Inhibition of platelet-derived growth factor signalling induces autophagy in malignant glioma cells

Takeuchi, Hayato; Kanzawa, Takao; Kondo, Yasuko; Kondo, Seiji

doi:10.1038/sj.bjc.6601605

Cited by 62 publications

(45 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Autophagy, on the other hand, represents a different process of selfdestruction of cytoplasm and intracellular organelles characterized by the formation of double-membrane or multimembrane autophagic vacuoles (autophagosomes), which are eventually delivered to lysosomes for bulk degradation (15). Both autophagy and apoptosis may be triggered by common signals such as cellular stress and the inhibition of growth factor signaling (16,17). One might thus suspect that the two processes use some common regulatory mechanisms.…”

Section: Discussionmentioning

confidence: 99%

Human rhomboid family-1 gene silencing causes apoptosis or autophagy to epithelial cancer cells and inhibits xenograft tumor growth

Yan¹,

Zou²,

Fang³

et al. 2008

Molecular Cancer Therapeutics

View full text Add to dashboard Cite

The rhomboid family of genes carry out a wide range of important functions in a variety of organisms. Little is known, however, about the function of the human rhomboid family-1 gene (RHBDF1). We show here that RHBDF1 function is essential to epithelial cancer cell growth. RHBDF1 mRNA level is significantly elevated in clinical specimens of invasive ductal carcinoma of the breast, and the protein is readily detectable in human breast cancer or head and neck cancer cell lines. Silencing the RHBDF1 gene with short interfering RNA (siRNA) results in apoptosis in breast cancer MDA-MB-435 cells and autophagy in head and neck squamous cell cancer 1483 cells. The treatment also leads to significant down-modulation of activated AKT and extracellular signal-regulated kinase in the cells, suggesting that critically diminished strength of these growth signals may be the key attributes of the induction of cell death. Furthermore, silencing the RHBDF1 gene in MDA-MB-435 or 1483 xenograft tumors on athymic nude mice by using i.v. administered histidine-lysine polymer nanoparticle-encapsulated siRNA results in marked inhibition of tumor growth. Our findings indicate that RHBDF1 has a pivotal role in sustaining growth signals in epithelial cancer cells and thus may serve as a therapeutic target for treating epithelial cancers. [Mol Cancer Ther 2008;7(6):1355-64]

show abstract

Section: Discussionmentioning

confidence: 99%

Human rhomboid family-1 gene silencing causes apoptosis or autophagy to epithelial cancer cells and inhibits xenograft tumor growth

Yan¹,

Zou²,

Fang³

et al. 2008

Molecular Cancer Therapeutics

View full text Add to dashboard Cite

show abstract

“…the tyrosine kinase inhibitor imatinib 139 ), inhibition of growth factor signalling (e.g. inhibition of PDGF signalling 140 ), cytotoxic chemotherapy (e.g. vinblastine 141 ) and hormonal therapy 142 .…”

Section: Autophagy In Cancermentioning

confidence: 99%

Role of the pro-survival molecule Bfl-1 in melanoma

Hind

Carter

Harris

et al. 2015

The International Journal of Biochemistry & Cell Biology

View full text Add to dashboard Cite

Melanoma, the cancer derived from the melanocytes of the skin, is becoming an ever more common cancer in the ageing population of the developed world and displays an intrinsic resistance to current therapies. This chemo resistance makes metastatic melanoma an extremely difficult cancer to treat leading to a 5 year survival rate of just 20%. As such, it is important to unearth new potential drug targets to increase the prospects for melanoma patients.Bfl-1 is a pro-survival protein of the Bcl-2 family of apoptosis regulating proteins. It has been found to be over-expressed in a small subset of chemo resistant tumours, including melanoma. Accordingly, I characterised the molecule in melanoma cells and determined its role in protecting these cells from chemotherapy-induced apoptosis. I elucidated the expression profile and half-lives of the protein and mRNA across a panel of melanoma cell-lines and healthy melanocytes. I also confirmed, using pathway specific inhibitors, that Bfl-1 was transcriptionally regulated by the NFB pathway and concluded through pulsechase experiments that Bfl-1 protein was degraded, at least in part, by the proteasome. Subcellular fractionation and indirect immunofluorescence techniques elucidated that Bfl-1 was located mostly at the mitochondria in both resting and apoptotic cells, with a diffuse level present throughout the cytoplasm. As well as characterising the protein in both melanoma cells and healthy primary melanocytes, I determined its role in the resistance of these cells to apoptosis. Over-expressed Bfl-1 was found to protect melanoma cells from apoptosis caused by a range of chemotherapeutic agents in A375 melanoma cells, which naturally expressed very low levels of Bfl-1. Further, knock down of Bfl-1 using siRNA technology in melanoma cells revealed the dependence of these cells on Bfl-1 for their resistance to certain chemotherapeutic agents currently used in melanoma treatment, including the MEK inhibitor PD901. All together, this research contributes to our understanding of Bfl-1 and highlights it as a potentially important therapeutic target in metastatic melanoma.

show abstract

“…Acidic vesicular organelles, which correlate with autophagic activity, were assessed as described previously. 29 In acridine orange-stained cells, the cytoplasm and nucleolus fluoresce bright green and dim red, whereas acidic compartments fluoresce bright red, evaluated by fluorescence microscopy (excitation filter 1 ¼ 525-625 nm).…”

Section: Methodsmentioning

confidence: 99%

Caspase-3-dependent export of TCTP: a novel pathway for antiapoptotic intercellular communication

et al. 2010

View full text Add to dashboard Cite

The apoptotic program incorporates a paracrine component of importance in fostering tissue repair at sites of apoptotic cell deletion. As this paracrine pathway likely bears special importance in maladaptive intercellular communication leading to vascular remodeling, we aimed at further defining the mediators produced by apoptotic endothelial cells (EC), using comparative and functional proteomics. Apoptotic EC were found to release nanovesicles displaying ultrastructural characteristics, protein markers and functional activity that differed from apoptotic blebs. Tumor susceptibility gene 101 and translationally controlled tumor protein (TCTP) were identified in nanovesicle fractions purified from medium conditioned by apoptotic EC and absent from purified apoptotic blebs. Immunogold labeling identified TCTP on the surface of nanovesicles purified from medium conditioned by apoptotic EC and within multivesicular blebs in apoptotic EC. These nanovesicles induced an extracellular signal-regulated kinases 1/2 (ERK 1/2)-dependent antiapoptotic phenotype in vascular smooth muscle cells (VSMC), whereas apoptotic blebs did not display antiapoptotic activity on VSMC. Caspase-3 biochemical inhibition and caspase-3 RNA interference in EC submitted to a proapoptotic stimulus inhibited the release of nanovesicles. Also, TCTP siRNAs in EC attenuated the antiapoptotic activity of purified nanovesicles on VSMC. Collectively, these results identify TCTP-bearing nanovesicles as a novel component of the paracrine apoptotic program of potential importance in vascular repair.

show abstract

Inhibition of platelet-derived growth factor signalling induces autophagy in malignant glioma cells

Cited by 62 publications

References 40 publications

Human rhomboid family-1 gene silencing causes apoptosis or autophagy to epithelial cancer cells and inhibits xenograft tumor growth

Human rhomboid family-1 gene silencing causes apoptosis or autophagy to epithelial cancer cells and inhibits xenograft tumor growth

Role of the pro-survival molecule Bfl-1 in melanoma

Caspase-3-dependent export of TCTP: a novel pathway for antiapoptotic intercellular communication

Contact Info

Product

Resources

About