Combining primary tumor features derived from conventional and contrast-enhanced ultrasound facilitates the prediction of positive axillary lymph nodes in Breast Imaging Reporting and Data System category 4 malignant breast lesions.

PURPOSE: To determine whether the primary tumor features derived from conventional ultrasound (US) and contrast-enhanced US (CEUS) facilitate the prediction of positive axillary lymph nodes (ALNs) in breast cancer diagnosed as Breast Imaging Reporting and Data System (BI-RADS) category 4. METHODS: A total of 240 women with breast cancer who underwent preoperative conventional US, strain elastography, and CEUS between September 2016 and December 2019 were included. The multiple parameters of the primary tumor were obtained, and univariate and multivariate analyses were performed to predict positive ALNs. Then three prediction models (conventional US features, CEUS features, and the combined features) were developed, and the diagnostic performance was evaluated with receiver operating characteristic curves. RESULTS: On conventional US, the traits of large size and the non-circumscribed margin of the primary tumor were marked as two independent predictors. On CEUS, the features of vessel perforation or distortion and the enhanced range of the primary tumor were marked as two independent predictors for positive ALNs. Three prediction models were then developed: model A (conventional US features), model B (CEUS features), and model C (model A plus B). Model C yielded the highest area under the curve (AUC) of 0.82 [95% confidence interval (CI), 0.75-0.88] compared with model A (AUC 0.74; 95% CI, 0.68-0.81; P = 0.008) and model B (AUC 0.72; 95% CI, 0.65-0.80; P < 0.001) as per the DeLong test. CONCLUSION: CEUS, as a non-invasive examination technique, can be used to predict ALN metastasis. Combining conventional US and CEUS may produce favorable predictive accuracy for positive ALNs in BI-RADS category 4 breast cancer.

Cortisol Stimulates Local Progesterone Withdrawal Through Induction of AKR1C1 in Human Amnion Fibroblasts at Parturition.

Fetal membrane activation is seen as being one of the crucial triggering components of human parturition. Increased prostaglandin E2 (PGE2) production, a common mediator of labor onset in virtually all species, is recognized as one of the landmark events of membrane activation. Fetal membranes are also equipped with a high capacity of cortisol regeneration by 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1), and the cortisol regenerated potently induces PGE2 synthesis, an effect normally suppressed by progesterone during gestation. There is no precipitous decline of progesterone synthesis in human parturition. It is intriguing how this suppression is lifted in parturition. Here, we investigated this issue by using human amnion tissue and primary amnion fibroblasts which synthesize the most PGE2 in the fetal membranes. Results showed that the expression of 11ß-HSD1 and aldo-keto reductase family 1 member C1 (AKR1C1), a progesterone-inactivating enzyme, increased in parallel in human amnion tissue with gestational age toward the end of gestation and at parturition. Cortisol induced AKR1C1 expression via the transcription factor CCAAT enhancer binding protein δ (C/EBPδ) in amnion fibroblasts. Inhibition of AKR1C1 not only blocked progesterone catabolism induced by cortisol, but also enhanced the suppression of cortisol-induced cyclooxygenase-2 (COX-2) expression by progesterone in amnion fibroblasts. In conclusion, our results indicate that cortisol regenerated in the fetal membranes triggers local progesterone withdrawal through enhancement of AKR1C1-mediated progesterone catabolism in amnion fibroblasts, so that the suppression of progesterone on the induction of COX-2 expression and PGE2 synthesis by cortisol can be lifted for parturition.

BCL-2 inhibitor synergizes with PI3Kδ inhibitor and overcomes FLT3 inhibitor resistance in acute myeloid leukaemia.

