Clinical Validation of the Vitro HPV Screening Assay for Its Use in Primary Cervical Cancer Screening.

Many scientific societies have issued guidelines to introduce population-based cervical cancer screening with HPV testing. The Vitro HPV Screening assay is a fully automatic multiplex real-time PCR test targeting the L1 GP5+/GP6+ region of HPV genome. The assay detects 14 high risk (HR) HPV genotypes, identifying individual HPV16 and HPV18 genotypes, and the HPV-positive samples for the other 12 HR HPV types are subsequently genotyped with the HPV Direct Flow Chip test. Following international guidelines, the aim of this study was to validate the clinical accuracy of the Vitro HPV Screening test on ThinPrep-collected samples for its use as primary cervical cancer screening, using as comparator the validated cobas® 4800 HPV test. The non-inferiority analysis showed that the clinical sensitivity and specificity of the Vitro HPV Screening assay for a diagnosis of cervical intraepithelial neoplasia of grade 2 or worse (CIN2+) were not inferior to those of cobas® 4800 HPV (p = 0.0049 and p < 0.001 respectively). The assay has demonstrated a high intra- and inter-laboratory reproducibility, also among the individual genotypes. The Vitro HPV Screening assay is valid for cervical cancer screening and it provides genotyping information on HPV-positive samples without further sample processing in a fully automated workflow.

How to prevent human papillomavirus-related oropharyngeal cancer?

PURPOSE OF REVIEW: Human papillomavirus (HPV) is responsible of the increasing incidence rates of oropharyngeal squamous cell carcinoma (OPSCC) in high-income countries. This significant epidemiological change requires several and diverse prevention strategies. RECENT FINDINGS: The cervical cancer prevention model is the paradigm of HPV-related cancer, and its success provides encouragement for the development of similar methods to prevent HPV-related OPSCC. However, there are some limitations that hinder its application in this disease. Here, we review the primary, secondary and tertiary prevention of HPV-related OPSCC and discuss some directions for future research. SUMMARY: The development of new and targeted strategies to prevent HPV-related OPSCC is needed since they could definitely have a direct impact on the reduction of morbidity and mortality of this disease.

Concordance of p16INK4a and E6*I mRNA among HPV-DNA-Positive Oropharyngeal, Laryngeal, and Oral Cavity Carcinomas from the ICO International Study.

Background: Tests or test algorithms for diagnosing HPV-driven oral cavity and laryngeal head and neck carcinomas (HNC) have not been yet validated, and the differences among oral cavity and laryngeal sites have not been comprehensively evaluated. We aimed to assess the utility of a diagnostic algorithm for the detection of HPV-driven oral cavity (OCC), oropharyngeal (OPC) and laryngeal (LC) carcinomas using HPV-DNA testing followed by p16INK4a immunohistochemistry, taking E6*I mRNA detection as the reference standard. Methods: Formalin-fixed paraffin-embedded OCC, OPC, and LC carcinomas were collected from pathology archives in 29 countries. All samples were subjected to histopathological evaluation, DNA quality control, and HPV-DNA detection. All HPV-DNA-positive samples (including 78 OCC, 257 OPC, and 51 LC out of 3680 HNC with valid HPV-DNA results) were also tested for p16INK4a immunohistochemistry and E6*I mRNA. Three different cutoffs of nuclear and cytoplasmic staining were evaluated for p16INK4a: (a) >25%, (b) >50%, and (c) ≥70%. The concordance of p16INK4a and E6*I mRNA among HPV-DNA-positive OCC, OPC, and LC cases was assessed. Results: A total of 78 OCC, 257 OPC, and 51 LC were HPV-DNA-positive and further tested for p16INK4a and E6*I mRNA. The percentage of concordance between p16INK4a (cutoff ≥ 70%) and E6*I mRNA among HPV-DNA-positive OCC, OPC, and LC cases was 79.5% (95% CI 69.9−89.1%), 82.1% (95% CI 77.2−87.0%), and 56.9% (95% CI 42.3−71.4%), respectively. A p16INK4a cutoff of >50% improved the concordance although the improvement was not statistically significant. For most anatomical locations and p16INK4a cutoffs, the percentage of discordant cases was higher for HPV16- than HPV-non16-positive cases. Conclusions: The diagnostic algorithm of HPV-DNA testing followed by p16INK4a immunohistochemistry might be helpful in the diagnosis of HPV-driven OCC and OPC, but not LC. A different p16INK4a expression pattern was observed in those cases HPV-DNA-positive for types other than HPV16, as compared to HPV16-positive cases. Our study provides new insights into the use HPV-DNA, p16INK4a, and HPV-E6*I mRNA for diagnosing an HPV-driven HNC, including the optimal HPV test or p16INK4a cutoffs to be used. More studies are warranted to clarify the role of p16INK4a and HPV status in both OPC and non-OPC HNC.

