Lycorine (Lycoris radiata)-a unique natural medicine on breast cancer.

Breast cancer (BC) is one of the most common types of cancer among women worldwide. Lycorine (Lycoris radiata), a small molecule derived from the traditional Chinese herb Amaryllidaceae plants, has appeared potential effect on inhibiting the growth of cancer cells and inducing apoptosis in various types of cancer with minor side effects. To discuss the therapeutic effects and molecular mechanisms of lycorine on BC established by lycorine-treated S180 tumour-bearing mice in vivo. Furthermore, both the mitotic and microtubule assembly dynamics genes were performed by qPCR assays, and the protein expression associated with mitotic arrest was investigated by western blot. Lycorine was demonstrated to reduce sarcoma growth of S180 tumour-bearing mice and inhibit the proliferation of MCF-7 cells in concentration-dependent manner. Moreover, lycorine induced M phase cell cycle arrest via interfering with the mitotic apparatus regulated the expression of 20 genes and 15 proteins in cell cycle progression. Furthermore, this study confirmed that the potential effect of lycorine on BC might be mediated by cell cycle arrest in M phase for the first time. These results would be the consequence of exploitation of lycorine as a potential drug for BC therapy, however further preclinical and clinical studies are still needed.

A novel L-shaped ortho-quinone analog suppresses glioblastoma progression by targeting acceleration of AR degradation and regulating PI3K/AKT pathway.

Glioblastoma (GBM) is a primary intracranial malignant tumor with the highest mortality and morbidity among all malignant central nervous system tumors. Tanshinone IIA is a fat-soluble active ingredient obtained from Salvia miltiorrhiza, which has an inhibitory effect against various cancers. We designed and synthesized a novel L-shaped ortho-quinone analog TE5 with tanshinone IIA as the lead compound and tested its antitumor activity against GBM. The results indicated that TE5 effectively inhibited the proliferation, migration, and invasion of GBM cells, and demonstrated low toxicity in vitro. We found that TE5 may bind to androgen receptors and promote their degradation through the proteasome. Inhibition of the PI3K/AKT signaling pathway was also observed in TE5 treated GBM cells. Additionally, TE5 arrested the cell cycle at the G2/M phase and induced mitochondria-dependent apoptosis. In vivo experiments further confirmed the anti-tumor activity, safety, and effect on androgen receptor level of TE5 in animal models of GBM. Our results suggest that TE5 may be a potential therapeutic drug to treat GBM.

miR­576­3p/M­phase phosphoprotein 8 axis regulates the malignant progression of hepatocellular carcinoma cells via the PI3K/Akt signaling pathway.

Hepatocellular carcinoma (HCC) is a fatal digestive system cancer with unclear pathogenesis. M-phase phosphoprotein 8 (MPP8) has been shown to play a vital role in several cancer types, such as non-small cell lung cancer, gastric cancer and melanoma; however, there have been no studies into its role in HCC. The present study aimed to evaluate the role of MPP8 in regulating malignant phenotypes of liver cancer cells, and to further investigate the underlying mechanism. Bioinformatics analysis was performed to analyze related data from a public database, and to predict the potential microRNAs (miRNAs) that might target MPP8 mRNA; reverse transcription-quantitative PCR was used to measure the levels of mRNA and miRNA; western blotting was employed to detect protein levels; Cell Counting Kit-8 (CCK-8) and plate colony formation assays, wound healing assay and Transwell invasion assay were performed to evaluate the ability of cell proliferation, migration and invasion, respectively; dual-luciferase reporter gene assay was performed to identify the target association. The results showed that MPP8 was a risk factor for the survival of patients with HCC, and was up-regulated in HCC tissue samples and cell lines; MPP8 knockdown inhibited the proliferation, migration and invasion of liver cancer cells; MPP8 knockdown suppressed the PI3K/Akt pathway, and activation of this pathway reversed the inhibited liver cancer cell phenotypes by down-regulating MPP8; miR-576-3p, which was low in liver cancer cells, negatively regulated MPP8 expression by directly targeting its mRNA; up-regulating MPP8 expression reversed the inhibited signaling pathway and malignant phenotypes of liver cancer cells by miR-576-3p overexpression. In conclusion, the miR-576-3p/MPP8 axis regulates the proliferation, migration, and invasion of liver cancer cells through the PI3K/Akt signaling pathway. These findings lead novel insights into HCC progression, and propose MPP8 as a potential therapeutic target for HCC.