Inhibitors targeting the antiapoptotic molecule BCL-2 have therapeutic potential for the treatment of acute myeloid leukaemia (AML); however, BCL-2 inhibitors such as venetoclax exhibit limited monotherapy efficacy in relapsed or refractory human AML. PI3Kδ/AKT signalling has been shown to be constitutively active in AML patients. Here, we demonstrate that the combination of BCL-2 and PI3Kδ inhibitors exerts synergistic antitumour effects both in vitro and in vivo in AML. Cotreatment with venetoclax and the specific PI3Kδ inhibitor idelalisib significantly enhanced antiproliferative effects and induced caspase-dependent apoptosis in a panel of AML cell lines. The synergistic effects were mechanistically based on the inactivation of AKT/4E-BP-1 signalling and the reduction of MCL-1 expression, which diminished the binding of Bim to MCL-1. Notably, compared with the parental FLT3-ITD-positive MV-4-11, the acquired FLT3 inhibitor quizartinib-resistant xenograft model carrying the F691L mutation, exhibited a markedly higher sensitivity to venetoclax. Furthermore, venetoclax combined with idelalisib led to tumour regression in all animals in this quizartinib-resistant AML model. Thus, these data indicate that combined inhibition of BCL-2 and PI3Kδ may be a promising strategy in AML, especially for patients with FLT3-ITD and/or FLT3-TKD mutations.

Adding contrast-enhanced ultrasound markers to conventional axillary ultrasound improves specificity for predicting axillary lymph node metastasis in patients with breast cancer.

OBJECTIVE: To evaluate the diagnostic performance of contrast-enhanced ultrasound (CEUS) combined with conventional ultrasound of axillary lymph nodes (ALNs) in predicting metastatic ALNs in patients with breast cancer. METHODS: This retrospective study included 259 patients with breast cancer who underwent conventional ultrasound and CEUS. The parameters and patterns evaluated on conventional ultrasound included short axis diameter (S), long axis/short axis (L/S) ratio, cortical thickness, resistive index (RI), lymph node (LN) morphology of greyscale ultrasound, hilum and vascular pattern. Meanwhile, enhancement pattern, wash-in time, time to peak (TP), maximum signal intensity, and duration of contrast enhancement were evaluated on CEUS. Univariate and multiple logistic regression analyses were performed to identify independent factors of ALN status. Three models (conventional ultrasound, CEUS, and combined parameters) were established. Receiver operating characteristic (ROC) curves were applied to evaluate the accuracy of the three predictive models. RESULTS: On conventional axillary ultrasound, LN morphology and vascular pattern were independent factors in predicting metastatic ALNs. On CEUS, maximum signal intensity, duration of contrast enhancement, and TP were independent factors in predicting metastatic ALNs. When combining conventional ultrasound and CEUS features, five independent factors obtained from the conventional ultrasound and CEUS were associated with ALN status. ROC curve analysis showed that the use of CEUS markers combined with conventional ultrasound features (AUC = 0.965) was superior to the use of CEUS markers (AUC = 0.936) and conventional ultrasound features alone (AUC = 0.851). CONCLUSION: Combining conventional ultrasound and CEUS features can enable discrimination of ALN status better than the use of CEUS and conventional ultrasound features alone. ADVANCES IN KNOWLEDGE: The axillary lymph node status in breast cancer patients impacts the treatment decision. Our ultrasonic data demonstrated that CEUS features of ALNs in breast cancer patients could be image markers for predicting ALN status. Combining conventional ultrasound and CEUS features of ALNs can improve specificity discrimination of ALN status better than the use of CEUS and the conventional ultrasound features alone, which will help the treatment planning optimization.

De novo Synthesis of SAA1 in the Placenta Participates in Parturition.

