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Overexpression of peptide deformylase in breast, colon, and lung cancers.

Randhawa H, Chikara S, Gehring D, Yildirim T, Menon J, Reindl KM - BMC Cancer (2013)

Bottom Line: Colon cancer cells were treated with inhibitors of ERK, Akt, and mTOR signaling pathways and the resulting effects on PDF and MAP1D mRNA levels were determined by qPCR for colon and lung cancer cell lines.Inhibition of the MEK/ERK, but not PI3K or mTOR, pathway reduced the expression of PDF and MAP1D in both colon and lung cancer cell lines.Further, inhibition of PDF with actinonin resulted in greater reduction of breast, colon, and prostate cancer cell proliferation than non-cancer cell lines.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Biological Sciences, North Dakota State University, Fargo, ND, USA.

ABSTRACT

Background: Human mitochondrial peptide deformylase (PDF) has been proposed as a novel cancer therapeutic target. However, very little is known about its expression and regulation in human tissues. The purpose of this study was to characterize the expression pattern of PDF in cancerous tissues and to identify mechanisms that regulate its expression.

Methods: The mRNA expression levels of PDF and methionine aminopeptidase 1D (MAP1D), an enzyme involved in a related pathway with PDF, were determined using tissue panels containing cDNA from patients with various types of cancer (breast, colon, kidney, liver, lung, ovarian, prostate, or thyroid) and human cell lines. Protein levels of PDF were also determined in 2 colon cancer patients via western blotting. Colon cancer cells were treated with inhibitors of ERK, Akt, and mTOR signaling pathways and the resulting effects on PDF and MAP1D mRNA levels were determined by qPCR for colon and lung cancer cell lines. Finally, the effects of a PDF inhibitor, actinonin, on the proliferation of breast, colon, and prostate cell lines were determined using the CyQUANT assay.

Results: PDF and MAP1D mRNA levels were elevated in cancer cell lines compared to non-cancer lines. PDF mRNA levels were significantly increased in breast, colon, and lung cancer samples while MAP1D mRNA levels were increased in just colon cancers. The expression of PDF and MAP1D varied with stage in these cancers. Further, PDF protein expression was elevated in colon cancer tissue samples. Inhibition of the MEK/ERK, but not PI3K or mTOR, pathway reduced the expression of PDF and MAP1D in both colon and lung cancer cell lines. Further, inhibition of PDF with actinonin resulted in greater reduction of breast, colon, and prostate cancer cell proliferation than non-cancer cell lines.

Conclusions: This is the first report showing that PDF is over-expressed in breast, colon, and lung cancers, and the first evidence that the MEK/ERK pathway plays a role in regulating the expression of PDF and MAP1D. The over-expression of PDF in several cancers and the inhibition of cancer cell growth by a PDF inhibitor suggest this enzyme may act as an oncogene to promote cancer cell proliferation.

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Related in: MedlinePlus

PDF protein expression is elevated in colon tumor tissues. Western blotting was done to determine the expression of PDF in colon cancer tissue samples (T) relative to normal colon tissue (N) from two patients. Elevated PDF levels were found in the colon tumor samples for each patient. A β-actin antibody was used to confirm equal protein loading of the tissue samples for each patient. Two replicate experiments were performed and this image shows one representative experiment.
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Figure 5: PDF protein expression is elevated in colon tumor tissues. Western blotting was done to determine the expression of PDF in colon cancer tissue samples (T) relative to normal colon tissue (N) from two patients. Elevated PDF levels were found in the colon tumor samples for each patient. A β-actin antibody was used to confirm equal protein loading of the tissue samples for each patient. Two replicate experiments were performed and this image shows one representative experiment.

Mentions: To verify that the increased PDF mRNA levels translated to increased PDF protein levels, we screened two sets of colon cancer tissues for PDF expression. Matched colon cancer and normal colon tissue sets were obtained from two patients at the VA Hospital in Fargo, ND in accordance with IRB policies. Western blotting for PDF revealed a striking elevation of PDF expression in the tumor sample of both of these patients relative to their matched normal colon tissue (Figure 5).


Overexpression of peptide deformylase in breast, colon, and lung cancers.

