Magnetic particle-based chemiluminescence immunoassay for serum human heart-type fatty acid binding protein measurement.

OBJECTIVES: Human heart-type fatty acid binding protein (HFABP) is a biomarker for diagnosis, risk assessment, and prognosis of acute myocardial infarction, and we aimed to establish an immunoassay for HFABP quantitation. METHODS: Human HFABP monoclonal antibodies (mAbs) were developed, evaluated by enzyme-linked immunosorbent assay, and a chemiluminescence enzyme immunoassay (CLEIA) generated. Analytical performance of the CLEIA was evaluated by measuring serum HFABP. RESULTS: The prokaryotically expressed rHFABP was purified and four anti-HFABP mAbs with superior detection performance were obtained after immunizing BALB/c mice. MAbs 2B8 and 6B3 were selected as respective capture and detection antibodies for HFABP measurement by CLEIA (detection range, 0.01-128 µg/L). Results using the CLEIA showed excellent correlation (r, 0.9622) and the correlation coefficient was 0.9809 (P < 0.05) by the Tukey test statistical analysis with those of latex-enhanced immunoturbidimetry in hospitals. CONCLUSION: Our mAbs and CLEIA for HFABP detection represent new diagnostic tools for measurement of human serum HFABP.

[Corrigendum] 7­Difluoromethoxyl­5,4'­di­n­octyl genistein inhibits the stem­like characteristics of gastric cancer stem­like cells and reverses the phenotype of epithelial­mesenchymal transition in gastric cancer cells.

Subsequently to the publication of the above article, an interested reader drew to the authors' attention that there appeared to be two pairs of images in Fig. 2A and B on p. 1159 and Fig. 4 on p. 1161 that contained overlapping sections, such that these figures, which were intending to show the results from differently performed experiments, may have been derived from the same original sources. The authors have examined their original data, and realize that, although Fig. 2 was correct as presented in the article, these data were erroneously and inadvertently included in Fig. 4. The revised version of Fig. 4, which shows the inhibition of sphere­forming ability by 7­difluoromethoxyl­5,4'­di­n­octyl genistein (DOFG) in gastric cancer stem­like cells derived from SGC­7901 cells, is shown below, now including the correct data for the panels showing treatment with 0 and 1.0 µmol/l DOFG, and with re­quantification of these data. The authors are grateful to the Editor of Oncology Reports for allowing them the opportunity to publish a Corrigendum, and all the authors agree with its publication. Furthermore, they apologize to the readership for any inconvenience caused. [Oncology Reports 36: 1157­1165, 2016; DOI: 10.3892/or.2016.4848].

Assess transmissibility of different influenza subtypes: Based on a SEIABR model.

OBJECTIVE: Influenza is a worldwide public health problem which causes a serious economic and health burden. In order to provide a scientific basis for improving the prevention and control level of influenza, using dynamic model to evaluate the infection rates of influenza different subtypes from 2010 to 2019 in China. METHODS: This article established SEIABR model based on influenza cases reported by China National Influenza Center from 2010 to 2019. And calculated the transmission rate and Re by combined the natural birth rate, natural death rate, infectious rate, proportion of asymptomatic patients, proportion of untreated patients, recovery rate and fatality rate. RESULTS: The average infection rate of influenza was (2.38 ± 0.59) × 10-10, and influenza A was (2.24 ± 0.51) × 10-10, influenza B was (2.21 ± 0.68) × 10-10. And average Re were 1.60, 1.51, 1.49. In addition, the infection rates of A /H1N1, A/H3N2, B/Yamagata and B/Victoria were (2.47 ± 0.51) × 10-10, (2.25 ± 0.48) × 10-10, (2.15 ± 0.61) × 10-10, and (2.30 ± 0.66) × 10-10 and average Re were 1.67, 1.52, 1.44, 1.56. CONCLUSION: Between each year, flu transmission capacity had fluctuation. Influenza A was more transmissible than influenza B, and during the major subtypes, influenza A/H1N1 was the most transmissible.

Development of magnetic particle-based chemiluminescence immunoassay for measurement of SARS-CoV-2 nucleocapsid protein.