PLK1 inhibition leads to mitotic arrest and triggers apoptosis in cholangiocarcinoma cells.

Cholangiocarcinoma (CCA) is a lethal cancer originating from the epithelial cells within the bile duct and ranks as the second most prevalent form of liver cancer in Thailand. Polo-like kinase 1 (PLK1), a protein serine/threonine kinase, regulates a number of steps in cell mitosis and is upregulated in several types of cancer, including CCA. Our previous study identified PLK1 as a biomarker of the C1 subtype, correlating with poor prognosis in intrahepatic CCA. The present study aimed to examine the effect of PLK1 inhibition on CCA cells. Different CCA cell lines developed from Thai patients, HuCCA1, KKU055, KKU100 and KKU213A, were treated with two PLK1 inhibitors, BI2536 and BI6727, and were transfected with small interfering RNA, followed by analysis of cell proliferation, cell cycle distribution and cell apoptosis. It was discovered that BI2536 and BI6727 inhibited cell proliferation and caused G2/M-phase arrest in CCA cells. Furthermore, the number of total apoptotic cells was increased in PLK1 inhibitor-treated CCA cells. The expression levels of mitotic proteins, aurora kinase A, phosphorylated PLK1 (T210) and cyclin B1, were augmented in PLK1-inhibited CCA cells. Additionally, inhibition of PLK1 led to increased DNA damage, as determined by the upregulated levels of γH2AX and increased cleavage of poly (ADP-ribose) polymerase, an apoptotic marker. These results suggested that inhibiting PLK1 prolonged mitotic arrest and subsequently triggered cell apoptosis. Validation of the antiproliferative effects of PLK1 inhibition was accomplished through silencing of the PLK1 gene. In conclusion, targeting PLK1 provided promising results for further study as a potential candidate for targeted therapy in CCA.

DNA repair is efficient in irradiated M phase zygotes.

In somatic cells, DNA repair is attenuated during mitosis to prevent the formation of anaphase bridges and facilitate the proper segregation of sister chromatids. Irradiation-induced γH2AX foci persist for hours in M phase somatic cells. However, we observed that anaphase bridges formed in a significant fraction of mouse zygotes irradiated during mitosis. Additionally, γH2AX signals in M phase zygotes peaked 30 min after irradiation and subsequently reduced with a half-life within 1-2 h. These results suggest that the DNA repair system may operate efficiently in M phase zygotes following irradiation, leading to the frequent formation of anaphase bridges. The absence of H2AX promoted the successful segregation of sister chromatids and enhanced the development of embryos to the blastocyst stage. The DNA repair system may be differentially regulated during the M phase of the first cell cycle to ensure the immediate elimination of damaged zygotes, thereby efficiently preventing transmission of mutations to subsequent generations.

Lasiokaurin Regulates PLK1 to Induce Breast Cancer Cell G2/M Phase Block and Apoptosis.

