Objective: To observe the platinum drugs resistance effect of N-acetyltransferase 10 (NAT10) overexpression in breast cancer cell line and elucidate the underlining mechanisms. Methods: The experiment was divided into wild-type (MCF-7 wild-type cells without any treatment) group, NAT10 overexpression group (H-NAT10 plasmid transfected into MCF-7 cells) and NAT10 knockdown group (SH-NAT10 plasmid transfected into MCF-7 cells). The invasion was detected by Transwell array, the interaction between NAT10 and PARP1 was detected by co-immunoprecipitation. The impact of NAT10 overexpression or knockdown on the acetylation level of PARP1 and its half-life was also determined. Immunostaining and IP array were used to detect the recruitment of DNA damage repair protein by acetylated PARP1. Flow cytometry was used to detect the cell apoptosis. Results: Transwell invasion assay showed that the number of cell invasion was 483.00±46.90 in the NAT10 overexpression group, 469.00±40.50 in the NAT10 knockdown group, and 445.00±35.50 in the MCF-7 wild-type cells, and the differences were not statistically significant (P>0.05). In the presence of 10 μmol/L oxaliplatin, the number of cell invasion was 502.00±45.60 in the NAT10 overexpression group and 105.00±20.50 in the NAT10 knockdown group, both statistically significant (P<0.05) compared with 219.00±31.50 in wild-type cells. In the presence of 10 μmol/L oxaliplatin, NAT10 overexpression enhanced the binding of PARP1 to NAT10 compared with wild-type cells, whereas the use of the NAT10 inhibitor Remodelin inhibited the mutual binding of the two. Overexpression of NAT10 induced PARP1 acetylation followed by increased PARP1 binding to XRCC1, and knockdown of NAT10 expression reduced PARP1 binding to XRCC1. Overexpression of NAT10 enhanced PARP1 binding to LIG3, while knockdown of NAT10 expression decreased PARP1 binding to LIG3. In 10 μmol/L oxaliplatin-treated cells, the γH2AX expression level was 0.38±0.02 in NAT10 overexpressing cells and 1.36±0.15 in NAT10 knockdown cells, both statistically significant (P<0.05) compared with 1.00±0.00 in wild-type cells. In 10 μmol/L oxaliplatin treated cells, the apoptosis rate was (6.54±0.68)% in the NAT10 overexpression group and (12.98±2.54)% in the NAT10 knockdown group, both of which were statistically significant (P<0.05) compared with (9.67±0.37)% in wild-type cells. Conclusion: NAT10 overexpression enhances the binding of NAT10 to PARP1 and promotes the acetylation of PARP1, which in turn prolongs the half-life of PARP1, thus enhancing PARP1 recruitment of DNA damage repair related proteins to the damage sites, promoting DNA damage repair and ultimately the survival of breast cancer cells.
Breast Neoplasms/enzymology* ; Cell Line, Tumor ; Drug Resistance, Neoplasm ; Female ; Humans ; MCF-7 Cells ; N-Terminal Acetyltransferases/metabolism* ; Organoplatinum Compounds/pharmacology* ; Oxaliplatin/pharmacology* ; X-ray Repair Cross Complementing Protein 1