BACKGROUND: Recently, the Coronavirus Disease 2019 (COVID-19) caused by SARS-CoV-2 infection has spread rapidly around the world, becoming a new global pandemic disease. Nucleic acid detection is the primary method for clinical diagnosis of SARS-CoV-2 infection, with the addition of antibody and antigen detection. Nucleocapsid protein (NP) is a kind of conservative structural protein with abundant expression during SARS-CoV-2 infection, which makes it an ideal target for immunoassay. METHODS: The coding sequence for SARS-CoV-2-NP was obtained by chemical synthesis, and then inserted into pET28a(+). The soluble recombinant NP (rNP) with an estimated molecular weight of 49.4 kDa was expressed in E. coli cells after IPTG induction. Six-week-old BALB/c mice were immunized with rNP, and then their spleen cells were fused with SP2/0 cells, to develop hybridoma cell lines that stably secreted monoclonal antibodies (mAbs) against NP. The mAbs were preliminarily evaluated by enzyme-linked immunosorbent assay (ELISA), and then used to develop a magnetic particle-based chemiluminescence enzyme immunoassay (CLEIA) for measurement of SARS-CoV-2-NP. RESULTS: mAb 15B1 and mAb 18G10 were selected as capture and detection antibody respectively to develop CLEIA, due to the highest sensitivity for rNP detection. The proposed CLEIA presented a good linearity for rNP detection at a working range from 0.1 to 160 µg/L, with a precision coefficient of variance below 10 %. CONCLUSION: The newly developed mAbs and CLEIA can serve as potential diagnostic tools for clinical measurement of SARS-CoV-2-NP.

[Corrigendum] FOXO3a­mediated suppression of the self­renewal capacity of sphere­forming cells derived from the ovarian cancer SKOV3 cell line by 7­difluoromethoxyl­5,4'­di­n­octyl genistein.

Subsequently to the publication of this paper, an interested reader drew to the authors' attention that strikingly similar western blot data were shown in Fig. 2 (to portray the Nagon data in Fig. 2A and the CD133 data in Fig. 2B), and the same data also appeared to have been included in Fig. 4 (to show the p­FOXO3a data). After having examined their original data, the authors have realized that these figures were inadvertently assembled incorrectly. The corrected versions of Figs. 2 and 4, showing the correct data for the CD133 experiment in Fig. 2B and the p­FOXO3a experiment in Fig. 4, are shown opposite. Note that these errors did not significantly affect the results or the conclusions reported in this paper, and all the authors agree to this Corrigendum. Furthermore, the authors apologize to the readership for any inconvenience caused. [the original article was published in Molecular Medicine Reports 9: 1982­1988, 2014; DOI: 10.3892/mmr.2014.2012].

Construction of a Conditionally Asporogenous Bacillus thuringiensis Recombinant Strain Overproducing Cry Protein by Deletion of the leuB Gene.

One of the common shortcomings with Bacillus thuringiensis (Bt) biopesticides in field application is their instability under UV irradiation. In Bt, the leuB gene encodes the 3-isopropylmalate dehydrogenase. In addition to its role in leucine biosynthesis, LeuB would be likely recruited to catalyze the dehydrogenation of malate in the final step of tricarboxylic acid cycle during sporulation. In this study, we constructed a Bt recombinant strain in which the gene leuB was deleted by using the markerless gene deletion system. The ΔleuB mutant strain showed a conditionally asporogenous phenotype while overproducing insecticidal crystal proteins and retaining its insecticidal activity well in both fermentation and LB media. Furthermore, the metabolic regulation mechanisms of LeuB was elucidated by iTRAQ-based quantitative proteomics approach. Evidences from proteomics data suggested that the inhibited supply of pyruvate (carbon source) was an important factor related to the conditionally asporogenous feature of the mutant. Consistently, the mutant regained its ability to sporulate in LB medium by adding 1% glucose or 1% sodium pyruvate. Taken together, our study demonstrated that deletion of the leuB gene resulted in delayed or completely blocked mother cell lysis, allowing the crystals encapsulated within cells, which makes this recombinant strain a good candidate for developing Bt preparations with better UV-stability.

Genistein inhibits lung cancer cell stem-like characteristics by modulating MnSOD and FoxM1 expression.

