co-treatment of UroA (40 µM) and NAC (5 mM) could reverse the effect of UroA on apoptosis-related proteins. DISCUSSION AND CONCLUSIONS: RNA-sequencing technology based on bioinformatic analyses may be applicable for studiying the mechanism of drugs for tumour treatment.

Comparison of ultrasound-guided high-intensity focused ultrasound ablation and surgery for abdominal wall endometriosis.

BACKGROUND: Surgery constitutes the standard approach for abdominal wall endometriosis (AWE), but is invasive. High-intensity focused ultrasound (HIFU) ablation is effective and safe for the treatment of AWE, but no study has compared HIFU and surgery. OBJECTIVE: To report our experience about the benefits and adverse events of surgery compared to HIFU for the treatment of AWE. METHODS: This was a retrospective study of 54 consecutive Chinese women with AWE after cesarean section treated at the First Affiliated Hospital of Chongqing Medical University (China) between January 2012 and December 2014. The patients underwent surgery (n = 29) or HIFU (n = 25). The technical success rate, adverse events, and recurrence were assessed. RESULTS: The technical success rate was 100% in both groups. The complete remission rate was 92.0% (23/25) in the HIFU group, and 100% (29/29) in the surgery group. Numeric rating scale (NRS) scores after HIFU were significantly improved from 6.9 to 0.3.During the median follow-up period of 32 months (range, 19-46 months), the durations of pain relief were 29.7 ± 12.6 months and 25.0 ± 13.5 months in the surgery and HIFU groups, respectively (p = .337). Three patients (10.7%) experienced pain recurrence in the surgery group, and two (8.0%) in the HIFU group. Major adverse events occurred in four (13.8%) and one (4.0%) patients in the surgery and HIFU groups, respectively (p > .05). CONCLUSIONS: HIFU appears to be beneficial for the treatment of AWE, and may reduce adverse events. Compared with surgery, HIFU does not induce blood loss or tissue defects.

A Blockade of IGF Signaling Sensitizes Human Ovarian Cancer Cells to the Anthelmintic Niclosamide-Induced Anti-Proliferative and Anticancer Activities.

BACKGROUND/AIMS: Ovarian cancer is the most lethal gynecologic malignancy, and there is an unmet clinical need to develop new therapies. Although showing promising anticancer activity, Niclosamide may not be used as a monotherapy. We seek to investigate whether inhibiting IGF signaling potentiates Niclosamide's anticancer efficacy in human ovarian cancer cells. METHODS: Cell proliferation and migration are assessed. Cell cycle progression and apoptosis are analyzed by flow cytometry. Inhibition of IGF signaling is accomplished by adenovirus-mediated expression of siRNAs targeting IGF-1R. Cancer-associated pathways are assessed using pathway-specific reporters. Subcutaneous xenograft model is used to determine anticancer activity. RESULTS: We find that Niclosamide is highly effective on inhibiting cell proliferation, cell migration, and cell cycle progression, and inducing apoptosis in human ovarian cancer cells, possibly by targeting multiple signaling pathways involved in ELK1/SRF, AP-1, MYC/MAX and NFkB. Silencing IGF-1R exert a similar but weaker effect than that of Niclosamide's. However, silencing IGF-1R significantly sensitizes ovarian cancer cells to Niclosamide-induced anti-proliferative and anticancer activities both in vitro and in vivo. CONCLUSION: Niclosamide as a repurposed anticancer agent may be more efficacious when combined with agents that target other signaling pathways such as IGF signaling in the treatment of human cancers including ovarian cancer.

Radical-mediated divergent cyclization of benzamides toward perfluorinated or cyanated isoquinolinediones.

A simple and efficient copper-controlled divergent cyclization of benzamides, which leads to perfluorinated or cyanated isoquinolinediones, is developed. In the presence of AIBN, methacryloyl benzamides with perfluoroalkyl iodides undergo cascade radical addition/cyclization to afford perfluoroinated isoquinolinediones as the major product under metal-free conditions, whereas the use of CuI (10 mol%) is able to redirect the cyclization to yield isoquinolinediones bearing an α-cyano quaternary carbon center. The cyclization features controllable divergent synthesis and a broad substrate scope as well as highly practical reaction conditions, thereby making this strategy a highly attractive means to fluorinate or cyanate isoquinolinediones.

