1-Monopalmitin promotes lung cancer cells apoptosis through PI3K/Akt pathway in vitro.

Lung cancer is the leading cause of cancer-related death worldwide and non-small cell lung cancer (NSCLC) represents 85%. Mougeotia nummuloides and Spirulina major have been reported to possess anticancer properties. 1-Monopalmitin (1-Mono) is the principle active constituent in these natural plants. It is debating whether 1-Mono exerts antitumor effects. Therefore, we explored the role of 1-Mono in lung cancer in vitro. Results showed that 1-Mono significantly inhibited A549 and SPC-A1 cell proliferation, induced G2/M arrest and caspase-dependent apoptosis. Moreover, it suppressed the protein expression of inhibitors of apoptosis proteins (IAPs). It was further demonstrated that 1-Mono activated the PI3K/Akt pathway, suppression of PI3K/Akt activities with LY294002 and Wortmannin partially attenuated 1-Mono-mediated anticancer activities, indicating that 1-Mono-induced antitumor effects is dependent on PI3K/Akt pathway. 1-Mono induced cytoprotective autophagy since autophagy inhibitor Chloroquine dramatically enhanced 1-Mono-induced cytotoxicity. In summary, our results showed 1-Mono kills lung cancer through PI3K/Akt pathway, providing novel options for lung cancer administration.

Loss of TDP43 inhibits progression of triple-negative breast cancer in coordination with SRSF3.

Aberrant alternative splicing has been highlighted as a potential hallmark of cancer. Here, we identify TDP43 (TAR DNA-binding protein 43) as an important splicing regulator responsible for the unique splicing profile in triple-negative breast cancer (TNBC). Clinical data demonstrate that TDP43 is highly expressed in TNBC with poor prognosis. Knockdown of TDP43 inhibits tumor progression, including proliferation and metastasis, and overexpression of TDP43 promotes proliferation and malignancy of mammary epithelial cells. Deep sequencing analysis and functional experiments indicate that TDP43 alters most splicing events with splicing factor SRSF3 (serine/arginine-rich splicing factor 3), in the regulation of TNBC progression. The TDP43/SRSF3 complex controls specific splicing events, including downstream genes PAR3 and NUMB The effect of reduced metastasis and proliferation upon the knockdown of TDP43 or SRSF3 is mediated by the splicing regulation of PAR3 and NUMB exon 12, respectively. The TDP43/SRSF3 complex and downstream PAR3 isoform are potential therapeutic targets for TNBC.

Chromosome-wide gene dosage rebalance may benefit tumor progression.

The high-risk of tumor initiation in patients with Turner syndrome (TS) characterized by X chromosome monosomy in women has been well established and aneuploidy, defined as an abnormal number of chromosomes, is a common feature in human cancer. However, the underlying mechanisms of X chromosome aneuploidy promoting tumorigenesis remain obscure. We propose that chromosome-wide gene dosage imbalance (CDI) may serve as an important mechanism. Here, we assess the relative expression ratios of X chromosome and autosomes (expression ratios of X:AA) between tumor samples and adjacent normal samples across 16 tumor types using expression datasets from The Cancer Genome Atlas (TCGA) project. Our results show that the expression ratios of X:AA in tumor samples are frequently rebalanced to a lower level compared to those in adjacent normal samples, which is termed chromosome-wide gene dosage rebalance (CDR) thereafter. Gene ontology (GO) analysis of differentially expression genes from X chromosome reveals that downregulation of multicellularity-related genes and upregulation of unicellularity-related genes in tumors form a distinctive feature and enrichment analysis shows that downregulated genes are enriched in tumor suppressor genes, which indicate that CDR benefits tumor progression. Further experimental results prove that disturbance of X chromosome expression by knocking down of XIST in breast cancer cells, which functions in initiation phase of X chromosome inactivation (XCI), inhibits tumor progression. Our results demonstrate that the prevalent CDRs across tumor types serve as an important mechanism in promoting tumor progression, which partially explains the high risk of tumor in patients with TS and also provides a new cancer therapy from the CDR perspective.