Aim of the study: To investigate the anti-tumor effects of Lasiokaurin on breast cancer and explore its underlying molecular mechanism. Materials and methods: In this study, MTT assay, plate colony formation assays, soft agar assay, and EdU assay were employed to evaluate the anti-proliferation effects of LAS. Apoptosis and cell cycle distribution were detected by flow cytometry. The molecular mechanism was predicted by performing RNA sequencing and verified by using immunoblotting assays. Breast cancer organiods derived from patient-derived xenografts model and MDA-MB-231 xenograft mouse model were established to assess the effect of LAS. Results: Our study showed that LAS treatment significantly suppressed cell viability of 5 breast cancer cell lines, with the IC50 value of approximately 1-5 µM. LAS also inhibitied the clonogenic ability and DNA synthesis of breast cancer cells, Moreover, LAS induced apoptosis and G2/M cell cycle arrest in SK-BR-3 and MDA-MB-231 cells. Notably, transcriptomic analysis predicted the mechanistic involvement of PLK1 in LAS-suppressed breast cancer progression. Our experiment data further verified that LAS reduced PLK1 mRNA and protein expression in breast cancer, accompanied by downregulating CDC25C and AKT phosphorylation. Ultimately, we confirmed that LAS inhibit breast cancer growth via inhibiting PLK1 pathway in vivo. Conclusions: Collectively, our findings revealed that LAS inhibits breast cancer progression via regulating PLK1 pathway, which provids scientific evidence for the use of traditional Chinese medicine in cancer therapy.

Telocinobufagin, a PLK1 suppressor that inhibits tumor growth and metastasis by modulating CDC25c and CTCF in HNSCC cells.

BACKGROUND: The high metastasis and mortality rates of head and neck squamous cell carcinoma (HNSCC) urgently require new treatment targets and drugs. A steroidal component of ChanSu, telocinobufagin (TBG), was verified to have anti-cancer effects in various tumors, but its activity and mechanism in anti-HNSCC were still unknown. PURPOSE: This study tried to demonstrate the anti-tumor effect of TBG on HNSCC and verify its potential mechanism. METHODS: The effect of TBG on cell proliferation and metastasis were performed and the TBG changed genes were detected by RNA-seq analysis in HNSCC cells. The GSEA and PPI analysis were used to identify the pathways targeted for TBG-regulated genes. Meanwhile, the mechanism of TBG on anti-proliferative and anti-metastasis were investigated in vitro and in vivo. RESULTS: The in vitro and in vivo experiments confirmed that TBG has favorable anti-tumor effects by induced G2/M phase arrest and suppressed metastasis in HNSCC cells. Further RNA-seq analysis demonstrated the genes regulated by TBG were enriched at the G2/M checkpoint and PLK1 signaling pathway. Then, the bioinformatic analysis of clinical data found that high expressed PLK1 were closely associated with poor overall survival in HNSCC patients. Furthermore, PLK1 directly and indirectly modulated G2/M phase and metastasis (by regulated CTCF) in HNSCC cells, simultaneously. TBG significantly inhibited the protein levels of PLK1 in both phosphorylated and non-phosphorylated forms and then, in one way, inactivated PLK1 failed to activate G2/M phase-related proteins (including CDK1, CDC25c, and cyclin B1). In another way, be inhibited PLK1 unable promote the nuclear translocation of CTCF and thus suppressed HNSC cell metastasis. In contrast, the anti-proliferative and anti-metastasis effects of TBG on HNSCC cell were vanished when cells high-expressed PLK1. CONCLUSION: The present study verified that PLK1 mediated TBG induced anti-tumor effect by modulated G2/M phase and metastasis in HNSCC cells.

Survivin Mediates Mitotic Onset in HeLa Cells Through Activation of the Cdk1-Cdc25B Axis.

The Survivin protein has roles in repairing incorrect microtubule-kinetochore attachments at prometaphase, and the faithful execution of cytokinesis, both as part of the chromosomal passenger complex (CPC) (1). In this context, errors frequently lead to aneuploidy, polyploidy and cancer (1). Adding to these well-known roles of this protein, this paper now shows for the first time that Survivin is required for cancer cells to enter mitosis, and that, in its absence, HeLa cells accumulate at early prophase, or prior to reported before (2, 3). This early prophase blockage is demonstrated by the presence of an intact nuclear lamina and low Cdk1 activity (4). Importantly, escaping the arrest induced by Survivin abrogation leads to multiple mitotic defects, or mitotic catastrophe, and eventually cell death. Mechanistically, Cdk1 does not localize at the centrosome in the absence of Survivin pointing at an impairment in signaling through the Cdc25B-Cdk1 axis. In agreement, even though Survivin directly interacts with Cdc25B, both in vitro and in vivo, in its absence, an inactive cytosolic Cdc25B-Cdk1-Cyclin B1 complex accumulates. This flaw in Cdc25B activation can however be reversed in Survivin-depleted HeLa cell extracts to which the recombinant Survivin protein is added back. Finally, a role for Survivin in the Cdc25B-mediated activation of Cdk1 is confirmed by overriding the early prophase blockage induced in cells lacking Survivin through the expression of a gain-of-function Cdc25B mutant.