Synthesis of Perfluorinated Isoquinolinediones through Visible-Light-Induced Cyclization of Alkenes.

A novel visible-light-induced carboperfluoroalkylation of alkenes using perfluoroalkyl iodides and bromides as Rf sources, leading to isoquinoline-1,3-diones, was developed. This method offers rapid entry to perfluorinated isoquinoline-1,3(2H,4H)-diones from N-alkyl-N-methacryloyl benzamides under mild reaction conditions, allowing for the incorporation of a wide variety of perfluorinated groups such as CF3, C3F7, C4F9, C6F13, C8F17, C10F21, and CF2CO2Et.

Functional characteristics of reversibly immortalized hepatic progenitor cells derived from mouse embryonic liver.

BACKGROUND/AIMS: Liver is a vital organ and retains its regeneration capability throughout adulthood, which requires contributions from different cell populations, including liver precursors and intrahepatic stem cells. To overcome the mortality of hepatic progenitors (iHPs) in vitro, we aim to establish reversibly immortalized hepatic progenitor cells from mouse embryonic liver. METHODS AND RESULTS: Using retroviral system to stably express SV40 T antigen flanked with Cre/LoxP sites, we establish a repertoire of iHP clones with varied differentiation potential. The iHP cells maintain long-term proliferative activity and express varied levels of progenitor markers (Pou5f1/Oct4 and Dlk) and hepatocyte markers (AFP, Alb and ApoB). Five representative iHP clones express hepatic/pancreatic transcription factors HNF3α/Foxa1, HNF3ß/Foxa2, and HNF4α/MODY1. Dexamethasone is shown to promote the expression of hepatocyte markers AFP and TAT, along with ICG-uptake and glycogen storage functions in the iHP clones. Cre-mediated removal of SV40 T antigen reverses the proliferative activity of iHP cells. When iHP cells are subcutaneously implanted in athymic nude mice, no tumor formation is observed for up to 8 weeks. CONCLUSIONS: We demonstrate that the established iHP cells are stable, reversible, and non-tumorigenic hepatic progenitor-like cells, which should be valuable for studying liver organogenesis, metabolic regulations, and hepatic lineage-specific differentiation.

Nomograms for predicting overall survival and cancer-specific survival of endometrioid ovarian carcinoma: A retrospective cohort study from the SEER database.

OBJECTIVE: Endometrioid ovarian cancer (EnOC) accounts for approximately 10%-15% of epithelial ovarian cancer cases. There are no effective tools for predicting the prognosis of EnOC in clinical work. The aim of this study was to construct and validate a nomogram to predict overall survival and cancer-specific survival (CSS) in patients with EnOC. METHODS: Data regarding patients diagnosed with primary EnOC between 2004 and 2019 were obtained from the Surveillance, Epidemiology, and End Results (SEER) database. LASSO Cox regression and Cox regression analyses were performed to screen for prognostic factors, which were used to construct nomograms. In addition, we performed subgroup analyses of the prognostic value of chemotherapy and lymph node surgery. RESULTS: In total, 3957 patients with primary EnOC were included in the analysis: 2770 in a training cohort and 1187 in a validation cohort. Age, stage, grade, lymph node surgery, and race were significantly and independently correlated with overall survival and CSS. Nomograms were constructed to predict 3- and 5-year overall survival and CSS. Nomograms have good predictive ability and clinical practicability. Subgroup analysis showed that lymph node surgery improved the prognosis of patients with EnOC (P < 0.05) except for patients with grade III-IV and Stage I disease (overall survival P = 0.272, CSS P = 0.624). Chemotherapy did not improve survival time in most patients (P > 0.05) except for patients with grade I-II and Stage II-IV disease (overall survival P = 0.008, CSS P = 0.046). CONCLUSION: We constructed predictive nomograms and a risk classification system to evaluate overall survival and CSS in EnOC patients. For most patients with EnOC, chemotherapy did not improve the prognosis. In contrast to chemotherapy, lymph node surgery improved prognosis in most patients with EnOC.

