Overview of Tumor Heterogeneity in High-Grade Serous Ovarian Cancers

Ovarian cancers encompass a group of neoplasms originating from germinal tissues and exhibiting distinct clinical, pathological, and molecular features. Among these, epithelial ovarian cancers (EOCs) are the most prevalent, comprising five distinct tumor histotypes. Notably, high-grade serous ovarian cancers (HGSOCs) represent the majority, accounting for over 70% of EOC cases. Due to their silent and asymptomatic behavior, HGSOCs are generally diagnosed in advanced stages with an evolved and complex genomic state, characterized by high intratumor heterogeneity (ITH) due to chromosomal instability that distinguishes HGSOCs. Histologically, these cancers exhibit significant morphological diversity both within and between tumors. The histologic patterns associated with solid, endometrioid, and transitional (SET) and classic subtypes of HGSOCs offer prognostic insights and may indicate specific molecular profiles. The evolution of HGSOC from primary to metastasis is typically characterized by clonal ITH, involving shared or divergent mutations in neoplastic sub-clones within primary and metastatic sites. Disease progression and therapy resistance are also influenced by non-clonal ITH, related to interactions with the tumor microenvironment and further genomic changes. Notably, significant alterations occur in nonmalignant cells, including cancer-associated fibroblast and immune cells, during tumor progression. This review provides an overview of the complex nature of HGSOC, encompassing its various aspects of intratumor heterogeneity, histological patterns, and its dynamic evolution during progression and therapy resistance.

Impact of standardization in tissue processing: the performance of different fixatives

Most tissues in clinical practice are formalin-fixed and paraffin-embedded for histological as well as molecular analyses. The reproducibility and uniformity of molecular analyses is strictly dependent on the quality of the biomolecules, which is highly influenced by pre-analytical processes. In this study, the effect of different fixatives was compared, including formalin, Bouin's solution, RCL2® and TAG-1™ fixatives, by stringent application of ISO standards in mouse liver tissue processing, including formalin-free transport of tissues and tissue grossing in a refrigerated environment. The effect of fixatives was studied in terms of nucleic acid quality at the time of tissue processing and after one year of tissue storage at room temperature in the dark. Furthermore, a microcomputed tomography (CT) scan analysis was applied to investigate the paraffin embedding. The results show that the application of ISO standards in tissue processing allows analysis of 400 bases amplicons from RNA and 1000 bases from DNA, even in extracts from formalin-fixed and paraffin-embedded tissues. However, after one year storage at room temperature in the dark, a degradation of the nucleic acids was observed. Nevertheless, extracts can still be analyzed, but for metachronous tests it is highly recommended to repeat the quantitation of housekeeping genes in order to standardize the extent of nucleic acid degradation.

AKT Isoforms Interplay in High-Grade Serous Ovarian Cancer Prognosis and Characterization

Simple Summary

New therapeutical strategies are needed to improve survival in high-grade serous ovarian cancer (HGSOC) patients. AKT inhibitors are promising agents able to act in synergy with PARP inhibitors and platinum-based therapies, but the subset of patients who could benefit from this approach is still unclear. We analyzed AKT isoforms expression in a retrospective cohort and we identified four AKT expression groups related to patients’ survival, tumor morphology and the BRCA status that could help in stratifying patients for future clinical trials.

Abstract

High-grade serous ovarian cancer (HGSOC) is among the deadliest gynecological malignancies. The acquired resistance to platinum-based therapies and the intrinsic heterogeneity of the disease contribute to the low survival rate. To improve patients’ outcomes, new combinatorial approaches able to target different tumor vulnerabilities and enhance the efficacy of the current therapies are required. AKT inhibitors are promising antineoplastic agents able to act in synergy with PARP inhibitors, but the spectrum of patients who can benefit from this combination is unclear, since the role of the three different isoforms of AKT is still unknown. Here, we study the expression of AKT isoforms on a retrospective cohort of archive tissue by RT-droplet digital PCR (ddPCR) analyzing their association with the clinicopathological features of patients. Based on AKT1/AKT2 and AKT1/AKT3 ratios, we define four AKT classes which were related to patients’ survival, tumor morphology and BRCA1 expression. Moreover, our results show that high AKT3 expression levels were frequently associated with tumors having classic features, a low number of mitoses and the presence of psammoma bodies. Overall, our study obtains new insights on AKT isoforms and their associations with the clinicopathological features of HGSOC patients. These evidences could help to better define the subsets of patients who can benefit from AKT and PARP inhibitors therapy in future clinical trials.

Histological patterns and intra-tumor heterogeneity as prognostication tools in high grade serous ovarian cancers

OBJECTIVE

High grade serous ovarian carcinoma (HGSOC) is the most common type of malignant ovarian neoplasm and the main cause of ovarian cancer related deaths worldwide. Although novel biomarkers such as homologous recombination deficiency testing have been implemented into the clinical decision-making algorithm since diagnosis, morphological classification and immunohistochemistry analysis are essential for diagnostic purpose. This study aims at identifying histologic and clinical features that can be predictive of patients' prognosis.

METHODS

Morphological and architectural characterization including SET (Solid-Endometroid-Transitional)/Classic features was carried out in a cohort of 234 patients analyzing 695 slides. From each slide tumor infiltrating lymphocyte (TILs), the presence of necrosis, the number of mitoses, the presence of psammoma bodies, giant cells and atypical mitoses were recorded. Morphological heterogeneity was quantified by the Shannon's diversity index (SDI) considering the percentage of each architectural pattern per patient's slide.

RESULTS

The frequency of architectural patterns and morphological variables varied with respect of the surgical strategy (primary debulking surgery vs interval surgery after neoadjuvant chemotherapy). HGSOCs exhibiting SET features had a longer overall as well as progression free survival. Among SET features, pseudo-endometrioid and transitional like patterns had the best outcome, while it was heterogenous for solid pattern, that had better outcome for BRCA 1 negative and less heterogeneous tumors. In patients submitted to neoadjuvant chemotherapy a higher intratumor heterogeneity as defined by SDI was a negative independent prognostic factor.

CONCLUSIONS

A comprehensive histological examination considering architectural patterns and their heterogeneity can help in prognostication of HGSOCs.

