scholarly journals Cell interactions in the developing somite; in vivo comparisons between amputated (AM/AM) and normal mouse embryos

1978 ◽  
Vol 31 (1) ◽  
pp. 275-291
Author(s):  
O.P. Flint ◽  
D.A. Ede

Light and electron microscopy coupled to a quantitative analysis form a powerful technique for the analysis of cell behaviour in mutant and normal tissues. Using this approach the morphology of the cells and their contacts are examined in the somites of a recessive mouse mutant, amputated, and of its normal littermates. The results of the analysis show that cell density is the same in both mutant and normal sclertome but that mutant cells tend to form small clumps whereas normal cells disperse individually. There is a correspondingly greater area of cell contact per cell in the mutant. Filopodia are equally numerous in the mutant and normal but where in the normal they stretch across wide intercellular spaces to make contact at their tips with other cells, in the mutant they form a tangled web sticking back on to the surface of the cell of origin and adjacent cells. The appearance of mutant and normal sclerotome is compared with presomitic cells and with the cells of other mutants whose abnormal development has been shown to depend on cell contact morphology and behaviour.

Development ◽  
1982 ◽  
Vol 67 (1) ◽  
pp. 113-125
Author(s):  
O. P. Flint ◽  
D. A. Ede

Facial, axial and limb development are all abnormal in the homozygous mutant mouse embryo (amputated). An interpretation of cell behaviour in vivo based on sectioned material which may explain these abnormalities has been previously suggested. In this study, somite cells cultured in vitro were found to behave exactly as predicted in this interpretation: they clump together, forming extensive areas of cell contact, and this has a profound effect on their mobility as measured by time-lapse cinemicrography. The similarity of cell behaviour in vitro and in vivo under two distinct sets of environmental conditions suggests that the abnormal cell behaviour is intrinsic to the cell, and directly linked to the mutation. The more extensive areas of cell contact formed between mutant cells suggests that the mutation changes the adhesive properties of the cell surface, but it cannot be excluded that the cells' motile apparatus is also affected.


Author(s):  
Conly L. Rieder

The behavior of many cellular components, and their dynamic interactions, can be characterized in the living cell with considerable spatial and temporal resolution by video-enhanced light microscopy (video-LM). Indeed, under the appropriate conditions video-LM can be used to determine the real-time behavior of organelles ≤ 25-nm in diameter (e.g., individual microtubules—see). However, when pushed to its limit the structures and components observed within the cell by video-LM cannot be resolved nor necessarily even identified, only detected. Positive identification and a quantitative analysis often requires the corresponding electron microcopy (EM).


1978 ◽  
Vol 17 (06) ◽  
pp. 238-248
Author(s):  
H. Beekhuis ◽  
M.A.P.C. van de Poll ◽  
A. Versluis ◽  
H. Jurjens ◽  
M.G. Woldring ◽  
...  

Investigations with bleomycin labelled with radionuclides other than 57Co in patients with cancer and in tumor-bearing animals are described. In patients 57Co-bleo appears to be a better tumor-seeking radiopharmaceutical than 111In-bleo, 99mTc-bleo or 197Hg-bleo. This can be explained by a higher stability in vivo and a better tumor-seeking property of 57Co-bleo and less disturbing activity in the cardiac pool and in bone and other normal tissues when assessing the scintigram.Results with 111In-bleo labelled in acidic solution are not essentially different from those with 111In-bleo labelled in neutral solution.Results of 197Hg-bleo are almost identical with those of 197HgCl2 regarding the tumor-seeking effect as well as the distribution in normal tissues and organs. Probably the complex of 197Hg to bleomycin is not stable in vivo. The superiority of 57Co-bleo over 99mTc-bleo, 197Hg-bleo and also over 67Cu-bleo is confirmed by experiments on tumor bearing animals.We may conclude that the indication for use of bleomycin as a tumor-seeking pharmaceutical labelled with 111In, 99mTc, 197Hg or 67Cu seems to be very limited.


