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Background Triple-negative breast cancer (TNBC) patients have relatively poor clinical outcomes. A marker predicting the prognosis of patients with TNBC could help guide treatment. Extensive evidence demonstrates that angiopoietin-like 4 (ANGPTL4) is involved in the regulation of cancer growth, metastasis and angiogenesis. Therefore, its role in TNBC is of interest. Methods: We tested the ANGPTL4 expression level in tumor tissues by immunohistochemistry (IHC) and detected its association with the clinical features of TNBC patients. Next, the effects and mechanisms of ANGPTL4 on TNBC cell migration and adhesion were investigated. Results We found that ANGPTL4 overexpression was associated with favorable outcomes in TNBC patients. ANGPTL4 upregulation inhibited cell adhesion, migration and invasion in vitro. Further analyses demonstrated that the possible mechanism might involve suppression of TNBC progression by interacting with extracellular matrix-related genes. Conclusions The present findings demonstrated that enhancement of ANGPTL4 expression might inversely correlate with TNBC progression. ANGPTL4 is a promising marker of TNBC and should be evaluated in further studies. Trial registration Retrospectively registered.

Background: Bcl-2 family members play an important role in the development of malignant lymphoma and can induce drug resistance in anticancer treatment. The development of small molecules targeting Bcl-2 family protein can be new strategy for malignant lymphoma treatment. In this study, we investigate the antitumor effect and the cellular mechanism of a novel Bcl-2/Bcl-xL dual inhibitor BM-1197 in DCBCL and Burkitt lymphoma cells. Methods: CCK-8 assay was used to detect cell viability. Apoptosis was determined by Hoechst 33258 staining and flow cytometry. The activity of caspase-3/caspase-9 was determined using the caspase-3/ caspase-9 activity kit. Western blotting analysis was performed to evaluate the change of protein expression. The functional analysis was evalueated via immunoprecipitation and siRNA interference. Human malignant lymphoma xenograft models in nude mice were established for in vivo efficacy detection. Results: We find that BM-1197 exerts potent growth-inhibitory activity against lymphoma cells which harbor Bcl-2 and Bcl-xL high expression in vitro and has synergistic effect with chemotherapeutic drugs. Mechanistically, we see that the intrinsic apoptosis pathway is activated upon BM-1197 treatment. BM-1197 affects the protein interaction of Bak/Bcl-xl, Bim/Bcl-2, Bim/Bcl-xl, PUMA/Bcl-2 and induced conformational change in the Bax protein.which results in activation of Bax and release cytochrome c, and activated caspase -9, -3, -7 and finally induce cell apoptosis. Furthermore, our data demonstrates that BM-1197 exhibits strong anti-tumor effects against established human malignant lymphoma xenograft models. Conclusions: Our study demonstrated BM-1197 exerts potent antitumor effects both in vitro and in vivo, and provides promising preclinical data for further development of BM-1197 in malignant lymphoma. Funding Statement: This work is supported by National Natural Scientific Research Fund of China (Project Number: 81301904), Medical Scientific Technology and Research Fund of Guangdong (Project Number: A2016023), Special Project by Guangdong Science and Technology Department (2018YJ021), and National Natural Scientific Research Fund of China (Project Number: 81101671) Declaration of Interests: The authors declare that they have no competing interests. Ethics Approval Statement: All animal experiments were performed under the guidance of Sun Yat-Sen University Committee for Use and Care of Laboratory Animals and approved by the animal experimentation ethics committee.

Purpose Immune suppression is common in patients with advanced breast cancer but the mechanisms underlying this phenomenon have not been sufficiently studied. In this study, we aimed to identify B7 family members that were able to predict the immune status of patients, and which may serve as potential targets for the treatment of breast cancer. We also aimed to identify microRNAs that may regulate the expression of B7 family members. Methods The Cancer Genome Atlas data from 1,092 patients with breast cancer, including gene expression, microRNA expression and survival data, were used for statistical and survival analyses. Polymerase chain reaction and Western blot were used to measure messenger RNA and protein expression, respectively. Luciferase assay was used to investigate direct microRNA target. Results Bioinformatic analysis predicted that microRNA (miR)-93, miR-195, miR-497, and miR-340 are potential regulators of the immune evasion of breast cancer cells, and that they exert this function by targeting CD274, PDCD1LG2, and NCR3LG1. We chose CD274 for further investigations. We found that miR-195, miR-497, and CD274 expression levels were inversely correlated in MDA-MB-231 cells, and miR-195 and miR-497 expressions mimic inhibited CD274 expression in vitro. Mechanistic investigations demonstrated that miR-195 and miR-497 directly target CD274 3' untranslated region. Conclusion Our data indicated that the level of B7 family members can predict the prognosis of breast cancer patients, and miR-195/miR-497 regulate CD274 expression in triple negative breast cancer. This regulation may further influence tumor progression and the immune tolerance mechanism in breast cancer and may be able to predict the effect of immunotherapy on patients.