Real-World Data on NGS Diagnostics: a survey from the Italian Society of Pathology (SIAPeC) NGS Network

Next Generation Sequencing (NGS) is increasingly used in diagnostic centers for the assessment of genomic alterations to select patients for precision oncology. The Italian Society of Anatomic Pathology and Diagnostic Cytopathology (SIAPEC) through the Molecular Pathology and Predictive Medicine Study Group (PMMP) has been following the progressive development of centers that have adopted NGS technology in diagnostics over time. In July 2017, a study network on massive parallel sequencing was activated in Italy and recognized as the NGS SIAPeC National Network by the SIAPeC Scientific Society Board. Since then, activities have been implemented within the network that provide for alignment of laboratories through diagnostic concordance analysis and monitoring of centers adhering to the Network. Recently, considering the growing need for extended genomic analyses, the PMMP distributed a national survey to assess activities related to the use of genomic diagnostics in oncology within the NGS SIAPEC National Network.

Thirty centers participated in the survey. Eighty percent of the centers are laboratories within Pathology Departments. The distribution of laboratories in the country, the diagnostic laboratory/population ratio, the staff dedicated, the type and number of sequencing and mechatronics platforms available, the genomic panels utilized, and the type and number of diagnostic tests carried out in the last year in each center, are reported.

The centers were also asked whether they participated in a multidisciplinary Molecular Tumor Board (MTB) for management of patients. Thirty percent of the centers had a MTB that was ratified by regional decree. The professionals most frequently involved in the core team of the MTB are the pathologist, oncologist, molecular biologist, geneticist, pharmacologist, and bioinformatician.

The data from this survey indicate that NGS diagnostics in Italy is still heterogeneous in terms of geographical distribution and the characteristics of laboratories and diagnostic test performed. The implementation of activities that favors harmonization, the logistics and the convergence of biological material in reference centers for molecular analyses is a priority for the development of a functional laboratory network.

A Novel HPLC-Based Method to Investigate on RNA after Fixation

RNA isolated from fixed and paraffin-embedded tissues is widely used in biomedical research and molecular pathology for diagnosis. In the present study, we have set-up a method based on high performance liquid chromatography (HPLC) to investigate the effects of different fixatives on RNA. By the application of the presented method, which is based on the Nuclease S1 enzymatic digestion of RNA extracts followed by a HPLC analysis, it is possible to quantify the unmodified nucleotide monophosphates (NMPs) in the mixture and recognize their hydroxymethyl derivatives as well as other un-canonical RNA moieties. The results obtained from a set of mouse livers fixed/embedded with different protocols as well from a set of clinical samples aged 0 to 30 years-old show that alcohol-based fixatives do not induce chemical modification of the nucleic acid under ISO standard recommendations and confirm that pre-analytical conditions play a major role in RNA preservation.

The Association of Residential Altitude on the Molecular Profile and Survival of Melanoma: Results of an Interreg Study

Cutaneous melanoma (CM) incidence is rising worldwide and is the primary cause of death from skin disease in the Western world. Personal risk factors linked to environmental ultraviolet radiation (UVR) are well-known etiological factors contributing to its development. Nevertheless, UVR can contribute to the development of CM in different patterns and to varying degrees. The present study aimed at investigating whether altitude of residence can contribute to the development of specific types of CM and/or influence its progression. To this aim, 306 formalin-fixed and paraffin-embedded (FFPE) tissues from primary CM diagnosed in different geographical areas were submitted to B-RAF proto-oncogene serine/threonine kinase (BRAF) and N-RAS proto-oncogene GTPase (NRAS) mutational status detection and mRNA and miRNA profiling by qPCR. Genes were chosen for their functions in specific processes, such as immune response (CD2, PDL1, or CD274) and pigmentation (MITF, TYRP1, and TRPM1). Furthermore, four microRNAs, namely miR-150-5p, miR-155-5p, miR-204-5p, and miR-211-5p, were included in the profiling. Our results highlight differences in the gene expression profile of primary CM with respect to the geographical area and the altitude of residence. Melanoma-specific survival was influenced by the gene expression of mRNA and miRNAs and varied with the altitude of patients' residence. In detail, TYRP1 and miR-204-5p were highly expressed in patients living at higher altitudes, unlike miR-150-5p, miR-155-5p, and miR-211-5p. Since miRNAs are highly regulated by reactive oxygen species, it is possible that different regulatory mechanisms characterize CMs at different altitudes due to the different environment and UVR intensity.

The leading role of pathology in assessing the somatic molecular alterations of cancer: Position Paper of the European Society of Pathology

Molecular pathology is an essential part of pathology complementing conventional morphological tools to obtain a correct integrated diagnosis with appropriate assessment of prognosis and prediction of response to therapy, particularly in cancer. There is a concern about the situation of molecular pathology in some areas of Europe, namely, regarding the central role of pathologists in assessing somatic genomic alterations in cancer. In some countries, there are attempts that other laboratory medicine specialists perform the molecular analysis of somatic alterations in cancer, particularly now when next generation sequencing (NGS) is incorporated into clinical practice. In this scenario, pathologists may play just the role of “tissue providers,” and other specialists may take the lead in molecular analysis. Geneticists and laboratory medicine specialists have all background and skills to perform genetic analysis of germline alterations in hereditary disorders, including familial forms of cancers. However, interpretation of somatic alterations of cancer belongs to the specific scientific domain of pathology. Pathologists are necessary to guarantee the quality of the results, for several reasons: (1) The identified molecular alterations should be interpreted in the appropriate morphologic context, since most of them are context-specific; (2) pre-analytical issues must be taken into consideration; (3) it is crucial to check the proportion of tumor cells in the sample subjected to analysis and presence of inflammatory infiltrate and necrosis should be monitored; and 4) the role of pathologists is crucial to select the most appropriate methods and to control the turnaround time in which the molecular results are delivered in the context of an integrated diagnosis. Obviously, there is the possibility of having core facilities for NGS in a hospital to perform the sequence analysis that are open to other specialties (microbiologists, geneticists), but also in this scenario, pathologists should have the lead in assessing somatic alterations of cancer. In this article, we emphasize the importance of interpreting somatic molecular alterations of the tumors in the context of morphology. In this Position Paper of the European Society of Pathology, we strongly support a central role of pathology departments in the process of analysis and interpretation of somatic molecular alterations in cancer.