BubR1 and cyclin B1 immunoexpression in pleomorphic adenoma and polymorphous adenocarcinoma of minor salivary glands.

The immunoexpression of BubR1 and cyclin B1 in pleomorphic adenoma (PA) and polymorphic adenocarcinoma (PAC) in minor salivary glands is poorly studied. Thus, a retrospective and observational study was performed to provide a better understanding of the role and immunopositivity patterns of these proteins in these lesions. Sixteen cases of PA and 16 cases of PAC were selected. Parenchyma cells were submitted to quantitative immunohistochemical analysis through the labeling index. Cytoplasmic immunoexpression of BubR1 was observed in neoplastic cells from all analyzed PA and PAC cases. All PA cases and 93.7% of PAC exhibited nuclear immunoexpression of BubR1. Higher cytoplasmic and nuclear immunoexpression of BubR1 was observed in PAC (p = 0.001 and p = 0.122, respectively). Cytoplasmic immunoexpression of cyclin B1 was observed in all cases of PA and PAC, with a higher labeling index in the latter (p < 0.001). There was a significant positive correlation between nuclear and cytoplasmic BubR1 immunoexpressions (p < 0.001) in PA and a significant negative correlation between BubR1 and cyclin B1 cytoplasmic immunoexpressions (p = 0.014) in PAC. The higher cytoplasmic and nuclear immunoexpression of BubR1 in PACs suggests the continuous maintenance of neoplastic cells in the cell cycle and migration. Higher immunoexpression of cyclin B1 supports this lesion's enhanced proliferative and migration ability.

2H-2M Phase Control of WSe2 Nanosheets by Se Enrichment Toward Enhanced Electrocatalytic Hydrogen Evolution Reaction.

The phase control of transition metal dichalcogenides (TMDs) is an intriguing approach for tuning the electronic structure toward extensive applications. In this study, WSe2 nanosheets synthesized via a colloidal reaction exhibit a phase conversion from semiconducting 2H to metallic 2M under Se-rich growth conditions (i.e., increasing the concentration of Se precursor or lowering the growth temperature). High-resolution scanning transmission electron microscopy images are used to identify the stacking sequence of the 2M phase, which is distinctive from that of the 1T' phase. First-principles calculations employing various Se-rich models (intercalation and substitution) indicated that Se enrichment induces conversion to the 2M phase. The 2M phase WSe2 nanosheets with the Se excess exhibited enhanced electrocatalytic performance in the hydrogen evolution reaction (HER). In situ X-ray absorption fine structure studies suggested that the excess Se atoms in the 2M phase WSe2 enhanced the HER catalytic activity, which is supported by the Gibbs free energy (ΔGH* ) of H adsorption and the Fermi abundance function. These results provide an appealing strategy for phase control of TMD catalysts.

A network pharmacology- and transcriptomics-based investigation reveals an inhibitory role of ß-sitosterol in glioma via the EGFR/MAPK signaling pathway.

