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1.
Rev Invest Clin ; 72(5)2020 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-33057321

RESUMEN

BACKGROUND: The incidence of renal cell carcinoma (RCC) is increasing globally due to an aging population and widespread use of imaging studies. OBJECTIVE: The aim of this study was to describe the characteristics and perioperative outcomes of RCC surgery in very elderly patients (VEP), ≥ 75 years of age. METHODS: This is a retrospective comparative study of 3656 patients who underwent the treatment for RCC from 1990 to 2015 in 28 centers from eight Latin American countries. We compared baseline characteristics as well as clinical and perioperative outcomes according to age groups (less than 75 vs. ≥75 years). Surgical complications were classified with the Clavien-Dindo score. We performed logistic regression analysis to identify factors associated with perioperative complications. RESULTS: There were 410 VEP patients (11.2%). On bivariate analysis, VEP had a lower body mass index (p less than 0.01) and higher ASA score (ASA > 2 in 26.3% vs. 12.4%, p < 0.01). There was no difference in performance status and clinical stage between the study groups. There were no differences in surgical margins, estimated blood loss (EBL), complication, and mortality rates (1.3% vs. 0.4%, p = 0.17). On multivariate regression analysis, age ≥75 years (odds ratio [OR] 2.33, p less than 0.01), EBL ≥ 500 cc (OR 3.34, p less than 0.01), and > pT2 stage (OR 1.63, p = 0.04) were independently associated with perioperative complications. CONCLUSIONS: Surgical resection of RCC was safe and successful in VEP. Age ≥75 years was independently associated with 30-day perioperative complications. However, the vast majority were low-grade complications. Age alone should not guide decision-making in these patients, and treatment must be tailored according to performance status and severity of comorbidities.

2.
Int J Cancer ; 138(7): 1719-31, 2016 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-26519949

RESUMEN

Trypanosoma cruzi, the protozoan parasite that causes Chagas' disease, has anticancer effects mediated, at least in part, by parasite-derived products which inhibit growth of tumor cells. We investigated whether immunity to T. cruzi antigens could induce antitumor activity, using two rat models which reproduce human carcinogenesis: colon cancer induced by 1,2-dimethylhydrazine (DMH), and mammary cancer induced by N-nitroso-N-methylurea (NMU). We found that vaccination with T. cruzi epimastigote lysates strongly inhibits tumor development in both animal models. Rats immunized with T. cruzi antigens induce activation of both CD4(+) and CD8(+) T cells and splenocytes from these animals showed higher cytotoxic responses against tumors as compared to rats receiving adjuvant alone. Tumor-associated immune responses included increasing number of CD11b/c(+) His48(-) MHC II(+) cells corresponding to macrophages and/or dendritic cells, which exhibited augmented NADPH-oxidase activity. We also found that T. cruzi lysate vaccination developed antibodies specific for colon and mammary rat cancer cells, which were capable of mediating antibody-dependent cellular cytotoxicity (ADCC) in vitro. Anti-T. cruzi antibodies cross-reacted with human colon and breast cancer cell lines and recognized 41/60 (68%) colon cancer and 38/63 (60%) breast cancer samples in a series of 123 human tumors. Our results suggest that T. cruzi antigens can evoke an integrated antitumor response involving both the cellular and humoral components of the immune response and provide novel insights into the understanding of the intricate relationship between parasite infection and tumor growth.


Asunto(s)
Antígenos de Protozoos/inmunología , Neoplasias de la Mama/inmunología , Vacunas contra el Cáncer/inmunología , Neoplasias del Colon/inmunología , Trypanosoma cruzi/inmunología , 1,2-Dimetilhidrazina/toxicidad , Animales , Anticuerpos Antiprotozoarios/sangre , Anticuerpos Antiprotozoarios/inmunología , Citotoxicidad Celular Dependiente de Anticuerpos/inmunología , Neoplasias de la Mama/inducido químicamente , Carcinógenos/toxicidad , Línea Celular Tumoral , Neoplasias del Colon/inducido químicamente , Reacciones Cruzadas , Modelos Animales de Enfermedad , Femenino , Citometría de Flujo , Humanos , Inmunohistoquímica , Metilnitrosourea/toxicidad , Ratas , Ratas Wistar
3.
Rev Med Chil ; 144(10): 1305-1318, 2016 Oct.
Artículo en Español | MEDLINE | ID: mdl-28074986

RESUMEN

Pancreatic cancer is a malignancy of great impact in developed countries and is having an increasing impact in Latin America. Incidence and mortality rates are similar for this cancer. This is an important reason to offer to the patients the best treatments available. During the Latin American Symposium of Gastroenterology Oncology (SLAGO) held in Viña del Mar, Chile, in April 2015, a multidisciplinary group of specialists in the field met to discuss about this disease. The main conclusions of this meeting, where practitioners from most of Latin American countries participated, are listed in this consensus that seek to serve as a guide for better decision making for patients with pancreatic cancer in Latin America.


