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Results for “Multiplex PCR”

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PubMed2001

Regulation of keratinocyte growth factor receptor and androgen receptor in epithelial cells of the human prostate.

PURPOSE: Stromal-epithelial interactions of growth factors and the androgen receptor may have implications for the pathophysiology of benign and neoplastic transformation of the human adult prostate. We investigated a possible interaction of keratinocyte growth factor with its receptor as well as with the androgen receptor signaling pathway in human prostatic epithelial cells. MATERIALS AND METHODS: Human prostatic epithelial cells were obtained from explant primary culture, established in DU145 cell conditioned medium and maintained in keratinocyte serum-free medium with supplements. Epithelial cells were characterized by light and electron microscopy, and immunocytochemical study using epithelial and mesenchymal markers. Androgen receptor, keratinocyte growth factor receptor and keratinocyte growth factor messenger RNA expression was measured by polymerase chain reaction (PCR). The response to 0.01 to 10 nM. dihydrotestosterone, 10 microM. flutamide and 1 to 1,000 ng./ml. keratinocyte growth factor was tested by [3H] thymidine assay. The difference in keratinocyte growth factor receptor and androgen receptor gene expression after treatment with and without keratinocyte growth factor and flutamide were determined by quantitative multiplex PCR and quantitated using densitometry analysis. RESULTS: Immunocytochemical and electron microscopy characterization revealed typical epithelial differentiation. PCR showed keratinocyte growth factor receptor and androgen receptor expression in epithelial cultured cells but no keratinocyte growth factor expression. Epithelial cells showed a significant time and dose dependent stimulation of cell proliferation with keratinocyte growth factor and dihydrotestosterone (p <0.05). When combined with the anti-androgen flutamide the effect of 100 ng./ml. keratinocyte growth factor was significantly decreased (p <0.05). At 100 ng./ml. keratinocyte growth factor quantitative multiplex PCR revealed stimulated keratinocyte growth factor receptor and androgen receptor messenger RNA expression. CONCLUSIONS: These results show that keratinocyte growth factor up-regulates the keratinocyte growth factor and androgen receptors in the absence of androgen. Thus, the androgen signaling pathway may be activated by growth factors such as keratinocyte growth factor in an androgen deficient environment.

Androgen Antagonists↗

PubMed2005

Microarray analysis of Escherichia coli O157:H7.

AIM: To establish the rapid, specific, and sensitive method for detecting O157:H7 with DNA microchips. METHODS: Specific oligonucleotide probes (26-28 nt) of bacterial antigenic and virulent genes of E. coli O157:H7 and other related pathogen genes were pre-synthesized and immobilized on a solid support to make microchips. The four genes encoding O157 somatic antigen (rfbE), H7 flagellar antigen (fliC) and toxins (SLT1, SLT2) were monitored by multiplex PCR with four pairs of specific primers. Fluorescence-Cy3 labeled samples for hybridization were generated by PCR with Cy3-labeled single prime. Hybridization was performed for 60 min at 45 degrees. Microchip images were taken using a confocal fluorescent scanner. RESULTS: Twelve different bacterial strains were detected with various combinations of four virulent genes. All the O157:H7 strains yielded positive results by multiplex PCR. The size of the PCR products generated with these primers varied from 210 to 678 bp. All the rfbE/fliC/SLT1/SLT2 probes specifically recognized Cy3-labeled fluorescent samples from O157:H7 strains, or strains containing O157 and H7 genes. No cross hybridization of O157:H7 fluorescent samples occurred in other probes. Non-O157:H7 pathogens failed to yield any signal under comparable conditions. If the Cy3-labeled fluorescent product of O157 single PCR was diluted 50-fold, no signal was found in agarose gel electrophoresis, but a positive signal was found in microarray hybridization. CONCLUSION: Microarray analysis of O157:H7 is a rapid, specific, and efficient method for identification and detection of bacterial pathogens.

Escherichia coli Infections↗

PubMed1993

[Antepartum diagnosis of pseudohypertrophic muscular dystrophy using 14 sets of primers].

We used fourteen sets of primers to detect the gene deletion of 27 clinically diagnosed DMD patients by multiplex PCR technic. The detection rate was 59%. We found that the deletion region was more concentrated in the region of exon 43 to 52. The data was discussed. Twenty-two mothers of the twenty-seven affected children were pregnant again, and prenatal diagnosis was done by multiplex PCR of the DNA of the chorionic villi. Four affected fetuses were found and aborted.

