Affect Cell Cycle Distribution Research Articles

Exploring the Antiproliferative and Modulatory Effects of 1-Methoxyisobrassinin on Ovarian Cancer Cells: Insights into Cell Cycle Regulation, Apoptosis, Autophagy, and Its Interactions with NAC.

Ovarian cancer, a highly lethal malignancy among reproductive organ cancers, poses a significant challenge with its high mortality rate, particularly in advanced-stage cases resistant to platinum-based chemotherapy. This study explores the potential therapeutic efficacy of 1-methoxyisobrassinin (MB-591), a derivative of indole phytoalexins found in Cruciferae family plants, on both cisplatin-sensitive (A2780) and cisplatin-resistant ovarian cancer cells (A2780 cis). The findings reveal that MB-591 exhibits an antiproliferative effect on both cell lines, with significantly increased potency against cisplatin-sensitive cells. The substance induces alterations in the distribution of the cell cycle, particularly in the S and G2/M phases, accompanied by changes in key regulatory proteins. Moreover, MB-591 triggers apoptosis in both cell lines, involving caspase-9 cleavage, PARP cleavage induction, and DNA damage, accompanied by the generation of reactive oxygen species (ROS) and mitochondrial dysfunction. Notably, the substance selectively induces autophagy in cisplatin-resistant cells, suggesting potential targeted therapeutic applications. The study further explores the interplay between MB-591 and antioxidant N-acetylcysteine (NAC), in modulating cellular processes. NAC demonstrates a protective effect against MB-591-induced cytotoxicity, affecting cell cycle distribution and apoptosis-related proteins. Additionally, NAC exhibits inhibitory effects on autophagy initiation in cisplatin-resistant cells, suggesting its potential role in overcoming resistance mechanisms.

Bisphenol S and F affect cell cycle distribution and steroidogenic activity of human ovarian granulosa cells, but not primary granulosa tumour cells

Bisphenol S (BPS) and F (BPF), a new generation of bisphenols (BPs), are the main substitutes for bisphenol A (BPA). Both have been detected in human body fluids. Importantly, bisphenols are structurally similar to oestrogen, the main sex hormone in females. Because bisphenols bind to nuclear oestrogen receptors (ESR1 and ESR2) and to membrane G-coupled receptor 30 (GPR30), they can disrupt ovarian function. Here, we reveal the molecular mechanism underlying the effects of BPS and BPF on the cell cycle and steroidogenesis in the human ovarian granulosa cell (GC) line HGrC1. We show that BPS and BPF arrest GCs at the G0/G1 phase by inducing expression of cyclin D2, an important event that triggers maximal steroid synthesis in response to the BPS and BPF. We used pharmacological inhibitors to show that BPS and BPF, despite acting via already described pathways, also stimulate steroid secretion via IGF1R pathways in HGrC1 cells. Moreover, we identified differences critical to bisphenols response between normal (HGrC1) and primary tumour granulosa (COV434) cells, that enable COV434 cells to be more resistant to bisphenols. Overall, the data suggest that BPS and BPF drive steroidogenesis in human ovarian GCs by affecting the cell cycle. Furthermore, the results indicate that BPS and BPF act not only via the classical and non-classical ESR pathways, but also via the IGF1R pathway.

Immobilization of Olive Leaf Extract with Chitosan Nanoparticles as an Adjunct to Enhance Cytotoxicity.

We immobilized the olive leaf extract (OLE) with chitosan nanoparticles (CNPs) by optimizing the effect of various immobilization conditions, and OLE-loaded CNPs (OLE-CNPs) were then elaborately characterized physicochemically by scanning electron microscopy (SEM), Fourier transform infrared (FT-IR) spectroscopy, dynamic light scattering (DLS), and atomic force microscopy (AFM). Under optimal conditions, CNPs were able to accommodate the OLE with a loading capacity of 97.5%. The resulting OLE-CNPs had a spherical morphology, and their average diameter was approximately 100 nm. The cytotoxic influence, cell cycle distribution, and apoptosis stage of OLE and OLE-CNPs were analyzed on lung carcinoma (A549) and breast adenocarcinoma (MCF-7) cell lines. In an in vitro cytotoxic assay, IC50 values of OLE-CNPs were determined to be 540 μg/mL for A549 and 810 μg/mL for MCF-7. The treatment of both A549 and MCF-7 with OLE-CNPs caused the highest cell arrest in G0/G1 in a dose-independent manner. OLE-CNPs affected cell cycle distribution in a manner different from free OLE treatment in both cancer cells. A549 and MCF-7 cells were predominantly found in the late apoptosis and necrosis phases, respectively, upon treatment of 1000 μM OLE-CNPs. Our results suggest that CNPs enhance the utility of OLEs as nutraceuticals in cancer and that OLE-CNPs can be utilized as an adjunct to cancer therapy.

