Cell Line SGC-7901 Research Articles

Synthesis and biological evaluation of marine alkaloid-oriented β-carboline analogues

Pityriacitrin is a marine alkaloid with typical β-carboline scaffold, and which has been proven to exhibit diverse biological functions. During the course of our research for highly active compounds from natural products, the pityriacitrin have also been isolated and identified from a Chinese Burkholderia sp. NBF227. So, in order to explore the potential functional molecules, a series of β-carboline analogues derived from pityriacitrin were designed and synthesized, and their in vitro cytotoxic activities against SGC-7901, A875, HepG2, and MARC145 cell lines were evaluated. The results demonstrated that some of these β-carboline derivatives exhibited moderate to good cytotoxic activities, especially, compound 9o with a special sulfonyl group presented the highest inhibitory activities against all tested cell lines with the IC50 values of 6.82 ± 0.98, 8.43 ± 1.93, 7.69 ± 2.17, 7.19 ± 1.43 μM, respectively, which might be used as lead compound for discovery of novel cytotoxic agents.

MicroRNA 495 Inhibits Proliferation and Metastasis and Promotes Apoptosis by Targeting Twist1 in Gastric Cancer Cells.

Recently, microRNAs (miRNAs) have been reported to participate in multiple biological processes. However, the effects of miR-495 on gastric cancer (GC) remain unclear. The purpose of this study was to explore the functions of miR-495 in GC cell proliferation, metastasis, and apoptosis. SGC-7901 and BGC-823 cell lines were transfected with miR-495 mimic, miR-495 inhibitor, and negative controls (mimic control and inhibitor control). The expressions of miR-495, cell viability, migration, apoptosis, and apoptosis-related factors were examined by qRT-PCR, trypan blue staining, Transwell, flow cytometry, and Western blot, respectively. Simultaneously, key factor expression levels of EMT were detected by qRT-PCR and Western blot. The direct target of miR-495 was confirmed by dual-luciferase assay. Additionally, sh-Twist1, pc-Twist1, and corresponding controls were transfected into SGC-7901 and BGC-823 cells, and the protein levels of EMT-associated factors were detected by Western blot. miR-495 was downregulated in GC cells. miR-495 expression level was effectively overexpressed or suppressed in SGC-7901 and BGC-823 cells. Overexpression of miR-495 significantly decreased cell viability and migration, increased apoptosis, and inhibited the EMT process. Suppression of miR-495 showed contrary results. Twist1 was clarified as a target gene of miR-495, and Twist1 silencing obviously reduced the promoting effect of miR-495 suppression on these biological processes. Twist1 silencing significantly blocked the EMT process in both SGC-7901 and BGC-823 cells. miR-495 inhibited proliferation and metastasis and promoted apoptosis by targeting Twist1 in GC cells. These data indicated that miR-495 might be a novel antitumor factor of GC and provide a new method for the treatment of GC.

Synthesis and bioevaluation of diarylpyrazoles as antiproliferative agents

Two series of diarylpyrazoles were designed as potential microtubule targeting agents. Twenty-eight target compounds were synthesized and exhibited potent antiproliferative activity. Compound 15e, displayed potent antiproliferative activity against SGC-7901, KB and HT-1080 cell lines, respectively, and was comparable to the positive control, CA-4. Tubulin polymerization experiments indicated that 15e effectively inhibited the tubulin polymerization, and immunostaining assay revealed that it significantly disrupted tubulin microtubule dynamics. Moreover, cell cycle studies revealed that compound 15e dramatically arrested cell cycle progression at G2/M phase and caused microtubule destabilization. Molecular modeling studies showed that 15e could bind to the colchicine binding site on microtubules.

Ajuba overexpression regulates mitochondrial potential and glucose uptake through YAP/Bcl-xL/GLUT1 in human gastric cancer

