Role of L-Arginine on the Expression of Coagulation Factor VIII Gene.

Objective: To explore the key sites in which L-arginine affects the expression of human coagulation factor VIII gene, and to create new drug targets for the treatment of hemophilia. Methods: A total of 5 human FVIII genes (A1, A2, A3, C1 and C2) with B domain deletion were transfected into human umbilical vein endothelial cells (HUVECs) as promoters. Run-on assay and ELISA analysis were performed to observe the driving effect of each domain gene on chloramphenicol acetyl transferase (CAT) gene transcription and expression, and the effect of L-arginine on each promoter. Results: In co-culture with L-arginine, transcriptional expression of the CAT gene was not detected in the PCAT3-Basic group (negative control without promoters), PA3-CAT3-Enhancer group or PC1-CAT3-Enhancer group. The transcriptional expression of CAT gene in the PCAT3-Control group (positive control with promoters) and PA1-CAT3-Enhancer group was unchanged compared with the non-L-arginine intervention, while the transcriptional expression of CAT gene in the PA2-CAT3-Enhancer group was significantly enhanced. Conclusions: A1 and A2 domain genes had promoter function and could initiate the transcription and expression of CAT gene, but A3, C1 and C2 domain genes could not. Moreover, L-arginine can significantly enhance transcription and expression of human coagulation factor VIII via A2 domain.

[The neural basis underlying primary dysmenorrhea: evidence from neuroimaging and animal model studies].

Primary dysmenorrhea (PDM), cyclic menstrual pain in the absence of pelvic anomalies, is characterized by acute and chronic gynecological pain disorders in childbearing age women. PDM strongly affects the quality of life of patients and leads to economic losses. PDM generally do not receive radical treatment and often develop into other chronic pain disorders later in life. The clinical treatment status of PDM, the epidemiology of PDM and chronic pain comorbidities, and the abnormal physiological and psychological characteristics of patients with PDM suggest that PDM not only is related to the inflammation around the uterus, but also may be related to the abnormal pain processing and regulation function of patients' central system. Therefore, exploring the brain neural mechanism of PDM is indispensable and important to understand the pathological mechanism of PDM, and is also a hotspot of brain science research in recent years, which will bring new inspiration to explore the target of PDM intervention. Based on the progress of the neural mechanism of PDM, this paper systematically summarizes the evidence from neuroimaging and animal model studies.

Investigation on abnormal gene loci of a Chinese pedigree with hereditary combined deficiency of blood coagulation factor XI, XII, and protein S.

OBJECTIVE: In order to clarify the interaction mechanism, the phenotype and abnormal gene loci of FXI, FXII, and PS were investigated in this study. METHODS: Chinese pedigree with hereditary combined deficiency of coagulation factor (F) XI, FXII, and PS was enrolled in our study. Activated partial thromboplastin time (APTT), partial thromboplastin time (PT), FXI:C, FXII:C, and protein S (PS):C were determined using the one-stage coagulation method. FXI:antigen (Ag), FXII:Ag, and PS:Ag were detected using enzyme-linked immunosorbent assay (ELISA). Exons and introns of the FXI, FXII, and PS genes were amplified by polymerase chain reaction (PCR), and gene sequencing results were analyzed using Chromas software. RESULTS: A deletion of two bases located in introns A-149 and-150 within the FXI gene of the proband, his father, wife, and both sons. A missense variant in exon 14 (GGT â†’ AGT, Gly542Ser) within FXII of the proband, his parents, and both sons. Four variants in exon 4 within the PS gene of all members of the pedigree: GTT â†’ GTG (Val46Val), CGC â†’ CTC (Arg49Leu), CGT â†’ CAT (Arg60His), and CAG â†’ TAG (Gln61stop). CONCLUSIONS: None of the pedigree members showed a tendency for bleeding or thrombosis. Therefore, we speculated that the lack of coagulation factors counteracted the lack of PS, restoring the balance between the coagulation and anticoagulation systems. Another possible explanation is that these defects individually have only partial penetrance.