Serum amyloid A1 (SAA1) is an acute phase protein produced mainly by the liver to participate in immunomodulation in both sterile and non-sterile inflammation. However, non-hepatic tissues can also synthesize SAA1. It remains to be determined whether SAA1 synthesized locally in the placenta participates in parturition via eliciting inflammatory reactions. In this study, we investigated this issue by using human placenta and a mouse model. We found that SAA1 mRNA and protein were present in human placental villous trophoblasts, which was increased upon syncytialization as well as treatments with lipopolysaccharides (LPS), tumor necrosis factor-α (TNF-α), and cortisol. Moreover, significant increases in SAA1 abundance were observed in the placental tissue or in the maternal blood in spontaneous deliveries without infection at term and in preterm birth with histological chorioamnionitis. Serum amyloid A1 treatment significantly increased parturition-pertinent inflammatory gene expression including interleukin-1ß (IL-1ß), IL-8, TNF-α, and cyclooxygenase-2 (COX-2), along with increased PGF2α production in syncytiotrophoblasts. Mouse study showed that SAA1 was present in the placental junctional zone and yolk sac membrane, which was increased following intraperitoneal administration of LPS. Intraperitoneal injection of SAA1 not only induced preterm birth but also increased the abundance of IL-1ß, TNF-α, and COX-2 in the mouse placenta. Conclusively, SAA1 can be synthesized in the human placenta, which is increased upon trophoblast syncytialization. Parturition is accompanied with increased SAA1 abundance in the placenta. Serum amyloid A1 may participate in parturition in the presence and absence of infection by inducing the expression of inflammatory genes in the placenta.

Flavonoids from Houttuynia cordata attenuate H1N1-induced acute lung injury in mice via inhibition of influenza virus and Toll-like receptor signalling.

BACKGROUND: Influenza virus is one of the most important human pathogens, causing substantial seasonal and pandemic morbidity and mortality. Houttuynia cordata is a traditionally used medicinal plant for the treatment of pneumonia. Flavonoids are one of the major bioactive constituents of Houttuynia cordata. PURPOSE: This study was designed to investigate the therapeutic effect and mechanism of flavonoid glycosides from H. cordata on influenza A virus (IAV)-induced acute lung injury (ALI) in mice. METHODS: Flavonoids from H. cordata (HCF) were extracted from H. cordata and identified by high-performance liquid chromatography. Mice were infected intranasally with influenza virus H1N1 (A/FM/1/47). HCF (50, 100, or 200 mg/kg) or Ribavirin (100 mg/kg, the positive control) were administered intragastrically. Survival rates, life spans, weight losses, lung indexes, histological changes, inflammatory infiltration, and inflammatory markers in the lungs were measured. Lung virus titers and neuraminidase (NA) activities were detected. The expression of Toll-like receptors (TLRs) and levels of NF-κB p65 phosphorylation (NF-κB p65(p)) in the lungs were analysed. The effects of HCF on viral replication and TLR signalling were further evaluated in cells. RESULTS: HCF contained 78.5% flavonoid glycosides. The contents of rutin, hyperin, isoquercitrin, and quercitrin in HCF were 8.8%, 26.7%, 9.9% and 31.7%. HCF (50, 100 and 200 mg/kg) increased the survival rate and life span of mice infected with the lethal H1N1 virus. In H1N1-induced ALI, mice treated with HCF (50, 100 and 200 mg/kg) showed lesser weight loss and lower lung index than the model group. The lungs of HCF-treated ALI mice presented more intact lung microstructural morphology, milder inflammatory infiltration, and lower levels of monocyte chemotactic protein 1 (MCP-1), interleukin-8 (IL-8), tumor necrosis factor-α (TNF-α) and malondialdehyde (MDA) than in the model group. Further investigation revealed that HCF exerted antiviral and TLR-inhibitory effects in vivo and in vitro. HCF (50, 100 and 200 mg/kg) reduced lung H1N1 virus titers and inhibited viral NA activity in mice. HCF (100 and 200 mg/kg) elevated the levels of interferon-ß in lungs. HCF also decreased the expression of TLR3/4/7 and level of NF-κB p65(p) in lung tissues. In vitro experiments showed that HCF (50, 100 and 200 µg/ml) significantly inhibited viral proliferation and suppressed NA activity. In RAW 264.7 cells, TLR3, TLR4, and TLR7 agonist-stimulated cytokine secretion, NF-κB p65 phosphorylation, and nuclear translocation were constrained by HCF treatment. Furthermore, among the four major flavonoid glycosides in HCF, hyperin and quercitrin inhibited both viral replication and TLR signalling in cells. CONCLUSION: HCF significantly alleviated H1N1-induced ALI in mice, which were associated with its dual antiviral and anti-inflammatory effects via inhibiting influenzal NA activity and TLR signalling. among the four major flavonoid glycosides in HCF, hyperin and quercitrin played key roles in the therapeutic effect of HCF.

