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Demethylation of the long interspersed nuclear element (LINE-1; L1) antisense promoter can result in transcription of neighboring sequences as for the L1-MET transcript produced by the L1 placed in the second intron of MET. To define the role of L1-MET, we investigated the sequence and the transcription of L1-MET in vitro models and heterogeneous breast cancers, previously reported to show other L1-derived transcripts. L1-MET expressing cell lines were initially identified in silico and investigated for L1-MET promoter methylation, cDNA sequence and cell fraction mRNA. The transcriptional level of L1-MET and MET were then evaluated in breast specimens, including 9 cancer cell lines, 41 carcinomas of different subtypes, and 11 normal tissues. In addition to a L1-MET transcript ending at MET exon 21, six novel L1-MET splice variants were identified. Normal breast tissues were negative for the L1-MET expression, whereas the triple-negative breast cancer (TNBC) and the high-grade carcinomas were enriched with the L1-MET mRNA (p = 0.005 and p = 0.018, respectively). In cancer cells and tissues the L1-MET expression was associated with its promoter hypomethylation (ρ = -0.8 and -0.9, respectively). No correlation was found between L1-MET and MET mRNA although L1-MET expressing tumors with higher L1-MET/MET ratio were negative for the MET protein expression (p = 0.006). Besides providing the first identification and detailed description of L1-MET in breast cancer, we clearly demonstrate that higher levels of this transcript specifically recognize a subset of more aggressive carcinomas, mainly TNBC. We suggest the possible evaluation of L1-MET in the challenging diagnosis of early TNBCs.

Formalin fixation and paraffin embedding (FFPE) represent the standard method to preserve tissue specimens for diagnostic pathology, however formalin fixation induces severe fragmentation of nucleic acids. We investigated whether formalin fixation at 4°C could preserve DNA integrity in FFPE specimens. Paired samples from 38 specimens were formalin fixed at room temperature (stdFFPE) and at 4°C (coldFFPE), respectively. Two independent cohorts were prospectively collected, cohort A (collected 6 years prior to the study, n = 21), cohort B (collected at time of the study, n = 17). DNA was extracted and its integrity evaluated with a qPCR-based assay that produces a normalized integrity index, the QC score (ratio between the quantity of a long and a short amplicon of the same gene). We observed higher QC scores in coldFFPE compared to stdFFPE samples (mean values: 0.69 vs. 0.36, p < 0.0001) and stdFFPE breast cancer specimens showed the most detrimental effect overall. Comparable QC scores were obtained between coldFFPE tissues of both cohorts; conversely, DNA integrity of stdFFPE was significantly lower in cohort A compared to cohort B (p < 0.0001). Of note, QC scores of stdFFPE (but not of coldFFPE) samples were significantly reduced following 6 months of storage (p = 0.0001). Monitored formalin fixation at 4°C outperforms standard fixation in ensuring high-quality DNA, which is key to feasibility of downstream high-throughput molecular analyses. An important effect was observed over storage time, thus suggesting a likely better preservation of archival samples when this cold fixation protocol is used.

Purpose Overexpression of miR-100 in stem cells derived from basal-like breast cancers causes loss of stemness, induction of luminal breast cancer markers and response to endocrine therapy. We, therefore, explored miR-100 as a novel biomarker in patients with luminal breast cancer.Methods miR-100 expression was studied in 90 patients with oestrogen-receptor-positive/human-epidermal growth factor receptor 2-negative breast cancer enrolled in a prospective study of endocrine therapy given either preoperatively, or for the treatment of de novo metastatic disease. Response was defined as a Ki67 ≤2.7% after 21±3 days of treatment. The prognostic role of miR-100 expression was evaluated in the Molecular Taxonomy of Breast Cancer International Consortium (METABRIC) and The Cancer Genome Atlas (TCGA) breast cancer datasets. Additionally, we explored the correlation between miR-100 and the expression its targets reported as being associated with endocrine resistance. Finally, we evaluated whether a signature based on miR-100 and its target genes could predict the luminal A molecular subtype.Results Baseline miR-100 was significantly anticorrelated with baseline and post-treatment Ki67 (p