Preparation of Highly Dispersed WO3 Nanoparticles on Carbon Nanotubes and Application as Visible Photocatalyst.

Tungsten oxide nanoparticles with high dispersion supported on carbon nanotube (CNT) templates were fabricated by the liquid phase method. Given the isolation effects of the network from CNT bundles, the nano-size H2WO4 and WO3 can be obtained. The photodegradation ability of the WO3/CNTs was evaluated by methylene blue (MB). The degradation rate of MB can reach 94.7% for 30 min, which is superior to that of pure WO3 at 73.1% for 30 min. Furthermore, the degradation rate of the catalyst can reach 83.7% after recycling for five times, thus displaying the excellent stability of the photocatalyst. These results may be attributed to the highly dispersed WO3 nanoparticles and the suppression of electron-hole recombination by CNT templates. This study proves that WO3/CNT photocatalysts have potential applications in environmental and other related fields.

[Testicular injection of lipopolysaccharide: An effective method for establishing the mouse model of orchitis].

OBJECTIVE: To search for a method of establishing a reliable mouse model of orchitis and investigate the association of orchitis with the activation of the inflammasome. METHODS: We equally randomized 40 adult male KM mice into groups A (sham operation), B (intraperitoneal injection of lipopolysaccharide ï¼»LPSï¼½), C (unilateral testicular injection of glacial acetic acid ï¼»GAAï¼½), and D (unilateral testicular injection of LPS). At 3 weeks after modeling, we measured the sperm concentration and percentage of progressively motile sperm (PMS) in the epididymis by computer-assisted semen analysis, observed the pathological changes in the testis tissue by HE staining, and determined the expressions of the Caspase-1 and interleukin (IL)-1ß proteins by Western blot. RESULTS: The sperm concentration in the epididymis was significantly decreased in groups B (ï¼»25.74 ± 3.19ï¼½ ×106/ml), C (ï¼»17.16 ± 4.41ï¼½ ×106/ml) and D (ï¼»16.92 ± 7.13ï¼½ ×106/ml) as compared with that in group A (ï¼»28.20 ± 1.63ï¼½ ×106/ml) (all P < 0.05), even more significantly in B than in C and D (P < 0.01), and so was PMS in groups B (ï¼»29.57 ± 2.16ï¼½%), C (ï¼»18.10 ± 2.38ï¼½%) and D (ï¼»7.34 ± 1.63ï¼½%) in comparison with group A (ï¼»59.34 ± 1.10ï¼½%) (P < 0.01), even more significantly in B and C than in D (P < 0.01). Light microscopy revealed different degrees of pathological changes in the testis tissue, most significant in group D, followed by C and B. Both the expressions of Caspase-1 and IL-1ß were remarkably up-regulated in groups B, C and D compared with those in group A (P < 0.01), even more markedly in D than in B and C (P < 0.05). CONCLUSIONS: Unilateral testicular injection of LPS is a more efficient method than either unilateral testicular injection of GAA or intraperitoneal injection of LPS for establishing the mouse model of orchitis. Orchitis may be pathologically associated with the activation of the NLRP3 inflammasome.

[Establishment of animal models of orchitis: Advances in studies].

Male infertility is becoming a concern of the world. Studies show that testicular inflammation is closely related to male infertility, which often manifests itself in low sperm count and motility and even the loss of fertility. In recent years, testicular inflammation-induced male infertility is arousing more and more attention, which adds to the significance of its study. It is imperative to establish stable and reliable animal models for further research on orchitis-induced spermatogenetic dysfunction and the mechanisms of spermatogenesis. This article presents an overview of recent studies on the establishment of animal models of orchitis to provide some reference for researchers in the relevant fields.

Omalizumab for the treatment of chronic spontaneous urticaria: A meta-analysis of randomized clinical trials.