Combinations of PRI-724 Wnt/β-Catenin Pathway Inhibitor with Vismodegib, Erlotinib, or HS-173 Synergistically Inhibit Head and Neck Squamous Cancer Cells.

The Wnt/β-catenin, EGFR, and PI3K pathways frequently undergo upregulation in head and neck squamous carcinoma (HNSCC) cells. Moreover, the Wnt/β-catenin pathway together with Hedgehog (Hh) signaling regulate the activity of cancer stem cells (CSCs). The aim of this study was to investigate the effects of the combinatorial use of the Wnt/β-catenin and Hh pathway inhibitors on viability, cell cycle progression, apoptosis induction, cell migration, and expression of CSC markers in tongue (CAL 27) and hypopharynx (FaDu) cancer cells. Co-inhibition of Wnt signaling with EGFR or PI3K pathways was additionally tested. The cells were treated with selective inhibitors of signaling pathways: Wnt/β-catenin (PRI-724), Hh (vismodegib), EGFR (erlotinib), and PI3K (HS-173). Cell viability was evaluated by the resazurin assay. Cell cycle progression and apoptosis induction were tested by flow cytometric analysis after staining with propidium iodide and Annexin V, respectively. Cell migration was detected by the scratch assay and CSC marker expression by the R-T PCR method. Mixtures of PRI-724 and vismodegib affected cell cycle distribution, greatly reduced cell migration, and downregulated the transcript level of CSC markers, especially POU5F1 encoding OCT4. Combinations of PRI-724 with erlotinib or HS-173 were more potent in inducing apoptosis.

Hsa_circ_0136839 regulates the malignant phenotypes of nasopharyngeal carcinoma via the Wnt/β-catenin signaling pathway.

With the development of RNA sequencing (RNA-seq) technology, circular RNA (circRNA), a new class of RNA, has received much attention in cancer research. However, information available on the biogenesis and functional value of circRNAs in nasopharyngeal carcinoma (NPC) is scarce. In the present study, we screened the circRNA profile of the NPC cell line C666-1 compared with that of the normal control NP69 by RNA-seq and identified a novel and relatively higher expressed circRNA, hsa_circ_0136839. Hsa_circ_0136839 was markedly downregulated in NPC tissues, as confirmed by quantitative reverse transcription polymerase chain reaction. Functional in vitro studies revealed that hsa_circ_0136839 knockdown in C666-1 cell notably promoted cell proliferation, migration, and invasion abilities, as well as affected cell cycle distribution with an S-phase arrest. However, hsa_circ_0136839 overexpression in CNE2 cells resulted in an opposite response. Mechanistically, we demonstrated that aberrant hsa_circ_0136839 expression might affect the malignant phenotypes of NPC cells by activating the wnt/β-catenin signaling pathway. Thus, our findings contribute to further the understanding of NPC pathogenesis and provide new ideas for NPC clinical diagnosis and treatment.

Nuclear-targeted EGF receptor enhances proliferation and migration of human anaplastic thyroid cancer cells.

Epidermal growth factor (EGF) has various important physiological functions, which it exerts by binding to the epidermal growth factor receptor (EGFR). Reports show that EGF expression is strongly correlated with the occurrence and development of many types of tumour. To date, however, the relationship between EGF/EGFR and the occurrence and development of thyroid carcinoma remains unclear. In the current study, we investigated this phenomenon using human anaplastic thyroid carcinoma cell lines (SUN-80). The results indicated that EGF triggered the EGFR-mediated intracellular signalling pathway, including signal transducers and activators of transcription 1/3/5 (STAT1/3/5) and protein kinase B (AKT) in a time- and dose-dependent manner. In addition, results from EGF-induced EGFR internalization and co-localization analyses showed that clathrin, Rab5/7, and EEA1 play critical roles in the intracellular trafficking of EGF/EGFR. Interestingly, EGF triggered EGFR translocation into the nucleus, while nuclear-localized EGFR affected cell cycle distribution, thereby significantly promoting the ration of S phase. Overall, these findings indicated that nuclear EGFR exerts biological activity and physiological functions, including changing cell cycle, which in turn promotes proliferation and migration of SUN-80 cells. These findings lay a foundation for further explorations seeking to understand the biological effects of the EGF/EGFR system on the occurrence and development of thyroid cancer.