Comparison of Diagnostic Efficacy Between Contrast-Enhanced Ultrasound and DCE-MRI for Mass- and Non-Mass-Like Enhancement Types in Breast Lesions.

BACKGROUND: Contrast-enhanced ultrasound (CEUS) can provide angiogenesis information about breast lesions; however, its diagnostic performance in comparison with that of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) has not been systematically investigated. This study aimed to evaluate the diagnostic efficacy of CEUS and DCE-MRI in mass-like and non-mass-like enhancement types of breast lesions. MATERIAL AND METHODS: A retrospective study was conducted on 252 patients with breast lesions who underwent CEUS and DCE-MRI before surgery between January 2016 and February 2020. Histopathological results were used as reference standards. All patients were classified into mass-like and non-mass-like enhancement lesion groups. The mass-like lesion group was further divided into three categories according to different sizes (group 1: <10 mm, group 2: 10-20 mm, and group 3: >20 mm). Sensitivity, specificity, positive predictive value, negative predictive value, and receiver operating characteristic curve were analyzed to assess the diagnostic performance of these two modalities. RESULTS: For mass-like breast lesions, DCE-MRI (Az=0.981) manifested better diagnostic performance than CEUS (Az=0.940) in medium-sized (10-20 mm) tumors (Z=2.018, P=0.043), but both had similar diagnostic performance in smaller (<10 mm) and larger (>20 mm) tumors (P=0.717, P=0.394). For non-mass-like enhancement lesions, CEUS and DCE-MRI showed no significant difference (Z=1.590, P=0.119) and revealed good diagnostic performance (Az=0.859, Az=0.947) in differentiating the two groups. CONCLUSION: For mass-like breast lesions, DCE-MRI showed better diagnostic performance than CEUS in differentiating benign and malignant tumors of medium-sizes (10-20mm) but not of smaller (<10mm) and larger (>20 mm) sizes. For non-mass-like lesions, both modalities showed similar diagnostic performance.

Diagnostic performance of contrast-enhanced ultrasound and enhanced magnetic resonance for breast nodules.

In the current study, we sought to evaluate the diagnostic efficacies of conventional ultrasound (US), contrast-enhanced US (CEUS), combined US and CEUS and magnetic resonance imaging (MRI) in detecting focal solid breast lesions. Totally 117 patients with 120 BI-RADS category 4A-5 breast lesions were evaluated by conventional US and CEUS, and MRI, respectively. SonoVue was used as contrast agent in CEUS and injected as an intravenous bolus; nodule scan was performed 4 minutes after bolus injection. A specific sonographic quantification software was used to obtain color-coded maps of perfusion parameters for the investigated lesion, namely the time-intensity curve. The pattern of contrast enhancement and related indexes regarding the time-intensity curve were used to describe the lesions, comparatively with pathological results. Histopathologic examination revealed 46 benign and 74 malignant lesions. Sensitivity, specificity, and accuracy of US in detecting malignant breast lesions were 90.14%, 95.92%, and 92.52%, respectively. Meanwhile, CE-MRI showed sensitivity, specificity, and accuracy of 88.73%, 95.92%, and 91.67%, respectively. The area under the ROC curve for combined US and CEUS in discriminating benign from malignant breast lesions was 0.936, while that of MRI was 0.923, with no significant difference between them, as well as among groups. The time-intensity curve of malignant hypervascular fibroadenoma and papillary lesions mostly showed a fast-in/fast-out pattern, with no good correlation between them (kappa < 0.20). In conclusion, the combined use of conventional US and CEUS displays good agreement with MRI in differentiating benign from malignant breast lesions.