Manganese superoxide dismutase (MnSOD) promotes invasive and migratory activities by upregulating Forkhead box protein M1 (FoxM1) expression. The present study investigated whether modulation of MnSOD and FoxM1 expression was responsible for the antitumor effects of genistein on cancer stem-like cells (CSLCs) derived from non-small cell lung cancer cells (NSCLCs). Spheroids prepared from H460 or A549 cells were defined as lung cancer stem-like cells (LCSLCs) and were treated with genistein. The Cell Counting Kit-8 assay was performed to assess human lung fibroblast IMR-90 cell proliferation, as well as NSCLC H460 and A549 cell proliferation following treatment with genistein. MnSOD, FoxM1, cluster of differentiation (CD)133, CD44, BMI1 proto-oncogene, polycomb ring finger (Bmi1) and Nanog homeobox (Nanog) protein expression levels were examined via western blotting. The sphere formation assay was conducted to evaluate LCSLC self-renewal potential, and LSCLC migratory and invasive activities were analyzed using the wound healing and Transwell invasion assays, respectively. Knockdown and overexpression of MnSOD and FOXM1 via short hairpin-RNA or cDNA transfection were performed. The results indicated that genistein (80 and 100 µM) suppressed H460 and A549 cell viability compared with IMR-90 cells. Sub-cytotoxic concentrations of genistein (20 and 40 µM) inhibited sphere formation activity and decreased the protein expression levels of CD133, CD44, Bmi1 and Nanog in LCSLCs compared with the control group. Genistein also suppressed the migratory and invasive activities of LCSLCs compared with the control group. MnSOD and FoxM1 overexpression antagonized the effects of genistein (40 µM), whereas MnSOD and FoxM1 knockdown enhanced the inhibitory effects of genistein (20 µM) on CSLC characteristics of LCSLCs. Overall, the results suggested that genistein suppressed lung cancer cell CSLC characteristics by modulating MnSOD and FoxM1 expression levels.

Effects of SpoIVA on the formation of spores and crystal protein in Bacillus thuringiensis.

In addition to forming spores, Bacillus thuringiensis (Bt) 4.0718 can produce toxins, insecticidal crystal protein (ICP) and vegetative insecticidal protein (Vip). The Bt spoIVA was successfully knocked out by gene recombination and was shown to inhibit sporulation. The mutant strain also exhibited significantly decreased growth and crystal formation, which inhibited spore formation and partially reduced the rate of crystal synthesis. The 50 % lethal concentrations (LC50) values of Bt 4.0718, replacement, complementation and multi-copy mutant strains against the fourth larval stage of H. armigera was determined as 5.422, 6.776, 6.223 and 5.018 µg/mL, respectively. A total of 1814 proteins were identified through isobaric tags for relative and absolute protein (iTRAQ), with 41 and 54 up and downregulated proteins observed. Gene ontology enrichment analysis showed that differentially expressed proteins were primarily involved in the biological process and molecular function. Quantitative real-time PCR analysis confirmed that 9 differential expressed genes exhibited a positive correlation between changes at transcriptional and translational levels. The results of this study provide a basis for further studies of the metabolic regulatory network of spores and crystal protein formation. Moreover, they can be used to ecologically safe insecticide of farmland production because the constructed Bt spoIVA mutants did not produce spores.Provides new ideas for the targeted improvement and application of environmentally friendly spore-free strains.

The DNMT1/miR-34a/FOXM1 Axis Contributes to Stemness of Liver Cancer Cells.

BACKGROUND: Whether DNA methyltransferase 1 (DNMT1)/miR-34a/FoxM1 signaling promotes the stemness of liver cancer stem cells (LCSCs) remains unclear. This study aimed to assess whether methylation-based silencing of miR-34a by DNMT1 contributes to stemness features via FoxM1 upregulation in LCSCs. METHODS: The CD133+ subgroup of MHCC97H cells sorted by MACS was used as LCSCs. DNMT1, BMI1, SOX2, and OCT4 mRNA levels, and miR-34a amounts were determined by qRT-PCR. DNMT1, CD44, and FoxM1 proteins were analyzed by immunoblot. Sphere and colony formation abilities were detected by respective assays. CD133+ cell percentages were assessed by flow cytometry. In vivo oncogenicity was evaluated using a tumor xenograft model in mice. The effects of DNMT1/miR-34a signaling on the stemness of LCSCs were examined by knockdown or overexpression of DNMT1 and/or transfection of miR-34a mimic or inhibitor using lentivirus-delivery systems. FoxM1 association with miR-34a was detected by a reporter assay. RESULTS: We here showed that LCSCs exhibited elevated DNMT1 activity and expression, lower miR-34a expression with higher promoter methylation, and stronger stemness, compared with the parental liver cancer cells. DNMT1 knockdown repressed DNMT1, increased miR-34a amounts by promoter demethylation, and reduced stemness in LCSCs, whereas DNMT1 overexpression had the opposite effects in liver cancer cells. Transfection with miR-34a mimic repressed the stemness of LCSCs, while miR-34a inhibitor significantly downregulated miR-34a and enhanced stemness, without affecting DNMT1 in liver cancer cells. MiR-34a mimic rescued the effects of DNMT1 overexpression on the stemness of LCSCs, without affecting DNMT1 expression. Finally, FOXM1 was identified as a direct target by miR-34a in LCSCs. CONCLUSIONS: We revealed that aberrant activation of DNMT1 causes miR-34a promoter methylation and suppression, leading to FoxM1 upregulation by disinhibition and promotion of LCSC stemness. These findings suggest that blockage of DNMT1/miR-34a-mediated FOXM1 upregulation might suppress liver cancer by targeting LCSCs.