Receptor tyrosine kinases (RTKs) inhibitors&rsquo, activity in advanced osteosarcoma is significant but short-lived. To prevent or at least delay drug resistance, we explored a vertical inhibition by combining drugs acting at different levels of the RTK pathways (pazopanib + trametinib). We studied pazopanib + trametinib antitumor activity both in vitro and in vivo (MNNG-HOS and KHOS xenografts in NOD/SCID mice) investigating the molecular mechanisms and potential escapes. The involvement of MAPK-PI3K pathways was validated by Nanostring technology, western blot and by silencing/overexpression experiments. Pazopanib targets were expressed on seven osteosarcoma cell lines and their pathways were activated. Pazopanib + trametinib exhibited synergistic antitumor activity by inducing apoptosis and inhibiting ERK1/2 and Akt. In vivo antitumor activity was shown in osteosarcoma-bearing mice. The drug combination significantly down-modulated RTK Ephrin Type-A Receptor 2 (EphA2) and Interleukin-7 Receptor (IL-7R), whereas induced mitogen-activated protein-kinase kinase (MAPKK) MEK6. EphA2 silencing significantly reduced osteosarcoma cell proliferation and migration, while impeding MEK6 up-regulation in the treated cells significantly increased the antitumor effect of the studied drugs. Moreover, the up-regulation of MEK6 reduced combination activity. Pazopanib + trametinib demonstrated synergistic antitumor effects in osteosarcoma models through ERK and Akt inhibition and EphA2 and IL-7R down-modulation. MEK6 up-regulation might evoke escaping mechanism.

Background. In a phase II study for patients with relapsed small cell lung cancer (SCLC), the administration of Temozolomide, an alkylating agent used in gliomas and anaplastic astrocytoma, showed a effective activity when O6-methylguanine-DNA methyltransferase (MGMT) gene promoter was methylated. Methods. We tested the feasibility of MGMT promoter status evaluation in small biopsies and cytological specimens routinely processed for diagnostic purposes. We tested samples from 56 patients with SCLC: 30 tissue biopsies, 17 fine-needle aspiration biopsy, 8 bronchial washing, and 1 was a sputum. Biopsies and fine-needle aspiration biopsy were fixed in formalin, bronchial washing and sputum in Dubosq Brazil. DNA was extracted after macrodissection of the areas containing the maximum number of cancer cells. MGMT promoter methylation status was assessed by methylation specific PCR. Results. Methylation analysis was obtained in 54 samples (54/56) and failed in two bronchial wash. MGMT promoter was methylated in 35.2% of the cases without any significant difference between histological and cytological samples (37.9% vs. 32%). Conclusion. MGMT promoter methylation is present in SCLC and cytological samples are perfectly adequate for methylation analysis, even if they were taken during routine diagnostic procedures, using different fixative and with low number and percentage of cancer cells. Diagn. Cytopathol. 2015;43:947–952. © 2015 Wiley Periodicals, Inc.

The aim of this study was to determine whether detection of β-HPV gene products, as defined in epidermodysplasia verruciformis skin cancer, could also be observed in lesions from kidney transplant recipients alongside the viral DNA. A total of 111 samples, corresponding to 79 skin lesions abscised from 17 kidney transplant recipients, have been analyzed. The initial PCR analysis demonstrated that β-HPV-DNA was highly present in our tumor series (85%). Using a combination of antibodies raised against the E4 and L1 proteins of the β-genotypes, we were able to visualize productive infection in 4 out of 19 actinic keratoses, and in the pathological borders of 1 out of 14 squamous cell carcinomas and 1 out of 31 basal cell carcinomas. Increased expression of the cellular proliferation marker minichromosome maintenance protein 7 (MCM7), that extended into the upper epithelial layers, was a common feature of all the E4-positive areas, indicating that cells were driven into the cell cycle in areas of productive viral infections. Although the present study does not directly demonstrate a causal role of these viruses, the detection of E4 and L1 positivity in actinic keratosis and the adjacent pathological epithelium of skin cancer, clearly shows that β-HPV are actively replicating in the intraepidermal precursor lesions of kidney transplant recipients and can therefore cooperate with other carcinogenic agents, such as UVB, favoring skin cancer promotion.