Randhawa H, Chikara S, Gehring D, Yildirim T, Menon J, Reindl KM - BMC Cancer (2013)

PDF protein expression is elevated in colon tumor tissues. Western blotting was done to determine the expression of PDF in colon cancer tissue samples (T) relative to normal colon tissue (N) from two patients. Elevated PDF levels were found in the colon tumor samples for each patient. A β-actin antibody was used to confirm equal protein loading of the tissue samples for each patient. Two replicate experiments were performed and this image shows one representative experiment.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3722014&req=5

Figure 5: PDF protein expression is elevated in colon tumor tissues. Western blotting was done to determine the expression of PDF in colon cancer tissue samples (T) relative to normal colon tissue (N) from two patients. Elevated PDF levels were found in the colon tumor samples for each patient. A β-actin antibody was used to confirm equal protein loading of the tissue samples for each patient. Two replicate experiments were performed and this image shows one representative experiment.
Mentions: To verify that the increased PDF mRNA levels translated to increased PDF protein levels, we screened two sets of colon cancer tissues for PDF expression. Matched colon cancer and normal colon tissue sets were obtained from two patients at the VA Hospital in Fargo, ND in accordance with IRB policies. Western blotting for PDF revealed a striking elevation of PDF expression in the tumor sample of both of these patients relative to their matched normal colon tissue (Figure 5).

Bottom Line: Colon cancer cells were treated with inhibitors of ERK, Akt, and mTOR signaling pathways and the resulting effects on PDF and MAP1D mRNA levels were determined by qPCR for colon and lung cancer cell lines.Inhibition of the MEK/ERK, but not PI3K or mTOR, pathway reduced the expression of PDF and MAP1D in both colon and lung cancer cell lines.Further, inhibition of PDF with actinonin resulted in greater reduction of breast, colon, and prostate cancer cell proliferation than non-cancer cell lines.

View Article: PubMed Central - HTML - PubMed

Affiliation: Department of Biological Sciences, North Dakota State University, Fargo, ND, USA.

ABSTRACT

Background: Human mitochondrial peptide deformylase (PDF) has been proposed as a novel cancer therapeutic target. However, very little is known about its expression and regulation in human tissues. The purpose of this study was to characterize the expression pattern of PDF in cancerous tissues and to identify mechanisms that regulate its expression.

Methods: The mRNA expression levels of PDF and methionine aminopeptidase 1D (MAP1D), an enzyme involved in a related pathway with PDF, were determined using tissue panels containing cDNA from patients with various types of cancer (breast, colon, kidney, liver, lung, ovarian, prostate, or thyroid) and human cell lines. Protein levels of PDF were also determined in 2 colon cancer patients via western blotting. Colon cancer cells were treated with inhibitors of ERK, Akt, and mTOR signaling pathways and the resulting effects on PDF and MAP1D mRNA levels were determined by qPCR for colon and lung cancer cell lines. Finally, the effects of a PDF inhibitor, actinonin, on the proliferation of breast, colon, and prostate cell lines were determined using the CyQUANT assay.

Results: PDF and MAP1D mRNA levels were elevated in cancer cell lines compared to non-cancer lines. PDF mRNA levels were significantly increased in breast, colon, and lung cancer samples while MAP1D mRNA levels were increased in just colon cancers. The expression of PDF and MAP1D varied with stage in these cancers. Further, PDF protein expression was elevated in colon cancer tissue samples. Inhibition of the MEK/ERK, but not PI3K or mTOR, pathway reduced the expression of PDF and MAP1D in both colon and lung cancer cell lines. Further, inhibition of PDF with actinonin resulted in greater reduction of breast, colon, and prostate cancer cell proliferation than non-cancer cell lines.

Conclusions: This is the first report showing that PDF is over-expressed in breast, colon, and lung cancers, and the first evidence that the MEK/ERK pathway plays a role in regulating the expression of PDF and MAP1D. The over-expression of PDF in several cancers and the inhibition of cancer cell growth by a PDF inhibitor suggest this enzyme may act as an oncogene to promote cancer cell proliferation.

Show MeSH
Related in: MedlinePlus