Role of hsp20 in the Production of Spores and Insecticidal Crystal Proteins in Bacillus thuringiensis.

The small heat shock protein plays an important role in response to stresses. We wanted to investigate how Hsp20 affects sporulation and production of insecticidal crystal proteins (ICPs) in Bacillus thuringiensis (Bt) at the stationary growth phase when cells are starved. The hsp20 gene was knocked out in Bt4.0718 (wide type), which is a B. thuringiensis strain screened in our laboratory, using endonuclease I-SceI mediated unmarked gene replacement method. Deletion of Hsp20 resulted in a decrease in both sporulation and ICPs production. Bt4-Δhsp20 cells and its ICP did not have a significant difference in shape and size but entered the decline phase 2 h earlier than the Bt4.0718. In order to find the mechanism that underlies these phenotypes, we completed a proteomic study of differentially expressed proteins (DEPs). In Bt4-Δhsp20 cells, 11 DEPs were upregulated and 184 DEPs downregulated. These affected DEPs are involved in multiple metabolic pathways: (1) six DEPs (two upregulated and four downregulated) are directly related to the sporulation and ICPs synthesis; (2) supply of amino acids including amino acid synthesis and protein recycling; (3) the energy supplementation (the tricarboxylic acid cycle and glycolysis); (4) purine metabolism and mRNA stability. These results suggest that hsp20 may be critical in maintaining the homeostasis of B. thuringiensis during the production of spores and ICPs, and could provide new sight into the sporulation and ICPs formation in B. thuringiensis.

Isovitexin reduces carcinogenicity and stemness in hepatic carcinoma stem-like cells by modulating MnSOD and FoxM1.

BACKGROUND: Manganese superoxide dismutase (MnSOD) upregulating FoxM1 have previously been demonstrated promoting lung cancer stemness. Isovitexin exhibits antitumor activities in various cancers. This study aimed to assess whether isovitexin inhibits hepatic carcinoma stem-like cells (HCSLCs) features via regulating MnSOD and FoxM1 expression. METHODS: Second-generation spheres from the hepatic carcinoma cell lines, respectively, were used as HCSLCs. Protein amounts of MnSOD, FoxM1 and stemness-associated markers (CD133, CD44, ALDH1, Bmi1, Nanog and Oct4) were determined by immunoblotting. In vitro carcinogenicity was evaluated by sphere- and colony-formation assays. The effects of isovitexin on HCSLC carcinogenicity and stemness were examined in vitro and in xenograft models. An adenoviral delivery system was employed to manipulate MnSOD and/or FoxM1. Luciferase reporter assay was performed to verify isovitexin downregulated FoxM1 by inhibiting MnSOD-mediated effects of E2F1 and/or Sp1 on activation of FoxM1 promoter. RESULTS: FoxM1 upregulation by MnSOD contributed to carcinogenicity and stemness, with increased sphere- and colony-formation capabilities, upregulated stemness-associated markers and CD133+ subpopulation as well as elevated oncogenicity in vivo in HCSLCs compared with hepatic carcinoma cells. Isovitexin substantially decreased sphere and colony formation rates, and stemness-associated markers in cultured HCSLCs by suppressing MnSOD and FoxM1 expression. Importantly, isovitexin significantly inhibited tumor growth of in nude mice bearing HCSLCs and reduced CD133 protein expression of xenograft in nude mice. MnSOD or FoxM1 knockdown enhanced the effects of isovitexin suppression on carcinogenicity and stemness in HCSLC. MnSOD or FoxM1 overexpression attenuated the effects of isovitexin. Additionally, isovitexin and MnSOD knockdown could inhibit FoxM1 reporter activity via a decreased binding of E2F1 and/or Sp1 onto FoxM1 promoter. FoxM1 overexpression reversed the effects of isovitexin combined with MnSOD knockdown, without affecting MnSOD expression. Moreover, MnSOD knockdown plus thiostrepton, a FoxM1 specific inhibitor, cooperated with isovitexin to repress xenograft tumor growth and downregulate MnSOD and FoxM1 in nude mice bearing HCSLCs from MHCC97H cells. CONCLUSIONS: Isovitexin inhibits carcinogenicity and stemness in HCSLCs by downregulating FoxM1via inhibition of MnSOD.