Reliability of miRNA Analysis from Fixed and Paraffin-Embedded Tissues

In clinical practice, patients’ tissues are fixed and paraffin-embedded in order to enable histological diagnosis. Nowadays, those tissues are also used for molecular characterization. Formalin is the most used fixative worldwide, and Bouin’s solution in some worldwide institutions. Among molecular targets, micro RNAs (miRNAs), the single-stranded non-coding RNAs comprised of 18 to 24 nucleotides, have been demonstrated to be resistant to fixation and paraffin-embedding processes, with consequent possible application in clinical practice. In the present study, let-7e-5p, miR-423-3p, miR-92a-1-5p, miR-30d-5p, miR-155-5p, miR-200a-3p, and miR-429 were investigated in formalin and matched Bouin’s solution-fixed tissues of high grade serous ovarian cancers by means of real-time and droplet digital PCR (ddPCR). Micro RNAs were detectable and analyzable in both formalin- and Bouin’s-fixed specimens, but on average, higher Ct values and lower copies/µL were found in Bouin’s-fixed samples. Data from formalin-fixed samples correlated significantly for most targets with Bouin’s ones, except for let-7e-5p and miR-155-5p. This study shows that miRNAs are analyzable in both formalin- and Bouin’s-fixed specimens, with the possibility, after proper data normalization, to compare miRNA-based data from formalin-fixed samples to those of Bouin’s-fixed ones.

Recent advancements in the study of breast cancer exosomes as mediators of intratumoral communication

Breast cancer is a heterogeneous disease, with a morbidity rate of 27.8% and a mortality rate of 15% among women population worldwide. Understanding how this cancer develops and the mechanisms behind tumor progression and chemoresistance is of utmost importance. Exosomes mediate communication in a population of heterogeneous tumoral cells. They have a cargo composed of oncogenes and oncomiRs which change the transcriptomic scenario of their targeted cells and activate numerous tumor-promoting signaling pathways. Exosomes secreted by breast cancer cells lead to enhanced cell proliferation, replicative immortality, angiogenesis, invasion, migration, and chemoresistance. Studying exosomes from this perspective offers more in depth understanding of breast malignancy and may aid in the future development of early diagnostic, prognostic and therapeutic options. We present the latest findings in this area and offer practical solutions which may further stimulate the much-needed research of exosome in breast cancer.

Overview on Clinical Relevance of Intra-Tumor Heterogeneity

Today, clinical evaluation of tumor heterogeneity is an emergent issue to improve clinical oncology. In particular, intra-tumor heterogeneity (ITH) is closely related to cancer progression, resistance to therapy, and recurrences. It is interconnected with complex molecular mechanisms including spatial and temporal phenomena, which are often peculiar for every single patient. This review tries to describe all the types of ITH including morphohistological ITH, and at the molecular level clonal ITH derived from genomic instability and nonclonal ITH derived from microenvironment interaction. It is important to consider the different types of ITH as a whole for any patient to investigate on cancer progression, prognosis, and treatment opportunities. From a practical point of view, analytical methods that are widely accessible today, or will be in the near future, are evaluated to investigate the complex pattern of ITH in a reproducible way for a clinical application.

Reduced expression of α-L-Fucosidase-1 (FUCA-1) predicts recurrence and shorter cancer specific survival in luminal B LN+ breast cancer patients

Background

The lysosomal enzyme α-L-Fucosidase-1 (FUCA-1) catalyzes the hydrolytic cleavage of terminal fucose residues. FUCA-1 gene is down-regulated in highly aggressive and metastatic human tumors as its inactivation perturbs the fucosylation of proteins involved in cell adhesion, migration and metastases.

Results

Negativity to FUCA-1 was significantly related to the development of later recurrences in breast cancer patients with lymph node involvement at diagnosis. Cancer specific survival of luminal B LN+ patients was influenced by FUCA-1 expression as luminal B LN+ patients with positive expression had a longer cancer specific survival. FUCA-1 mRNA expression was inversely related to cancer stage and lymph node involvement. WB and qPCR analysis of FUCA-1 expression in breast cancer-derived cell lines confirmed an inverse relationship with tumor aggressiveness.

Conclusions

This study shows that, within LN+ breast cancer patients, FUCA-1 is able to identify a sub-set of non recurrent patients characterized by the positive expression of FUCA-1 and that, within luminal B LN+ patients, the expression of FUCA-1 predicts longer cancer specific survival.

Methods

We have analyzed FUCA-1 in 305 breast cancer patients by Immunohistochemistry (IHC), and by qPCR in breast cancer patients and in breast cancer cell lines.

Metformin and aspirin treatment could lead to an improved survival rate for Type 2 diabetic patients with stage II and III colorectal adenocarcinoma relative to non-diabetic patients

Metformin, the drug of choice in the treatment of type 2 diabetes mellitus (DM2), in addition to aspirin (ASA), the drug prescribed for cardioprotection of diabetic and non-diabetic patients, have an inhibitory effect on cancer cell survival. The present population-based study conducted in the province of Trieste (Italy), aimed to investigate the prevalence of DM2 in patients with colorectal adenocarcinoma (CRC) and survival for CRC in diabetic and nondiabetic patients. All permanent residents diagnosed with a CRC between 2004 and 2007 were ascertained through the regional health information system. CRC-specific and relative survival probabilities were computed for each group of patients defined by CRC stage, presence or absence of DM2 treated with metformin, and presence or absence of daily ASA therapy. A total of 515 CRC patients without DM2 and 156 with DM2 treated with metformin were enrolled in the study. At the time of CRC diagnosis, 71 (14%) nondiabetic and 39 (25%) diabetic patients were taking ASA daily. The five-year relative survival for stage III CRC was 101% [95% confidence interval (CI)=76-126] in the 18 patients with DM2 treated with metformin and ASA, 55% (95% CI=31-78) in the 23 without DM2 treated with ASA, 55% (95% CI=45-65) in the 150 without DM2 not taking ASA, and 29% (95% CI=13-45) in the 43 with DM2 treated with metformin, however not with ASA. The findings support the hypothesis of a possible inhibitory effect of metformin and ASA on CRC cells. Randomized controlled trials are required to verify this hypothesis.

Liquid dynamic medicine and N-of-1 clinical trials: a change of perspective in oncology research

The increasing use of genomics to define the pattern of actionable mutations and to test and validate new therapies for individual cancer patients, and the growing application of liquid biopsy to dynamically track tumor evolution and to adapt molecularly targeted therapy according to the emergence of tumor clonal variants is shaping modern medical oncology., In order to better describe this new therapeutic paradigm we propose the term "Liquid dynamic medicine" in the place of "Personalized or Precision medicine". Clinical validation of the "Liquid dynamic medicine" approach is best captured by N-of-1 trials where each patient acts as tester and control of truly personalized therapies.

