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1.
Front Oncol ; 13: 1304457, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38322288

RESUMEN

NUT carcinoma is a rare subcategory of squamous cell carcinoma. The latter is primarily characterized by the fusion of the coding sequence NUTM1 on chromosome 15q14 with BRD4 or BRD3, both of which are acetyl-histone binding bromodomains. This tumor is often misdiagnosed due to its rarity and its histological similarity with other squamous cell carcinomas. It typically presents as a poorly differentiated squamous cell carcinoma in the head, neck, and mediastinal region, and has no distinct clinical characteristics that set it apart from other malignancies. Although uncommon, other NUT carcinomas have been reported in the literature outside of the midline region. Through next-generation sequencing, we were able to correctly diagnose our patient with the first-documented case of NUT carcinoma of hepatic-only origin.

2.
Int J Surg Case Rep ; 90: 106654, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34915443

RESUMEN

INTRODUCTION AND IMPORTANCE: Pancreatic adenocarcinoma is one of the leading causes of death. Presentation with colonic metastases is far less frequently reported in the literature and may be misdiagnosed as colonic adenocarcinoma. We report the case of a female patient with metastatic pancreatic adenocarcinoma that presented with a sigmoid obstruction. CASE PRESENTATION: A 66-year-old female presented with constipation and abdominal pain. She was found to have an obstructing sigmoid colon lesion, multiple metastatic lesions in the liver, and a pancreatic tail lesion. She underwent left hemicolectomy and ostomy placement. The gross pathology of the colon and needle biopsy of the liver was consistent of pancreatobiliary origin. Genomic screening performed, patient found to be KRAS G12R mutated. She was given one cycle of chemotherapy, thereafter was referred to hospice care. CLINICAL DISCUSSION: Primary metastatic pancreatic cancer is now the 2nd most diagnosed cancer in the United States after lung cancer. The prognosis for the malignancy is poor, patients are usually diagnosed late at the time that the tumor has metastasized to other organs. Colonic metastasis is a rarely seen and far less frequently reported in the literature. Next-generation-sequencing was performed at baseline to further characterize her tumor for any actionable mutations. CONCLUSION: Pancreatic adenocarcinoma is an aggressive malignancy with a poor prognosis. Next-generation-sequencing may offer targeted therapy if an actionable mutation is present such as our patient's, however due to late diagnosis, rapid clinical deterioration, and next-generation sequencing delay we were unable to alter the patient's outcome.

3.
J Pancreat Cancer ; 7(1): 65-70, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34901697

RESUMEN

Purpose: The KRAS proto-oncogene is involved in the RAS/MAPK pathway. KRAS is present in the wild type or mutated forms. The oncogene KRAS is frequently mutated in various cancers. At the time that amino acid glycine is mutated, KRAS protein acquires oncogenic properties that result in the tumor cell growth, proliferation, and cancer progression. There has been limited understanding of the different mutations at codon 12. The consequences of such mutations is not fully understood. Various G12X mutations in pancreatic cancer patients have been examined, with the most common mutations being G12D (40%), G12V (30%), and G12R (15-20%). Now we are understanding that G12X mutations in the KRAS are not all equal. Methods: In a single-arm exploratory study, we accrued 13 KRAS-G12X-mutated pancreatic patients (KRAS G12D, G12V, and G12R). They were divided into two groups: group 1 consisted of seven patients with G12D and G12V and group 2 included six patients with the KRAS G12R mutation. All patients were treated with the combination of gemcitabine at 1250 mg/m2 intravenous weekly for 3 weeks and oral cobimetinib 20 mg b.i.d. for 3 weeks. This was followed by a week of rest before the initiation of the next cycle. Results: In the first cohort, seven patients were on treatment, all of whom progressed and died within the 2 months of the study. In the second cohort, one of six patients achieved partial response, and five achieved stable disease. Median progression-free survival was 6 months (9% confidence interval 3.0-9.3 months) and overall survival has been reached at 8 months. Common adverse reactions included rash, fatigue, nausea, and vomiting (grades 2 and 3). Cancer antigen CA19-9 decreased by >50% in all group 2 patients. Conclusion: Our pancreatic cancer patients were heavily pretreated (all had received FOLFIRINOX and gemcitabine/nab-paclitaxel) before the entry into our trial. Upon entry into our trial, all patients were treated with the combination of gemcitabine and oral cobimetinib. Therefore, this constituted the second exposure of the patients to gemcitabine. This study illustrates a new discovery, which can potentially target 15-20% of pancreatic cancer patients and allow for a significant improvement in their prognosis. We will be conducting randomized phase II trials to substantiate our findings.