Cullin-RING E3 ligases (CRLs) are the major components of ubiquitin-proteasome system, responsible for ubiquitylation and subsequent degradation of thousands of cellular proteins. CRLs play vital roles in the regulation of multiple cellular processes, including cell cycle, cell apoptosis, DNA replication, signalling transduction among the others, and are frequently dysregulated in many human cancers. The discovery of specific neddylation inhibitors, represented by MLN4924, has validated CRLs as promising targets for anti-cancer therapies with a growing market. Recent studies have focused on the discovery of the CRLs inhibitors by a variety of approaches, including high through-put screen, virtual screen or structure-based drug design. The field is, however, still facing the major challenging, since CRLs are a large multi-unit protein family without typical active pockets to facilitate the drug design, and enzymatic activity is mainly dependent on undruggable protein-protein interactions and dynamic conformation changes. Up to now, most reported CRLs inhibitors are aiming at targeting the F-box family proteins (e.g., SKP2, β-TrCP and FBXW7), the substrate recognition subunit of SCF E3 ligases. Other studies reported few small molecule inhibitors targeting the UBE2M-DCN1 interaction, which specifically inhibits CRL3/CRL1 by blocking the cullin neddylation. On the other hand, several CRL activators have been reported, such as plant auxin and immunomodulatory imide drugs, thalidomide. Finally, proteolysis-targeting chimeras (PROTACs) has emerged as a new technology in the field of drug discovery, specifically targeting the undruggable protein-protein interaction. The technique connects the small molecule that selectively binds to a target protein to a CRL E3 via a chemical linker to trigger the degradation of target protein. The PROTAC has become a hotspot in the field of E3-ligase-based anti-cancer drug discovery.
Antineoplastic Agents ; pharmacology ; therapeutic use ; Drug Design ; Drug Discovery ; Enzyme Inhibitors ; pharmacology ; therapeutic use ; Humans ; Neoplasms ; enzymology ; Ubiquitin-Protein Ligases ; metabolism ; Ubiquitination ; drug effects

The present study was aimed to investigate the effect of Janus kinase 3 (JAK3) on the migration of breast cancer cells and the underlying mechanism. The expression of JAK3 in breast cancer MCF-7 cells was silenced by siRNA (siJAK3). The migration ability of MCF-7 cells was detected by scratch test. The activity of store-operated calcium channel (SOCC) was detected by fluorescence calcium imaging. The expression levels of Orai1 and STIM1, key molecules in the process of store-operated calcium entry (SOCE) were detected by Western blot and RT-PCR. The results showed that 2-APB, an inhibitor of SOCC, could inhibit the migration ability of MCF-7 cells. siJAK3 transfection significantly inhibited the migration ability of MCF-7 cells, decreased the activity of SOCC, and down-regulated mRNA and protein expression levels of Orai1 and Stim1. Over-expression of Orai1 or STIM1 in JAK3-silenced cells restored their migration ability. These results suggest that JAK3 facilitates the migration of breast cancer cells by SOCC.
Breast Neoplasms ; enzymology ; Calcium ; metabolism ; Calcium Channels ; metabolism ; Cell Movement ; physiology ; Gene Expression Regulation, Neoplastic ; Humans ; Janus Kinase 3 ; genetics ; metabolism ; MCF-7 Cells ; ORAI1 Protein ; genetics

OBJECTIVE: To investigate the differentially expressed genes between gastric cancer and normal gastric mucosa by bioinformatics analysis, identify the important gene participating in the occurrence and progression of gastric cancer, and predict the functions of these genes. METHODS: The gene expression microarray data GSE100935 (including 18 gastric cancer samples and normal gastric mucosal tissues) downloaded from the GEO expression profile database were analyzed using Morpheus to obtain the differentially expressed genes in gastric cancer, and a cluster analysis heat map was constructed. The online database UALCAN was used to obtain the expression levels of these differentially expressed genes in gastric cancer and normal gastric mucosa. The prognostic value of the differentially expressed genes in gastric cancer was evaluated with Kaplan-Meier survival analysis. GO functional enrichment analysis was performed using Fun-Rich software, and the STRING database was exploited to establish a PPI network for the differentially expressed genes. RESULTS: A total of 45119 differentially expressed genes were identified from GSE100935 microarray data. Analysis with UALCAN showed an obvious high expression of EXD3 gene in gastric cancer, and survival analysis suggested that a high expression level of EXD3 was associated with a poorer prognosis of the patients with gastric cancer. GO functional enrichment analysis found that the differentially expressed genes in gastric cancer were involved mainly in the regulation of nucleotide metabolism and the activity of transcription factors in the cancer cells. CONCLUSIONS EXD3 may be a potential oncogene in gastric cancer possibly in relation to DNA damage repair. The up-regulation of EXD3 plays an important role in the development and prognosis of gastric cancer, and may serve as an important indicator for prognostic evaluation of the patients.
Computational Biology ; Databases, Genetic ; Exonucleases ; genetics ; Gastric Mucosa ; chemistry ; enzymology ; Gene Expression Profiling ; Gene Expression Regulation, Neoplastic ; Humans ; Neoplasm Proteins ; genetics ; Prognosis ; Stomach Neoplasms ; enzymology ; genetics ; mortality