Child↗

PubMed2003

A polymerase chain reaction (PCR) assay specific for Streptococcus suis based on the gene encoding the glutamate dehydrogenase.

Polymerase chain reaction (PCR) primers that flank a 688-bp segment within the glutamate dehydrogenase gene (gdh) of Streptococcus suis type 2 could amplify efficiently the DNA of all 306 (100%) clinical S. suis isolates tested (pigs, n=305; human, n=1) encompassing all serotypes obtained from diverse organs, and geographic origins. When DNA from other bacteria were used as templates for amplification, no product was detected indicating specificity of the primers. Multiplex PCR was developed using the gdh gene primer pair and primers that targeted the gene encoding S. suis capsular biosynthesis (cps). This strategy enabled the detection of strains belonging to serotypes 1/2, 1, 2, 7, and 9, respectively. Using the multiplex-PCR technique, 12 out of 14 (86%) isolates that were previously identified as non-typable S. suis (based on biochemical reactions and serology) gave positive PCR results of which four were positive for serotype 7, three for serotype 2, and five for S. suis strains that belong to other serotypes. Retest results of all 14 isolates by several veterinary laboratories were identical with PCR and confirmed that the two non-PCR reactive isolates belonged to strains of other streptococcal species. These results indicated that PCR improved species determination and can thus be used as a reliable species-specific molecular diagnostic reagent for the accurate identification of S. suis isolates and a serotype-specific method for the detection of strains of serotypes 1/2, 1, 2, 7, and 9, respectively. The PCR method therefore has potential clinical and epidemiological applications.

DNA Primers↗

PubMed2025

Distribution and molecular characterization of integron classes from Escherichia coli and Klebsiella pneumoniae isolates in Sulaymaniyah province of Iraq.

UNLABELLED: The environmental pollution from the misuse of antimicrobial drugs is fueling selection pressure in bacteria, thereby exacerbating the threat to global health. In Iraq, the situation is made worse by the poor implementation of the World Health Organization's Global Antimicrobial Resistance and Use Surveillance System (WHO-GLASS). Consequently, this study aimed to increase surveillance of the spread of antimicrobial resistance in Sulaymaniyah, Iraq. A total of 296 Enterobacteriaceae comprising 147 Klebsiella pneumoniae and 149 Escherichia coli were isolated from humans, poultry, and dairy farms. The isolates were screened using multiplex PCR to assess the prevalence of the clinically important integron integrase (intI) classes and antimicrobial resistance genes (ARGs) of commonly used antibiotics. Remarkably, 81.14% of the isolates carried at least 2 ARGs, 10.47% intI1, and 3.72% intI2. No intI3 was detected. A total of 663 ARGs were identified using multiplex PCR in the two Enterobacteriaceae: beta-lactamase genes were 43%, tetracycline resistance genes 25.20%, sulfonamide resistance gene 16.10%, quinolone resistance gene 10.2%, and aminoglycoside resistance genes 5.7%. K. pneumoniae harbored more integrons and ARGs than E. coli, thus posing a higher antimicrobial resistance threat in this province. This study underscores the importance of implementing more stringent WHO-GLASS and antibiotic stewardship to end the multidrug resistance crisis in Iraq. IMPORTANCE: These data are about the prevalence of integrons and resistance genes, helping to fill a significant gap in global surveillance efforts. Results can be used by global health authorities and the World Health Organization to develop national and international antimicrobial resistance (AMR) control strategies. The study is important because integrons are key genetic platforms that capture and disseminate antibiotic resistance genes among bacteria. In addition, Escherichia coli and Klebsiella spp. are among the top causes of hospital- and community-acquired infections, especially urinary tract infections, bloodstream infections, and pneumonia. Therefore, it will be riskier when these bacteria have a high rate of integrons and resistance genes because it impedes treatments during infection. Another importance of this study is that the study was carried out in Iraq. Iraq, like many low- and middle-income countries, faces challenges with unregulated antibiotic use, leading to high rates of AMR.

Escherichia coli↗

PubMed2004

Development of a multiplex PCR-SSP method for Killer-cell immunoglobulin-like receptor genotyping.