The combined use of EFS, GPX2, and SPRR1A expression could distinguish favorable from poor clinical outcome among epithelial-like head and neck carcinoma subtypes.

BACKGROUND: We aimed at identifying molecular markers predictive of clinical outcome in patients with head and neck cancer based on the expression profile of cells showing epithelial-like (EL) or mesenchymal-like (ML) phenotypes. MATERIALS AND METHODS: We analyzed the association between EL and ML cells and migration, drug resistance, or tumor growth. The differential gene expression profile between cell types was used to build a model to stratify patients according to survival. RESULTS: EL cells were sensitive to cisplatin and cetuximab, showed low migration, and generated squamous differentiated tumors in mouse. A differential 93-gene expression signature between ML and EL cells was used to build a three-gene (EFS, GPX2, and SPRR1A) survival model by analyzing the RNA-seq data of the TCGA-HNSC project. Its prognostic value was confirmed in two independent cohorts. CONCLUSION: EFS, GPX2, and SPRR1A are prognostic markers able to distinguish clinical outcome among subtypes sharing an EL phenotype.

Human papillomavirus in premalignant oral lesions: No evidence of association in a Spanish cohort.

BACKGROUND: Human papillomavirus (HPV) is the cause of a fraction of head and neck squamous cell carcinoma. Although this relation is well-known, it is still not clear the role of HPV in premalignant oral lesions such as oral lichen planus (OLP) and dysplasia. We aimed to evaluate the HPV-DNA prevalence and type distribution in a set of oral biopsies obtained from patients diagnosed with OLP and dysplasia, as well as the role of HPV in these lesions. METHODS: A retrospective cohort of all premalignant oral lesions consecutively diagnosed from March 30th 1995 to May 21st 2014 at Hospital of Bellvitge and Odontological University Hospital of Bellvitge was identified and classified in four groups: OLP (groups 1 and 2) and dysplasias (groups 3 and 4) that progressed or not to invasive cancer during follow-up. A random selection targeting 25 cases was aimed to be performed for each group. All selected cases were subjected to pathological evaluation, DNA quality control and HPV-DNA detection. HPV-DNA positive samples were further subject to p16INK4a analysis. RESULTS: A total of 83 cases yielded a valid HPV-DNA result. From those, 7 and 34 cases were OLP that progressed or not to invasive cancer during follow-up, whereas 24 and 18 cases were displasias that progressed or not to invasive cancer during follow-up, respectively. HPV-DNA was detected in 4 samples (3 dysplastic lesions and 1 OLP). Two samples were HPV16 positive (2%), 1 sample HPV18 positive (1%) and 1 sample (1%) was HPV indeterminate. Two out of four HPV-DNA positive cases had high p16INK4a expression and none of the HPV positive cases progressed to invasive cancer during long-term follow-up. CONCLUSIONS: We found a low HPV-DNA attributable fraction in premalignant lesions of the oral cavity, suggesting that HPV is unlikely to play a significant role in oral carcinogenesis in our setting.

Effect of serpinE1 overexpression on the primary tumor and lymph node, and lung metastases in head and neck squamous cell carcinoma.