Synthesis and Biological Evaluation of Novel 2-imino-4-thiazolidinones as Potential Antitumor Agents for Glioblastoma.

The purpose of our study was to explore the molecular hybridization between 2- imino-4-thizolidione and piridinic scaffolds and its potential antitumor activity. Glioblastoma is the most aggressive glioma tumor clinically diagnosed malignant and highly recurrent primary brain tumor type. The standard of treatment for a glioblastoma is surgery, followed by radiation and chemotherapy using temozolomide. However, the chemoresistance has become the main barrier to treatment success. 2-imino-4-thiazolidinones are an important class of heterocyclic compounds that feature anticancer activity; however the antiglioblastoma activity is yet to be explored. To synthesize and characterize a series of novel 2-imino-4-thiazolidinones and evaluate their antiglioblastoma activity. The 2-imino-4-thiazolidinone (5a-p) was synthesized according to the literature with modifications. Compounds were identified and characterized using spectroscopic analysis and X-ray diffraction. The antitumor activity was analyzed by 3-(4,5- dimethyl)-2,5-diphenyltetrazolium bromide (MTT) assay both in primary astrocyte and glioma (C6). Apoptosis and cell cycle phase were determined by flow cytometry analysis. The expression of caspase-3/7 was measured by luminescence assay. Oxidative stress parameters as: Determination of Reactive Oxygen Species (ROS), Superoxide Dismutase (SOD) activity, Catalase (CAT) activity and total sulfhydryl content quantification were analyzed by colorimetric assays according to literature. Among sixteen synthesized compounds, three displayed potent antitumor activities against tested glioblastoma cell line showed IC50 values well below the standard drug temozolomide. Therefore, compounds 5a, 5l and 5p were evaluated using cell cycle and death analysis, due to potent toxicity (2.17±1.17, 6.24±0.59, 2.93±1.12μM, respectively) in C6 cell line. The mechanism of action studies demonstrated that 5a and 5l induced apoptosis significantly increase the percentage of cells in Sub-G1 phase in the absence of necrosis. Consistent with these results, caspase-3/7 assay revealed that 5l presents pro-apoptotic activity due to the significant stimulation of caspases-3/7. Moreover, 5a, 5l and 5p increased antioxidant defense and decreased reactive oxygen species (ROS) production. The compounds were synthesized with good yield and three of these presented (5a, 5l and 5p) good cytotoxicity against C6 cell line. Both affected cell cycle distribution via arresting more C6 cell line at Sub-G1 phase promoting apoptosis. Furthermore, 5a, 5l and 5p modulated redox status. These findings suggest that these compounds can be considered as promising lead molecules for further development of potential antitumor agents.

AMPK increases expression of ATM through transcriptional factor Sp1 and induces radioresistance under severe hypoxia in glioblastoma cell lines

We have previously reported that severe hypoxia increases expression and activity of the DNA damage sensor ATM by activation of the key energy sensor AMPK. Here, to elucidate molecular mechanisms underlying increased expression and activity of ATM by AMPK under severe hypoxia, we investigated roles of transcriptional factors Sp1 and FoxO3a using human glioblastoma cell lines T98G and A172. Severe hypoxia increased expression of ATM, AMPKα and Sp1 but not that of FoxO3a. Knockdown of AMPKα suppressed expression of ATM and Sp1 and suppressed cellular radioresistance under severe hypoxia without affecting cell cycle distribution. Knockdown of Sp1 suppressed expression of ATM. These results suggest that increased expression and activity of AMPK under severe hypoxia induce cellular radioresistance through AMPK/Sp1/ATM pathway.

ASF1B Promotes Oncogenesis in Lung Adenocarcinoma and Other Cancer Types.