Killer-cell immunoglobulin-like receptors (KIRs) on natural killer (NK) cells recognize groups of HLA class I alleles. Recent work suggests that KIR genotype may affect the outcome of hematopoietic stem-cell transplants and that prospective KIR typing maybe of benefit in future matching of donors and recipients. A simple and informative KIR genotyping method was developed using a multiplex polymerase chain reaction-sequence-specific primer strategy. This method contains four multiplex reactions for detecting all functional KIR genes, including some 2DS4 variants that harbor a common deletion. Primer pairs were designed to provide short amplicons (108-565 bp) that can be analyzed by agarose gel electrophoreses or by automated electrophoretic systems. This method was evaluated in a blinded survey with the NK/KIR Phase II QC Panel (a total of 16 cell lines) from the 14th International Histocompatibility Workshop (IHWS), and the results are 100% concordant with the consensus genotype. Results in further KIR genotyping of 20 reference cell lines from the 10th IHWS were consistent with previously published genotypes, matching those of one study in instances where different genotypes have been previously reported. The genotypes obtained in this study may be helpful to other labs developing KIR genotyping methods in resolving typing discrepancies and in detecting common deletion variants of 2DS4. This method can save labor and reagent costs. It provides good results from partially degraded template DNA due to short amplicons in this method. It is convenient to use in both clinical and research laboratories.

DNA↗

PubMed2004

Pseudocohnilembus persalinus (Ciliophora: Scuticociitida) is an additional species causing scuticociliatosis in olive flounder Paralichthys olivaceus.

In the present study, Pseudocohnilembus persalinus was first reported as a species causing scuticociliatosis in olive flounder Paralichthys olivaceus. Based on the stained specimens, P. persalinus was clearly differentiated from Uronema marinum, which has been shown to be a cause of scuticociliatosis in farmed olive flounder in Korea from its characteristic oral infraciliature structure. The 1754 bp small subunit ribosomal RNA (SS rRNA) gene sequence of P. persalinus showed 95% homology with the partial sequence of P. hargisi SS rRNA. Moreover, multiplex PCR based on the species-specific amplification of the SS rRNA gene sequence enabled us to distinguish P. persalinus from U. marinum in a simple and rapid manner. P. persalinus was clearly differentiated from U. marinum even when the host was infected simultaneously with both species. These data suggest that the multiplex PCR procedure would make it possible to avoid the cumbersome and time-consuming procedures of morphological analysis for the definitive identification of ciliates.

Animals↗

PubMed1990

Fast Multiplex polymerase chain reaction on boiled clinical samples for rapid viral diagnosis.

An assessment of optimal conditions for rapid simultaneous amplification of multiple human papillomavirus (HPV) sequences has been made using Thermus aquaticus DNA polymerase. All variables of practical value were studied by amplifying known target-sequences from ten-fold dilutions of well characterized cell lines. In our hands, Fast Multiplex PCR (FM-PCR), the technique of running multiple PCR reactions simultaneously with minimum incubation time at each temperature, was highly sensitive (amplification factor = 5 x 10(9) after 50 cycles), specific (100%) and reproducible (100%) for several microbiological applications. Diagnosis was generally obtained in less than 5 h after sampling. The results show that, after optimization of assay conditions, efficiency and specificity of Multiplex PCR depends exclusively on the primers design and concentration of the primers.

Base Sequence↗

PubMed1996

Homozygous deletion of mouse homolog of p16/CDKN2 gene on chromosome 4 in mouse liver epithelial cells in culture.

The culture of hepatocytes isolated from C3H mouse liver results in the spontaneous development of colonies of liver epithelial cells that possess some features of the hepatocytes. These liver epithelial cells frequently have a loss of chromosome 4, and become neoplasms which are hepatocellular carcinomas by transfection with the activated c-Ha-ras gene. The suppression of malignant phenotypes by mouse chromosome 4 has already been shown by fusion between normal and malignant mouse cells. We established a total of six liver epithelial cell lines from C3H mice in order to investigate the presence of a tumor suppressor gene(s) on chromosome 4 in mouse hepatocarcinogenesis, and performed an allelotype analysis in seven microsatellites on chromosome 4 by the comparative multiplex PCR method. The result of analysis revealed that three of the six liver epithelial cells had allelic imbalances in four microsatellite loci, especially, two liver epithelial cell lines showed homozygous deletion in the D4MIT77 locus. Then, we investigated the status of the mouse homolog of p16/CDKN2 gene (mouse p16) on chromosome 4 by the comparative multiplex PCR method, and detected the homozygous deletion in two liver epithelial cell lines. Our result thus supports the theory that alterations of tumor suppressor gene(s) located on chromosome 4 may play a role in mouse hepatocarcinogenesis. Mouse p16, which is an inhibitor of cyclin dependent kinase 4, may suppress the cancer development in mouse hepatocarcinogenesis, or suppress liver cell immortalization.