Synthesis of Planar Chiral Compounds Containing α-Amino Phosphonates for Antiplant Virus Applications against Potato Virus Y.

An unprecedented study of the application of planar chiral compounds in antiviral pesticide development is reported. A class of multifunctional planar chiral ferrocene derivatives bearing α-amino phosphonate moieties was synthesized. These compounds, exhibiting superior optical purities, were subsequently subjected to antiviral evaluations against the notable plant pathogen potato virus Y (PVY). The influence of the absolute configurations of the planar chiral compounds on their antiviral bioactivities was significant. A number of these enantiomerically enriched planar chiral molecules demonstrated superior anti-PVY activities. Specifically, compound (Sp, R)-9n displayed extraordinary curative activities against PVY, with a 50% maximal effective concentration (EC50) of 216.11 µg/mL, surpassing the efficacy of ningnanmycin (NNM, 272.74 µg/mL). The protective activities of compound (Sp, R)-9n had an EC50 value of 152.78 µg/mL, which was better than that of NNM (413.22 µg/mL). The molecular docking and defense enzyme activity tests were carried out using the planar chiral molecules bearing different absolute configurations to investigate the mechanism of their antiviral activities against PVY. (Sp, R)-9n, (Sp, R)-9o, and NMM all showed stronger affinities to the PVY-CP than the (Rp, S)-9n. Investigations into the mechanisms revealed that the planar chiral configurations of the compounds played pivotal roles in the interactions between the PVY-CP molecules and could augment the activities of the defense enzymes. This study contributes substantial insights into the role of planar chirality in defending plants against viral infections.

Recent Achievements in Antiviral Agent Development for Plant Protection.

Plant virus disease is the second most prevalent plant diseases and can cause extensive loss in global agricultural economy. Extensive work has been carried out on the development of novel antiplant virus agents for preventing and treating plant virus diseases. In this review, we summarize the achievements of the research and development of new antiviral agents in the recent five years and provide our own perspective on the future development in this highly active research field.

Development of axially chiral urazole scaffolds for antiplant virus applications against potato virus Y.

BACKGROUND: Potato virus Y (PVY) was first discovered by Smith in 1931 and is currently ranked as the fifth most significant plant virus. It can cause severe damage to plants from the family Solanaceae, which results in billions of dollars of economic loss worldwide every year. To discover new antiviral drugs, a class of multifunctional urazole derivatives bearing a stereogenic CN axis were synthesized with excellent optical purities for antiviral evaluations against PVY. RESULTS: The absolute configurations of the axially chiral compounds exhibited obvious distinctions in antiviral bioactivities, with several of these enantio-enriched axially chiral molecules showing excellent anti-PVY activities. In particular, compound (R)-9f exhibited remarkable curative activities against PVY with a 50% maximal effective concentration (EC50 ) of 224.9 µg mL-1 , which was better than that of ningnanmycin (NNM), which had an EC50 of 234.0 µg mL-1 . And the EC50 value of the protective activities of compound (R)-9f was 462.2 µg mL-1 , which was comparable to that of NNM (442.0 µg mL-1 ). The mechanisms of two enantiomer of the axially chiral compounds 9f were studied by both molecule docking and defensive enzyme activity tests. CONCLUSION: Mechanistic studies demonstrated that the axially chiral configurations of the compounds played significant roles in the molecule PVY-CP (PVY Coat Protein) interactions and could enhance the activities of the defense enzymes. The (S)-9f showed only one carbon-hydrogen bond and one π-cation interaction between the chiral molecule and the PVY-CP amino acid sites. In contrast, the (R)-enantiomer of 9f exhibited three hydrogen bonding interactions between the carbonyl groups and the PVY-CP active sites of ARG157 and GLN158. The current study provides significant information on the roles that axial chiralities play in plant protection against viruses, which will facilitate the development of novel green pesticides bearing axial chiralities with excellent optical purities. © 2023 Society of Chemical Industry.

Effect of antibiotic monensin on cell proliferation and IGF1R signaling pathway in human colorectal cancer cells.

