Fluvastatin prevents lung metastasis in triple-negative breast cancer by triggering autophagy via the RhoB/PI3K/mTOR pathway.

Triple-negative breast cancer is more common among younger than older women and is associated with the poorest survival outcomes of all breast cancer types. Fluvastatin inhibits tumour progression and induces the autophagy of breast cancer cells; however, the role of autophagy in fluvastatin-induced inhibition of breast cancer metastasis is unknown. Therefore, this study aimed to determine this mechanism. The effect of fluvastatin on human hormone receptor-negative breast cancer cells was evaluated in vitro via migration and wound healing assays, western blotting, and morphological measurements, as well as in vivo using a mouse xenograft model. Chloroquine, a prophylactic medication used to prevent malaria in humans was used as an autophagy inhibitor. We found that fluvastatin administration effectively prevented the migration/invasion of triple-negative breast cancer cells, an effect that was largely dependent on the induction of autophagy. Administration of the autophagy inhibitor chloroquine prevented the fluvastatin-induced suppression of lung metastasis in the nude mouse model. Furthermore, fluvastatin increased Ras homolog family member B (RhoB) expression, and the autophagy and anti-metastatic activity induced by fluvastatin were predominantly dependent on the regulation of RhoB through the protein kinase B-mammalian target of rapamycin (Akt-mTOR) signaling pathway. These results suggest that fluvastatin inhibits the metastasis of triple-negative breast cancer cells by modulating autophagy via the up regulation of RhoB through the AKT-mTOR signaling pathway. Fluvastatin may be a promising therapeutic option for patients with triple-negative breast cancer.

The relationship between post-diagnostic statin usage and breast cancer prognosis varies by hormone receptor phenotype: a systemic review and meta-analysis.

BACKGROUND: Preclinical studies and epidemiologic data had indicated statins had antineoplastic properties in breast cancer patients. Since breast cancer treatment is based on its phenotype, it is important to explore influence of post-diagnosis statin usage on breast cancer patients with different phenotypes. METHODS: We searched the related studies between inception and August, 2019 from MEDLINE and EMBASE. A total of 7 studies with 24,541 patients were identified. Stata/SE 15.0 and Review Manager 5.3 were used to analyze data. Inconsistency index was used to estimate heterogeneity. Begg's and Egger's regression test was used to examine publication bias. RESULTS: Overall post-diagnostic statin use was associated with improved recurrence free survival (recurrence free survival (RFS); hazard ratio (HR) 0.74; 95% confidential interval (95% CI) 0.57-0.98), overall survival (overall survival (OS); HR 0.53; 95% CI 0.31-0.91) and cancer-specific survival (cancer-specific survival (CSS); and HR 0.61; 95% CI 0.41-0.91). In hormone receptor positive patients, statin use was associated with improved CSS (HR 0.74, 95% CI 0.65-0.84). No protective effect was found in either OS or RFS. In hormone receptor negative patients, statin was associated with reduced OS (HR 2.19, 95% CI 1.34-3.59) and reduced RFS, but without statistical significance. CONCLUSIONS: Post-diagnostic statin use was associated with improved RFS, OS and CSS in breast cancer patients. Subgroup analysis indicted that the benefits of statin usage varied from hormone receptor phenotype type. Prospective randomized trial with patients of different hormone receptor types might be needed to help identify which subtype of breast cancer patients would benefit from post-diagnostic statin usage.

DRR1 promotes glioblastoma cell invasion and epithelial-mesenchymal transition via regulating AKT activation.

Metastatic invasion is the primary cause of treatment failure for GBM. EMT is one of the most important events in the invasion of GBM; therefore, understanding the molecular mechanisms of EMT is crucial for the treatment of GBM. In this study, high expression of DRR1 was identified to correlate with a shorter median overall and relapse-free survival. Loss-of-function assays using shDRR1 weakened the invasive potential of the GBM cell lines through regulation of EMT-markers. The expressions of p-AKT were significantly decreased after DRR-depletion in SHG44 and U373 cells. Moreover, the invasion was inhibited by the AKT inhibitor, MK-2206. The expression of Vimentin, N-cadherin, MMP-7, snail and slug was significantly inhibited by MK-2206, while the expression of E-cadherin was upregulated. Our results provide the first evidence that DRR1 is involved in GBM invasion and progression possibly through the induction of EMT activation by phosphorylation of AKT.

