scholarly journals ANALOGY IN GROWTH BETWEEN LATE PASSAGE HUMAN EMBRYONIC AND EARLY PASSAGE HUMAN ADULT FIBROBLASTS

1969 ◽  
Vol 43 (2) ◽  
pp. 374-377 ◽  
Author(s):  
A. Macieira-Coelho ◽  
J. Ponten
2004 ◽  
Vol 78 (11) ◽  
pp. 5720-5727 ◽  
Author(s):  
Astrid C. Baege ◽  
Gary L. Disbrow ◽  
Richard Schlegel

ABSTRACT Human ectocervical cells, following retroviral transduction with the human papillomavirus type 16 E6/E7 oncogenes, are altered in their array of transcribed cellular genes, including increased mRNA for the insulin-like growth factor binding protein 3 (IGFBP-3). IGFBP-3 expression is associated with cellular senescence, and its addition to many cell types inhibits growth or induces apoptosis. By immunoblotting and enzyme-linked immunosorbent assay methods, we demonstrate that late-passage, immortalized E6/E7-transduced cells secrete high levels of IGFBP-3 (25 ng/ml), which represent a 500-fold increase compared to levels in early-passage, nonimmortalized transduced cells (<0.05 ng/ml). Concomitantly, these late-passage cervical cells exhibit an increase in sensitivity to IGF-1, including enhanced phosphorylation of the IGF receptor (IGF-R) and insulin receptor substrate as well as increased DNA synthesis (5-fold) and cell proliferation (3.7-fold). However, there was no change in the level of IGF-R in these cells (surface or total), and the cells did not synthesize IGF-1, indicating that these arms of the IGF pathway were independently regulated and not responsible for the augmented signaling. Consistent with a causal relationship between IGFBP-3 expression and enhanced IGF-1 responses, we found that early-passage cells could be converted to the late-passage, IGF-1-responsive phenotype by preincubation with IGFBP-3. Thus, in contrast to findings with some cell types, IGFBP-3 expression in cervical cells is associated with augmented IGF-1 signaling and cell proliferation and correlates with the timing of cellular immortalization.


2005 ◽  
Vol 25 (10) ◽  
pp. 4046-4061 ◽  
Author(s):  
Tatsuo Oikawa ◽  
Masaru Okuda ◽  
Zhiyong Ma ◽  
Rakesh Goorha ◽  
Hajime Tsujimoto ◽  
...  

ABSTRACT Elimination of the regulatory mechanism underlying numeral homeostasis of centrosomes, as seen in cells lacking p53, results in abnormal amplification of centrosomes, which increases the frequency of chromosome segregation errors, and thus contributes to the chromosome instability frequently observed in cancer cells. We have previously reported that p53−/− mouse cells in prolonged culture undergo genomic convergence similar to that observed during tumor progression; early-passage p53−/− cells are karyotypically heterogeneous due to extensive chromosome instability associated with centrosome amplification, while late-passage p53−/− cells are aneuploid yet karyotypically homogeneous and chromosomally stable. Moreover, they contain numerically normal centrosomes. Through the microarray analysis of early- and late-passage p53−/− cells, we identified the BubR1 spindle checkpoint protein, which plays a critical role in suppression of centrosome amplification and stabilization of chromosomes in late-passage p53−/− cells. Up-regulation of BubR1 augments the checkpoint function, which effectively senses the spindle/chromosome aberrations associated with centrosome amplification. We further found that BubR1 transcription is largely controlled by p53. In early-passage p53−/− cells, BubR1 expression is low and the checkpoint function in response to microtubule toxin is considerably compromised. In late-passage cells, however, regaining of BubR1 expression restores the checkpoint function to mitotic aberrations caused by microtubule toxin. Our studies demonstrate the molecular aspect of genomic convergence in cultured cells, providing critical information for understanding the stepwise progression of tumors.


2004 ◽  
Vol 78 (16) ◽  
pp. 8687-8700 ◽  
Author(s):  
Karthikeyan Veeraraghavalu ◽  
Mark Pett ◽  
Rekha V. Kumar ◽  
Pradip Nair ◽  
Annapoorni Rangarajan ◽  
...  

ABSTRACT Infection by high-risk human papillomaviruses (HPV) and persistent expression of viral oncogenes E6 and E7 are causally linked to the development of cervical cancer. These oncogenes are necessary but insufficient for complete transformation of human epithelial cells in vivo. Intracellular Notch1 protein is detected in invasive cervical carcinomas (ICC), and truncated Notch1 alleles complement the function of E6/E7 in the transformation of human epithelial cells. Here we investigate potential mechanisms of Notch activation in a human cervical neoplasia. We have analyzed human cervical lesions and serial passages of an HPV type 16-positive human cervical low-grade lesion-derived cell line, W12, that shows abnormalities resembling those seen in cervical neoplastic progression in vivo. Late-passage, but not early-passage, W12 and progression of the majority of human high-grade cervical lesions to ICC showed upregulation of Notch ligand and Jagged1 and downregulation of Manic Fringe, a negative regulator of Jagged1-Notch1 signaling. Concomitantly, an increase in Notch/CSL (CBF1, Suppressor of Hairless, Lag1)-driven reporter activity and a decrease in Manic Fringe upstream regulatory region (MFng-URR)-driven reporter activity was observed in late-passage versus early passage W12. Analysis of the MFng-URR revealed that Notch signaling represses this gene through Hairy Enhancer of Split 1, a transcriptional target of the Notch pathway. Expression of Manic Fringe by a recombinant adenovirus, dominant-negative Jagged1, or small interfering RNA against Jagged1 inhibits the tumorigenicity of CaSki, an ICC-derived cell line that was previously shown to be susceptible to growth inhibition induced by antisense Notch1. We suggest that activation of Notch in cervical neoplasia is Jagged1 dependent and that its susceptibility to the influence of Manic Fringe is of therapeutic value.


