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1.
Int J Mol Sci ; 25(8)2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38673897

RESUMO

Pancreatic cancer, most frequently as ductal adenocarcinoma (PDAC), is the third leading cause of cancer death. Clear-cell primary adenocarcinoma of the pancreas (CCCP) is a rare, aggressive, still poorly characterized subtype of PDAC. We report here a case of a 65-year-old male presenting with pancreatic neoplasia. A histochemical examination of the tumor showed large cells with clear and abundant intracytoplasmic vacuoles. The clear-cell foamy appearance was not related to the hyperproduction of mucins. Ultrastructural characterization with transmission electron microscopy revealed the massive presence of mitochondria in the clear-cell cytoplasm. The mitochondria showed disordered cristae and various degrees of loss of structural integrity. Immunohistochemistry staining for NADH dehydrogenase [ubiquinone] 1 alpha subcomplex, 4-like 2 (NDUFA4L2) proved specifically negative for the clear-cell tumor. Our ultrastructural and molecular data indicate that the clear-cell nature in CCCP is linked to the accumulation of disrupted mitochondria. We propose that this may impact on the origin and progression of this PDAC subtype.


Assuntos
Mitocôndrias , Neoplasias Pancreáticas , Humanos , Masculino , Idoso , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/ultraestrutura , Neoplasias Pancreáticas/metabolismo , Mitocôndrias/ultraestrutura , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Adenocarcinoma de Células Claras/patologia , Adenocarcinoma de Células Claras/ultraestrutura , Adenocarcinoma de Células Claras/metabolismo , Microscopia Eletrônica de Transmissão , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/ultraestrutura , Carcinoma Ductal Pancreático/metabolismo , Imuno-Histoquímica
2.
Int J Mol Sci ; 24(16)2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37628814

RESUMO

Pancreatic cancer (PC) is the seventh leading cause of cancer-related death. PC incidence has continued to increase by about 1% each year in both men and women. Although the 5-year relative survival rate of PC has increased from 3% to 12%, it is still the lowest among cancers. Hence, novel therapeutic strategies are urgently needed. Challenges in PC-targeted therapeutic strategies stem from the high PC heterogeneity and from the poorly understood interplay between cancer cells and the surrounding microenvironment. Signaling pathways that drive PC cell growth have been the subject of intense scrutiny and interest has been attracted by necroptosis, a distinct type of programmed cell death. In this review, we provide a historical background on necroptosis and a detailed analysis of the ongoing debate on the role of necroptosis in PC malignant progression.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Masculino , Feminino , Humanos , Necroptose , Apoptose , Microambiente Tumoral , Neoplasias Pancreáticas
3.
Int J Mol Sci ; 23(1)2021 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-35008832

RESUMO

Chimeric antigen receptor (CAR) therapy is based on patient blood-derived T cells and natural killer cells, which are engineered in vitro to recognize a target antigen in cancer cells. Most CAR-T recognize target antigens through immunoglobulin antigen-binding regions. Hence, CAR-T cells do not require the major histocompatibility complex presentation of a target peptide. CAR-T therapy has been tremendously successful in the treatment of leukemias. On the other hand, the clinical efficacy of CAR-T cells is rarely detected against solid tumors. CAR-T-cell therapy of cancer faces many hurdles, starting from the administration of engineered cells, wherein CAR-T cells must encounter the correct chemotactic signals to traffic to the tumor in sufficient numbers. Additional obstacles arise from the hostile environment that cancers provide to CAR-T cells. Intense efforts have gone into tackling these pitfalls. However, we argue that some CAR-engineering strategies may risk missing the bigger picture, i.e., that a successful CAR-T-cell therapy must efficiently intertwine with the complex and heterogeneous responses that the body has already mounted against the tumor. Recent findings lend support to this model.