A Practical Approach to Tumor Heterogeneity in Clinical Research and Diagnostics

This Pathobiology issue tries to better define the complex phenomenon of intratumor heterogeneity (ITH), mostly from a practical point of view. This topic has been chosen because ITH is a central issue in tumor development and has to be investigated directly in patient tissue and immediately applied in the treatment of the presenting patient. Different types of ITH should be considered: clonal genetic and epigenetic evolution, morphological heterogeneity, and tumor sampling, heterogeneity resulting from microenvironmental autocrine and paracrine interaction, and stochastic plasticity related to different functional cell efficiencies. For a higher level of reproducibility in clinical research and diagnostics, it is necessary to establish standardized analytical methods, including microdissection. In situ techniques can be pivotal to explore tumor microenvironment and can be improved with associated digital analysis. Liquid biopsies for plasma DNA analysis are at present the best method to study recurrent tumors with treatment adaptation, and widespread clinical use could be beneficial. The different types of tumor genomic instabilities could have pragmatic applications to rank ITH for clinical applications: treatment approaches differ in patients with a high nucleotide mutation rate and patients with high copy number alterations.

A novel oncogenic BTK isoform is overexpressed in colon cancers and required for RAS-mediated transformation

Bruton's tyrosine kinase (BTK) is essential for B-cell proliferation/differentiation and it is generally believed that its expression and function are limited to bone marrow-derived cells. Here, we report the identification and characterization of p65BTK, a novel isoform abundantly expressed in colon carcinoma cell lines and tumour tissue samples. p65BTK protein is expressed, through heterogeneous nuclear ribonucleoprotein K (hnRNPK)-dependent and internal ribosome entry site-driven translation, from a transcript containing an alternative first exon in the 5'-untranslated region, and is post-transcriptionally regulated, via hnRNPK, by the mitogen-activated protein kinase (MAPK) pathway. p65BTK is endowed with strong transforming activity that depends on active signal-regulated protein kinases-1/2 (ERK1/2) and its inhibition abolishes RAS transforming activity. Accordingly, p65BTK overexpression in colon cancer tissues correlates with ERK1/2 activation. Moreover, p65BTK inhibition affects growth and survival of colon cancer cells. Our data reveal that BTK, via p65BTK expression, is a novel and powerful oncogene acting downstream of the RAS/MAPK pathway and suggest that its targeting may be a promising therapeutic approach.

The proliferation marker Ki67, but not neuroendocrine expression, is an independent factor in the prediction of prognosis of primary prostate cancer patients

Background

Neuroendocrine markers, which could indicate for aggressive variants of prostate cancer and Ki67 (a well-known marker in oncology for defining tumor proliferation), have already been associated with clinical outcome in prostate cancer. The aim of this study was to investigate the prognostic value of those markers in primary prostate cancer patients.

Patients and methods

NSE (neuron specific enolase), ChrA (chromogranin A), Syp (Synaptophysin) and Ki67 staining were performed by immunohistochemistry. Then, the prognostic impact of their expression on overall survival was investigated in 166 primary prostate cancer patients by univariate and multivariate analyses.

Results

NSE, ChrA, Syp and Ki67 were positive in 50, 45, 54 and 146 out of 166 patients, respectively. In Kaplan-Meier analysis only diffuse NSE staining (negative vs diffuse, p = 0.004) and Ki67 (≤ 10% vs > 10%, p < 0.0001) were significantly associated with overall survival. Ki67 expression, but not NSE, resulted as an independent prognostic factor for overall survival in multivariate analysis.

Conclusions

A prognostic model incorporating Ki67 expression with clinical-pathological covariates could provide additional prognostic information. Ki67 may thus improve prediction of prostate cancer outcome based on standard clinical-pathological parameters improving prognosis and management of prostate cancer patients.

Expression of the Endocannabinoid Receptor 1 in Human Stroke: An Autoptic Study

OBJECTIVE

Stroke is one of the leading causes of disability and death in the world. The endocannabinoid (eCB) system is upregulated in several neurological diseases including stroke. A previous animal study demonstrated an increased expression of the endocannabinoid receptor 1 (CB1R) in the penumbra area surrounding the ischemic core, suggesting a crucial role in inflammation/reperfusion after stroke. Regarding the localization of CB1/CB2 receptors, animal studies showed that cortical neurons, activated microglia, and astroglia are involved. Our aim was to evaluate the cerebral expression of CB1R in the ischemic brain areas of 9 patients who died due to acute cerebral infarction in the middle cerebral artery territory.

METHODS

The cerebral autoptic tissue was collected within 48 hours since death. Ischemic and contralateral normal-appearing areas were identified. After tissue preprocessing, 4-µm-thick cerebral sections were incubated with the primary CB1R antibodies (Cayman Chemical Company, Ann Arbor, MI). Thereafter, all cerebral sections were hematoxylin treated. In each section, the total cell number and CB1R-positive cells were counted and the CB1R-positive cell count ratio was calculated. For statistical analysis, Student's t-test was used.

RESULTS

In normal tissue, CB1R-positive neurons were the majority; a few non-neuronal cells expressed CB1R. In the ischemic areas, a few neurons were detectable. A significant increase in total CB1R staining was found in the ischemic regions compared to contralateral areas.

CONCLUSIONS

We found an increase in CB1R expression in the ischemic region (neuronal and non-neuronal cell staining), suggesting the inflammatory reaction to the ischemic insult. Whether such response might mediate neuroprotective actions or excitotoxicity-related detrimental effects is still unclear.

Abstract B121: A novel oncogenic BTK isoform is overexpressed in colon cancers and required for RAS-mediated transformation

It is known that Bruton's tyrosine kinase (BTK) is essential for B-cell proliferation/differentiation and it is generally believed that its expression and function are limited to bone marrow-derived cells. Here, we report the identification and characterization of p65BTK, a novel oncogenic isoform expressed in colon carcinomas.

Standard procedures were used for cloning the full length p65BTK-encoding mRNA and raise anti-p65BTK specific polyclonal antibodies. Quantitative PCR, western blot, RNA immunoprecipitation, silencing experiments and fluorescence assay upon transfection with bi-cistronic vectors were used to demonstrate post-transcriptional regulation of p65BTK expression. Immunohystochemistry was employed to study p65BTK expression in colon cancer patients specimens. Soft agar assay and foci assay were carried out to assess p65BTK oncogenic properties. Cell growth, cell viability and colony assays were performed to study the effects of p65BTK inhibition (by a specific kinase inhibitor) on colon cancer cells biology.