BACKGROUND/AIMS: Colorectal cancer is the third leading cause of death in patients with cancers in America. Monensin has represented anti-cancer effect on various human cancer cells. We seek to investigate the effect of monensin on proliferation of human colorectal cancer cells and explore whether IGF1R signaling pathway is involved in anti-cancer mechanism of monensin. METHODS: Cell proliferation and migration were assessed by crystal violet staining and cell wounding assay respectively. Cell apoptosis was analyzed by Hoechst 33258 staining and flow cytometry. Cell cycle progression was detected with the use of flow cytometry. Cancer-associated pathways were assessed with the use of pathway-specific reporters. Gene expression was detected by touchdown-quantitative real-time PCR. Inhibition of IGF1R was tested by immunofluorescence staining. Inhibition of IGF1R signaling was accomplished by adenovirus-mediated expression of IGF1. RESULTS: We found that monensin not only effectively inhibited cell proliferation, cell migration as well as cell cycle progression, but also induced apoptosis and G1 arrest in human colorectal cancer cells. Monensin was shown to target multiple cancer-related signaling pathways such as Elk1, AP1, as well as Myc/max, and suppressed IGF1R expression via increasing IGF1 in colorectal cancer cells. CONCLUSION: Monensin could suppressed IGF1R expression via increasing IGF1 in colorectal cancer cells. It has the potential to be repurposed as an anti-colorectal cancer agent, but further studies are still required to investigate the detailed mechanisms of monensin underlying its anti-cancer motion.Key MessagesMonensin inhibits the cell proliferation and the migration, induces apoptosis and inhibits cell cycle progression in human colorectal cancer cells.Monensin may exert anti-cancer activity by targeting multiple signaling pathways, including the IGF1R signaling pathway.Monensin has the potential to be repurposed as an anti-colorectal cancer agent.

Correction: Adenovirus-Mediated Efficient Gene Transfer into Cultured Three-Dimensional Organoids.

[This corrects the article DOI: 10.1371/journal.pone.0093608.].

MicroRNA-764-3p regulates 17ß-estradiol synthesis of mouse ovarian granulosa cells by targeting steroidogenic factor-1.

Previous studies have reported that microRNA-764-3p (miR-764-3p) is one of the most up-regulated microRNAs (miRNAs) in TGF-ß1-stimulated mouse ovarian granulosa cells. However, little is known about the roles and mechanisms of miR-764-3p in granulosa cell function during follicular development. In this study, we found that overexpression of miR-764-3p inhibited 17ß-estradiol (E2) synthesis of granulosa cells through directly targeting steroidogenic factor-1 (SF-1). MiR-764-3p inhibited SF-1 by affecting its messenger RNA (mRNA) stability, which subsequently suppressed the expression levels of Cyp19a1 gene (aromatase, a downstream target of SF-1). In addition, SF-1 was involved in regulation of miR-764-3p-mediated Cyp19a1 expression in granulosa cells which contributed, at least partially, to the effects of miR-764-3p on granulosa cell E2 release. These results suggest that miR-764-3p functions to decrease steroidogenesis by targeting SF-1, at least in part, through inactivation of Cyp19a1. Taken together, our data provide mechanistic insights into the roles of miR-764-3p on E2 synthesis. Understanding of potential miRNAs affecting estrogen synthesis will help to diagnose and treat steroid-related diseases.

Aerobic oxidative cyclization of benzamides via meta-selective C-H tert-alkylation: rapid entry to 7-alkylated isoquinolinediones.

A novel copper-catalyzed aerobic oxidative cyclization of benzamides via meta-selective C-H tert-alkylation using AIBN and analogues as radical precursors was described. This strategy provides an elusive and rapid means to 7-tert-alkylated isoquinolinediones, as well as the construction of tertiary alkyl-aryl C(sp(3))-C(sp(2)) bonds with positional selectivity.

[Analysis of two-dimension gel electrophoresis of human large cell lung cancer cell lines with different metastasis potentials].