Dexmedetomidine expands monocytic myeloid-derived suppressor cells and promotes tumour metastasis after lung cancer surgery.

BACKGROUND: Dexmedetomidine (DEX) has been reported to promote tumour metastases. However the underlying mechanisms remain unclear. The purpose of this study was to investigate whether DEX promotes tumour metastasis by inducing myeloid-derived suppressor cells (MDSC) in the context of surgery. METHODS: DEX was given to lung cancer patients and its effects on expansion of monocytic MDSC (M-MDSC) were studied in the context of surgery. Spontaneous tumour metastasis was induced in C57BL/6 mice and the effects of DEX on M-MDSC expansion and metastasis formation were assessed. RESULTS: DEX increased CD11b+CD33+HLA-DR-CD14+ M-MDSC in lung cancer patients after thoractomy. DEX-induced M-MDSC, in addition to have immunosuppressive activity, were more efficient in producing VEGF. Expansion of M-MDSC by DEX involved α2-adrenergic receptor. Using an experimental tumour metastasis mouse model, we demonstrated that the numbers of metastases on lung surface and CD11b+Ly6ChighLy6G- M-MDSC during postoperative period were enhanced in DEX-treated mice. Promotion of tumour metastasis by DEX-induced M-MDSC involved VEGF, a key factor for tumour angiogenesis. CONCLUSIONS: DEX induces the proliferation of M-MDSC during postoperative period in lung cancer patients and this cell population is qualified with potent proangiogenic ability. Treatment of mice with DEX expands M-MDSC and promotes tumour metastasis through the increasing production of VEGF.

Hsa_circ_0046264 up-regulated BRCA2 to suppress lung cancer through targeting hsa-miR-1245.

OBJECTIVE: Lung cancer had been leading mounts of deaths worldwide. Advances in genes microarray had helped human further understand genes and identify novel circular RNAs. This study aimed at investigating the biological functions and molecular mechanisms of hsa_circ_0046264 in lung cancer which may be helpful in lung cancer early diagnosis and clinical treatment. METHODS: Gene microarray data screened the differential gene of hsa_circ_0046264 and its downstream genes were found by bioinformatics analysis and verified by luciferase reporter assay. QRT-PCR and Western blot was used to detect the RNA and protein levels respectively. RNase R digestion confirmed the existences of circular RNA. Cell viability, invasion and apoptosis were determined by MTT assay, flow cytometry and DNA damage assay. Tumor formation in nude mice and immunohistochemistry proved the functions of hsa_circ_0046264 in vivo. RESULTS: Hsa_circ_0046264 and BRCA2 were down-regulated in lung cancer tissues while miR-1245 was up-regulated. Hsa_circ_0046264 induced apoptosis but inhibited proliferation and invasion of lung cancer cells through targeting miR-1245 to up-regulate BRCA2. Hsa_circ_0046264 inhibited the tumor growth in vivo. CONCLUSION: Hsa_circ_0046264 was a tumor suppressor in lung cancer. Overexpression of hsa_circ_0046264 could up-regulate BRCA2 expression through down-regulating of miR-1245.

The influence of myeloid-derived suppressor cells on angiogenesis and tumor growth after cancer surgery.

While myeloid-derived suppressor cells (MDSCs) have been reported to participate in the promotion of angiogenesis and tumor growth, little is known about their presence and function during perioperative period. Here, we demonstrated that human MDSCs expressing CD11b(+), CD33(+) and HLA-DR(-) significantly increased in lung cancer patients after thoracotomy. CD11b(+) CD33(+) HLA-DR(-) MDSCs isolated 24 hr after surgery from lung cancer patients were more efficient in promoting angiogenesis and tumor growth than MDSCs isolated before surgical operation in allograft tumor model. In addition, CD11b(+) CD33(+) HLA-DR(-) MDSCs produced high levels of MMP-9. Using an experimental lung metastasis mouse model, we demonstrated that the numbers of metastases on lung surface and Gr-1(+) CD11b(+) MDSCs at postoperative period were enhanced in proportion to the degree of surgical manipulation. We also examined that syngeneic bone marrow mesenchymal stem cells (BMSCs) significantly inhibited the induction and proliferation of Gr-1(+) CD11b(+) MDSCs and further prevented lung metastasis formation in the mice undergoing laparotomy. Taken together, our results suggest that postoperatively induced MDSCs were qualified with potent proangiogenic and tumor-promotive ability and this cell population should be considered as a target for preventing postoperative tumor metastasis.