4.
Artículo en Inglés | MEDLINE | ID: mdl-34667063

RESUMEN

This is the first case report of a 60-yr-old female who underwent therapy for metastatic pancreatic cancer with fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX). Upon the progression of her disease, she was switched to gemcitabine and nab-paclitaxel. Per genomic sequencing, her tumor was found to be a KRAS wild-type and BRAF V600E mutation, which then warranted treatment with the MEK1 and MEK2 inhibitor, cobimetinib. The patient has achieved a complete response (CR) to a combination of gemcitabine, nab-paclitaxel, and cobimetinib. It has been 16 mo since the start of the treatment, and the patient continues to demonstrate a complete durable response both serologically and radiologically.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/genética , Femenino , Humanos , Quinasas de Proteína Quinasa Activadas por Mitógenos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas p21(ras)/genética
6.
BMJ Case Rep ; 20172017 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-29183892

RESUMEN

A 32-year-old female with stage IV colorectal cancer and metastasis to the liver experienced cardiotoxic reactions after treatment with 5-fluorouracil and its oral prodrug capecitabine even at two-thirds the recommended dose. After careful considerations, the decision was made to attempt capecitabine retrial at a further suboptimal dose with combination chemotherapy where she no longer experienced cardiac events. As a result, the liver tumour shrank and rectal mass stabilised, tumour markers dropped and she underwent surgical resection of both masses. Later there was local recurrence of disease near the previous liver tumour, so the suboptimal capecitabine therapy was restarted without complaint. The patient became a candidate for a NanoKnife procedure, offering a potentially curative therapy. This case report summarises a novel treatment strategy for those patients with advanced colorectal cancer who experience cardiotoxic reactions to fluoropyrimidines, the active agent of gold standard treatment.


Asunto(s)
Antimetabolitos Antineoplásicos/administración & dosificación , Capecitabina/administración & dosificación , Cardiotoxicidad , Neoplasias Colorrectales/tratamiento farmacológico , Fluorouracilo/administración & dosificación , Adulto , Antimetabolitos Antineoplásicos/efectos adversos , Capecitabina/efectos adversos , Cardiotoxicidad/etiología , Neoplasias Colorrectales/patología , Relación Dosis-Respuesta a Droga , Femenino , Fluorouracilo/efectos adversos , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario
7.
J Surg Res ; 216: 65-72, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-28807215

RESUMEN

BACKGROUND: Neoadjuvant treatment is standard for locally advanced esophageal cancer. However, whether the addition of radiation to neoadjuvant regimen improves survival remains unclear. The aim of this study was to compare survival in locally advanced esophageal cancer treated with neoadjuvant chemotherapy versus chemoradiation. MATERIALS AND METHODS: A prospectively maintained database of esophagectomies (1999-2012) was analyzed. We identified 297 patients with locally advanced esophageal cancer that underwent either neoadjuvant chemotherapy (n = 231) or chemoradiation (n = 66) followed by esophagectomy. Pretreatment and pathologic staging were compared to assess response. Overall survival was recorded. RESULTS: Most patients in the chemotherapy and chemoradiation groups had pretreatment stage III disease (66.7% versus 65.2%; P = 0.44). Median follow-up was 79.3 and 64.9 mo for chemotherapy and chemoradiation cohorts, respectively. Complete response rate was higher in chemoradiation than chemotherapy groups (30.3% versus 13.8%; P < 0.001). Overall survival was similar between complete responders in both groups (median not reached versus 121.1 mo; chemotherapy versus chemoradiation). However, partial responders in the chemotherapy cohort had improved median survival (147.2 mo) versus those in the chemoradiation cohort (83.7 mo, P < 0.03). Within the chemotherapy-only group, partial responders had improved survival compared with nonresponders (P = 0.041); however, there was no difference in survival between partial and complete responders (P = 0.36). CONCLUSIONS: In patients undergoing esophagectomy for locally advanced esophageal cancer, neoadjuvant chemotherapy was associated with an equivalent overall survival, when compared with neoadjuvant chemoradiotherapy. Adding neoadjuvant radiation may enhance complete response rates but does not appear to be associated with improved survival.