Hypoxia-inducible factor-1 (HIF-1) is a primary transcriptional factor that targets a series of genes participating in angiogenesis and cell proliferation. HIF-1 is a heterodimer consisting of a constitutively-expressed HIF-1β subunit and an oxygen-regulated HIF-1α subunit. Overexpression of HIF-1α has been found in various types of cancer. Targeting HIF-1α may be a novel approach to cancer therapy. Previous findings showed that a newly synthesized compound (Z)-3,4',5-trimethoxylstilbene-3'-O-phosphate disodium (M410), an analogue of the microtubule-targeting agent, combretastatin A4, inhibited the polymerization of bovine brain tubulin and induced mitotic arrest. The aim of the present study was to determine the mechanism of M410 destabilizes microtubules and inhibits HIF-1α in breast cancer cells. We performed 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, immunofluorescence and confocal microscopy, ELISA assay, transient transfections and reporter gene assay, immunoblot analysis and isolation and analysis of RNA to evaluate the mechanisms of M410 on breast cancer. SPSS 17.0 was used to analyze the data. The results showed that the growth of breast cancer cells was inhibited in a dose-dependent manner. MDA-MB-231 was the most sensitive, with a 50% growth inhibition (GI50) of 111.4±2.2 nM. HIF-1α expression was clearly reduced following M410 treatment in a dose-dependent manner. M410 downregulated the nuclear accumulation of HIF-1α, and the strong correlation between disruption of the microtubule cytoskeleton and the inhibition of HIF-1α expression was independent of mitotic arrest. Furthermore, M410 inhibited HIF-1α at the post-transcriptional level and inhibited the vascular endothelial growth factor (VEGF) at the transcription level. M410 downregulated HIF-1α expression in a proteasome-independent manner. In conclusion, M410 depolymerized microtubules and downregulated HIF-1α protein levels in a proteasome-independent manner and reduced the mRNA of HIF-1-targeted genes in the MDA-MB-231 breast cancer cell line.

Background Anti-programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) immunotherapy has been proved to be effective on gastric cancer in ongoing clinical trials. However, the value of PD-L1 in predicting responses of patients with gastric cancer to anti-PD-1/PD-L1 immunotherapy is controversial. Some studies suggested that intra- and inter-tumoral heterogeneity of PD-L1 expression might explain the controversy. This study aimed to analyze the expression of PD-L1, PD-L2, and PD-1 as well as CD8(+) T-cell density in primary tumors and lymph nodes from patients with stage T1-4N+M0 gastric adenocarcinoma to explore the heterogeneity of PD-1 signaling pathway molecules. Methods In primary tumors and metastatic as well as non-metastatic lymph nodes from patients with stage T1-4N+M0 gastric adenocarcinoma, we detected PD-L1 and PD-L2 expression with immunohistochemistry. CD8(+) T-cell density in primary tumors and PD-1 expression on CD8(+) T cells were detected with immunofluorescence. Univariate analysis was used to determine the prognostic values of them. Cox proportional hazard regression model was used to identify independent risk factors that affect patients’ overall survival and disease-free survival. Results Among 119 eligible patients who had undergone surgical resection, the positive rate of PD-L1 was higher in metastatic lymph nodes than in primary tumors (45.4% vs. 38.7%, P = 0.005); the positive rate of PD-1 on CD8(+) T cells was significantly higher in primary tumors and metastatic lymph nodes than in tumor-free lymph nodes (both P

Diarylquinoline compounds are newly synthesized derivatives of the new anti-tuberculosis drug, TMC207. In this study, nine diarylquinoline compounds were screened for cytotoxic activity against human tumor cells, and their mechanisms of action were investigated. Among the nine compounds, STM-57 [N-((6-bromo-2-methoxyquinolin-3-yl)(phenyl)methl)-N-(3,4-dichlorophenyl)-3-(4 -methylpiperazin-1-yl)propanamide] showed potent cytotoxic activity. STM-57 induced caspase-independent cell death in the human nasopharyngeal carcinoma cell line, CNE-2. Further investigation showed that STM-57 induced autophagy, as determined with the increased expression of green fluorescent protein-light chain 3 (GFP-LC3) and increased LC3-II levels. STM-57 inhibited the phosphorylation of Akt and the mammalian target of rapamycin (mTOR) in CNE-2 cells. The intracellular calcium concentration and reactive oxygen species levels were increased in CNE-2 cells following treatment with STM-57, whereas the mitochondrial transmembrane potential (ΔΨm) and ATP concentrations were decreased.