Anti-silencing function 1B histone chaperone (ASF1B) is known to be an important modulator of oncogenic processes, yet its role in lung adenocarcinoma (LUAD) remains to be defined. In this study, an integrated assessment of The Cancer Genome Atlas (TCGA) and genotype-tissue expression (GTEx) datasets revealed the overexpression of ASF1B in all analyzed cancer types other than LAML. Genetic, epigenetic, microsatellite instability (MSI), and tumor mutational burden (TMB) analysis showed that ASF1B was regulated by single or multiple factors. Kaplan-Meier survival curves suggested that elevated ASF1B expression was associated with better or worse survival in a cancer type-dependent manner. The CIBERSORT algorithm was used to evaluate immune microenvironment composition, and distinct correlations between ASF1B expression and immune cell infiltration were evident when comparing tumor and normal tissue samples. Gene set enrichment analysis (GSEA) indicated that ASF1B was associated with proliferation- and immunity-related pathways. Knocking down ASF1B impaired the proliferation, affected cell cycle distribution, and induced cell apoptosis in LUAD cell lines. In contrast, ASF1B overexpression had no impact on the malignant characteristics of LUAD cells. At the mechanistic level, ASF1B served as an indirect regulator of DNA Polymerase Epsilon 3, Accessory Subunit (POLE3), CDC28 protein kinase regulatory subunit 1(CKS1B), Dihydrofolate reductase (DHFR), as established through proteomic profiling and Immunoprecipitation-Mass Spectrometry (IP-MS) analyses. Overall, these data suggested that ASF1B serves as a tumor promoter and potential target for cancer therapy and provided us with clues to better understand the importance of ASF1B in many types of cancer.

Preclinical Anti-Lymphoma Activity of the BCL-2 BH4 Domain Antagonist Bda-366 in Mantle Cell Lymphoma

Mantle cell lymphoma (MCL) is an aggressive and incurable B-cell non-Hodgkin lymphoma. MCL is genetically characterized by t(11;14) translocation, which leads to cyclin D1 overexpression. Despite the introduction of high-dose chemotherapy followed by autologous stem cell transplantation and novel agents including the Bruton's tyrosine kinase inhibitor ibrutinib, the proteasome inhibitor bortezomib and the immunomodulator lenalidomide, MCL still remains an incurable disease. BCL-2 is often amplified and/or overexpressed in MCL; high-level copy number gains of the BCL2 locus at 18q21.3 are most frequent. The novel BCL-2BH4 domain antagonist BDA-366 converts anti-apoptotic BCL-2 into the pro-apoptotic molecule (Han et al., Cancer Cell 2015). Considering the promising clinical activity of the BH3 mimetics venetoclax (Davids et al., JCO 2017), we investigated anti-lymphoma effects of BDA-366 in MCL. A total of eight MCL cell lines (Z-138, JVM-2, Granta-519, MINO, JeKo-1, REC-1, MAVER-1 and NCEB-1) were used. Z-138, Granta-519, MINO and NCEB-1 have high-level DNA amplification of BCL-2 . BDA-366 induced dose- and time-dependent phosphatidylserine externalization in MCL cells, with 72-h ED50 (effective concentration inducing 50% cell killing as measured by annexin V positivity) values ranging from 9.3 to 240 nM. 72-h IC50 values (concentration at which cell growth is inhibited by 50%) were also determined, which ranged from 5 to 30 nM. BDA-366 showed smaller differences in sensitivity than venetoclax, raising the possibility that BDA-366 may exhibit broader anti-lymphoma activity against heterogeneous MCL backgrounds. Basal levels of BCL-2 (determined by flow cytometry) did not significantly affect MCL cell susceptibility (ED50) to BDA-366 (r = -0.08, P = 0.85). The presence of high-level DNA amplification of BCL-2 was not associated with BDA-366 sensitivity either. BDA-366 did not increase total BCL-2 levels but it actively promoted the exposure of pro-apoptotic BH3 domain of BCL-2, supporting its proposed mode of action. BDA-366 did not significantly affect cell cycle distribution; S and G2/M phase cells appeared to be susceptible to BDA-366-induced apoptosis. BDA-366 induced loss of mitochondrial membrane potential, caspase-3 cleavage and BAX activation, indicating mitochondrial apoptosis. p53 knockdown (>85% knockdown efficiencies, as determined by Western blotting) desensitized p53 wild-type cell lines Z-138 and JVM-2 to BDA-366 (ED50 values of 29 nM and 10 nM in Z-138; 303 nM and 108 nM in JVM-2), implying the interference of p53 with BCL-2 signaling. BDA-366 synergized with venetoclax to induce apoptosis in venetoclax-sensitive Z-138 (averaged combination index (aCI) = 0.25) and MINO cells (aCI = 0.14), indicating that the combination may abrogate BCL-2-mediated survival signaling in MCL. The combination effects of BDA-366 with doxorubicin or AraC were additive (aCI ~ 1.0). BDA-366 induced apoptosis in primary leukemia cells from patients with B-cell chronic lymphoproliferative disorders. BDA-366 appeared to take longer time to fully induce apoptosis than ABT-199, perhaps reflecting the distinct mode of action of BDA-366 that changes BCL-2 conformation. From a clinical viewpoint, the slower pharmacodynamics in inhibiting BCL-2 and inducing MCL cell death may reduce the risk of tumor lysis syndromes in patients receiving BDA-366. Collectively, BCL-2 BH4 inhibition may offer a novel therapeutic strategy for MCL. DisclosuresNo relevant conflicts of interest to declare.