Ajuba dysregulation has been reported in several human cancers. However, its expression patterns and biological roles in human gastric cancers have not yet been characterized. In the current study, we found that Ajuba protein was increased in gastric cancer tissues and in cell lines. High Ajuba expression positively correlated with the tumor-node-metastasis (TNM) stage, lymph node metastasis and poor prognosis. The Cancer Genome Atlas (TCGA) and Oncomine microarray data mining also suggested that Ajuba mRNA upregulation in gastric cancer tissues. We used SGC-7901 and NCI-N87 cell lines for Ajuba overexpression and siRNA knockdown respectively. MTT and colony formation assays indicated that Ajuba overexpression increased proliferation rate and colony formation ability while Ajuba siRNA inhibited proliferation rate and colony formation ability. AnnexinV and JC1 staining showed that Ajuba downregulated cisplatin induced apoptosis while it upregulated mitochondrial membrane potential. Ajuba overexpression also inhibited caspase-3 and PARP cleavage, while Ajuba depletion showed the opposite effects. Notably, Ajuba enhanced glucose metabolism by upregulating glucose uptake, glucose consumption, lactate production and ATP production. We further revealed that Ajuba positively regulated cyclin D1, Bcl-xL and GLUT1 at both mRNA and protein levels. Analysis of TCGA dataset revealed that there were positive correlations between Ajuba and cyclin D1, Bcl-xL, GLUT1 at the mRNA levels. Further investigation demonstrated that Ajuba overexpression inhibited Hippo signaling by upregulating YAP protein expression. Depletion of YAP by siRNA abolished the effect of Ajuba on cyclin D1, Bcl-xL and GLUT1. Together, our study showed that Ajuba was overexpressed in human gastric cancers, where it increased cell growth and chemoresistance. Our data also identified novel roles of Ajuba in gastric cancer progression involving regulating glucose uptake and mitochondrial function through the YAP-GLUT1/Bcl-xL axis, making it a potential therapeutic target.

Curcumin inhibits the lymphangiogenesis of gastric cancer cells by inhibiton of HMGB1/VEGF-D signaling.

Accumulating evidence shows that curcumin exerts antitumor activities in a variety of malignancies. High mobility group box 1 (HMGB1) is associated with vascular endothelial growth factor D (VEGF-D)–induced lymphangiogenesis and tumor metastasis in gastric cancer. However, the molecular mechanisms by which curcumin regulates HMGB1-mediated lymphangiogenesis in gastric cancer remain unclear. In this study, the cytotoxic effects of curcumin were investigated in gastric cancer AGS and SGC-7901 cell lines by MTT assay, and curcumin-induced morphological changes and cell apoptosis were assessed by using flow cytometry analysis and caspase-3 activity. The effects of curcumin on HMGB1 and VEGF-D expression were examined by reverse transcription polymerase chain reaction (RT-PCR) and western blot analysis. As a result, we found that curcumin decreased cell viability and caused a dose-dependent cell apoptosis through the activation of caspase-3. The mRNA and protein expression levels of HMGB1 and VEGF-D were significantly eliminated by curcumin administration. Pre-treatment with the recombinant HMGB1 (rHMGB1) markedly abolished curcumin-reduced VEGF-D expression. Our findings suggested that curcumin might exert anti-lymphangiogenesis in gastric cancer by inhibition of HMGB1/VEGF-D signaling.

Hydroxyl-substituted double Schiff-base condensed 4-piperidone/cyclohexanones as potential anticancer agents with biological evaluation

Novel hydroxyl-substituted double Schiff-base 4-piperidone/cyclohexanone derivatives, 3a–e, 4a–e, 5a–d, and 6a–c, were synthesized and fully characterized by 1H NMR, IR and elemental analysis. The cytotoxicity against human carcinoma cell lines A549, SGC7901, HePG2, HeLa, K562, THP-1 and non-malignant LO2 cell lines were evaluated. The results showed 4-piperidinone derivatives displayed better cytotoxicity than cyclohexanone derivatives, especially for 3,4,5-trihydroxyphenyl-substituted BAP 5c. The western blot and flow cytometry results proved 5c can effectively promote cell apoptosis through up-regulating Bax protein and down-regulating Bcl-2 protein expression. Molecular docking modes showed that 5c could reasonably bind to the active site of Bcl-2 protein through strong intermolecular hydrogen bonds and significant hydrophobic effect. In vivo, 5c can effectively suppress the growth of HepG2 xenografts without apparent body weight changes. This study indicates that 5c can be a potential anticancer agent for early treatment of liver cancers.

Two New Succinimide Derivatives Cladosporitins A and B from the Mangrove-derived Fungus Cladosporium sp. HNWSW-1.