Vascular disrupting agents (VDAs) have emerged as a new kind of anti-cancer drug in recent years. Structural modification of an active parent compound is an effective approach to developing new agents with more activity and fewer adverse reactions. In our study, six synthesized stilbene derivatives were screened for their cytotoxic activity against human tumor cells, and their mechanisms of action were investigated. The MTT assay was used to determine the anti-proliferative activity of these compounds. Polymerization of tubulin was detected by a tubulin assembly assay, and the cellular microtubule network was observed by immunocytochemical analyses. Cell-cycle distribution was detected by flow cytometry. A nude mouse model with xenografted colon cancer was used to demonstrate the in vivo anti-tumor activity, and microvessel density (MVD) was determined by immunohistochemistry. The expression levels of protein and mRNA were detected by Western blot and RT-PCR, respectively. Among the six newly synthesized compounds, (Z)-3,4',5-trimethoxylstilbene-3'-O-phosphate disodium (M410) showed potent cytotoxic activity toward proliferating tumor cells and exhibited a similar cytotoxicity against multi-drug resistant (MDR) tumor cells. M410 inhibited bovine brain tubulin polymerization in a way similar to that of colchicine. In proliferating human umbilical vein endothelial cells (HUVECs), 20 nM of M410 induced cellular tubulin depolymerization within 4 h, which led to M phase arrest. Systemic administration of M410 at nontoxic doses in nude mice resulted in inhibition of tumor growth of human colon cancer LoVo xenografts. The tumor vessel density also decreased after M410 treatment, as determined by immunohistochemical staining for CD31. M410 downregulated hypoxia-inducible factor-1 alpha (HIF-1α) expression, reduced nuclear HIF-1α, and downregulated vascular endothelial cell growth factor (VEGF) mRNA. Our results indicate that M410 is a potent microtubule inhibitor that is cytotoxic, angiogenesis inhibiting and vascular targeting.

Cantharidin is a natural toxin that possesses potent anti-tumor properties. Its clinical application, however, is limited due to severe side-effects. Its cytotoxicity is believed to be mediated by the inhibition of serine/threonine protein phosphatase 2A. In order to identify new compounds with potential clinical therapeutic use, a series of cantharidin analogues, including those with skeletal modifications at 1-C position (analogues 1-6) and those with anhydride modifications (analogues 7-13), were synthesized, and tested for their inhibitory effects on protein phosphatase 2A and their cytotoxicity to a panel of cancer cell lines. In addition, the mode of inhibition of cantharidin and analogue 13 on protein phosphatase 2A was determined by enzymatic kinetics assay. The data indicated that analogue 13 exhibited potent cytotoxicity to all cancer cell lines, and analogues 9, 11 and 12 showed relatively weak cytotoxicity to one or more cell lines, while other analogues showed little cytotoxicity. Accordingly, analogue 13 exhibited potent inhibitory activity on protein phosphatase 2A, and analogues 9, 11 and 12 showed weak inhibitory activity, while other analogues did not show any inhibitory activity. The findings indicate that the cytotoxicity of synthetic cantharidin analogues is likely to be associated with their protein phosphatase 2A inhibitory activity. The mode of inhibition of cantharidin and analogue 13 on protein phosphatase 2A is identified as noncompetitive inhibition by the Lineweaver-Burk plot.

Previous studies have indicated that trichosanthin (TCS) exerts antitumor activity by inducing apoptosis in numerous tumor cell lines. However, the effects of TCS on lymphoma remain to be elucidated. The current study demonstrated that TCS inhibited the proliferation of thirteen lymphoma cell lines in a dose‑dependent manner, with SU‑DHL‑2 cells exhibiting the greatest sensitivity to TCS. Treatment of SU‑DHL‑2 cells with TCS led to cell cycle arrest at the S to G2/M phase transition. Furthermore, flow cytometric analysis, Hoechst 33258 staining and western blotting indicated that TCS induced the apoptosis of SU‑DHL‑2 cells in a time‑ and concentration‑dependent manner. In addition, the activation of caspase‑3 and ‑7 and poly (ADP‑ribose) polymerase were observed. Pharmacological pan-caspase inhibition was observed to reduce TCS‑induced apoptosis. Inhibition of caspase‑8 or ‑9 alone was observed to partially reverse the effect of TCS on apoptosis. In conclusion, the current study indicates that TCS may induce apoptosis in SU‑DHL‑2 cells via the extrinsic and intrinsic pathways.

