scholarly journals Tissue homeostasis in sponges: quantitative analysis of cell proliferation and apoptosis

2021 ◽  
Author(s):  
Nikolai P Melnikov ◽  
Fyodor V Bolshakov ◽  
Veronika S Frolova ◽  
Ksenia V Skorentseva ◽  
Alexander V Ereskovsky ◽  
...  

Background: Tissues of multicellular animals are maintained due to a tight balance between cell proliferation and programmed cell death. Phylum Porifera is an early branching group of metazoans essential to understanding the key mechanisms of tissue homeostasis. This paper is dedicated to the comparative analysis of proliferation and apoptosis in intact tissues of two sponges belonging to distinct Porifera lineages, Halisarca dujardinii (class Demospongiae) and Leucosolenia variabilis (class Calcarea). Results: Labeled nucleotides EdU and anti-phosphorylated histone 3 antibodies reveal a considerable number of cycling cells in intact tissues of both species. The main type of cycling cells are choanocytes - flagellated cells of the aquiferous system. The rate of proliferation remains constant in areas containing choanoderm. Cell cycle distribution assessed by the quantitative DNA stain reveals the classic cell cycle distribution curve. During EdU pulse-chase experiments conducted in H. dujardinii, the contribution of the choanocytes to the total amount of EdU-positive cells decreases, while contribution of the mesohyl cells increases. These findings could indicate that the proliferation of the choanocytes is not solely limited to the renewal of the choanoderm, and that choanocytes may participate in the general cell turnover through migration. The number of apoptotic cells in intact tissues of both species is insignificant. In vivo studies in both species with TMRE and CellEvent Caspase-3/7 indicate that apoptosis might be independent of mitochondrial outer membrane permeabilization. Conclusions: A combination of confocal laser scanning microscopy and flow cytometry provides a quantitative description of cell turnover in intact sponge tissues. Intact tissues of H. dujardinii (Demospongiae) and L. variabilis (Calcarea) are highly proliferative, indicating either high rates of growth or cell turnover. Although the number of apoptotic cells is low, apoptosis could still be involved in the regular cell turnover.

2020 ◽  
Author(s):  
Chen Liu ◽  
Liang Zhong ◽  
Chenlan Shen ◽  
Xuan Chu ◽  
Xu Luo ◽  
...  

Abstract Background Increasing evidence demonstrated that long noncoding RNAs (lncRNAs) act as important factors in the regulation of cell processes and tumorigenesis. The long-noncoding RNA colorectal neoplasia differentially expressed (CRNDE) gene has been found to be related to several types of cancer. Although CRNDE is highly expressed in AML, its mechanism of action in acute myeloid leukemia (AML) is unknown. Methods The expression levels of CRNDE and miR-136-5p mRNAs were measured by quantitative real-time PCR. The effects of CRNDE knockdown on cell proliferation was assessed by the CCK8 assay, while apoptosis and cell cycle distribution were analyzed by flow cytometry. The expression of proteins related to cell cycle, cell apoptosis and MCM5 were analyzed by Western blotting. The luciferase reporter assay was used to confirm the interaction between CRNDE and miR-136-5p and between MCM5 and miR-136-5p in AML. The RNA immunoprecipitation assay was used to verify whether CRNDE exists in the miRNA mediated RISC complex. Results In this study, we used GEPIA database to confirm that CRNDE expression was significantly upregulated in AML samples. The silencing of CRNDE inhibited AML cells’ proliferation ability, increased AML cells’ apoptotic rate and arrested AML cells at the G1 phase of the cell cycle. Mechanistically, CRNDE served as a competing endogenous RNA (ceRNA) for miR-136-5p and upregulated MCM5 expression by sponging miR-136-5p. In addition, rescue assays revealed that the effects of CRNDE knockdown could be reversed by miR-136-5p inhibitors in AML cells. Conclusion Our results demonstrate that the CRNDE-miR-136-5p-MCM5 axis modulates AML progression and provide a new regulatory network of CRNDE in AML.


2020 ◽  
Author(s):  
Chen Liu ◽  
Liang Zhong ◽  
Chenlan Shen ◽  
Xuan Chu ◽  
Xu Luo ◽  
...  