Two new succinimide-containing derivatives, cladosporitins A (1) and B (2), were isolated from the fermentation cultures of the mangrove-derived fungus Cladosporium sp. HNWSW-1, along with a new pyrone, clapone (3), as well as the previously reported talaroconvolutin A (4) and anthraquinone (5). The structures of the isolated compounds were elucidated by 1D, 2D NMR, and HRMS spectral analysis. Compound 2 showed cytotoxicity against BEL-7042, K562 and SGC-7901 cell lines with IC50 values of 29.4 ± 0.35 μM, 25.6 ± 0.47 μM, and 41.7 ± 0.71 μM, respectively, whereas compound 4 exhibited cytotoxicity against Hela and BEL-7042 cell lines with IC50 values of 14.9 ± 0.21 μM and 26.7 ± 1.1 μM, respectively. In addition, compounds 4 and 5 displayed inhibitory activity against α-glycosidase, with IC50 values of 78.2 ± 2.1 μM and 49.3 ± 10.6 μM, respectively.

UHRF1 mediates cell migration and invasion of gastric cancer.

Gastric cancer (GC) is a common highly aggressive malignant tumor in worldwide. Ubiquitin-like with PHD and ring-finger protein 1 (UHRF1) has a key role in several kinds of cancers development. However, the biology effect of UHRF1 on the tumorigenesis of GC remains unclear. In this research, the role of UHRF1 in the growth, migration, invasion and apoptosis and the underlying mechanisms were investigated in MGC803 and SGC7901 cells. The UHRF1 knockdown MGC803 and SGC7901 cell lines were used to investigate the roles of UHRF1 on GC cell growth, migration, invasion and apoptosis. The growth, migration and invasion rate of UHRF1 knockdown cells was lower than that of the control. Moreover, ROS generation and caspase-3/caspase-9 activities increased in UHRF1 knockdown cells. And mitochondrial membrane potential decreased in UHRF1 knockdown cells. These findings indicated that UHRF1 promoted the growth, migration and invasion of MGC803 and SGC7901 cells and inhibited apoptosis via a ROS-associated pathway.

Corilagin induces apoptosis, autophagy and ROS generation in gastric cancer cells invitro.

Corilagin, a unique component of the tannin family, has been identified in several medicinal plants. In previous literature, corilagin exhibited a marked anticancer property in a variety of human cancer cells. However, the biological effects of corilagin on gastric cancer and the mechanisms involved remain to be fully elucidated. In the present study, it was reported that corilagin induced inhibition of cell growth in SGC7901 and BGC823 cells in a concentration-dependent manner. It was found that corilagin exhibited less toxicity towards normal GES-1 cells. Furthermore, the study showed that corilagin induced the apoptosis of gastric cancer cells mainly via activating caspase-8, -9, -3 and poly ADP-ribose polymerase proteins. Simultaneously, it was verified that corilagin triggered autophagy in gastric cancer cells and the inhibition of autophagy improved the activity of corilagin on cell growth suppression. In addition, corilagin significantly increased intracellular reactive oxygen species production, which is important in inhibiting the growth of gastric cancer cells. Finally, it was shown that necroptosis cannot be induced by corilagin-incubation in SGC7901 and BGC823 cell lines. Consequently, these findings indicate that corilagin may be developed as a potential therapeutic drug for gastric cancer.

Anticancer and antibacterial activity in vitro evaluation of iridium(III) polypyridyl complexes.

Three iridium(III) polypyridyl complexes [Ir(ppy)2(PYTA)](PF6) (1) (ppy = 2-phenylpyridine), [Ir(bzq)2(PYTA)](PF6) (2) (bzq = benzo[h]quinolone) and [Ir(piq)2(PYTA)](PF6) (3) (piq = 1-phenylisoquinoline, PYTA = 2,4-diamino-6-(2'-pyridyl)-1,3,5-triazine) were synthesized and characterized by elemental analysis, IR, 1H NMR and 13C NMR. The cytotoxic activity of the complexes toward cancer SGC-7901, Eca-109, A549, HeLa, HepG2, BEL-7402 and normal LO2 cell lines was investigated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Complex 3 shows the most effective on inhibiting the above cell growth among these complexes. The complexes locate at the lysosomes and mitochondria. AO/EB, Annex V and PI and comet assays indicate that the complexes can induce apoptosis in SGC-7901 cells. Intracellular ROS and mitochondrial membrane potential were examined under fluorescence microscopy. The results demonstrate that the complexes increase the intracellular ROS levels and induce a decrease in the mitochondrial membrane potential. The complexes can enhance intracellular Ca2+ concentration and cause a release of cytochrome c. The autophagy was studied using MDC staining and western blot. Complexes 1-3 can effectively inhibit the cell invasion with a concentration-dependent manner. Additionally, the complexes target tubules and inhibit the polymerization of tubules. The antimicrobial activity of the complexes against S. aureus, E. coli, Salmonella and L. monocytogenes was explored. The mechanism shows that the complexes induce apoptosis in SGC-7901 cells through ROS-mediated lysosomal-mitochondrial, targeting tubules and damage DNA pathways. Three iridium(III) complexes [Ir(N-C)2(PYTA)](PF6) (N-C = ppy, 1; bzq, 2; piq, 3) were synthesized and characterized. The anticancer activity of the complexes against SGC-7901 cells was studied by apoptosis, comet assay, autophagy, ROS, mitochondrial membrane potential, intracellular Ca2+ levels, release of cytochrome c, tubules and western blot analysis. The antibacterial activity in vitro was also assayed.

