Predictive value of angiogenic proteins in patients with metastatic melanoma treated with bevacizumab monotherapy

The incidence of malignant melanoma is rising worldwide and survival for metastatic disease is still poor. Recently, new treatment options have become available. Still, predictive biomarkers are needed to optimise treatment for this patient group. In this study, we investigated the predictive value of 60 angiogenic factors in patients with metastatic melanoma treated with the anti‐vascular endothelial growth factor A antibody bevacizumab. Thirty‐five patients were included in a clinical phase II trial and baseline serum samples were analysed by multiplex protein array. High‐serum concentration of Activin A was significantly associated with objective response (OR) to treatment (p = 0.014). Candidate proteins that indicated a borderline association with treatment response were further investigated by immunohistochemistry. Strong expression of Activin A, interleukin‐1β, and urokinase‐type plasminogen activator receptor in metastases was significantly associated with OR (p = 0.011, p = 0.003, and p = 0.007, respectively), as well as with markers of activated angiogenesis, such as higher number of proliferating vessels and the presence of glomeruloid microvascular proliferations. Our findings indicate that these proteins may be potential predictive markers for treatment with bevacizumab monotherapy.publishedVersio

The role of NF-κB transcription factor in cellular response to ionizing radiation

The NF-κB transcription factor is involved in different aspects of the cellular response to stress, including atypical NF-κB pathway activated by damage induced by ionizing radiation. Moreover, NF-κB could be involved in the regulation of genes activated by other stress-responsive factors. Here we aimed to perform the integrative genomics screening to compare subsets of NF-κB-dependent genes induced by a pro-inflammatory stimulus and a high dose of ionizing radiation and also to identify new genes potentially co-regulated by NF-κB and p53 transcription factors in irradiated cells. Methods. The RelA-containing NF-κB dimers were activated by TNFα cytokine (classical proinflammatory pathway) and a single 4 or 10 Gy dose (atypical radiation-induced pathway) in human osteosarcoma cells. NF-κB-dependent and p53-dependent genes were identified using the gene expression profiling (by RNA-Seq) in cells with downregulated RELA or TP53 combined with the global profiling of RelA and p53 binding sites (by ChIP-Seq). Candidate genes were subsequently validated by quantitative PCR. Results: There were 37 NF-κB-dependent protein-coding genes identified: in all cases RelA bound in their regulatory regions upon activation while downregulation of RELA suppressed their stimulus-induced upregulation, which apparently indicated the positive regulation mode (this set of genes included a few “novel” NF-κB-dependent species). The kinetics of the NF-κB activation was slower in cells exposed to radiation than in cytokine-stimulated ones. However, subsets of NF-κB-dependent genes upregulated by both types of stimuli were essentially the same. Moreover, we identified a subset of radiation-modulated genes whose expression was affected by silencing of both TP53 and RELA, and a subset of radiation-upregulated genes where radiation stimulated binding of both p53 and RelA. For three genes an antagonistic effect of both transcription factors was observed: IL4I1 was activated by NF-κB and inhibited by p53, while CDKN1A and SERPINE1 were activated by p53 and inhibited by NF-κB. Moreover, RRAD was putatively co-activated by both factors. Conclusions: One could expect that similar cellular processes resulting from activation of the NF-κB pathway could be induced in cells responding to pro-inflammatory cytokines and in cells where so-called “sterile inflammation” response was initiated by radiation-induced damage. Moreover, certain stress-responsive genes induced by ionizing radiation could be co-regulated by NF-κB and p53.publishedVersio

Reduced expression of innate immunity-related genes in lymph node metastases of luminal breast cancer patients

Immune system plays a dual role in cancer by either targeting or supporting neoplastic cells at various stages of disease, including metastasis. Yet, the exact immune-related transcriptome profiles of primary tumours (PT) and lymph node metastases (LNM) and their evolution during luminal breast cancer (BCa) dissemination remain undiscovered. In order to identify the immune-related transcriptome changes that accompany lymphatic spread, we analysed PT-LNM pairs of luminal BCa using NanoString technology. Decrease in complement C3—one of the top-downregulated genes, in LNM was validated at the protein level using immunohistochemistry. Thirty-three of 360 analysed genes were downregulated (9%), whereas only 3 (0.8%) upregulated in LNM when compared to the corresponding PT. In LNM, reduced expression was observed in genes related to innate immunity, particularly to the complement system (C1QB, C1S, C1R, C4B, CFB, C3, SERPING1 and C3AR1). In validation cohort, complement C3 protein was less frequently expressed in LNM than in PT and it was associated with worse prognosis. To conclude, local expression of the complement system components declines during lymphatic spread of non-metastatic luminal BCa, whilst further reduction of tumoral complement C3 in LNM is indicative for poor survival. This points to context-dependent role of complement C3 in BCa dissemination.publishedVersio