Abstract Background: Increasing evidence demonstrated that long noncoding RNAs (lncRNAs) act as important factors in the regulation of cell processes and tumorigenesis. The long-noncoding RNA colorectal neoplasia differentially expressed (CRNDE) gene has been found to be related to several types of cancer. Although CRNDE is highly expressed in AML, its mechanism of action in acute myeloid leukemia (AML) is unknown.Methods: The expression levels of CRNDE and miR-136-5p mRNAs were measured by quantitative real-time PCR. The effects of CRNDE knockdown on cell proliferation was assessed by the CCK8 assay, while apoptosis and cell cycle distribution were analyzed by flow cytometry. The expression of proteins related to cell cycle, cell apoptosis and MCM5 were analyzed by Western blotting. The luciferase reporter assay was used to confirm the interaction between CRNDE and miR-136-5p and between MCM5 and miR-136-5p in AML. The RNA immunoprecipitation assay was used to verify whether CRNDE exists in the miRNA mediated RISC complex.Results: In this study, we used GEPIA database to confirm that CRNDE expression was significantly upregulated in AML samples. The silencing of CRNDE inhibited AML cells’ proliferation ability, increased AML cells’ apoptotic rate and arrested AML cells at the G1 phase of the cell cycle. Mechanistically, CRNDE served as a competing endogenous RNA (ceRNA) for miR-136-5p and upregulated MCM5 expression by sponging miR-136-5p. In addition, rescue assays revealed that the effects of CRNDE knockdown could be reversed by miR-136-5p inhibitors in AML cells. Conclusion: Our results demonstrate that the CRNDE-miR-136-5p-MCM5 axis modulates AML progression and provide a new regulatory network of CRNDE in AML.


2020 ◽  
Author(s):  
Chen Liu ◽  
Liang Zhong ◽  
Chenlan Shen ◽  
Xuan Chu ◽  
Xu Luo ◽  
...  

Abstract Background: Increasing evidence demonstrated that long noncoding RNAs (lncRNAs) act as important factors in the regulation of cell processes and tumorigenesis. The long-noncoding RNA colorectal neoplasia differentially expressed (CRNDE) gene has been found to be related to several types of cancer. Although CRNDE is highly expressed in AML, its mechanism of action in acute myeloid leukemia (AML) is unknown.Methods: The expression levels of CRNDE and miR-136-5p mRNAs were measured by quantitative real-time PCR. The effects of CRNDE knockdown on cell proliferation was assessed by the CCK8 assay, while apoptosis and cell cycle distribution were analyzed by flow cytometry. The expression of proteins related to cell cycle, cell apoptosis and MCM5 were analyzed by Western blotting. The luciferase reporter assay was used to confirm the interaction between CRNDE and miR-136-5p and between MCM5 and miR-136-5p in AML. The RNA immunoprecipitation assay was used to verify whether CRNDE exists in the miRNA mediated RISC complex.Results: In this study, we used GEPIA database to confirm that CRNDE expression was significantly upregulated in AML samples. The silencing of CRNDE inhibited AML cells’ proliferation ability, increased AML cells’ apoptotic rate and arrested AML cells at the G1 phase of the cell cycle. Mechanistically, CRNDE served as a competing endogenous RNA (ceRNA) for miR-136-5p and upregulated MCM5 expression by sponging miR-136-5p. In addition, rescue assays revealed that the effects of CRNDE knockdown could be reversed by miR-136-5p inhibitors in AML cells. Conclusion: Our results demonstrate that the CRNDE-miR-136-5p-MCM5 axis modulates AML progression and provide a new regulatory network of CRNDE in AML.


2018 ◽  
Vol 18 (2) ◽  
pp. 210-215 ◽  
Author(s):  
Mona Diab-Assaf ◽  
Josiane Semaan ◽  
Marwan El-Sabban ◽  
Soad K. Al Jaouni ◽  
Rania Azar ◽  
...  