S. glabra exerts anti-lung cancer effects by inducing ferroptosis and anticancer immunity.

BACKGROUND: Sarcandra glabra (S. glabra), a traditional Chinese medicine (TCM), has demonstrated significant anticancer activity; however, the underlying mechanisms have not yet been fully elucidated. PURPOSE: This study aimed to investigate the effects of S. glabra on lung cancer and to explore its underlying mechanisms. METHODS: The chemical profile of S. glabra was analyzed via ultrahigh-performance liquid chromatography coupled with mass spectrometry (UPLC-MS). The effects of S. glabra on the viability, proliferation, apoptosis, migration, and invasion of lung cancer cells were assessed via CCK8, colony formation, flow cytometry, scratch, and Transwell assays. In vivo anticancer activity was evaluated in an LLC mouse model. Proteomic analysis was performed to identify key molecules and pathways in S. glabra-treated LLC cells. The expression of ferroptotic proteins and associated cellular events were examined via western blotting, ROS production, iron accumulation, and lipid peroxidation assays. Immune modulation in tumor-bearing mice was evaluated by detecting immune cells and cytokines in the peripheral blood and tumor tissue. RESULTS: Our analysis quantified 1997 chemical markers in S. glabra aqueous extracts. S. glabra inhibited the viability and proliferation of lung cancer cells and induced cell cycle arrest and apoptosis. Scratch and Transwell assays demonstrated that S. glabra suppressed the migration and invasion of lung cancer cells. Oral administration of S. glabra significantly inhibited tumor growth in LLC tumor-bearing mice. Proteomic analysis revealed that S. glabra upregulated the expression of the HMOX1 protein and activated the ferroptosis pathway. Consistent with these findings, we found that S. glabra triggered ferroptosis in lung cancer cells, as evidenced by the upregulation of HMOX1, downregulation of GPX4 and ferritin light chain proteins, iron accumulation, increased ROS production, and lipid peroxidation. Furthermore, S. glabra demonstrated immunostimulatory properties in LLC tumor-bearing mice, leading to increased populations of immune cells (NK cells) and elevated cytokine levels (IL-2). CONCLUSION: This study is the first to demonstrate that S. glabra induces ferroptosis in lung cancer cells by regulating HMOX1, GPX4, and FTL. These findings provide a robust scientific basis for the clinical application of S. glabra in lung cancer treatment.

Proteogenomic analysis of air-pollution-associated lung cancer reveals prevention and therapeutic opportunities.

Air pollution significantly impacts lung cancer progression, but there is a lack of a comprehensive molecular characterization of clinical samples associated with air pollution. Here, we performed a proteogenomic analysis of lung adenocarcinoma (LUAD) in 169 female never-smokers from the Xuanwei area (XWLC cohort), where coal smoke is the primary contributor to the high lung cancer incidence. Genomic mutation analysis revealed XWLC as a distinct subtype of LUAD separate from cases associated with smoking or endogenous factors. Mutational signature analysis suggested that Benzo[a]pyrene (BaP) is the major risk factor in XWLC. The BaP-induced mutation hotspot, EGFR-G719X, was present in 20% of XWLC which endowed XWLC with elevated MAPK pathway activations and worse outcomes compared to common EGFR mutations. Multi-omics clustering of XWLC identified four clinically relevant subtypes. These subgroups exhibited distinct features in biological processes, genetic alterations, metabolism demands, immune landscape, and radiomic features. Finally, MAD1 and TPRN were identified as novel potential therapeutic targets in XWLC. Our study provides a valuable resource for researchers and clinicians to explore prevention and treatment strategies for air-pollution-associated lung cancers.