Shikonin reduces tamoxifen resistance through long non-coding RNA uc.57.

Tamoxifen resistance is a serious problem in the endocrine therapy of breast cancer. Long non-coding RNAs play important roles in tumor development. In this study, we revealed the involvement of lncRNA uc.57 and its downstream gene BCL11A in TAM resistance. Tamoxifen-resistant MCF-7R cells showed lower expression of uc.57 and higher expression of BCL11A mRNA and protein than the parental MCF-7 cells. Moreover, levels of uc.57 mRNA were lower and BCL11A mRNA were higher in breast cancer tissues than in precancerous breast tissues. Shikonin treatment reduced tamoxifen resistance in MCF-7R cells both in vitro and in vivo, targeting uc.57/BCL11A. Fluorescence in situ hybridization and RNA immunoprecipitation analyses showed that uc.57 binds to BCL11A. Uc.57 overexpression downregulated BCL11A and reduced tamoxifen resistance in MCF-7R cells both in vitro and in vivo. BCL11A knockdown also reduced tamoxifen resistance by inhibiting PI3K/AKT and MAPK signaling pathways. It thus appears shikonin reduces tamoxifen resistance of MCF-7R breast cancer cells by inducing uc.57, which downregulates BCL11A to inhibit PI3K/AKT and MAPK signaling pathways.

uc.38 induces breast cancer cell apoptosis via PBX1.

Long non-coding RNAs (lncRNAs) are transcripts longer than 200 bp with no protein-coding capacity. Transcribed ultraconserved regions (T-UCRs) are a type of lncRNA and are conserved among human, chick, dog, mouse and rat genomes. These sequences are involved in cancer biology and tumourigenesis. Nevertheless, the clinical significance and biological mechanism of T-UCRs in breast cancer remain largely unknown. The expression of uc.38, a T-UCR, was down-regulated in both breast cancer tissues and breast cancer cell lines. However, uc.38 was expressed at significantly lower levels in larger tumours and tumours of more advanced stages. Based on the results of in vitro and in vivo experiments, up-regulation of uc.38 expression inhibited cell proliferation and induced cell apoptosis. Thus, uc.38 suppressed breast cancer. Additional experiments revealed that uc.38 negatively regulated the expression of the pre-B-cell leukaemia homeobox 1 (PBX1) protein and subsequently affected the expression of Bcl-2 family members, ultimately inducing breast cancer cell apoptosis. Describing the uc.38/PBX1 axis has improved our understanding of the molecular mechanisms involved in breast cancer apoptosis and has suggested that this axis is a potential therapeutic target for breast cancer.

Human mammary microenvironment better regulates the biology of human breast cancer in humanized mouse model.

During the past decades, many efforts have been made in mimicking the clinical progress of human cancer in mouse models. Previously, we developed a human breast tissue-derived (HB) mouse model. Theoretically, it may mimic the interactions between "species-specific" mammary microenvironment of human origin and human breast cancer cells. However, detailed evidences are absent. The present study (in vivo, cellular, and molecular experiments) was designed to explore the regulatory role of human mammary microenvironment in the progress of human breast cancer cells. Subcutaneous (SUB), mammary fat pad (MFP), and HB mouse models were developed for in vivo comparisons. Then, the orthotopic tumor masses from three different mouse models were collected for primary culture. Finally, the biology of primary cultured human breast cancer cells was compared by cellular and molecular experiments. Results of in vivo mouse models indicated that human breast cancer cells grew better in human mammary microenvironment. Cellular and molecular experiments confirmed that primary cultured human breast cancer cells from HB mouse model showed a better proliferative and anti-apoptotic biology than those from SUB to MFP mouse models. Meanwhile, primary cultured human breast cancer cells from HB mouse model also obtained the migratory and invasive biology for "species-specific" tissue metastasis to human tissues. Comprehensive analyses suggest that "species-specific" mammary microenvironment of human origin better regulates the biology of human breast cancer cells in our humanized mouse model of breast cancer, which is more consistent with the clinical progress of human breast cancer.