Animals↗

PubMed2002

[A high-throughput SNP typing system for genome-wide association studies].

SNPs are useful markers for identifying genes responsible for and/or associated with common diseases, and for directing personalized medical care. Furthermore, because they are so frequent in the genome and can be genotyped quite easily, SNPs can serve as markers for a whole genome association study. However, one of the most difficult issues to be solved for whole-genome association studies using SNPs is reduction of the amount of genomic DNA for genotyping. The presently available technologies require too much genomic DNA to be practical. To overcome this problem, we combined the Invader assay with multiplex PCR performed in the presence of Taq polymerase antibody as well as a novel 384-well card system that reduces the reaction volume. We amplified 96 genomic DNA fragments simultaneously in a single tube, and analyzed each SNP using the Invader assay. Since we used 10-20 nanograms of genomic DNA as a template for multiplex PCR, the amount needed to assay one SNP was only 0.1-0.2 nanograms. Our results strongly indicate the feasibility of undertaking genome-wide association studies using blood samples of only 5-10 milliliters. Using these technologies, which allow us to perform as many as 450,000 typings in one day, our system should let us identify the genes responsible for many diseases and/or pharmacological responsiveness.

Biotechnology↗

PubMed1994

[Prenatal diagnosis of Duchenne's muscular dystrophy fetus at risk].

Prenatal diagnosis of Duchenne's muscular dystrophy (DMD) have been carried out on 12 fetus at risk. The gene mutations have been identified by hybridization with cDNA probes and/or multiplex PCR. The fetus examined were 7 males and 3 females. Three of the male fetus inherited the same deleted mutations as the probands, and other 4 appeared normal. Among the 3 female fetus, one carried a deleted gene, two were considered normal. The diagnosis of the fetus were confirmed after birth or abortion. As the multiplex PCR can quickly detect about 98% of the deletions on the dystrophin gene, it is not only an idea method for screening the gene deletion but can also be applied to prenatal diagnosis immediately after the nature of the deletion have been identified among the probands. The strategy of prenatal diagnosis of DMD in our country was also discussed.

DNA Probes↗

PubMed2006

Recovery methods for detection and quantification of Campylobacter depend on meat matrices and bacteriological or PCR tools.

Campylobacter is one of the main causes of human foodborne bacterial disease associated with meat consumption in developed countries. Therefore, the most effective approach for recovery and detection of Campylobacter from meat should be determined. Two hundred ninety pork skin and chine samples were inoculated with Campylobacter jejuni NCTC 11168 and two strains of Campylobacter coli. Campylobacter cells were then recovered from suspensions and enumerated by direct plating. Campylobacter recovery was evaluated by comparing results for two methods of sample collection (swabbing and mechanical pummeling) and three recovery fluids (peptone water, 5% glucose serum, and demineralized water). End-point multiplex PCR was performed to evaluate the compatibility of the recovery fluids with direct PCR detection techniques. Mean recovery ratios differed significantly between pork skin and chine samples. Ratios were higher for mechanical pummeling (0.53 for pork skin and 0.49 for chine) than for swabbing (0.31 and 0.13, respectively). For pork skin, ratios obtained with peptone water (0.50) and with glucose serum (0.55) were higher than those obtained with demineralized water (0.16). Significant differences were not observed for chine samples. Direct multiplex PCR detection of Campylobacter was possible with pork skin samples. The tools for Campylobacter recovery must be appropriate for the meat matrix to be evaluated. In this study, less than 66% of inoculated Campylobacter was recovered from meat. This underestimation must be taken into account for quantitative risk analysis of Campylobacter infection.

Animals↗

PubMedDate not supplied

Laser microdissection and microsatellite analysis of colorectal adenocarcinomas.