Metabolomics analysis of the potential mechanism of Yi-Guan-Jian decoction to reverse bone loss in glucocorticoid-induced osteoporosis.

BACKGROUND: Glucocorticoid-induced osteoporosis (GIOP) is a disease in which long-term use of glucocorticoid causes bone loss, deterioration of bone microstructure and fracture. Currently, clinical drugs targeting this disease have certain side effects. There is still a need to find effective drugs with fewer side effects. The theory of traditional Chinese medicine suggests that YGJ has therapeutic effect on GIOP, but it has not been explained. Therefore, this study aims to explore the protective effect of YGJ on GIOP mouse models and elucidate the underlying mechanism through LC-MS-based metabolomics analysis. METHODS: The general condition of 8 week age male C57BL/6J mice was recorded after 8 weeks of treatment with dexamethasone (DEX) and YGJ. Bone-related parameters and bone morphology were determined by Micro-CT. HE staining was used to observe the pathological changes of bone tissue. Serum levels of bone metabolism markers were detected by ELISA. Liver metabolomics analysis was conducted to search for the significant markers of anti-GIOP of YGJ and the metabolic pathway affecting it. RESULTS: After treatment, YGJ significantly reversed the weight loss caused by DEX; increase the number of bone trabecular in ROI region, significantly improve the bone-related parameters of GIOP mice, and increase the levels of alkaline phosphatase and osteocalcin. In the study of metabolic mechanism, YGJ reversed 24 potential markers in GIOP mice. These included cortisol, 3-hydroxybutyric acid, taurine, esculin and uric acid, which are closely associated with osteoporosis. Topological analysis results showed that YGJ had the most significant effect on taurine and hypotaurine metabolism, with - log10 (P) > 2.0 and Impact > 0.4. CONCLUSIONS: Yi-Guan-Jian decoction can increase bone density and improve bone microstructure by regulating the levels of alkaline phosphatase and osteocalcin and reverse bone loss in GIOP mouse model. The underlying metabolic mechanism may be related to taurine and hypotaurine metabolic pathway.

Transient directing group enabled Pd-catalyzed C-H oxygenation of benzaldehydes and benzylic amines.

We report a general protocol for ortho-C-H fluoroalkoxylation of benzaldehydes and benzylic amines utilizing an inexpensive amino amide as a transient directing group. In the presence of an electrophilic fluorinating bystanding oxidant and fluorinated alcohols, a wide range of benzaldehydes and benzylic amines could be oxygenated selectively at the ortho positions to afford fluoroalkyl aryl ethers. This elegant approach would provide appealing strategies for synthesis of drug molecules and natural products.

EGFR and ERK activation resists flavonoid quercetin-induced anticancer activities in human cervical cancer cells in vitro.

In the present study, due to the complex and numerous targets of Sarcandrae Herb (also known as Zhong Jie Feng), network pharmacology was performed to analyze its therapeutic effect on 2 cervical cancer cell lines, which could assist with the development of novel therapies. The results suggested that the natural flavonoid quercetin (Que), the effective antitumor ingredient in SH, which is widely present in a variety of plants, may depend on the target, EGFR. Previous studies have shown that EGFR serves a crucial role in the occurrence and development of cervical cancer, but its downstream molecules and regulatory mechanisms remain unknown. The anti-cervical cancer cell properties of Que, which are present in ubiquitous plants, were examined in vitro to identify the association between Que and its underlying pathway using MTT assays, flow cytometry, western blot analysis and Transwell assays. It was found that Que reduced cervical cancer cell viability, promoted G2/M phase cell cycle arrest and cell apoptosis, as well as inhibited cell migration and invasion. The Tyr1068 phosphorylation site of EGFR and the corresponding ERK target were also examined and the 2 kinases were markedly activated by Que. Furthermore, the EGFR inhibitor, afatinib and the ERK inhibitor, U0126 blocked the increase of EGFR and ERK phosphorylation, and resulted in a notable enhancement of apoptosis and cell cycle arrest. Therefore, to the best of our knowledge, the current results provided the first evidence that EGFR and ERK activation induced by Que could resist Que-induced anticancer activities. On this basis, the present study determined the role of EGFR and the underlying signaling pathways involved in the anti-cervical cancer malignant behavior induced by Que and identified the negative regulatory association.

