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Journal ArticleDOI

Hzf and hCAS/CSE1L: making the right choice in p53-mediated tumour suppression.

01 Oct 2007-Cell Research (Nature Publishing Group)-Vol. 17, Iss: 10, pp 829-831

AboutThis article is published in Cell Research.The article was published on 2007-10-01 and is currently open access. It has received 7 citation(s) till now.

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Journal ArticleDOI
Rong Wen1, Fuhua Li1, Yusu Xie1, Shihao Li1, Jianhai Xiang1 
TL;DR: The cell apoptosis susceptibility (CAS) gene is a homolog of the yeast chromosome segregation (CSE1) gene, which functions in cell proliferation and apoptosis, which suggested that FcCAS might function as a nuclear protein.
Abstract: The cell apoptosis susceptibility (CAS) gene is a homolog of the yeast chromosome segregation (CSE1) gene, which functions in cell proliferation and apoptosis. In the present study, a homolog of CAS was cloned from Chinese shrimp Fenneropenaeus chinensis (FcCAS). The full-length FcCAS cDNA is 3534 bp and contains an open reading frame encoding 968 amino acids. The predicted tertiary FcCAS structure is highly similar to that of CSE1 from the yeast Saccharomyces cerevisiae. RT-PCR analysis showed that the FcCAS gene is expressed mainly in testis, ovary, stomach, lymphoid organs, gills, and hemocytes. RNA in situ hybridization showed that FcCAS transcripts were distributed mainly in the cytoplasm of oocytes. Western blot analysis showed that FcCAS could be detected only in testis and ovary, and its expression levels differed at different developmental stages of ovaries. Immunohistochemical analysis showed that FcCAS existed in both the cytoplasm and the nucleus, which suggested that FcCAS might function as a nuclear protein. No transcript was detected in the abnormally developed ovaries of triploid shrimp. Therefore, we inferred that the FcCAS gene might be one of the key genes that is closely related to ovary development in shrimp.

75 citations


Cites background from "Hzf and hCAS/CSE1L: making the righ..."

  • ...Recent reports have shown that CAS regulated apoptosis by affecting target genes in the P53 pathway [30, 31]....

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Journal ArticleDOI
TL;DR: An overview of the main DNA repair pathways, with special focus on the role played by homologous repair and the RAD51 recombinase protein in the cellular DNA damage response, and a survey of the most promising therapeutic strategies aimed at targeting RAD51 in experimental oncology.
Abstract: The maintenance of genome integrity is essential for any organism survival and for the inheritance of traits to offspring. To the purpose, cells have developed a complex DNA repair system to defend the genetic information against both endogenous and exogenous sources of damage. Accordingly, multiple repair pathways can be aroused from the diverse forms of DNA lesions, which can be effective per se or via crosstalk with others to complete the whole DNA repair process. Deficiencies in DNA healing resulting in faulty repair and/or prolonged DNA damage can lead to genes mutations, chromosome rearrangements, genomic instability, and finally carcinogenesis and/or cancer progression. Although it might seem paradoxical, at the same time such defects in DNA repair pathways may have therapeutic implications for potential clinical practice. Here we provide an overview of the main DNA repair pathways, with special focus on the role played by homologous repair and the RAD51 recombinase protein in the cellular DNA damage response. We next discuss the recombinase structure and function per se and in combination with all its principal mediators and regulators. Finally, we conclude with an analysis of the manifold roles that RAD51 plays in carcinogenesis, cancer progression and anticancer drug resistance, and conclude this work with a survey of the most promising therapeutic strategies aimed at targeting RAD51 in experimental oncology.

27 citations


Journal ArticleDOI
TL;DR: Results indicate that progesterone caused apoptosis and tamoxifen induced G1 arrest in ovarian cancer cells, indicating a synergistic effect on anti-cancer activity.
Abstract: Progesterone has a potential protective effect against ovarian carcinoma induced by estrogen. Progesterone is also known to cause apoptosis while tamoxifen induces growth arrest. Therefore, we attempted to determine whether combined treatment with progesterone and tamoxifen has a synergistic effect on anti-cancer activity. Although progesterone is known to cause apoptosis while tamoxifen induces growth arrest in many cancer cells, the detailed action of progesterone and tamoxifen and the anticancer effect of combined treatment have not been tested in ovarian cancer cells. Therefore, we tested the growth and apoptosis activity of progesterone and tamoxifen and the anticancer effect of combined treatment of progesterone and tamoxifen in ovarian cancer cells. Ovarian cancer cells, PA-1, were treated with progesterone, tamoxifen, or a combination of progesterone and tamoxifen. The anti-cancer effects were investigated by use of flow cytometry, terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, DNA fragmentation analysis, and Western blot analysis. We found that 100 µM progesterone induced typical apoptosis in PA-1 cells. Treatment of PA-1 cells with 10 µM tamoxifen resulted in an increase in the levels of p21, p27, p16 and phospho-pRb, indicating typical G1 arrest. Co-treatment of PA-1 cells with 100 µM progesterone and 10 µM tamoxifen resulted in typical apoptosis, similar to that induced by treatment with 100 µM progesterone alone. These results indicate that progesterone caused apoptosis and tamoxifen induced G1 arrest. Combined treatment with tamoxifen and progesterone caused apoptosis similar to that induced by treatment with progesterone alone and had no additional anti-cancer effect in ovarian cancer cells.

