[The adjuvant killing effect of modulated electro-hyperthermia combined with chemotherapy on B16F10 melanoma cells]

Our aim was to detect the effect of modulated electro-hyperthermia (mEHT) on cell viability and to examine if hyperthermia can augment the cell killing effect of various chemotherapeutic agents. B16F10 melanoma cells were treated for 30, 60, 90 and 120 minutes with mEHT using LabEHY100 (OncothermTM). Cell viability was measured using MTT assay and apoptosis by annexin V/7-AAD staining using flow cytometry 24 hours post-treatment. For analyzing gene expression with qPCR cells were harvested after 60 minutes treatment. In combined protocols, cells were treated with paclitaxel (40 nM), dacarbazine (40 μM) or nutlin-3a (10 μM) after mEHT. mEHT induced nuclear translocation of p53 which in turn regulates pro- and anti-apoptotic gene expression accounting for decreased cell viability. In combination with chemotherapy, mEHT augmented the cell killing effect of dacarbazine or nutlin-3a but not that of paclitaxel determined 48 hours post-treatment. The sensitizing effect on chemotherapeutics demonstrate the efficiency of mEHT as an adjuvant modality in cancer treatment.

Prevalence of APC and PTEN Alterations in Urachal Cancer

Urachal carcinoma (UrC) is a rare tumor with remarkable histological and molecular similarities to colorectal cancer (CRC). Adenomatous polyposis coli (APC) is the most frequently affected gene in CRC, but the prevalence and significance of its alterations in UrC is poorly understood. In addition, loss of phosphatase and tensin homologue (PTEN) was shown to be associated with therapy resistance in CRC. Our primary aim was to assess specific genetic alterations including APC and PTEN in a large series of UrC samples in order to identify clinically significant genomic alterations. We analyzed a total of 40 UrC cases. Targeted 5-gene (APC, PTEN, DICER1, PRKAR1A, TSHR, WRN) panel sequencing was performed on the Illumina MiSeq platform (n = 34). In addition, ß-catenin (n = 38) and PTEN (n = 30) expressions were assessed by immunohistochemistry. APC and PTEN genes were affected in 15% (5/34) and 6% (2/34) of cases. Two of five APC alterations (p.Y1075*, p.K1199*) were truncating pathogenic mutations. One of the two PTEN variants was a pathogenic frameshift insertion (p.C211fs). In 29% (11/38) of samples, at least some weak nuclear ß-catenin immunostaining was detected and PTEN loss was observed in 20% (6/30) of samples. The low prevalence of APC mutations in UrC represents a characteristic difference to CRC. Based on APC and ß-catenin results, the Wnt pathway seems to be rarely affected in UrC. Considering the formerly described involvement of PTEN protein loss in anti-EGFR therapy-resistance its immunohistochemical testing may have therapeutic relevance.

[Preclinical and clinical investigation and development of electromagnetic oncological device - experience with solid tumors]

Our objective was to develop an electromagnetic tumor therapy device in a consortial cooperation between Semmelweis University and Oncotherm Ltd., to provide data and contribute to the development of the next generation of devices through preclinical, clinical and developmental modules via in vivo, in vitro studies, and patient treatments. Our numerous preclinical studies support the efficacy of mEHT. Clinical treatments were performed in 181 patients with inoperable and/or oligometastatic solid tumors. The protocols were developed, an international guideline was completed, and the planned steps of device development were realized. By optimizing previous selective RF techniques based on recent research findings, we can provide the most modern evidence-based treatment in the future.

Mutations of KRAS, NRAS, BRAF, EGFR, and PIK3CA genes in urachal carcinoma: Occurence and prognostic significance

Purpose

Targeted therapy represents an attractive alternative for rare tumors such as urachal carcinoma (UrC). The aim of this study was to assess the mutations of the most commonly affected 5 genes in the targetable EGFR-pathway in UrC and comapre their frequencies to those of found in urothelial and colorectal cancer.

Materials and Methods

Mutational hot-spots of selected genes were tested in 22 UrC samples by pyrosequencing. Mutational patterns were compared to those published for colorectal and urothelial cancers. Furthermore, we sought correlations between mutations and clinicopathological and follow-up data.

Results

We found 11 mutations in 10 of 22 (45%) patients. The most frequently mutated gene was KRAS (27%) followed by BRAF (18%) and NRAS (5%), while no mutations were detected in the EGFR and PIK3CA genes. No correlation was found between the mutation status and clinicopathological parameters (Sheldon/Mayo stage, tumor grade, metastases). Furthermore, none of the mutations correlated with progression-free or overall survival.

Conclusions

The mutation pattern of UrC is more similar to colorectal than to urothelial cancer. However, the mutation characteristics of UrC seems to be unique suggesting that clinical decision-making for UrC cannot be simply adopted from urothelial or colorectal carcinoma. The high occurence of EGFR-pathway mutations warrants the testing for KRAS and BRAF mutations when considering anti-EGFR therapy in UrC.

[Clinico-pathologically focused breast cancer research]

In the second half of the 20th century research focusing to breast carcinomas at the Semmelweis University had been mostly linked to the 2nd Department of Pathology. Nowadays, following the rapidly improving treatment modalities in breast cancer there is an increasing need for defining new predictive and prognostic markers. The modern molecular pathological approach helps tremendously in mapping the biological behavior of individual cases of breast cancers and meanwhile, it is one of the prerequisites of a more efficient treatment both in neoadjuvant and adjuvant settings, as well as in metastatic disease. We provide a brief review of the relevant results we have obtained in breast cancer research between 2000 and 2015.