Manganese Superoxide Dismutase Gene-Modified Mesenchymal Stem Cells Attenuate Acute Radiation-Induced Lung Injury.

Radiation-induced lung injury (RILI) is a major clinical complication for radiotherapy in thoracic tumors. An immediate effect of lung irradiation is the generation of reactive oxygen that can produce oxidative damage to DNA, lipids, and proteins resulting in lung cell injury or death. Currently, the medical management of RILI remains supportive. Therefore, there is an urgent need for the development of countermeasures. The present study aimed to evaluate the protective effect of manganese superoxide dismutase (MnSOD) gene-modified mesenchymal stem cells (MSCs) to facilitate the improved recovery of RILI. Here, nonobese diabetic/severe combined immunodeficiency mice received a 13 Gy dose of whole-thorax irradiation, and were then transfused intravenously with MnSOD-MSCs and monitored for 30 days. Lung histopathologic analysis, plasma levels of inflammatory cytokines (interleukin [IL]-1, IL-6, IL-10, and tumor necrosis factor-α), profibrotic factor transforming growth factor-ß1, and the oxidative stress factor (hydroxyproline) were evaluated after MnSOD-MSC transplant. Apoptotic rates were evaluated by terminal deoxynucleotidyl transferase-mediated nick-end labeling immunohistochemical method. Colonization and differentiation of MnSOD-MSCs in the irradiated lung were analyzed by immunofluorescence staining. Consequently, systemic administration of MnSOD-MSCs significantly attenuated lung inflammation, ameliorated lung damage, and protected the lung cells from apoptosis. MnSOD-MSCs could differentiate into epithelial-like cells in vivo. MnSOD-MSCs were effective in modulating RILI in mice and had great potential for accelerating from bench to bedside.

Cullin-1 promotes cell proliferation in human breast cancer and is related to diabetes.

AIM: Breast carcinoma (BCA) and diabetes mellitus (DM) are two major health problems in women and the general population. Cullin-1 is reported to be an important tumor-related protein involved in cell-cycle progression, signal transduction and transcription. The aim of this work is to investigate the role of Cullin-1 in the development of BCA and to find potential relationships between Cullin-1 and diabetes in BCA patients. METHODS: To evaluate the function of Cullin-1, we entered 168 patients with primary invasive BCA in this study. Pairs of BCA tissues and adjacent noncancerous tissues from these patients were collected between 2006 and 2008. We used immunohistochemistry to analyze the correlation between Cullin-1 expression and clinicopathological variables and patient survival. In addition, we investigated the role of Cullin-1 in BCA cell proliferation. RESULTS: Cullin-1 expression was upregulated in BCA tissues. Enhanced immunoreactivity for Cullin-1 in BCA tissues was inversely correlated with overall survival and disease-free survival, which suggested a poor prognosis in BCA patients. Strong expression of Cullin-1 was more frequently observed in patients with estrogen receptor negativity and HER2 positivity. We also found that Cullin-1 expression was increased in BCA patients with a previous diagnosis of diabetes. CONCLUSIONS: Our results demonstrate that increased Cullin-1 expression is significantly correlated with poor prognosis in patients with BCA. Cullin-1 might regulate BCA cell proliferation through the ubiquitin-proteasome system. Thus, Cullin-1 might be an important marker and a therapeutic target in BCA.

Estrogen enhances the bone regeneration potential of periodontal ligament stem cells derived from osteoporotic rats and seeded on nano-hydroxyapatite/collagen/poly(L-lactide).

