MiR-106b-5p: A Master Regulator of Potential Biomarkers for Breast Cancer Aggressiveness and Prognosis.

Breast cancer (BCa) is the leading cause of death by cancer in women worldwide. This disease is mainly stratified in four subtypes according to the presence of specific receptors, which is important for BCa aggressiveness, progression and prognosis. MicroRNAs (miRNAs) are small non-coding RNAs that have the capability to modulate several genes. Our aim was to identify a miRNA signature deregulated in preclinical and clinical BCa models for potential biomarker discovery that would be useful for BCa diagnosis and/or prognosis. We identified hsa-miR-21-5p and miR-106b-5p as up-regulated and hsa-miR-205-5p and miR-143-3p as down-regulated in BCa compared to normal breast or normal adjacent (NAT) tissues. We established 51 shared target genes between hsa-miR-21-5p and miR-106b-5p, which negatively correlated with the miRNA expression. Furthermore, we assessed the pathways in which these genes were involved and selected 12 that were associated with cancer and metabolism. Additionally, GAB1, GNG12, HBP1, MEF2A, PAFAH1B1, PPP1R3B, RPS6KA3 and SESN1 were downregulated in BCa compared to NAT. Interestingly, hsa-miR-106b-5p was up-regulated, while GAB1, GNG12, HBP1 and SESN1 were downregulated in aggressive subtypes. Finally, patients with high levels of hsa-miR-106b-5 and low levels of the abovementioned genes had worse relapse free survival and worse overall survival, except for GAB1.

Knockdown of PAICS inhibits malignant proliferation of human breast cancer cell lines.

BACKGROUND: Phosphoribosylaminoimidazole carboxylase, phosphoribosylaminoimidazole succinocarboxamide synthetase (PAICS), an enzyme required for de novo purine biosynthesis, is associated with and involved in tumorigenesis. This study aimed to evaluate the role of PAICS in human breast cancer, which remains the most frequently diagnosed cancer and the leading cause of cancer-related death among women in less developed countries. RESULTS: Lentivirus-based short hairpin RNA targeting PAICS specifically depleted its endogenous expression in ZR-75-30 and MDA-MB-231 breast cancer cells. Depletion of PAICS led to a significant decrease in cell viability and proliferation. To ascertain the mechanisms through which PAICS modulates cell proliferation, flow cytometry was performed, and it was confirmed that G1-S transition was blocked in ZR-75-30 cells through PAICS knockdown. This might have occurred partly through the suppression of Cyclin E and the upregulation of Cyclin D1, P21, and CDK4. Moreover, PAICS knockdown obviously promoted cell apoptosis in ZR-75-30 cells through the activation of PARP and caspase 3 and downregulation of Bcl-2 and Bcl-xl expression in ZR-75-30 cells. CONCLUSIONS: These findings demonstrate that PAICS plays an essential role in breast cancer proliferation in vitro, which provides a new opportunity for discovering and identifying novel effective treatment strategies.

Knockdown of PAICS inhibits malignant proliferation of human breast cancer cell lines

BACKGROUND: Phosphoribosylaminoimidazole carboxylase, phosphoribosylaminoimidazole succinocarboxamide synthetase (PAICS), an enzyme required for de novo purine biosynthesis, is associated with and involved in tumorigenesis. This study aimed to evaluate the role of PAICS in human breast cancer, which remains the most frequently diagnosed cancer and the leading cause of cancer-related death among women in less developed countries. RESULTS: Lentivirus-based short hairpin RNA targeting PAICS specifically depleted its endogenous expression in ZR-75-30 and MDA-MB-231 breast cancer cells. Depletion of PAICS led to a significant decrease in cell viability and proliferation. To ascertain the mechanisms through which PAICS modulates cell proliferation, flow cytometry was performed, and it was confirmed that G1-S transition was blocked in ZR-75-30 cells through PAICS knockdown. This might have occurred partly through the suppression of Cyclin E and the upregulation of Cyclin D1, P21, and CDK4. Moreover, PAICS knockdown obviously promoted cell apoptosis in ZR-75-30 cells through the activation of PARP and caspase 3 and downregulation of Bcl-2 and Bcl-xl expression in ZR-75-30 cells. CONCLUSIONS: These findings demonstrate that PAICS plays an essential role in breast cancer proliferation in vitro, which provides a new opportunity for discovering and identifying novel effective treatment strategies.