8-bromo-7-methoxychrysin suppress stemness of SMMC-7721 cells induced by co-culture of liver cancer stem-like cells with hepatic stellate cells.

BACKGROUND: Our previous works have demonstrated that 8-bromo-7-methoxychrysin suppressed stemness of human hepatocellular carcinoma (HCC) cell line SMMC-7721 induced by condition medium from hepatic stellate cell line LX-2 that was activated by liver cancer stem-like cells (LCSCs). However, whether and whereby BrMC inhibits the stemness induced by co-culture of LCSCs and LX-2 cells remains to be investigated. METHODS: The second-generation spheres by sphere culture were identified and used as SMMC-7721-and MHCC97H-derived LCSLCs. SMMC-7721-and MHCC97-derived LCSCs/LX-2 cells transwell co-culture system was treated with BrMC and its lead compound chrysin. The concentrations of IL-6, IL-8, HGF and PDGF in condition medium from co-culture were measured by enzyme-linked immunosorbent assay (ELISA). The stemness of SMMC-7721 cells was evaluated by sphere formation assay and western blot analysis for expression levels of cancer stem cell markers (CD133 and CD44).The expression levels of cancer-associated fibroblast markers (FAP-α and α-SMA) were employed to evaluate pathologic activation of LX-2 cells. Addition of IL-6 and/or HGF or deletion of IL-6 and/or HGF was conducted to investigate the mechanisms for BrMC and chrysin treatment in SMMC-7721-derived LCSLCs co-cultured with LX-2cells. RESULTS: The co-culture of LCSLCs with LX-2 cells increased sphere formation capability as well as expression of CD133 and CD44 in SMMC-7721 cells, meanwhile, upregulated expression of FAP-α in LX-2 cells. ELISA indicated that the concentrations of IL-6 and HGF were significantly elevated in Co-CM than that of condition media from co-cultured SMMC-7721 cells/LX-2 cells. Treatment of BrMC and chrysin with co-cultures of SMMC-7721- and MHCC97H-derived LCSLCs and LX-2 cells effectively inhibited the above responses. Moreover, addition of IL-6 and/or HGF induced stemness of SMMC-7721 cells and activation of LX-2 cells, conversely, deletion of IL-6 and/or HGF suppressed those. Furthermore, the inhibitory effects of BrMC and chrysin on stemness of SMMC-7721 cells and activation of LX-2 cells were attenuated by addition of IL-6 or HGF, and enhanced by deletion of IL-6 or HGF. CONCLUSIONS: Our results suggest IL-6 and HGF may be the key communication molecules for the interaction between LCSLCs and HSCs, and BrMC and chrysin could block these effects and be the novel therapeutic candidates for HCC management.

Genistein inhibits stemness of SKOV3 cells induced by macrophages co-cultured with ovarian cancer stem-like cells through IL-8/STAT3 axis.

BACKGROUND: Recent studies showed that macrophages co-cultured with ovarian cancer stem-like cells (OCSLCs) induced SKOV3 cell stemness via IL-8/STAT3 signaling. Genistein (GEN) demonstrates chemopreventive activity in inflammation-associated cancers. The present study aimed to examine whether and if GEN inhibits the stemness of SKOV3 and OVCA-3R cells induced by co-culture of THP-1 macrophages and SKOV3-derived OCSLCs. METHODS: The co-culture was treated with or without different concentrations (10, 20, and 40 µmol/L) of GEN for 24 h. Depletion or addition of IL-8 in Co-CM and knockdown or overexpression of STAT3 in THP-1 macrophages was performed to demonstrate the possible associated mechanisms. The combined effects of GEN and STAT3 knockdown were examined with the nude mouse modle by co-injection of SKOV3-derived OCSLCs with THP-1 macrophages. RESULTS: Our results showed that GEN down-regulated CD163 and p-STAT3 expression of THP-1 macrophage, decreased the levels of IL-10, increased the levels of IL-12 and nitric oxide (NO) in the conditioned medium, and reduced the clonogenic and sphere-forming capacities and the expression of CD133 and CD44 in SKOV3 cells induced by co-culture of THP-1 macrophages and OCSLCs in a dose-dependent manner. Moreover, depletion or addition of IL-8 enhanced or attenuated the effect of GEN. Additionally, knockdown or overepression of STAT3 in THP-1 macrophages potentiated or attenuated the inhibitory effects of GEN. Importantly, STAT3 overexpression retrieved the effects of IL-8 combined with GEN depletion on M2 polarization of THP-1 macrophages and stemness of SKOV3 cells induced by co-culture. The combination of GEN and STAT3 knockdown cooperatively inhibited the growth of tumors co-inoculated with OCSLCs/THP-1 macrophages in nude mice in vivo through blocking IL-8/STAT3 signaling. CONCLUSIONS: In summary, our findings suggested that GEN can inhibit the increased M2 polarization of macrophages and stemness of ovarian cancer cells by co-culture of macrophages with OCSLCs through disrupting IL-8/STAT3 signaling axis. This assisted GEN to be as a potential chemotherapeutic agent in human ovarian cancer.