Asunto(s)
Adenocarcinoma/terapia , Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Esofagectomía , Terapia Neoadyuvante/métodos , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adulto , Anciano , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Quimioradioterapia Adyuvante , Quimioterapia Adyuvante , Bases de Datos Factuales , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/patología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
8.
Mol Pharmacol ; 89(2): 226-32, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26573582

RESUMEN

The metalloid arsenic is a worldwide environmental toxicant, exposure to which is associated with many adverse outcomes. Arsenic is also an effective therapeutic agent in certain disease settings. Arsenic was recently shown to regulate the activity of the Hedgehog (HH) signal transduction pathway, and this regulation of HH signaling was proposed to be responsible for a subset of arsenic's biologic effects. Surprisingly, these separate reports proposed contradictory activities for arsenic, as either an agonist or antagonist of HH signaling. Here we provide in vitro and in vivo evidence that arsenic acts as a modulator of the activity of the HH effector protein glioma-associated oncogene family zinc finger (GLI), activating or inhibiting GLI activity in a context-dependent manner. This arsenic-induced modulation of HH signaling is observed in cultured cells, patients with colorectal cancer who have received arsenic-based therapy, and a mouse colorectal cancer xenograft model. Our results show that arsenic activates GLI signaling when the intrinsic GLI activity is low but inhibits signaling in the presence of high-level GLI activity. Furthermore, we show that this modulation occurs downstream of primary cilia, evidenced by experiments in suppressor of fused homolog (SUFU) deficient cells. Combining our findings with previous reports, we present an inclusive model in which arsenic plays dual roles in GLI signaling modulation: when GLIs are primarily in their repressor form, arsenic antagonizes their repression capacity, leading to low-level GLI activation, but when GLIs are primarily in their activator form, arsenic attenuates their activity.


Asunto(s)
Arsénico/farmacología , Transducción de Señal/fisiología , Factores de Transcripción/biosíntesis , Factores de Transcripción/genética , Transcripción Genética/fisiología , Animales , Femenino , Células HCT116 , Humanos , Ratones , Ratones Desnudos , Células 3T3 NIH , Transducción de Señal/efectos de los fármacos , Factores de Transcripción/antagonistas & inhibidores , Transcripción Genética/efectos de los fármacos , Ensayos Antitumor por Modelo de Xenoinjerto/métodos , Proteína con Dedos de Zinc GLI1
9.
J Gastrointest Cancer ; 45(3): 363-71, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24825822

RESUMEN

In the past decade, the therapeutic potential of arsenic trioxide (ATO) in the treatment of acute promyelocytic leukemia (APL) was recognized. This encouraged other investigators to test the efficacy of ATO in the management of other hematological and solid tumor malignancies. Notably, as a single agent, arsenic trioxide did not benefit patients diagnosed with solid tumors. However, when it was combined with other agents, treatment benefit emerged. In this article, we have summarized the outcome of clinical trials that used arsenic trioxide as a single agent as well as in combination settings in patients diagnosed with solid tumors. We have also reviewed possible additional mechanisms by which ATO may be useful as a chemosensitizer in combination therapy. We hope that our review will encourage clinical investigators to rationally combine ATO with additional chemotherapeutic agents in treating patients diagnosed with solid tumors.