Predictive biomarker candidates to delineate efficacy of antiangiogenic treatment in renal cell carcinoma.

Antiangiogenic therapy is currently considered as the cornerstone of treatment in metastatic kidney cancer. A monoclonal antibody against the vascular endothelial growth factor (VEGF) and several tyrosine kinase inhibitors targeting the VEGF receptors demonstrated, 7 years ago, to deeply impact the outcome of this tumor and became a model of integration of molecular knowledge into clinical practice. Unfortunately, no further improvement in survival has been made and 20-25 % of cases remain primary refractory to these drugs, with an overall dismal prognosis. Since biomarker predictors of activity are lacking, their development could highly help in the process of making clinical decisions when choosing the best option for every patient or prompting the inclusion in clinical trials. This unmet medical need could become even more relevant if new immunotherapy confirms its initial promising results in this pathology. In this article, we provide an insight of current state of the art regarding the prediction of antiangiogenic efficacy in kidney cancer and propose new strategies for the implementation of such markers in clinical practice.

Cellular proliferation markers in peripheral and central fibromas: a comparative study.

OBJECTIVE: To perform a comparative study of the cellular proliferation in the peripheral and central fibromas. MATERIAL AND METHODS: Immunohistochemistry for PCNA and the AgNOR technique were performed in 9 cases of peripheral odontogenic fibroma (POF), in 4 cases of odontogenic fibroma (OdF), in 8 cases of peripheral ossifying fibroma (PEOF) and 7 cases of ossifying fibroma (OsF). The Kruskal-Wallis and Mann-Whitney tests were used for the statistical analyses. RESULTS: Mesenchymal component of the central lesions presented a higher mean number of AgNOR per nucleus and PCNA index than did the peripheral lesions (P≤0.05). The mean number of AgNOR per nucleus in the epithelial component proved to be higher in the OdF than in the POF (P≤0.05). The mesenchymal and epithelial components presented similar mean numbers of AgNOR per nucleus and PCNA index in the OdF, as well as a similar mean number of AgNOR per nucleus in the POF. CONCLUSIONS: The mesenchymal component may well play a role in the differences between the biological behaviour of the central lesions as compared to the peripheral lesions. Moreover, considering that the epithelial and mesenchymal components in odontogenic fibromas presented a similar proliferation index, more research is warranted to understand the true role of the epithelial components, which are believed to be inactive in nature, as well as in the development and biological behaviour of these lesions.

Syndecan-2 is upregulated in colorectal cancer cells through interactions with extracellular matrix produced by stromal fibroblasts.

BACKGROUND: The extracellular matrix (ECM) influences the structure, viability and functions of cells and tissues. Recent evidence indicates that tumor cells and stromal cells interact through direct cell-cell contact, the production of ECM components and the secretion of growth factors. Syndecans are a family of transmembrane heparan sulfate proteoglycans that are involved in cell adhesion, motility, proliferation and differentiation. Syndecan-2 has been found to be highly expressed in colorectal cancer cell lines and appears to be critical for cancer cell behavior. We have examined the effect of stromal fibroblast-produced ECM on the production of proteoglycans by colorectal cancer cell lines. RESULTS: Our results showed that in a highly metastatic colorectal cancer cell line, HCT-116, syndecan-2 expression is enhanced by fibroblast ECM, while the expression of other syndecans decreased. Of the various components of the stromal ECM, fibronectin was the most important in stimulating the increase in syndecan-2 expression. The co-localization of syndecan-2 and fibronectin suggests that these two molecules are involved in the adhesion of HCT-116 cells to the ECM. Additionally, we demonstrated an increase in the expression of integrins alpha-2 and beta-1, in addition to an increase in the expression of phospho-FAK in the presence of fibroblast ECM. Furthermore, blocking syndecan-2 with a specific antibody resulted in a decrease in cell adhesion, migration, and organization of actin filaments. CONCLUSIONS: Overall, these results show that interactions between cancer cells and stromal ECM proteins induce significant changes in the behavior of cancer cells. In particular, a shift from the expression of anti-tumorigenic syndecans to the tumorigenic syndecan-2 may have implications in the migratory behavior of highly metastatic tumor cells.