BACKGROUND: Serpin Family E Member 1 (SerpinE1) overexpression associates with poor clinical outcome in head and neck squamous cell carcinoma (HNSCC) patients. This study analyzed the role of serpinE1 in HNSCC dissemination. METHODS: We studied the phenotypic characteristics and dissemination of HNSCC cells overexpressing serpinE1 using an orthotopic model and the association between serpinE1 overexpression and clinicopathological variables in patients included in The Cancer Genome Atlas database. RESULTS: SerpinE1 overexpression increased proliferation, tumor budding, and the stromal component, while inhibiting apoptosis in primary tumors. It also enhanced the affectation and metastatic growth in lymph nodes, and the dispersion and growth of metastatic foci in the lung. High serpinE1 expression was associated with larger tumor size, undifferentiated tumors, lymph node metastasis, extracapsular spread, and the presence of perineural and angiolymphatic invasion. CONCLUSION: SerpinE1 overexpression promotes tumor aggressiveness and metastatic dissemination to lymph nodes and lung consistently with its association with poor outcome in HNSCC patients.

CXCR7 expression in diffuse large B-cell lymphoma identifies a subgroup of CXCR4+ patients with good prognosis.

The CXCR4/CXCL12 axis has been extensively associated with different types of cancer correlating with higher aggressiveness and metastasis. In diffuse large B-cell lymphoma (DLBCL), the expression of the chemokine receptor CXCR4 is involved in the dissemination of malignant B cells and is a marker of poor prognosis. CXCR7 is a chemokine receptor that binds to the same ligand as CXCR4 and regulates de CXCR4-CXCL12 axis. These findings together with the report of CXCR7 prognostic value in several tumor types, led us to evaluate the expression of CXCR7 in diffuse large B-cell lymphoma biopsies. Here, we describe that CXCR7 receptor is an independent prognostic factor that associates with good clinical outcome. Moreover, the expression of CXCR7 associates with increased survival in CXCR4+ but not in CXCR4- DLBCL patients. Thus, the combined immunohistochemical evaluation of both CXCR7 and CXCR4 expression in DLBCL biopsies may improve their prognostic value as single markers. Finally, we show that CXCR7 overexpression in vitro is able to diminish DLBCL cell survival and increase their sensitivity to antitumor drugs. Hence, further studies on the CXCR7 receptor may establish its role in DLBCL and the molecular mechanisms that modulate CXCR4 activity.

Double positivity for HPV-DNA/p16ink4a is the biomarker with strongest diagnostic accuracy and prognostic value for human papillomavirus related oropharyngeal cancer patients.

BACKGROUND: The etiologic role of human papillomaviruses (HPV) in oropharyngeal cancer (OPC) is well established. Nevertheless, information on survival differences by anatomic sub-site or treatment remains scarce, and it is still unclear the HPV-relatedness definition with best diagnostic accuracy and prognostic value. METHODS: We conducted a retrospective cohort study of all patients diagnosed with a primary OPC in four Catalonian hospitals from 1990 to 2013. Formalin-fixed, paraffin-embedded cancer tissues were subjected to histopathological evaluation, DNA quality control, HPV-DNA detection, and p16INK4a/pRb/p53/Cyclin-D1 immunohistochemistry. HPV-DNA positive and a random sample of HPV-DNA negative cases were subjected to HPV-E6*I mRNA detection. Demographic, tobacco/alcohol use, clinical and follow-up data were collected. Multivariate models were used to evaluate factors associated with HPV positivity as defined by four different HPV-relatedness definitions. Proportional-hazards models were used to compare the risk of death and recurrence among HPV-related and non-related OPC. RESULTS: 788 patients yielded a valid HPV-DNA result. The percentage of positive cases was 10.9%, 10.2%, 8.5% and 7.4% for p16INK4a, HPV-DNA, HPV-DNA/HPV-E6*I mRNA, and HPV-DNA/p16INK4a, respectively. Being non-smoker or non-drinker was consistently associated across HPV-relatedness definitions with HPV positivity. A suggestion of survival differences between anatomic sub-sites and treatments was observed. Double positivity for HPV-DNA/p16INK4a showed strongest diagnostic accuracy and prognostic value. CONCLUSIONS: Double positivity for HPV-DNA/p16INK4a, a test that can be easily implemented in the clinical practice, has optimal diagnostic accuracy and prognostic value. Our results have strong clinical implications for patients' classification and handling and also suggest that not all the HPV-related OPC behave similarly.