Asunto(s)
Antineoplásicos/uso terapéutico , Arsenicales/uso terapéutico , Neoplasias/tratamiento farmacológico , Óxidos/uso terapéutico , Antineoplásicos/efectos adversos , Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Apoptosis/efectos de los fármacos , Trióxido de Arsénico , Arsenicales/administración & dosificación , Arsenicales/efectos adversos , Arsenicales/farmacología , Encefalopatías/inducido químicamente , Ensayos Clínicos como Asunto , Terapia Combinada , Aprobación de Drogas , Sinergismo Farmacológico , Proteínas Hedgehog/fisiología , Enfermedades Hematológicas/inducido químicamente , Humanos , Medicina Tradicional China , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas de Fusión Oncogénica/antagonistas & inhibidores , Óxidos/administración & dosificación , Óxidos/efectos adversos , Óxidos/farmacología , Radioterapia Adyuvante , Transducción de Señal/efectos de los fármacos , Timidilato Sintasa/antagonistas & inhibidores , Factores de Transcripción/antagonistas & inhibidores , Resultado del Tratamiento , Estados Unidos , United States Food and Drug Administration , Proteína con Dedos de Zinc GLI1
10.
Dig Dis Sci ; 59(6): 1296-301, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24395381

RESUMEN

BACKGROUND: Cryotherapy using liquid nitrogen delivered endoscopically has been used for mucosal ablation of esophageal neoplasia. There are no data for the human esophagus on the depth of injury and effects of this technique. AIM: Prospective study to examine the effect of treatment and depth of injury to the human esophagus of liquid nitrogen spray cryotherapy for subjects with esophageal neoplasia before planned esophagectomy. METHODS: Liquid nitrogen spray cryoablation was performed seven days before scheduled esophagectomy for seven males with esophageal carcinoma. Subjects were assigned to either treatment of four cycles of 10 s each (group 1) or two cycles of 20 s each (group 2) applied to a 2-cm segment of healthy esophagus above the tumor area. Main outcomes measured were: mean depth of injury (mm); surface displaying mucosal ablation, and adverse events. RESULTS: Mucosal destruction was similar for both groups (group 1, 95%; group 2, 93%; p = NS). Deeper injury was observed for group 2; mean depth was 5.4 mm compared with 4.0 mm for group 1. Cryonecrosis reached the submucosa for 60% (12/20) of subjects in group 1 versus 93% (14/15) of subjects in group 2 (p = 0.04, two-tailed Fisher's exact test). No serious adverse events occurred. No perforation was seen in the resected esophagus. CONCLUSION: Mucosal ablation with liquid nitrogen spray cryotherapy was highly effective in inducing mucosal necrosis; the doses assessed had similar effects. Ablation reached the submucosa more often with longer spray time despite fewer treatment cycles.


Asunto(s)
Carcinoma/cirugía , Criocirugía , Neoplasias Esofágicas/cirugía , Esofagectomía , Recolección de Datos , Humanos , Masculino , Membrana Mucosa/patología , Encuestas y Cuestionarios
11.
Ann Surg Oncol ; 20(5): 1660-7, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23456314

RESUMEN

BACKGROUND: There is no consensus on the most effective modality for the treatment of resectable esophageal adenocarcinomas (EAC). We theorized that treatment modality may influence survival differently depending on the stage of disease. METHODS: A single-institution, retrospective examination of resectable EAC between 2000 and 2008 was performed. Resectable EAC were stratified into early disease (stage 2a or less) and late disease (stage 2b or more) based on pretreatment endoscopic ultrasound (EUS). Patients with T4, >N2, and/or distant disease were excluded. RESULTS: A total of 156 patients were included in this study. Most patients were white (97 %), male (83 %), and over 60 years of age (51 %). Patients with early disease on pretreatment EUS exhibited improved overall survival compared to patients with late disease (P < 0.001). Irrespective of treatment modality, there were no significant differences in overall 5-year survival for patients with early or late disease. Early and late disease patients whose disease responded to neoadjuvant chemotherapy (NAC) had significantly improved overall survival compared to nonresponsive disease (P < 0.05). The only negative independent predictors of overall 5-year survival were late stage disease on pretreatment EUS (hazard ratio 2.402, 95 % confidence interval 1.24-4.67, P = 0.01) and late stage disease on final pathological stage (hazard ratio 2.29, 95 % confidence interval 1.22-4.31, P = 0.01). CONCLUSIONS: Our data lack statistical power but reveal no difference in survival with the addition of neoadjuvant therapies to surgery for early or late resectable EAC. However, patients with disease that responded to NAC had improved outcomes at 5 years for both groups. Therefore, the prognosis for patients undergoing NAC may be optimized by immediate surgical resection if neoadjuvant therapies do not result in a dramatic clinical response.