BACKGROUND: Chronic spontaneous urticaria (CSU) is defined by itchy hives, angioedema, or both for at least 6 weeks. Omalizumab, an anti-IgE antibody that affects mast cell and basophil function, is a promising new treatment option. As of now, however, the efficacy and safety of different doses of omalizumab used in clinical trials for CSU have not been systematically analyzed and summarized. OBJECTIVE: We sought to assess the efficacy and safety of different doses of omalizumab for the treatment of CSU in a meta-analysis of clinical trial results. METHODS: Suitable trials were identified by searching PubMed, Medline, Embase, and Web of Science databases and with the help of omalizumab's manufacturers. Only double-blind, randomized, placebo-controlled studies with omalizumab-treated versus placebo-treated patients with CSU were included in this analysis. RESULTS: We identified 7 randomized, placebo-controlled studies with 1312 patients with CSU. Patients treated with omalizumab (75-600 mg every 4 weeks) had significantly reduced weekly itch and weekly wheal scores compared with the placebo group. Omalizumab's effects were dose dependent, with the strongest reduction in weekly itch and weekly wheal scores observed with 300 mg. Rates of complete response were significantly higher in the omalizumab group (relative risk, 4.55; P < .00001) and dose dependent, with the highest rates in the 300-mg group. Rates of patients with adverse events were similar in the omalizumab and placebo groups. CONCLUSION: This meta-analysis provides high-quality evidence for the efficacy and safety of omalizumab in patients with CSU and for treating these patients with 300 mg of omalizumab every 4 weeks.

[A sketch of the overlap in the neural circuitry underlying psychological- and physical-pain].

From the phenomenological point of view, pain can be classified into psychological-pain and physical-pain. Emerging evidence has shown that the psychological- and physical-pain recruit overlapping neural activity in regions associated with the affective component of pain, and share some common pain circuits, e.g., the dorsal anterior cingulate cortex (dACC) and the anterior insula (AI) play important roles in both psychological- and physical-pain. Therefore, understanding the way in which psychological- and physical-pain demonstrate either similarity or discrepancy may provide new insights into the relationship between the two types of experiences and potential targets for treating psychological suffering. This review summarizes research progress that has been obtained through experiments conducted in human and nonhuman animals to discuss the similarity, discrepancy and interaction between psychological- and physical-pain. The important next steps, e.g., uncovering the mechanisms underlying the overlap of psychological- and physical-pain; and whether chronic psychological-pain shapes brain plasticity as physical-pain does, are also discussed.

Oridonin stabilizes retinoic acid receptor alpha through ROS-activated NF-κB signaling.

BACKGROUND: Retinoic acid receptor alpha (RARα) plays an essential role in the regulation of many biological processes, such as hematopoietic cell differentiation, while abnormal RARα function contributes to the pathogenesis of certain diseases including cancers, especially acute promyelocytic leukemia (APL). Recently, oridonin, a natural diterpenoid isolated from Rabdosia rubescens, was demonstrated to regulate RARα by increasing its protein level. However, the underlying molecular mechanism for this action has not been fully elucidated. METHODS: In the APL cell line, NB4, the effect of oridonin on RARα protein was analyzed by western blot and real-time quantitative RT-PCR analyses. Flow cytometry was performed to detect intracellular levels of reactive oxygen species (ROS). The association between nuclear factor-kappa B (NF-κB) signaling and the effect of oridonin was assessed using specific inhibitors, shRNA gene knockdown, and immunofluorescence assays. In addition, primary leukemia cells were treated with oridonin and analyzed by western blot in this study. RESULTS: RARα possesses transcriptional activity in the presence of its ligand, all-trans retinoic acid (ATRA). Oridonin remarkably stabilized the RARα protein, which retained transcriptional activity. Oridonin also moderately increased intracellular ROS levels, while pretreatment with the ROS scavenger, N-acetyl-l-cysteine (NAC), dramatically abrogated RARα stabilization by oridonin. More intriguingly, direct exposure to low concentrations of H2O2 also increased RARα protein but not mRNA levels, suggesting a role for ROS in oridonin stabilization of RARα protein. Further investigations showed that NAC antagonized oridonin-induced activation of NF-κB signaling, while the NF-κB signaling inhibitor, Bay 11-7082, effectively blocked the oridonin increase in RARα protein levels. In line with this, over-expression of IκΒα (A32/36), a super-repressor form of IκΒα, or NF-κB-p65 knockdown inhibited oridonin or H2O2-induced RARα stability. Finally, tumor necrosis factor alpha (TNFα), a classical activator of NF-κB signaling, modulated the stability of RARα protein. CONCLUSIONS: Oridonin stabilizes RARα protein by increasing cellular ROS levels, which causes activation of the NF-κB signaling pathway.