Introduction: Adult T-cell leukemia (ATL) is an aggressive form of malignancy caused by human T- cell lymphotropic virus 1 (HTLV-1). Currently, there is no effective treatment for ATL. Thymoquinone has been reported to have anti-cancer properties. Objective: The aim of this study is to investigatthe effects of TQ on proliferation, apoptosis induction and the underlying mechanism of action in both HTLV-1 positive (C91-PL and HuT-102) and HTLV-1 negative (CEM and Jurkat) malignant T-lymphocytes. Materials and Methods: Cells were incubated with different thymoquinone concentrations for 24h. Cell cytotoxicity was assayed using the CytoTox 96® Non-Radioactive Cytotoxicity Assay Kit. Cell proliferation was determined using CellTiter 96® Non-Radioactive Cell Proliferation. Cell cycle analysis was performed by staining with propidium iodide. Apoptosis was assessed using cell death ELISA kit. The effect of TQ on p53, p21, Bcl-2 protein expression was determined using Western blot analysis while TGF mRNA expression was determined by RT-PCR. Results: At non-cytotoxic concentrations of TQ, it resulted in the inhibition of proliferation in a dose dependent manner. Flow cytometric analysis revealed a shift in the cell cycle distribution to the PreG1 phase which is a marker of apoptosis. Also TQ increase DNA fragmentation. TQ mediated its anti-proliferative effect and apoptosis induction by an up-regulation of TGFβ1, p53 and p21 and a down-regulation of TGF-α and Bcl-2α. Conclusion: Thymoquinone presents antiproliferative and proapoptotic effects in ATL cells. For this reason, further research is required to investigate its possible application in the treatment of ATL.


1996 ◽  
Vol 84 (5) ◽  
pp. 831-838 ◽  
Author(s):  
Xiao-Nan Li ◽  
Zi-Wei Du ◽  
Qiang Huang

✓ The modulation effects of hexamethylene bisacetamide (HMBA), a differentiation-inducing agent, on growth and differentiation of cells from human malignant glioma cell line SHG-44 were studied. At cytostatic doses (2.5 mM, 5 mM, 7.5 mM, and 10 mM for 15 days), HMBA exerted a marked inhibitory effect on cell proliferation. Exposure to HMBA (5 mM and 10 mM for 12 days) also resulted in an accumulation of cells in G0/G1 phase and a decrease of cells in S phase as analyzed by flow cytometry. The reversible effects of 7.5 mM HMBA and 10 mM HMBA on cell proliferation and 10 mM HMBA on disruption of cell cycle distribution were observed when HMBA was removed from culture media on Day 6 and replaced with HMBA-free media. Colony-forming efficiency (CFE) in soft agar was remarkably decreased by HMBA (2.5 mM, 5 mM, 7.5 mM, and 10 mM for 14 days), and in 7.5 mM HMBA— and 10 mM HMBA—treated cells, the CFEs were reduced to 25% and 12.5%, respectively, of that in untreated cells. Cells treated with HMBA (5 mM and 10 mM for 15 days) remained tumorigenic in athymic nude mice, but the growth rates of the xenografts were much slower than those in the control group. The effects of HMBA on cell proliferation, cell cycle distribution, CFE, and growth of xenografts were dose dependent. A more mature phenotype was confirmed by the morphological changes from spindle shape to large polygonal stellate shape and remarkably elevated expression of glial fibrillary acidic protein in cells exposed to HMBA (5 mM, 10 mM for 15 days). Our results showed that a more differentiated phenotype with marked growth arrest was induced in SHG-44 cells by HMBA.


1997 ◽  
Vol 14 (2) ◽  
pp. 61-73 ◽  
Author(s):  
Hildegard Weiß ◽  
Karl‐Heinz Jacobasch ◽  
Wolfgang Haensch ◽  
Brigitte Streller ◽  
Brigitte Hieke

The relation between proliferation and apoptosis was studied in colorectal mucosal biopsies (N=41), tubular adenomas (TA) (N=104) and tubulovillous adenomas (TVA) (N=34) from 37 FAP patients. Proliferative activity was determined by cell cycle distribution analysis. In addition, transcriptional capacity was determined by chromatin in situ testing. For both, DNA flow cytometry was used. Cycling cells were identified by immunohistochemical staining with monoclonal antibody Ki67. The existence of subdiploid apoptotic cells was derived from DNA and/or DNA/protein patterns. In a follow‐up group, the mucosa is characterised by a balance between proliferation (S % + G2M % = 19) and apoptotic cells (% = 17). The percentage of Ki67 positive cells (16%) corresponds to the percentages mentioned above. In TA, the amount of apoptotic cells remains unaltered, in TVA it decreases to 8%. At the same time, the percentage of Ki67 positive cells increases significantly in both TA and TVA (39%, 42%). With patients who underwent surgery due to clinical signs without histological evidence for malignancy, apoptotic cells in TA continue to decrease significantly (9%), without any changes in cycling cells. Only in the carcinoma‐bearing bowel, cycling cells increase to 52%. Here, the percentage of apoptotic cells in TVA reaches the lowest level (5%). A connection between proliferation and apoptosis was observed in mucosa and TVA. The process of tumorigenesis is characterised by a stepwise increase in resistance to apoptosis followed by an increase in cycling cells.