Cellular proliferation markers in peripheral and central fibromas: a comparative study

ABSTRACT Objective: To perform a comparative study of the cellular proliferation in the peripheral and central fibromas. Material and Methods: Immunohistochemistry for PCNA and the AgNOR technique were performed in 9 cases of peripheral odontogenic fibroma (POF), in 4 cases of odontogenic fibroma (OdF), in 8 cases of peripheral ossifying fibroma (PEOF) and 7 cases of ossifying fibroma (OsF). The Kruskal-Wallis and Mann-Whitney tests were used for the statistical analyses. Results: Mesenchymal component of the central lesions presented a higher mean number of AgNOR per nucleus and PCNA index than did the peripheral lesions (P≤0.05). The mean number of AgNOR per nucleus in the epithelial component proved to be higher in the OdF than in the POF (P≤0.05). The mesenchymal and epithelial components presented similar mean numbers of AgNOR per nucleus and PCNA index in the OdF, as well as a similar mean number of AgNOR per nucleus in the POF. Conclusions: The mesenchymal component may well play a role in the differences between the biological behaviour of the central lesions as compared to the peripheral lesions. Moreover, considering that the epithelial and mesenchymal components in odontogenic fibromas presented a similar proliferation index, more research is warranted to understand the true role of the epithelial components, which are believed to be inactive in nature, as well as in the development and biological behaviour of these lesions. .

Prognostic significance of c-erbB2 overexpression in patients with metastatic gastric cancer.

BACKGROUND: Overexpression of the gene c-erbB2, which encodes a receptor tyrosine kinase, has been associated with prognosis and response to therapy in several solid tumors. This study was designed to test whether c-erb-B2 overexpression can be related to prognosis of patients with metastatic gastric cancer. METHODS: Between 2005 and 2010, 46 cases of metastatic gastric cancer were evaluated immunohistochemically for c-erb-B2 overexpression. Overall survival (OS) and time-to-progression (TTP) served as the main outcome measures. RESULTS: c-erbB2 was overexpressed in 19 (41.3 %) cases and 8 patients (17.4 %) had a c-erbB2 score of 3+ (a strong complete membrane staining observed in >10 % of the tumor cells). c-erbB2 expression was not associated with the clinicohistological characteristics of the study participants. The mean OS was 11.48 ± 1.03 months, whereas the mean TTP was 8.28 ± 0.8 months. Compared with patients with a score of 2+ or less (n = 38), those with a c-erbB2 score of 3+ (n = 8) had both a significantly lower OS (15.55 ± 1.63 vs. 8.22 ± 0.88 months, respectively, p < 0.05) and TTP (10.72 ± 1.81 vs. 6.11 ± 0.61 months, respectively, p < 0.05). After allowance for potential confounders, Cox regression analysis identified a c-erbB2 score of 3+ as an independent predictor of both OS (hazard ratio = 1.9; 95 % confidence interval = 1.1-3.7, p < 0.05) and TTP (hazard ratio = 1.8; 95 % confidence interval = 1.1-4.1, p < 0.05). CONCLUSION: Our results suggest that c-erbB-2 overexpression may have a prognostic significance in patients with metastatic gastric cancer.

Expression profile of apoptosis-related genes in childhood adrenocortical tumors: low level of expression of BCL2 and TNF genes suggests a poor prognosis.

BACKGROUND: Impaired apoptosis has been implicated in the development of childhood adrenocortical tumors (ACT), although the expression of apoptosis-related gene expression in such tumors has not been reported. METHODS: The mRNA expression levels of the genes CASP3, CASP8, CASP9, FAS, TNF, NFKB, and BCL2 were analyzed by quantitative real-time PCR in consecutive tumor samples obtained at diagnosis from 60 children with a diagnosis of ACT and in 11 non-neoplastic adrenal samples. BCL2 and TNF protein expression was analyzed by immunohistochemistry. RESULTS: A significant association was observed between tumor size ≥100 g and lower expression levels of the BCL2 (P=0.03) and TNF (P=0.05) genes; between stage IV and lower expression levels of CASP3 (P=0.008), CASP9 (P=0.02), BCL2 (P=0.002), TNF (P=0.05), and NFKB (P=0.03); Weiss score ≥3 and lower expression of TNF (P=0.01); unfavorable event and higher expression values of CASP9 (P=0.01) and lower values of TNF (P=0.02); and death and lower expression of BCL2 (P=0.04). Underexpression of TNF was associated with lower event-free survival in uni- and multivariate analyses (P<0.01). Similar results were observed when patients with Weiss score <3 were excluded. CONCLUSION: This study supports the participation of apoptosis-related genes in the biology and prognosis of childhood ACT and suggests the complex role of these genes in the pathogenesis of this tumor.