Metabolomic and transcriptomic response to imatinib treatment of gastrointestinal stromal tumour in xenograft-bearing mice

Background Although imatinib is a well-established first-line drug for treating a vast majority of gastrointestinal stromal tumours (GIST), GISTs acquire secondary resistance during therapy. Multi-omics approaches provide an integrated perspective to empower the development of personalised therapies through a better understanding of functional biology underlying the disease and molecular-driven selection of the best-targeted individualised therapy. In this study, we applied integrative metabolomic and transcriptomic analyses to elucidate tumour biochemical processes affected by imatinib treatment. Materials and methods A GIST xenograft mouse model was used in the study, including 10 mice treated with imatinib and 10 non-treated controls. Metabolites in tumour extracts were analysed using gas chromatography coupled with mass spectrometry (GC-MS). RNA sequencing was also performed on the samples subset (n=6). Results Metabolomic analysis revealed 21 differentiating metabolites, whereas next-generation RNA sequencing data analysis resulted in 531 differentially expressed genes. Imatinib significantly changed the profile of metabolites associated mainly with purine and pyrimidine metabolism, butanoate metabolism, as well as alanine, aspartate, and glutamate metabolism. The related changes in transcriptomic profiles included genes involved in kinase activity and immune responses, as well as supported its impact on the purine biosynthesis pathway. Conclusions Our multi-omics study confirmed previously known pathways involved in imatinib anticancer activity as well as correlated imatinib-relevant downregulation of expression of purine biosynthesis pathway genes with the reduction of respectful metabolites. Furthermore, considering the importance of the purine biosynthesis pathway for cancer proliferation, we identified a potentially novel mechanism for the anti-tumour activity of imatinib. Based on the results, we hypothesise metabolic modulations aiming at the reduction in purine and pyrimidine pool may ensure higher imatinib efficacy or re-sensitise imatinib-resistant tumours.publishedVersio

Analysis options for high-throughput sequencing in miRNA expression profiling

Background: Recently high-throughput sequencing (HTS) using next generation sequencing techniques became useful in digital gene expression profiling. Our study introduces analysis options for HTS data based on mapping to miRBase or counting and grouping of identical sequence reads. Those approaches allow a hypothesis free detection of miRNA differential expression. Methods: We compare our results to microarray and qPCR data from one set of RNA samples. We use Illumina platforms for microarray analysis and miRNA sequencing of 20 samples from benign follicular thyroid adenoma and malignant follicular thyroid carcinoma. Furthermore, we use three strategies for HTS data analysis to evaluate miRNA biomarkers for malignant versus benign follicular thyroid tumors. Results: High correlation of qPCR and HTS data was observed for the proposed analysis methods. However, qPCR is limited in the differential detection of miRNA isoforms. Moreover, we illustrate a much broader dynamic range of HTS compared to microarrays for small RNA studies. Finally, our data confirm hsa-miR-197-3p, hsa-miR-221-3p, hsa-miR-222-3p and both hsa-miR-144-3p and hsa-miR-144-5p as potential follicular thyroid cancer biomarkers. Conclusions: Compared to microarrays HTS provides a global profile of miRNA expression with higher specificity and in more detail. Summarizing of HTS reads as isoform groups (analysis pipeline B) or according to functional criteria (seed analysis pipeline C), which better correlates to results of qPCR are promising new options for HTS analysis. Finally, data opens future miRNA research perspectives for HTS and indicates that qPCR might be limited in validating HTS data in detail.:Background; Methods; Results; Discussion; Conclusion

Unsupervised analysis of follicular thyroid tumours transcriptome by oligonucleotide microarray gene expression profiling