Glioma is characterized by rapid cell proliferation, aggressive invasion, altered apoptosis and a poor prognosis. ß-Sitosterol, a kind of phytosterol, has been shown to possess anticancer activities. Our current study aims to investigate the effects of ß-sitosterol on gliomas and reveal the underlying mechanisms. Our results show that ß-sitosterol effectively inhibits the growth of U87 cells by inhibiting proliferation and inducing G2/M phase arrest and apoptosis. In addition, ß-sitosterol inhibits migration by downregulating markers of epithelial-mesenchymal transition (EMT). Mechanistically, network pharmacology and transcriptomics approaches illustrate that the EGFR/MAPK signaling pathway may be responsible for the inhibitory effect of ß-sitosterol on glioma. Afterward, the results show that ß-sitosterol effectively suppresses the EGFR/MAPK signaling pathway. Moreover, ß-sitosterol significantly inhibits tumor growth in a U87 xenograft nude mouse model. ß-Sitosterol inhibits U87 cell proliferation and migration and induces apoptosis and cell cycle arrest in U87 cells by blocking the EGFR/MAPK signaling pathway. These results suggest that ß-sitosterol may be a promising therapeutic agent for the treatment of glioma.

(S)-3-(3-Fluoro-4-Methoxybenzyl)-5,6,7-Trimethoxychroman-4-One Suppresses the Proliferation of Huh7 Cells by Up-regulating P21 and Inducing G2/M Phase Arrest.

BACKGROUND/AIM: Hepatocellular carcinoma (HCC) is a prevalent type of cancer worldwide. Although sorafenib is the only chemotherapy agent used for HCC, there is a need to discover a more potent anticancer agent with reduced side-effects. The compound, (S)-3-(3-fluoro-4-methoxybenzyl)-5,6,7-trimethoxychroman-4-one (FMTC), was designed to inhibit tubulin assembly but its specific mechanisms of action have not been previously investigated. Herein, we investigated the regulation mechanisms by which FMTC affects the proliferation of the HCC cell line, Huh7. MATERIALS AND METHODS: The effects of FMTC on cell viability and growth were analyzed in the HCC cell line, Huh7. Cell cycle and apoptosis regulated by FMTC were analyzed using flow cytometry. To verify the regulation of mRNA and protein expression of cell proliferation-related factors by FMTC in Huh7 cells, RT-qPCR and western blot analyses were employed. RESULTS: FMTC suppressed cell division dose-dependently by triggering cell cycle arrest at the G2/M phase via p21 up-regulation. The increased phosphorylation of histone H3 on Ser-10 and the condensation of chromatin in FMTC-treated cells indicated mitotic arrest. Prolonged FMTC-induced cell cycle arrest triggered apoptosis. CONCLUSION: FMTC inhibits the proliferation of human liver cancer cells by up-regulating p21, thereby inducing cell cycle arrest at the G2/M phase. These findings highlight FMTC as a novel agent for HCC treatment.

Aurora A kinase inhibition induces accumulation of SCLC tumor cells in mitosis with restored interferon signaling to increase response to PD-L1.

Despite small cell lung cancers (SCLCs) having a high mutational burden, programmed death-ligand 1 (PD-L1) immunotherapy only modestly increases survival. A subset of SCLCs that lose their ASCL1 neuroendocrine phenotype and restore innate immune signaling (termed the "inflammatory" subtype) have durable responses to PD-L1. Some SCLCs are highly sensitive to Aurora kinase inhibitors, but early-phase trials show short-lived responses, suggesting effective therapeutic combinations are needed to increase their durability. Using immunocompetent SCLC genetically engineered mouse models (GEMMs) and syngeneic xenografts, we show durable efficacy with the combination of a highly specific Aurora A kinase inhibitor (LSN3321213) and PD-L1. LSN3321213 causes accumulation of tumor cells in mitosis with lower ASCL1 expression and higher expression of interferon target genes and antigen-presentation genes mimicking the inflammatory subtype in a cell-cycle-dependent manner. These data demonstrate that inflammatory gene expression is restored in mitosis in SCLC, which can be exploited by Aurora A kinase inhibition.

Oscillations in PP1 activity are essential for accurate progression through mammalian oocyte meiosis.

