Rapid quantitative PCR determination of relative gene expression in tumor specimens using high-pressure liquid chromatography

Quantification of the levels of CYP2D6 mRNA in peripheral blood leukocytes by reverse transcriptase polymerase chain reaction HPLC

We developed a sensitive high performance liquid chromatography (HPLC) method for determining CYP2D6 mRNA in peripheral blood leukocytes (PBL) by using competitive reverse transcriptase polymerase chain reaction (RT-PCR). The method is specific, reproducible, and sensitive enough to quantify the absolute amount of low and high abundant CYP2D6 mRNA. The native CYP2D6 transcript and the internal standard, a CYP2D6 deletion RNA, were amplified with similar efficiency in RT-PCR. The PCR products were separated as the corresponding peaks in optimized HPLC. The coefficients of variation for competitive RT-PCR and HPLC determination were 1.5-6.5% and 0.6-2.4%, respectively, showing high reproducibility and reliability. This approach could also be applicable to the quantification of mRNA expressing on various tissues, including PBL, of which the expression levels were so low that they were hard to determine by existing agarose gel electrophoresis methods.

Adenovirus-mediated delivery of GDNF ameliorates corticospinal neuronal atrophy and motor function deficits in rats with spinal cord injury

The aim of the present study was to assess the effect of glial cell line-derived neurotrophic factor (GDNF) delivery mediated by a recombinant adenovirus (AdCMVgdnf or AdCMVlacZ) on the functional recovery and central neuronal atrophy in adult rats with spinal cord injury. Bilateral electrolytic lesions were made in the corticospinal tracts at the T10 vertebral level in a rat model. AdCMVgdnf or AdCMVlacZ was injected at the lesion site immediately after operation. After 2-3 weeks the neurological score and the inclined plane angle were significantly higher and the soma size of corticospinal motoneurons was larger in the AdCMVgdnf group compared with the AdCMVlacZ group. These results demonstrated that adenovirus-mediated delivery of GDNF could prevent the retrograde atrophy of corticospinal motoneurons and improve the motor function in rats with spinal cord injury.

Gene transfer into human keloid tissue with adeno-associated virus vector

BACKGROUND Gene transfer is a new territory for clinicians. Intractable disorders might be approached in such a way. Adeno-associated virus (AAV) vector has been transfected successfully into a variety of tissues including skin. We evaluated the ability of this vector to transfer and cause expression of the reporter gene in human keloid tissue. METHODS Human keloid specimens were injected with an AAV vector encoding beta-galactosidase and incubated for 4 weeks after injection. The presence of mRNA and beta-galactosidase enzymatic activity were assayed by reverse-transcriptase polymerase chain reaction and the X-gal technique. RESULTS Gene expression shown by reverse-transcriptase polymerase chain reaction was observed in keloid tissue 4 weeks after injection, and so was the positive X-gal staining. CONCLUSION Our results showed that AAV vector could transduce human keloid tissue effectively. Replacement of the reporter gene with a functioning gene might be feasible for keloid treatment.

Adenovirus-mediated GDNF protects cultured motoneurons from glutamate injury

The protective effects of adenovirus-mediated glia cell line-derived neurotrophic factor (GDNF) gene transaction was investigated on cultured motoneurons. First, the dose- and time-response relationship of glutamate neurotoxicity was determined on spinal motoneuron cultures. Then, the effect of the gdnf recombinant adenovirus (AdCMVgdnf) was tested in this cellular model. AdCMVgdnf at 20 MOI (multiplicity of infection) was found to significantly reduce the cell loss of motoneurons, as compared to AdCMVgdnf at 20 MOI, the recombinant adenovirus containing the marker gene lacZ. Furthermore, the adenovirus was proved to mediate erogenous gene expression using X-Gal staining and a semi-quantitative RT-PCR method. These results suggested a therapeutic potential of adenovirus vector-mediated gdnf gene therapy in human motoneuron diseases.

Interleukin-1beta induces different gene expression of stromelysin, aggrecan and tumor-necrosis-factor-stimulated gene 6 in human osteoarthritic chondrocytes in vitro

OBJECTIVE

To analyze the gene expression of osteoarthritic chondrocytes cultured in alginate after stimulation with interleukin (IL)-1beta.

METHODS

Chondrocytes were isolated from osteoarthritic cartilage obtained during total knee replacement by sequential enzymatic digestion. After suspension in alginate, cells were cultured with and without 100 pg/ml IL-1beta. Quantitative RT-PCR reaction was used to estimate the messenger RNA (mRNA) of three different metabolites [tumor-necrosis-factor-stimulated gene 6 (TSG-6), stromelysin-1 (MMP-3) and aggrecan (AGG)].

RESULTS

After having shown the precision of quantitative PCR, this method allowed us to detect IL-1beta-induced changes in mRNA of TSG-6, MMP-3 and AGG. MMP-3 was found to be the most abundant transcript, IL-1beta induced a 12-fold upregulation of MMP-3 levels compared to control, and 7-fold of TSG-6. The AGG transcript level, indicating anabolic events, was found to be downregulated by between 2- and 3-fold.

CONCLUSIONS

In our culture system, the response of osteoarthritic chondrocytes to IL-1beta is preserved. Therefore, this system might be helpful for further investigation of the influences of drugs, cytokines and growth factors, for example, on the metabolism of chondrocytes at the level of gene transcription as the most basic level of regulation.

Rapid method for relative gene expression determination in human tissues using automated capillary gel electrophoresis and multicolor detection

The aim of this study was to evaluate a direct and automated post-polymerase chain reaction (PCR) detection system to simultaneously determine the relative gene expression levels of nine cancer-related human genes. Total RNA was prepared from flash-frozen biopsies derived from human colorectal tumors or normal mucosa and reverse-transcribed to cDNA which was PCR-amplified using primer pairs corresponding to the studied genes. In each reaction, the forward primer was labeled with a fluorescent dye. The PCR products were pooled and an internal size standard with a uniquely colored fluorescent dye was added. The samples were then subjected to automated capillary gel electrophoresis. Fragment analysis software was used to calculate the relative gene expression using beta-actin as the reference gene. We found that automated capillary gel electrophoresis with multicolor detection is a rapid, accurate and highly reproducible method for separation and quantification of PCR-amplified cDNA.