Wstęp: Rak pęcherzykowy tarczycy (FTC) jest nowotworem którego podłoże molekularne jest mało zbadane. W podjętej analizie transkryptomuoceniono możliwość dyskryminacji raka i gruczolaka pęcherzykowego tarczycy (FTA) na podstawie badań profilu ekspresjigenów metodą tzw. nienadzorowaną (tzn. na podstawie dominujących źródeł zmienności). Analizę tę prowadzono by sprawdzić czyzłośliwość guza jest rzeczywiście czynnikiem dominującym dla profilu ekspresji genów w nowotworach pęcherzykowych.Materiał i metody: Podstawowy zbiór guzów pęcherzykowych obejmował 52 próbki (27 FTC i 25 FTA), z których wyizolowano całkowityRNA i poddano badaniu na mikromacierzach HG-U133 Plus 2.0. Otrzymany zbiór normalizowano za pomocą RMA i GC-RMA. Identyfikacjigłównych źródeł zmienności dokonano metodą analizy głównych składowych (PCA).Wyniki: Analizę funkcji biologicznej genów przeprowadzono dla pierwszych 6 składowych głównych. Geny skorelowane z pierwsząskładową pozwalały wyodrębnić 2 klastry próbek: jeden złożony głównie z gruczolaków, z wysoką ekspresją między innymi transkryptówtarczycowo-swoistych, drugi zaś, zawierający większość raków, wykazywał zwiększoną, ale heterogenną ekspresję genów związanychz odpowiedzią immunologiczną, a obniżoną ekspresję genów tarczycowych. Geny odpowiedzi immunologicznej stwierdzono wśród transkryptów skorelowanych przebiegiem pierwszej, trzeciej i szóstej głównej składowej; w istotny sposób wpływały one na rozróżnieniemiędzy FTC i FTA.Wnioski: W analizie nienadzorowanej stwierdzono, że złośliwość (inwazyjność) nowotworu pęcherzykowego może być jednymz głównych źródeł zmienności w transkryptomie tych guzów. Jednak, genomiczna odległość między grupami FTC i FTA jest niewielka,a wyodrębnione w analizie nienadzorowanej klastry nakładają się, stąd sama analiza nienadzorowana nie jest wystarczającym narzędziemdo celów klasyfikacji tych guzów.(Endokrynol Pol 2013; 64 (5): 329–334)Introduction: Mechanisms driving the invasiveness of follicular thyroid cancer (FTC) are not fully understood. In our study, we undertookan unsupervised analysis of the set of follicular thyroid tumours (adenomas (FTA) and carcinomas) to verify whether the malignantphenotype influences major sources of variability in our dataset.Material and methods: The core set of samples consisted of 52 tumours (27 FTC, 25 FTA). Total RNA was analysed by oligonucleotidemicroarray (HG-U133 Plus 2.0). Principal Component Analysis (PCA) was applied as a main method of unsupervised analysis.Results: An analysis of biological character of genes correlated to the first six PCs was performed. When genes correlated to the first PCwere used to cluster FTC and FTA, they appeared in two branches; one, relatively enriched in adenomas, with homogenous expressionof subset of genes, and the other containing mainly carcinomas, with down-regulation of these genes and heterogeneous up-regulationin a smaller cluster of transcripts. Genes highly up-regulated in adenomas included some thyroid-specific transcripts. The second clusterof genes, up-regulated in carcinomas, contained mainly immunity-related transcripts. Immune response genes were found in the first,third and sixth principal components, improving the discrimination between carcinomas and adenomas.Conclusions: Our unsupervised analysis indicates that invasiveness of follicular tumours might be considered as the major source of variabilityin transcriptome analysis. However, the distance between both groups is small and the clusters are overlapping, thus, unsupervisedanalysis is not sufficient to properly classify them. (Endokrynol Pol 2013; 64 (5): 328–334

Heat shock factor 1 (Hsf1) cooperates with estrogen receptor α (erα) in the regulation of estrogen action in breast cancer cells

Heat shock factor 1 (HSF1), a key regulator of transcriptional responses to proteotoxic stress, was linked to estrogen (E2) signaling through estrogen receptor α (ERα). We found that an HSF1 deficiency may decrease ERα level, attenuate the mitogenic action of E2, counteract E2-stimulated cell scattering, and reduce adhesion to collagens and cell motility in ER-positive breast cancer cells. The stimulatory effect of E2 on the transcriptome is largely weaker in HSF1-deficient cells, in part due to the higher basal expression of E2-dependent genes, which correlates with the enhanced binding of unliganded ERα to chromatin in such cells. HSF1 and ERα can cooperate directly in E2-stimulated regulation of transcription, and HSF1 potentiates the action of ERα through a mechanism involving chromatin reorganization. Furthermore, HSF1 deficiency may increase the sensitivity to hormonal therapy (4-hydroxytamoxifen) or CDK4/6 inhibitors (palbociclib). Analyses of data from The Cancer Genome Atlas database indicate that HSF1 increases the transcriptome disparity in ER-positive breast cancer and can enhance the genomic action of ERα. Moreover, only in ER-positive cancers an elevated HSF1 level is associated with metastatic disease.publishedVersio