Assuntos
Imunoterapia Adotiva , Neoplasias/imunologia , Animais , Antígenos de Neoplasias/imunologia , Humanos , Terapia de Imunossupressão , Modelos Biológicos , Neoplasias/patologia , Receptores de Antígenos Quiméricos/imunologia
4.
BMC Cancer ; 19(1): 747, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-31362705

RESUMO

BACKGROUND: Phospholipase Cγ1 (PLCγ1) is highly expressed in human tumours. Our previous studies reported that both stable and inducible PLCγ1 down-regulation can inhibit formation of breast-cancer-derived experimental lung metastasis. Further, high expression of PLCγ1 and its constitutively activated forms (i.e., PLCγ1-pY1253, PLCγ1-pY783) is associated with worse clinical outcome in terms of incidence of distant metastases, but not of local relapse in T1-T2, N0 breast cancer patients. METHODS: In the present retrospective study, we analysed the prognostic role of PLCγ1 in early breast cancer patients stratified according to the St. Gallen criteria and to their menopausal status. PLCγ1-pY1253 and PLCγ1-pY783 protein expression levels were determined by immunohistochemistry on tissue microarrays, and were correlated with patients' clinical data, using univariate and multivariate statistical analyses. RESULTS: In our series, the prognostic value of PLCγ1 overexpression was restricted to Luminal type tumours. From multivariate analyses, pY1253-PLCγ1High was an independent prognostic factor only in postmenopausal patients with Luminal-B tumours (hazard ratio [HR], 2.4; 95% confidence interval [CI], 1.1-5.3; P = 0.034). Conversely, PLCγ1-pY783High was a remarkably strong risk factor (HR, 20.1; 95% CI, 2.2-178.4; P = 0.003) for pre/perimenopausal patients with Luminal-A tumours. CONCLUSIONS: PLCγ1 overexpression is a strong predictive surrogate marker of development of metastases in early Luminal-A and -B breast cancer patients, being able to discriminate patients with high and low risk of metastases. Therefore, targeting the PLCγ1 pathway can be considered of potential benefit for prevention of metastatic disease.


Assuntos
Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Fosfolipase C gama/metabolismo , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Idoso , Biomarcadores Tumorais/metabolismo , Feminino , Seguimentos , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Antígeno Ki-67/metabolismo , Menopausa/fisiologia , Pessoa de Meia-Idade , Análise Multivariada , Metástase Neoplásica , Recidiva Local de Neoplasia , Estadiamento de Neoplasias , Fosforilação , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos
5.
BMC Cancer ; 16: 649, 2016 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-27538498

RESUMO

BACKGROUND: Traditional prognostic indicators of breast cancer, i.e. lymph node diffusion, tumor size, grading and estrogen receptor expression, are inadequate predictors of metastatic relapse. Thus, additional prognostic parameters appear urgently needed. Individual oncogenic determinants have largely failed in this endeavour. Only a few individual tumor growth drivers, e.g. mutated p53, Her-2, E-cadherin, Trops, did reach some prognostic/predictive power in clinical settings. As multiple factors are required to drive solid tumor progression, clusters of such determinants were expected to become stronger indicators of tumor aggressiveness and malignant progression than individual parameters. To identify such prognostic clusters, we went on to coordinately analyse molecular and histopathological determinants of tumor progression of post-menopausal breast cancers in the framework of a multi-institutional case series/case-control study. METHODS: A multi-institutional series of 217 breast cancer cases was analyzed. Twenty six cases (12 %) showed disease relapse during follow-up. Relapsed cases were matched with a set of control patients by tumor diameter, pathological stage, tumor histotype, age, hormone receptors and grading. Histopathological and molecular determinants of tumor development and aggressiveness were then analyzed in relapsed versus non-relapsed cases. Stepwise analyses and model structure fitness assessments were carried out to identify clusters of molecular alterations with differential impact on metastatic relapse. RESULTS: p53, Bcl-2 and cathepsin D were shown to be coordinately associated with unique levels of relative risk for disease relapse. As many Ras downstream targets, among them matrix metalloproteases, are synergistically upregulated by mutated p53, whole-exon sequence analyses were performed for TP53, Ki-RAS and Ha-RAS, and findings were correlated with clinical phenotypes. Notably, TP53 insertion/deletion mutations were only detected in relapsed cases. Correspondingly, Ha-RAS missense oncogenic mutations were only found in a subgroup of relapsing tumors. CONCLUSIONS: We have identified clusters of specific molecular alterations that greatly improve prognostic assessment with respect to singularly-analysed indicators. The combined analysis of these multiple tumor-relapse risk factors promises to become a powerful approach to identify patients subgroups with unfavourable disease outcome.