BACKGROUND: Microsatellite instability (MSI) is an important marker in colorectal cancer. The analysis may be difficult if the tumour is heterogeneous or only scarce material is available. The aim of this study was to apply laser microdissection (LMD) to MSI analysis in an attempt to allow diagnosis in these situations. MATERIALS AND METHODS: Twenty-two primary tumours and eight lymph node metastases from twenty patients were laser microdissected and MSI analysis was performed with an optimised multiplex PCR. Differences in allelic size between tumour and blood were evaluated to determine the MSI status. RESULTS: The method proved efficient in as little as 4,000 microm3 formalin-treated and paraffin-embedded tumour tissue. The result of microsatellite analysis was independent of sample location in the primary tumour and its metastasis. CONCLUSION: LMD followed by a multiplex PCR is a useful method for MSI analysis in cases of tumour heterogeneity and scarce tumour material.

Adenocarcinoma↗

PubMed2000

Frequency data on four tetrameric STR loci D18S1270, D14S608, D16S3253 and D21S1437 in a Korean population.

We present the results of a population study in Korea for four new tetrameric short tandem repeat (STR) loci employing multiplex PCR amplification, polyacrylamide gel electrophoresis of the PCR products and silver staining, which allow single base pair resolution and rapid typing. The loci tested were D18S1270, D14S608, D16S3253 and D21S1437 and all loci showed no significant deviations from Hardy-Weinberg equilibrium in more than 100 unrelated Koreans. This allelic frequency data can be used in forensic analyses and paternity tests to estimate the frequency of a multiplex PCR based DNA profile in the Korean population.

Base Sequence↗

PubMed2006

Emergence and spread of two distinct clonal groups of multidrug-resistant Escherichia coli in a veterinary teaching hospital in Australia.

Multidrug-resistant Escherichia coli (MDREC) expressing AmpC beta-lactamases have emerged as a cause of opportunistic infections in dogs. Following a cluster of extraintestinal infections caused by two distinct clonal groups (CGs) of bla(CMY)-producing MDREC, a 12-month infection control study was undertaken at a veterinary teaching hospital in Brisbane, Australia. Swabs from the rectum of hospitalized dogs (n=780), hospital staff (n=16) and the hospital environment (n=220) were plated onto selective agar to obtain multidrug-resistant (MDR) coliforms. These were then tested by multiplex PCR for E. coli uspA, bla(CMY) and the class 1 integron-associated dfrA17-aadA5 gene cassette for rapid identification of MDREC CG 1 (positive for all three genes) and CG 2 (positive for uspA and bla(CMY) only). A total of 16.5 % of the dog rectal swabs and 4.1% of the hospital environmental swabs yielded MDREC, and on the basis of multiplex PCR, PFGE and plasmid profiling, these were confirmed to belong to either CG 1 or CG 2. Both CG 1 and CG 2 isolates were obtained from clinical cases of extraintestinal infection and rectal swabs from hospitalized dogs over the same period of time, whereas only CG 1 isolates were obtained from the hospital environment. Both CGs were prevalent during the first 6 months, but only CG 2 was isolated during the second 6 months of the study. Two isolates obtained from rectal swabs of staff working in the hospital belonged to CG 2, with one of the isolates possessing the same REDP as nine isolates from dogs, including six isolates associated with cases of extraintestinal infection. CG 1 isolates belonged to E. coli serotypes O162 : H-, OR : H- or Ont : H-, whereas CG 2 isolates belonged to O153 : HR, OR : HR or OR : H34. These results confirm that in this particular outbreak, canine MDREC were highly clonal and CG 2 MDREC may colonize both humans and dogs.

Animals↗

PubMed2005

Characterization of the flexible genome complement of the commensal Escherichia coli strain A0 34/86 (O83 : K24 : H31).