Prognostic value of CD45 transcriptional expression in head and neck cancer.

INTRODUCTION: Tumor-infiltrating lymphocytes (TILs) have a recognized antitumor activity in head and neck squamous cell carcinoma (HNSCC). CD45 is one of the most highly expressed proteins in lymphocytes. We carry out a study to assess the prognostic value of transcriptional expression of CD45 in HNSCC. MATERIAL AND METHODS: We determined the transcriptional expression of CD45 in 160 consecutive HNSCC patients and compared the TIL values according to the CD45 expression. RESULTS: Five-year disease-free survival for patients with a high transcriptional expression of CD45 (n = 107) was 62.4% and for patients with a low expression (n = 53) it was 36.2% (P = 0.003). Patients with a high expression of CD45 had a better local recurrence-free survival and disease-specific survival. The results of a multivariate analysis showed that patients with a low expression of CD45 had 2.0-fold high risk of recurrence (95% CI 1.2-3.2, P = 0.003). In oropharyngeal carcinomas, HPV-positive tumors showed a higher transcriptional CD45 expression than HPV-negative tumors. Tumors with high CD45 expression had immunohistochemical TIL scores significantly higher than those with low CD45 expression. CONCLUSION: According to our results, CD45 expression is a potential marker for tumor outcome in HNSCC patients.

The natural history of human papillomavirus infection.

Human papillomavirus (HPV) is a small double-stranded DNA virus that commonly infects humans. The oncogenic characteristics of HPV derive from the oncoproteins E6 and E7 that act inhibiting p53 and pRB tumor suppressors. About 5% of all cancers worldwide are attributable mainly to those known as high-risk, including HPV types 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, and 59. Infection with HPV is common after sexual initiation, but the majority of HPV infections do not cause symptoms or disease and are cleared within 12-24 months post-infection. Only a small fraction of those infections that persist or progress to a preneoplastic lesion result in cancer. Persistence of HPV infection is needed to start the oncogenic process. Clearance of infection is common in young adults. Viral load and viral type are the main cofactors for progression from infection to cervical intraepithelial lesions and cancer. Smoking, hormonal exposure, and HIV are additional exposures that increase the risk of progression to cancer. The adverse health effects of HPV infections can be largely controlled through vaccination and screening.

Targeting Conserved Genes in Alternaria Species.

Real-time polymerase chain reaction (PCR) is a molecular biology technique based on the detection of the fluorescence produced by a reporter molecule, which increases as the reaction proceeds proportionally to the accumulation of the PCR product within each amplification cycle. The fluorescent reporter molecules include dyes that bind to the double-stranded DNA (i.e., SYBR® Green) or sequence-specific probes (i.e., Molecular Beacons or TaqMan® Probes). Real-time PCR provides a tool for accurate and sensitive quantification of target fungal DNA. Here, we describe a TaqMan real-time PCR method for specific detection and quantification of Alternaria spp. The method uses Alternaria-specific primers and probe, targeting the internal transcribed spacer regions ITS1 and ITS2 of the rRNA gene, and a positive amplification control based on 18S rRNA gene.

uPA/uPAR and SERPINE1 in head and neck cancer: role in tumor resistance, metastasis, prognosis and therapy.

