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1.
Blood ; 96(7): 2385-90, 2000 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-11001888

RESUMEN

The safety and efficacy of administering ex vivo expanded peripheral blood progenitor cells (PBPC) to patients with breast cancer who undergo high-dose chemotherapy and PBPC transplantation was investigated. Unselected PBPC were cultured in gas-permeable bags containing 1-L serum-free media, granulocyte colony-stimulating factor, stem cell factor, and pegylated megakaryocyte growth and development factor for 9 days. Cell dose cohorts were assigned to have between 2 and 24 x 10(9) PBPC cultured at 1, 2, or 3 x 10(6) cells/mL. Twenty-four patients received high-dose chemotherapy followed by infusion of the cultured PBPC and at least 5 x 10(6) CD34(+) uncultured cryopreserved PBPC per kilogram. No toxicities resulted from infusions of the ex vivo expanded PBPC. The study patients had shorter times to neutrophil (P =.0001) and platelet (P =.01) recovery and fewer red cell transfusions (P =.02) than 48 historical controls who received the same conditioning regimen and posttransplantation care and at least 5 x 10(6) CD34(+) PBPC per kilogram. Improvements in all these endpoints were significantly correlated with the expanded cell dose. Nine of 24 (38%) patients recovered neutrophil counts above 500/microL by day 5 or 6 after transplantation, whereas none of the controls had neutrophil recovery before the eighth day. Seven (29%) patients had neutropenia for 3 or fewer days, and 9 (38%) patients did not experience neutropenic fevers or require broad-spectrum antibiotics. Therefore, ex vivo expanded PBPC are capable of ameliorating posttransplantation neutropenia, thrombocytopenia, and anemia in patients receiving high-dose chemotherapy.


Asunto(s)
Anemia/prevención & control , Neoplasias de la Mama/terapia , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/fisiología , Neutropenia/prevención & control , Trombocitopenia/prevención & control , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/cirugía , Recuento de Células , Células Cultivadas , Medio de Cultivo Libre de Suero , Citometría de Flujo , Factor Estimulante de Colonias de Granulocitos/farmacología , Células Madre Hematopoyéticas/inmunología , Humanos , Inmunofenotipificación , Tiempo de Internación , Transfusión de Plaquetas , Factor de Células Madre/farmacología , Trombopoyetina/farmacología
2.
Pancreas ; 18(2): 111-6, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10090407

RESUMEN

Often the diagnosis of pancreas cancer needs to be established from limited cytology specimens or small biopsies. Most ductal adenocarcinomas are histologically well to moderately differentiated and mimicked closely by pancreatitis, and therefore the microscopic diagnosis can be difficult. In addition, there appears to be significant heterogeneity in the outcome of the patients with pancreatic cancer, which cannot be predicted accurately by current prognosticators such as the grade and stage of the tumor. Therefore, there is need for methods that can be used as adjuncts to routine diagnostic and prognostic parameters. This study was designed to test the utility of the fluorescent in situ hybridization (FISH) method in identifying the molecular alterations, particularly the ones that have been detected with relatively high frequency in pancreas cancer. Formalin-fixed and paraffin-embedded tissues of 10 cases were enumerated for chromosome 7, 8, 17, 18, and 20 copy numbers by using alpha-satellite probes, and for c-myc by using a gene-specific probe. The number of signals per nucleus (reflecting chromosomal copy number and status of c-myc amplification) were counted in more than two areas containing 50-500 cells. Because of tumor heterogeneity, monosomy (loss of one chromosome copy) was defined arbitrarily as one signal in >25% of nuclei. C-myc amplification was defined as more than two gene copies in >20% of the cells. The most frequent signal losses were found in chromosomes 8 (four of 10 cases) and chromosome 17 (four of 10), followed by 20 (three of 10) and 18 (two of 10). No loss of chromosome 7 was detected. In contrast, gains in chromosome copy number were identified in only one of 10 tumors, which showed gain of both chromosome 7 and 18. Amplification of c-myc gene was detected in two of 10 cases, but neither of the two had aneuploidy for chromosome 8, where the c-myc gene is located. In addition, loss in c-myc signal was observed in one case that also showed loss of chromosome 8 copy number. FISH can be used to detect chromosomal changes in pancreatic cancer; abundance of lytic enzymes in this organ is not an impediment for the applicability of this technique. Therefore it can potentially be used in the future as an adjunct to the conventional diagnostic and prognostic markers. This study confirms that loss of chromosomes, particularly chromosomes 17 and 18, which carry the p53 and DCC genes, are common in pancreas cancer. Chromosome 20 is also frequently lost. In addition, in this study, alterations of chromosome 8, which is seen commonly in prostatic adenocarcinoma but has not been previously documented in pancreatic cancer, also was detected in five of 10 tumors. Furthermore, amplification of the c-myc gene, which is located in chromosome 8, was found in the two of the remaining five cases. Further studies are needed to confirm this high incidence of chromosome 8 and c-myc alterations and their possible role in the pathogenesis of pancreatic adenocarcinoma.


