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1.
Front Oncol ; 13: 1304457, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38322288

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-34915443

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-34901697

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-34667063

RESUMO

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.


Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/genética , Feminino , Humanos , Quinases de Proteína Quinase Ativadas por Mitógeno , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética
6.
BMJ Case Rep ; 20172017 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-29183892

RESUMO

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.


Assuntos
Antimetabólitos Antineoplásicos/administração & dosagem , Capecitabina/administração & dosagem , Cardiotoxicidade , Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/administração & dosagem , Adulto , Antimetabólitos Antineoplásicos/efeitos adversos , Capecitabina/efeitos adversos , Cardiotoxicidade/etiologia , Neoplasias Colorretais/patologia , Relação Dose-Resposta a Droga , Feminino , Fluoruracila/efeitos adversos , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/secundário
7.
J Surg Res ; 216: 65-72, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28807215

RESUMO

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.


Assuntos
Adenocarcinoma/terapia , Carcinoma de Células Escamosas/terapia , Neoplasias Esofágicas/terapia , Esofagectomia , Terapia Neoadjuvante/métodos , Adenocarcinoma/mortalidade , Adenocarcinoma/patologia , Adulto , Idoso , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Quimiorradioterapia Adjuvante , Quimioterapia Adjuvante , Bases de Dados Factuais , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento
8.
Mol Pharmacol ; 89(2): 226-32, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26573582

RESUMO

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.


Assuntos
Arsênio/farmacologia , Transdução de Sinais/fisiologia , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Transcrição Gênica/fisiologia , Animais , Feminino , Células HCT116 , Humanos , Camundongos , Camundongos Nus , Células NIH 3T3 , Transdução de Sinais/efeitos dos fármacos , Fatores de Transcrição/antagonistas & inibidores , Transcrição Gênica/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto/métodos , Proteína GLI1 em Dedos de Zinco
9.
J Gastrointest Cancer ; 45(3): 363-71, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24825822

RESUMO

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.


Assuntos
Antineoplásicos/uso terapêutico , Arsenicais/uso terapêutico , Neoplasias/tratamento farmacológico , Óxidos/uso terapêutico , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Apoptose/efeitos dos fármacos , Trióxido de Arsênio , Arsenicais/administração & dosagem , Arsenicais/efeitos adversos , Arsenicais/farmacologia , Encefalopatias/induzido quimicamente , Ensaios Clínicos como Assunto , Terapia Combinada , Aprovação de Drogas , Sinergismo Farmacológico , Proteínas Hedgehog/fisiologia , Doenças Hematológicas/induzido quimicamente , Humanos , Medicina Tradicional Chinesa , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Fusão Oncogênica/antagonistas & inibidores , Óxidos/administração & dosagem , Óxidos/efeitos adversos , Óxidos/farmacologia , Radioterapia Adjuvante , Transdução de Sinais/efeitos dos fármacos , Timidilato Sintase/antagonistas & inibidores , Fatores de Transcrição/antagonistas & inibidores , Resultado do Tratamento , Estados Unidos , United States Food and Drug Administration , Proteína GLI1 em Dedos de Zinco
10.
Dig Dis Sci ; 59(6): 1296-301, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24395381

RESUMO

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.


Assuntos
Carcinoma/cirurgia , Criocirurgia , Neoplasias Esofágicas/cirurgia , Esofagectomia , Coleta de Dados , Humanos , Masculino , Mucosa/patologia , Inquéritos e Questionários
11.
Ann Surg Oncol ; 20(5): 1660-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23456314

RESUMO

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.


Assuntos
Adenocarcinoma/terapia , Neoplasias Esofágicas/terapia , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/secundário , Adulto , Quimiorradioterapia Adjuvante , Quimioterapia Adjuvante , Endossonografia , Neoplasias Esofágicas/diagnóstico por imagem , Neoplasias Esofágicas/patologia , Esofagectomia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento
12.
Artigo em Inglês | MEDLINE | ID: mdl-24454496

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-22682528

RESUMO

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.