BACKGROUND: Metastasis is not only the malignant characteristics of lung can- cer, but also the chief cause of failure to cure and high mortality of lung cancer. To better explore and understand the mechanism of lung cancer metastasis and to search for potential markers for early diagnosing and reversing lung cancer metastasis, differential proteomic analysis is conducted in two human large cell lung cancer cell lines with high metastasis potentials (L9981) and low metastasis potentials (NL9980) by two-dimension gel electrophoresis (2-DE). METHODS: The total proteins of the two cell lines were separated by immobilized pH gradient (IPG)-based 2-DE. The differentially expressed proteins of the two cell lines were analyzed using image analysis software. RESULTS: A high resolution and reproducible 2-DE image was successfully obtained. Average deviations for protein position in IEF direction were (0.858±0.076)mm and (1.514±0.127)mm in SDS-PAGE direction. The relative standard deviation for protein volume was (12.06±0.580)% in L9981 and (12.22±0.640)% in NL9980. The average total number of protein spots was 902±169 in L9981 cells and 941±173 in NL9980 cells in three repeated experiments. Image analysis of siliver-stained 2-DE image revealed that 4 protein spots had significant differential expressions in L9981 and NL9980 (student's t-test, P < 0.05). Fifteen protein spots were only detected in L9981, and 27 protein spots were only detected in NL9980. CONCLUSIONS: The results in this study suggest that an obviously differential proteomic expression exists between the human high- and low-metastatic large cell lung cancer cell lines. It will be helpful to further understand the molecular mechanisms of lung cancer invasion and metastasis, and provide new experimental evidence for searching metastatic-related molecule of lung cancer.

Canonical Wnt signaling acts synergistically on BMP9-induced osteo/odontoblastic differentiation of stem cells of dental apical papilla (SCAPs).

Dental pulp/dentin regeneration using dental stem cells combined with odontogenic factors may offer great promise to treat and/or prevent premature tooth loss. Here, we investigate if BMP9 and Wnt/ß-catenin act synergistically on odontogenic differentiation. Using the immortalized SCAPs (iSCAPs) isolated from mouse apical papilla tissue, we demonstrate that Wnt3A effectively induces early osteogenic marker alkaline phosphatase (ALP) in iSCAPs, which is reduced by ß-catenin knockdown. While Wnt3A and BMP9 enhance each other's ability to induce ALP activity in iSCAPs, silencing ß-catenin significantly diminishes BMP9-induced osteo/odontogenic differentiation. Furthermore, silencing ß-catenin reduces BMP9-induced expression of osteocalcin and osteopontin and in vitro matrix mineralization of iSCAPs. In vivo stem cell implantation assay reveals that while BMP9-transduced iSCAPs induce robust ectopic bone formation, iSCAPs stimulated with both BMP9 and Wnt3A exhibit more mature and highly mineralized trabecular bone formation. However, knockdown of ß-catenin in iSCAPs significantly diminishes BMP9 or BMP9/Wnt3A-induced ectopic bone formation in vivo. Thus, our results strongly suggest that ß-catenin may play an important role in BMP9-induced osteo/ondontogenic signaling and that BMP9 and Wnt3A may act synergistically to induce osteo/odontoblastic differentiation of iSCAPs. It's conceivable that BMP9 and/or Wnt3A may be explored as efficacious biofactors for odontogenic regeneration and tooth engineering.

The Anthelmintic Drug Niclosamide Inhibits the Proliferative Activity of Human Osteosarcoma Cells by Targeting Multiple Signal Pathways.

