BMX activates Wnt/ß-catenin signaling pathway to promote cell proliferation and migration in breast cancer.

BACKGROUND: Breast cancer has become a dangerous killer for the female, which seriously threatened women's life, leading to huge pressures to society. The present study assessed the mechanism underlying the involvement of bone marrow tyrosine kinase on chromosome X (BMX) in breast cancer development. METHODS: The expression of BMX was examined by qPCR and immunohistochemistry. The effect of BMX on cell proliferation and migration was detected by Clone formation assay and Transwell assay. In vitro study, the correlation of BMX with Wnt/ß-catenin pathway was explored by western blot and TOP/FOP flash assay. RESULTS: In the present study, we found that BMX was up-regulated in breast cancer, which was associated with the tumor differentiation and TNM stage. Oncogenic BMX enhanced the ability of breast cancer cell proliferation and migration. Furthermore, BMX could up-regulate the protein expression levels of p-ß-catenin (Y142), p-ß-catenin(Y654) and inhibit the expression level of p-ß-catenin (S33/37), thus activating Wnt/ß-catenin pathway in MCF-7 and MDA-MB-231 cells. In addition, we revealed that BMX promoted GSK3ß phosphorylation, which suppressed the degradation of ß-catenin. CONCLUSIONS: In this study, we identified that BMX-activated Wnt/ß-catenin signaling pathway, playing an oncogenic role in breast cancer, suggesting that BMX could become a potential treatment target of breast cancer.

CREB1/Lin28/miR-638/VASP Interactive Network Drives the Development of Breast Cancer.

Breast cancer is one of the most common malignant tumors worldwide. Metastasis remains the leading cause of death in breast cancer patients. Research on the mechanism of breast cancer metastasis has become a core issue in breast cancer research. Our previous series of studies have shown that VASP, as a key oncogene, plays an important role in the development of various tumors such as breast cancer. In this study, we find that miR-638 can target to inhibit VASP expression, and Lin28 acts as an RNA-binding protein to regulate the processing of miR-638, which inhibits its maturation and promotes the expression of VASP. In addition, we also find that CREB1 acts as a transcription factor that binds to the promoter of Lin28 gene and activates the Lin28/miR-638/VASP pathway. Furthermore, CREB1 can also directly bind to the promoter of VASP, and activate VASP expression, forming a CREB/Lin28/miR-638/VASP interactive network, which plays an important role in promoting cell proliferation and migration in breast cancer. Our study explained the mechanism of CREB1/Lin28/miR-638/VASP network promoting the development of breast cancer, which further elucidated the mechanism of VASP as a key oncogene, and also provided a theoretical basis for expanding new approaches to tumor biotherapy.

Silencing lncRNA SNHG6 suppresses proliferation and invasion of breast cancer cells through miR-26a/VASP axis.

The important role of LncRNA in the development of breast cancer is attracting more and more attention. In the previous study, we found that the expression level of LncRNA SNHG6 in breast cancer tissues and cells was significantly increased, but its mechanism in the development of breast cancer was still unclear. Our study found that knockdown of SNHG6 significantly inhibited the proliferation, migration and invasion of breast cancer cells MCF-7 and MDA-MB-231 cells. Further study showed that knockdown of SNHG6 significantly inhibited the expression level of VASP. More importantly, SNHG6 and VASP both can bind directly to miR-26a, suggesting that SNHG6 could act as a ceRNA to sponge miR-26a, thereby promoting the expression of VASP, which leading to activated proliferation, migration and invasion of breast cancer cells. Taken together, this study revealed the important role of the SNHG6/miR-26a/VASP regulatory network in the development of breast cancer, and provided a reference for exploring new pathogenesis and biomarkers of breast cancer.

Antitumor effects of saikosaponin b2 on breast cancer cell proliferation and migration.