We found that p65BTK differs from the already known 77 kDa isoform for the lack of the N-terminal PH domain and is translated - through an IRES-dependent mechanism -from a transcript containing an alternative first exon in the 5'UTR. Moreover, p65BTK mRNA translation requires phosho-hnRNPK binding to its cognate sites (located in the alternative first exon) and is post-transcriptionally regulated, via hnRNPK, by the MAPK pathway. We demonstrate that p65BTK is endowed with strong transforming activity that depends on active ERK1/2 and its inhibition abolishes RAS transforming activity. Accordingly, p65BTK overexpression in colon cancer tissues correlates with ERK1/2 activation. Finally we show that p65BTK inhibition affects growth and survival of colon cancer cells.

In conclusion, our data reveal that BTK, via p65BTK expression, is a novel and powerful oncogene acting downstream of the RAS/MAPK pathway and suggest that its targeting may be a promising therapeutic approach.

Citation Format: Emanuela Grassilli, Fabio Pisano, Annamaria Cialdella, Sara Bonomo, Carola Missaglia, Maria Grazia Cerrito, Laura Masiero, Leonarda Ianzano, Robert Narloch, Filomena D'Amato, Barbara Noli, Gian Luca Ferri, Biagio E. Leone, Giorgio Stanta, Serena Bonin, Kristian Helin, Roberto Giovannoni, Marialuisa Lavitrano. A novel oncogenic BTK isoform is overexpressed in colon cancers and required for RAS-mediated transformation. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr B121.

In stage II/III lymph node-positive breast cancer patients less than 55 years of age, keratin 8 expression in lymph node metastases but not in the primary tumour is an indicator of better survival

Axillary lymph node status is one of the most important prognostic variables for breast cancer (BC). To investigate and understand the clinical, histopathological and biological factors that affect prognosis in node-positive young breast cancer patients, we compared the phenotype of 100 primary tumours with their corresponding loco-regional lymph node (LN) metastases using conventional immunohistochemistry (IHC) markers currently in use for molecular classification of breast cancer. By comparing the expression of ER, PR, HER-2, Ki67, K8, K5/6 and vimentin, we found that expression of HER-2, Ki67, K8 and vimentin is frequently lost in lymph node metastases. Between the primary tumour and corresponding lymph node metastases, expression of keratins K8 and K5/6 significantly changed. Expression of K8 in lymph node metastases, but not in primary tumours, segregates patients in two sub-groups with different outcomes. Survival of patients with K8-positive LN metastases at 5 years in comparison with patients with K8-negative LN metastases was 75 vs 48 %, at 10 years 62 vs 22 % and at 20 years 53 vs 14 % (p < 0.001). K8 immunostaining of tissue from the lymph node metastasis allows defining a sub-group of lymph node-positive BC patients with a highly unfavourable outcome, for whom therapeutic options might have to be reconsidered.

Report from the OECI Oncology Days 2014

The 2014 OECI Oncology Days was held at the 'Prof. Dr. Ion Chiricuta' Oncology Institute in Cluj, Romania, from 12 to 13 June. The focus of this year's gathering was on developments in personalised medicine and other treatment advances which have made the cost of cancer care too high for many regions throughout Europe.

Models of biobanking and tissue preservation: RNA quality in archival samples in pathology laboratories and "in vivo biobanking" by tumor xenografts in nude mice-two models of quality assurance in pathology

Tissue banks represent essential resources and platforms for biomedical research serving basic, translational, and clinical research projects. In this article, we describe 2 models of biobanking and tissue preservation with different approaches and aims. Archive tissue biobanking is described here as a resource of residual pathology tissues for translational research, which represents the huge clinical heterogeneity. In this context, managing of tissues and RNA quality in archive tissue are discussed. The other model of tissue biobanking is referred to as xenograft tissue banking, which represents an alternative method for obtaining large amounts of tissue, over an indefinite period, in so far as the tumor can be transferred in vivo over generations, maintaining the histological and genetic particularities. A description of the method and examples of the application are given with particular emphasis on sarcomas (Ewing's sarcoma/primitive neuroectodermal sarcoma, synovial sarcomas, and rhabdomyosarcomas) and early stages of tumor angiogenesis in sarcomas.

Is human papillomavirus associated with prostate cancer survival?

The role of human papillomavirus (HPV) in prostate carcinogenesis is highly controversial: some studies suggest a positive association between HPV infection and an increased risk of prostate cancer (PCa), whereas others do not reveal any correlation. In this study, we investigated the prognostic impact of HPV infection on survival in 150 primary PCa patients. One hundred twelve (74.67%) patients had positive expression of HPV E7 protein, which was evaluated in tumour tissue by immunohistochemistry. DNA analysis on a subset of cases confirmed HPV infection and revealed the presence of genotype 16. In Kaplan-Meier analysis, HPV-positive cancer patients showed worse overall survival (OS) (median 4.59 years) compared to HPV-negative (median 8.24 years, P = 0.0381). In multivariate analysis age (P < 0.001), Gleason score (P < 0.001), nuclear grading (P = 0.002), and HPV status (P = 0.034) were independent prognostic factors for OS. In our cohort, we observed high prevalence of HPV nuclear E7 oncoprotein and an association between HPV infection and PCa survival. In the debate about the oncogenic activity of HPV in PCa, our results further confirm the need for additional studies to clarify the possible role of HPV in prostate carcinogenesis.

Are breast cancer molecular classes predictive of survival in patients with long follow-up?

In this study we investigate the clinical outcomes of 305 breast cancer (BC) patients, aged 55 years or younger, with long follow-up and according to intrinsic subtypes. The cohort included 151 lymph node negative (LN-) and 154 lymph node positive (LN+) patients. Luminal A tumors were mainly LN-, well differentiated, and of stage I; among them AR was an indicator of good prognosis. Luminal B and HER2 positive nonluminal cancers showed higher tumor grade and nodal metastases as well as higher proliferation status and stage. Among luminal tumors, those PR positive and vimentin negative showed a longer survival. HER2-positive nonluminal and TN patients showed a poorer outcome, with BC-specific death mostly occurring within 5 and 10 years. Only luminal tumor patients underwent BC death over 10 years. When patients were divided in to LN- and LN+ no differences in survival were observed in the luminal subgroups. LN- patients have good survival even after 20 years of follow-up (about 75%), while for LN+ patients survival at 20 years (around 40%) was comparable to HER2-positive nonluminal and TN groups. In conclusion, in our experience ER-positive breast tumors are better divided by classical clinical stage than molecular classification, and they need longer clinical follow-up especially in cases with lymph node involvement.