Asunto(s)
Adenocarcinoma/terapia , Manejo de la Enfermedad , Neoplasias Pancreáticas/terapia , Guías de Práctica Clínica como Asunto , Antimetabolitos Antineoplásicos/uso terapéutico , Quimioradioterapia , Conferencias de Consenso como Asunto , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapéutico , Humanos , América Latina , Gemcitabina
4.
Cancer Immunol Immunother ; 62(6): 1107-22, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23604173

RESUMEN

The Tn antigen (GalNAcα-O-Ser/Thr) is a well-established tumor-associated marker which represents a good target for the design of anti-tumor vaccines. Several studies have established that the binding of some anti-Tn antibodies could be affected by the density of Tn determinant or/and by the amino acid residues neighboring O-glycosylation sites. In the present study, using synthetic Tn-based vaccines, we have generated a panel of anti-Tn monoclonal antibodies. Analysis of their binding to various synthetic glycopeptides, modifying the amino acid carrier of the GalNAc(*) (Ser* vs Thr*), showed subtle differences in their fine specificities. We found that the recognition of these glycopeptides by some of these MAbs was strongly affected by the Tn backbone, such as a S*S*S* specific MAb (15G9) which failed to recognize a S*T*T* or a T*T*T* structure. Different binding patterns of these antibodies were also observed in FACS and Western blot analysis using three human cancer cell lines (MCF-7, LS174T and Jurkat). Importantly, an immunohistochemical analysis of human tumors (72 breast cancer and 44 colon cancer) showed the existence of different recognition profiles among the five antibodies evaluated, demonstrating that the aglyconic part of the Tn structure (Ser vs Thr) plays a key role in the anti-Tn specificity for breast and colon cancer detection. This new structural feature of the Tn antigen could be of important clinical value, notably due to the increasing interest of this antigen in anticancer vaccine design as well as for the development of anti-Tn antibodies for in vivo diagnostic and therapeutic strategies.


Asunto(s)
Anticuerpos Monoclonales/inmunología , Antígenos de Carbohidratos Asociados a Tumores/inmunología , Glicopéptidos/inmunología , Neoplasias/inmunología , Adulto , Anciano , Anciano de 80 o más Años , Secuencia de Aminoácidos , Animales , Anticuerpos Monoclonales/metabolismo , Especificidad de Anticuerpos/inmunología , Antígenos de Carbohidratos Asociados a Tumores/química , Antígenos de Carbohidratos Asociados a Tumores/metabolismo , Biomarcadores de Tumor , Neoplasias de la Mama/inmunología , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Neoplasias del Colon/inmunología , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Femenino , Glicopéptidos/química , Glicopéptidos/metabolismo , Humanos , Masculino , Ratones , Persona de Mediana Edad , Estadificación de Neoplasias , Neoplasias/metabolismo , Neoplasias/patología , Unión Proteica/inmunología
5.
JCO Glob Oncol ; 8: e2100251, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35245084

RESUMEN

PURPOSE: The HOLA COVID-19 study sought to evaluate the impact of COVID-19 on oncology practices across Latin America (LATAM), challenges faced by physicians, and how practices and physicians adapted while delivering care to patients with cancer. METHODS: This international cross-sectional study of oncology physicians in LATAM included a 43-item anonymous online survey to evaluate changes and adaptations to clinical practice. Multivariable logistic regression analyses were used to evaluate the association of caring for patients with COVID-19 and changes to clinical practice. RESULTS: A total of 704 oncology physicians from 19 countries completed the survey. Among respondents, the most common specialty was general oncology (34%) and 56% of physicians had cared for patients with COVID-19. The majority of physicians (70%) noted a decrease in the number of new patients evaluated during the COVID-19 pandemic when compared with prepandemic, and 73% reported adopting the use of telemedicine in their practice. More than half (58%) of physicians reported making changes to the treatments that they offered to patients with cancer. In adjusted models, physicians who had cared for patients with COVID-19 had higher odds of changing the type of chemotherapy or treatments that they offered (adjusted odds ratio 1.81; 95% CI, 1.30 to 2.53) and of delaying chemotherapy start (adjusted odds ratio 2.05; 95% CI, 1.49 to 2.81). Physicians identified significant delays in access to radiation and surgical services, diagnostic tests, and supportive care. CONCLUSION: The COVID-19 pandemic has significantly disrupted global cancer care. Although changes to health care delivery are a necessary response to this global crisis, our study highlights the significant disruption and changes to the treatment plans of patients with cancer in LATAM resulting from the COVID-19 health care crisis.


Asunto(s)
COVID-19 , Neoplasias , Estudios Transversales , Atención a la Salud , Humanos , América Latina/epidemiología , Neoplasias/terapia , Pandemias , Atención al Paciente , SARS-CoV-2
6.
JCO Glob Oncol ; 8: e2200123, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35994695

RESUMEN

On February 24, 2022, a war began within the Ukrainian borders. At least 3.0 million Ukrainian inhabitants have already fled the country. Critical infrastructure, including hospitals, has been damaged. Children with cancer were urgently transported to foreign countries, in an effort to minimize interruption of their life-saving treatments. Most adults did not have that option. War breeds cancer-delaying diagnosis, preventing treatment, and increasing risk. We project that a modest delay in care of only 4 months for five prevalent types of cancer will lead to an excess of over 3,600 cancer deaths in the subsequent years. It is critical that we establish plans to mitigate that risk as soon as possible.


