Inhibitors of anti-apoptotic Bcl-2 family proteins exhibit potent and broad-spectrum anti-mammarenavirus activity via cell cycle arrest at G0/G1 phase

Targeting host factors is a promising strategy to develop broad-spectrum antiviral drugs. Drugs targeting anti-apoptotic Bcl-2 family proteins that were originally developed as tumor suppressors have been reported to inhibit multiplication of different types of viruses. However, the mechanisms whereby Bcl-2 inhibitors exert their antiviral activity remain poorly understood. In this study, we have investigated the mechanisms by which obatoclax (OLX) and ABT-737 Bcl-2 inhibitors exhibited a potent antiviral activity against the mammarenavirus lymphocytic choriomeningitis virus (LCMV). OLX and ABT-737 potent anti-LCMV activity was not associated with their pro-apoptotic properties, but rather their ability of inducing cell arrest at G0/G1 phase. OLX and ABT-737 mediated inhibition of Bcl-2 correlated with reduced expression levels of thymidine kinase 1 (TK1), cyclin A2 (CCNA2), and cyclin B1 (CCNB1) cell cycle regulators. In addition, siRNA-mediated knock down of TK1, CCNA2, and CCNB1 resulted in reduced levels of LCMV multiplication. The antiviral activity exerted by Bcl-2 inhibitors correlated with reduced levels of viral RNA synthesis at early times of infection. Importantly, ABT-737 exhibited moderate efficacy in a mouse model of LCMV infection, and Bcl-2 inhibitors displayed broad-spectrum antiviral activities against different mammarenaviruses and SARS-CoV-2. Our results suggest that Bcl-2 inhibitors, actively being explored as anti-cancer therapeutics, might be repositioned as broad-spectrum antivirals. IMPORTANCE Anti-apoptotic Bcl-2 inhibitors have been shown to exert potent antiviral activities against various types of viruses via mechanisms that are currently poorly understood. This study has revealed that Bcl-2 inhibitors mediated cell cycle arrest at the G0/G1 phase, rather than their pro-apoptotic activity, plays a critical role in blocking mammarenavirus multiplication in cultured cells. In addition, we show that Bcl-2 inhibitor ABT-737 exhibited moderate anti-mammarenavirus activity in vivo , and that Bcl-2 inhibitors displayed broad-spectrum antiviral activities against different mammarenaviruses and SARS-CoV-2. Our results suggest that Bcl-2 inhibitors, actively being explored as anti-cancer therapeutics, might be repositioned as broad-spectrum antivirals.

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Adenomatous Polyposis Coli Loss Controls Cell Cycle Regulators and Response to Paclitaxel

10.1101/2020.10.31.362608 ◽

2020 ◽

Cited By ~ 1

Author(s):

Emily M. Astarita ◽

Camden A. Hoover ◽

Sara M. Maloney ◽

T. Murlidharan Nair ◽

Jenifer R. Prosperi

Keyword(s):

Breast Cancer ◽

Cell Cycle ◽

Adenomatous Polyposis Coli ◽

Cyclin B1 ◽

Cell Cycle Analysis ◽

Specific Cell ◽

Breast Cancers ◽

Cell Cycle Regulators ◽

Adenomatous Polyposis ◽

Polyposis Coli

AbstractAdenomatous Polyposis Coli (APC) is lost in approximately 70% of sporadic breast cancers, with an inclination towards triple negative breast cancer (TNBC). TNBC is treated with traditional chemotherapy, such as paclitaxel (PTX); however, tumors often develop drug resistance. We previously created APC knockdown cells (APC shRNA1) using the human TNBC cells, MDA-MB-157, and showed that APC loss induces PTX resistance. To understand the mechanisms behind APC-mediated PTX response, we performed cell cycle analysis and analyzed cell cycle related proteins. Cell cycle analysis indicated increased G2/M population in PTX-treated APC shRNA1 cells compared to PTX-treated controls, suggesting that APC expression does not alter PTX-induced G2/M arrest. We further studied the subcellular localization of the G2/M transition proteins, cyclin B1 and CDK1. The APC shRNA1 cells had increased CDK1, which was preferentially localized to the cytoplasm, and increased CDK6. RNA-sequencing was performed to gain a global understanding of changes downstream of APC loss and identified a broad mis-regulation of cell cycle-related genes in APC shRNA1 cells. Our studies are the first to show an interaction between APC and taxane response in breast cancer. The implications include designing combination therapy to re-sensitize APC-mutant breast cancers to taxanes using the specific cell cycle alterations.