2021 ◽  
Vol 12 (8) ◽  
Author(s):  
Dawei Chen ◽  
Zhenguo Zhao ◽  
Lu Chen ◽  
Qinghua Li ◽  
Jixue Zou ◽  
...  

AbstractEmerging evidence has demonstrated that alternative splicing has a vital role in regulating protein function, but how alternative splicing factors can be regulated remains unclear. We showed that the PPM1G, a protein phosphatase, regulated the phosphorylation of SRSF3 in hepatocellular carcinoma (HCC) and contributed to the proliferation, invasion, and metastasis of HCC. PPM1G was highly expressed in HCC tissues compared to adjacent normal tissues, and higher levels of PPM1G were observed in adverse staged HCCs. The higher levels of PPM1G were highly correlated with poor prognosis, which was further validated in the TCGA cohort. The knockdown of PPM1G inhibited the cell growth and invasion of HCC cell lines. Further studies showed that the knockdown of PPM1G inhibited tumor growth in vivo. The mechanistic analysis showed that the PPM1G interacted with proteins related to alternative splicing, including SRSF3. Overexpression of PPM1G promoted the dephosphorylation of SRSF3 and changed the alternative splicing patterns of genes related to the cell cycle, the transcriptional regulation in HCC cells. In addition, we also demonstrated that the promoter of PPM1G was activated by multiple transcription factors and co-activators, including MYC/MAX and EP300, MED1, and ELF1. Our study highlighted the essential role of PPM1G in HCC and shed new light on unveiling the regulation of alternative splicing in malignant transformation.


2021 ◽  
Vol 9 (2) ◽  
pp. e001364
Author(s):  
Yan Zhang ◽  
Hui Yang ◽  
Jun Zhao ◽  
Ping Wan ◽  
Ye Hu ◽  
...  

BackgroundThe activation of tumor-associated macrophages (TAMs) facilitates the progression of gastric cancer (GC). Cell metabolism reprogramming has been shown to play a vital role in the polarization of TAMs. However, the role of methionine metabolism in function of TAMs remains to be explored.MethodsMonocytes/macrophages were isolated from peripheral blood, tumor tissues or normal tissues from healthy donors or patients with GC. The role of methionine metabolism in the activation of TAMs was evaluated with both in vivo analyses and in vitro experiments. Pharmacological inhibition of the methionine cycle and modulation of key metabolic genes was employed, where molecular and biological analyses were performed.ResultsTAMs have increased methionine cycle activity that are mainly attributed to elevated methionine adenosyltransferase II alpha (MAT2A) levels. MAT2A modulates the activation and maintenance of the phenotype of TAMs and mediates the upregulation of RIP1 by increasing the histone H3K4 methylation (H3K4me3) at its promoter regions.ConclusionsOur data cast light on a novel mechanism by which methionine metabolism regulates the anti-inflammatory functions of monocytes in GC. MAT2A might be a potential therapeutic target for cancer cells as well as TAMs in GC.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Bo Jia ◽  
Junfeng Dao ◽  
Jiusong Han ◽  
Zhijie Huang ◽  
Xiang Sun ◽  
...  