An investigation of the effect of hyperthermia using iron and magnetic nanoparticles in cancer treatment

Introduction: hyperthermia using different methods such as microwave and magnetic waves is one of the methods to treat cancer. In this method, iron and magnetic nanoparticles are used to increase the temperature and increase the effect of hyperthermia as auxiliary treatment with chemotherapy and radiotherapy. In this study, the role of iron and magnetic nanoparticles have been compared in increasing the tumor temperature and maintaining healthy tissue and thus increasing the efficiency of hyperthermia with radiotherapy. Materials and Methods: After cultivating and proliferating SGC-7901 cell line derived from gastric cancer, iron and magnetic nanoparticles were injected into tumors separately in two different groups, using microwave and magnetic waves irradiation their temperature was increased to upper than 43 ° C, and then 48 hours after irradiation, cell survival was evaluated using MTT method to investigate the effect of iron and magnetic nanoparticles. Results: Cell survival was achieved as a result of hyperthermia and radiotherapy in the presence of metal and magnetic nanoparticles 18% and 21% respectively. Conclusion: The presence of both groups of iron and magnetic nanoparticles during microwave and magnetism waves irradiation increased cell death in cultured cells. The results of our study showed that iron nanoparticles are less concentrated in comparison to magnetic ones, causing a rapid rise in temperature, which increases the efficiency of hyperthermia and reduces damage to healthy tissues around the tumor.

New transformation pathway and cytotoxic derivatives from the acid hydrolysis of timosaponin B III

Timosaponin B III is a major bioactive steroidal saponin isolated from Anemarrhena asphodeloides Bge. To potentially discover derivatives with better biological activity, timosaponin B III was structurally modified via acid hydrolysis to yield one new (2, timopregnane A I) C21 steroidal glycoside and seven known compounds. Their structures were elucidated on the basis of NMR spectroscopy and mass spectrometry. All eight compounds were evaluated for cytotoxic activity against MCF7, SW480, HepG2, and SGC7901 cell lines in vitro. As a result, compounds 6 and 7 showed significant activity (IC50 2.94–12.2 μM) against all tested cell lines. Structure–activity relationships of these compounds were investigated and the preliminary conclusions were provided. Moreover, a new transformation pathway was discovered in the acid hydrolysis of timosaponin B III for the first time.

IFT80 Improves Invasion Ability in Gastric Cancer Cell Line via ift80/p75NGFR/MMP9 Signaling.

The assembly and maintenance of cilia depend on intraflagellar transport (IFT) proteins, which play an important role in development and homeostasis. IFT80 is a newly defined IFT protein and partial mutation of IFT80 in humans causes diseases such as Jeune asphyxiating thoracic dystrophy (JATD) and short rib polydactyly (SRP) type III, both characterized by abnormal skeletal development. However, the role and mechanism of IFT80 in the invasion of gastric cancer is unknown. We established SGC-7901 and MKN-45 gastric cancer cell lines that stably overexpressed IFT80, as verified by quantitative reverse transcription-PCR, Western blot, and immunofluorescence. Matrix metalloproteinase-9 (MMP9) plays an important role in tumor invasion, and its expression was assessed by quantitative reverse transcription-PCR, Western blotting, and immunofluorescence. The invasion ability of IFT80 on SGC-7901 and MKN-45 cells was examined by the Matrigel invasion assay. The relationship between p75NGFR, and the p75NGFR antagonists, PD90780 and IFT80, were detected by quantitative reverse transcription-PCR and Western blotting. We first detected an IFT80 expression pattern, and found that IFT80 was highly expressed in gastric cancer clinical samples. Overexpression of IFT80 in the gastric cancer cell lines, SGC-7901 and MKN-45, led to lengthening cilia. Additionally, overexpression of IFT80 significantly improved proliferation and invasion, but inhibited apoptosis, in gastric cancer cells. We further found that overexpression of IFT80 increased p75NGFR and MMP9 mRNA and protein expression. Treatment with the p75NGFR antagonist PD90780 inhibited the increased invasion ability resulting from overexpression of IFT80 in SGC-7901 and MKN-45 gastric cancer cells. Thus, these results suggest that IFT80 plays an important role in invasion of gastric cancer through regulating the ift80/p75NGFR/MMP9 signal pathways.