Asunto(s)
Neoplasias , Investigación , Adulto , Conflictos Armados , Niño , Humanos , Neoplasias/diagnóstico , Neoplasias/epidemiología , Neoplasias/terapia , Ucrania/epidemiología
8.
Cancers (Basel) ; 13(22)2021 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-34830771

RESUMEN

Breast cancer is a public health concern and is currently the fifth cause of mortality worldwide. Identification of different biological subtypes is essential for clinical management; therefore, the role of pathologists is essential and useful tools for immunohistochemistry diagnosis are needed. Polypeptide-GalNAc-transferases are emerging novel biomarkers related to cancer behavior and GalNAc-T13, correlated with aggressiveness in some tumors, is an interesting candidate. Few monoclonal antibodies reacting with native proteins, and not affected by fixation and paraffin embedding, have been reported. The aim of this work was to develop a useful monoclonal antibody anti-GalNAc-T13 and to assess its potential significance in breast cancer diagnosis. We evaluated 6 human breast cancer cell lines, 338 primary breast tumors and 48 metastatic lymph nodes and looked for clinical significance correlating GalNAc-T13 expression with patients' clinical features and survival. We found high GalNAc-T13 expression in 43.8% of the cases and observed a significant higher expression in metastatic lymph nodes, correlating with worse overall survival. We hypothesized several possible molecular mechanisms and their implications. We conclude that GalNAc-T13 may be a novel biomarker in breast cancer, useful for routine pathological diagnosis. Elucidation of molecular mechanisms related to aggressiveness should contribute to understand the role of GalNAc-T13 in breast cancer biology.

9.
Int J Parasitol ; 38(3-4): 265-76, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17892882

RESUMEN

Protein glycosylation is an important post-translational modification underlying host-parasite interactions, which may determine the outcome of infection. Although Mesocestoides vogae represents an important model for investigating the various aspects of cestode biology, virtually no information is available about the structure and synthesis of glycans in this parasite. In this work, focused on the initiation pathway of mucin-type O-glycosylation in M. vogae, we characterized O-glycoproteins bearing the simple mucin-type cancer-associated Tn and sialyl-Tn antigens, and the expression and activity of ppGalNAc-T, the key enzyme responsible for the first step of mucin-type O-glycosylation. Using immunohistochemistry, Tn and sialyl-Tn antigens were detected mainly in the tegument (microtriches) and in parenchymal cells. Tn expression was also observed in lateral nerve cords. Both Tn and sialyl-Tn antigens were detected in in vitro cultured parasites. Based on their electrophoretic mobility, Tn- and sialyl-Tn-bearing glycoproteins from M. vogae were separated into several components of 22 to 60 kDa. The observation that Tn and sialyl-Tn glycoproteins remained in the 0.6N perchloric acid-soluble fraction suggested that they could be good candidates for characterizing mucin-type glycosylation in this parasite. O-glycoproteins were purified and initially characterized using a proteomic approach. Immunohistochemical analysis of the tissue distribution of ppGalNAc-T revealed that this enzyme is expressed in the sub-tegumental region and in the parenchyma of the parasite. In M. vogae cultured in vitro, ppGalNAc-T was mainly detected in the suckers. Using a panel of 8 acceptor substrate synthetic peptides, we found that M. vogae ppGalNAc-T preferentially glycosylate threonine residues, the best substrates being peptides derived from human mucin MUC1 and from Trypanosoma cruzi mucin. These results suggest that M. vogae might represent a useful model to study O-glycosylation, and provide new research avenues for future studies on the glycopathobiology of helminth parasites.


Asunto(s)
Antígenos Helmínticos/metabolismo , Mesocestoides/metabolismo , Animales , Antígenos Helmínticos/análisis , Antígenos de Carbohidratos Asociados a Tumores/metabolismo , Western Blotting , Secuencia de Carbohidratos , Infecciones por Cestodos/metabolismo , Electroforesis en Gel de Poliacrilamida , Glicosilación , Interacciones Huésped-Parásitos , Inmunohistoquímica , Mesocestoides/química , Ratones , Ratones Endogámicos , Mucinas/metabolismo , N-Acetilgalactosaminiltransferasas/análisis , Parasitología/métodos , Polipéptido N-Acetilgalactosaminiltransferasa
10.
Oncol Lett ; 16(1): 225-234, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29928405

RESUMEN

Colorectal carcinoma (CRC) is the second leading cause of cancer mortality worldwide. O-glycosylated mucins at the cell surface of colonic mucosa exhibit alterations in cancer and are involved in fundamental biological processes, including invasion and metastasis. Certain members of the GalNAc-transferase family may be responsible for these changes and are being investigated as novel biomarkers of cancer. In the present study the prognostic significance of GalNAc-T6 was investigated in patients with CRC patients. GalNAc-T6 expression was observed in all three colon cancer cell lines analyzed by reverse transcription-polymerase chain reaction, immunofluorescence and flow cytometry. A cohort of 81 colon cancer specimens was analyzed by immunohistochemical staining using MAb T6.3. It was demonstrated that GalNAc-T6 was expressed in 35/81 (43%) cases of colon cancer but not in the normal colonic mucosa. No association was observed with the clinical-pathologic parameters. However, patients expressing GalNAc-T6 had a significantly increased overall survival (median, 58 months; P<0.001) compared with GalNAc-T6 negative patients, especially those with advanced disease. These results suggest that GalNAc-T6 expression predicts an improved outcome in patients with CRC. The molecular mechanism underlying the less aggressive behavior of colon cancer cells expressing GalNAc-T6 remains to be elucidated.