Novel shikonin derivatives targeting tubulin as anticancer agents.

In this study, we report the identification of a new shikonin-phenoxyacetic acid derivative, as an inhibitor of tubulin. A series of compounds were prepared; among them, compound 16 [(R)-1-(5,8-dihydroxy-1,4-dioxo-1,4-dihydronaphthalen-2-yl)-4-methylpent-3-enyl 2-(4- phenoxyphenyl) acetate] potently inhibited the function of microtubules, inducing cell growth inhibition, apoptosis of cancer cell lines in a concentration and time-dependent manner. Molecular docking involving 16 at the vinblastine binding site of tubulin indicated that a phenoxy moiety interacted with tubulin via hydrogen bonding with asparaginate (Asn) and tyrosine (Tyr). Analysis of microtubules with confocal microscopy demonstrated that 16 altered the microtubule architecture and exhibited a significant reduction in microtubule density. Cell cycle assay further proved that HepG2 cells were blocked in G2/M phase. Our study provides a new, promising compound for the development of tubulin inhibitors by proposing a new target for the anticancer activity of shikonin.

Comprehensive evaluation of the adenovirus/alphavirus-replicon chimeric vector-based vaccine rAdV-SFV-E2 against classical swine fever.

Classical swine fever (CSF) is an economically important, highly contagious swine disease caused by classical swine fever virus (CSFV). Marker vaccines and companion serological diagnostic tests are thought to be a promising strategy for future control and eradication of CSF. Previously, we have demonstrated that an adenovirus-vectored Semliki forest virus replicon construct expressing the E2 glycoprotein from CSFV, rAdV-SFV-E2, induced sterile immunity against a lethal CSFV challenge. In this study, we further evaluated the vaccine with respect to its safety, number and dose of immunization, and effects of maternally derived antibodies, re-immunization of the vaccine or co-administration with pseudorabies vaccine on the vaccine efficacy. The results showed that: (1) the vaccine was safe for mice, rabbits and pigs; (2) two immunizations with a dose as low as 6.25×10(5) TCID(50) or a single immunization with a dose of 10(7) TCID(50) rAdV-SFV-E2 provided complete protection against a lethal CSFV challenge; (3) maternally derived antibodies had no inhibitory effects on the efficacy of the vaccine; (4) the vaccine did not induce interfering anti-vector immunity; and (5) co-administration of rAdV-SFV-E2 with a live pseudorabies vaccine induced antibodies and protection indistinguishable from immunization with either vaccine administered alone. Taken together, the chimeric vaccine represents a promising marker vaccine candidate for control and eradication of CSF.

A novel mouse model of gastric cancer with human gastric microenvironment.

Mouse models play an irreplaceable role in the in vivo research of human gastric cancer. In this study, we developed a novel human Gastric tissue-derived Orthotopic and Metastatic (GOM) mouse model of human gastric cancer, in which the human normal gastric tissues were implanted subcutaneously into immunodeficient mice to create a human gastric microenvironment. Then, human gastric cancer cells were injected into the implants. GOM model could mimic the interactions between human gastric microenvironment and human gastric cancer cells, which help exhibit the real characteristics of tumor cells, and finally mimic the clinical-like tumor proliferation and metastases of human beings.

Ectopic expression of RhoBTB2 inhibits migration and invasion of human breast cancer cells.