There is strong evidence supporting the role of the plasminogen activator system in head and neck squamous cell carcinoma (HNSCC), particularly of its uPA (urokinase plasminogen activator) / uPAR (urokinase plasminogen activator receptor) and SERPINE1 components. Overexpression of uPA/uPAR and SERPINE1 enhances tumor cell migration and invasion and plays a key role in metastasis development, conferring poor prognosis. The apparent paradox of uPA/uPAR and its inhibitor SERPINE1 producing similar effects is solved by the identification of SERPINE1 activated signaling pathways independent of uPA inhibition. Both uPA/uPAR and SERPINE1 are directly linked to the induction of epithelial-to-mesenchymal transition, the acquisition of stem cell properties and resistance to antitumor agents. The aim of this review is to provide insight on the deregulation of these proteins in all these processes.We also summarize their potential value as prognostic biomarkers or potential drug targets in HNSCC patients. Concomitant overexpression of uPA/uPAR and SERPINE1 is associated with a higher risk of metastasis and could be used to identify patients that would benefit from an adjuvant treatment. In the future, the specific inhibitors of uPA/uPAR and SERPINE1, which are still under development, could be used to design new therapeutic strategies in HNSCCs.

Cancer-specific uptake of a liganded protein nanocarrier targeting aggressive CXCR4+ colorectal cancer models.

Unliganded drug-nanoconjugates accumulate passively in the tumor whereas liganded nanoconjugates promote drug internalization in tumor cells via endocytosis and increase antitumor efficacy. Whether or not tumor cell internalization associates with enhanced tumor uptake is still under debate. We here compared tumor uptake of T22-GFP-H6, a liganded protein carrier targeting the CXCR4 receptor, and the unliganded GFP-H6 carrier in subcutaneous and metastatic colorectal cancer models. T22-GFP-H6 had a higher tumor uptake in primary tumor and metastatic foci than GFP-H6, with no biodistribution or toxicity on normal tissues. T22-GFP-H6 was detected in target CXCR4+ tumor cell cytosol whereas GFP-H6 was detected in tumor stroma. SDF1-α co-administration switched T22-GFP-H6 internalization from CXCR4+ tumor epithelial cells to the stroma. Therefore, the incorporation of a targeting ligand promotes selective accumulation of the nanocarrier inside target tumor cells while increasing whole tumor uptake in a CXCR4-dependent manner, validating T22-GFP-H6 as a CXCR4-targeted drug carrier.

CKMT1 and NCOA1 expression as a predictor of clinical outcome in patients with advanced-stage head and neck squamous cell carcinoma.

BACKGROUND: We studied the association between the expression of a subset of previously identified genes and clinical outcome in patients with head and neck cancer. METHODS: We analyzed by reverse transcriptase-polymerase chain reaction (RT-PCR) the expression of 89 genes in tumor biopsies from stage III to IVa/b chemotherapy treated patients (n = 46). Two additional cohorts analyzed by RNAseq (The Cancer Genome Atlas [TCGA] project; n = 371) or immunohistochemistry (IHC; n = 73) were used to validate results. RESULTS: Thirty genes were associated with local-recurrence or progression-free survival. The best multi-gene decision-tree model to predict local recurrence included nuclear receptor coactivator 1 (NCOA1) and serum-amyloid A2 (SAA2) expression, whereas the best model to predict disease recurrence included creatine kinase mitochondrial 1 (CKMT1) and metal-regulatory transcription factor 1 (MTF1). Both models were associated with cancer-specific survival. Results were confirmed analyzing the RNAseq data included in the TCGA project. CKMT1 and NCOA1 were identified as independent risk factors for survival in an independent cohort analyzed by immunohistochemistry. CONCLUSION: CKMT1 and NCOA1 expression has prognostic significance in advanced-stage head and neck carcinoma. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1392-E1403, 2016.

Enhanced cell migration and apoptosis resistance may underlie the association between high SERPINE1 expression and poor outcome in head and neck carcinoma patients.