Inhibition of GSK3B bypass drug resistance of p53-null colon carcinomas by enabling necroptosis in response to chemotherapy

PURPOSE

Evasion from chemotherapy-induced apoptosis due to p53 loss strongly contributes to drug resistance. Identification of specific targets for the treatment of drug-resistant p53-null tumors would therefore increase the effectiveness of cancer therapy.

EXPERIMENTAL DESIGN

By using a kinase-directed short hairpin RNA library and HCT116p53KO drug-resistant colon carcinoma cells, glycogen synthase kinase 3 beta (GSK3B) was identified as a target whose silencing bypasses drug resistance due to loss of p53. p53-null colon cancer cell lines with different sets of mutations were used to validate the role of GSK3B in sustaining resistance and to characterize cell death mechanisms triggered by chemotherapy when GSK3B is silenced. In vivo xenograft studies were conducted to confirm resensitization of drug-resistant cells to chemotherapy upon GSK3 inhibition. Colon cancer samples from a cohort of 50 chemotherapy-treated stage II patients were analyzed for active GSK3B expression.

RESULTS

Downregulation of GSK3B in various drug-resistant p53-null colon cancer cell lines abolished cell viability and colony growth after drug addition without affecting cell proliferation or cell cycle in untreated cells. Cell death of 5-fluorouracil (5FU)-treated p53-null GSK3B-silenced colon carcinoma cells occurred via PARP1-dependent and AIF-mediated but RIP1-independent necroptosis. In vivo studies showed that drug-resistant xenograft tumor mass was significantly reduced only when 5FU was given after GSK3B inhibition. Tissue microarray analysis of colon carcinoma samples from 5FU-treated patients revealed that GSK3B is significantly more activated in drug-resistant versus responsive patients.

CONCLUSIONS

Targeting GSK3B, in combination with chemotherapy, may represent a novel strategy for the treatment of chemotherapy-resistant tumors.

Management of stage II colon cancer - the use of molecular biomarkers for adjuvant therapy decision

BACKGROUND

There is uncertainty on the benefit of adjuvant chemotherapy in patients with stage II colorectal cancers. The aim of this study is to investigate the combined role of clinical, pathological and molecular parameters to identify those stage II patients who better benefit from adjuvant therapy.

METHODS

We examined 120 stage II colon cancer patients. Of these, 60 patients received adjuvant 5-FU chemotherapy after surgery and the other 60 did not receive therapy. Immunohistochemical (IHC) analyses were performed to evaluate the expressions of Thymidylate synthetase (TYMS), TP53 (p53), β-catenin (CTNNB1) and CD8. For TYMS, its mRNA expression levels were also investigated by real time qRT-PCR. The entire case study was characterized by the presence of a defect in the MMR (mismatch repair) system, the presence of the CpG island methylator phenotype (CIMP or CIMP-High) and for the V600E mutation in the BRAF gene. At the histo-pathological level, the depth of tumour invasion, lymphovascular invasion, invasion of large veins, host lymphocytic response and tumour border configuration were recorded.

RESULTS

The presence of the V600E mutation in the BRAF gene was a poor prognostic factor for disease free and overall survival (DFS; hazard ratio [HR], 2.57; 95% CI: 1.03 -6.37; p = 0.04 and OS; HR, 3.68; 95% CI: 1.43-9.47; p < 0.01 respectively), independently of 5-FU treatment. Adjuvant therapy significantly improved survival in patients with high TYMS levels (p = 0.04), while patients with low TYMS had a better outcome if treated by surgery alone (DFS; HR, 6.07; 95% CI, 0.82 to 44.89; p = 0.04). In patients with a defect in the MMR system (dMMR), 5-FU therapy was associated to reduced survival (DFS; HR, 37.98; 95% CI, 1.04 to 1381.31; p = 0.04), while it was beneficial for CIMP-High associated tumours (DFS; HR, 0.17; 95% CI, 0.02 to 1.13; p = 0.05).

CONCLUSIONS

Patients' characterization according to MMR status, CIMP phenotype and TYMS mRNA expression may provide a more tailored approach for adjuvant therapy in stage II colon cancer.

Desmosomes in verrucous carcinoma of the head and neck

Verrucous carcinoma (VC) is a variant of squamous cell carcinoma (SCC), characterised by its inability to metastasize. In contrast, hybrid carcinomas, composed of VC and foci of conventional SCC, harbour a metastatic potential. Correct pathohistological diagnosis is therefore crucial for the choice of treatment. There is mounting evidence that desmosomes are involved in several aspects of carcinogenesis. Previous studies have shown an altered expression of desmosomal components in conventional SCC, which was associated with tumour behaviour, but no data have been found on desmosomes in VC. We therefore analysed the expression of desmosomal components in biopsy samples of 21 cases of VC and 5 cases of hybrid carcinoma of the head and neck in comparison to 23 cases of conventional SCC and 47 samples of normal squamous epithelium of similar localisation, using immunohistochemistry and real-time reverse-transcription polymerase chain reaction. We found that the expression patterns of desmosomal components in VC were fairly similar to those in normal epithelium but differed significantly from those in conventional SCC. Immunohistochemical reactions against desmosomal components disclosed the foci of SCC in hybrid carcinomas. In conclusion, we believe that expression patterns of desmosomal components in VC are consistent with its less aggressive behaviour. Differential expression of desmosomal components between VC and SCC makes some desmosomal components potentially useful in the diagnostics of VC, especially for the detection of hybrid carcinoma.

Prevalence of different subtypes of serrated polyps and risk of synchronous advanced colorectal neoplasia in average-risk population undergoing first-time colonoscopy

OBJECTIVES:

A growing body of evidence indicates that patients with sessile serrated adenoma/polyp (SSA/P) and traditional serrated adenoma (TSA) are at risk for subsequent malignancy. Despite increasing knowledge on histological categorization of serrated polyps (SPs) data are lacking on the actual prevalence and the association of each SP subtype with advanced colorectal neoplasia.

METHODS:

We prospectively determined the prevalence of different SP subtypes and evaluate the association with synchronous advanced neoplasia in asymptomatic average-risk subjects undergoing first-time colonoscopy. All retrieved polyps were examined by two independent pathologists. Serrated lesions were classified into hyperplastic polyps (HP), SSA/P (without and with cytological dysplasia, SSA/P/DIS), and TSA, and were screened for BRAF and K-ras mutations.