Saikosaponin b2 (SSb2) can be extracted from Bupleurum spp. roots (Radix Bupleuri), which belongs to the Umbelliferae family. The current study aimed to explore the effects of SSb2 on proliferation of breast cancer cells and to identify the mechanism by which SSb2 affects breast cancer cell migration. mRNA expression levels of STAT3 and vasodilator­stimulated phosphoprotein (VASP) were determined and increased expression was observed in 16 breast cancer tissues compared with the paracancerous tissues. MTT, wound healing, colony formation assays and western blot suggested that SSb2 inhibited MCF­7 proliferation and migration. It was further identified by western blot analysis that SSb2 treatment reduced levels of phosphorylated STAT3, VASP, matrix metallopeptidase (MMP) 2 and MMP9 in MCF­7 compared with the untreated cells. In addition, it was demonstrated that inhibition of STAT3 phosphorylation decreased VASP expression levels and induction of STAT3 phosphorylation increased VASP levels. Furthermore, it was observed that the treatment of Kunming mice with SSb2 at 30 mg/kg/day for 30 days induced no obvious changes in the liver or kidney tissues, as determined by haematoxylin and eosin staining. In conclusion, these results indicated that SSb2 may be a potential antitumor drug for the treatment of breast cancer, which acts by suppressing proliferation and migration by downregulating the STAT3 signalling pathway and inhibiting the expression of VASP, MMP2 and MMP9 expression.

Chlorotoxin targets ERα/VASP signaling pathway to combat breast cancer.

Breast cancer is one of the most common malignant tumors among women worldwide. About 70-75% of primary breast cancers belong to estrogen receptor (ER)-positive breast cancer. In the development of ER-positive breast cancer, abnormal activation of the ERα pathway plays an important role and is also a key point leading to the failure of clinical endocrine therapy. In this study, we found that the small molecule peptide chlorotoxin (CTX) can significantly inhibit the proliferation, migration and invasion of breast cancer cells. In in vitro study, CTX inhibits the expression of ERα in breast cancer cells. Further studies showed that CTX can directly bind to ERα and change the protein secondary structure of its LBD domain, thereby inhibiting the ERα signaling pathway. In addition, we also found that vasodilator stimulated phosphoprotein (VASP) is a target gene of ERα signaling pathway, and CTX can inhibit breast cancer cell proliferation, migration, and invasion through ERα/VASP signaling pathway. In in vivo study, CTX significantly inhibits growth of ER overexpressing breast tumor and, more importantly, based on the mechanism of CTX interacting with ERα, we found that CTX can target ER overexpressing breast tumors in vivo. Our study reveals a new mechanism of CTX anti-ER-positive breast cancer, which also provides an important reference for the study of CTX anti-ER-related tumors.

Upregulated IQUB promotes cell proliferation and migration via activating Akt/GSK3ß/ß-catenin signaling pathway in breast cancer.

Breast cancer was the highest incidence of tumor in women, which seriously threaten women's health. Our previous study found that the expression of IQUB (IQ motif and ubiquitin domain containing) was significantly increased in the development of breast cancer by transcriptome sequencing. However, there were no studies on the mechanism of IQUB in tumorigenesis. Further study showed that IQUB expression was significantly increased in breast cancer, which had a significantly positive correlation with pathological differentiation of breast cancer by tissue microarray analysis. Furthermore, we also discovered that IQUB overexpression could obviously promote the proliferation and migration of MCF-7 cells and increase the proportion of MCF-7 cells in S and G2/M phase in vitro study, while knockdown of IQUB caused inhibition of cell proliferation and migration in MDA-MB-231 cells and increased the proportion of MDA-MB-231 cells in G1 phase. Furthermore, IQUB overexpression or knockdown combined with treatment of Licl or MG-132 showed that IQUB activated Akt to promote GSK3ß phosphorylation, which in turn activated Wnt/ß-catenin signaling pathway in breast cancer cells. Taken together, these results indicated that upregulated IQUB promoted breast cancer cell proliferation and migration via activating Akt/GSK3ß/ß-catenin signaling pathway, which played an important part in the tumorigenesis and development of breast cancer.

Noninvasive genotyping and monitoring of anaplastic lymphoma kinase (ALK) rearranged non-small cell lung cancer by capture-based next-generation sequencing.