Reduced expression of OXPHOS and DNA damage genes is linked to protection from microvascular complications in long-term type 1 diabetes : the PROLONG study

Type 1 diabetes is a chronic autoimmune disease requiring insulin treatment for survival. Prolonged duration of type 1 diabetes is associated with increased risk of microvascular complications. Although chronic hyperglycemia and diabetes duration have been considered as the major risk factors for vascular complications, this is not universally seen among all patients. Persons with long-term type 1 diabetes who have remained largely free from vascular complications constitute an ideal group for investigation of natural defense mechanisms against prolonged exposure of diabetes. Transcriptomic signatures obtained from RNA sequencing of the peripheral blood cells were analyzed in non-progressors with more than 30 years of diabetes duration and compared to the patients who progressed to microvascular complications within a shorter duration of diabetes. Analyses revealed that non-progressors demonstrated a reduction in expression of the oxidative phosphorylation (OXPHOS) genes, which were positively correlated with the expression of DNA repair enzymes, namely genes involved in base excision repair (BER) machinery. Reduced expression of OXPHOS and BER genes was linked to decrease in expression of inflammation-related genes, higher glucose disposal rate and reduced measures of hepatic fatty liver. Results from the present study indicate that at transcriptomic level reduction in OXPHOS, DNA repair and inflammation-related genes is linked to better insulin sensitivity and protection against microvascular complications in persons with long-term type 1 diabetes.Peer reviewe

Diagnostic accuracy of liquid biopsy in endometrial cancer

Background: Liquid biopsy is a minimally invasive collection of a patient body fluid sample. In oncology, they offer several advantages compared to traditional tissue biopsies. However, the potential of this method in endometrial cancer (EC) remains poorly explored. We studied the utility of tumor educated platelets (TEPs) and circulating tumor DNA (ctDNA) for preoperative EC diagnosis, including histology determination. Methods: TEPs from 295 subjects (53 EC patients, 38 patients with benign gynecologic conditions, and 204 healthy women) were RNA-sequenced. DNA sequencing data were obtained for 519 primary tumor tissues and 16 plasma samples. Artificial intelligence was applied to sample classification. Results: Platelet-dedicated classifier yielded AUC of 97.5% in the test set when discriminating between healthy subjects and cancer patients. However, the discrimination between endometrial cancer and benign gynecologic conditions was more challenging, with AUC of 84.1%. ctDNA-dedicated classifier discriminated primary tumor tissue samples with AUC of 96% and ctDNA blood samples with AUC of 69.8%. Conclusions: Liquid biopsies show potential in EC diagnosis. Both TEPs and ctDNA profiles coupled with artificial intelligence constitute a source of useful information. Further work involving more cases is warranted.publishedVersio

Patient-derived organoids reflect the genetic profile of endometrial tumors and predict patient prognosis

Background: A major hurdle in translational endometrial cancer (EC) research is the lack of robust preclinical models that capture both inter- and intra-tumor heterogeneity. This has hampered the development of new treatment strategies for people with EC. Methods: EC organoids were derived from resected patient tumor tissue and expanded in a chemically defined medium. Established EC organoids were orthotopically implanted into female NSG mice. Patient tissue and corresponding models were characterized by mor- phological evaluation, biomarker and gene expression and by whole exome sequencing. A gene signature was defined and its prognostic value was assessed in multiple EC cohorts using Mantel-Cox (log-rank) test. Response to carboplatin and/or paclitaxel was measured in vitro and evaluated in vivo. Statistical difference between groups was calculated using paired t-test. Results: We report EC organoids established from EC patient tissue, and orthotopic organoid-based patient-derived xenograft models (O-PDXs). The EC organoids and O-PDX models mimic the tissue architecture, protein biomarker expression and genetic profile of the original tissue. Organoids show heterogenous sensitivity to conventional chemotherapy, and drug response is reproduced in vivo. The relevance of these models is further supported by the identification of an organoid-derived prognostic gene signature. This signature is vali- dated as prognostic both in our local patient cohorts and in the TCGA endometrial cancer cohort. Conclusions: We establish robust model systems that capture both the diversity of endo- metrial tumors and intra-tumor heterogeneity. These models are highly relevant preclinical tools for the elucidation of the molecular pathogenesis of EC and identification of potential treatment strategies.publishedVersio