Asunto(s)
Adenocarcinoma/terapia , Neoplasias Esofágicas/terapia , Adenocarcinoma/diagnóstico por imagen , Adenocarcinoma/secundario , Adulto , Quimioradioterapia Adyuvante , Quimioterapia Adyuvante , Endosonografía , Neoplasias Esofágicas/diagnóstico por imagen , Neoplasias Esofágicas/patología , Esofagectomía , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento
12.
Artículo en Inglés | MEDLINE | ID: mdl-24454496

RESUMEN

Achyranthes aspera (family Amaranthaceae) is known for its anticancer properties. We have systematically validated the in vitro and in vivo anticancer properties of this plant. However, we do not know its mode of action. Global gene expression analyses may help decipher its mode of action. In the absence of identified active molecules, we believe this is the best approach to discover the mode of action of natural products with known medicinal properties. We exposed human pancreatic cancer cell line MiaPaCa-2 (CRL-1420) to 34 µ g/mL of LE for 24, 48, and 72 hours. Gene expression analyses were performed using whole human genome microarrays (Agilent Technologies, USA). In our analyses, 82 (54/28) genes passed the quality control parameter, set at FDR ≤ 0.01 and FC of ≥±2. LE predominantly affected pathways of immune response, metabolism, development, gene expression regulation, cell adhesion, cystic fibrosis transmembrane conductance regulation (CFTR), and chemotaxis (MetaCore tool (Thomson Reuters, NY)). Disease biomarker enrichment analysis identified LE regulated genes involved in Vasculitis-inflammation of blood vessels. Arthritis and pancreatitis are two of many etiologies for vasculitis. The outcome of disease network analysis supports the medicinal use of A. aspera, viz, to stop bleeding, as a cure for pancreatic cancer, as an antiarthritic medication, and so forth.

13.
J Surg Res ; 178(2): 623-31, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22682528

RESUMEN

BACKGROUND: The role of neoadjuvant and adjuvant therapy for gastric cancer remains undefined. We compared the outcomes for patients treated with surgery alone or with the addition of adjuvant or neaodjuvant treatment. METHODS: A single-institution, retrospective evaluation of a prospective database of gastric cancer patients treated from 2000 to 2008 was performed. RESULTS: Overall, 173 patients with gastric cancer underwent surgical extirpation. Of the 173 patients, 43% had early-stage disease (less than stage 2) and 57% had late-stage disease (stage 2 or greater; American Joint Committee on Cancer, 2010). The median survival from the date of diagnosis for those treated with neoadjuvant chemotherapy (NAC) (n = 35), adjuvant chemotherapy (n = 21), adjuvant chemoradiotherapy (n = 18), both NAC and adjuvant chemotherapy (n = 11), or surgery alone (n = 88) was 26.3, 17.3, greater than 60, greater than 60, and 50.3 months, respectively. The addition of NAC to surgery was detrimental to survival in those with early-stage disease (P = 0.002) and did not improve survival in those with late-stage disease (P = 0.687). For those with late-stage disease, surgery with adjuvant chemoradiotherapy exhibited the best overall survival compared with surgery alone (P = 0.021) or surgery with adjuvant chemotherapy (P = 0.01). Patients treated with NAC had a greater rate of R0 resection compared with surgery alone (P = 0.049). CONCLUSIONS: NAC for patients with gastric cancer does not significantly improve the overall outcomes for those with late-stage disease and could be detrimental to survival for those with early-stage disease. However, treatment with NAC resulted in an improved rate of R0 resection.