11.
J Cancer Epidemiol ; 2017: 6170290, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28744312

RESUMEN

BACKGROUND: Incorporation of molecular analysis of the epidermal growth factor receptor (EGFR) gene into routine clinical practice represents a milestone for personalized therapy of the non-small-cell lung cancer (NSCLC). However, the genetic testing of EGFR mutations has not yet become a routine clinical practice in developing countries. In view of different prevalence of such mutations among different ethnicities and geographic regions, as well as the limited existing data from Latin America, our aim was to study the frequency of major types of activating mutations of the EGFR gene in NSCLC patients from Uruguay. METHODS: We examined EGFR mutations in exons 18 through 21 in 289 NSCLC Uruguayan patients by PCR-direct sequencing. RESULTS: EGFR mutations were detected in 53 of the 289 (18.3%) patients, more frequently in women (23.4%) than in men (14.5%). The distribution by exon was similar to that generally reported in the literature. CONCLUSIONS: This first epidemiological study of EGFR mutations in Uruguay reveals a wide spectrum of mutations and an overall prevalence of 18.3%. The background ethnic structure of the Uruguayan population could play an important role in explaining our findings.

12.
J Histochem Cytochem ; 54(3): 317-28, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16260590

RESUMEN

Mucin O-glycosylation is characterized in cancer by aberrant expression of immature carbohydrate structures (Tn, T, and sialyl-Tn antigens). The UDP-N-acetyl-D-galactosamine: polypeptide N-acetylgalactosaminyltransferases (ppGalNAc-T) family enzymes regulate the initial steps of mucin O-glycosylation and could be responsible for the altered glycosylation observed in cancer. Considering that we recently found the ppGalNAc-T6 mRNA expressed in breast carcinomas, we produced a highly specific monoclonal antibody (MAb T6.3) to assess the expression profile of ppGalNAc-T6 protein product in breast tissues. The expression of ppGalNAc-T6 by breast carcinoma cells was confirmed on MCF-7 and T47D cell lines. In formalin-fixed tissues, ppGalNAc-T6 expression was observed in 60/74 (81%) breast cancers, 21/23 (91.3%) adjacent ductal carcinoma in situ (DCIS), 4/20 benign breast lesions (2/2 sclerosing adenosis and 2/13 fibroadenoma), and in 0/5 normal breast samples. We observed a statistically significant association of ppGalNAc-T6 expression with T1 tumor stage. This fact, as well as the observation that ppGalNAc-T6 was strongly expressed in sclerosing adenosis and in most DCIS, suggests that ppGalNAc-T6 expression could be an early event during human breast carcinogenesis. Considering that an abnormal O-glycosylation greatly contributes to the phenotype and biology of breast cancer cells, ppGalNAc-T6 expression could provide new insights about breast cancer glycobiology.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/enzimología , N-Acetilgalactosaminiltransferasas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Animales , Anticuerpos Monoclonales , Enfermedades de la Mama/enzimología , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/enzimología , Carcinoma Lobular/enzimología , Carcinoma Papilar/enzimología , Femenino , Humanos , Inmunohistoquímica , Glándulas Mamarias Humanas/enzimología , Metaplasia , Ratones , Persona de Mediana Edad , N-Acetilgalactosaminiltransferasas/inmunología
13.
J Histochem Cytochem ; 54(3): 289-99, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16148312

RESUMEN

A deregulation of several MUC genes (MUC1, MUC2, MUC3, MUC5AC, and MUC6) was previously demonstrated in breast carcinomas. Considering that recently we found the "non-mammary" MUC5B mRNA in primary breast tumors (Berois et al. 2003), we undertook the present study to evaluate the expression profile of MUC5B protein product in breast tissues, using LUM5B-2 antisera raised against sequences within the non-glycosylated regions of this apomucin. Expression of MUC5B by breast cancer cells was confirmed by immunocytochemistry, in situ hybridization, and Western blot on MCF-7 cancer cells. Using an immunohistochemical procedure, MUC5B apomucin was detected in 34/42 (81%) primary breast tumors, in 13/14 (92.8%) samples of non-malignant breast diseases, in 8/19 (42.1%) samples of normal-appearing breast epithelia adjacent to cancer, and in 0/5 normal control breast samples. The staining pattern of MUC5B was very different when comparing breast cancer cells (cytoplasmic) and non-malignant breast cells (predominantly apical and in the secretory material). We analyzed MUC5B mRNA expression using RT-PCR in bone marrow aspirates from 22/42 patients with breast cancer to compare with MUC5B protein expression in the primary tumors. Good correlation was observed because the six MUC5B-positive bone marrow samples also displayed MUC5B expression in the tumor. Our results show, for the first time at the protein level, that MUC5B apomucin is upregulated in breast cancer. Its characterization could provide new insights about the glycobiology of breast cancer cells.


Asunto(s)
Neoplasias de la Mama/metabolismo , Mama/metabolismo , Mucinas/biosíntesis , Adenocarcinoma Mucinoso/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Apoproteínas/biosíntesis , Western Blotting , Médula Ósea/metabolismo , Enfermedades de la Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Carcinoma Lobular/metabolismo , Carcinoma Papilar/metabolismo , Línea Celular Tumoral , Femenino , Humanos , Inmunohistoquímica , Hibridación in Situ , Glándulas Mamarias Humanas/metabolismo , Persona de Mediana Edad , Mucina 5B , Mucinas/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Regulación hacia Arriba
14.
FASEB J ; 19(14): 1957-68, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16319139