Noninvasive genotyping of driver genes and monitoring of tumor dynamics help make better personalized therapeutic decisions. However, neither PCR-based assays nor amplicon-based targeted sequencing can detect fusion genes like anaplastic lymphoma kinase (ALK) rearrangements in blood samples. To investigate the feasibility and performance of capture-based sequencing on ALK fusion detection, we developed a capture-based targeted sequencing panel to detect and quantify rearrangement events, along with other driver mutation variants in plasma. In this perspective study, we screened 364 patients with advanced non-small cell lung cancer (NSCLC) for ALK rearrangements, and collected blood samples from 24 of them with confirmed ALK rearrangements based on their tissue biopsies. ALK rearrangements were successfully detected in 19 of 24 patients at baseline with 79.2% (95% CI 57.9%, 92.9%) sensitivity and 100% (36/36) specificity. Among the 24 patients, we obtained longitudinal blood samples from 7 of them after either chemotherapy and/or Crizotinib treatment for disease monitoring. The by-sample detection rate of ALK rearrangements after treatment drops to 69.2% (9 of 13). In addition to detecting ALK rearrangements, we also detected 3 Crizotinib resistant mutations, ALK L1152R, ALK I1171T and ALK L1196M from patient P4. ctDNA concentration correlates with responses and disease progression, reflecting its ability as a biomarker. Our findings suggest capture-based sequencing can detect and quantify ALK rearrangements as well as other somatic mutations, including mutations mediated drug resistance, in plasma with high sensitivity, paving the way for its application in identifying driver fusion genes and monitoring tumor dynamics in the clinic.

[Construction of BAD Lentivirus Vector and Its Effect on Proliferation in A549 Cell Lines].

OBJECTIVE: To construct the recombinant lentivirus expressing vector BAD (Bcl-2-associated death protein) gene and to study its effect on A549 cell proliferation. METHODS: The BAD gene was amplified from plasmid pAV-MCMV-BAD-GFP by PCR. The purified BAD gene fragment was inserted into a lentivirus vector (pLVX-IRES-ZsGreen 1), and the insertion was identified by PCR, restriction endonuclease analysis and DNA sequencing. A549 cells were then transfected with the packaged recombinant lentivirus, and resistant cell clones were selected with flow cytometry. The expression of BAD in A549 cell lines stably transduction with a lentivirus was examined using Western blot. The effect of BAD overexpression on proliferation of A549 cells was evaluated by using CCK-8 kit. RESULTS: Restriction enzyme digestion and DNA sequencing showed that the full-length BAD gene (507 bp) had been successfully subcloned into the lentiviral vector to result in the recombinant vector pLVX-IRES-ZsGreen 1. Monoclonal cell lines BAD-A549 was produced after transfection with the recombinant lentivirus and selected with flow cytometry. Stable expression of BAD protein was verified by Western blot. In vitro, the OD value in BAD group was significantly lower than that of control groups from 120-144 h (P<0. 05). CONCLUSION: A549 cell lines stably transduced with a lentivirus expressing the BAD gene had been successfully generated. In vitro, BAD overexpression significantly inhibited A549 cells proliferation.

Diagnostic efficacy of PET and PET/CT for recurrent lung cancer: a meta-analysis.

BACKGROUND: Lung cancer is one of the most common malignant tumors in the world, and is the leading cause of cancer-related mortality. Although there are no conclusive data to support the survival benefits of early detection or early treatment for recurrence, an early and accurate diagnosis of recurrence is critical to optimize therapy. PURPOSE: To compare the diagnostic value of positron emission tomography (PET) and positron emission tomography/computed tomography (PET/CT) using fluorine-18 deoxyglucose (18FDG) with conventional imaging techniques (CITs) for the detection of lung cancer recurrence. MATERIAL AND METHODS: A meta-analysis was performed, with systematic searches conducted using PubMed and EMBASE databases (up to 31 December 2011). Pooled sensitivity, specificity, and diagnostic odds ratio (DOR) values were calculated for 1035 patients reported in 13 articles. Summary receiver-operating characteristic curves (SROC) were also generated. RESULTS: The pooled sensitivity (95% CI) for PET, PET/CT, and CITs were 0.94 (0.91-0.97), 0.90 (0.84-0.95), and 0.78 (0.71-0.84), respectively. The pooled specificity (95% CI) for PET, PET/CT, and CITs were 0.84 (0.77-0.89), 0.90 (0.87-0.93), and 0.80 (0.75-0.84), respectively. Regarding sensitivity, lower values were associated with CITs than PET (P = 0.000) and PET/CT (P = 0.005), and there was no significant difference between PET/CT and PET (P = 0.102). Regarding specificity, values for PET/CT and PET were significantly higher than for CITs (both P = 0.000), and there was no significant difference between PET/CT and PET (P = 0.273). In the SROC curves, a better diagnostic accuracy was associated with PET/CT than PET and CITs. CONCLUSION: PET/CT and PET were found to be superior modalities for the detection of recurrent lung cancer, and PET/CT was superior to PET.