High SERPINE1 expression is a common event in head and neck squamous cell carcinoma (HNSCC); however, whether it plays a role in determining clinical outcome remains still unknown. We studied SERPINE1 as a prognostic marker in two HNSCC patient cohorts. In a retrospective study (n = 80), high expression of SERPINE1 was associated with poor progression-free (p = 0.022) and cancer-specific (p = 0.040) survival. In a prospective study (n = 190), high SERPINE1 expression was associated with poor local recurrence-free (p = 0.022), progression-free (p = 0.002) and cancer-specific (p = 0.006) survival. SERPINE1 expression was identified as an independent risk factor for progression-free survival in patients treated with chemo-radiotherapy or radiotherapy (p = 0.043). In both patient cohorts, high SERPINE1 expression increased the risk of metastasis spread (p = 0.045; p = 0.029). The association between SERPINE1 expression and survival was confirmed using the HNSCC cohort included in The Cancer Genome Atlas project (n = 507). Once again, patients showing high expression had a poorer survival (p < 0.001). SERPINE1 over-expression in HNSCC cells reduced cell proliferation and enhanced migration. It also protected cells from cisplatin-induced apoptosis, which was accompanied by PI3K/AKT pathway activation. Downregulation of SERPINE1 expression had the opposite effect. We propose SERPINE1 expression as a prognostic marker that could be used to stratify HNSCC patients according to their risk of recurrence.

Higher metastatic efficiency of KRas G12V than KRas G13D in a colorectal cancer model.

Although all KRas (protein that in humans is encoded by the KRas gene) point mutants are considered to have a similar prognostic capacity, their transformation and tumorigenic capacities vary widely. We compared the metastatic efficiency of KRas G12V (Kirsten rat sarcoma viral oncogene homolog with valine mutation at codon 12) and KRas G13D (Kirsten rat sarcoma viral oncogene homolog with aspartic mutation at codon 13) oncogenes in an orthotopic colorectal cancer (CRC) model. Following subcutaneous preconditioning, recombinant clones of the SW48 CRC cell line [Kras wild-type (Kras WT)] expressing the KRas G12V or KRas G13D allele were microinjected in the mouse cecum. The percentage of animals developing lymph node metastasis was higher in KRas G12V than in KRas G13D mice. Microscopic, macroscopic, and visible lymphatic foci were 1.5- to 3.0-fold larger in KRas G12V than in KRas G13D mice (P < 0.05). In the lung, only microfoci were developed in both groups. KRas G12V primary tumors had lower apoptosis (7.0 ± 1.2 vs. 7.4 ± 1.0 per field, P = 0.02), higher tumor budding at the invasion front (1.2 ± 0.2 vs. 0.6 ± 0.1, P = 0.04), and a higher percentage of C-X-C chemokine receptor type 4 (CXCR4)-overexpressing intravasated tumor emboli (49.8 ± 9.4% vs. 12.8 ± 4.4%, P < 0.001) than KRas G13D tumors. KRas G12V primary tumors showed Akt activation, and ß5 integrin, vascular endothelial growth factor A (VEGFA), and Serpine-1 overexpression, whereas KRas G13D tumors showed integrin ß1 and angiopoietin 2 (Angpt2) overexpression. The increased cell survival, invasion, intravasation, and specific molecular regulation observed in KRas G12V tumors is consistent with the higher aggressiveness observed in patients with CRC expressing this oncogene.

CXCR4 expression enhances diffuse large B cell lymphoma dissemination and decreases patient survival.

The chemokine receptor CXCR4 has been implicated in the migration and trafficking of malignant B cells in several haematological malignancies. Over-expression of CXCR4 has been identified in haematological tumours, but data concerning the role of this receptor in diffuse large B cell lymphoma (DLBCL) are lacking. CXCR4 is a marker of poor prognosis in various neoplasms, correlating with metastatic disease and decreased survival of patients. We studied CXCR4 involvement in cell migration in vitro and dissemination in vivo. We also evaluated the prognostic significance of CXCR4 in 94 biopsies of DLBCL patients. We observed that the level of expression of CXCR4 in DLBCL cell lines correlated positively with in vitro migration. Expression of the receptor was also associated with increased engraftment and dissemination, and decreased survival time in NOD/SCID mice. Furthermore, administration of a specific CXCR4 antagonist, AMD3100, decreased dissemination of DLBCL cells in a xenograft mouse model. In addition, we found that CXCR4 expression is an independent prognostic factor for shorter overall survival and progression-free survival in DLBCL patients. These results show that CXCR4 mediates dissemination of DLBCL cells and define for the first time its value as an independent prognostic marker in DLBCL patients.