Asunto(s)
Adenocarcinoma/diagnóstico , Hibridación Fluorescente in Situ , Conductos Pancreáticos/patología , Neoplasias Pancreáticas/diagnóstico , Adenocarcinoma/genética , Adenocarcinoma/patología , Deleción Cromosómica , Cromosomas Humanos/genética , Dosificación de Gen , Genes myc/genética , Genes p53/genética , Humanos , Inmunohistoquímica , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Poliploidía
3.
Pancreas ; 16(2): 107-13, 1998 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-9510131

RESUMEN

New innovations are needed for the treatment of pancreatic cancer, as current treatments do not offer significant improvements in overall survival. p21WAF1--a tumor suppressor gene--acts as a downstream effector of p53 function and mediates G1 cell cycle arrest by inhibiting cyclin-dependent kinases, which promote cell growth. p21 expression has also been shown to increase more than 20-fold in senescent cells in culture. The replication-defective recombinant adenoviral system (rAd), a major innovation in gene transfer technology, has recently been used in gene therapy applications for various malignancies but not for pancreas cancer. In this study we used rAd-p21 in cell growth inhibition studies of pancreatic tumor cell lines in vitro to explore its potential as a prospective gene therapy for pancreatic adenocarcinoma. We studied two pancreatic cell lines in culture, HPAC and Hs766T. HPAC revealed higher endogenous levels of p21 gene expression at the protein and RNA levels compared to Hs766T. p21 induction was tested using different doses of rAd-p21 to establish an optimum dose for significant induction of p21 gene expression. Tumor cell growth in culture following rAd-p21 infection was also analyzed in both cell lines. HPAC and Hs766T cell lines showed a significant dose-dependent increase in p21 protein expression when infected with rAd-p21. Both cell lines showed significant growth arrest, but Hs766T showed less cell growth inhibition than HPAC cells. Flow cytometric cell cycle analysis of rAd-p21-infected cells showed a statistically significant increase in the number of cells in G0/G1 in HPAC cells. Similar results were also obtained in Hs766T cells, however, the data were not statistically significant. In conclusion, pancreatic tumor cell growth can be inhibited by rAd-p21 in vitro, with significant numbers of tumor cells reverting from S to G0/G1. Thus rAd-p21 may be effective as a candidate gene therapy for pancreatic cancer and should be further evaluated with in vivo studies.


Asunto(s)
Adenocarcinoma/patología , Adenoviridae/genética , Ciclinas/genética , Técnicas de Transferencia de Gen , Neoplasias Pancreáticas/patología , Adenocarcinoma/metabolismo , Northern Blotting , Western Blotting , Ciclo Celular , División Celular , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Ciclinas/fisiología , Citometría de Flujo , Expresión Génica , Humanos , Neoplasias Pancreáticas/metabolismo , ARN Mensajero/metabolismo , Células Tumorales Cultivadas
4.
Pancreas ; 16(1): 19-25, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9436858