Long Noncoding RNA GMAN, Up-regulated in Gastric Cancer Tissues, Is Associated With Metastasis in Patients and Promotes Translation of Ephrin A1 by Competitively Binding GMAN-AS

We aimed to identify long noncoding RNAs (lncRNAs) that are up-regulated in gastric cancer tissues from patients and study their function in gastric tumor metastasis. We collected gastric tumor and nontumor tissues from patients in China and analyzed levels of lncRNAs by microarray analysis, proteins by immunohistochemistry, and RNAs by quantitative reverse-transcription polymerase chain reaction; we compared these with survival times of patients and tumor progression. RNA levels were knocked down or knocked out in BGC-823, SGC-7901, and MKN45 cell lines using small interfering or short hairpin RNAs or clustered regularly interspaced short palindromic repeats (ie, CRISPR)/CRISPR associated protein 9 (ie, Cas9) vectors. Genes were overexpressed from transfected plasmids in HGC-27 cells. Cells were analyzed by Northern blot and immunoblot, polysome profiling assay, and cell invasion assay. Cells were injected into the tail veins or spleens of nude mice or SCID mice; lung and liver tissues were collected, and metastases were counted. lncRNAs were cloned by using rapid amplification of complementary DNA ends. Their interactions with other genes were determined by RNA pulldown and mapping assays. In microarray analyses, we identified 151 lncRNAs expressed at significantly higher levels in gastric tumor vs nontumor tissues. Levels of an lncRNA that we called gastric cancer metastasis associated long noncoding RNA (GMAN) were increased in gastric tumor tissues, compared with nontumor tissues; its up-regulation was associated with tumor metastasis and shorter survival times of patients. The GMAN gene overlaps with the ephrin A1 gene (EFNA1) and was highly expressed in BGC-823 and MKN45 cells. Knockdown of GMAN in these cells did not affect proliferation, colony formation, or adhesion but did reduce their invasive activity in Transwell assays. Ectopic expression of GMAN increased the invasive activity of HGC-27 cells. BGC-823 and MKN45 cells with knockdown of GMAN formed fewer metastases after injection into tail veins of nude mice. Knockdown or knockout of GMAN also reduced levels of ephrin A1 protein in cells. We found that GMAN promoted translation of ephrin A1 messenger RNA into protein by binding to the antisense GMAN RNA (GMAN-AS)-this antisense sequence is also complementary to that of ephrin A1 mRNA. Levels of ephrin A1 protein were also increased in gastric tumors from patients with metastases than in those without metastases. Knockout of ephrin A1 in BGC-823 cells reduced their invasive activity in Transwell assays and ability to form metastases after injection into SCID mice. Ectopic expression of ephrin A1 in BGC-823 cells with knockdown or knockout of GMAN restored their invasive activities and ability form metastases in nude or SCID mice. A CRISPR/Cas9-based strategy to disrupt the GMAN gene significantly reduced the numbers of metastases formed from SGC-7901 cells in mice. We identified an lncRNA, which we call GMAN, that is increased in gastric tumors from patients and associated with survival and formation of metastases. It regulates translation of ephrin A1 mRNA by binding competitively to GMAN-AS. Knockdown or knockout of GMAN or ephrin A1 in gastric cancer cell lines reduces their invasive activity and ability to form metastases after injection into mice. These genes might be targeted to prevent or reduce gastric cancer metastasis.

Corrigendum] Netrin‑1 induces the proliferation of gastric cancer cells via the ERK/MAPK signaling pathway and FAK activation.