HTERT Downregulation Attenuates Resistance to DOX, Impairs FAK-Mediated Adhesion, and Leads to Autophagy Induction in Breast Cancer Cells.

Telomerase is known to contribute to telomere maintenance and to provide cancer cell immortality. However, numerous reports are showing that the function of the enzyme goes far beyond chromosome ends. The study aimed to explore how telomerase downregulation in MCF7 and MDA-MB-231 breast cancer cells affects their ability to survive. Consequently, sensitivity to drug resistance, proliferation, and adhesion were assessed. The lentiviral-mediated human telomerase reverse transcriptase (hTERT) downregulation efficiency was performed at gene expression and protein level using qPCR and Western blot, respectively. Telomerase activity was evaluated using the Telomeric Repeat Amplification Protocol (TRAP) assay. The study revealed that hTERT downregulation led to an increased sensitivity of breast cancer cells to doxorubicin which was demonstrated in MTT and clonogenic assays. During a long-term doubling time assessment, a decreased population doubling level was observed. Interestingly, it did not dramatically affect cell cycle distribution. hTERT downregulation was accompanied by an alteration in β1-integrin- and by focal adhesion kinase (FAK)-driven pathways together with the reduction of target proteins phosphorylation, i.e., paxillin and c-Src. Additionally, autophagy activation was observed in MDA-MB-231 cells manifested by alternations in Atg5, Beclin 1, LC3II/I ratio, and p62. These results provide new evidence supporting the possible therapeutic potential of telomerase downregulation leading to induction of autophagy and cancer cells elimination.

Fra-1 Inhibits Cell Growth and the Warburg Effect in Cervical Cancer Cells via STAT1 Regulation of the p53 Signaling Pathway.

The oncogenesis of cervical cancer is a multi-factor and multi-step process, and major risk factors include oncogene activation with tumor suppressor gene inactivation, viral factors, and immune factors. For example, the human papillomavirus (HPV) has been linked to the occurrence of cervical cancer. At present, the pathogenesis of cervical cancer remains unclear. Fra-1 (Fos-related antigen 1, also known as FOSL1) is a member of the Fos family and an important nuclear transcription factor that regulates normal cell growth, differentiation, and apoptosis. In the present study, we found that Fra-1 inhibited the proliferation of cervical cancer cells while also promoting apoptosis and affecting cell cycle distribution. Moreover, Fra-1 up-regulated STAT1 expression and modulated p53 signal pathway activity in cervical cancer cells. Overexpression of Fra-1 inhibited cell senescence by altering sirtuin 1 (SIRT1) expression in HeLa cells, and Fra-1 overexpression restored mitochondrial disorder and suppressed metabolic reprogramming in HeLa cells. Silencing of STAT1 impaired the inhibitory effect of Fra-1 on cervical cancer cell growth, while knock-down of STAT1 reversed the effect on cell senescence and mitochondrial dysfunction caused by Fra-1 in HeLa cells. Silencing of STAT1 also recovered metabolic reprogramming in cervical cancer cells. In summary, our results show that Fra-1 inhibited cervical cancer cell growth and the Warburg effect via STAT1-mediated regulation of the p53 signaling pathway.

The Apoptosis Mechanism of Epirubicin Combined with BCG on Human Bladder Cancer Cells.

The purpose of our study was to explore the combination effect of epirubicin and Bacillus Calmette Guerin (BCG) and its mechanism. Bladder cancer is a threat to human health worldwide. Commonly used chemotherapy drugs and biotherapy have significant therapeutic effects on bladder cancer, but the mechanism and combined effects are still unclear. To evaluate the anti-cancer effect of epirubicin combined with BCG on human bladder cancer cells, our studies were carried out. The viability of human bladder cancer cells with epirubicin and/or BCG treatments was examined by Cell Counting Kit-8 (CCK-8) assay. Apoptosis and cell cycle phase were determined by flow cytometry analysis. Pre-apoptosis factors of caspase-3, p53, B-cell lymphoma 2 associated X protein (Bax) and anti-apoptosis factor of B-cell lymphoma 2 (Bcl-2) were detected by western blot. The viability of human bladder cancer with epirubicin or BCG treatment was decreased and the viability with epirubicin combined with BCG treatment was decreased more, which were determined by CCK-8 assay. Both epirubicin and BCG increased the apoptosis rate of human bladder cancer and arrested more cells into G0/G1 phase, which were tested by flow cytometry. The expression of caspase-3, p53 and Bax was increased and the expression of Bcl-2 was decreased with epirubicin treatment on human bladder cells, which were analyzed by western blot. The expression of caspase-3 and p53 was increased with BCG treatment, which was examined by western blot. Epirubicin induced apoptosis in human bladder cancer cells by up-regulating the expression of proapoptotic factors (caspase-3, p53 and Bax) and down-regulating the expression of anti-apoptotic factor (Bcl-2). BCG promoted apoptosis of human bladder cancer cells by up-regulating the expression of caspase-3 and p53. BCG plays a potential role at the time of the combination of epirubicin and BCG on bladder cancer cells in early stage. Both epirubicin and BCG affected cell cycle distribution via arresting more bladder cancer cells at G0/G1 phase, which ultimately led bladder cancer proliferation in vitro and promoted apoptosis.