[Significance of positive surgical margin in radical prostatectomy]

The optimal oncological result of radical prostatectomy (RP) is complete removal of the prostate gland and seminal vesicles with negative surgical margins. Preoperative diagnostic biopsies are examined and reported by the pathologist according to standardized rules. Staging of the disease is based on modern preoperative image analysis, most commonly multiparametric MRI. Pathological assessment and reporting of RP specimens is based on the International Society of Uropathology guidelines issued by the 2009 Consensus Conference. Positive surgical margin (PSM) is reported by the pathologist in approximately 1/3rd of RP cases. PSM increases the risk of biochemical, local and systemic progression. Pseudo-whole mount assessment of these specimens is the basis for radio-pathological correlation, thus providing quality control for preoperative MRI as well as assisting preoperative image analysis, sampling and diagnostic workup.

A meta-analysis of gene expression-based biomarkers predicting outcome after tamoxifen treatment in breast cancer

To date, three molecular markers (ER, PR, and CYP2D6) have been used in clinical setting to predict the benefit of the anti-estrogen tamoxifen therapy. Our aim was to validate new biomarker candidates predicting response to tamoxifen treatment in breast cancer by evaluating these in a meta-analysis of available transcriptomic datasets with known treatment and follow-up. Biomarker candidates were identified in Pubmed and in the 2007-2012 ASCO and 2011-2012 SABCS abstracts. Breast cancer microarray datasets of endocrine therapy-treated patients were downloaded from GEO and EGA and RNAseq datasets from TCGA. Of the biomarker candidates, only those identified or already validated in a clinical cohort were included. Relapse-free survival (RFS) up to 5 years was used as endpoint in a ROC analysis in the GEO and RNAseq datasets. In the EGA dataset, Kaplan-Meier analysis was performed for overall survival. Statistical significance was set at p < 0.005. The transcriptomic datasets included 665 GEO-based and 1,208 EGA-based patient samples. All together 68 biomarker candidates were identified. Of these, the best performing genes were PGR (AUC = 0.64, p = 2.3E-07), MAPT (AUC = 0.62, p = 7.8E-05), and SLC7A5 (AUC = 0.62, p = 9.2E-05). Further genes significantly correlated to RFS include FOS, TP53, BTG2, HOXB7, DRG1, CXCL10, and TPM4. In the RNAseq dataset, only ERBB2, EDF1, and MAPK1 reached statistical significance. We evaluated tamoxifen-resistance genes in three independent platforms and identified PGR, MAPT, and SLC7A5 as the most promising prognostic biomarkers in tamoxifen treated patients.

[Claudins as prognostic factors of breast cancer]

Different expression of claudins and E-cadherin has been described in the pathogenesis and progression of breast cancer. Changes in the expression of these junctional molecules have also been described as being of prominent importance in other cancers as well. Thus, we aimed at exploring the potential prognostic relevance of these cell junctional molecules in breast carcinoma cases. Expression of claudin-1, -3, -4, -5, -7, -8, -10, -15, -18 and E-cadherin at mRNA level was evaluated in correlation with survival in publicly available datasets containing expression measurements of 1809 breast cancer patients. Breast cancer tissues of 636 patients were evaluated with tissue microarray technique and immunohistochemical method for claudin-1, -2, -3, -4, -5, -7 and E-cadherin protein expression. In 96 cases lymph node metastases were also subjects of the study. Claudin expression bears prognostic information in itself. Based on bioinformatic data analysis, the meta-gene of claudin-3, -4, -7 and E-cadherin has proved the most powerful in predicting survival. An immunohistochemical protein profile consisting of claudin-2, -4 and E-cadherin was able to predict outcome in the most effective manner in the training set. Combining the overlapping members of the distinct methods resulted in the CC index (consisting of claudin-4 and E-cadherin, a.k.a. CURIO), which was able to accurately predict relapse-free survival in the validation cohort (p=0.029) in a more efficient way than its components. Cox regression analysis including clinicopathological variables and the average CC score showed that in univariate analysis most of them were prognostic but most of them lost independent prognostic value in multivariate analysis except for the CC index, the subtypes defined by immunoprofiling and vascular invasion. On the other hand, the CC index was able to further refine prognosis splitting good vs. poor prognosis patients into two clusters in these subgroups. Evaluation of lymph node metastases has shown that decreased expression of claudin-1 and elevated expression of claudin-4 can predict worse prognosis in breast cancers spreading to the regional lymph nodes. The defined claudin-cadherin index provides additional prognostic information besides the routinely utilized diagnostic approaches and factors. The level of expression of certain claudins can be of prognostic significance in regional lymph node metastases.

[Morphological and immunophenotypical heterogeneity in breast cancers of young and elderly women]

There is a reasonable heterogeneity in the morphological appearance and the immunohistochemical properties of distinct breast tumors. Furthermore, it is also known that cancer arising in young women have different prognosis than the ones developing in the elderly. We analyzed breast tumors of 41 young (<35 years) and 33 older women (>65 years) regarding histopathological properties and immunohistochemical reactions for ER, PgR, HER2 and Ki-67, as well as HER2 FISH. The longest diameters, thus largest available surface areas of the tumors were included in the evaluation. Different regions were marked for morphology and in all immunohistochemical reactions. The regions in the distinct tumors showing different pathological and immunohistochemical appearance were identical (p<0.001). The number of morphologically different tumor regions were more frequent in tumors developing in the young (1.82 vs. 1.48 regions/tumor), and 53.6% of tumors with heterogeneous architecture were in young vs. 39.4% in the elderly. However, regarding HER2 staining, cancers in the young patients have shown greater variability among the different tumor areas (p=0.007). The origin of tumor cells predicting prognosis remains undetermined. Whether the analysis of the expression pattern of the whole tumor is conducted or the minute regions are separately examined and averaged, the same results can be achieved. With the development of molecular techniques and accurate prognostic and treatment information rendered to samples the question may be soon answered.