Tightly controlled fluctuations in kinase and phosphatase activity play important roles in regulating M-phase transitions. Protein Phosphatase 1 (PP1) is one of these phosphatases, with oscillations in PP1 activity driving mitotic M-phase. Evidence from a variety of experimental systems also points to roles in meiosis. Here, we report that PP1 is important for M-phase transitions through mouse oocyte meiosis. We employed a unique small-molecule approach to inhibit or activate PP1 at distinct phases of mouse oocyte meiosis. These studies show that temporal control of PP1 activity is essential for the G2/M transition, metaphase I/anaphase I transition, and the formation of a normal metaphase II oocyte. Our data also reveal that inappropriate activation of PP1 is more deleterious at the G2/M transition than at prometaphase I-to-metaphase I, and that an active pool of PP1 during prometaphase is vital for metaphase I/anaphase I transition and metaphase II chromosome alignment. Taken together, these results establish that loss of oscillations in PP1 activity causes a range of severe meiotic defects, pointing to essential roles for PP1 in female fertility, and more broadly, M-phase regulation.

BRD4770 inhibits vascular smooth muscle cell proliferation via SUV39H2, but not EHMT2 to protect against neointima formation.

The behavior of vascular smooth muscle cells (VSMCs) contributes to the formation of neointima. We previously found that EHMT2 suppressed autophagy activation in VSMCs. BRD4770, an inhibitor of EHMT2/G9a, plays a critical role in several kinds of cancers. However, whether and how BRD4770 regulates the behavior of VSMCs remain unknown. In this study, we evaluate the cellular effect of BRD4770 on VSMCs by series of experiments in vivo and ex vivo. We demonstrated that BRD4770 inhibited VSMCs' growth by blockage in G2/M phase in VSMCs. Moreover, our results demonstrated that the inhibition of proliferation was independent on autophagy or EHMT2 suppression which we previous reported. Mechanistically, BRD4770 exhibited an off-target effect from EHMT2 and our further study reveal that the proliferation inhibitory effect by BRD4770 was associated with suppressing on SUV39H2/KTM1B. In vivo, BRD4770 was also verified to rescue VIH. Thus, BRD4770 function as a crucial negative regulator of VSMC proliferation via SUV39H2 and G2/M cell cycle arrest and BRD4770 could be a molecule for the therapy of vascular restenosis.

Hdac1-deficiency affects the cell cycle axis Cdc25-Cdk1 causing impaired G2/M phase progression and reduced cardiomyocyte proliferation in zebrafish.

Zebrafish have the ability to fully regenerate their hearts after injury since cardiomyocytes subsequently dedifferentiate, re-enter cell cycle, and proliferate to replace damaged myocardial tissue. Recent research identified the reactivation of dormant developmental pathways during cardiac regeneration in adult zebrafish, suggesting pro-proliferative pathways important for developmental heart growth to be also critical for regenerative heart growth after injury. Histone deacetylase 1 (Hdac1) was recently shown to control both, embryonic as well as adult regenerative cardiomyocyte proliferation in the zebrafish model. Nevertheless, regulatory pathways controlled by Hdac1 are not defined yet. By analyzing RNA-seq-derived transcriptional profiles of the Hdac1-deficient zebrafish mutant baldrian, we here identified DNA damage response (DDR) pathways activated in baldrian mutant embryos. Surprisingly, although the DDR signaling pathway was transcriptionally activated, we found the complete loss of protein expression of the known DDR effector and cell cycle inhibitor p21. Consequently, we observed an upregulation of the p21-downstream target Cdk2, implying elevated G1/S phase transition in Hdac1-deficient zebrafish hearts. Remarkably, Cdk1, another p21-but also Cdc25-downstream target was downregulated. Here, we found the significant downregulation of Cdc25 protein expression, explaining reduced Cdk1 levels and suggesting impaired G2/M phase progression in Hdac1-deficient zebrafish embryos. To finally prove defective cell cycle progression due to Hdac1 loss, we conducted Cytometer-based cell cycle analyses in HDAC1-deficient murine HL-1 cardiomyocytes and indeed found impaired G2/M phase transition resulting in defective cardiomyocyte proliferation. In conclusion, our results suggest a critical role of Hdac1 in maintaining both, regular G1/S and G2/M phase transition in cardiomyocytes by controlling the expression of essential cell cycle regulators such as p21 and Cdc25.