Mutations of KRAS are detectable in 70–90% of pancreatic duct adenocarcinomas (PDAC), using direct sequencing. We used a highly sensitive molecular method in order to investigate: (a) the frequency and prognostic significance of different KRAS mutations and, (b) whether the presence of KRAS mutations in histologically-negative resection margins of PDAC could explain local tumor recurrence after surgery. Twenty-seven patients with histologic diagnosis of PDAC, radical pancreaticoduodenectomy and histologically-negative margins were evaluated. KRAS mutations were searched for mutant-enriched PCR in tumor and negative resection margins. KRAS mutations were detected in 85.2% of the cases; the most frequent mutation was G12D (48.1%). Shorter OS was found in patients with G12D (25 months; 95% CI, 20.5–29.5), vs patients with other mutations (31.5 months; 95% CI, 25.6–37.1) (N.S.). KRAS mutation in histologically-negative margins was detected in one patient who died of locoregional recurrence; six patients had tumor recurrence but no mutations in surgical margins. The high frequency of KRAS mutations suggests a search for KRAS status to improve the diagnosis in suspected cases; the G12D mutation could be related to poor prognosis, but without statistical significance. No correlation was found between the frequency of cancer recurrence and KRAS mutations in surgical margins.

The activation of the LINE-1 sequence located within the second intron of MET leads to the onset of L1-MET transcript. We recently characterized the full L1-MET structure in breast cancer and showed that high levels of this transcript recognize a subset of more aggressive breast carcinomas, mainly of triple negative phenotype. However, at present, the relationship between L1-MET and MET is still poorly understood. In order to elucidate this function, we silenced L1-MET transcription using cells expressing different levels of L1-MET/MET, including lung cancer (A549 and EBC1), gastric cancer (GTL16), and breast cancer (MDA-MB231), that were transiently transfected with Gapmers-LNA (Exiqon), specifically targeting L1-MET sequence. Cell viability and apoptosis were evaluated after 24 h by cell count, Cell Titer Glow (Promega) and propidium iodide/annexin based-cytofluorimeter assays. RNA was purified from sample and control cells to assess the L1-METsilencing by qRT-PCR and to evaluate the gene-expression of a subset of cancer-related genes using Nanostring Technology, whereas western blot analyses were carried out to measure the protein expressions. A significant decrease of cell viability was detected in A549, EBC1 and GTL16, but not in MDA-MB231 cells, characterized by the lowest level of L1-MET overall. In parallel, the highly expressing L1-MET cells showed an increased rate of early and late apoptosis together with a strong reduction of MET gene and its protein expression. On the contrary, in MDA-MB231 cells L1-MET silencing induced only a slight MET gene and protein impairment. Overall, L1-MET knock-down caused a decrease expression of a conserved gene cluster, including a marked reduction of EGFR protein expression. Moreover, L1-MET silenced cells showed lower MET and EGFR phosphorylation, with a downstream silencing effect on pERK and pAKT. Results of cell treatment with the inhibitors of lysosome and proteasome activity bafilomycin and MG-132 ruled out the interaction of L1-MET silencing with protein degradation pathway. This is the first study investigating the function of the L1-MET transcript in cancer models. Our results show that although L1-MET is unable to encode for a protein, its silencing exerts a strong phenotypic effect on different tumor cell types, suggesting potential regulations at the transcriptional level. Note: This abstract was not presented at the meeting. Citation Format: Enrico Berrino, Umberto Miglio, Valentina Miano, Letizia Lanzetti, Silvia Benvenuti, Carla Debernardi, MIchele De Bortoli, Caterina Marchio, Tiziana Venesio, Anna Sapino. L1-MET transcription silencing modulates MET and EGFR gene and their protein expression and induces apoptosis and cell-death in different types of cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 261.