2020 ◽  
Author(s):  
Xing Zeng ◽  
Zhiquan Hu ◽  
Yuanqing Shen ◽  
Xian Wei ◽  
Jiahua Gan ◽  
...  

Abstract BackgroundAccumulating evidence indicates miR-5195-3p exerts tumor suppressive role in several tumors. However, there is limited research on the clinical significance and biological function of miR-5195-3p in prostate cancer (PCa).MethodsExpression levels of miR-5195-3p and Cyclin L1 (CCNL1) were determined using quantitative real-time PCR. The clinical significance of miR-5195-3p in PCa patients was evaluated using Kaplan-Meier survival analysis and Cox regression models. Cell proliferation and cell cycle distribution were measured by CCK-8 assay and flow cytometry, respectively. The association between miR-5195-3p and CCNL1 was analyzed by luciferase reporter assay.ResultsMiR-5195-3p expression levels were significantly downregulated in 69 paired PCa tissues compared with matched adjacent normal tissues. The decreased miR-5195-3p expression was associated with Gleason score and TNM stage, as well as worse survival prognosis. The in vitro experiments showed that miR-5195-3p overexpression suppressed the proliferation and cell cycle G1/S transition in PC-3 and DU145 cells. Elevated miR-5195-3p abundance was also demonstrated to impair tumor formation in vivo using PC-3 xenografts. Mechanistically, Cyclin L1 (CCNL1) was a direct target of miR-5195-3p in PCa cells, which was inversely correlated with miR-5195-3p in PCa tissues. Importantly, CCNL1 knockdown imitated, while overexpression reversed the effects of miR-5195-3p overexpression on PCa cell proliferation and cell cycle G1/S transition.ConclusionsOur data suggests that miR-5195-3p functions as a tumor suppressor via downregulating G1/S related CCNL1 expression in PCa.


2017 ◽  
Vol 65 (7) ◽  
pp. 1084-1088 ◽  
Author(s):  
Xiao-Jing Yu ◽  
Tie-Jun Song ◽  
Lu-Wei Zhang ◽  
Ying Su ◽  
Ke-Yu Wang ◽  
...  

Psoriasis is a chronic skin disease characterized by abnormal keratinocyte proliferation and differentiation, inflammation, and angiogenesis. Overexpression of tribbles homolog3 (TRB3), which belongs to the tribbles family of pseudokinases, has been found in several human tumors and metabolic diseases, but its role in psoriasis has not been fully clarified. The aim of this study is to investigate the expression of TRB3 in psoriasis and explore its roles in the proliferation of keratinocytes. Twenty-four patients with psoriasis vulgaris were recruited for the study. Diagnosis of psoriasis was based on clinical and histologic examinations. Immunohistochemistry and real-time reverse transcription PCR (RT-PCR) were performed to determine protein and messenger RNA (mRNA) expression of TRB3 in psoriasis lesions. 5-Bromo-2-deoxyUridine (BrdU) incorporation assay were performed for cell proliferation. Cell cycle distribution was assessed by flow cytometry analysis. The levels of TRB3 is elevated in psoriatic lesions compared with psoriatic non-lesions. The HaCat cells expressed the TRB3 gene. We found TRB3 silencing to significantly inhibit HaCat cell proliferation. Furthermore, the specific knockdown of TRB3 slowed down the cell cycle at the gap 0/first gap phase. In conclusion, our data suggest that TRB3 is overexpressed in lesions of patients with psoriasis and may be involved in the abnormal proliferation of keratinocytes. Therefore, TRB3 may be a potential therapeutic target for psoriasis.


2016 ◽  
Author(s):  
Ilona Holcomb ◽  
Gajalakshmi Dakshinamoorthy ◽  
Benjamin Liu ◽  
Marc Unger ◽  
Ramesh Ramakrishnan ◽  
...  

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