During the preparation of the figures in the above article, the authors inadvertently selected images for the shCTL experiments portrayed in Fig.5I andJ (for the MGC803 and SGC7901cell lines, respectively) that were generated from the same original data source. A corrected version of Fig.5 is shown opposite, showing the correct data for the shCTL experiment performed in SGC7901cells (Fig.5J). This error did not affect the major conclusions reported in the paper. All the authors have agreed to this Corrigendum. The authors regret this error, and apologize for any confusion that it may have caused. [the original article was published in Oncol Rep40: 2325‑2333, 2018; DOI: 10.3892/or.2018.6614].

Down-regulation of E26 transformation-specific homologous factor expression inhibits the growth of gastric cancer cells

Objective To observe the effect of down-regulation of E26 transformation-specific homologous factor (EHF) expression on the growth of gastric cancer cells. Methods Western blotting and real-time quantitative reverse transcriptase-polymerase chain reaction (RT-qPCR) were used to detect the expression of EHF protein and mRNA in gastric cancer cell lines BGC823, SGC7901 and gastric mucosal epithelial cell line GES-1, respectively. Using the small interfering RNA (siRNA) interference technology, si-EHF-979 or control siRNA si-NC was transfected into gastric cancer cells BGC823 and SGC7901. The si-EHF-979 transfection group served as experimental group, and si-NC transfection group as control group. The methyl thiazol tetrazolium (MTT) assay was utilized to detect the proliferation of gastric cancer cells. The effect of EHF on the migration and invasion of gastric cancer cells was measured by Transwell assay. The gastric cancer cell BGC823 transfected with si-EHF-979 or si-NC was inoculated into the right axilla of nude mice to establish a nude mouse exenograft model. Results Compared with GES-1 cells, the expression levels of EHF in BGC823 and SGC7901 cells were significantly up-regulated, with the difference being statistically significant (P=0.001). The ability of gastric cancer cells to proliferate, migrate and invade after EHF gene knockdown was significantly inhibited. The nude mouse xenograft model showed that knockdown of EHF expression significantly inhibited tumor growth in vivo, the difference was statistically significant (P=0.001). Conclusion EHF is highly expressed in gastric cancer cell lines. Knockdown of EHF expression can inhibit the proliferation of gastric cancer cells. Key words: Gastric cancer; E26 transformation-specific homologous factor; Cell proliferation; Cell migration

Chemical constituents from roots and rhizomes of Rubia oncotricha and their cytotoxic activities

Fourteen compounds, including rubiprasin D (1), rubiprasin B (2), rubiprasin C (3), oleanolic acid (4), methyl-5-hydroxy-dinaphtho[1, 2-2'3']furan-7, 12-dione-6-carboxylate (5), rubioncolin C (6), mollugin (7), furomollugin (8), 3-amino-2-methoxycarbonyl-1, 4-naphthoquinone (9), 1-hydroxy-2-methyl-9, 10-anthraquinone (10), 2-hydroxy-6-methyl-9, 10-anthraquinone (11), 1, 4-dihydroxy-2-hydroxymethyl-9, 10-anthraquinone (12), 2-hydroxy-1-methoxy-9, 10-anthraquinone (13), and 1-hydroxy-2-methoxy-6-methyl-9, 10-anthraquinone(14), were isolated from the methanol extract of the roots and rhizomes of Rubia oncotricha using various column chromatographies. Their structures were mainly determined on basis of NMR and MS spectroscopic data analyses. Among them, 1 is a new oleanane triterpene, and compounds 2-5, 9 and 11-13 were obtained from this plant for the first time. Cytotoxic and nematicidal activities of all these compounds were evaluated, and the results showed that only 4, 6, 11 and 12 exhibited cytotoxicities against A549, SGC-7901 and HeLa cancer cell lines. The IC₅₀ of 6 were 19.42, 2.74, 8.07 μmol·L⁻¹, respectively.

Hydrogen sulfide releasing enmein-type diterpenoid derivatives as apoptosis inducers through mitochondria-related pathways