Assuntos
Neoplasias da Mama/patologia , Catepsina D/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteína Supressora de Tumor p53/genética , Idoso , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Estudos de Casos e Controles , Feminino , Redes Reguladoras de Genes , Humanos , Pessoa de Meia-Idade , Mutação , Prognóstico , Recidiva , Análise de Sequência de DNA
6.
Hum Genomics ; 9: 17, 2015 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-26216216

RESUMO

Genome-wide association studies of complex physiological traits and diseases consistently found that associated genetic factors, such as allelic polymorphisms or DNA mutations, only explained a minority of the expected heritable fraction. This discrepancy is known as "missing heritability", and its underlying factors and molecular mechanisms are not established. Epigenetic programs may account for a significant fraction of the "missing heritability." Epigenetic modifications, such as DNA methylation and chromatin assembly states, reflect the high plasticity of the genome and contribute to stably alter gene expression without modifying genomic DNA sequences. Consistent components of complex traits, such as those linked to human stature/height, fertility, and food metabolism or to hereditary defects, have been shown to respond to environmental or nutritional condition and to be epigenetically inherited. The knowledge acquired from epigenetic genome reprogramming during development, stem cell differentiation/de-differentiation, and model organisms is today shedding light on the mechanisms of (a) mitotic inheritance of epigenetic traits from cell to cell, (b) meiotic epigenetic inheritance from generation to generation, and (c) true transgenerational inheritance. Such mechanisms have been shown to include incomplete erasure of DNA methylation, parental effects, transmission of distinct RNA types (mRNA, non-coding RNA, miRNA, siRNA, piRNA), and persistence of subsets of histone marks.


Assuntos
Diferenciação Celular/genética , Reprogramação Celular/genética , Metilação de DNA/genética , Epigênese Genética , Montagem e Desmontagem da Cromatina/genética , Regulação da Expressão Gênica/genética , Estudo de Associação Genômica Ampla , Humanos , Meiose/genética , Mitose/genética
7.
BMC Cancer ; 15: 417, 2015 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-25986046

RESUMO

BACKGROUND: DNA methylation regulates gene expression, through the inhibition/activation of gene transcription of methylated/unmethylated genes. Hence, DNA methylation profiling can capture pivotal features of gene expression in cancer tissues from patients at the time of diagnosis. In this work, we analyzed a breast cancer case series, to identify DNA methylation determinants of metastatic versus non-metastatic tumors. METHODS: CpG-island methylation was evaluated on a 56-gene cancer-specific biomarker microarray in metastatic versus non-metastatic breast cancers in a multi-institutional case series of 123 breast cancer patients. Global statistical modeling and unsupervised hierarchical clustering were applied to identify a multi-gene binary classifier with high sensitivity and specificity. Network analysis was utilized to quantify the connectivity of the identified genes. RESULTS: Seven genes (BRCA1, DAPK1, MSH2, CDKN2A, PGR, PRKCDBP, RANKL) were found informative for prognosis of metastatic diffusion and were used to calculate classifier accuracy versus the entire data-set. Individual-gene performances showed sensitivities of 63-79 %, 53-84 % specificities, positive predictive values of 59-83 % and negative predictive values of 63-80 %. When modelled together, these seven genes reached a sensitivity of 93 %, 100 % specificity, a positive predictive value of 100 % and a negative predictive value of 93 %, with high statistical power. Unsupervised hierarchical clustering independently confirmed these findings, in close agreement with the accuracy measurements. Network analyses indicated tight interrelationship between the identified genes, suggesting this to be a functionally-coordinated module, linked to breast cancer progression. CONCLUSIONS: Our findings identify CpG-island methylation profiles with deep impact on clinical outcome, paving the way for use as novel prognostic assays in clinical settings.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Ilhas de CpG , Metilação de DNA , Epigênese Genética , Epigenômica , Biomarcadores Tumorais , Análise por Conglomerados , Progressão da Doença , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Metástase Neoplásica , Prognóstico , Sensibilidade e Especificidade
8.
Biochim Biophys Acta ; 1836(1): 27-41, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23428607

RESUMO

Body development requires the ability to control cell proliferation and metabolism, together with selective 'invasive' cell migration for organogenesis. These requirements are shared with cancer. Human height-associated loci have been recently identified by genome-wide SNP-association studies. Strikingly, most of the more than 100 genes found associated to height appear linked to neoplastic growth, and impose a higher risk for cancer. Height-associated genes drive the HH/PTCH and BMP/TGFß pathways, with p53, c-Myc, ERα, HNF4A and SMADs as central network nodes. Genetic analysis of body-size-affecting diseases and evidence from genetically-modified animals support this model. The finding that cancer is deeply linked to normal, body-plan master genes may profoundly affect current paradigms on tumor development.