8-bromo-7-methoxychrysin Reversed M2 Polarization of Tumor-associated Macrophages Induced by Liver Cancer Stem-like Cells.

BACKGROUND: Hepatocellular carcinoma (HCC) is related to chronic liver inflammation. M2 polarization of tumor-associated macrophages (TAMs) in the tumor microenvironment promotes liver cancer stem-like cell (LCSLC) self-renewal capability and carcinogenicity. Therefore, reversing M2 polarization of TAMs could be an effective approach to cure HCC. OBJECTIVE: To evaluate whether 8-bromo-7-methoxychrysin (BrMC) has an effect on M2 polarization of TAMs. METHOD: LCSLC and conditional medium were obtained by sphere forming assay. Identification of LCSLC were analyzed by sphere forming, wound-healing and invasion assay. TAM and effects of BrMC on it were validated by immunofluorescence staining, ELISA and griess assay. Expressions of cancer stem cell and macrophage marker were analyzed by western blotting. RESULTS: Our results showed that BrMC significantly suppressed the expression of the M2 macrophage marker CD163. Furthermore, BrMC influenced the secretion profile of cytokines of TAMs. Mechanistically, BrMC reversed M2 polarization of TAMs due to inhibition of NF-κB activation. CONCLUSION: BrMC may be a potentially novel flavonoid agent that can be applied for disrupting the interaction of LCSLCs and TAMs.

A candidate Chinese medicine preparation-Fructus Viticis Total Flavonoids inhibits stem-like characteristics of lung cancer stem-like cells.

BACKGROUND: Cancer stem cells (CSCs) are considered as the origin of tumor relapse. Here, we investigated the effects of Fructus Viticis total flavonoids (FVTF) on the characteristics of lung cancer stem-like cells (LCSLCs) derived from human small cell lung cancer NCI-H446 cell line and its potential mechanism. METHODS: Human small cell lung cancer NCI-H446 cell line was cultured in vitro. The CD133(+) cells were sorted from NCI-H446 cell line by magnetic separation. The suspended culture with stem cell-conditioned medium was used to amplify CD133(+) sphere-forming cells (SFCs). The stem cell characteristics of CD133(+) SFCs were evaluated using cell self-renewal capacity by tumor sphere formation assay, migration and invasion capacity by Transwell assay, tumorigenicity by xenograft model in nude mouse and cancer stem cell markers expression levels by western blot. The effects of FVTF on the properties of LCSLCs were examined by tumorsphere formation assay and transwell chamber assay. The expression level of p-Akt was determined by western blot analysis. RESULT: CD133(+) SFCs derived from human small cell lung cancer NCI-H446 cells exhibited stemness properties of tumorsphere formation and tumorigenesis capacity comparing to the parental cells. FVTF relative selectively inhibited the proliferation of LCSLCs, suppressed tumor sphere forming capacity and migration and invasion of LCSLCs, and down-regulated the protein expression of stem cell markers (CD133, CD44 and ALDH1), self-renewal associated transcription factors (Bmi1, Nanog and OCT4) and invasion associated transcription factors (Twist1 and Snail1) in a dose-dependent manner. Moreover, we found that FVTF treatment could significantly decrease the phosphorylation level of Akt in LCSLCs. Meanwhile, LY294002 and FVTF synergistically inhibited the characteristics of LCSLCs. CONCLUSION: FVTF inhibits the characteristics of LCSLCs through down-regulating expression of p-Akt.