FoxP3 genetic variants and risk of non-small cell lung cancer in the Chinese Han population.

CD4(+)CD25(+) regulatory T cell-mediated immunosuppression is one of the crucial mechanisms that tumor cells use to evade the immune system. The forkhead box P3 (FoxP3) gene regulates regulatory T-cell development and function and may modulate the susceptibility to non-small cell lung cancer (NSCLC). Because a single nucleotide polymorphism (SNP) within the FoxP3 gene (rs3761548 in the promoter region) is associated with susceptibility to Graves' disease, this study detected rs3761548 in a hospital-based case-control study. A total of 192 NSCLC patients and 259 healthy subjects were recruited for the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of FoxP3 SNP. The data showed that the A allele of rs3761548 significantly increased NSCLC risk (P=0.000, OR=2.32, 95%CI=1.736-3.102). The AC genotype, AA genotype, and the combined A variant genotype (AA+AC) were also associated with a higher risk of NSCLC (OR [95%CI]=2.147[1.419-3.247], 4.413[2.359-8.255], and 2.563[1.746-3.761], respectively). Moreover, a significantly higher frequency of AA+AC genotype was observed in patients with stage II NSCLC (OR, 2.053; 95%CI, 1.033-4.078). In conclusion, the data from the current study demonstrated for the first time the association of the FoxP3 SNP with a risk of developing NSCLC in the Chinese Han population.

Genetic variation in PDCD6 and susceptibility to lung cancer.

Lung cancer is the most common type of cancer and one of the leading causes of death in the world. Genetic factors play an important role in its development. PDCD6, the encoding gene for programmed cell death protein 6, may function as a tumor suppressor gene. Non-small cell lung cancer (NSCLC) contributes about 80% to newly histologically diagnosed lung cancer patients. To explore the relationship between PDCD6 and NSCLC, we examined two single nucleotide polymorphisms(rs3756712 G/T andrs4957014 G/T, both in the intron region) of the PDCD6gene.A hospital-based case-control study was carried out including 302 unrelated NSCLC patients and 306 healthy unrelated subjects. Significantly increased NSCLC risk was found to be associated with the T allele of rs4957014 (P=0.027, OR=0.760, 95%CI=0.596-0.970). The genotype and allele frequencies of rs3756712 did not shown any significant difference between NSCLC group and controls (P=0.327, OR=0.879, 95%CI=0.679- 1.137). In conclusion, we firstly demonstrated the association between the PDCD6 gene and risk of NSCLC in a Chinese Han population.

Overexpression of Bcl-2-associated death inhibits A549 cell growth in vitro and in vivo.

The importance of apoptosis during the process of inhibiting tumorigenesis has been recognized. The role of BH3-only proapoptotic protein Bcl-2-associated death (BAD) in tumor growth remains controversial. The aim of this study was to explore the role of BAD in lung cancer cells. Our study showed that expression of BAD was upregulated in A549 cells by a recombinant lentivirus overexpressing BAD. In vitro, BAD overexpression significantly inhibited A549 cell proliferation and induced apoptosis in cell proliferation and apoptosis assays, respectively. The effect of BAD on A549 cells was studied in tumor xenograft of nude mice and the results showed that the tumor volume in the experimental group was smaller than the control groups. Further, immunohistochemical technique was used to determine the cell proliferation and apoptosis status of the lung tumor xenograft cells. This demonstrated that the in vivo and in vitro results were consistent. Taken together, our results indicate that overexpression of BAD inhibits the growth of A549 cells in vitro and in vivo, through inhibiting cell proliferation and inducing apoptosis. Thus, BAD could be a potential therapeutic target.