RESUMEN

Heme oxygenase-1 (HO-1) is the rate limiting enzyme of heme catabolism whereas indoleamine 2,3 dioxygenase (IDO) catabolizes tryptophan through the kynurenine pathway. We analyzed the expression and biological effects of these enzymes in rat and human breast cancer cell lines. We show that rat (NMU and 13762) but not human cells (MCF-7 and T47D) express HO-1. When overexpressed, we found this enzyme to have anti-proliferative and proapoptotic effects by antioxidant mechanisms in these four cell lines. We show that IDO is expressed by rat and human breast cancer cells. IDO inhibition with 1-MT and siRNA leads to diminished proliferation in rat cells. In contrast, HO-1 negative human cell lines increase proliferation upon IDO inhibition. Since we also demonstrate that IDO inhibits the anti-proliferative HO-1, we propose that IDO has opposite effects on proliferation depending on the coexpression or not of HO-1. We also describe that HO-1 inhibits IDO at the post-translational level through heme starvation. In vivo, we show that rat normal breast expresses HO-1 and IDO. In contrast, N-nitrosomethylurea-induced breast adenocarcinomas only express IDO. In conclusion, we show that HO-1/IDO cross-regulation modulates apoptosis and proliferation in rat and human breast cancer cells.


Asunto(s)
Neoplasias de la Mama/patología , Hemo-Oxigenasa 1/fisiología , Indolamina-Pirrol 2,3,-Dioxigenasa/farmacología , Neoplasias Mamarias Animales/patología , Animales , Antineoplásicos/farmacología , Antioxidantes/metabolismo , Apoptosis , Western Blotting , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Hemo/química , Hemo-Oxigenasa 1/metabolismo , Humanos , Inmunohistoquímica , Lentivirus/genética , Neoplasias Mamarias Animales/metabolismo , Metilnitrosourea/farmacología , Oxígeno/metabolismo , Procesamiento Proteico-Postraduccional , ARN Interferente Pequeño/metabolismo , Ratas , Transducción de Señal
15.
Oncol Rep ; 14(1): 219-27, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15944793

RESUMEN

The simple mucin-type truncated O-glycans Tn (GalNAc-O-Ser/Thr) and sialyl-Tn (STn) antigens are useful diagnostic markers for human colon cancer. We herein report the characterization of 1,2-dimethylhidrazine (DMH)-induced colon cancer in rats as a new model for the study of aberrant O-glycosylation products during carcinogenesis. Evaluated by immunohistochemistry, both anti-Tn and anti-STn MAbs revealed no staining of normal colonic mucosa. On the contrary, Tn and STn were expressed by the first lesions detected following carcinogen administration (aberrant crypt foci), observing the most intense and uniform pattern in crypts with severe dysplasia. Adenocarcinomas with non-secreting components showed moderately and strong stain, but mucin-secreting carcinomas were mildly stained. The biochemical characterization of soluble Tn glycoproteins from ascitic fluids of rats with colon cancer revealed that Tn is bearing high molecular weight glycoproteins (containing sialic acid and/or GlcNAc and GalNAc), which migrated as two major components (one of approximately 220 kDa and other>500 kDa). Evaluated by CsCl gradient ultracentrifugation and perchloric acid precipitation, it was shown that Tn is carried for mucins. These results indicate that Tn and STn are pre-cancerous biomarkers in colon of rats treated with DMH. This model of rat colon cancer could be useful to study in vivo the temporal sequence of molecular events responsible for the deregulation of O-glycosylation pathways during colon carcinogenesis, and could contribute to improve the evaluation of diagnostic and therapeutic strategies based on the utilization of Tn and STn antigens.


Asunto(s)
Antígenos de Carbohidratos Asociados a Tumores/análisis , Biomarcadores de Tumor/análisis , Neoplasias del Colon/patología , Mucinas/análisis , Lesiones Precancerosas/patología , Animales , Colon/química , Colon/efectos de los fármacos , Colon/patología , Neoplasias del Colon/inducido químicamente , Neoplasias del Colon/metabolismo , Diagnóstico Diferencial , Dimetilhidrazinas , Femenino , Glicoproteínas/metabolismo , Inmunohistoquímica , Lesiones Precancerosas/metabolismo , Ratas , Ratas Wistar
16.
Rev. méd. Chile ; 144(10): 1305-1318, oct. 2016.
Artículo en Español | LILACS | ID: biblio-845445

RESUMEN

Pancreatic cancer is a malignancy of great impact in developed countries and is having an increasing impact in Latin America. Incidence and mortality rates are similar for this cancer. This is an important reason to offer to the patients the best treatments available. During the Latin American Symposium of Gastroenterology Oncology (SLAGO) held in Viña del Mar, Chile, in April 2015, a multidisciplinary group of specialists in the field met to discuss about this disease. The main conclusions of this meeting, where practitioners from most of Latin American countries participated, are listed in this consensus that seek to serve as a guide for better decision making for patients with pancreatic cancer in Latin America.