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C/EBPϵ interacts with retinoblastoma and E2F1 during granulopoiesis

Blood ◽

10.1182/blood-2003-01-0159 ◽

2004 ◽

Vol 103 (3) ◽

pp. 828-835 ◽

Cited By ~ 45

Author(s):

Sigal Gery ◽

Adrian F. Gombart ◽

Yuen K. Fung ◽

H. Phillip Koeffler

Keyword(s):

Cell Cycle ◽

Transcription Factor ◽

Broad Spectrum ◽

Transcriptional Activity ◽

Myeloid Cells ◽

Cell Cycle Regulators ◽

Granulocytic Differentiation ◽

Specific Transcription Factor ◽

Enhancer Binding Protein ◽

Reporter Assays

AbstractCCAAT enhancer binding protein epsilon (C/EBPϵ) is a myeloid specific transcription factor that is essential for terminal granulocytic differentiation. Retinoblastoma (Rb) and E2F1 are critical cell cycle regulators that also have been implicated in several differentiation systems. Here, we demonstrate that C/EBPϵ interacts with Rb and E2F1 during granulocytic differentiation in NB4 and U937 human myeloid cells and in 32Dcl3 murine myeloid precursor cells. The interaction between C/EBPϵ and Rb enhances C/EBPϵ-mediated transcription of myeloid specific genes both in reporter assays and endogenously. The C/EBPϵ-E2F1 interaction results in repression of E2F1-mediated transcriptional activity. Finally, overexpression of C/EBPϵ in human myeloid cells leads to down-regulation of c-Myc. We propose that the interactions between C/EBPϵ, a tissue-specific transcription factor, and the broad-spectrum proteins, Rb and E2F1, are important in C/EBPϵ-induced terminal granulocytic differentiation.

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Anti-proliferative effect of estrogen in breast cancer cells that re-express ERα is mediated by aberrant regulation of cell cycle genes

Journal of Molecular Endocrinology ◽

10.1677/jme.1.01677 ◽

2005 ◽

Vol 34 (2) ◽

pp. 535-551 ◽

Cited By ~ 56

Author(s):

J G Moggs ◽

T C Murphy ◽

F L Lim ◽

D J Moore ◽

R Stuckey ◽

...

Keyword(s):

Breast Cancer ◽

Cell Cycle ◽

Cancer Cells ◽

Breast Cancer Cells ◽

Cyclin B1 ◽

Tumour Suppressor Genes ◽

Cell Cycle Regulators ◽

Adenoviral Infection ◽

Promote Cell Proliferation ◽

Er Positive

Estrogen receptor (ER)-negative breast carcinomas do not respond to hormone therapy, making their effective treatment very difficult. The re-expression of ERα in ER-negative MDA-MB-231 breast cancer cells has been used as a model system, in which hormone-dependent responses can be restored. Paradoxically, in contrast to the mitogenic activity of 17β-estradiol (E2) in ER-positive breast cancer cells, E2 suppresses proliferation in ER-negative breast cancer cells in which ERα has been re-expressed. We have used global gene expression profiling to investigate the mechanism by which E2 suppresses proliferation in MDA-MB-231 cells that express ERα through adenoviral infection. We show that a number of genes known to promote cell proliferation and survival are repressed by E2 in these cells. These include genes encoding the anti-apoptosis factor SURVIVIN, positive cell cycle regulators (CDC2, CYCLIN B1, CYCLIN B2, CYCLIN G1, CHK1, BUB3, STK6, SKB1, CSE1 L) and chromosome replication proteins (MCM2, MCM3, FEN1, RRM2, TOP2A, RFC1). In parallel, E2-induced the expression of the negative cell cycle regulators KIP2 and QUIESCIN Q6, and the tumour-suppressor genes E-CADHERIN and NBL1. Strikingly, the expression of several of these genes is regulated in the opposite direction by E2 compared with their regulation in ER-positive MCF-7 cells. Together, these data suggest a mechanism for the E2-dependent suppression of proliferation in ER-negative breast cancer cells into which ERα has been reintroduced.