Asunto(s)
Neoplasias Gástricas/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Quimioterapia Adyuvante , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/patología
14.
J Ethnopharmacol ; 142(2): 523-30, 2012 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-22640722

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Achyranthes aspera (Family Amaranthacea) is used for cancer therapy by ayurvedic medical practitioners in India. However, due to the non formal nature of its use, there are no systematic studies validating its medicinal properties. Thus, it's utility as an anti cancer agent remains anecdotal. Earlier, we demonstrated A. aspera to exhibit time and dose-dependent preferential cytotoxicity to cultured human pancreatic cancer cells. In this report we validate in vivo anti tumor properties of A. aspera. MATERIALS AND METHODS: The in vivo anti tumor activity of leaf extract (LE) was tested by intraperitoneal (IP) injections into athymic mice harboring human pancreatic tumor subcutaneous xenograft. Toxicity was monitored by recording changes in behavioral, histological, hematological and body weight parameters. RESULTS: Dosing LE to athymic mice by I.P. injection for 32 days showed no adverse reactions in treated mice. Compared to the control set, IP administration of LE to tumor bearing mice significantly reduced both tumor weight and volume. Gene expression analysis using Real time PCR methods revealed that LE significantly induced caspase-3 mRNA (p<0.001) and suppressed expression of the pro survival kinase Akt-1 (p<0.05). TUNEL assay and immunohistochemistry confirmed apoptosis induction by activation of caspase-3 and inhibiting Akt phosphorylation in treated sets. These results are in agreement with RT PCR data. CONCLUSION: Taken together, these data suggest A. aspera to have potent anti cancer property.


Asunto(s)
Achyranthes , Antineoplásicos Fitogénicos/uso terapéutico , Apoptosis/efectos de los fármacos , Neoplasias Pancreáticas/tratamiento farmacológico , Fitoterapia , Extractos Vegetales/uso terapéutico , Animales , Antineoplásicos Fitogénicos/farmacología , Caspasa 3/genética , Caspasa 3/metabolismo , Expresión Génica/efectos de los fármacos , Humanos , Inyecciones Intraperitoneales , Medicina Ayurvédica , Ratones , Ratones Desnudos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Fosforilación , Extractos Vegetales/farmacología , Hojas de la Planta , Proteínas Proto-Oncogénicas c-akt/metabolismo , ARN Mensajero/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
15.
Oncol Rep ; 27(1): 246-9, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21947036

RESUMEN

Thymidylate synthase (TS) gene contains 28-bp polymorphic sequence and 6-bp insert at the 5'- and 3'-untranslated region, respectively. We investigated the role of these two polymorphic traits on TS mRNA expression in nine different cultured human cancer cell lines in vitro. Three cell lines each were 2R/2R, 2R/3R and 3R/3R genotypes. Six of the nine cell lines tested homozygous for the presence of 6-bp insert (+6/+6) and the rest three lacked this insert (-6/-6). TS expression analyses associated homozygous three repeats (3R/3R) to higher TS expression.


Asunto(s)
Regiones no Traducidas 5'/genética , Regulación de la Expresión Génica/genética , Neoplasias/genética , Timidilato Sintasa/genética , Secuencia de Bases , Línea Celular Tumoral , Expresión Génica , Genotipo , Humanos , Técnicas In Vitro , Datos de Secuencia Molecular , Polimorfismo Genético , Polimorfismo de Longitud del Fragmento de Restricción , ARN Mensajero , Reacción en Cadena en Tiempo Real de la Polimerasa , Timidilato Sintasa/biosíntesis
16.
Jpn J Clin Oncol ; 41(4): 469-76, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21258083