Asunto(s)
Humanos , Neoplasias Pancreáticas/terapia , Adenocarcinoma/terapia , Guías de Práctica Clínica como Asunto , Manejo de la Enfermedad , Conferencias de Consenso como Asunto , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapéutico , Quimioradioterapia , América Latina , Antimetabolitos Antineoplásicos/uso terapéutico
17.
J Histochem Cytochem ; 58(6): 553-65, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20197492

RESUMEN

Galectin-3 (Gal-3) is a multifunctional protein that plays different roles in cancer biology. To better understand the role of Gal-3 and its ligands during colon carcinogenesis, we studied its expression in tumors induced in rats treated with 1,2-dimethylhydrazine (DMH) and in human tissues. Normal colon from untreated rats showed no staining using two specific monoclonal antibodies. In contrast, morphologically normal colon from DMH-treated rats and dysplastic aberrant crypt foci were strongly stained, indicating that increased Gal-3 expression is an early event during the neoplastic transformation in colon cells. Gal-3 was weakly expressed in adenocarcinomas. Overall, the Gal-3 expression pattern observed in the DMH rat model closely resembles that displayed by human colon stained with the same antibodies. We also found that Gal-3 phosphorylation diminishes in serines while increasing in tyrosines during rat colon carcinogenesis. Finally, we showed that Gal-3-ligands expression is strikingly similar in rat and human malignant colon and in non-malignant tissues. In conclusion, the DMH-induced rat colon cancer model displays expression patterns of Gal-3 and its ligands very similar to those observed in human samples. This animal model should contribute to clarifying the role of Gal-3 in colon carcinogenesis and also to finding effective preventive cancer agents based on Gal-3 targeting.


Asunto(s)
Adenocarcinoma/metabolismo , Neoplasias del Colon/metabolismo , Galectina 3/metabolismo , Adenocarcinoma/patología , Adenocarcinoma/fisiopatología , Animales , Colon/metabolismo , Neoplasias del Colon/patología , Neoplasias del Colon/fisiopatología , Femenino , Galectina 3/genética , Humanos , Inmunohistoquímica , Ligandos , Modelos Animales , Fosforilación , Reacción en Cadena de la Polimerasa , Empalme del ARN , ARN Mensajero/genética , Ratas , Ratas Wistar
18.
Exp Parasitol ; 116(2): 129-36, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17300782

RESUMEN

Expression of Tk antigen, a truncated carbohydrate antigen, was examined in helmith parasites. Using the monoclonal antibody LM389, this antigen was detected in extracts from Taenia hydatigena, Mesocestoides vogae (syn corti), and Taenia crassiceps. No reactivity was observed in Thysanosoma spp., Dipylidium caninum, Fasciola hepatica, and Nyppostrongylus brasiliensis. On the basis of their electrophoretic mobility, different patterns of Tk-bearing glycoproteins were observed among T. hydatigena, M. corti and T. crassiceps by immunoblotting, with certain components resolved as broad bands typical of mucin-like glycoproteins. Most Tk-reactive material remained in the 0.6 N perchloric acid-soluble fraction, confirming that Tk epitopes are carried by mucin-type glycoproteins. Immunohistochemical analysis revealed that in T. hydatigena, Tk antigen is mainly expressed in the tegument, whereas in M. corti the reactivity was principally observed in the subtegumental parenchyma. The presence of a novel tumor-associated carbohydrate antigen in invertebrates, contributes to strengthen the notion that truncated mucin-type O-glycosylation is a normal phenomenon in parasitic worms and may help identify new biological characteristics of helminth parasites.


Asunto(s)
Antígenos Helmínticos/análisis , Antígenos de Carbohidratos Asociados a Tumores/análisis , Helmintos/inmunología , Animales , Antígenos Helmínticos/química , Antígenos de Carbohidratos Asociados a Tumores/química , Western Blotting , Electroforesis en Gel de Poliacrilamida , Ensayo de Inmunoadsorción Enzimática , Epítopos/análisis , Epítopos/química , Técnica del Anticuerpo Fluorescente , Inmunohistoquímica , Percloratos/química , Solubilidad
19.
Rev. méd. Urug ; 28(4): 241-9, dic. 2012. tab, graf
Artículo en Español | LILACS | ID: lil-667772

RESUMEN

Introducción: el cáncer de mama (CM) constituye una enfermedad heterogénea reconociéndose subtipos con diferentes características mediante, entre otras técnicas, el estudio del nivel de expresión tumoral de los receptores hormonales (RRHH) y del HER2. Previamente reportamos la relación entre estos subtipos y características clínico-patológicas en pacientes uruguayas. Objetivo:analizar la sobrevida libre de enfermedad (SVLE) de pacientes uruguayas con cáncer de mama de acuerdo a su subtipo biológico, definido en base a la expresión tumoral de HER2 y RRHH evaluada mediante inmunohistoquímica. Material y método:se revisaron historias clínicas de pacientes intervenidas quirúrgicamente por CM estadios I-III en un período de dos años, realizándose el cálculo de SVLE para todas las pacientes y según subtipo biológico. Resultados:con seguimiento mediano de 40 meses, la SVLE a dos años para el total de las pacientes fue de 92,3%; 94% para las pacientes RRHH+/HER2-, 91% para las triple negativas (TN) y 71,4% para las HER2+. La comparación de las curvas de SVLE, según los diferentes subtipos, mostró menor SVLE para las pacientes HER2+ (p = 0,03) y similar SVLE de las pacientes RRHH+/HER2- y TN (p = 0,86). Conclusiones: las pacientes uruguayas con CM presentan una SVLE a dos años acorde a los reportes internacionales. Las pacientes HER2+ presentan una mayor tasa de recidivas,lo cual también es coincidente a lo reportado. La similar SVLE a dos años de las pacientes RRHH+/HER 2- y de las TN no se explicaría por diferencias en características clínico-patológicas, planteándose como hipótesis una mayor proporción de pacientes del subtipo luminal B entre las pacientes RRHH+/ HER 2-.