In this study, we combined two enemin-type diterpenoid derivatives with two well-established hydrogen sulfide moieties via ester or different anhydride linkers, to search apoptosis inducing drug candidate capable of hydrogen sulfide generating. Therefore, a series of hybrids were synthesized and superior antiproliferative efficacy accompanied with enhanced selectivity was observed under extensive pharmacological evaluations. A standard methylene blue (MB+) method was applied to measure the capacity for the hydrogen sulfide generation of all the target derivatives. One particular molecule A1, which contained α-thioctic acid moiety for hydrogen sulfide donating, manifested more potent antiproliferative activity. It exerted inhibitory effects against Bel-7402, SGC-7901 and A549 cell lines with IC50 values of 2.16, 5.07 and 6.98 μM respectively. While it exacted relatively low effects over human normal cell lines L-02 and PBMC with IC50 values of 15.81 μM for the prior and 14.15 μM for the latter, and displayed better selectivity index (SI) than parent diterpenoids. A high dosage of H2S release was also recorded. Hence, A1 was most suitable for mechanistic exploration on account of both safety and efficacy. The ensuing biological assays revealed central role of apoptosis in A1’s mode of action for antiproliferative efficacy, which led to further confirmation of G1 phase cell cycle arrest, mitochondria membrane potential collapse and apoptotic activation in Bel-7402 cells. Further western blot assay on intrinsic mitochondria pathway unlocked intricate interplay among a series of apoptotic related proteins in which Bax, caspase-3 and cytochrome c went through up-regulation, while Bcl-2, Bcl-xL and procaspase-3 undergone down-regulation. In a nutshell, a hydrogen sulfide releasing hybrid A1 was synthesized and antiproliferative evaluation identified it to be a worthy drug candidate for future in depth study.

TCF21 inhibits proliferation and chemoresistance through the AKT pathway in human gastric cancer

In a previous study, we showed that transcription factor 21 (TCF21) is methylated and downregulated in human gastric cancer samples and serves as an independent prognostic factor. However, its biological role and potential mechanism in gastric cancer cells remain unexplored. In the current study, we examined TCF21 expression in 6 gastric cancer cell lines. The BGC-823 and SGC-7901 cell lines were selected for small interfering RNA and plasmid transfection, respectively. The results of the Cell Counting Kit-8 assay demonstrated that TCF21 inhibited gastric cancer cell proliferation. Cell cycle analysis suggested that TCF21 inhibited cell cycle progression in gastric cancer cells. The Matrigel invasion assay demonstrated that TCF21 negatively regulated invasion. The cell adhesion assay showed that TCF21 increased cell adhesion. Gastric cancer cells were treated with cisplatin to explore the role of TCF21 in chemoresistance. Cell Counting Kit-8 assay and AnnexinV/propidium iodide analyses showed that TCF21 overexpression sensitized SGC-7901 cells to cisplatin, whereas its depletion reduced sensitivity in BGC-823 cells. JC-1 staining was performed to measure the effect of TCF21 on mitochondrial potential. TCF21 downregulated mitochondrial membrane potential after treatment with cisplatin. Western blot analysis showed that TCF21 overexpression negatively regulated Bcl-xL, phosphorylated extracellular signal regulated kinase, and phosphorylated AKT expression and induced caspase 3 cleavage. LY294002, an AKT inhibitor, blocked the effect of TCF21 on Bcl-xL, caspase 3 and CDDP-induced apoptosis. Nude mice experiments demonstrated that TCF21 inhibited gastric cancer growth in vivo. In conclusion, our results suggest that TCF21 inhibits gastric cancer growth and chemoresistance possibly through the AKT signaling pathway.

Pyrazolo[4,3-b]pyrimido[4,5-e][1,4]diazepine derivatives as new multi-targeted inhibitors of Aurora A/B and KDR

Aurora A, Aurora B and Kinase Insert Domain-containing Receptor (KDR) play essential roles in sustained cancer growth. In the present study, eighteen pyrazolo[4,3-b]pyrimido[4,5-e][1,4]diazepine derivatives were designed and synthesized. Most of the prepared compounds exhibited obviously enzymatic (Aurora A/B and KDR) activities. Among these analogs, compound 17g displayed significant Aurora A/B and KDR potencies with IC50 values of 46.2 nM, 37.6 nM and 21.6 nM, respectively. The results of further biological assays showed that compound 17g possessed moderate anti-proliferative activities against SNU-5, MKN-45 and MKN-74 cells lines, induced G2/M cell cycle arrest and apoptosis in MKN-45, MKN-74, SGC-7901 and SNU-5 cell lines, provided acceptable pharmacokinetic profiles (F = 63.8%), and inhibited the proliferation of SNU-5 tumors in vivo of mice. All of the above results suggested that pyrazolo[4,3-b]pyrimido[4,5-e][1,4]diazepine could be developed as a promising scaffold of multiple Aurora A/B and KDR inhibitors and 17g was worth of further research as a multi-targeted lead compound.