2018 ◽  
Vol 2018 ◽  
pp. 1-13 ◽  
Author(s):  
Ningxia Zhu ◽  
Keng Huang ◽  
Yang Liu ◽  
Huan Zhang ◽  
En Lin ◽  
...  

Dermal papilla (DP) cells play a vital role in hair follicle (HF) development and postnatal hair cycling. However, the abilities are lost on further culture. Recent studies have demonstrated significant influences of posttranscriptional regulation by microRNA (miRNA) on HF development. The current study aims to investigate how miRNAs regulate Wnt/β-catenin to control HF inductivity of DP cells by performing microarray analysis in early- and late-passage DP cells and transfecting with miRNAs inhibitor or mimic. Results showed early-passage DP cells strongly expressed miRNAs related to inhibition of noncanonical Wnt pathways. In late-passage DP cells, miRNAs capable of inhibiting the canonical Wnt/β-catenin pathway were upregulated, in addition to the miRNAs targeting the noncanonical Wnt pathway. Moreover, we verified that β-catenin expression was downregulated by miR-195-5p overexpression in dose manner. Meanwhile LRP6 expression was downregulated in both protein and mRNA as well as the genes involved in the hair inductivity of DP cells. These results suggest that the appearance of miRNAs that suppress the Wnt/β-catenin pathway may be responsible for the loss of ability of DP cells in culture and miR-195-5p is the potential key factor involved in regulating HF inductivity of DP cells.


2015 ◽  
Vol 15 (1) ◽  
pp. 263-265 ◽  
Author(s):  
Ras Trokovic ◽  
Jere Weltner ◽  
Timo Otonkoski

Cells ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 2118
Author(s):  
Hytham N. Fageeh

Background: Dental pulp tissue within the central cavity of the tooth is composed of dental pulp stem cells (DPSC). These mesenchymal stem cells have good proliferative as well as differentiation potential. DPSC has been isolated even from teeth with inflamed pulps and is found to retain their proliferative and differentiation potential. Little research is available about the viability and differentiation potential of DPSC obtained from teeth with periodontitis. In the present study, the aim was to compare the morphological features, stem cell marker (MSC) expression, proliferation rate, migratory and wound healing properties, osteogenic and chondrogenic differentiation potential of DPSCs obtained from periodontally healthy teeth (hDPSCs) and periodontitis affected teeth (pDPSCs). Methods: Dental pulp tissue was obtained from periodontally healthy volunteers (n = 3) and patients with periodontitis undergoing extraction of mobile teeth (n = 3). DPSC were isolated using the explant technique and cultured. All the experiments were performed at early passage (Passage 2), late passage (Passage 6) and after cryopreservation. Morphological features of the hDPSCs and pDPSCs were ascertained using microscopy. The expression of cell surface stem cell markers was assessed by the flow cytometry method. The proliferation and growth rate of the cells were assayed by plotting a growth curve from 0–13 days of culture. The migratory characteristics were assessed by wound scratch assay. Osteogenic and chondrogenic differentiation of the cells was assessed using standard protocols with and without induction. Results: DPSCs were successfully obtained from periodontally healthy teeth (hDPSC) and periodontitis-affected teeth (pDPSCs). The data suggests that there were no morphological differences observed in early passage cells between the two cohorts. Cryopreservation did change the morphology of pDSPCs. There was no significant difference in the positive expression of mesenchymal markers CD73, CD90 and CD105 in early passage cells. However, serial passaging and cryopreservation affected the marker expression in pDPSCs. A faint expression of hematopoietic stem cell markers CD34, CD45 and MHC class II antigen HLA-DR was observed in both the cell types. The expression of HLA-DR is upregulated in pDPSCs compared to hDPSC. A significantly slower growth rate and slower wound healing properties was observed in pDPSCs compared to hDPSC. In late passage and after cryopreservation, the migratory ability of pDPSCs was found to be increased drastically. There was no significant difference in osteogenic potential between the two cell types. However, the chondrogenic potential of pDPSCs was significantly lower compared to hDPSc. Yet, pDPSCs showed enhanced osteogenesis and chondrogenesis at late passage as well as after cryopreservation. Conclusion: The results of this novel study shed light on the isolation of viable DPSC from periodontitis-affected teeth. These cells exhibit a slower growth rate and migratory characteristics compared to their healthy counterparts. There was no difference in osteogenic potential but a reduction in chondrogenic potential was seen in pDPSCs compared to hDPSC. The findings reveal that DPSC from periodontitis-affected teeth presents an easy and viable option for regenerative medicine application. Some additional nutritive factors and protocols may be required to attain better regenerative benefits while using pDPSCs.


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