MicroRNA-221/222 Inhibits the Radiation-Induced Invasiveness and Promotes the Radiosensitivity of Malignant Meningioma Cells.

The controversy of adjuvant radiotherapy of meningiomas is at least partially due to the insufficient understanding on meningioma cells' response to irradiation and the shortage of radiosensitivity-promotion methods. MicroRNA-221 and microRNA-222 were identified as critical regulators of radiosensitivity in several other tumors. However, their effect in meningiomas has yet to be confirmed. Therefore, the malignant meningioma IOMM-Lee cells were adopted, transfected with microRNA-221/222 mimics or inhibitors, and irradiated with different dosages. The effects of radiation and microRNA-221/222 were then assessed in vitro and in vivo. Radiation dose increases and microRNA-221/222 downregulation synergistically inhibited cell proliferation and colony formation, prevented xenograft tumor progression, and promoted apoptosis, but antagonistically regulated cell invasiveness. Pairwise comparisons revealed that only high-dose radiations (6 and 8 Gy) can significantly promote cell invasiveness in comparison with unirradiated counterparts. Further comparisons exhibited that downregulating the microRNA-221/222 expression can reverse this radiation-induced cell invasiveness to a level of untransfected and unirradiated cells only if cells were irradiated with no more than 6 Gy. In addition, this approach can promote IOMM-Lee's radiosensitivity. Meanwhile, we also detected that the dose rate of irradiation affects cell cycle distribution and cell apoptosis of IOMM-Lee. A high dose rate irradiation induces G0/G1 cell cycle arrest and apoptosis-promoting effect. Therefore, for malignant meningiomas, high-dose irradiation can facilitate cell invasiveness significantly. Downregulating the microRNA-221/222 level can reverse the radiation-induced cell invasiveness while enhancing the apoptosis-promoting and proliferation-inhibiting effects of radiation and promoting cell radiosensitivity.

Characterization, modes of action, and application of a novel broad-spectrum bacteriocin BM1300 produced by Lactobacillus crustorum MN047.

Bacteriocins are ribosomally synthesized peptides with antibacterial activity against food-borne pathogenic bacteria that cause spoilage, possessing important potential for use as a natural preservative in the food industry. The novel bacteriocin BM1300 produced by Lactobacillus crustorum MN047 was identified after purification in this study. It displayed broad-spectrum antibacterial activity against some selected Gram-positive and Gram-negative bacteria. The minimum inhibitory concentration (MIC) values of BM1300 against Staphylococcus aureus ATCC 25923 and Escherichia coli ATCC 25922 were 13.4μg/mL and 6.7μg/mL, respectively. Moreover, BM1300 showed excellent thermal (between 60 and 120°C), pH (2-11), and chemical (Tween-40, Tween-80, Triton X-100, and EDTA) stabilities. Time-kill curves revealed that BM1300 exhibited bactericidal activity against S. aureus and E. coli. The scanning and transmission electron microscopy indicated that BM1300 acted by disrupting the cell membrane integrity and increasing cell membrane permeabilization of indicator bacteria. The disruption of cell membrane integrity caused by BM1300 was further demonstrated by the uptake of propidium iodide (PI) and the release of intracellular lactate dehydrogenase (LDH) and nucleic acid and proteins. Moreover, BM1300 affected cell cycle distribution to exert antibacterial activity collaboratively. Meanwhile, BM1300 inhibited the growth of S. aureus and E. coli of beef meat and improved the microbiological quality of beef meat. These findings place BM1300 as a potential biopreservative in the food industry.