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CCNE1 and E2F1 Partially Suppress G1 Phase Arrest Caused by Spliceostatin A Treatment

International Journal of Molecular Sciences ◽

10.3390/ijms222111623 ◽

2021 ◽

Vol 22 (21) ◽

pp. 11623

Author(s):

Kei Kikuchi ◽

Daisuke Kaida

Keyword(s):

Cell Cycle ◽

Cell Cycle Progression ◽

Kinase Inhibitor ◽

G1 Phase ◽

Cell Cycle Regulators ◽

Protein Levels ◽

Cyclin Dependent Kinase Inhibitor ◽

Phase Arrest ◽

G1 Phase Arrest ◽

Spliceostatin A

The potent splicing inhibitor spliceostatin A (SSA) inhibits cell cycle progression at the G1 and G2/M phases. We previously reported that upregulation of the p27 cyclin-dependent kinase inhibitor encoded by CDKN1B and its C-terminal truncated form, namely p27*, which is translated from CDKN1B pre-mRNA, is one of the causes of G1 phase arrest caused by SSA treatment. However, the detailed molecular mechanism underlying G1 phase arrest caused by SSA treatment remains to be elucidated. In this study, we found that SSA treatment caused the downregulation of cell cycle regulators, including CCNE1, CCNE2, and E2F1, at both the mRNA and protein levels. We also found that transcription elongation of the genes was deficient in SSA-treated cells. The overexpression of CCNE1 and E2F1 in combination with CDKN1B knockout partially suppressed G1 phase arrest caused by SSA treatment. These results suggest that the downregulation of CCNE1 and E2F1 contribute to the G1 phase arrest induced by SSA treatment, although they do not exclude the involvement of other factors in SSA-induced G1 phase arrest.

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In Vitro Inhibition of Piper nigrum and Piperine on Growth, Migration, and Invasion of PANC-1 Human Pancreatic Cancer Cells

Natural Product Communications ◽

10.1177/1934578x211057694 ◽

2021 ◽

Vol 16 (11) ◽

pp. 1934578X2110576

Author(s):

Ji Hye Jeong ◽

Jae-Ha Ryu ◽

Hwa Jin Lee

Keyword(s):

Cell Cycle ◽

Pancreatic Cancer ◽

Cancer Cells ◽

Cyclin B1 ◽

Human Pancreatic Cancer ◽

Major Constituent ◽

Piper Nigrum ◽

Migration And Invasion ◽

Cell Cycle Regulators ◽

Pancreatic Cancer Cells

Several dietary and medicinal herbs have been shown to be effective in the treatment and prevention of cancer. Although Piper nigrum has been shown to have anti-cancer activities against various cancer cells, its anti-pancreatic cancer properties have not been reported. In the present study, P. nigrum extract (PNE) inhibited proliferation of PANC-1 human pancreatic cancer cells. Flow cytometry showed G0/G1 arrest caused by PNE in PANC-1 cells. In addition, Western blot analysis showed that PNE suppressed the protein levels of cell cycle regulators such as cyclin B1, cyclin D1, survivin, and Forkhead box M1 (FoxM1). These findings suggested that the inhibitory activity of PNE against the growth of PANC-1 cells was correlated with cell cycle arrest and repression of cell cycle regulators. Wound healing and trans-well assays showed that PNE suppressed migration and invasion of PANC-1 cells. Piperine, a major alkaloid of Piper nigrum, was identified as the main component of PNE by HPLC analysis. Piperine also attenuated the cell growth, migration, and invasion of PANC-1 cells, suggesting its contribution to the anti-pancreatic cancer effects of PNE. These results demonstrate that PNE and its major constituent, piperine, have anti-pancreatic cancer properties such as growth-inhibition, anti-migration, and anti-invasion of cancer cells.