e22509 Background: Receptor tyrosine kinases (RTKs) and their signal transducers are suitable targets for the treatment of advanced OS. We evaluated the antitumor activity of the RTK inhibitor P and the MEK inhibitor T and deeply investigated molecular mechanisms behind their activity and potential escape. Methods: Flow cytometry and western blot analyses were carried out in 7 OS cell lines to study the expression of RTK P targets and the activation of their pathways, respectively. Cell viability and colony growth were evaluated after 72h and 7-day treatment respectively, with scalar doses of both single agents and their constant combination. Cell cycle distribution and apoptosis were evaluated by flow cytometry after 72h. In vivo antitumor activity was studied in NOD/SCID mice bearing MNNG-HOS xenografts after 3 weeks of treatment. Cell migration was studied by scratch assays. The involvement of MAPK-PI3K pathway key transducers was explored by Vantage 3D RNA Panel and Nanostring technology, validated by western blot and confirmed by silencing experiments. Results: P targets are expressed on OS cell lines and their pathways are activated. P+T have synergistic antitumor activity (combination index < 1) in OS cell lines by inducing apoptosis (6/7) and inhibiting both ERK1/2(7/7) and AKT (7/7). Furthermore, in vivo antitumor activity was shown in OS bearing mice (tumor volume: P+T/untreated = 0.036, p = 0.002). P+T significantly down-modulated RTK EphaA2 (mean log2 fold change RNA P+T/untreated = -2.02±0.50) and induced Janus kinase MEK6 (mean log2 fold change RNA P+T/untreated = 2.9±0.51). EphA2 silencing reduced cellular proliferation and migration of OS cells. Impeding MEK6-up-regulation in P+T treated cells significantly increased the antitumor effect (51.5±14.3%) of the studied drugs. Conclusions: P+T exert antitumor activity in OS preclinical models through ERK and AKT inhibition and EphA2 downmodulation. MEK6-upregulation after P+T is likely implied in escape mechanism.

Merkel cell carcinoma (MCC) is an uncommon neuroendocrine tumour of the skin; rare cases have been reported within the lymph nodes without a primary site. The detection of Merkel cell polyomavirus (MCPyV) DNA, integrated within the genome of MCC, suggests its role for the onset of this tumour. We report a case of MCC in an inguinal lymph node of a patient with Von Willebrand disease (VWD), who underwent multiple blood transfusions following haemorrhoidectomy. The diagnosis was performed on the bases of morphology and immunohistochemistry; genomic sequences of LT and VP1 regions of MCPyV were amplified from MCC using a quantitative polymerase chain reaction (qPCR) assay. High levels of MCPyV antibodies were detected in the patient's serum by ELISA method. We discuss the role of MCPyV in the development of this tumour, the use of viral DNA detection for confirming the diagnosis of MCC in unusual sites and the possibility of MCPyV transmission from blood donors.

Polyomavirus-associated nephropathy (PVAN) is a major complication that occurs after renal transplantation and is induced by reactivation of the human polyomavirus BK (BKV). The structure of the viral capsid protein 1 (VP1) is characterized by the presence of external loops, BC, DE, EF, GH, and HI, which are involved in receptor binding. The pathogenesis of PVAN is not well understood, but viral risk factors are thought to play a crucial role in the onset of this pathology. In an attempt to better understand PVAN pathogenesis, the BKV-VP1 coding region was amplified, cloned, and sequenced from the urine of kidney transplant recipients who did, and did not, develop the pathology. Urine viral loads were determined by using real time quantitative PCR (Q-PCR). Amino acid substitutions were detected in 6/8 patients, and 6/7 controls. The BC and EF loop regions were most frequently affected by mutations, while no mutations were found within the GH and HI loops of both patients and controls. Some mutations, that were exclusively detected in the urine of PVAN patients, overlapped with previously reported mutations, although a correlation between changes in amino acids and the development of PVAN was not found. Urine viral loads were higher than that of the proposed cut-off loads for identification of patients that are at a high risk of developing PVAN (10(7) copies/ml), both in the PVAN and control groups, thus confirming that urine viral load is not a useful predictive marker for the development of PVAN.