Coculturing dendritic cells with zoledronate acid efficiently enhance the anti-tumor effects of cytokine-induced killer cells.

INTRODUCTION: Dendritic cells (DCs) have greater stimulating activity on innate and adaptive immunity following short-term sensitization with zoledronate acid (DCs(Zol)). We identified the phenotype, cytotoxicity, and mechanisms of killing of cytokine-induced killer (CIK) cells which were cocultured with DCs(Zol). METHODS: Adherent and nonadherent cells of peripheral blood mononuclear cell from myeloma patients were incubated for DCs and CIK cells. Then, the CIK cells were cocultured with DCs(Zol) (DCs(Zol)-CIK). Expression of markers for DCs(Zol)-CIK cells was measured using flow cytometry. Cytotoxicity was evaluated by against human myeloma cell lines and mechanisms of killing were tested by selectively blocking NKG2D receptor. The anti-tumor activity of these effector cells was further evaluated using a nude mice tumor model. RESULTS: gammadelta TCR expression of CIK cells significantly increased after coculture with immature or mature DCs(Zol) (iDCs/mDCs(Zol)-CIK) and these cells aggressively lysed myeloma cells compared with mDCs-CIK and zoledronate acid pulsed CIK cells (CIK(Zol); 50.8 +/- 7.9% and 48.2 +/- 4.7% versus 31.9 +/- 5.1% and 20.5 +/- 3.6%, effector versus target ratio was 60:1). Both alphabeta T and gammadelta T cells in the iDCs(Zol)-CIK cells performed the majority of lysis. The iDCs/mDCs(Zol)-CIK cells greatly increased NKG2D expression compared with mDCs-CIK and CIK(Zol) during culture (71.5 +/- 11.3% and 67.7 +/- 9.3% versus 51.3 +/- 6.2% and 47.1 +/- 5.7%). iDCs(Zol)-CIK cell-mediated lysis dropped 69.21% when the NKG2D receptor was blocked and the cytotoxicity correlated with NKG2D ligand-MICA expression on the target cells. In a human myeloma bearing nude mice model, iDCs(Zol)-CIK and mDCs(Zol)-CIK cells treatment groups obtained 75% and 62.5% long-term survival (>120 days) respectively, as compared with none of the control animals or 37.5% treated with mDCs-CIK cells. CONCLUSION: Large numbers of CIK cells with greater anti-tumor activities are rapidly generated by Zol-treated iDCs/mDCs. This strategy is worthy of further investigation to improve adoptive cell therapy against tumors.

A simple and effective method for cancer immunotherapy by inactivated allogeneic leukocytes infusion.

Allogeneic mixed leukocytes reaction has been reported to activate vast numbers of T lymphocytes and produce large amounts of type 1 cytokines that are linked to an initiation of antitumor immunity. Using poor immunogeneic B16-F10 and Lewis lung carcinoma (LLC) tumor model, we evaluated the effects of inactivated allogeneic leukocytes infusion (ALI) on the generation of antitumor immune response, as well as its effect on the primary and metastatic tumor. Allogeneic response promoted the generation of both specific and nonspecific antitumor immunity in an in vitro mixed lymphocytes-tumor cell culture system. Introveinous infusion of mitotically inactivated allogeneic leukocytes resulted in increased type-1 cytokines (including IL-2 and IFN-gamma) release, proliferation of various lymphocyte subsets, and generation of both specific and nonspecific antitumor immune response. As a result of such immune response, ALI caused a delayed tumor growth and a prolonged survival in established B16-F10 melanoma model. In LLC pulmonary spontaneous metastases model, ALI treatment significantly reduced postoperative tumor metastasis as the lung weights were far smaller than control group (0.16 vs. 0.34 g). Furthermore, after primary tumor resection and ALI treatment, 62.5% mice obtained long-term survival (>120 days) and there were no tumor growths in these mice when they were rechallenged with the same tumor. These experiments demonstrate that inactivated ALI could activate innate and adoptive antitumor immune response. It would be a simple, effective and secured method for cancer immunotherapy.