Introduction: breast cancer constitutes an heterogeneous disease. Two sub-types have been distinguished through the study of the tumor expression level of hormone receptors tumors, and level of HER2 expression, among other techniques. We previously reported therelation between these sub-types and the clinical and pathological characteristics of Uruguayan women.Objective: to analyse the disease-free survival (DFS) of Uruguayan patients with breast cancer, according to their biological sub-type, defined based on the tumor expression of hormone receptors and HER2 expression which were assessed by immune-histologicalchemistry staining. Method: all clinical records of patients who had undergone breast cancer surgery (Stages I-III) during a two year period were reviewed. The disease-free survival rate was calculated for all patients and according to their biological profile.Results: forty months follow up revealed disease-free survival upon two years of 92.3% for all patients;94% for hormone receptor positive /HER2 negative patients, 91% for triple negative patients, and 71.4% for hormone receptor positive patients.Comparing the DFS curves, for the different sub-types, evidenced a lower DFS for HER2+ patients (p = 0.03), and similar DFS for hormone receptor positive/HER2 negative and triple negative (p = 0.86). Conclusions:uruguayan patients with breast cancershow a two-year-DFS that matches international reports. HER2+ patients evidence a higher relapse rate, also consistent with international reports. Similar DFS upon two years, between hormone receptor positive/HER2 negative patients and triple negative patients cannot be due to differences in the clinical-pathologicalcharacteristics, thus a hypothesis is considered: there is a larger proportion of patients of the luminal B breast cancer sub-type among hormone receptor positive/HER2 negative patients.


Introdução: o câncer de mama (CM) é uma patologia heterogênea, apresentando subtipos com diferentes características determinadas, entre outras técnicas, pelo estudo do nível de expressão tumoral dos receptoreshormonais (RRHH) e do HER2. Em um artigo anterior descrevemos a relação entre esses subtipos e as características clínico-patológicas em pacientes uruguaias. Objetivo: analisar a sobrevida livre de enfermidade(SVLE) de pacientes uruguaias com CM de acordo a seu subtipo biológico, definido pela expressão tumoral deHER2 e RRHH avaliada por imunohistoquímica. Material e método:foram revisados os prontuários de pacientes operadas por cirurgia por CM estadios I-III em um período de dois anos; realizou-se o cálculo de SVLE de todas as pacientes e de acordo com o subtipo biológico. Resultados: o seguimento com uma mediana de 40meses mostrou uma SVLE aos dois anos para todas as pacientes de 92,3%; 94% para as pacientesRRHH+/HER2-, 91% para a triple negativa (TN) e 71,4% para as HER2+.A comparação das curvas de SVLE, segundo os diferentes subtipos, mostrou uma menor SVLE para as pacientes HER2+ (p = 0,03) e similar SVLE para as pacientes RRHH+/HER2- y TN (p = 0,86). Conclusões: as pacientes uruguaias com CM apresentam uma SVLE a dois anos compatível com resultados internacionais. As pacientes HER2+ apresentaram uma taxa maior de recidivas, resultados que coincidemcom resultados internacionais. A SVLE aos dois anos similar para pacientes RRHH+/HER2- e TN não pode serexplicada pelas diferenças nas características clínico-patológicas, considerando-se como hipótese umaproporção maior de pacientes do subtipo luminal B entre as pacientes RRHH+/HER2-.


Asunto(s)
Análisis de Supervivencia , Neoplasias de la Mama , Pronóstico , Receptores de Estrógenos , Receptores de Progesterona
20.
Rev. méd. Urug ; 26(3): 145-153, set. 2010. tab
Artículo en Español | LILACS | ID: biblio-961486

RESUMEN

Introducción: el cáncer de mama (CM), principal causa de muerte por cáncer en la mujer uruguaya, constituye una enfermedad heterogénea. El estudio de la expresión tumoral del receptor del factor de crecimiento epidérmico-2 (HER2), el receptor de estrógenos (RE) y el receptor de progesterona (RP) permite reconocer subtipos con diferentes características clínico-patológicas y evolutivas. Objetivos: conocer el perfil de expresión tumoral de HER2, RE y RP y su relación con características clínico-patológicas en pacientes uruguayas con CM. Material y método: se revisaron las historias clínicas de pacientes intervenidas quirúrgicamente por CM invasivo en un período de dos años, seleccionándose las que contaban con la determinación de RE, RP y HER2 mediante inmunohistoquímica. Se comparó el perfil de expresión de estos marcadores con la edad al diagnóstico, tipo y grado histológico (GH) y estadio patológico (TNM). Resultados: se seleccionaron 197 pacientes cuyas características fueron edad media: 55 años, carcinoma ductal: 85%, GH 1-2: 59%, estadio: I-II: 75%, metástasis axilares: 51%, RE/RP+: 78%, HER2+: 10%. Se definieron tres subtipos: HER2- RE/RP+ (73%), HER2+ (10%) y triple negativo (TN) (17%). Los subtipos TN y HER2+ se asociaron con mayor grado histológico (p<0,05) y el TN con menor edad al diagnóstico (p<0,05) que el subtipo HER2-, RE/RP+. Conclusiones: el porcentaje de pacientes con CM invasivo subtipo HER2+ (10%) es menor que el reportado por otros estudios (17%-28%). En concordancia con estudios previos, los subtipos TN y HER2+ se correlacionaron con tumores más indiferenciados y el TN se presentó en pacientes más jóvenes