[Platelet-derived growth factor-BB induces phenotypic transformation of corpus cavernosum smooth muscle cells in SD rats].

OBJECTIVE: To evaluate the effect of the platelet-derived growth factor-BB (PDGF-BB) on the phenotypic transformation of corpus cavernosum smooth muscle cells (CCSMC) in SD rats. METHODS: CCSMCs were primarily cultured in the modified tissue sticking medium and subjected to immunofluorescence assay. The cells were divided into a blank control and four PDGF-BB groups, the latter exposed to 5, 10, 20, and 40 ng/ml of PDGF-BB, respectively, for 24 hours, and the cells in the 20 ng/ml PDGF-BB group treated for 24, 48, and 72 hours. The the relative expressions of α-SMA, SMMHC, calponin, and OPN mRNA were determined by real-time fluorescence quantitative RT-PCR (qRT-PCR). RESULTS: The α-SMA positive rate of the CCSMCs was over 95%. Compared with the blank control group, the expression levels of α-SMA, SMMHC, and calponin mRNA were significantly decreased (P < 0.05) while that of OPN mRNA remarkably increased (P < 0.05) in the PDGF-BB groups. The 20 ng/ml PDGF-BB group also showed significantly downregulated expressions of α-SMA, SMMHC, and calponin mRNA (P < 0.05) and upregulated expression of OPN mRNA (P < 0.05) at 24, 48, and 72 hours. CONCLUSION: PDGF-BB can induce the transformation of the phenotype of CCSMCs in SD rats from the contractile to the synthetic type.

Calcium Signaling Regulated by Cellular Membrane Systems and Calcium Homeostasis Perturbed in Alzheimer's Disease.

Although anything that changes spatiotemporally could be a signal, cells, particularly neurons, precisely manipulate calcium ion (Ca2+) to transmit information. Ca2+ homeostasis is indispensable for neuronal functions and survival. The cytosolic Ca2+ concentration ([Ca2+]CYT) is regulated by channels, pumps, and exchangers on cellular membrane systems. Under physiological conditions, both endoplasmic reticulum (ER) and mitochondria function as intracellular Ca2+ buffers. Furthermore, efficient and effective Ca2+ flux is observed at the ER-mitochondria membrane contact site (ERMCS), an intracellular membrane juxtaposition, where Ca2+ is released from the ER followed by mitochondrial Ca2+ uptake in sequence. Hence, the ER intraluminal Ca2+ concentration ([Ca2+]ER), the mitochondrial matrix Ca2+ concentration ([Ca2+]MT), and the [Ca2+]CYT are related to each other. Ca2+ signaling dysregulation and Ca2+ dyshomeostasis are associated with Alzheimer's disease (AD), an irreversible neurodegenerative disease. The present review summarizes the cellular and molecular mechanism underlying Ca2+ signaling regulation and Ca2+ homeostasis maintenance at ER and mitochondria levels, focusing on AD. Integrating the amyloid hypothesis and the calcium hypothesis of AD may further our understanding of pathogenesis in neurodegeneration, provide therapeutic targets for chronic neurodegenerative disease in the central nervous system.

Role of Ca2+, Calnexin and Calreticulin in Platelet from Adult Patients with Chronic Immune Thrombocytopenic Purpura.