Focal adhesion protein expression in human diffuse large B-cell lymphoma.

AIMS: Focal adhesions have been associated with poor prognosis in multiple cancer types, but their prognostic value in diffuse large B-cell lymphoma (DLBCL) has not been evaluated. The aim of this study was to investigate the expression patterns and the prognostic value of the focal adhesion proteins FAK, Pyk2, p130Cas and HEF1 in DLBCL. METHODS AND RESULTS: Focal adhesion protein expression was examined using immunohistochemistry in normal lymphoid tissues and in 60 DLBCL patient samples. Kaplan-Meier survival and Cox regression analysis were performed to evaluate the correlation of focal adhesion protein expression with patient prognosis. FAK, Pyk2, p130Cas and HEF1 expression was mostly found in the germinal centres of normal human lymphoid tissues. When assessed in DLBCL samples, FAK, Pyk2, p130Cas and HEF1 were highly expressed in 45%, 34%, 42% and 45% of the samples, respectively. Multivariate Cox analysis revealed that decreased FAK expression was a significant independent predictor of poorer disease outcome. CONCLUSIONS: FAK expression is an independent prognostic factor in DLBCL. Our results suggest that the addition of FAK immunostaining to the current immunohistochemical algorithms may facilitate risk stratification of DLBCL patients.

ITS-based detection and quantification of Alternaria spp. in raw and processed vegetables by real-time quantitative PCR.

A TaqMan real-time polymerase chain reaction (PCR) method was developed for specific detection of Alternaria spp. in foodstuffs. The method uses Alternaria-specific primers and probe targeting the internal transcribed spacer regions ITS1 and ITS2 of the rRNA gene, and a positive amplification control based on 18S rRNA gene. The applicability of the real-time PCR protocol was assessed through analysis of 190 commercial food samples, including 80 fresh fruit and vegetable samples and 110 processed foodstuffs. The assay demonstrated the presence of Alternaria spp. DNA in 46 out of the 80 raw samples (57.5%) and in 66 out of the 110 processed samples (60%), enabling quantitative detection of Alternaria spp. DNA at levels as low as 1 CFU/g. The estimated Alternaria counts obtained by real-time PCR showed a good relationship (R(2) = 0.9006, P < 0.01) with the Alternaria counts obtained by plating on Potato Carrot Agar (PCA). The developed real-time PCR assay provides a useful tool for early detection of Alternaria spp. and could be applied as a quality and biosecurity marker of raw materials and final products in the fruits and vegetables processing industries.

Subcutaneous passage increases cell aggressiveness in a xenograft model of diffuse large B cell lymphoma.

Xenograft models of human diffuse large B cell lymphoma (DLBCL) are widely used to test new drugs against this neoplasia. Most of them, however, are subcutaneous xenografts that do not show a disseminated disease as it is found in the human neoplasia. In this paper, we aimed to develop a disseminated xenograft model of DLBCL by performing a subcutaneous passage of DLBCL cells before their intravenous injection in mice. WSU-DLCL-2 (WSU) cells were injected into both flanks of NOD/SCID mice. The subcutaneous tumours were disaggregated and a cell suspension (WSU-SC) was obtained. Two groups of 10 NOD/SCID mice were intravenously injected with WSU-SC or WSU cells. All mice injected with WSU-SC cells developed lymphoma in 32-47 days and showed lymph node and bone marrow infiltration. WSU-SC cells showed a significantly higher engraftment rate and faster dissemination than WSU cells after intravenous injection in mice. When molecularly compared, WSU-SC cells showed higher expression levels of FAK, p130Cas and phosphorylated AKT than WSU cells. The subcutaneous passage enhanced the engraftment and the metastatic capacity of WSU cells, allowing the generation of a rapid and disseminated DLBCL xenograft model. The aggressive behaviour of WSU-SC cells was associated with increased p130Cas and FAK expression and AKT activation.