Illuminating DEPDC1B in Multi-pronged Regulation of Tumor Progression.

DEPDC1B (aliases BRCC3, XTP8, XTP1) is a DEP (Dishevelled, Egl-1, Pleckstrin) and Rho-GAP-like domains containing predominately membrane-associated protein. Earlier, we and others have reported that DEPDC1B is a downstream effector of Raf-1 and long noncoding RNA lncNB1, and an upstream positive effector of pERK. Consistently, DEPDC1B knockdown is associated with downregulation of ligand-stimulated pERK expression. We demonstrate here that DEPDC1B N-terminus binds to the p85 subunit of PI3K, and DEPDC1B overexpression results in decreased ligand-stimulated tyrosine phosphorylation of p85 and downregulation of pAKT1. Collectively, we propose that DEPDC1B is a novel cross-regulator of AKT1 and ERK, two of the prominent pathways of tumor progression. Our data showing high levels of DEPDC1B mRNA and protein during the G2/M phase have significant implications in cell entry into mitosis. Indeed, DEPDC1B accumulation during the G2/M phase has been associated with disassembly of focal adhesions and cell de-adhesion, referred to as a DEPDC1B-mediated de-adhesion mitotic checkpoint. DEPDC1B is a direct target of transcription factor SOX10, and SOX10-DEPDC1B-SCUBE3 axis has been associated with angiogenesis and metastasis. The Scansite analysis of the DEPDC1B amino acid sequence shows binding motifs for three well-established cancer therapeutic targets CDK1, DNA-PK, and aurora kinase A/B. These interactions and functionalities, if validated, may further implicate DEPDC1B in regulation of DNA damage-repair and cell cycle progression processes. Finally, a survey of the publicly available datasets indicates that high DEPDC1B expression is a viable biomarker in breast, lung, pancreatic and renal cell carcinomas, and melanoma. Currently, the systems and integrative biology of DEPDC1B is far from comprehensive. Future investigations are necessary in order to understand how DEPDC1B might impact AKT, ERK, and other networks, albeit in a context-dependent manner, and influence the actionable molecular, spatial, and temporal vulnerabilities within these networks in cancer cells.

CA916798 predicts poor prognosis and promotes Gefitinib resistance for lung adenocarcinoma.

BACKGROUND: Our previous studies have identified CA916798 as a chemotherapy resistance-associated gene in lung cancer. However, the histopathological relevance and biological function of CA916798 in lung adenocarcinoma (LUAD) remains to be delineated. In this study, we further investigated and explored the clinical and biological significance of CA916798 in LUAD. METHODS: The relationship between CA916798 and clinical features of LUAD was analyzed by tissue array and online database. CCK8 and flow cytometry were used to measure cell proliferation and cell cycle of LUAD after knockdown of CA916798 gene. qRT-PCR and western blotting were used to detect the changes of cell cycle-related genes after knockdown or overexpression of CA916798. The tumorigenesis of LUAD cells was evaluated with or without engineering manipulation of CA916798 gene expression. Response to Gefitinib was evaluated using LUAD cells with forced expression or knockdown of CA916798. RESULTS: The analysis on LUAD samples showed that high expression of CA916798 was tightly correlated with pathological progression and poor prognosis of LUAD patients. A critical methylation site in promoter region of CA916798 gene was identified to be related with CA916798 gene expression. Forced expression of CA916798 relieved the inhibitory effects of WEE1 on CDK1 and facilitated cell cycle progression from G2 phase to M phase. However, knockdown of CA916798 enhanced WEE1 function and resulted in G2/M phase arrest. Consistently, chemical suppression of CDK1 dramatically inhibited G2/M phase transition in LUAD cells with high expression of CA916798. Finally, we found that CA916798 was highly expressed in Gefitinib-resistant LUAD cells. Exogenous expression of CA916798 was sufficient to endow Gefitinib resistance with tumor cells, but interference of CA916798 expression largely rescued response of tumor cells to Gefitinib. CONCLUSIONS: CA916798 played oncogenic roles and was correlated with the development of Gefitinib resistance in LUAD cells. Therefore, CA916798 could be considered as a promising prognostic marker and a therapeutic target for LUAD.