The role of nucleolar spindle‐associated protein 1 in human ovarian cancer

Ovarian cancer (OC) is one of the deadliest malignancies of the female reproductive system. The present study focused on the role of Nucleolar spindle-associated protein 1 (NuSAP1) in OC. Relative expression of NuSAP1 was detected in OC tissues as well as cells. After knocking down NuSAP1 with lentivirus-mediated shRNA and verifying the knockdown efficiency via quantitative real-time polymerase chain reaction and Western blot assays, the cell proliferation, apoptosis, and cell cycle were determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide, colony formation, and flow cytometry, respectively. Transwell assay was conducted to detect the migration and invasion of OC cells. It was showed that NuSAP1 was abundantly expressed in OC tissues and cell lines. After knocking down NuSAP1 in OC cells, in addition to significantly inhibiting proliferation and colony forming ability, it also promotes apoptosis and affects cell cycle distribution. Moreover, cells in the shNuSAP1 group showed significantly suppressed migration and invasion ability compared with that in the shCtrl group. In conclusion, NuSAP1 may act as an oncogenic factor in OC and therefore might serve as an indicator for prognosis and therapeutic target for OC treatment.

LETM1 is a potential biomarker that predicts poor prognosis in gastric adenocarcinoma

Leucine zipper-EF-hand containing transmembrane protein 1 (LETM1) is closely linked to the occurrence and development of many malignant tumors. Many studies have reported that enhanced expression of LETM1 in several types of human cancers was associated with poor clinical outcomes; however, its clinical significance in gastric adenocarcinoma (GA) has not been elucidated. In this study, we assessed the expression of LETM1 along with the genes related to cancer stemness, cell cycle, and PI3K/Akt signaling in 189 paraffin-embedded GA tissue samples and GA-derived cell lines using immunohistochemistry (IHC), western blotting, and immunofluorescence. Our results showed that the expression of LETM1 was strongly correlated with the tumor grade, primary tumor (pT) stage, lymph node metastasis, clinical stage, and tumor gross type of GA. The Kaplan-Meier survival analysis revealed that patients with GA with high expression of LETM1 exhibit a shorter overall survival (OS) rate. Univariate and multivariate Cox regression analysis indicated that LETM1 is an independent poor prognostic factor of GA. Significantly, LETM1 expression was positively correlated with the expression of cancer stemness-related genes such as CD44 and LGR5 and expression of cell-cycle related gene, cyclin D1. Further, the expression of proteins involved in PI3K/Akt signaling pathway, such as pPI3K-p85 and pAkt-Thr308, was also increased. Additionally, small interfering RNA (esiRNA)-mediated silencing of LETM1 expression in GA-derived cell lines MKN28 and MKN74 strongly inhibited the expression of stemness and cell cycle-related proteins, suppressed cancer cell spheroid formation, migration and invasion ability, and affected cell cycle distribution. Furthermore, the GA-derived cell line AGS exhibited enhanced expression of LETM1, CD44, LGR5, and HIF1-α under hypoxic conditions. Lastly, we blocked PI3K expression using an inhibitor LY294002, which downregulated the expression of LETM1, pPI3K-p85, and pAkt-Thr308. Taken together, our results demonstrate that LETM1 regulates cell proliferation and promotes tumorigenicity of GA, and its overexpression is associated with the poor progression of GA. Therefore, LETM1 could serve as a potential prognostic biomarker and a therapeutic target for the better clinical management of GA.

Biochemical Inhibition of DOG1/TMEM16A Achieves Antitumoral Effects in Human Gastrointestinal Stromal Tumor Cells In Vitro.

DOG1 is a calcium-activated chloride channel that has gained attention as a promising drug target due to its involvement in several processes essential for tumor development and progression. DOG1 is overexpressed in >95% of gastrointestinal stromal tumors (GIST). The aim was to determine DOG1 inhibition antitumoral effects on GIST. Human GIST (GIST-T1 and GIST882) cell lines were used to study the effect of DOG1 inhibitors on chloride currents, viability, colony formation, and cell cycle. CaCCinh-A01 decreased chloride currents. CaCCinh-A01 and T16inh-A01 reduced GIST cell viability and CaCCinh-A01 affected cell cycle distribution leading to G1 cell-cycle arrest. CaCCinh-A01 also increased the sub-G1 phase population, indicative of apoptosis, in GIST882. CaCCinh-A01 strongly reduced the colony forming ability of the cells, whereas T16inh-A01 did not. DOG1 inhibition has antitumoral effects in GIST cells in vitro, and could potentially serve as a target for GIST therapy.