The standard of care for malignant pleural mesothelioma (MPM) is a combination of platinum compounds and Pemetrexed. Still, the median survival of MPM patients is low (about 12 months). Excision Repair Cross Complementing Group 1 (ERCC1) acts by removing DNA adducts formed by platinum compounds, whereas Pemetrexed inhibits Thymidylate Synthase (TS), which is involved in DNA synthesis. Pleural biopsies were collected from 140 MPM patients (98 males and 42 females, mean age 68 years) before treatment initiation. Average disease specific survival was 13 months (range 1-60). mRNA was extracted from formalin fixed paraffin blocks, reverse transcribed and assayed by qRT-PCR. Immunohistochemistry with anti-ERCC1 and anti-TS mAbs was scored semi-quantitatively. Of 140 patients, 102 were treated, the remaining were not because of bad performance status or advanced age. Patients with low ERCC1 protein expression survived longer (24.3 vs 12.5 months, P=.03). Likewise, patients with low levels of TS mRNA had better s...

AimsCytokeratin 19 (CK19) mRNA copy number predicts the probability of tumour load in axillary lymph nodes (ALN) and can help in decision-making regarding the axillary dissection. The purpose of this study was to define a new cut-off of CK19 mRNA copy number using the one-step nucleic acid amplification (OSNA) assay on metastatic sentinel lymph nodes (SLN) in order to identify cases at risk of having one or more positive ALN.Methods1296 SLN from 1080 patients were analysed with the OSNA assay. 194 patients with positive SLN underwent ALN dissection and the mean value of CK19 copy number (320 000) of their SLN was set as initial cut-off. Receiver operative characteristics curve identify a best cut-off of 7700 (sensitivity 78%, specificity 57%). A comparison between our and the traditional cut-off (5000) was performed.ResultsThe cut-off of 7700 successfully identifies patients with positive ALN (p=0.001, false- negative cases: 17%). In the range between 5000 and 7700, one patient with positive ALN would not undergo axillary dissection, whereas eight patients with negative ALN would be correctly identified.ConclusionsWe suggest that the level of CK19 mRNA copy number could be the only parameter to consider in the intraoperative management of the axilla.

Background Correlating human papillomavirus (HPV) type with the clinical and histopathological features of skin lesions (from genital and nongenital sites) can present a diagnostic challenge. Objective In this study, HPV infection patterns were correlated with pathology and clinical presentation in lesional and nonlesional body sites from a young patient with a primary T-cell immunodeficiency. Methods HPV infection was evaluated at both DNA and protein levels by polymerase chain reaction and immunohistochemistry. Results The patient's genital lesions were caused exclusively by α-genotypes (high-risk type HPV-51 in the anal and low-risk type HPV-72 in the penile condylomas). The opposite was true for the skin lesions, which were infected by β-genotypes alone (HPV-8 and HPV-24). HPV-24 was the predominant type in terms of viral load, and the only one found in productive areas of infection. The patient had already developed high-grade dysplasia in the anal condyloma-like lesions, and showed areas of early-stage dysplasia in the lesions caused by the β-genotype HPV-24. Limitations The basic origin of the immunodeficiency is not yet defined. Conclusion These findings provide proof of principle that both α- and β-genotypes can cause overt dysplastic lesions when immunosurveillance is lost, which is not restricted to epidermodysplasia verruciformis.

Mutation analysis of KRAS is needed before starting treatment with anti-EGFR monoclonal antibodies in patients with metastatic colorectal cancer (CRC). In most of the cases, testing is performed on primary tumors, assuming that KRAS mutation status does not change in metastasis although correlation studies gave conflicting results. We evaluated the KRAS status concordance rate between primary tumors and related metastasis using a highly sensitive molecular assay. Forty-five primary tumors and related metastases from patients with CRC (28/45 male-62.2% and 17/45 female-37.8%; mean age 66.4 years) were analyzed by using TheraScreen: KRAS mutational kit. Metastatic samples were collected from lymph nodes (8/45-17.8%) and visceral sites (37/45-82.2%); 23 were synchronous (49%) and 22 were metachronous (51%), obtained after a mean of 30.8 months after the first diagnosis of CRC. Twenty-eight patients had KRAS mutations in both primary CRC and related metastases (62.2%). No differences in type and frequency of mutations were identified, despite different metastatic sites and time of onset of metastatic disease. Our results indicate that the mutation status of KRAS is the same in primary CRC and metastasis, suggesting that in clinical practice, KRAS testing can be performed on both tumor tissues when using a highly sensitive molecular assay.