ErbB receptor tyrosine kinase inhibitors (EGFR-TKI), gefitinib, erlotinib, icotinib and aftinib, which are approved as a frontline treatment for patients with non-small cell lung cancer (NSCLC) who have tumors harboring EGFR mutations in China. And osimertinib was approved in second line setting for patients with EGFRT 790M-positive NSCLC. Rash, paronychia, diarrhea, stomatitis, liver dysfunction and (interstitial lung disease, ILD) are frequently observed in patients treated with EGFR-TKI. Chinese Society of Lung Cancer, Chinese Anti-Cancer Association, organized Chinese experts to develop the Chinese expert consensus on EGFR-TKI adverse event (AE) management based on domestic diagnosis and treatment of ADR and also incorporating international updated theory and recommendations.
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Antineoplastic Agents ; adverse effects ; therapeutic use ; Carcinoma, Non-Small-Cell Lung ; drug therapy ; enzymology ; genetics ; China ; Diarrhea ; etiology ; ErbB Receptors ; antagonists & inhibitors ; genetics ; metabolism ; Humans ; Liver Diseases ; etiology ; Lung Diseases ; etiology ; Lung Neoplasms ; drug therapy ; enzymology ; genetics ; Protein Kinase Inhibitors ; adverse effects ; therapeutic use ; Stomatitis ; etiology

With the development of sequencing technology, the detection rate of de novo T790M mutation is increasing. The emergence of the third generation of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) provide treatment opportunities. Secondary T790M mutation is often emphasized in clinic, but de novo T790M mutation is neglected. This review found that the incidence of de novo T790M mutation fluctuated greatly, which was mainly affected by sequencing techniques. The de novo T790M mutation is mainly low in mutation abundance, easy to combine with other gene changes, a poor predictor and prognostic factor and the efficacy of the first and second generation EGFR-TKIs is limited. The therapeutic value of osimertinib needs to be studied.
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Carcinoma, Non-Small-Cell Lung ; diagnosis ; drug therapy ; enzymology ; genetics ; ErbB Receptors ; antagonists & inhibitors ; genetics ; Humans ; Lung Neoplasms ; diagnosis ; drug therapy ; enzymology ; genetics ; Mutation ; Prognosis ; Protein Kinase Inhibitors ; pharmacology ; therapeutic use

BACKGROUND: Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) have demonstrated some dramatic efficacy in advanced non-small-cell lung cancer (NSCLC) patients with activating EGFR mutation. However, progression-free survivals (PFS) among those patients who were treated with first line EGFR TKIs were inconsistent. The aim of this study is to explore the association of clinical prognostic factors with EGFR-TKI efficacy in advanced NSCLC patients. METHODS: The demographic and clinical characteristics of 203 patients with activating EGFR mutation treated with first generation TKI as a first-line therapy were retrospectively reviewed. RESULTS: Of the 203 patients enrolled in this study, 139 patients had progression of disease and 63 patients died. The subjects had a median follow up duration of 21.1months and a median PFS of 14.3 months. Partial response (PR) was achieved in 127 (66.1%) patients and stable disease (SD) rate was achieved in 55 (28.6%) patients. In univariate analysis, patients with 2 or higher ECOG score (5.1 vs 16 months, P=0.033), SD as best overall response (9.5 vs 17.9 months, P=0.030), extrathoracic metastasis (11.7 vs 27.5 months, P=0.004), liver metastasis (4.1 vs 16.0 months, P=0.000), bone metastasis (13.3 vs 21.5months, P=0.027) and pulmonary embolism (5.5 vs 16.6 months, P=0.005) had shorter PFS than those without the listed factors. Multivariable Cox regression analysis showed best overall response (HR=1.825, 95%CI: 1.107-3.008, P=0.018) and liver metastasis (HR=1.694, 95%CI: 1.146-5.756, P=0.022) were independent predictive factors of shorter PFS. CONCLUSIONS Despite the high efficacy of EGFR-TKI, SD as best overall response and liver metastasis predicts poorer PFS in advanced NSCLC patients with EGFR gene mutations receiving first-line therapy treatment.
Adult ; Aged ; Antineoplastic Agents ; administration & dosage ; Carcinoma, Non-Small-Cell Lung ; drug therapy ; enzymology ; genetics ; mortality ; ErbB Receptors ; genetics ; metabolism ; Female ; Humans ; Lung Neoplasms ; drug therapy ; enzymology ; genetics ; Middle Aged ; Mutation ; Protein Kinase Inhibitors ; administration & dosage ; Retrospective Studies ; Treatment Outcome ; Young Adult