The Association of HOTAIR with the Diagnosis and Prognosis of Gastric Cancer and Its Effect on the Proliferation of Gastric Cancer Cells.

Background Long noncoding RNAs (lncRNAs) are a group of noncoding RNA with the length of more than 200nt. They have been identified as important diagnostic and prognostic molecules for many cancers and play an important role in the development of cancers. However, their clinical value and roles in gastric cancer (GC) remain unclear. Methods The expression levels of HOTAIR in 54 GC tissues and their matched adjacent nontumor tissues from GC patients and 24 normal mucosa or those with minimal gastritis as healthy controls were determined by qRT-PCR. The expression levels of HOTAIR in human GC cell lines and a normal gastric epithelium cell line were also assessed by qRT-PCR. The potential relationships between its level in GC tissues and the clinicopathological features were analyzed. Furthermore, a receiver operating characteristic (ROC) curve was constructed. Additionally, the correlation between this lncRNA and overall survival (OS) was analyzed. SiRNA transfection was used to silence the expression of HOTAIR in GC cells. And cell proliferation and cell cycle assays were employed to determine the effect of HOTAIR on GC cell growth. Western blot was performed for the detection of the P53, P21, and Bcl2 proteins. Results The expression levels of HOTAIR were significantly upregulated in GC tissues and cell lines. Increased HOTAIR was associated with tumor differentiation, lymph node and distant metastasis, and clinical stage. Furthermore, the area under the ROC curve (AUC) was up to 0.8416 (95 % CI=0.7661 to 0.9170, P<0.0001). The sensitivity and specificity were 66.67 and 87.04%, respectively. The correlation between HOTAIR expression and overall survival (OS) was statistically significant. The hazard ratio was 2.681, and 95% CI of ratio was 1.370 to 5.248. In addition, knockdown of HOTAIR can inhibit GC cell growth and affect cell cycle distribution. And knockdown of HOTAIR could enhance the protein levels of P21 and P53. Conclusion The present study demonstrated that HOTAIR was highly expressed in GC tissues and may serve as a potential diagnostic and prognostic biomarker for GC. And HOTAIR promoted GC cell proliferation.

Crotoxin from Crotalus durissus terrificus venom: In vitro cytotoxic activity of a heterodimeric phospholipase A2 on human cancer-derived cell lines

Crotoxin (CTX), a heterodimeric phospholipase present in venom of snakes of the genus Crotalus, has demonstrated a broad spectrum of pharmacological properties, such as antimicrobial, hemostatic, and antitumoral. However, the precise mechanism of its cytotoxicity and antitumoral properties remains to be determined. Therefore, in the present study, we isolated crotoxin (F1 CTX) through two steps DEAE-Sepharose and Heparin-Sepharose FF chromatography. The C-terminal sequence of the A- and B-chain protein fragment was determined by LC-MS/MS mass spectrometry, which showed 100% identity to crotoxin structure. In order to investigate its cytotoxic effects, we demonstrated that the F1 CTX fraction at 0–30 μg/mL concentrations for 72 h presented a heterogeneous response profile on nine human cancer-derived cell lines from four tumor types (pancreatic, esophagus, cervical cancer, and glioma). The glioma (GAMG and HCB151) and pancreatic (PSN-1 and PANC-1) cancer cells showed a higher sensitivity with IC50 of <0.5, 4.1, 0.7 and < 0.5 μg/mL, respectively. Conversely, F1 CTX does not reduce the viability of normal cells. On the other hand, cervical (SiHa) and esophagus (KYSE270) cancer cell lines presented higher resistance, with IC50 higher than 30.2 and 8.7 μg/mL, respectively. Moreover, F1 CTX did not affect cell cycle distribution under the conditions evaluated and seems to be more cytotoxic than cytostatic. The pro-apoptotic effect of F1 CTX treatment was demonstrated in glioma (HCB151) cell line. In addition, crotoxin revealed a potential to initiate cell responses such as DNA damage in glioma (HCB151) and pancreatic cancer by H2AX activity induction. Conversely, F1 CTX does not reduce the viability of normal cells. Importantly, the comparison of F1 CTX effect with standard chemotherapeutic agents demonstrated a greater cytotoxic potential in the majority of tumor types (glioma, pancreatic, and cervical cancer). On the other hand, F1 CTX was less cytotoxic in esophageal cell lines compared to the gemcitabine agent used in clinical practice. Therefore, this work showed that F1 CTX has a cytotoxic activity and pro-apoptotic potential, contributing to the knowledge about the F1 crotoxin properties as well as its possible use in cancer research, particularly in glioma and pancreatic cancer cell lines.