BACKGROUND: Adult chronic immune thrombocytopenia (chronic ITP) is a common autoimmune hemorrhagic disease characterized by decreased platelet production and increased platelet destruction, leading to thrombocytopenia. In this study, Ca2+, calnexin (CNX) and calreticulin (CRT) within platelets from adult patients with chronic ITP were investigated. METHODS: Platelets were isolated from blood specimen collected from 20 adult patients with chronic ITP and 20 healthy volunteers. Ca2+, CNX and CRT were determined by flow cytometry, and the results were analyzed with EXPO32 ADC software. RESULTS: Flow cytometry showed the expressions of Ca2+ (74.19±19.40% vs 22.79±10.47%) was elevated (P<0.05). However, CNX (15.10±7.32% vs 41.79±14.45%) and CRT (25.11±12.66% vs 38.58±12.02%) were decreased markedly in platelets from adult patients with chronic ITP (P<0.05 compared with healthy volunteers). CONCLUSION: Based on enhanced expression of Ca2+ and attenuated expression of CNX and CRT in patients with chronic ITP, Ca2+ concentration and its associated down-regulated proteins may be important regulatory signals in the pathogenesis of chronic ITP.

Circular RNA hsa_circ_0072309 promotes tumorigenesis and invasion by regulating the miR-607/FTO axis in non-small cell lung carcinoma.

Emerging evidence has demonstrated that circular RNAs (circRNAs) are abnormally expressed in non-small cell lung carcinoma (NSCLC). However, the contributions of circRNAs to the tumorigenesis of lung adenocarcinoma (LUAD), one of the subtypes of NSCLC, remain unclear. Based on a microarray assay, we found that hsa_circ_0072309 was significantly upregulated in NSCLC compared with matched normal samples. Moreover, functional experiments demonstrated that hsa_circ_0072309 promotes the proliferation, migration, and invasion of NSCLC cells. In vitro precipitation of circRNAs, luciferase reporter assays, and biotin-coupled microRNA capture assays were carried out to investigate the mechanisms by which hsa_circ_0072309 regulates NSCLC. Through the above work, we found that hsa_circ_0072309 interacted with miR-607 via its miRNA response element to upregulate the expression of FTO, an m6A demethylase and downstream target of miR-607, thus promoting tumorigenesis of NSCLC. In total, our findings indicated the oncogenic role of hsa_circ_0072309 in NSCLC and provide a potential target for treatment.

Apoptosis in platelets from adult patients with chronic idiopathic thrombocytopenic purpura.

Adult chronic idiopathic thrombocytopenic purpura (cITP) is a chronic and usually life-long haemorrhagic disorder in which enhanced platelet destruction and weakened platelet production lead to thrombocytopenia. Platelets were isolated from blood samples collected from 40 adult patients with cITP and 40 healthy volunteers. Mitochondrial membrane potential (ΔΨm) and plasma membrane phosphatidylserine externalization were determined by flow cytometry, and activation of caspase-3 and expressions of Bax, Bak and Bcl-xL were analysed by western blotting. Flow cytometry showed increased mitochondrial depolarization and lower ΔΨm in platelets from adult patients with cITP. In addition, plasma membrane phosphatidylserine externalization was observed on platelets from adult patients with cITP, but rarely from healthy volunteers. Western blot analysis of platelet proteins revealed that, in adult cITP patients, caspase-3 was activated, which cleaved gelsolin and to release a 47-kDa fragment. Moreover, the expressions of Bax and Bak were elevated, and Bcl-xL was decreased markedly in platelets from adult patients with cITP. Our findings reveal, based on loss of mitochondrial membrane potential (Δψm), phosphatidylserine exposure, caspase-3 activation, enhanced expression of Bax and Bak, and attenuated expression of Bcl-xL, that platelet death in the pathogenesis of thrombocytopenia in chronic ITP in adults is apoptotic.

The diagnostic profile of rare acute myelomegakaryoblastic leukemia.