RESUMEN

OBJECTIVE: A complete pathologic response to neoadjuvant chemotherapy, without the use of radiation, has infrequently been reported in operable chemo-naïve stage III esophageal adenocarcinoma patients. METHODS: Twenty-nine eligible patients were enrolled in the study. Neoadjuvant therapy consisted of 5-fluorodeoxyuridine, leucovorin, oxaliplatin and docetaxel and was administered in two 4-week cycles. Following therapy, patients underwent surgical resection. Those patients having residual disease were offered adjuvant chemotherapy. Patients having a complete pathologic response were not offered any further chemotherapy. RESULTS: Twenty-four out of 29 patients finished neoadjuvant therapy and underwent curative esophagectomy. Two patients were declared inoperable after treatment, and three patients died prior to surgery. The median follow-up on all patients was 20.2 months. Median progression-free survival and median overall survival were 13.6 and 21.4 months, respectively. Clinical response to neoadjuvant chemotherapy was seen in 21 out of 29 patients (72.4%). Complete pathologic response with neoadjuvant chemotherapy was seen in 4 out of 24 patients (16.7%). Those four patients have been alive and progression-free for 20-37 months. Grade 3-4 toxicities occurred in 16 of the 29 patients during neoadjuvant therapy. Grade 3-4 toxicities were seen in 6 out of 14 patients during adjuvant therapy. (18)F-fluorodeoxyglucose-positron emission tomography standardized uptake values of ≥8 correlated with better progression-free survival. CONCLUSION: 5-Fluorodeoxyuridine, leucovorin, oxaliplatin and docetaxel regimen is active in patients with esophageal adenocarcinoma. Toxicity profiles are manageable. Neoadjuvant chemotherapy allowed achievement of complete pathologic response without radiation. (18)F-fluorodeoxyglucose-positron emission tomography standardized uptake values might be prognostic.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias Esofágicas/tratamiento farmacológico , Esofagectomía , Terapia Neoadyuvante/métodos , Adenocarcinoma/patología , Adenocarcinoma/cirugía , Anciano , Anciano de 80 o más Años , Antimetabolitos Antineoplásicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Docetaxel , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/cirugía , Esofagectomía/métodos , Femenino , Floxuridina/administración & dosificación , Estudios de Seguimiento , Gastrectomía , Humanos , Estimación de Kaplan-Meier , Leucovorina/administración & dosificación , Metástasis Linfática , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Compuestos Organoplatinos/administración & dosificación , Oxaliplatino , Taxoides/administración & dosificación , Factores de Tiempo , Resultado del Tratamiento
18.
Anticancer Res ; 30(4): 1149-56, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20530421

RESUMEN

Resistance to chemotherapy is a major issue in treating malignant diseases. 5-Fluorouracil (5-FU) is the drug of choice in managing colorectal cancer (CRC) patients. However, 5-FU resistance leads to eventual treatment failure. Therefore, delaying or reversing the onset of 5-FU resistance will benefit these terminally ill patient populations. A metabolite of 5-FU irreversibly binds thymidylate synthase (TS) thus inhibiting its activity. Many studies demonstrated that these resistant patients had an increased intratumoral TS level. We used TS-siRNA to reduce TS and resensitize HT29FU CRC cells back to this uracil analogue. We exposed the CRC cell line HT29 to an increasing concentration of 5-FU or 5-fluorouridine (FUR) and established a derivative cell line (HT29FU and HT29FUR). Using real-time polymerase chain reaction (PCR) and Western immunodetection assays, we analyzed the expression of TS and p53 mRNA and protein in control and experimental groups. Cytotoxicity to 5-FU was determined by reduction of 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT assay) or trypan blue dye exclusion assay. The HT29FU and HT29FUR cells have a distinct morphology: they are generally asteroid shaped. The half maximal inhibitory concentration (IC(50)) values for the resistant cell line for 5-FU is over 148 microM compared to 5 microM for the sensitive parental cell line. The resistant cell lines expressed more of TS and less of p53. TS-siRNA suppressed TS only. Other pathways were not significantly altered. It also marginally (20%) re-sensitized resistant cells to 5-FU. Restoration of partial sensitivity to 5-FU by TS-siRNA reiterates the primacy of the DNA synthesis pathway in 5-FU mode of action. We speculate that the short half-life of the transiently transfected siRNA may contribute to the marginal restoration of sensitivity. By integrating TS-siRNA expression vector into the genome and regulating its expression, we may be able to reverse 5-FU resistance and make the cells as sensitive as the parental cell line.