RhoBTB2, or Deleted in Breast Cancer 2 (DBC2), identified as a candidate tumor suppressor gene for breast cancer and other human malignancies, is an atypical member of a novel gene family encoding small GTPases. In this study, we found that ectopic expression of RhoBTB2 inhibits the migration and invasion of the human metastatic breast cancer cell lines MDA-MB-231 and MDA-MB-435 in a dose-dependent manner. Western blotting analysis revealed that ectopic expression of RhoBTB2 induces a significant increase in the breast cancer metastasis suppressor, BRMS1. siRNA suppression of BRMS1 expression markedly reversed the inhibitory effects of RhoBTB2 on the migration and invasion abilities of both cell lines. Ezrin is a member of the ezrin-radixin-moesin cytoskeleton-associated protein family and is a key signaling molecule that regulates cancer migration and invasion. Western blotting analysis demonstrated that ectopic expression of RhoBTB2 results in decreased phosphorylation of ezrin and Akt2 in both MDA-MB-231 and MDA-MB-435 cells. Therefore, we conclude that up-regulation of the breast cancer metastasis suppressor BRMS1 and down-regulation of the phosphorylation of the cancer metastasis-related gene, ezrin, contributed to RhoBTB2-induced inhibition of metastatic breast carcinoma cell migration and invasion. Our findings suggest that understanding RhoBTB2-mediated migration and suppression of invasion is critical to the development of new therapies designed to prevent and treat patients with breast cancer metastasis.

Incidence of chemotherapy-induced amenorrhea associated with epirubicin, docetaxel and navelbine in younger breast cancer patients.

BACKGROUND: The rates of chemotherapy-induced amenorrhea (CIA) associated with docetaxel-based regimens reported by previous studies are discordant. For navelbine-based chemotherapies, rates of CIA have seldom been reported. METHODS: Of 170 premenopausal patients recruited between January 2003 and September 2008, 78 were treated with fluorouracil plus epirubicin and cyclophosphamide (FEC), 66 were treated with docetaxel plus epirubicin (TE), and 26 were treated with navelbine plus epirubicin (NE). Patient follow-up was carried up every 3-4 months during the first year, then every 9-12 months during subsequent years. RESULTS: In univariate analysis, the rates of CIA were 44.87% for the FEC regimen, 30.30% for the TE regimen and 23.08% for the NE regimen (P = 0.068). Significant differences in the rates of CIA were not found between the FEC and TE treatment groups (P > 0.05), but were found between the FEC and NE treatment groups (P < 0.05). Furthermore, no significant differences were found between the TE and NE regimens (P > 0.05). Tamoxifen use was a significant predictor for CIA (P = 0.001), and age was also a significant predictor (P < 0.001). In multivariate analysis, age (P < 0.001), the type of chemotherapy regimens (P = 0.009) and tamoxifen use (P = 0.003) were all significant predictors. CONCLUSIONS: Age and administration of tamoxifen were found to be significant predictive factors of CIA, whereas docetaxel and navelbine based regimens were not associated with higher rates of CIA than epirubicin-based regimen.

Human tissue-specific microenvironment: an essential requirement for mouse models of breast cancer.