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CTLA-4 affects expression of key cell cycle regulators of G0/G1 phase in neoplastic lymphocytes from patients with chronic lymphocytic leukaemia

Clinical and Experimental Medicine ◽

10.1007/s10238-015-0360-7 ◽

2015 ◽

Vol 16 (3) ◽

pp. 317-332 ◽

Cited By ~ 4

Author(s):

Lidia Ciszak ◽

Irena Frydecka ◽

Dariusz Wolowiec ◽

Aleksandra Szteblich ◽

Agata Kosmaczewska

Keyword(s):

Cell Cycle ◽

Chronic Lymphocytic Leukaemia ◽

Lymphocytic Leukaemia ◽

G1 Phase ◽

Cell Cycle Regulators ◽

Neoplastic Lymphocytes

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Aberrant expression of G1-phase cell cycle regulators in flat and exophytic adenomas of the human colon

Gastroenterology ◽

10.1053/gast.2001.24880 ◽

2001 ◽

Vol 120 (7) ◽

pp. 1680-1688 ◽

Cited By ~ 38

Author(s):

Jirina Bartkova ◽

Minna Thullberg ◽

Premysl Slezak ◽

Edgar Jaramillo ◽

Carlos Rubio ◽

...

Keyword(s):

Cell Cycle ◽

Human Colon ◽

Phase Cell ◽

G1 Phase ◽

Cell Cycle Regulators ◽

Aberrant Expression

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Location of cell cycle regulators cyclin B1, cyclin A, PCNA, Ki67 and cell cycle inhibitors p21, p27 and p57 in human first trimester placenta and deciduas

Histochemistry and Cell Biology ◽

10.1007/s00418-006-0160-y ◽

2006 ◽

Vol 125 (6) ◽

pp. 615-624 ◽

Cited By ~ 51

Author(s):

Emin Türkay Korgun ◽

Ciler Celik-Ozenci ◽

Nuray Acar ◽

Sevil Cayli ◽

Gernot Desoye ◽

...

Keyword(s):

Cell Cycle ◽

Cyclin A ◽

First Trimester ◽

Cyclin B1 ◽

Cell Cycle Regulators ◽

Cell Cycle Inhibitors

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Effects of water-soluble components of atmospheric particulates from rare earth mining areas in China on lung cancer cell cycle

Particle and Fibre Toxicology ◽

10.1186/s12989-021-00416-z ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Yuan Xia ◽

Xulong Zhang ◽

Dejun Sun ◽

Yumin Gao ◽

Xiaoe Zhang ◽

...

Keyword(s):

Lung Cancer ◽

Cell Cycle ◽

Rare Earth ◽

A549 Cell ◽

A549 Cells ◽

Cyclin B1 ◽

Water Soluble ◽

Differentially Expressed ◽

M Phase ◽

Cell Arrest

Abstract Background This study aims to investigate the effects of water soluble particulate matter (WSPM) on the viability and protein expression profile of human lung adenocarcinoma cell A549 in the Bayou Obo rare earth mining area, and explore the influence of WSPM on the A549 cell cycle. Results It was found that WSPM can inhibit the viability of A549 cells and induce cell arrest in the G2/M phase. Compared with controls, exposure to WSPM10 and WSPM2.5 induced 134 and 116 proteins to be differentially expressed in A549 cells, respectively. In addition, 33 and 31 differentially expressed proteins were further confirmed, and was consistent with the proteomic analysis. The most prominent enrichment in ribosome-associated proteins were presented. When RPL6, RPL13, or RPL18A gene expression was inhibited, A549 cells were arrested in the G1 phase, affecting the expression of Cyclin D1, p21, RB1, Cyclin A2, Cyclin B1, CDC25A, CDK2, CHEK2 and E2F1. Furthermore, the La3+, Ce3+, Nd3+ and F- in WSPM also inhibited the viability of A549 cells. After 24 h of exposure to 2 mM of NaF, A549 cells were also arrested in the G2/M phase, while the other three compounds did not have this effect. These four compounds affected the cell cycle regulatory factors in A549 cells, mainly focusing on effecting the expression of CDK2, CDK4, RB1, ATM, TP53 and MDM2 genes. These results are consistent with the those from WSPM exposure. Conclusions These results revealed that WSPM from rare earth mines decreased the viability of A549 cells, and induced cell cycle G2/M phase arrest, and even apoptosis, which may be independent of the NF-κB/MYD88 pathway, and be perceived by the TLR4 receptor. The dysfunction of the cell cycle is correlated to the down-expression of ribosomal proteins (RPs). However, it is not the direct reason for the A549 cell arrest in the G2/M phase. La3+, Ce3+, and F- are probably the main toxic substances in WSPM, and may be regulate the A549 cell cycle by affecting the expression of genes, such as MDM2, RB1, ATM, TP53, E2F1, CDK2 and CDK4. These results indicate the importance for further research into the relationship between APM and lung cancer.

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