This study investigated the effects of estrogen on the bone regeneration potential of periodontal ligament stem cells (PDLSCs) derived from osteoporotic rats and seeded on a collagen-based composite scaffold [nano-hydroxyapatite/collagen/poly(L-lactide) (nHAC/PLA)]. For this purpose, 48 healthy 3­month-old Sprague-Dawley female rats were divided into 2 groups as follows: the bilaterally ovariectomized (OVX) rats and sham­operated rats. The PDLSCs were isolated at 3 months after surgery (by which time postmenopausal osteoporosis had developed). The effects of estrogen on the characteristics of these cells seeded in a culture plate and of the cells seeded on nHAC/PLA were then investigated. The PDLSC + nHAC/PLA constructs were implanted subcutaneously into the backs of severe combined immunodeficient (SCID) mice for 12 weeks in order to examine the role of estrogen in the bone formation ability of PDLSCs derived from osteoporotic rats. The results from methyl thiazolyl tetrazolium (MTT) assay revealed that the proliferation of the cells derived from the rats in the OVX group was significantly higher than that of the cells derived from the rats in the sham-operated group at the stage of logarithmic growth. The staining intensity of alkaline phosphatase (ALP) and the mineralization of the cells derived from the rats in the OVX group was significantly weaker than that of the cells from the rats in the sham-operated group. When the PDLSCs were seeded on nHAC/PLA, ALP activity, osteocalcin (OCN) secretion, mineral formation and the mRNA expression levels of ALP, OCN, estrogen receptor (ER)α and ERß in the cells derived from the rats in the OVX group were markedly decreased. Treatment with 17ß-estradiol (E2) significantly weakened the proliferative ability of the cells derived from the OVX group rats, and enhanced their osteogenic differentiation ability and the mRNA expression levels of ALP, OCN, ERα and ERß. When the constructs were implanted into the backs of SCID mice for 12 weeks, the results of histological analysis indicated that the constructs derived from the OVX group rats had a few newly formed bones and osteoids; however, a great number of newly formed bones and osteoids were present in the ones from the sham-operated group and the OVX + E2 group rats. Our findings further indicate that estrogen deficiency impairs the osteogenic differentiation potential of PDLSCs, and that ER plays an important role in the bone regeneration ability of PDLSCs. Estrogen enhances the bone regeneration potential of PDLSCs derived from osteoporotic rats and seeded on nHAC/PLA. This study may provide insight into the clinical management of periodontal bone tissue repair in postmenopausal women with the use of estrogen-mediated PDLSCs seeded on nHAC/PLA.

Risk of a lamotrigine-related skin rash: current meta-analysis and postmarketing cohort analysis.

PURPOSE: We systematically reviewed studies to provide current evidence on the incidence and risk of skin rash in patients with LTG therapy. METHODS: PubMed and Scopus databases, up to 15 March 2014 were searched to identify relevant studies. Eligible studies included prospective studies, retrospective studies and postmarketing reports, which included data of skin rash in patients with LTG therapy. RESULTS: Forty-one articles met the entry criteria. A total of 4447 patients with LTG therapy from 26 prospective studies, 2977 patients from 8 retrospective studies, and 26,126 patients from 5/7 postmarketing reports were included. The overall incidence of skin rash with LTG therapy was 9.98% (444/4447) from prospective studies, 7.19% (214/2977) from retrospective studies, and 2.09% (547/26,126) from postmarketing reports. A meta-analysis of the risk of skin rash in 21 prospective studies, did not show a significant difference between patients with LTG and other drugs, including placebo, other ADEs or lithium (OR 0.99-2.41). In 6 respective studies, there was a significantly higher OR in patients with LTG compared with those with non-aromatic AEDs. However, there was no significant difference in rash risk between patients with LTG and aromatic AEDs. CONCLUSIONS: Our study showed that LTG significantly increased the risk of developing a skin rash compared to non-aromatic AEDs. Our results support the need for large prospective population-based studies and clinical trials to determine whether LTG increases the risk of developing a skin rash than compared to other drugs.

Mechanisms of protection against diabetes-induced impairment of endothelium-dependent vasorelaxation by Tanshinone IIA.