13 citations


Journal ArticleDOI
TL;DR: Findings show changes in CAS/CSE1L during BE progression, which may represent a potential marker for dysplasia/carcinoma and indicate its expression in BE neoplasia should be addressed.
Abstract: BACKGROUND Identifying the molecular switch responsible for the neoplastic progression of Barrett's esophagus (BE) and initiation of adenocarcinoma (ADC) is clinically essential and it will have a profound impact on patient diagnosis, prognosis, and treatment. The cellular apoptosis susceptibility gene CAS/CSE1L is overexpressed in various cancers, including a rare report on esophageal ADC; however, its expression in BE neoplasia has not been addressed. MATERIALS AND METHODS We investigated the expression of the CAS/CSE1L protein immunohistochemically in 56 esophageal resection specimens for ADC arising in BE. For each specimen, a full representative section of the invasive ADC was selected to include, when possible, BE, low-grade dysplasia (LGD) and high-grade dysplasia (HGD). Samples were stained for CAS/CSE1L expression using a rabbit polyclonal antibody recognizing the N-terminus of human CAS/CSE1L. Protein expression levels were measured using the Allred semiquantitative scoring system. The data were evaluated using χ statistical analysis. Gene expression Omnibus was queried for CAS/CSE1L and BE neoplasia. RESULTS We found minimal to absent CAS/CSE1L in all BE tissue samples; however, CAS/CSE1L was upregulated in 60% of LGD and overexpressed in HGD and ADC. The results were statistically significant (P<0.05). The localization of CAS/CSE1L protein was nuclear in BE; it became nuclear and cytoplasmic in LGD and HGD, and predominantly cytoplasmic in ADC. A similar progressive increase was observed for CAS/CSE1L gene expression. CONCLUSION These findings show changes in CAS/CSE1L during BE progression. CAS/CSE1L may represent a potential marker for dysplasia/carcinoma.

7 citations


Journal ArticleDOI
TL;DR: Observations clarified the previous conflicting results on the cell fates of the breast cells regulated by CAS and provide new insight into the role of CAS in the development of breast cancer.
Abstract: Breast cancer is the most common cancer in women. Although several studies demonstrated cellular apoptosis susceptibility protein (CAS) involved in the development of breast cancer, the underlying mechanisms of CAS regulating cell processes in the breast cancer remain elusive. In the present study, we explored the possible mechanism of CAS in contributing to the cell proliferation in the breast cancer cell line MCF-7. Knockdown of CAS led to the reduction of cell viability and proliferation. Furthermore, cell cycle was arrested in G0/G1 phase after knocking down CAS with the decrease of cyclinD1. In addition, RNA-seq analysis for the CAS knockdown cells demonstrated that total eleven genes were significantly altered (Fold changes > 2). Of note, the expression of cyp24a1 was dramatically increased in the shCAS cells compared to that of shNC cells as well as confirmed by quantitative real-time polymerase chain reaction (qPCR). These observations clarified the previous conflicting results on the cell fates of the breast cells regulated by CAS and provide new insight into the role of CAS in the development of breast cancer.

2 citations


Cites background from "Hzf and hCAS/CSE1L: making the righ..."

  • ...Apart from its role of the nuclear transport factor [19, 20], the function of CAS was found to contribute to regulate cell apoptosis [21, 22], proliferation [23], mitosis [16, 23] during multiple physiological and pathological processes such as microvesicle formation [24, 25], the development of early embryos and cancer metastasis [3, 26, 27]....

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References
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Journal ArticleDOI
14 Jul 2006-Cell
TL;DR: expression of TIGAR may modulate the apoptotic response to p53, allowing survival in the face of mild or transient stress signals that may be reversed or repaired, and the decrease of intracellular ROS levels in response to TIGar may also play a role in the ability of p53 to protect from the accumulation of genomic damage.
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1,213 citations


Journal ArticleDOI
TL;DR: The expression of ASPP is frequently downregulated in human breast carcinomas expressing wild-type p53 but not mutant p53, therefore, ASPP regulate the tumor suppression function of p53 in vivo.
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651 citations


Journal ArticleDOI
14 May 2004-Cell
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572 citations


Journal ArticleDOI
TL;DR: iASPP is an evolutionarily conserved inhibitor of p53; inhibition of iASPP by RNA-mediated interference or antisense RNA in C. elegans or human cells, respectively, induces p53-dependent apoptosis and could provide an important new strategy for treating tumors expressing wild-type p53.
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352 citations