Colonization by the commensal Escherichia coli strain A0 34/86 (O83 : K24 : H31) has proved to be safe and efficient in the prophylaxis and treatment of nosocomial infections and diarrhoea of preterm and newborn infants in Czech paediatric clinics over the past three decades. In searching for traits contributing to this beneficial effect related to the gut colonization capacity of the strain, the authors have analysed its genome by DNA-DNA hybridization to E. coli K-12 (MG1655) genomic DNA arrays and to 'Pathoarrays', as well as by multiplex PCR, bacterial artificial chromosome (BAC) library cloning and shotgun sequencing. Four hundred and ten E. coli K-12 ORFs were absent from A0 34/86, while 72 out of 456 genes associated with pathogenicity islands of E. coli and Shigella were also detected in E. coli A0 34/86. Furthermore, extraintestinal pathogenic E. coli-related genes involved in iron uptake and adhesion were detected by multiplex PCR, and genes encoding the HlyA and cytotoxic necrotizing factor toxins, together with 21 genes of the uropathogenic E. coli 536 pathogenicity island II, were identified by analysis of 2304 shotgun and 1344 BAC clone sequences of A0 34/86 DNA. Multiple sequence comparisons identified 31 kb of DNA specific for E. coli A0 34/86; some of the genes carried by this DNA may prove to be implicated in the colonization capacity of the strain, enabling it to outcompete pathogens. Among 100 examined BAC clones roughly covering the A0 34/86 genome, one reproducibly conferred on the laboratory strain DH10B an enhanced capacity to persist in the intestine of newborn piglets. Sequencing revealed that this BAC clone carried gene clusters encoding gluconate and mannonate metabolism, adhesion (fim), invasion (ibe) and restriction/modification functions. Hence, the genome of this clinically safe and highly efficient colonizer strain appears to harbour many 'virulence-associated' genes. These results highlight the thin line between bacterial 'virulence' and 'fitness' or 'colonization' factors, and question the definition of enterobacterial virulence factors.

Animals↗

PubMed1992

Polymerase chain reaction and other methods to detect hot-spot and multiple gene mutations.

Gene mutations responsible for main genetic diseases as Duchenne/Becker muscular dystrophy or cystic fibrosis, and involved in more important diseases like cancer or cardiac diseases have been identified. Direct DNA tests can now be performed for these disorders. However, despite the knowledge of the exact alteration of the DNA sequence in these diseases, incorporating DNA analysis into large screening programs has been hindered by technical difficulties since each different mutation requires a different probe to be detected. To overcome these problems the polymerase chain reaction technique (PCR) has been proposed. Multiplex PCR procedure is possible and consists of simultaneously amplifying several separate DNA sequences (the upper limit of the number of multiplex reactions that can be executed at one time is not known; eight or nine separate DNA sequences amplified have already been described). Another approach is to directly sequence the gene mutations generally concentrated in 'hot-spot' regions. This way it is possible to identify numerous mutations using only one micro-sequencing reaction (50-100 nucleotides). New generations of very sophisticated systems like capillary electrophoresis or non-isotopic, but very sensitive, microsequencing systems should allow in a near future to withdraw the use of PCR for this purpose.

Base Sequence↗

PubMed2001

The bmi-1 oncoprotein is differentially expressed in non-small cell lung cancer and correlates with INK4A-ARF locus expression.

Genes of the polycomb group function by silencing homeotic selector genes that regulate embryogenesis. In mice, downregulation of one of the polycomb genes, bmi-1, leads to neurological alterations and severe proliferative defects in lymphoid cells, whilst bmi-1 overexpression, together with upregulation of myc-1, induces lymphoma. An oncogenic function has been further supported in primary fibroblast studies where bmi-1 overexpression induces immortalization due to repression of p16/p19ARF, and where together with H-ras, it readily transforms MEFs. It was the aim of this study to assess the expression of bmi-1 in resectable non-small cell lung cancer (NSCLC) in association with p16 and p14ARF (=human p19ARF). Tumours (48 resectable NSCLC (32 squamous, 9 adeno-, 2 large cell, 4 undifferentiated carcinomas and 1 carcinoid); stage I, 29, II, 7, III, 12; T1, 18, T2, 30; differentiation: G1 12, G2 19, G3 17) were studied by immunohistochemistry for protein expression and by comparative multiplex PCR for gene amplification analysis. In tumour-free, normal lung tissue from patients, weak - moderate bmi-1 staining was seen in some epithelial cells, lymphocytes, glandular cells and in fibroblasts, whereas blood, endothelial, chondrocytes, muscle cells and adipocytes did not exhibit any bmi-1 expression. In tumours, malignant cells were negative/weakly, moderately and strongly positive in 20, 22 and 6 cases, respectively. As assessed by multiplex PCR, bmi-1 gene amplification was not the reason for high-level bmi-1 expression. Tumours with moderate or strong bmi-1 expression were more likely to have low levels of p16 and p14ARF (P = 0.02). Similarly, tumours negative for both, p16 and p14ARF, exhibit moderate-strong bmi-1 staining. 58% of resectable NSCLC exhibit moderate-high levels of bmi-1 protein. The inverse correlation of bmi-1 and the INK4 locus proteins expression (p16/p14ARF) supports a possible role for bmi-1 misregulation in lung carcinogenesis.

Aged↗