Summary Introduction: breast cancer, the main cause of death of Uruguayan women, is an heterogeneous disease. Study of the tumoral expression of the Human Epidermal growth factor Receptor-2 (HER2), the estrogen receptor and the progesterone receptor enables the recognition of sub-types with different clinical, and pathological characteristics and evolution. Objectives: to learn about the HER2, estrogen receptor and progesterone receptor tumoral expression profile and their relationship with clinical-pathological characteristics in Uruguayan patients with breast cancer. Method: we reviewed the medical record of patients who underwent surgery for invasive breast cancer within a two year period, and we selected those who had determination of estrogen receptor, progesterone receptor and HER2 through immune-histochemestry. We compared the expression profile of these markers with the age at the time of diagnosis, the histological type and degree and the pathological status. Results: we selected 197 patients with the following characteristics: average age: 55 years old, ductal carcinoma: 85%, histological degree 1-2: 59%; stage I-II: 75%, axillary metastasis: 51%, progesterone receptor/estrogen receptors+ (RE/RP+): 78%, HER2+: 10%. Three subtypes were defined: HER2- RE/RP+ (73%), HER2+ (10%) and triple negative (TN) (17%). Subtypes TN and HER2+ were associated with a greater histological degree (GH) (p<0,05) and the TN with lower age at the time of diagnosis than the HER2-, RE/RP+ subtype. Conclusions: the percentage of patients with HER2+ subtype invasive breast cancer (10%) is lower than the one reported in others studies. In accordance with previous studies, TN and HER2+ subtypes correlated with less differentiated tumors and TN subtype occurred in younger patients


Résumé Introduction: le cancer de sein (CS), principal responsable de mort par cancer des uruguayennes, est une maladie hétérogène. L’étude de l’expression tumorale du récepteur du facteur de croissance épidermique 2 (HER-2), le récepteur d’oestrogène (RE) et le récepteur de progestérone (RP) permet de reconnaître des sous-types à caractéristiques cliniques pathologiques et évolutives variées. Objectif: connaître le profil de expression tumorale de HER-2, RE et RP et leur lien avec des données cliniques pathologiques chez des patientes uruguayennes atteintes de cancer de sein. Matériel et méthode: on fait la révision clinique des patientes atteintes de CS ayant subi une intervention chirurgicale pour une période de deux ans, choisissant celles portant la détermination de HER-2, RP et RE par immunohistochimie. On compare le profil de manifestation de ces marqueurs à l’âge au diagnostic, type et degré histologique (GH) et stade pathologique (TNM). Résultats: 197 patientes furent sélectionnées dont voici les caractéristiques: 55 ans (moyenne), 85% carcinome ductal, 59% GH 1-2; 75% stade I- II; 51% métastase axillaire; 78% RE-RP +; 10% HER2+; trois sous-types furent définis: HER2- RE/RP+ (73%), HER2+ (10%) et triple négatif (TN) (17%). Les sous-types TN et HER2+ furent associés à un degré histologique plus grand (p<0,05) et le TN à un âge plus bas au diagnostic (p<0,05) que le sous-type HER2-, RE/RP+. Conclusions: le pourcentage de patientes avec CM invasif sous-type HER2+ (10%) est inférieur à celui reporté par d’autres études (17%-28%). En concordance avec des études préalables, les sous-types TN y HER2+ ont été mis en relation avec des tumeurs plus indifférenciées et le TN a été présent chez des patientes plus jeunes.


Resumo Introdução: o câncer de mama (CM), principal causa de morte por câncer em mulheres uruguaias, é uma doença heterogênea. O estudo da expressão tumoral do receptor do fator de crescimento epidérmico-2 (HER2), do receptor de estrógeno (RE) e do receptor de progesterona (RP) permite reconhecer subtipos com diferentes características clínico-patológicas e de evolução. Objetivos: conhecer o perfil de expressão tumoral de HER2, RE e RP e sua relação com as características clínico-patológicas em pacientes uruguaias com CM. Material e método: os prontuários de pacientes submetidas a cirurgia por CM invasivo em um período de dois anos foram revisados. Foram selecionadas as que incluíam a determinação de RE, RP e HER2 por imuno-histoquímica. O perfil de expressão destes marcadores foi comparado com a idade no momento do diagnóstico, tipo e grau histológico (GH) e estádio patológico (TNM). Resultados: foram selecionadas 197 pacientes cujas características eram idade media: 55 anos, carcinoma ductal: 85%, GH 1-2: 59%, estádio: I-II: 75%, metástases axilares: 51%, RE/RP+: 78%, HER2+: 10%. Foram definidos três subtipos: HER2- RE/RP+ (73%), HER2+ (10%) e triplo negativo (TN) (17%). Os subtipos TN e HER2+ estavam associados a um maior grau histológico (p<0,05) e o TN com menor idade no momento do diagnóstico (p<0,05) que o subtipo HER2-, RE/RP+. Conclusões: a porcentagem de pacientes com CM invasivo subtipo HER2+ (10%) é menor que o informado por outros estudos (17%-28%). No entanto houve concordância com estudos anteriores nos quais os subtipos TN e HER2+ estavam correlacionados com tumores mais indiferenciados e o TN em pacientes más jovens.


Asunto(s)
Neoplasias de la Mama/patología , Receptor ErbB-2/análisis , Receptores de Progesterona , Receptores de Estrógenos
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