Breast cancer is one of the most common malignancies in women. Approximately 15% of the patients belong to the triple-negative breast cancer (TNBC) group, and have the disadvantage of not benefiting from currently available receptor-targeted systemic therapies. Some cancers in the TNBC group harbor defects in DNA double-strand break repair by homologous recombination (HR), such as BRCA1 dysfunction, and are hypersensitive to poly (ADP-ribose) polymerase (PARP) inhibition. However, only a small fraction of the tumors are BRCA-deficient, and this restricts the therapeutic utility of the PARP inhibitor monotherapy. Cyclin-dependent kinase 1 (CDK1) is necessary not only for BRCA1-mediated S phase checkpoint activation, but also for HR, because it phosphorylates BRCA1 for the efficient formation of BRCA1 foci. In this study, we showed that the combined inhibition of CDK1 and PARP in BRCA-proficient MDA-MB-231 breast cancer cells resulted in dramatically reduced cell growth compared to PARP inhibition alone. Mechanistic investigations revealed that this sensitivity appears to be mediated by sustained DNA damage and inefficient DNA repair triggering mitochondrial-mediated apoptosis as well as autophagy. Our results suggest that CDK1 inhibition represents a plausible strategy for expanding the utility of PARP inhibitors to BRCA‑proficient breast cancers.

Circadian rhythm has been linked to cancer genesis and development, but the detailed mechanism by which circadian disruption accelerates tumor growth remains unclear. The purpose of this study was to investigate the effect of circadian disruption on tumor growth and metastasis in male C57BL/6 mice, using an experimental chronic jet lag model. Lewis lung carcinoma cells were inoculated into both flanks of the mice following 10 days of exposure to experimental chronic jet lag or control conditions. The effects on tumor growth and lung metastasis were assessed, and the effect on gene expression was detected using cDNA microarrays and real-time quantitative RT-PCR. Tumors grew faster in the experimental chronic jet lag mice compared to the control mice (P=0.004). Lung metastases were found in 10 out of 24 mice in the chronic jet lag group, but only in 3 out of 24 mice in the LD group (P=0.023). Microarray data showed that in both liver and tumors circadian disruption altered the expression of genes, including those related to the cell cycle, apoptosis, the immune response and metastasis suppressor genes. The expression of the Ndrg1 gene was suppressed by chronic jet lag. We conclude that circadian disruption can promote tumor progression and metastasis by affecting the expression of both tumor-related genes and metastasis suppressor genes.

No randomized trial has been reported comparing different chemotherapy regimens on disseminated nasopharyngeal carcinoma (NPC). This study aims to compare five cisplatin-based regimens including cisplatin + 5-fluororacil (PF), paclitaxel + cisplatin (TP), gemcitabine + cisplain (GP), paclitaxel + cisplatin + 5-fluororacil (TPF), and bleomycin + cisplatin + 5-fluororacil (BPF) regimen most frequently used as the first-line protocols for metastatic NPC retrospectively. Eight hundred and twenty-two patients with metastatic NPC were divided into five groups according to the regimen they received. Then, their response rate, toxicity, and long-term survival outcome as well as the prognostic factors were analyzed. The higher response rates in GP and TPF regimens comparing to PF regimen were achieved (Χ 2 = 4.57, P = 0.033; Χ 2 = 7.04, P = 0.008), as well as in TPF regimen comparing to TP regimen (Χ 2 = 5.579, P = 0.018). The occurrence rate of the major III–IV grade toxicity was significantly different between the five groups. However, no statistically significant difference was observed in progression-free survival (PFS; P = 0.247) and overall survival (P = 0.127) among the five groups. Cox multivariate analysis identified the following independent prognostic factors: liver metastases, plasma Epstein Barr Virus (EBV)-DNA level, cycles of chemotherapy, and second-line chemotherapy. PF, TP, and GP are all effective regimens as the first-line chemotherapy for metastatic NPC, which can be well tolerated. Over four cycles of chemotherapy are recommended under no contraindication. Patients should transfer to the second-line regimen after the treatment failure of the first-line chemotherapy.