Topoisomerase 2 alpha: a real predictor of anthracycline efficacy?

Anthracyclines are frequently used in the adjuvant setting for breast cancer treatment since it is considered that anthracycline-based chemotherapy treatment benefits breast cancer patients. Nonetheless, these drugs are associated with severe side effects and predictive factors, for sensitivity to anthracyclines, are warranted in clinical practice. Topoisomerase 2 alpha (TOP2A) is considered to be the molecular target of these drugs. The potential predictive value of TOP2A amplification and overexpression has been extensively studied in breast cancer patients treated with anthracyclines. However, results are not conclusive. In this paper, we review some of the published studies addressing the predictive value of TOP2A as well as the cellular functions of this enzyme and its status in breast cancer tissue.

MPL immunohistochemical expression as a novel marker for essential thrombocythemia and primary myelofibrosis differential diagnosis.

To evaluate the grading of fibrosis and immunohistochemical expression of MPL in bone marrow biopsies of ET and PMF. Fibrosis in bone marrow biopsies (BMBs) was evaluated according to the European Consensus for grading of fibrosis, according to reticulin proliferation. Immunohistochemical analysis was performed in samples from 18 ET and 38 PMF patients: 19 were classified as pre-fibrotic and 19 were classified as fibrotic according to the World Health Organization (WHO) criteria, by means of the MPL antibody. Six bone marrow donors' biopsies were used as controls. Average reticulin (p<0.003) and MPL (p<0.008) values differed significantly between the ET group and the pre-fibrotic stage PMF group. The MPL immunohistochemical expression may represent a new marker for differential diagnosis between ET and pre-fibrotic stage PMF.

Validation of cofilin-1 as a biomarker in non-small cell lung cancer: application of quantitative method in a retrospective cohort.

PURPOSE: Cofilin is a cytoskeletal protein whose overexpression has been associated with aggressiveness in several types of malignancies. Here, we established and optimized a simple semi-quantitative immunohistochemistry (SQ-IHC) method for cofilin quantification in tumor biopsies, and applied it in a retrospective cohort of NSCLC patients aiming at validating the use of cofilin-1 as a prognostic biomarker. METHODS: The SQ-IHC method for cofilin-1 quantification was established and applied in a NSCLC cohort. An archival collection of biopsies from 50 patients with clinicopathological information and 5 years follow-up was accessed. Association between cofilin-1 immunocontent and clinical outcome was assessed using standard Kaplan-Meier mortality curves and the log-rank test. To evaluate the robustness of our findings, three different partitional clustering strategies were used to stratify patients into two groups according to the biomarker expression level (hierarchical clustering, Kmeans and median cutoff). RESULTS: In all the three different partitional clustering we used, survival analysis showed that patient with high cofilin-1 immunocontent had a lower overall survival rate (P < 0.05), and could be used to discriminate between good and bad prognosis. No other correlation was found when the variables age, sex or histological type were tested in association with patients outcome or with cofilin immunocontent. CONCLUSIONS: Our method showed good sensitivity/specificity to indicate the outcome of patients according to their cofilin immunocontent in biological samples. Its application in a retrospective cohort and the results presented here are an important step toward the validation process of cofilin-1 as a prognostic biomarker.

Survivin as a predictive biomarker of complete pathologic response to neoadjuvant chemotherapy in patients with stage II and stage III breast cancer.