Osteosarcoma (OS) is the most common primary malignant tumor of bone with a high propensity for lung metastasis. Despite significant advances in surgical techniques and chemotherapeutic regimens over the past few decades, there has been minimal improvement in OS patient survival. There is an urgent need to identify novel antitumor agents to treat human OS. Repurposing the clinically-used drugs represents a rapid and effective approach to the development of new anticancer agents. The anthelmintic drug niclosamide has recently been identified as a potential anticancer agent in human cancers. Here, we investigate if niclosamide can be developed as an anti-OS drug. We find that niclosamide can effectively inhibit OS cell proliferation and survival at low micromolar concentrations. Cell migration and wounding closure are significantly inhibited by niclosamide. Niclosamide induces cell apoptosis and inhibits cell cycle progression in OS cells. Analysis of niclosamide's effect on 11 cancer-related signal pathway reporters reveals that three of them, the E2F1, AP1, and c-Myc-responsive reporters, are significantly inhibited. To a lesser extent, the HIF1α, TCF/LEF, CREB, NFκB, Smad/TGFß, and Rbpj/Notch pathway reporters are also inhibited, while the NFAT and Wnt/ß-catenin reporters are not significantly affected by niclosamide treatment. We demonstrate that the expression of c-Fos, c-Jun. E2F1, and c-Myc in OS cells is effectively inhibited by niclosamide. Furthermore, niclosamide is shown to effectively inhibit tumor growth in a mouse xenograft tumor model of human osteosarcoma cells. Taken together, these results strongly suggest that niclosamide may exert its anticancer activity in OS cells by targeting multiple signaling pathways. Future investigations should be directed to exploring the antitumor activity in clinically relevant OS models and ultimately in clinical trials.

Antibiotic monensin synergizes with EGFR inhibitors and oxaliplatin to suppress the proliferation of human ovarian cancer cells.

Ovarian cancer is the most lethal gynecologic malignancy with an overall cure rate of merely 30%. Most patients experience recurrence within 12-24 months of cure and die of progressively chemotherapy-resistant disease. Thus, more effective anti-ovarian cancer therapies are needed. Here, we investigate the possibility of repurposing antibiotic monensin as an anti-ovarian cancer agent. We demonstrate that monensin effectively inhibits cell proliferation, migration and cell cycle progression, and induces apoptosis of human ovarian cancer cells. Monensin suppresses multiple cancer-related pathways including Elk1/SRF, AP1, NFκB and STAT, and reduces EGFR expression in ovarian cancer cells. Monensin acts synergistically with EGFR inhibitors and oxaliplatin to inhibit cell proliferation and induce apoptosis of ovarian cancer cells. Xenograft studies confirm that monensin effectively inhibits tumor growth by suppressing cell proliferation through targeting EGFR signaling. Our results suggest monensin may be repurposed as an anti-ovarian cancer agent although further preclinical and clinical studies are needed.

TqPCR: A Touchdown qPCR Assay with Significantly Improved Detection Sensitivity and Amplification Efficiency of SYBR Green qPCR.

The advent of fluorescence-based quantitative real-time PCR (qPCR) has revolutionized the quantification of gene expression analysis in many fields, including life sciences, agriculture, forensic science, molecular diagnostics, and medicine. While SYBR Green-based qPCR is the most commonly-used platform due to its inexpensive nature and robust chemistry, quantifying the expression of genes with low abundance or RNA samples extracted from highly restricted or limited sources can be challenging because the detection sensitivity of SYBR Green-based qPCR is limited. Here, we develop a novel and effective touchdown qPCR (TqPCR) protocol by incorporating a 4-cycle touchdown stage prior to the quantification amplification stage. Using the same cDNA templates, we find that TqPCR can reduce the average Cq values for Gapdh, Rps13, and Hprt1 reference genes by 4.45, 5.47, and 4.94 cycles, respectively, when compared with conventional qPCR; the overall average Cq value reduction for the three reference genes together is 4.95. We further find that TqPCR can improve PCR amplification efficiency and thus increase detection sensitivity. When the quantification of Wnt3A-induced target gene expression in mesenchymal stem cells is analyzed, we find that, while both conventional qPCR and TqPCR can detect the up-regulation of the relatively abundant target Axin2, only TqPCR can detect the up-regulation of the lowly-expressed targets Oct4 and Gbx2. Finally, we demonstrate that the MRQ2 and MRQ3 primer pairs derived from mouse reference gene Tbp can be used to validate the RNA/cDNA integrity of qPCR samples. Taken together, our results strongly suggest that TqPCR may increase detection sensitivity and PCR amplification efficiency. Overall, TqPCR should be advantageous over conventional qPCR in expression quantification, especially when the transcripts of interest are lowly expressed, and/or the availability of total RNA is highly restricted or limited.