Abstract Background Tongue squamous cell carcinoma (TSCC) is one of the most common oral tumors. Recently, long intergenic noncoding RNA 00958 (LINC00958) has been identified as an oncogene in human cancers. Nevertheless, the role of LINC00958 and its downstream mechanisms in TSCC is still unknown. Methods The effect of LINC00958 on TSCC cells proliferation and growth were assessed by CCK-8, colony formation, 5-Ethynyl-2′-deoxyuridline (EdU) assay and flow cytometry assays in vitro and tumor xenograft model in vivo. Bioinformatics analysis was used to predict the target of LINC00958 in TSCC, which was verified by RNA immunoprecipitation and luciferase reporter assays. Results LINC00958 was increased in TSCC tissues, and patients with high LINC00958 expression had a shorter overall survival. LINC00958 knockdown significantly decreased the growth rate of TSCC cells both in vitro and in vivo. In mechanism, LINC00958 acted as a ceRNA by competitively sponging miR-211-5p. In addition, we identified CENPK as a direct target gene of miR-211-5p, which was higher in TSCC tissues than that in adjacent normal tissues. Up-regulated miR-211-5p or down-regulated CENPK could abolish LINC00958-induced proliferation promotion in TSCC cells. Furthermore, The overexpression of CENPK promoted the expression of oncogenic cell cycle regulators and activated the JAK/STAT3 signaling. Conclusions Our findings suggested that LINC00958 is a potential prognostic biomarker in TSCC.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Alejandro Schcolnik-Cabrera ◽  
Alma Chavez-Blanco ◽  
Guadalupe Dominguez-Gomez ◽  
Mandy Juarez ◽  
Ariana Vargas-Castillo ◽  
...  

AbstractThe malignant energetic demands are satisfied through glycolysis, glutaminolysis and de novo synthesis of fatty acids, while the host curses with a state of catabolism and systemic inflammation. The concurrent inhibition of both, tumor anabolism and host catabolism, and their effect upon tumor growth and whole animal metabolism, have not been evaluated. We aimed to evaluate in colon cancer cells a combination of six agents directed to block the tumor anabolism (orlistat + lonidamine + DON) and the host catabolism (growth hormone + insulin + indomethacin). Treatment reduced cellular viability, clonogenic capacity and cell cycle progression. These effects were associated with decreased glycolysis and oxidative phosphorylation, leading to a quiescent energetic phenotype, and with an aberrant transcriptomic landscape showing dysregulation in multiple metabolic pathways. The in vivo evaluation revealed a significant tumor volume inhibition, without damage to normal tissues. The six-drug combination preserved lean tissue and decreased fat loss, while the energy expenditure got decreased. Finally, a reduction in gene expression associated with thermogenesis was observed. Our findings demonstrate that the simultaneous use of this six-drug combination has anticancer effects by inducing a quiescent energetic phenotype of cultured cancer cells. Besides, the treatment is well-tolerated in mice and reduces whole animal energetic expenditure and fat loss.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ji-wen Cheng ◽  
Li-xia Duan ◽  
Yang Yu ◽  
Pu Wang ◽  
Jia-le Feng ◽  
...  

Abstract Background Mesenchymal stem cells (MSCs) play a crucial role in cancer development and tumor resistance to therapy in prostate cancer, but the influence of MSCs on the stemness potential of PCa cells by cell–cell contact remains unclear. In this study, we investigated the effect of direct contact of PCa cells with MSCs on the stemness of PCa and its mechanisms. Methods First, the flow cytometry, colony formation, and sphere formation were performed to determine the stemness of PCaMSCs, and the expression of stemness-related molecules (Sox2, Oct4, and Nanog) was investigated by western blot analysis. Then, we used western blot and qPCR to determine the activity levels of two candidate pathways and their downstream stemness-associated pathway. Finally, we verified the role of the significantly changed pathway by assessing the key factors in this pathway via in vitro and in vivo experiments. Results We established that MSCs promoted the stemness of PCa cells by cell–cell contact. We here established that the enhanced stemness of PCaMSCs was independent of the CCL5/CCR5 pathway. We also found that PCaMSCs up-regulated the expression of Notch signaling-related genes, and inhibition of Jagged1-Notch1 signaling in PCaMSCs cells significantly inhibited MSCs-induced stemness and tumorigenesis in vitro and in vivo. Conclusions Our results reveal a novel interaction between MSCs and PCa cells in promoting tumorigenesis through activation of the Jagged1/Notch1 pathway, providing a new therapeutic target for the treatment of PCa.