Assuntos
Neoplasias Gástricas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Quimioterapia Adjuvante , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Estadiamento de Neoplasias , Neoplasias Gástricas/mortalidade , Neoplasias Gástricas/patologia
14.
J Ethnopharmacol ; 142(2): 523-30, 2012 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-22640722

RESUMO

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.


Assuntos
Achyranthes , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Neoplasias Pancreáticas/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Antineoplásicos Fitogênicos/farmacologia , Caspase 3/genética , Caspase 3/metabolismo , Expressão Gênica/efeitos dos fármacos , Humanos , Injeções Intraperitoneais , Ayurveda , Camundongos , Camundongos Nus , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Fosforilação , Extratos Vegetais/farmacologia , Folhas de Planta , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Mensageiro/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Oncol Rep ; 27(1): 246-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21947036

RESUMO

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.


Assuntos
Regiões 5' não Traduzidas/genética , Regulação da Expressão Gênica/genética , Neoplasias/genética , Timidilato Sintase/genética , Sequência de Bases , Linhagem Celular Tumoral , Expressão Gênica , Genótipo , Humanos , Técnicas In Vitro , Dados de Sequência Molecular , Polimorfismo Genético , Polimorfismo de Fragmento de Restrição , RNA Mensageiro , Reação em Cadeia da Polimerase em Tempo Real , Timidilato Sintase/biossíntese
16.
Jpn J Clin Oncol ; 41(4): 469-76, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21258083

RESUMO

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.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Esofágicas/tratamento farmacológico , Esofagectomia , Terapia Neoadjuvante/métodos , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Idoso , Idoso de 80 Anos ou mais , Antimetabólitos Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimioterapia Adjuvante , Intervalo Livre de Doença , Docetaxel , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Feminino , Floxuridina/administração & dosagem , Seguimentos , Gastrectomia , Humanos , Estimativa de Kaplan-Meier , Leucovorina/administração & dosagem , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Compostos Organoplatínicos/administração & dosagem , Oxaliplatina , Taxoides/administração & dosagem , Fatores de Tempo , Resultado do Tratamento
18.
Anticancer Res ; 30(4): 1149-56, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20530421

RESUMO

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.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Fluoruracila/farmacologia , Pirimidinas/farmacologia , Timidilato Sintase/biossíntese , Proteína Supressora de Tumor p53/antagonistas & inibidores , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Resistencia a Medicamentos Antineoplásicos , Indução Enzimática/efeitos dos fármacos , Células HT29 , Humanos , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Timidilato Sintase/genética , Proteína Supressora de Tumor p53/metabolismo
19.
Anticancer Res ; 30(4): 1157-62, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20530422

RESUMO

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.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Arsenicais/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/enzimologia , Fluoruracila/farmacologia , Óxidos/farmacologia , Timidilato Sintase/antagonistas & inibidores , Trióxido de Arsênio , Arsenicais/administração & dosagem , Western Blotting , Resistencia a Medicamentos Antineoplásicos , Sinergismo Farmacológico , Fluoruracila/administração & dosagem , Expressão Gênica/efeitos dos fármacos , Células HT29 , Humanos , Óxidos/administração & dosagem , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Timidilato Sintase/biossíntese , Timidilato Sintase/genética , Proteína Supressora de Tumor p53/biossíntese , Proteína Supressora de Tumor p53/genética
20.
J Ethnopharmacol ; 131(1): 78-82, 2010 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-20541002

RESUMO

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).


Assuntos
Achyranthes , Antineoplásicos Fitogênicos/uso terapêutico , Inibidores do Crescimento/uso terapêutico , Neoplasias Pancreáticas , Extratos Vegetais/uso terapêutico , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular , Linhagem Celular Tumoral , Inibidores do Crescimento/isolamento & purificação , Células HT29 , Humanos , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/patologia , Extratos Vegetais/isolamento & purificação , Folhas de Planta
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