Assuntos
Estatura/genética , Proteínas de Neoplasias/genética , Neoplasias/etiologia , Humanos
10.
iScience ; 27(9): 110658, 2024 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-39246444

RESUMO

Intra-tumor heterogeneity, i.e., the presence of diverse cell types and subpopulations within tumors, presents a significant obstacle in cancer treatment due to its negative consequences for resistance to therapy and disease recurrence. However, the mechanisms that underlie intra-tumor heterogeneity and result in the plethora of different cancer cells within a single lesion remain poorly understood. Here, we leverage the SW480 cell line as a model system to investigate the molecular and functional diversity of colon cancer cells. Through a combination of fluorescence-activated cell sorting (FACS) analysis and transcriptomic profiling, we identified three distinct subpopulations, namely resident cancer stem cells (rCSCs), migratory CSCs (mCSCs), and high-relapse cells (HRCs). These subpopulations show varying Wnt signaling levels and gene expression profiles mirroring their stem-like and functional properties. Examination of publicly available spatial transcriptomic data confirms the presence of these subpopulations in patient-derived cancers and reveals their distinct spatial distribution relative to the tumor microenvironment.

11.
Int J Cancer ; 132(5): 1022-31, 2013 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22847294

RESUMO

Phospholipase Cγ1 (PLCγ1) is highly expressed in several tumors. We have previously reported that both stable and inducible PLCγ1 down-regulation resulted in an almost complete inhibition of breast cancer-derived experimental lung metastasis formation. The aim of our study is to evaluate the association between the expression of PLCγ1 and of PLCγ1 phosphorylated at Tyr1253 (PLCγ1-pY1253) and at Tyr783 (PLCγ1-pY783) with the clinical outcome of patients with node negative, T1/T2 breast cancers. The study groups consisted of 292 (training set) and 122 (validation set) patients presenting with primary unilateral breast carcinoma (T1-T2), with no evidence of nodal involvement and distant metastases. PLCγ1, PLCγ1-pY1253 and PLCγ1-pY783 protein expression were assessed by immunohistochemistry on tissue microarrays and the results correlated with the clinical data using Kaplan-Meier curves and multivariate Cox regression analysis. Tumor cells while expressing variable proportions of cytoplasmic PLCγ1, express PLCγ1-pY1253 and PLCγ1-pY783 predominantly in the nucleus. High expression of PLCγ1, and of its activated forms, is associated with a worse clinical outcome in terms of incidence of distant metastases, and not of local relapse in T1-T2, N0 breast cancer patients undergone adjuvant chemotherapy. PLCγ1 over-expression appears to be a reliable predictive surrogate marker of development of metastases. Thus, targeting PLCγ1 pathways might represent a potential therapeutic approach for the prevention of metastatic disease in breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/enzimologia , Fosfolipase C gama/biossíntese , Idoso , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Quimioterapia Adjuvante , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Fosfolipase C gama/genética , Fosfolipase C gama/metabolismo , Fatores de Risco
12.
Front Oncol ; 13: 1151090, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37456256

RESUMO

The advent of high throughput DNA sequencing is providing massive amounts of tumor-associated mutation data. Implicit in these analyses is the assumption that, by acquiring a series of hallmark changes, normal cells evolve along a neoplastic path. However, the lack of correlation between cancer risk and global exposure to mutagenic factors provides arguments against this model. This suggested that additional, non-mutagenic factors are at work in cancer development. A candidate determinant is TROP2, that stands out for its expression in the majority of solid tumors in human, for its impact on the prognosis of most solid cancers and for its role as driver of cancer growth and metastatic diffusion, through overexpression as a wild-type form. The Trop-2 signaling network encompasses CREB1, Jun, NF-κB, Rb, STAT1 and STAT3, through induction of cyclin D1 and MAPK/ERK. Notably, Trop-2-driven pathways vastly overlap with those activated by most functionally relevant/most frequently mutated RAS and TP53, and are co-expressed in a large fraction of individual tumor cases, suggesting functional overlap. Mutated Ras was shown to synergize with the TROP2-CYCLIND1 mRNA chimera in transforming primary cells into tumorigenic ones. Genomic loss of TROP2 was found to promote carcinogenesis in squamous cell carcinomas through modulation of Src and mutated Ras pathways. DNA methylation and TP53 status were shown to cause genome instability and TROP gene amplification, together with Trop-2 protein overexpression. These findings suggest that mutagenic and the TROP2 non-mutagenic pathways deeply intertwine in driving transformed cell growth and malignant progression of solid cancers.