INTRODUCTION: Predictive biomarkers of response to neoadjuvant chemotherapy in patients with breast cancer are needed to better characterize tumors and enable more tailored therapies. METHODS: The expression levels of survivin, BCL-2, cyclin D1, ETS1, and PDEF in tumor samples obtained in the diagnostic biopsies of patients undergoing neoadjuvant chemotherapy for stage II and stage III disease were evaluated by immunohistochemistry (IHC). The mean expression score (range, 0-15) obtained by 3 different pathologists was used for analysis and correlated with complete pathologic response (pCR) and survival by standard univariate and multivariate methods. RESULTS: Forty-five female patients were included in this study and received preoperative standard anthracycline/taxane-based chemotherapy. The median age at diagnosis was 49 years (range, 25-70 years). Three patients (7.1%) achieved pCR. The mean expression score of survivin in the diagnostic biopsies was significantly higher (P = .01) in patients with pCR (9.3) than in those without (3.4). There was no significant association with pCR for the other biologic markers analyzed nor was there correlation with prognosis. Survivin levels were not associated with age, tumor grade, clinical stage, or receptor status. CONCLUSION: High expression levels of survivin in the primary tumor may be used as a potential predictive biomarker of pCR to neoadjuvant chemotherapy in patients with stage II and stage III breast cancer.

Molecular targets for therapeutic interventions in human papillomavirus-related cancers (review).

The infection by the human papillomavirus (HPV) is the origin of several cancers around the world. In some areas of Brazil, cervical carcinoma is still the cancer with the highest incidence among women. After epithelial cell transformation by HPV, several molecular events are observed, resulting in the malignant phenotype. In this review we discuss potential molecular targets for therapeutic interventions in human HPV-related carcinomas, with emphasis on cervical cancer, based on the alterations observed in the signaling transduction pathways caused by HPV infection. With a special attention to tyrosine kinase receptors, and other kinases involved in signal transduction and angiogenesis, these pathological alterations are evaluated as novel targets for anticancer therapies in HPV-related carcinomas.

Effects of THBS3, SPARC and SPP1 expression on biological behavior and survival in patients with osteosarcoma.

BACKGROUND: Osteosarcoma is a very aggressive tumor with a propensity to metastasize and invade surrounding tissue. Identification of the molecular determinants of invasion and metastatic potential may guide the development of a rational strategy for devising specific therapies that target the pathways leading to osteosarcoma. METHODS: In this study, we used pathway-focused low density expression cDNA arrays to screen for candidate genes related to tumor progression. Expression patterns of the selected genes were validated by real time PCR on osteosarcoma patient tumor samples and correlated with clinical and pathological data. RESULTS: THBS3, SPARC and SPP1 were identified as genes differentially expressed in osteosarcoma. In particular, THBS3 was expressed at significantly high levels (p = 0.0001) in biopsies from patients with metastasis at diagnosis, which is a predictor of worse overall survival, event-free survival and relapse free survival at diagnosis. After chemotherapy, patients with tumors over-expressing THBS3 have worse relapse free survival. High SPARC expression was found in 51/55 (96.3%) osteosarcoma samples derived from 43 patients, and correlated with the worst event-free survival (p = 0.03) and relapse free survival (p = 0.07). Overexpression of SPP1 was found in 47 of 53 (89%) osteosarcomas correlating with better overall survival, event-free survival and relapse free survival at diagnosis. CONCLUSION: In this study three genes were identified with pattern of differential gene expression associated with a phenotypic role in metastasis and invasion. Interestingly all encode for proteins involved in extracellular remodeling suggesting potential roles in osteosarcoma progression. This is the first report on the THBS3 gene working as a stimulator of tumor progression. Higher levels of THBS3 maintain the capacity of angiogenesis. High levels of SPARC are not required for tumor progression but are necessary for tumor growth and maintenance. SPP1 is not necessary for tumor progression in osteosarcoma and may be associated with inflammatory response and bone remodeling, functioning as a good biomarker.

Islet Neogenesis Associated Protein (INGAP) modulates gene expression in cultured neonatal rat islets.