OBJECTIVEEscape from the body's immune response is a basic characteristic of lung cancer, and indoleamine-2,3-dioxygenase (IDO) plays a key role in mediating immune escape of non-small-cell lung cancer, which leads to recurrence and metastasis. Feiji Recipe, a compound Chinese herbal medicine, has the effect of stabilizing lesions and prolonging survival in patients with lung cancer. The purpose of this study was to investigate the mechanisms underlying the anticancer properties of Feiji Recipe.

METHODSAn orthotopic transplant model of mouse Lewis lung cancer, with stable expression of IDO gene, was established in C57BL/6 mice. Optical imaging was used to observe the effects of Feiji Recipe in the treatment of lung cancer in vivo. The effects of Feiji Recipe on the proliferation of mouse Lewis lung cancer cell line 2LL, 2LL-enhanced green fluorescent protein (2LL-EGFP) and 2LL-EGFP-IDO were investigated, and the apoptosis of T-cells was examined by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide using flow cytometry. Chemical composition of Feiji Recipe was validated by high-performance liquid chromatography.

RESULTSCompared to the control group, the survival of animals treated with Feiji Recipe was significantly prolonged (P = 0.0074), and the IDO protein level decreased (P = 0.0072); moreover, the percentages of CD4CD25 T-cells and Foxp3 T-cells were significantly decreased (P < 0.05). The molecular mechanism of Feiji Recipe against lung cancer may relate to the regulation of immune cells, such as T-cells and regulatory T-cells.

CONCLUSIONThe molecular mechanism of Feiji Recipe in treatment of lung cancer is to restore the function of T-cells in the cancer microenvironment through interfering with the IDO pathway.

Animals ; Apoptosis ; drug effects ; Carcinoma, Lewis Lung ; drug therapy ; enzymology ; immunology ; physiopathology ; Cell Proliferation ; drug effects ; Disease Models, Animal ; Drugs, Chinese Herbal ; administration & dosage ; Growth Inhibitors ; administration & dosage ; Humans ; Indoleamine-Pyrrole 2,3,-Dioxygenase ; genetics ; immunology ; Lung Neoplasms ; drug therapy ; enzymology ; immunology ; physiopathology ; Male ; Mice ; Mice, Inbred C57BL ; T-Lymphocytes, Regulatory ; drug effects ; immunology