An ideal mouse model should closely mimic a clinical situation. However, for most models available, this is not the case since clinical trials frequently fail to reproduce the highly encouraging therapeutic results obtained from pre-clinical studies performed using mouse models. In this study, in the process of extending the application of our previously established breast tissue-derived orthotopic and metastatic (BOM) model, the human breast cancer cell line MDA-MB-231 failed to exhibit any osteotropic features that differed from previous studies. Our observations suggest that a human tissue-specific microenvironment could be an essential requirement for a successful mouse model of breast cancer. Here, multiple in vivo breast cancer models were used to confirm this hypothesis. Human breast tissue and cancellated bone were transplanted subcutaneously to female severe combined immunodeficiency disease (SCID) mice by different assemblies, to build several mouse models termed 'breast-breast', 'breast-bone', 'bone-bone', 'MFP (mouse mammary fat pad)-bone', and 'MFP-breast' models. Two human breast cancer cell lines, MDA-MB-231 and MDA-MB-231BO, and the mouse breast cancer cell line TM40D were used. All cancer cells were labeled with GFP for gross observation. In addition, transplanted human tissues and various mouse tissues including bone, lung, liver, mesentery were examined microscopically. Based on morphological, immunohistochemical, and enzymohistochemical evidence obtained from several comparative experiments in 'breast-breast', 'breast-bone' and 'bone-bone' models, the BOM model was proved to be feasible and reliable. The organ tropism of the breast cancer cell line, which was derived from a mouse model by intracardiac inoculation in a pure mouse microenvironment, was reconsidered. The behavior of breast cancer cells in the mouse model was altered in response to the varying microenvironment. The results in this study suggest the human tissue-specific micro-environment is most likely an essential requirement in mouse models of breast cancer.

A novel mouse model of human breast cancer stem-like cells with high CD44+CD24-/lower phenotype metastasis to human bone.

BACKGROUND: A satisfactory animal model of breast cancer metastasizing to bone is unavailable. In this study, we used human breast cancer stem-like cells and human bone to build a novel "human-source" model of human breast cancer skeletal metastasis. METHODS: Human breast cancer stem-like cells, the CD44+/CD24-/lower subpopulation, was separated and cultured. Before injection with the stem-like cells, mice were implanted with human bone in the right or left dorsal flanks. Animals in Groups A, B, and C were injected with 1 x 10(5), 1 x 10(6) human breast cancer stem-like cells, and 1 x 10(6) parental MDA-MB-231 cells, respectively. A positive control group (D) without implantation of human bone was also injected with 1 x 10(6) MDA-MB-231 cells. Immunohistochemistry was performed for determination of CD34, CD105, smooth muscle antibody, CD44, CD24, cytokine, CXC chemokine receptor-4 (CXCR4), and osteopontin (OPN). mRNA levels of CD44, CD24, CXCR4, and OPN in bone metastasis tissues were analyzed by real-time quantitative polymerase chain reaction (PCR). RESULTS: Our results demonstrated that cells in implanted human bones of group B, which received 1 x 10(6) cancer stem-like cells, stained strongly positive for CD44, CXCR4, and OPN, whereas those of other groups showed no or minimum staining. Moreover, group B had the highest incidence of human bone metastasis (77.8%, P = 0.0230) and no accompaniment of other tissue metastasis. The real-time PCR showed an increase of CD44, CXCR4, and OPN mRNA in metastatic bone tissues in group B compared with those of groups C and D, however the expression of CD24 mRNA in group B were the lowest. CONCLUSIONS: In the novel "human source" model of breast cancer, breast cancer stem-like cells demonstrated a higher human bone-seeking ability. Its mechanism might be related to the higher expressions of CD44, CXCR4, and OPN, and the lower expression of CD24 in breast cancer stem-like cells.

Induction of apoptosis by recombinant soluble human TRAIL in Jurkat cells.

OBJECTIVE: To investigate the therapeutic potential of tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), a member of the TNF superfamily, and to analyze TRAIL-induced apoptosis in Jurkat cells. METHODS: Expression of TRAIL receptors (DR4 and DR5) was detected by reverse transcriptase-polymerase chain reaction (RT-PCR). Cytotoxic effects were determined by colony formation assay and a cell counting kit. The effects of recombinant TRAIL on apoptosis of Jurkat cells were determined by DNA fragmentation (DNA ladder) and PI staining. Changes in mitochondrial membrane potential were detected with JC-1 fluorescence. RESULTS: TRAIL inhibited the proliferation and induced internucleosomal DNA fragmentation (characteristic of apoptosis) and loss of mitochondrial membrane potential. CONCLUSION: Recombinant soluble TRAIL can be used as a therapy for cancer.