The Islet Neogenesis Associated Protein (INGAP) increases pancreatic beta-cell mass and potentiates glucose-induced insulin secretion. We currently studied the effects of a pentadecapeptide having the 104-118 amino acid sequence of INGAP (INGAP-PP) on insulin secretion and on transcript profile expression in 4-day-cultured normal pancreatic neonatal rat islets. Islets cultured with INGAP-PP released significantly more insulin in response to 2.8 and 16.7 mM glucose than those cultured without the peptide. The macroarray analysis showed that 210 out of 2352 genes spotted in the nylon membranes were up-regulated while only 4 were down-regulated by INGAP-PP-treatment. The main categories of genes modified by INGAP-PP included several related with islet metabolism, insulin secretion mechanism, beta-cell mass and islet neogenesis. RT-PCR confirmed the macroarray results for ten selected genes involved in growing, maturation, maintenance of pancreatic islet-cells, and exocytosis, i.e., Hepatocyte nuclear factor 3beta (HNF3beta), Upstream stimulatory factor 1 (USF1), K(+)-channel proteins (SUR1 and Kir6.2), PHAS-I protein, Insulin 1 gene, Glucagon gene, Mitogen-activated protein kinase 1 (MAP3K1), Amylin (IAPP), and SNAP-25. INGAP-PP also stimulated PDX-1 expression. The expression of three transcripts (HNF3beta, SUR1, and SNAP-25) was confirmed by Western blotting for the corresponding proteins. In conclusion, our results show that INGAP-PP enhances specifically the secretion of insulin and the transcription of several islet genes, many of them directly or indirectly involved in the control of islet metabolism, beta-cell mass and islet neogenesis. These results, together with other previously reported, strongly indicate an important role of INGAP-PP, and possibly of INGAP, in the regulation of islet function and development.

O PSA como marcador tumoral é confiável? / PSA as tumor marker is reliable?

Considerado como um dos melhores marcadores tumorais, o antígeno prostático específico (PSA) é largamente utilizado. Valores acima de 4,ng/ml podem significar câncer de próstata (CaP). No entanto, doenças benignas podem alterar o seu valor e o câncer de próstata pode apresentar-se sem alterá-lo. O exame digital da próstata (EDP) e a dosagem de PSA são as melhores formas de diagnosticar e acompanhar os pacientes com mais de 40 anos.

One of the best tumors markers ever known, the prostate-specific antigen (PSA) is well advantage today. Values above 4.ng/ml can demonstrate prostate cancer. Although benign diseases would change the values of PSA and prostate cancers would not. Digital prostate exam (DPE) and PSA are the best way to diagnostic and watch men with over 40 years.

Dosimetria interna de radioinmunoterapia: consideraciones generales / Radioimmunotherapy internal dosimetry: general considerations

La Radioinmunoterapia ha atraído rápidamente el interés como modalidad potencial en el tratamiento del cáncer. Este presente trabajo revisa varios aspectos dosimétricos que involucran la efectividad de la técnica, así como, los procedimientos empleados en la obtención de la información dosimétrica, el tipo de radionucleido seleccionado, las limitaciones y posibilidades de los métodos de estimación dosimétrica; y proporciona un estudio detallado sobre los modelos radiobiológicos que con potencialidad pueden ser utilizados en la prescripción de la dosis en un sistema de planificación que permita establecer una relación dosis/respuesta del tratamiento(AU)

Radioimmunotherapy has a growing interest as a new potential modality for cancer treatment. In this paper several aspects are discussed: effectiveness of radioimmunotherapy, the procedures to get dosimetric information, the appropriate radionucleide and the possibilities and limitations that dosimetric estimation methods offer. A detailed study about radiobiological models which can be used for dose prescription is also presented(AU)

Dosimetria interna de radioinmunoterapia: consideraciones generales / Radioimmunotherapy internal dosimetry: general considerations

La Radioinmunoterapia ha atraído rápidamente el interés como modalidad potencial en el tratamiento del cáncer. Este presente trabajo revisa varios aspectos dosimétricos que involucran la efectividad de la técnica, así como, los procedimientos empleados en la obtención de la información dosimétrica, el tipo de radionucleido seleccionado, las limitaciones y posibilidades de los métodos de estimación dosimétrica; y proporciona un estudio detallado sobre los modelos radiobiológicos que con potencialidad pueden ser utilizados en la prescripción de la dosis en un sistema de planificación que permita establecer una relación dosis/respuesta del tratamiento