PURPOSE: Previous retrospective studies suggest that anaplastic lymphoma kinase (ALK) mutation-positive (ALK+) non-small cell lung cancer (NSCLC) patients are sensitive to pemetrexed. To determine its efficacy, we retrospectively evaluated clinical outcomes of pemetrexed-based chemotherapy in patients with ALK+ NSCLC. MATERIALS AND METHODS: We identified 126 patients with advanced, ALK+ NSCLC who received first-line cytotoxic chemotherapy. We compared response, progression-free survival (PFS), and overall survival (OS) rates according to chemotherapy regimens. Furthermore, we evaluated intracranial time to tumor progression (TTP) and proportion of ALK+ cells as prognostic factors. RESULTS: Forty-eight patients received pemetrexed-based chemotherapy, while 78 received other regimens as first-line treatment. The pemetrexed-based chemotherapy group showed superior overall response (44.7% vs. 14.3%, p < 0.001) and disease control (85.1% vs. 62.3%, p=0.008) rates. The pemetrexed-based chemotherapy group also exhibited longer PFS (6.6 months vs. 3.8 months, p < 0.001); OS rates were not significantly different. The lack of exposure to second-generation ALK inhibitors and intracranial metastasis on initial diagnosis were independent negative prognostic factors of OS. Intracranial TTP was similar between the treatment groups (32.7 months vs. 35.7 months, p=0.733). Patients who harbored a greater number of ALK+ tumor cells (≥70%) showed prolonged OS on univariate analysis (not reached vs. 44.8 months, p=0.041), but not on multivariate analysis (hazard ratio: 0.19, 95% confidence interval: 0.03–1.42; p=0.106). CONCLUSION: Pemetrexed-based regimens may prolong PFS in patients with ALK+ NSCLC as a first-line treatment, but are not associated with prolonged OS. Exposure to second-generation ALK inhibitors may improve OS rates in patients with ALK+ NSCLC.
Adult ; Aged ; Antineoplastic Agents/*therapeutic use ; Carcinoma, Non-Small-Cell Lung/*drug therapy/enzymology/mortality ; Disease-Free Survival ; Female ; Humans ; Lung Neoplasms/*drug therapy/enzymology/mortality ; Male ; Middle Aged ; Mutation ; Pemetrexed/*therapeutic use ; Receptor Protein-Tyrosine Kinases/genetics ; Retrospective Studies ; Survival Rate ; Treatment Outcome

Metastasis is responsible for the majority of cancer-related deaths and prevention of metastasis remains a big challenge for cancer therapy. Cucurbitacin B (Cuc B) is a natural triterpenoid with potent anticancer activities while its effect on metastasis remains unclear. In the present study, the inhibitory effect and mechanisms of Cuc B on metastasis were investigated in MDA-MB-231 breast cancer cells. The cells were treated with or without Cuc B, and the cytotoxicity was determined by MTT assay. The effect of Cuc B on metastasis was evaluated with wound healing, transwell, and adhesion assays. Furthermore, the adhesion of cancer cells to endothelial cells was determined. The protein expression was determined by Western blotting. Cuc B (< 100 nmol·L) showed no obvious cytotoxicity to MDA-MB-231 cells, but significantly inhibited migration, invasion, and adhesion to Matrigel, fibronectin, type I collagen, and endothelial cells. Cuc B dramatically inhibited the phosphorylation of focal adhesion kinase (FAK) and paxillin in dose- and time-dependent manners. Furthermore, Cuc B induced intracellular reactive oxygen species (ROS) generation, which could be reduced by N-acetyl-l-cysteine (NAC). In addition, NAC pretreatment could reverse Cuc B-induced suppression of migration and adhesion, expression of FAK, but showed no effect on paxillin expression. In summary, Cuc B suppressed ROS-dependent metastasis through FAK pathway in breast cancer MDA-MB-231 cells, demonstrating novel mechanisms for the anticancer effects of Cuc B.
Acetylcysteine ; pharmacology ; Antineoplastic Agents ; pharmacology ; Breast Neoplasms ; enzymology ; metabolism ; pathology ; physiopathology ; Cell Adhesion ; drug effects ; Cell Line, Tumor ; Cell Movement ; drug effects ; Collagen Type I ; metabolism ; Dose-Response Relationship, Drug ; Down-Regulation ; drug effects ; Female ; Fibronectins ; metabolism ; Focal Adhesion Kinase 1 ; metabolism ; Humans ; Neoplasm Invasiveness ; pathology ; Neoplasm Metastasis ; pathology ; Paxillin ; metabolism ; Phosphorylation ; drug effects ; Reactive Oxygen Species ; metabolism ; Triterpenes ; antagonists & inhibitors ; chemistry ; pharmacology