Acute myelomagakaryocytic leukemia is a diagnostic and therapeutic challenge owing to its heterogeneity and overlapping features with other types of acute leukemia. In order to build a diagnostic profile, we analyzed the biological, clinical and hematologic characteristics of acute myelomagakaryocytic leukemia. We found that, in three patients diagnosed with acute myelomagakaryocytic leukemia, there were two types of leukemia cells. One type was myeloblastic with positive peroxidase (POX) stainig and the expression of antigens CD13 and CD33. The other type was megakaryoblastic with negative POX staining and the expression of antigens CD36, CD41, CD42a and CD61. Three patients displayed the same cytogenetic abnormality, a (9: 22) translocation. Among the three patients with RT-PCR, two patients displayed BCR-ABL fusion gene amplification and one patient showed a previously undescribed OTT-MAL fusion gene amplification.

Antisense oligodeoxynucleotide against tissue factor inhibits human umbilical vein endothelial cells injury induced by anoxia-reoxygenation.

AIMS: The role of antisense oligodeoxynucleotide against tissue factor (aODN/TF) in cultured human umbilical vein endothelial cells (HUVECs) subjected to anoxia-reoxygenation (A/R) was investigated. METHODS: HUVECs were divided randomly into control group, A/R group, aODN/TF+A/R group, sense oligodeoxynucleotide (sODN/TF) + A/R group and mismatched oligodeoxynucleotide (mODN/TF) + A/R group, in the latter 3 groups, HUVECs were transfected with aODN/TF, sODN/TF and mODN/TF respectively. HUVECs in all A/R groups underwent 3 hrs of anoxia and followed by 2 hrs of reoxygenation. In order to investigate the potential mechanisms of how increased TF may contribute to A/R injury in HUVECs, another set of HUVECs were incubated with human recombinant active site blocked factor VII (FVIIai) during A/R. RESULTS: After A/R, TF expression at both mRNA and protein level was increased, furthermore, cell viability and the concentrations of SOD, GSH-PX and NO were declined, while LDH, MDA and ET-1 were overproduced (P<0.05 to 0.001 versus control group). In HUVECs of aODN/TF+A/R group, however, TF expression was inhibited, while the declined cell viability and the concentrations of SOD, GSH-PX, NO as well as the enhanced LDH, MDA and ET-1 levels occurred during A/R were ameliorated and reversed effectively (P<0.05 to 0.01 versus those in other A/R groups). The results also showed that ROS was increased and PAR-1, PAR-2, p38 MAP kinase and p42/44 MAP kinase were all activated after A/R (P<0.001 versus HUVECs under normoxia), while FVIIai inhibited the increment of ROS, PAR-1, PAR-2, p38 MAP kinase and p42/44 MAP kinase, and improved the changes of TF:C, MDA, SOD, GSH-PX, cell viability and LDH occurred during A/R (P<0.05 to 0.001 versus HUVECs without FVIIai treatment). CONCLUSION: Tissue factor plays an important role in the development of HUVECs injury induced by anoxia-reoxygenation, inhibition of TF with antisense oligodeoxynucleotide is an effective approach to ameliorate the damage.

Function of Adenosine 2A Receptor in High-Fat Diet-Induced Peripheral Neuropathy.

Peripheral diabetic neuropathy (DPN) is a complication observed in up to half of all patients with type 2 diabetes. DPN has also been shown to be associated with obesity. High-fat diet (HFD) affects glucose metabolism, and the impaired glucose tolerance can lead to type 2 diabetes. There is evidence to suggest a role of adenosine 2A receptors (A2ARs) and semaphorin 3A (Sema3a) signaling in DPN. The link between the expression of Sema3a and A2AR in DPN was hypothesized, but the underlying mechanisms remain poorly understood. In this study, we investigated the regulation of Sema3a by A2AR in the spinal cord and the functional implications thereof in DPN. We examined the expression of A2ARs and Sema3a, as well as Neuropilin 1 and Plexin A, the coreceptors of Sema3a, in the dorsal horn of the lumbar spinal cord of an animal model with HFD-induced diabetes. Our results demonstrate that HFD dysregulates the A2AR-mediated Sema3a expression, with functional implications for the type 2 diabetes-induced peripheral neuropathy. These observations could stimulate clinical studies to improve our understanding on the subject.