Downregulation of fatty acid oxidation led by Hilpda increases G2/M arrest/delay-induced kidney fibrosis.

Hypoxia-regulated proximal tubular epithelial cells (PTCs) G2/M phase arrest/delay was involved in production of renal tubulointerstitial fibrosis (TIF). TIF is a common pathological manifestation of progression in patients with chronic kidney disease (CKD), and is often accompanied by lipid accumulation in renal tubules. However, cause-effect relationship between hypoxia-inducible lipid droplet-associated protein (Hilpda), lipid accumulation, G2/M phase arrest/delay and TIF remains unclear. Here we found that overexpression of Hilpda downregulated adipose triglyceride lipase (ATGL) promoted triglyceride overload in the form of lipid accumulation, leading to defective fatty acid ß-oxidation (FAO), ATP depletion in a human PTC cell line (HK-2) under hypoxia and in mice kidney tissue treated with unilateral ureteral obstruction (UUO) and unilateral ischemia-reperfusion injury (UIRI). Hilpda-induced lipid accumulation caused mitochondrial dysfunction, enhanced expression of profibrogenic factors TGF-ß1, α-SMA and Collagen I elevation, and reduced expression of G2/M phase-associated gene CDK1, as well as increased CyclinB1/D1 ratio, resulted in G2/M phase arrest/delay and profibrogenic phenotypes. Hilpda deficiency in HK-2 cell and kidney of mice with UUO had sustained expression of ATGL and CDK1 and reduced expression of TGF-ß1, Collagen I and CyclinB1/D1 ratio, resulting in the amelioration of lipid accumulation and G2/M arrest/delay and subsequent TIF. Expression of Hilpda correlated with lipid accumulation, was positively associated with tubulointerstitial fibrosis in tissue samples from patients with CKD. Our findings suggest that Hilpda deranges fatty acid metabolism in PTCs, which leads to G2/M phase arrest/delay and upregulation of profibrogenic factors, and consequently promote TIF which possibly underlie pathogenesis of CKD.

Pyrrolyldihydropyrazino[1,2-a]indoletrione Analogue Microtubule Inhibitor Induces Cell-Cycle Arrest and Apoptosis in Colorectal Cancer Cells.

In this study, 2-benzyl-10a-(1H-pyrrol-2-yl)-2,3-dihydropyrazino[1,2-a]indole-1,4,10(10aH)-trione (DHPITO), a previously identified inhibitor against hepatocellular carcinoma cells, is shown to exert its cytotoxic effects by suppressing the proliferation and growth of CRC cells. An investigation of its molecular mechanism confirmed that the cytotoxic activity of DHPITO is mediated through the targeting of microtubules with the promotion of subsequent microtubule polymerisation. With its microtubule-stabilising ability, DHPITO also consistently arrested the cell cycle of the CRC cells at the G2/M phase by promoting the phosphorylation of histone 3 and the accumulation of EB1 at the cell equator, reduced the levels of CRC cell migration and invasion, and induced cellular apoptosis. Furthermore, the compound could suppress both tumour size and tumour weight in a CRC xenograft model without any obvious side effects. Taken together, the findings of the present study reveal the antiproliferative and antitumour mechanisms through which DHPITO exerts its activity, indicating its potential as a putative chemotherapeutic agent and lead compound with a novel structure.