13.
Cancers (Basel) ; 15(14)2023 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-37509383

RESUMO

Trop-2 proteolytic processing in cancer cells exposes epitopes that were specifically targeted by the 2G10 antibody. We sought additional recognition of Trop-2 within difficult-to-reach, densely packed tumor sites. Trop-2 deletion mutants were employed in immunization and screening procedures, and these led to the recognition of a novel epitope in the N-terminal region of Trop-2, by the 2EF antibody. The 2EF mAb was shown to bind Trop-2 at cell-cell junctions in MCF-7 breast cancer cells, and in deeply seated sites in prostate cancer, that were inaccessible to benchmark anti-Trop-2 antibodies. The 2EF antibody was shown to inhibit the growth of HT29 colon tumor cells in vitro, with the highest activity at high cell density. In vivo, 2EF showed anticancer activity against SKOv3 ovarian, Colo205, HT29, HCT116 colon and DU-145 prostate tumors, with the highest impact on densely packed tumor sites, whereby 2EF outcompeted benchmark anti-Trop-2 antibodies. Given the different recognition modes of Trop-2 by 2EF and 2G10, we hypothesized the effective interaction of the two mAb in vivo. The 2EF mAb was indeed demonstrated to enhance the activity of 2G10 against tumor xenotransplants, opening novel avenues for Trop-2-targeted therapy. We humanized 2EF by state-of-the-art CDR grafting/re-modeling, yielding the Hu2EF for therapy of Trop-2-expressing tumors in patients.

14.
Front Genet ; 14: 1297367, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38250577

RESUMO

A phylogenetic conservation analysis of Trop-2 across vertebrate species showed a high degree of sequence conservation, permitting to explore multiple models as pre-clinical benchmarks. Sequence divergence and incomplete conservation of expression patterns were observed in mouse and rat. Primate Trop-2 sequences were found to be 95%-100% identical to the human sequence. Comparative three-dimension primate Trop-2 structures were obtained with AlphaFold and homology modeling. This revealed high structure conservation of Trop-2 (0.66 ProMod3 GMQE, 0.80-0.86 ± 0.05 QMEANDisCo scores), with conservative amino acid changes at variant sites. Primate TACSTD2/TROP2 cDNAs were cloned and transfectants for individual ORF were shown to be efficiently recognized by humanized anti-Trop-2 monoclonal antibodies (Hu2G10, Hu2EF). Immunohistochemistry analysis of Macaca mulatta (rhesus monkey) tissues showed Trop-2 expression patterns that closely followed those in human tissues. This led us to test Trop-2 targeting in vivo in Macaca fascicularis (cynomolgus monkey). Intravenously injected Hu2G10 and Hu2EF were well tolerated from 5 to 10 mg/kg. Neither neurological, respiratory, digestive, urinary symptoms, nor biochemical or hematological toxicities were detected during 28-day observation. Blood serum pharmacokinetic (PK) studies were conducted utilizing anti-idiotypic antibodies in capture-ELISA assays. Hu2G10 (t1/2 = 6.5 days) and Hu2EF (t1/2 = 5.5 days) were stable in plasma, and were detectable in the circulation up to 3 weeks after the infusion. These findings validate primates as reliable models for Hu2G10 and Hu2EF toxicity and PK, and support the use of these antibodies as next-generation anti-Trop-2 immunotherapy tools.