RESULTS:

Among 258 polyps detected in 985 subjects, the proportion of SSA/P and TSA was 8.9% and 1.9% with an overall prevalence of 2.3% and 0.6%, respectively. SSA/Ps were small without significant difference in their location between proximal and distal colon; TSA were predominantly left-sided. BRAF mutation was common in SSA/Ps and K-ras mutation was present in all TSA. Independent predictors of advanced neoplasia were male sex (odds ratio (OR)=2.0, 95% confidence interval (CI) 1.0–4.0), increasing age (OR=4.5, 95% CI 1.5–13.4 for 50–69 years and OR=9.9, 95% CI 3.1–31.5 for >70 years), current smoking (OR=2.0, 95% CI 1.3–6.8), >3 tubular adenoma (OR=3.6, 95% CI 1.9–6.4), and SSA/P (OR=6.0, 95% CI 1.9–19.5).

CONCLUSIONS:

The substantial prevalence of BRAF-mutated SSA/P and the independent association with synchronous advanced colorectal neoplasia in asymptomatic average-risk subjects support the overall impact of the serrated pathway on colorectal cancer (CRC) risk in general population. The endoscopic characteristics of SSA/P emphasize the need of high-quality colonoscopy as a key factor for an effective CRC screening program.

The human RECQ1 helicase is highly expressed in glioblastoma and plays an important role in tumor cell proliferation

Background

RecQ helicases play an essential role in the maintenance of genome stability. In humans, loss of RecQ helicase function is linked with predisposition to cancer and/or premature ageing. Current data show that the specific depletion of the human RECQ1 helicase leads to mitotic catastrophe in cancer cells and inhibition of tumor growth in mice.

Results

Here, we show that RECQ1 is highly expressed in various types of solid tumors. However, only in the case of brain gliomas, the high expression of RECQ1 in glioblastoma tissues is paralleled by a lower expression in the control samples due to the poor expression of RECQ1 in non-dividing tissues. This conclusion is validated by immunohistochemical analysis of a tissue microarray containing 63 primary glioblastomas and 19 perilesional tissue samples, as control. We also show that acute depletion of RECQ1 by RNAi results in a significant reduction of cellular proliferation, perturbation of S-phase progression, and spontaneous γ-H2AX foci formation in T98G and U-87 glioblastoma cells. Moreover, RECQ1 depleted T98G and U-87 cells are hypersensitive to HU or temozolomide treatment.

Conclusions

Collectively, these results indicate that RECQ1 has a unique and important role in the maintenance of genome integrity. Our results also suggest that RECQ1 might represent a new suitable target for anti cancer therapies aimed to arrest cell proliferation in brain gliomas.

A multicenter study to validate the reproducibility of MSI testing with a panel of 5 quasimonomorphic mononucleotide repeats

Microsatellite instability (MSI) testing in clinics is becoming increasingly widespread; therefore, there is an urgent need for methodology standardization and the availability of quality control. This study is aimed to assess the interlaboratory reproducibility of MSI testing in archive samples by using a panel of 5 recently introduced, mononucleotide repeats (MNR). The quality control involved 8 European institutions. Participants were supplied with DNA extracted from 15 archive colon carcinoma samples and from the corresponding normal tissues. Every group was asked to assess the MSI status of the samples by using the BAT25, BAT26, NR21, NR24, and NR27 mononucleotide markers. Four institutions repeated the analysis using the NCI reference panel to confirm the results obtained with the MNR markers. The overall concordance among institutions for MSI analyses at single locus level was 97.7% when using the MNR panel and 95.0% with the NCI one. The laboratories obtained a full agreement in scoring the MSI status of each patient sample, both using the mononucleotide and the NCI marker sets. With the NCI marker set, however, concordance was lowered to 85.7% when considering the MSI-Low phenotype. Concordance between the 2 panels in scoring the MSI status of each sample was complete if no discrimination was made between MSI-Stable and MSI-L, whereas it dropped to 76.7% if MSI-L was considered. In conclusion, the use of the MNR panel seems to be a robust approach that yields a very high level of reproducibility. The results obtained with the 5 MNR are diagnostically consistent with those obtained by the use of the NCI markers, except for the MSI-Low phenotype.

Gene expression changes in peripheral blood mononuclear cells in occupational exposure to nickel

Allergic contact dermatitis is preceded by a clinically silent phase of sensitisation. In this study, we investigated whether the expression levels of six genes were related to nickel exposure and/or nickel sensitisation, and whether they could predict allergic manifestations to nickel. The mRNA expression level of six genes involved in cell growth (PIM1 and ETS2), metabolism/synthesis (HSD11B1 and PRDX4), apoptosis (CASP8) and signal transduction (CISH) was investigated by means of quantitative real-time RT-PCR in a cohort of 110 subjects, including healthy controls (n=51), nickel-exposed workers (n=23) and patients allergic to nickel (n=36). Our findings show that the expression levels of the analysed genes did not differ between allergic patients and healthy controls, while higher expression levels of ETS2 and CASP8 were detected in the nickel-exposed workers. Changes in ETS2 and CASP8 expression are likely to be related to nickel exposure rather than to allergy.

Multicentre validation study of nucleic acids extraction from FFPE tissues

In most pathology laboratories worldwide, formalin-fixed paraffin embedded (FFPE) samples are the only tissue specimens available for routine diagnostics. Although commercial kits for diagnostic molecular pathology testing are becoming available, most of the current diagnostic tests are laboratory-based assays. Thus, there is a need for standardized procedures in molecular pathology, starting from the extraction of nucleic acids. To evaluate the current methods for extracting nucleic acids from FFPE tissues, 13 European laboratories, participating to the European FP6 program IMPACTS (www.impactsnetwork.eu), isolated nucleic acids from four diagnostic FFPE tissues using their routine methods, followed by quality assessment. The DNA-extraction protocols ranged from homemade protocols to commercial kits. Except for one homemade protocol, the majority gave comparable results in terms of the quality of the extracted DNA measured by the ability to amplify differently sized control gene fragments by PCR. For array-applications or tests that require an accurately determined DNA-input, we recommend using silica based adsorption columns for DNA recovery. For RNA extractions, the best results were obtained using chromatography column based commercial kits, which resulted in the highest quantity and best assayable RNA. Quality testing using RT-PCR gave successful amplification of 200 bp-250 bp PCR products from most tested tissues. Modifications of the proteinase-K digestion time led to better results, even when commercial kits were applied. The results of the study emphasize the need for quality control of the nucleic acid extracts with standardised methods to prevent false negative results and to allow data comparison among different diagnostic laboratories.