BACKGROUND: Impairment of endothelium-dependent vasorelaxation has been suggested to play a principle role of endothelial dysfunction in the development of cardiovascular complications of diabetes. Recent studies have demonstrated a protective effect of Tanshinone IIA (Tan) on endothelial nitric oxide synthase (eNOS)-NO pathway. However, its role in endothelium-dependent vasorelaxation in diabetes and precise mechanisms remain elusive. METHODS: Sprague-Dawley rats were injected intraperitoneally with streptozotocin (STZ) to induce diabetes and then administered orally with Tan for 2 weeks. For the in vitro study, human umbilical vein endothelial cells (HUVECs) were co-incubated with Tan and high glucose for 48 h. RESULTS: eNOS expression and NO generation were significantly decreased in diabetic rats. These decreases were accompanied by an impairment of endothelium-dependent relaxation. Administration of Tan ameliorated the aberrant changes in eNOS expression, NO generation and endothelium-dependent relaxation in diabetic rats. Expectedly, Tan also inhibited high glucose-induced decrease of eNOS expression and NO generation in a concentration-dependent manner in HUVECs. Mechanistically, high glucose attenuated eNOS transcriptional activity through inhibiting the binding activity and nuclear translocation of Sp1 and AP-1. However, Tan did not prevent these effects. At post-transcriptional level, Tan increased eNOS expression and activity through multiple mechanisms including regulation of mRNA and protein half-life, degradation, coupling and serine 1177 phosphorylation. Rather than affecting protein phosphatase 2A (PP2A) expression and activity, Tan markedly inhibited the translocation of PP2A-A from cytosol to membrane and subsequently impaired PP2A-A/eNOS interaction, leading to prevent eNOS dephosphorylation. All these alterations underlie the protective role of Tan on eNOS expression following high glucose stimulation. CONCLUSIONS: Our data demonstrate that high glucose decreases eNOS expression initiating at a transcriptional level, whereas Tan prevents such effect through multiple ways of post-transcriptional mechanism. GENERAL SIGNIFICANCE: Our work provided novel mechanisms for Tan in regulating vasorelaxation and may help to better understand the cardiovascular protective action of Tan.

Inhibition of autophagy enhances the cytotoxic effect of PA-MSHA in breast cancer.

BACKGROUND: PA-MSHA, a genetically engineered Pseudomonas aeruginosa (PA) strain, is currently under investigation as a new anti-cancer drug. It can induce cell cycle arrest and apoptosis in different human cancer cells, including hormone receptor negative breast cancer cells. However, the underlying mechanism of tumor lethality mediated by PA-MSHA remains to be fully investigated. METHODS: The effect of PA-MSHA on human hormone receptor negative breast cancer cells was analyzed by morphological measurement, western blot, cell proliferation assay and mouse xenograft model. RESULTS: PA-MSHA was found to induce endoplasmic reticulum (ER) stress in breast cancer cell lines through the IRE1 signaling pathway. Inhibiting autophagy potentiated the cytotoxic effect of PA-MSHA while treating breast cancer cell lines. In mouse xenograft model, PA-MSHA produced more pronounced tumor suppression in mice inoculated with IRE1 gene knockdown. MDA-MB-231HM cells. CONCLUSIONS: These findings demonstrated inhibiting autophagy together with PA-MSHA might be a promising therapeutic strategy in treating hormone receptor negative breast cancer cells.

Effect of genetic variants in two chemokine decoy receptor genes, DARC and CCBP2, on metastatic potential of breast cancer.