15.
Mol Cancer Ther ; 22(6): 790-804, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36921314

RESUMO

Next-generation Trop-2-targeted therapy against advanced cancers is hampered by expression of Trop-2 in normal tissues. We discovered that Trop-2 undergoes proteolytic activation by ADAM10 in cancer cells, leading to the exposure of a previously inaccessible protein groove flanked by two N-glycosylation sites. We designed a recognition strategy for this region, to drive selective cancer vulnerability in patients. Most undiscriminating anti-Trop-2 mAbs recognize a single immunodominant epitope. Hence, we removed it by deletion mutagenesis. Cancer-specific, glycosylation-prone mAbs were selected by ELISA, bio-layer interferometry, flow cytometry, confocal microscopy for differential binding to cleaved/activated, wild-type and glycosylation site-mutagenized Trop-2. The resulting 2G10 mAb family binds Trop-2-expressing cancer cells, but not Trop-2 on normal cells. We humanized 2G10 by state-of-the-art complementarity determining region grafting/re-modeling, yielding Hu2G10. This antibody binds cancer-specific, cleaved/activated Trop-2 with Kd < 10-12 mol/L, and uncleaved/wtTrop-2 in normal cells with Kd 3.16×10-8 mol/L, thus promising an unprecedented therapeutic index in patients. In vivo, Hu2G10 ablates growth of Trop-2-expressing breast, colon, prostate cancers, but shows no evidence of systemic toxicity, paving the way for a paradigm shift in Trop-2-targeted therapy.


Assuntos
Imunoconjugados , Neoplasias da Próstata , Masculino , Humanos , Antígenos de Neoplasias/genética , Anticorpos Monoclonais/farmacologia
16.
J Cancer ; 14(15): 2751-2758, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781086

RESUMO

Sex might influence prognosis in patients affected by colorectal cancer. We retrospectively studied a cohort of patients affected by metastatic colon cancer (mCC) stratified by sex and primary tumor location. RAS mutational status was also included in the analysis. Overall, 616 patients met the eligibility criteria, 261 women and 355 men. Neither gender, nor RAS mutational status influenced overall survival (OS) in the entire population. As expected, patients with right-sided colon cancer (RCC) had a significant shorter OS compared to those with left-sided colon cancer (LCC) (21.3 vs 33.1 months, p= 0.002). When the analysis was performed stratifying for gender, RCC retained worse prognosis among men (OS 20.5 vs 33.9 months, p= 0.008), but not among women (p= 0.132). Similarly, the presence of RAS mutations had no prognostic effect in women, but was significantly associate with shorter survival in men (OS 29.5 vs 33.7 months, p= 0.046). In addition, when comparing clinical outcome of women or men according to sidedness and RAS mutational status, RCC was associated with dismal prognosis only in men with RAS mutated tumor (OS 17.2 vs 32.3 months, p= 0.008). Our study highlights the importance of gender in the outcome of patients with mCC.

17.
J Cell Physiol ; 227(11): 3670-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22378065

RESUMO

Trop-2 is a transmembrane glycoprotein upregulated in several human carcinomas, including prostate cancer (PrCa). Trop-2 has been suggested to regulate cell-cell adhesion, given its high homology with the other member of the Trop family, Trop-1/EpCAM, and its ability to bind the tight junction proteins claudin-1 and claudin-7. However, a role for Trop-2 in cell adhesion to the extracellular matrix has never been postulated. Here, we show for the first time that Trop-2 expression in PrCa cells correlates with their aggressiveness. Using either shRNA-mediated silencing of Trop-2 in cells that endogenously express it, or ectopic expression of Trop-2 in cells that do not express it, we show that Trop-2 inhibits PrCa cell adhesion to fibronectin (FN). In contrast, expression of another transmembrane receptor, α(v) ß(5) integrin, does not affect cell adhesion to this ligand. We find that Trop-2 does not modulate either protein or activation levels of the prominent FN receptors, ß(1) integrins, but acts through increasing ß(1) association with the adaptor molecule RACK1 and redistribution of RACK1 to the cell membrane. As a result of Trop-2 expression, we also observe activation of Src and FAK, known to occur upon ß(1) -RACK1 interaction. These enhanced Src and FAK activities are not mediated by changes in either the activity of IGF-IR, which is known to bind RACK1, or IGF-IR's ability to associate with ß(1) integrins. In summary, our data demonstrate that the transmembrane receptor Trop-2 is a regulator of PrCa cell adhesion to FN through activation of the ß(1) integrin-RACK1-FAK-Src signaling axis.