Evidence of multiple infectious agents in mycosis fungoides lesions

The etiology of mycosis fungoides (MF) remains to be determined. Several studies have proposed a viral etiology with controversial results. In this case-control study we investigated the presence of Epstein-Barr virus (EBV) and the debated presence of Human T-cell lymphotrophic virus I (HTLV-I) sequences, by polymerase chain reaction on nucleic acid extracts from formalin-fixed paraffin-embedded skin biopsies. Moreover, by a multivariate approach we analyzed in the same case-control study also the contribution of two previously examined pathogens: Hepatitis C virus (HCV) and Borrelia burgdorferi (Bb). Significant differences in the frequency of infectious agents in cases and controls were detected for Bb, HTLV-I and EBV. In MF patients we found the concurrent presence of two or three of these pathogen sequences in 21 out of 83 cases, but only in 1 out of 83 healthy controls. Our results suggest that the persistence of multiple infectious agents may cause a long-term antigenic stimulation contributing to the malignant transformation of T lymphocytes, especially when associated with HTLV-I like sequences. However, these infectious agents do not seem to have effects on disease progression.

Pathology as the cornerstone of human tissue banking: European consensus expert group report

Aside from ethical considerations, the primary requirement for usage of human tissues in basic or translational research is the thorough characterization of tissues. The second, but equally essential, requirement is that tissues be collected, processed, annotated, and preserved in optimal conditions. These requirements put the pathologist at the center of tissue banking activities and of research aimed at discovering new biomarkers. Pathologists not only provide information identifying the specimen but also make decisions on what materials should be biobanked, on the preservation conditions, and on the timeline of events that precede preservation and storage. This central position calls for increased recognition of the role of the pathologist by the biomolecular community and places new demands on the pathologist's workload and scope of scientific activities. These questions were addressed by an Expert Group Meeting of the European Biological and Biomolecular Research Infrastructure (BBMRI). While detailed recommendations are published elsewhere (Bevilacqua et al., Virchows Archivs, 2010, in press), this article outlines the strategic and technological issues identified by the Expert Group and identifies ways forward for better integration of pathology in the current thrust for development of biomarker-based "personalized medicine."

Higher random oligo concentration improves reverse transcription yield of cDNA from bioptic tissues and quantitative RT-PCR reliability

Real time quantitative reverse transcription-PCR (qRT-PCR) is the most sensitive technique for detection and quantification of mRNA targets. Reliable quantification of gene expression in formalin-fixed, paraffin-embedded tissues (FFPE), however, has been subjected to serious limitations so far, mainly due to the fragmentation of RNA transcripts. We tried to improve the sensitivity and reliability of mRNA quantification in FFPE by boosting the reverse transcription (RT) step, that is neglected in most of the protocol analysis, but that represents the first confounding event in a quantitative analysis. For this purpose, we compared yield, reproducibility and linearity of RTs performed with random hexamers, random pentadecamers, or a mixture of antisense specific primers in presence of either Moloney murine leukemia virus (MmLV) or the avian myeloblastosis virus (AMV) enzymes. Random primers were tested at two concentrations, 0.14 and 3.35 nmol/reaction. Our qRT-PCR results indicate an improvement of RT yield when using the highest concentration of random oligos with MmLV (from -1.4 to -4.1 C(t)s) in comparison to the lowest concentration. Moreover, more reliable standard curves and therefore, efficiencies were obtained. RT reactions performed with specific primers and AMV were those with the highest yield, but efficiencies were unreliable, due to the RT enzyme-driven PCR inhibition. Random priming at the 3.35 nmol/reaction concentration seems to be the most convenient strategy in assays using RNA obtained from FFPE tissues.

[Time trend in cancer incidence among 0-24 year-old residents of the Province of Trieste, Italy, 1972-2003]

OBJECTIVE

to report and analyse time trends in cancer incidence among children (0-14 years of age), adolescents (15-19 years) and young adults (20-24 years) living in the Italian province of Trieste (2003 population, 242,000), between 1972 and 2003.

DESIGN

population-based study of descriptive epidemiology.

SETTING AND PARTICIPANTS

the new cases of cancer diagnosed to the residents of the province of Trieste below 25 years of age were extracted from the database of the Trieste Cancer Registry (period 1972-1994) and from the database of the Friuli-Venezia Giulia Cancer Registry (period 1995-2003), according to the International Classification of Childhood Cancer (3rd edition).

MAIN OUTCOME MEASURES

age-specific and age-standardized (Italian 1981 census population as standard) incidence rates, by diagnostic group, sex and period of diagnosis. Time trend in incidence was analysed by using a Poisson regression model adjusted for calendar year, sex and 5 year age-group, and was expressed as annual percent change (APC) in rates.

RESULTS

in the period 1972-2003, the new cases of cancer were 168 in the age-group 0-14 years, 79 in the age-group 15-19 years and 111 in the age-group 20-24 years, while the person-years at risk were respectively: 1,050,027; 431,673; 496,450. The APC in the incidence of all cancers combined was 2.3% (IC 95% 0.6%-3.9%) in children, 4.4% (IC 95% 1.8%-7.1%) in adolescents and 5.1% (IC 95% 2.8%-7.5%) in young adults. Hodgkin lymphomas (APC =12.7%; IC 95% 2.6%-23.7%; 7 cases) in the age-group 0-14 years, skin melanomas and carcinomas (APC =8.2%; IC 95% 4.5%-12.0%; 49 cases) and central nervous system tumours (APC = 6.4%; IC 95% 1.5%-11.5%; 25 cases) in the age-group 15-24 years were the malignancies characterised by the highest increase in incidence.

CONCLUSION

the increase in incidence rates observed in this study can be only partly explained by the small number of ascertained cases, by an improvement in diagnostic techniques and by more efficient registration. However, few environmental and hereditary factors are consistently associated with cancers affecting young people. Therefore, it is imperative to continue to carry out descriptive and analytical studies with primary prevention as the ultimate aim.

Prostate-tumor-inducing gene-1 analysis in human prostate cancer cells and tissue in relation to Mycoplasma infection

The potential role of PTI-1, in the natural story of prostate adenocarcinoma remains to be fully determined. PTI-1 expression was evaluated in human prostate cancer cell lines and in paraffin-embedded archive tissues. PTI-1 expression was found in Mycoplasma infected but not in non-infected cells. The lack of PTI-1 expression was also confirmed in fixed and paraffin-embedded human cancer prostate biopsies. The overall data indicate that, in prostate tumor cell lines, PTI-1 presence parallels Mycoplasma infection suggesting that PTI-1 might not necessarily play a major role in the onset of prostate tumorigenesis.