The inhibitory effect of two chemokine decoy receptors (CDRs), DARC and D6, on breast cancer metastasis is mainly due to their ability to sequester pro-malignant chemokines. We hypothesized that genetic variants in the DARC and CCBP2 (encoding D6) genes may be associated with breast cancer progression. In the present study, we evaluated the genetic contributions of DARC and CCBP2 to metastatic potential, indicated by lymph node metastasis (LNM). Ten single-nucleotide polymorphisms (SNPs) (potentially functional SNPs and block-based tagging SNPs) in DARC and CCBP2 were genotyped in 785 breast cancer patients who had negative lymph nodes and 678 patients with positive lymph nodes. Two non-synonymous SNPs, rs12075 (G42D) in DARC and rs2228468 (S373Y) in CCBP2, were observed to be associated with LNM in univariate analysis and remained significant after adjustment for conventional clinical risk factors, with odds ratios (ORs) of 0.54 (95% confidence interval [CI], 0.37 to 0.79) and 0.78 (95% CI, 0.62 to 0.98), respectively. Additional functional experiments revealed that both of these significant SNPs could affect metastasis of breast cancer in xenograft models by differentially altering the chemokine sequestration ability of their corresponding proteins. Furthermore, heterozygous GD genotype of G42D on human erythrocytes had a significantly stronger chemokine sequestration ability than homozygous GG of G42D ex vivo. Our data suggest that the genetic variants in the CDR genes are probably associated with the varied metastatic potential of breast cancer. The underlying mechanism, though it needs to be further investigated, may be that CDR variants could affect the chemokine sequestration ability of CDR proteins.

Expression of dickkopf-1 and beta-catenin related to the prognosis of breast cancer patients with triple negative phenotype.

BACKGROUND AND AIM: We investigated the prognostic importance of dickkopf-1(DKK1) and beta-catenin expression in triple negative breast cancers. METHODS: The expression of DKK1 and beta-catenin was evaluated in breast cell lines using RT-PCR and western blot. Immunohistochemistry was used to characterize the expression pattern of DKK1 and beta-catenin in 85 triple negative breast cancers and prognostic significance was assessed by Kaplan-Meier analysis and Cox proportional hazards regression modeling. RESULTS: The expression of DKK1 was confirmed in hormone-resistant breast cell lines MDA-MB-231, MDA-MB-231-HM and MDA-MB-435. Expression of DKK1 in triple negative breast cancers correlated with cytoplasmic/nuclear beta-catenin (p = 0.000). Elevated expression of DKK1 and cytoplasmic/nuclear beta-catenin in triple negative cancers indicate poor outcome of patients. DKK1 was also a prognostic factor for patients with earlier stage or no lymph node metastasis. CONCLUSION: DKK1 together with beta-catenin might be important prognostic factors in triple negative breast carcinoma. DKK1 might be a valuable biomarker in predicting the prognosis of patients with earlier stage or no lymph node metastasis. It is possible that through further understanding of the role of Wnt/beta-catenin pathway activation, beta-catenin would be a potential therapeutic target for the triple negative breast cancer.

Current evidence on the relationship between polymorphisms in the COX-2 gene and breast cancer risk: a meta-analysis.

The association between single-nucleotide polymorphisms (SNPs) in the COX-2 gene and breast cancer risk is still ambiguous. We here try to derive a more precise estimation of the relationship by performing a meta-analysis based on currently available evidence from literature. More than 15 SNPs have been studied, and the most studied genetic variants were rs5275, rs5277, and rs20417. Crude odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association between each polymorphism and breast cancer risk under the codominant model, dominant model, and recessive model, respectively (nine studies with 6,968 cases and 9,126 controls for rs5275; three studies with 2,901 cases and 3,463 controls for rs20417; two studies with 5,551 cases and 6,208 controls for rs5277). No overall significant associations were observed in single-locus analysis between the three polymorphisms of COX-2 and breast cancer risk, though a borderline significant increased risk of breast cancer was detected with rs5277 in a recessive model (OR: 1.217, 95% CI: 0.958-1.547, P = 0.107). The results were not changed when studies were stratified by ethnicity. In conclusion, the present meta-analysis suggests that none of the most studied three SNPs (rs5275, rs20417, and rs5277) in the COX-2 gene is a conspicuous low-penetrant risk factor for developing breast cancer. There is a need for further large studies into the role of these polymorphisms (especially rs5277) and other potentially functional polymorphisms/haplotypes in the COX-2 gene as breast cancer risk modifiers.