Assuntos
Antígenos de Neoplasias , Moléculas de Adesão Celular , Adesão Celular/genética , Proteínas de Ligação ao GTP/metabolismo , Integrina beta1/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias da Próstata , Receptores de Superfície Celular/metabolismo , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/metabolismo , Moléculas de Adesão Celular/antagonistas & inibidores , Moléculas de Adesão Celular/genética , Moléculas de Adesão Celular/metabolismo , Linhagem Celular Tumoral , Molécula de Adesão da Célula Epitelial , Fibronectinas/metabolismo , Quinase 1 de Adesão Focal/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia , Receptores de Quinase C Ativada , Transdução de Sinais , Quinases da Família src/metabolismo
18.
Jpn J Clin Oncol ; 42(12): 1128-37, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23072840

RESUMO

OBJECTIVE: Trop-1/Ep-CAM modulates growth and survival of transformed cells, and it is highly expressed in most carcinomas including breast cancer. Only membranous staining is typically considered in evaluating Trop-1/epithelial cell adhesion molecule (Ep-CAM) expression in tumor cells. However, there is evidence of retention of Trop-1/Ep-CAM, as functionally incompetent molecules, in intra-cytoplasmic vesicles. Hence, we investigated whether cytoplasmic immunostaining may have an independent clinical significance with respect to membranous staining. METHODS: Membranous and cytoplasmic Trop-1/Ep-CAM expression was immunohistochemically investigated in 642 unilateral breast cancers from patients with a 99-month median follow-up. Multiple correspondence analysis was used to investigate the association between Trop-1/Ep-CAM and other biological variables. The impact of Trop-1/Ep-CAM expression on the patient's outcome was evaluated as event-free survival by the Kaplan-Meier method and proportional hazard Cox model. RESULTS: While tumors with intermediate/strong membranous staining were mostly associated with concomitant cytoplasmic Trop-1/Ep-CAM expression (97%), tumors with weak-to-nil membranous staining showed intermediate/high cytoplasmic expression in 23% of cases. Cytoplasmic overexpression was associated with a favorable outcome, especially in node-positive patients, regardless of the adjuvant therapy received. CONCLUSION: Trop-1/Ep-CAM expression may have different clinical implications according to its subcellular localization.


Assuntos
Antígenos de Neoplasias/metabolismo , Neoplasias da Mama/metabolismo , Moléculas de Adesão Celular/metabolismo , Citoplasma/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Intervalo Livre de Doença , Molécula de Adesão da Célula Epitelial , Feminino , Humanos , Imuno-Histoquímica , Itália/epidemiologia , Estimativa de Kaplan-Meier , Metástase Linfática , Pessoa de Meia-Idade , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise Serial de Tecidos
19.
NAR Genom Bioinform ; 4(1): lqac008, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35261972

RESUMO

The recognition code between transcription factor (TF) amino acids and DNA bases remains poorly understood. Here, the determinants of TF amino acid-DNA base binding selectivity were identified through the analysis of crystals of TF-DNA complexes. Selective, high-frequency interactions were identified for the vast majority of amino acid side chains ('structural code'). DNA binding specificities were then independently assessed by meta-analysis of random-mutagenesis studies of Zn finger-target DNA sequences. Selective, high-frequency interactions were identified for the majority of mutagenized residues ('mutagenesis code'). The structural code and the mutagenesis code were shown to match to a striking level of accuracy (P = 3.1 × 10-33), suggesting the identification of fundamental rules of TF binding to DNA bases. Additional insight was gained by showing a geometry-dictated choice among DNA-binding TF residues with overlapping specificity. These findings indicate the existence of a DNA recognition mode whereby the physical-chemical characteristics of the interacting residues play a deterministic role. The discovery of this DNA recognition code advances our knowledge on fundamental features of regulation of gene expression and is expected to pave the way for integration with higher-order complexity approaches.

20.
Cancers (Basel) ; 14(19)2022 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-36230592

RESUMO

Advances in the management of gastric cancer have improved patient survival in the last decade. Nonetheless, the number of patients relapsing and dying after a diagnosis of localized gastric cancer is still too high, even in early stages (10% in stage I). Adjuvant systemic chemotherapy has been proven to significantly improve outcomes. In the present article we have critically reviewed the clinical trials that guide the current clinical practice in the adjuvant treatment of patients affected by resectable gastric cancer, focusing on the different approaches worldwide, i.e., adjuvant chemotherapy, adjuvant chemoradiotherapy, and perioperative chemotherapy. We also delineate the clinical-pathological characteristics that are commonly taken into account to identify patients at a higher risk of recurrence and requiring adjuvant chemotherapy, and also describe novel biomarkers and therapeutic agents that might allow personalization of the treatment.

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