Polymeric Nanoscale Drug Carriers Mediate the Delivery of Methotrexate for Developing Therapeutic Interventions Against Cancer and Rheumatoid Arthritis.

Methotrexate (MTX) is widely used as an anticancer and anti-inflammtory drug for treating various types of cancer and autoimmune diseases. The optimal dose of MTX is known to inhibit the dihydrofolatereductase that hinders the replication of purines. The nanobiomedicine has been extensively explored in the past decade to develop myriad functional nanostructures to facilitate the delivery of therapeutic agents for various medical applications. This review is focused on understanding the design and development of MTX-loaded nanoparticles alongside the inclusion of recent findings for the treatment of cancers. In this paper, we have made a coordinated effort to show the potential of novel drug delivery systems by achieving effective and target-specific delivery of methotrexate.

Investigation on glucocorticoid receptors within platelets from adult patients with immune thrombocytopenia.

Objective: The expression of glucocorticoid receptors within platelets from newly diagnosed Immune Thrombocytopenia (ITP) patients in the adult was investigated.Methods: GR expression in platelets from newly diagnosed ITP patients and healthy controls was measured using flow cytometry. Subsequently, platelets RNA and proteins were isolated and used for confirming the flow cytometry results by using RT-qPCR and ELISA.Results: Flow cytometry showed that the percentages of platelets expressing GRα and GRß from ITP patients were significantly higher than those from healthy controls (P < 0.05). qPCR and ELISA confirmed that GRα and GRß were increased at both RNA transcription and protein expression levels within platelets from ITP patients compared with healthy controls.Conclusion: We speculated that the up-regulation of glucocorticoid receptor within platelets may be an important biological feature of platelets in patients with ITP, and may also play an important role in the treatment of ITP, which is worthy of further study.

Detection of Plasma EGFR Mutations in NSCLC Patients with a Validated ddPCR Lung cfDNA Assay.

Purpose: The clinical utility of cell-free DNA (cfDNA) to assess EGFR mutations is increasing. However, there are limited studies determining their clinical validity and utility. The value of cfDNA assays in cancer management remains controversial. Methods: In this study, we first evaluated the analytical performance of the ddPCR Lung cfDNA Assay. We next analyzed the concordance of the results with tissue amplification refractory mutation system PCR (ARMS-PCR) and plasma next-generation sequencing (NGS) genotyping. Finally, we assessed its clinical utility by exploring the association of cfDNA EGFR mutations with metastatic sites and the efficacy of EGFR-TKIs treatment. Results: The ddPCR Lung cfDNA Assay demonstrated a limit of blank of 1 droplet per reaction, an analytical specificity of 100%, and detection limit of 0.05%, 0.05%, and 0.1% for E746_A750del, L858R, and T790M, respectively. With tissue ARMS-PCR as a standard for comparison, the clinical sensitivity and specificity of ddPCR were 62.5% (15/24) and 100% (82/82) for E746_A750del, and 75.0% (15/20) and 94.2% (81/86) for L858R, respectively. The ddPCR showed high concordance with NGS in determining cfDNA EGFR mutations. Patients with bone and/or brain metastasis showed a higher detection rate and mutant abundance of cfDNA EGFR mutations compared to those with other sites of metastasis. Moreover, EGFR-TKIs treatment was effective in patients with sensitive EGFR mutations in either plasma cfDNA or tumor tissue-derived DNA. Conclusions: We validated in this study that the ddPCR Lung cfDNA Assay is reliable for detection of EGFR mutations in lung cancers, in terms of analytical performance, clinical validity and utility.