MicroRNA deregulation plays a major role in the initiation and progression of many cancers. The objective of this study is to evaluate the role of miR-181a in the metastasis of salivary adenoid cystic carcinoma (SACC). We identified a panel of differentially expressed microRNAs in two pairs SACC cell lines with different metastatic potential using microarrays. Among these differentially expressed microRNAs, the down-regulation of miR-181a was further validated by quantitative RT-PCR. Functional analysis indicated that miR-181a inhibits SACC cell migration, invasion and proliferation in vitro and in vivo. Ectopic transfection of miR-181a inhibited the expression of NGF, VEGF, TGFβ2, ERK1/2, pERK1/2 and Slug in SACC-LM cells which had higher expression of these genes compared to SACC-83 cells; while inverse results were found in miR-181a LNA transfected SACC-83 cells. The direct targeting of miR-181a to the Slug and ERK2 mRNAs were confirmed by luciferase reporter gene assays. SiRNA-mediated knockdown of Slug, ERK2 led to reduced cell migration and invasion of SACC, and knockdown of ERK2 suppresses the expression of Slug. Taken together, these results suggest that microRNA deregulation (i.e., down-regulation of miR-181a) contributes to the metastasis of SACC. MiR-181a-mediated suppression of SACC metastasis may be achieved in part by directly targeting Slug and ERK2 and regulating ERK/Slug pathway. Citation Format: Qianting He, Xiaofeng Zhou, Su Li, Zhujian Chen, Dan Chen, Yuchen Cai, Zhonghua Liu, Tingting Zhao, Anxun Wang. MicroRNA-181a suppresses salivary adenoid cystic carcinoma metastasis by targeting the ERK/Slug pathway. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5328. doi:10.1158/1538-7445.AM2013-5328

In previous studies, we demonstrated that dysregulation of manganese superoxide dismutase (SOD2) is a frequent event in tongue squamous cell carcinoma (TSCC) and is associated with lymph node metastasis. Here, we further investigated the mechanism of SOD2-mediated cell migration and invasion in paired TSCC cell lines with different metastatic potential. The UM1 and UM2 are paired cell lines from a single TSCC patient, where UM1 is more aggressive than UM2 in term of cell migration and invasion. Compared to UM2 cells, UM1 cells exhibited significantly higher SOD2 activity, increased intracellular H2O2 and higher levels of Snail, MMP-1 and pERK1/2 protein, and lower level of E-cadtherin protein. Upon knockdown of SOD2 by RNA interference, UM1 cells displayed significantly reduced cell migration and invasion abilities. This is accompanied by reductions in SOD2 activities, intracellular H2O2, levels of Snail, MMP-1 and pERK1/2 proteins, as well as increase in the level of E-cadtherin protein. Cell migration and invasion of the UM2 and the SOD2 shRNA-treated UM1 cells were enhanced by H2O2 treatment. This H2O2-mediated cell migration and invasion is accompanied by increased levels of Snail, MMP-1 and pERK1/2 protein, and decreased level of E-cadtherin protein. Thus, we conclude that the SOD2-dependent production of H2O2 contributes to both cell migration and invasion of TSCC via the Snail signaling pathway through increased Snail, MMP-1 and pERK1/2 expression, and the repression of the E-cadtherin. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5322. doi:1538-7445.AM2012-5322

Norcantharidin (NCTD), a demethylated form of cantharidin, is currently used as an anti-cancer drug in China. However, the exact anti-cancer mechanism of NCTD on human cancer cells remains poorly understood. In the present study, NCTD inhibited proliferation and DNA replication effectively in HL-60 cells. DNA replication-initiation protein Cdc6 was cleaved after 12 h treatment with NCTD. This cleavage generated a truncated Cdc6 fragment with a relative molecular weight of 49 kDa and elongated treatment with NCTD resulted in a complete loss of Cdc6. In addition, we found that Cdc6 was present in both non-chromatin- and chromatin-bound fractions in the untreated HL-60 cells, and NCTD treatment led to the cleavage of Cdc6 in both fractions. NCTD-induced cleavage of Cdc6 was prevented by pre-treatment with caspase-3 inhibitor, suggesting the involvement of caspase-3 activity in the process. Furthermore, NCTD treatment resulted in apoptotic changes including granular nuclear morphology, DNA laddering and sub-G1 arrest in HL-60 cells. In conclusion, our study reveals that NCTD can inhibit DNA replication, and induce apoptosis and caspase-3-dependent cleavage of Cdc6. The anti-cancer effect of NCTD may be closely associated with the dysfunction of Cdc6 and our report is the first to put forward this point of view.