Enhanced anti-tumor immunity generated by Rituximab-coated tumor cell vaccine.

Rituximab is a chimeric monoclonal antibody against CD20, and has been used to treat malignant tumors derived from B cell. We designed a tumor cell vaccine modified by Rituximab, and evaluated anti-tumor effect in human CD20 gene transfected mice tumor model in vivo, and in human CTLs induction by mixed lymphocyte tumor cell culture in vitro. The results demonstrated that the Rituximab-coated tumor cell vaccine had a significant therapeutic effect against tumor pulmonary metastasis formation. Antibody depletion experiments showed CD8+ T Cells were essential for the anti-tumor effect but not NK cells. Capture rate of tumor cells by DCs, which were detected by flow cytometry, was increased by adding Rituximab. The tumor specific cytolysis could be induced by Rituximab-coated tumor cell in human in vitro assay. This therapeutic strategy provides a simple way to potentialize CTLs function to combat cancer and may promote more clinical consideration in immunotherapy for tumors. Rituximab-coated tumor cell vaccine also expanded the clinical Rituximab applications.

Bone marrow mesenchymal stem cells tune the differentiation of myeloid-derived suppressor cells in bleomycin-induced lung injury.

BACKGROUND: Bone marrow mesenchymal stem cells (BMSC) transfer has been attempted as a therapeutic strategy in experimental lung injury and fibrosis. Reduction of neutrophilic infiltration is one of the mechanisms involved in this effect. However, the mechanisms by which BMSC modulate neutrophil remains unknown. METHODS AND RESULTS: Exposure of mice to bleomycin (BLM) resulted in significant accumulation of cells that express neutrophilic markers Gr-1HighCD11b+Ly-6GHighF4/80-CD115-CD49d-. These cells lacked immunosuppressive activity and could not be defined as myeloid-derived suppressor cells (MDSC). When BMSC were administrated to BLM-treated mice, they tuned the differentiation of Gr-1HighCD11b+ toward Gr-1LowCD11b+ cells. Gr-1LowCD11b+ cells exhibited unsegmented nuclei and expressed F4/80, Ly-6C, CD49d, and CD115 markers. These cells had potent immunosuppressive activity and thus could be defined as monocytic MDSC. As a result of such immunoregulation, BMSC mediated a decrease of pro-inflammatory products and amelioration of lung injury in BLM-treated mice. Further study using antibody array showed increased expression of macrophage colony-stimulating factor (M-CSF) in BMSC-treated mice. Accumulation of Gr-1LowCD11b+ cells in BMSC-treated mice was abrogated in M-CSF neutralizing mice. The beneficial effect of BMSC was independent of the ability of the cells to engraft in lung and in vitro coculture study of BMSC with Gr-1+CD11b+ cells showed that the induction of Gr-1LowCD11b+ cells by BMSC was independent of cell-cell contact. CONCLUSIONS: These results document the generation of Gr-1HighCD11b+ cells in BLM-treated mice, and suggest that BMSC tune the differentiation of Gr-1HighCD11b+ toward Gr-1LowCD11b+ cells and therefore inhibit the progression of BLM-induced lung injury.

Most MCF7 and SK-OV3 cells were deprived of their stem nature by Hoechst 33342.

Using clonal and population analysis, we found that the MCF7 and SK-OV3 were composed mainly of cancer stem cells. Together with SP analysis, we found that both SP and NSP cells of MCF7 and SK-OV3 contained different proportions of cancer stem cells. In addition, we discovered that MCF7 SP cells were able to generate non-SP cells, and conversely non-SP cells generated SP cells; Moreover, we showed that Hoechst 33342 and FACS were harmful to the clonogenicity of MCF7 and SK-OV3 cells.