Asunto(s)
Neoplasias Colorrectales/tratamiento farmacológico , Fluorouracilo/farmacología , Pirimidinas/farmacología , Timidilato Sintasa/biosíntesis , Proteína p53 Supresora de Tumor/antagonistas & inhibidores , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Resistencia a Antineoplásicos , Inducción Enzimática/efectos de los fármacos , Células HT29 , Humanos , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Timidilato Sintasa/genética , Proteína p53 Supresora de Tumor/metabolismo
19.
Anticancer Res ; 30(4): 1157-62, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20530422

RESUMEN

Identification of new agents with antitumor activity in chemoresistant tumors is urgently needed for the treatment of colorectal cancer. Arsenic trioxide (As(2)O(3)), a Food and Drug Administration (FDA) approved drug is successfully being used to treat acute promyelocytic leukemia (APL). Several clinical trials also suggest its ineffectiveness on solid tumors. We proposed that arsenic trioxide may be used as chemosensitizer, especially to 5-fluorouracil (5-FU). The effect of arsenic trioxide on cell proliferation of 5-FU-sensitive and -resistant HT29 colorectal cancer cells in vitro was tested by trypan blue dye exclusion assay, 2, 3-bis(2-methoxy-4-nitro-5-sulfophenyl)-S-[(phenylamino) carbonyl]-2H-tetrazolium hydroxide (XTT) cell proliferation assay and cell cycle analysis using flow cytometry. Gene expression was analyzed using real-time polymerase chain reaction (PCR) and Western blot methods. There was a dose-dependent increase in cell detachment and proliferation in HT29 and HT29FU cells. As a single agent, arsenic trioxide also down-regulated thymidylate synthase (TS) expression without affecting the expression of some other genes analyzed in the above cell lines. Combination of arsenic trioxide and 5-FU increased cytotoxicity. In vitro data show that as a single agent, arsenic trioxide down-regulated TS expression in HT29 cells. Addition of 5-FU to these sensitized cells increased cytotoxicity. These findings open up a possibility to use arsenic trioxide as a chemosensitizer in combination therapy.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Arsenicales/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/enzimología , Fluorouracilo/farmacología , Óxidos/farmacología , Timidilato Sintasa/antagonistas & inhibidores , Trióxido de Arsénico , Arsenicales/administración & dosificación , Western Blotting , Resistencia a Antineoplásicos , Sinergismo Farmacológico , Fluorouracilo/administración & dosificación , Expresión Génica/efectos de los fármacos , Células HT29 , Humanos , Óxidos/administración & dosificación , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Timidilato Sintasa/biosíntesis , Timidilato Sintasa/genética , Proteína p53 Supresora de Tumor/biosíntesis , Proteína p53 Supresora de Tumor/genética
20.
J Ethnopharmacol ; 131(1): 78-82, 2010 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-20541002

RESUMEN

AIMS OF THE STUDY: Achyranthes aspera (Family: Amaranthacea) is a medicinal plant used as an anti-cancer agent in ayurveda, a traditional system of medicine practiced in subcontinental India. The aim of the study was to systematically investigate the anti-proliferative properties of Achyranthes aspera leaves extracted in methanol (LE) on human cancer cells in vitro. MATERIALS AND METHODS: We tested time, dose dependent and specific anti-proliferative activity of LE by clonogenic cell survival assay on human cancer and normal epithelial cell lines in vitro. We further investigated its effect on the expression of metastatic and angiogenic genes by real time polymerase chain reaction. On silica gel column, we carried out initial fractionation analysis. RESULTS: LE exhibited time and dose dependent cytotoxicity on several tumor cells. Compared to cancer cells of colon, breast, lung and prostate origin, pancreatic cancer cells were significantly more sensitive to LE. Preliminary mechanistic studies suggested that LE selectively suppressed the transcription of metalloproteases (MMP-1 and -2), inhibitors of MMPs (TIMP-2) and angiogenic factors (VEGF-A and VEGF-B). Fractionation of LE on methanol equilibrated silica gel column resolved into three fractions of which fraction (F 3) was found to be enriched with anti-proliferative activity. CONCLUSION: Methanolic extract of Achyranthes aspera contains potent anti-proliferative compound with specific activity against pancreatic cancer. Further studies are needed to confirm the in vivo anti-tumorigenicity and subsequent chemical characterization of the active molecule(s).


Asunto(s)
Achyranthes , Antineoplásicos Fitogénicos/uso terapéutico , Inhibidores de Crecimiento/uso terapéutico , Neoplasias Pancreáticas , Extractos Vegetales/uso terapéutico , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular , Línea Celular Tumoral , Inhibidores de Crecimiento/aislamiento & purificación , Células HT29 , Humanos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/patología , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta
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