in-vitro-neuromuscular-junction-induced-from-human-induced

In vitro Neuromuscular Junction Induced from Human Induced Pluripotent Stem Cells

The neuromuscular junction (NMJ) is a specialized synapse that transmits action potentials from the motor neuron to skeletal muscle for mechanical ...

Taipei Medical University

Taipei Medical University Bilingual Education Center

Microtubules are part of cell structures that play a role in regulating the migration of cancer cells. The cellular apoptosis susceptibility (CSE1L/CAS) protein is a microtubule-associated protein that is highly expressed in cancer. We report here that CSE1L regulates the association of α-tubulin with β-tubulin and promotes the migration of MCF-7 breast cancer cells. CSE1L was associated with α-tubulin and β-tubulin in GST (glutathione S-transferase) pull-down and immunoprecipitation assays. CSE1L-GFP (green fluorescence protein) fusion protein experiments showed that the N-terminal of CSE1L interacted with microtubules. Increased CSE1L expression resulted in decreased tyrosine phosphorylation of α-tubulin and β-tubulin, increased α-tubulin and β-tubulin association, and enhanced assembly of microtubules. Cell protrusions or pseudopodia are temporary extensions of the plasma membrane and are implicated in cancer cell migration and invasion. Increased CSE1L expression increased the extension of MCF-7 cell protrusions. In vitro migration assay showed that enhanced CSE1L expression increased the migration of MCF-7 cells. Our results indicate that CSE1L plays a role in regulating the extension of cell protrusions and promotes the migration of cancer cells.

Increased cellular apoptosis susceptibility (CSE1L/CAS) protein expression promotes protrusion extension and enhances migration of MCF-7 breast cancer cells.

Survivin is an antiapoptotic molecule that is widely expressed in cancers, including hepatocellular carcinoma (HCC). Survivin has become a general therapeutic target for cancers because of its selective overexpression in a majority of tumors. However, little is known regarding the effect of survivin expression in combination with gemcitabine on HCC.

Survivin-mediated therapeutic efficacy of gemcitabine through glucose-regulated protein 78 in hepatocellular carcinoma.

Tumor-derived microvesicles are rich in metastasis-related proteases and play a role in the interactions between tumor cells and tumor microenvironment in tumor metastasis. Because shed microvesicles may remain in the extracellular environment around tumor cells, the microvesicle membrane protein may be the potential target for cancer therapy. Here we report that chromosome segregation 1-like (CSE1L) protein is a microvesicle membrane protein and is a potential target for cancer therapy. v-H-Ras expression induced extracellular signal-regulated kinase (ERK)-dependent CSE1L phosphorylation and microvesicle biogenesis in various cancer cells. CSE1L overexpression also triggered microvesicle generation, and CSE1L knockdown diminished v-H-Ras-induced microvesicle generation, matrix metalloproteinase (MMP)-2 and MMP-9 secretion and metastasis of B16F10 melanoma cells. CSE1L was preferentially accumulated in microvesicles and was located in the microvesicle membrane. Furthermore, anti-CSE1L antibody-conjugated quantum dots could target tumors in animal models. Our findings highlight a novel role of Ras-ERK signaling in tumor progression and suggest that CSE1L may be involved in the "early" and "late" metastasis of tumor cells in tumorigenesis. Furthermore, the novel microvesicle membrane protein, CSE1L, may have clinical utility in cancer diagnosis and targeted cancer therapy.

CSE1L, a novel microvesicle membrane protein, mediates Ras-triggered microvesicle generation and metastasis of tumor cells.

Colorectal carcinomas spread easily to nearby tissues around the colon or rectum, and display strong potential for invasion and metastasis. CSE1L, the chromosome segregation 1-like protein, is implicated in cancer progression and is located in both the cytoplasm and nuclei of tumor cells. We investigated the prognostic significance of cytoplasmic vs. nuclear CSE1L expression in colorectal cancer.

Correlations between cytoplasmic CSE1L in neoplastic colorectal glands and depth of tumor penetration and cancer stage.

Ras plays an important role in colorectal cancer progression. CSE1L (chromosome segregation 1-like) gene maps to 20q13, a chromosomal region that correlates with colorectal cancer development. We investigated the association of CSE1L with Ras in colorectal cancer progression.

CSE1L modulates Ras-induced cancer cell invasion: correlation of K-Ras mutation and CSE1L expression in colorectal cancer progression.

Autophagy is a survival mechanism that is activated in response to nutrient deprivation. The link between aberrant autophagy and cancer has been increasingly recognized. Survivin, an anti-apoptotic molecule, and the autophagy pathway are correlated with therapeutic responses to cancer. However, the role of autophagy in cancer progression remains unclear. Here, we generated survivin knockdown cells (survivin-KD) by introducing a short interfering RNA (siRNA) into hepatocellular carcinoma (HCC) cells, and we observed a 20 % reduction in the survival of these survivin-KD cells, as determined by MTT assay. In addition, an increased number of stress granules, increased positive staining by acridine orange and a shift in the high side scatter (SSC) cell population in flow cytometry analysis were observed in survivin-KD cells. Furthermore, electron microscopy revealed an increased number of autophagosomes in survivin-KD cells compared with scrambled control cells. Finally, we treated cells with an autophagy inhibitor, 3-MA, and observed a decrease in cell survival in survivin-KD cells compared with scrambled control cells. Our study suggests that an autophagy signal may be activated after the anti-apoptotic molecule survivin is suppressed. This finding implies that autophagy may be an alternative survival pathway in HCC cells and may provide a basis for the development of new therapeutic strategies for HCC.

Article	Year
Increased cellular apoptosis susceptibility (CSE1L/CAS) protein expression promotes protrusion extension and enhances migration of MCF-7 breast cancer cells. Experimental cell research\| PubMed ID: 20688056	2010
Survivin-mediated therapeutic efficacy of gemcitabine through glucose-regulated protein 78 in hepatocellular carcinoma. Annals of surgical oncology\| PubMed ID: 22258814	2012
CSE1L, a novel microvesicle membrane protein, mediates Ras-triggered microvesicle generation and metastasis of tumor cells. Molecular medicine (Cambridge, Mass.)\| PubMed ID: 22952058	2012
Correlations between cytoplasmic CSE1L in neoplastic colorectal glands and depth of tumor penetration and cancer stage. Journal of translational medicine\| PubMed ID: 23369209	2013
CSE1L modulates Ras-induced cancer cell invasion: correlation of K-Ras mutation and CSE1L expression in colorectal cancer progression. American journal of surgery\| PubMed ID: 23806821	2013
Silencing survivin activates autophagy as an alternative survival pathway in HCC cells. Tumour biology : the journal of the International Society for Oncodevelopmental Biology and Medicine\| PubMed ID: 25008566	2014

Li-Tzu Li

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