Surgery-induced monocytic myeloid-derived suppressor cells expand regulatory T cells in lung cancer.

While monocytic myeloid-derived suppressor cells (M-MDSCs) have been reported to induce the development of regulatory T cells (Treg), little is known about their correlation with Treg during perioperative period. Here, we demonstrated that the M-MDSCs expressing CD11b+CD33+HLA-DR-CD14+ in lung cancer patients after thoractomy significantly increased in comparison with preoperation, and their accumulation linearly correlated with an increase in Treg. Surgery-induced M-MDSCs, in addition to have high arginase activity, were more efficient in suppressing T-cell proliferation. Furthermore, the surgery-induced Treg expressed high levels of Foxp3, PD-1 and CTLA-4. Surgery-induced M-MDSCs were more potent in expending Treg when cocultured with autologous T cells in vitro. Using a lung metastasis mouse model, we demonstrated that the M-MDSCs at postoperative period were significantly increased and linearly correlated with Treg. We also showed that all-trans retinoic acid significantly inhibited the induction and proliferation of M-MDSCs, suppressed expansion of Treg, and finally prevented tumor metastasis in the mice after tumor resection. Receiver operating characteristic analyses revealed the superiority of surgery-induced M-MDSCs and Treg to those at preoperative period as a prognostic marker for lung cancer patients. Taken together, our results link the presence of surgery-induced M-MDSCs with the emergence of Treg and identify M-MDSCs and Treg derived postoperatively as potential indicators of tumor metastasis.

NEAT1 is Required for Survival of Breast Cancer Cells Through FUS and miR-548.

Increasing evidence shows that long noncoding RNAs (lncRNAs) have important roles in the regulation of multiple cellular processes, including cell division, cell growth, and apoptosis, as well as cancer metastasis and neurological disease progression; however, the mechanism of how lncRNAs regulate these processes is not well established. In this study, we demonstrated that downregulating the expression of the lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1) in breast cancer cells inhibited cell growth and induced cell apoptosis. In addition, the RNA-binding protein fused in sarcoma/translocated in liposarcoma (FUS/TLS) physically interacted with NEAT1, and reducing the expression of FUS/TLS also induced cell apoptosis. Multiple miRNAs were identified as regulators of NEAT1, but only overexpression of miR-548ar was able to decrease NEAT1 expression and promote apoptosis. These results indicate a novel interaction between NEAT1, miR-548ar-3p, and FUS and their role in the regulation of breast cancer cell apoptosis.

Bone marrow mesenchymal stem cells suppress ascitogenous hepatoma progression in BALB/c mouse through reducing myeloid-derived suppressor cells.

Bone marrow mesenchymal stem cells (BMSCs) and myeloid-derived suppressor cells (MDSCs) can be mobilized from bone marrow (BM) into blood stream and home in tumor stroma, where they either help or hinder tumor growth. The issue of whether BMSCs could affect MDSCs in ascitogenous hepatoma BALB/c mice, thus influencing their functional activity, remains unclear. In this study, we demonstrated that after transfusion into ascitogenous hepatoma BALB/c mice, the homing fraction of BMSCs in BM was 2%-5% in 24-72 h and the percentage of Gr-1+CD11b+ MDSCs was downregulated in peripheral blood (PB) and BM. Meanwhile, IFN-γ+ T lymphocytes in PB increased. As a result of such immunoregulation, BMSCs treatment caused a delayed tumor growth and a prolonged survival in H22 ascitogenous hepatoma model. Because the proliferation of H22 cells was not affected by in vitro coculture with BMSCs, this observation is likely due to a systemic suppressive effect on the host MDSCs. We also demonstrated that BMSCs inhibited the induction and proliferation of MDSCs from hematopoietic stem cells (HSCs) in an in vitro tumor conditioned medium. Thus, our findings show for the first time that BMSCs are potentially inhibitor during MDSCs induction and proliferation and that when injected intravenously into tumor bearing mice they might be effective antitumor agents suitable for cancer therapy.