2021 ◽  
Vol 12 (6) ◽  
Author(s):  
Yixin Tong ◽  
Yuan Huang ◽  
Yuchao Zhang ◽  
Xiangtai Zeng ◽  
Mei Yan ◽  
...  

AbstractAt present, colorectal cancer (CRC) has become a serious threat to human health in the world. Dipeptidyl peptidase 3 (DPP3) is a zinc-dependent hydrolase that may be involved in several physiological processes. However, whether DPP3 affects the development and progression of CRC remains a mystery. This study is the first to demonstrate the role of DPP3 in CRC. Firstly, the results of immunohistochemistry analysis showed the upregulation of DPP3 in CRC tissues compared with normal tissues, which is statistically analyzed to be positively correlated with lymphatic metastasis, pathological stage, positive number of lymph nodes. Moreover, the high expression of DPP3 predicts poor prognosis in CRC patients. In addition, the results of cell dysfunction experiments clarified that the downregulation of DPP3 significantly inhibited cell proliferation, colony formation, cell migration, and promoted apoptosis in vitro. DPP3 depletion could induce cell apoptosis by upregulating the expression of BID, BIM, Caspase3, Caspase8, HSP60, p21, p27, p53, and SMAC. In addition, downregulation of DPP3 can reduce tumorigenicity of CRC cells in vivo. Furthermore, CDK1 is determined to be a downstream target of DPP3-mediated regulation of CRC by RNA-seq, qPCR, and WB. The interaction between DPP3 and CDK1 shows mutual regulation. Specifically, downregulation of DPP3 can accentuate the effects of CDK1 knockdown on the function of CRC cells. Overexpression of CDK1 alleviates the inhibitory effects of DPP3 knockdown in CRC cells. In summary, DPP3 has oncogene-like functions in the development and progression of CRC by targeting CDK1, which may be an effective molecular target for the prognosis and treatment of CRC.


2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii295-iii295
Author(s):  
Mikaela Nevin ◽  
Janine Gallego ◽  
Xiaohua Song ◽  
Qiang Jiang ◽  
Alan Underhill ◽  
...  

Abstract BACKGROUND The identification of H3.3/H3.1K27M in most DIPG has changed our understanding of this disease. H3K27M mutations usually demonstrate global loss of H3K27 trimethylation (me3) with gain of H3K27 acetylation (ac). Single cell RNAseq has identified the putative cell of origin as oligodendroglial progenitor cells (OPC). The distalless gene family is necessary for the differentiation and tangential migration of committed neural progenitors to become GABAergic interneurons. Dlx1/Dlx2 double knockout (DKO) cells from the ganglionic eminences (GE) transplanted into a wild-type environment become oligodendrocytes. RESULTS We identified DLX2 occupancy of early (Olig2, Nkx2.2) and late (Myt1, Plp1) genes required for OPC differentiation in vivo and confirmed direct DLX2 protein-promoter DNA binding in vitro. Co-expression of Dlx2 with target sequences reduced reporter gene expression in vitro. There was increased expression of OLIG2, NKX2.2 and PLP-1 expression in vivo, consistent with de-repression in the absence of Dlx1/Dlx2 function. Transient over-expression of a Dlx2-GFP construct into murine DIPG cells from a GEMM that develops DIPG resulted in significant increases in expression of Gad isoforms with concomitant decreases in Olig2 and Nkx2.2. Dlx2-transfected mDIPG cells also demonstrated reduced migration, invasion and colony formation in vitro. Of significance, there was global restoration of H3K27me3 with corresponding loss of H3K27ac expression in transfected cells compared to controls. CONCLUSIONS DLX2 promotes GABAergic differentiation and migration while concomitantly repressing OPC differentiation in vivo. Developmental reprogramming of mDIPG cells by DLX2 demonstrates the potential role for directed differentiation strategies towards improving patient outcomes for this devastating pediatric cancer.


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