Epidermal growth factor receptor ( EGFR ) gene mutational analysis is critical for guiding the treatment of lung adenocarcinoma. In everyday clinical practice, EGFR testing is frequently centralized in referral laboratories that may receive paucicellular cytologic specimens, often fixed in various ways. We conducted a search for EGFR mutations in 108 cytologic samples of lung adenocarcinoma from different hospitals using the TheraScreen EGFR29 kit. These samples included 80 (74.1%) fine-needle aspirations, 13 (12%) pleural/ascitic fluids, 13 (12%) bronchial washings, and 2 bronchial brushings. The samples were fixed in ethanol (n = 79), Duboscq-Brasil (n = 18) or formalin (n = 10); 1 was unfixed. Ninety-two (85.2%) were amplified, 16 (14.8%) were not. Mutations were detected in 22 (23.9%) of 92 amplified samples, 9 containing less than 200 cancer cells, and 4 with less than 50% cancer cells. DNA was amplified in 12 of 18 Duboscq-Brasil–fixed samples. These findings indicate that cytologic specimens are adequate for EGFR testing when a highly sensitive assay is used, even if they are paucicellular or not optimally fixed.

Mosquitoes collected in northern Italy were screened for flavivirus RNA. Positive amplicons were sequenced and found most similar to insect flavivirus (ISF), Usutu virus (USUV) and surprisingly also to Japanese encephalitis virus (JEV). The sequence (167 bp), obtained from one pool of Culex pipiens, was found identical to JEV strains from bats in China. Unfortunately additional sequence data or virus isolations were not obtained in this study. Confirmation of potential introduction of JEV to Italy and other European countries is urgently needed.

To assess the sensitivity, specificity, positive and negative predictive values of fluorescence in situ hybridisation (FISH) and conventional cytology in identifying bile duct stricture malignancies.Brushing samples were collected from 64 patients by means of endoscopic retrograde cholangiopancreatography, and assessed cytologically and by means of a multi-probe FISH set. The cytological diagnoses were: positive, negative and suspicious, whereas criteria for FISH positivity were: more than five polysomic cells or more than 10 trisomic cells for chromosomes 3 or 7.Forty-eight of the 64 patients showed histological or clinical signs of malignancy. The sensitivity of cytology was high (77%) if suspicious cases were considered positive, but was significantly lower than that of FISH if suspicious cases were considered negative (58% versus 90%; p0.05). The specificity of cytology was 81% (positive and suspicious) or 100% (negative and suspicious), and the specificity of FISH was 94% (p = 1). FISH yielded one false negative result (isolated chromosome 7 trisomy). FISH allowed a definite diagnosis of 9/12 cytologically inconclusive cases.Our findings suggest using FISH in the case of bile duct strictures cytologically negative or inconclusive; a FISH diagnosis of malignancy should only be made in the presence of polysomic pattern.

Vertical transmission of JC virus and BK virus has been investigated by few authors, with conflicting results. We performed a combined serological and genomic study of 19 unselected pregnant women and their newborns. Blood and urine samples were collected during each gestational trimester from the pregnant women. Umbilical cord blood, peripheral blood, urine and nasopharyngeal secretion samples were taken from newborns at delivery and after 1 week and 1 month of life. Polyomavirus DNA was detected by nested PCR. Polyomavirus IgG-, IgM- and IgA-specific antibodies were measured in maternal and newborn serum samples using a virus-like-particle-based ELISA method. BKV and JCV DNA were detected in urine from 4 (21 %) and 5 (26 %) women, respectively. BKV and JCV seroprevalences in the pregnant women were 84 % and 42 %, respectively. Using a rise in the IgG level or the transient appearance of an IgA or IgM response as evidence of infection in the newborn, we detected BKV and JCV infections in four (21 %) and three (16 %) newborns, respectively. Three infants had serological evidence of infection with both BKV and JCV. In two of the four possible BKV-infected newborns, the mothers seroconverted during pregnancy, while another mother was viruric and IgA seropositive. The mother of one of the three possible JCV-infected newborns was viruric and IgA seropositive; another mother was viruric. These results suggest JC virus and BK virus can be transmitted from mother to newborn during pregnancy or soon after birth.

Given the conflicting results of the few published studies, the aim of this retrospective molecular-based study of 10 aborted fetuses that underwent complete autopsy and 10 placentas was carried out to determine whether BK polyomavirus (BKV) can be transmitted transplacentally. The interruption of pregnancy was due to a miscarriage (five cases) or a prenatal diagnosis of severe intrauterine malformations (five cases). Samples from the brain, heart, lung, thymus, liver, and kidney were taken from each fetus, and two samples were obtained from all of the placentas. The presence of BKV was investigated by means of PCR using primers specific for the transcription control region (TCR) and viral capsidic protein 1 (VP1) and DNA extracted from formalin-fixed, paraffin-embedded tissue. BKV genome was detected in 22 of 60 samples (36.6%) from seven fetuses (70%), regardless of the cause of abortion: VP1 was amplified in 12 samples (54%), TCR in seven (32%), and both in three (14%). VP1 was also detected in one placental sample. BKV sequences were most frequently detected in heart and lung (five cases), but sequence analyses of TCR and VP1 revealed a high degree of genomic variability among the samples taken from different organs and the placenta. These results indicate that BKV can cross the placenta during pregnancy and become latent in fetal organs other than the kidney and brain (previously considered the main targets of BKV latency). This may happen in early pregnancy and does not seem to be associated with an increased risk of abortion.

International audience; Haemorrhagic cystitis is characterized by haematuria due to inflammation of the bladder. In bone marrow transplants, this disease is linked to the infection by human polyomavirus BK, whereas the role of the human polyomavirus JC is unclear. The transcriptional control regions of both viruses contain important cellular transcription factor binding sites that undergo rearrangement process generating suitable variants that could be more active for viral replication and for the onset of haemorrhagic cystitis. In this study urine obtained from seven patients with bone marrow transplant were examined. Polyomavirus genomes were quantified by PCR and viral loads were compared. The transcriptional regions of both viruses were amplified and sequenced to determine the presence of variants. Subtypes of polyomaviruses were determined by amplification and sequencing of the viral protein 1 region. The results showed that 4 of 7 patients were positive for BK DNA, 2 of 7 patients had BK and JC DNA and 1 of 7 had JC DNA. Positive samples were amplified and sequenced successively for transcriptional regions. The viral archetype was always found in both viruses. Finally, typing showed that BK virus subtype I infected patients with BK, whereas JC virus genotype IA and genotype 1B were found in patients infected with JC. The data suggest that new and different approaches are required to improve the morbidity and mortality caused by polyoma-associated haemorrhagic cystitis, since it known that BK virus is involved in the onset of haemorrhagic cystitis, whereas the role of JC virus should be investigated further.

Genomic variability in the viral protein 1 region of BK polyomavirus (BKV) may change the ability of the virus to replicate. The significance of such changes was studied in clinical samples taken from kidney transplant patients with and without BKV nephropathy. A 94 base-pair fragment of viral protein 1 was amplified from 68 urine, 28 blood, and 12 renal biopsy samples from eight patients with BKV nephropathy, and from 100 urine samples, 17 blood and three renal biopsy samples from 41 of 218 controls. The DNA was sequenced and the amino acid changes were predicted by the Expert Protein Analysis System program (ExPASy, Swiss Institute of Bioinformatics, Geneva, Switzerland). Single base-pair mutations were detected more frequently in the samples from the BKV nephropathy patients than in the controls, and this was the only statistically significant finding of the study (P < 0.05), thus suggesting a greater genetic instability in BKV nephropathy associated strains. The amino acid changes were distributed at random in both BKV nephropathy patients and controls. However, one aspartic acid-to-asparagine substitution at residue 75 was detected in all samples of the one patient with BKV-associated nephropathy, who developed disease progression confirmed by histology, and not in any of the other patient or control samples. Whether this specific amino acid change plays a role in disease deserves further study.

Clinical diagnosis of kidney transplants related illnesses is not a simple task. Several studies were conducted to define diseases and complications after renal transplantation, but there are no comprehensive guidelines about diagnostic tools for their prevention and detection. The Authors of this review looked for the medical literature and pertinent publications in particular to understand the role of Human Polyomavirus BK (BKV) in renal failure and to recognize analytical techniques for BK virus associated nephropathy (BKVAN) detection.