RESUMEN

Adenocarcinoma of the pancreas is currently the fifth leading cause of death in the United States. It remains generally incurable by available treatment modalities. We report here on the characterization of a permanent pancreatic cell line (KCI-MOH1), established as a xenograft in severe combined immune deficient (SCID) mice, from a 74 year-old African American male patient diagnosed with pancreatic cancer. Sections from paraffin-embedded tumors excised from SCID mice revealed typical adenocarcinoma of the pancreas. Karyotypic analysis of cultured cells derived from tumors grown in SCID mice revealed a male karyotype with multiple clonal aberrations: 42, XY, add (3)(p11.2), der(7) t(7;12) (p22;q12), -10, -12, add (14)(p11), -18, add (20)(q13)-22/84, idemx2. Immunostaining of KCI-MOH1 tissues shows strong expression of p53 and p21 proteins. The xenograft model was established by transplanting the KCI-MOH1 cells subcutaneously (s.c.) in SCID mice. When the s.c. tumor was transplanted in vivo to other SCID mice, the success rate was 100%, with a doubling time of 8.5 days. The SCID mouse xenograft model was used to test the efficacy of selected standard chemotherapeutic drugs (taxol, gemcitabine, 5-fluorouracil, and Ara-C) and novel biological agents (Bryostatin 1 and Auristatin-PE). Results show that gemcitabine, Ara-C, and Bryostatin 1 were active against KCI-MOH1. The xenograft described herein can be used as an animal model to facilitate the development of novel therapeutic agents against human pancreatic cancers.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Modelos Animales de Enfermedad , Neoplasias Pancreáticas/tratamiento farmacológico , Adenocarcinoma/genética , Anciano , Animales , Antineoplásicos/uso terapéutico , Aberraciones Cromosómicas , Deleción Cromosómica , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Ciclinas/genética , Expresión Génica , Genes p53/genética , Humanos , Cariotipificación , Masculino , Ratones , Ratones SCID , Trasplante de Neoplasias , Neoplasias Pancreáticas/genética , Trasplante Heterólogo , Células Tumorales Cultivadas
5.
J Hepatobiliary Pancreat Surg ; 5(3): 269-72, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9880774

RESUMEN

Multiple genetic alterations, several of which may be important prognostic markers, characterize the development of cancer in pancreas. We review our findings from previously published studies with regard to molecular alterations associated with survival differences in patients treated with conventional radiation and chemotherapies used as adjuvant or palliative therapy. K-ras-negative patients with pancreas cancer show improved survival with radiation therapy compared to K-ras-positive patients with pancreas cancer. p53 expression is associated with shorter survival when compared to no p53 expression in pancreas cancer patients treated with radiation therapy or chemotherapy. Pancreas cancer patients whose tumors express p21 show significant survival advantages when treated with chemotherapy or radiation therapy. An inverse relationship is observed with respect to p21 and p53 expression and clinical stage. Although stage and surgical resectability remain the most important variables with respect to pancreas cancer survival, these findings suggest promising opportunities for gene therapies designed to enhance p21 expression or restore wild-type K-ras or p53 function in pancreatic tumors.


Asunto(s)
Adenocarcinoma/genética , Ciclinas , Inhibidores Enzimáticos , Regulación Neoplásica de la Expresión Génica , Genes ras , Neoplasias Pancreáticas/genética , Proteína p53 Supresora de Tumor , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/mortalidad , Adenocarcinoma/radioterapia , Estudios de Casos y Controles , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Humanos , Mutación , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/radioterapia , Estudios Retrospectivos , Análisis de Supervivencia
6.
Cancer ; 80(3): 372-81, 1997 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-9241070

RESUMEN

BACKGROUND: Wild-type p53 protein activates the WAF1/CIP-1 (p21) gene, leading to G1 arrest after DNA damage. The authors investigated the relation of p21 and p53 expression in pancreatic adenocarcinomas to disease stage, overall patient survival, and survival when chemotherapy or radiation therapy was given. METHODS: Paraffin embedded tissue sections of 75 ductal adenocarcinomas of the pancreas were immunostained for p53 and p21. Nuclear expression was scored as absent, focal (<10%), moderate (10-50%), or strong or diffuse (>50%). RESULTS: The median survival of patients whose pancreatic tumors expressed the p21 protein (43 of 75 cases, 57%) was better than that for patients whose tumors were p21 negative (32 of 75 cases, 43%) (median survival, 13.5 vs. 9.8 months, respectively; P = 0.23). No difference in survival was found with regard to p53 protein expression (43 of 75 cases, 57%); however, strong p53 expression was significantly associated with advanced disease stage (70% in Stage IV vs. 13-28% in lower stages). Expression of p21 correlated with earlier clinical stage. Stage specific comparisons showed a trend toward increased survival among p21 positive tumor patients diagnosed at clinical Stages I and III but not among those diagnosed at Stage IV. Adjuvant chemotherapy or radiation improved survival significantly if tumors expressed p21 or no p53. CONCLUSIONS: Expression of p21 is significantly associated with earlier clinical stage in pancreatic adenocarcinoma, perhaps accounting for the better survival observed in this patient group than among those whose tumors were p21 negative. Improved survival with either chemotherapy or radiation therapy was observed for patients whose tumors were p21 positive or p53 negative.


Asunto(s)
Adenocarcinoma/metabolismo , Ciclinas/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias Pancreáticas/metabolismo , Proteína p53 Supresora de Tumor/metabolismo , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Adenocarcinoma/terapia , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Humanos , Inmunohistoquímica , Análisis Multivariante , Estadificación de Neoplasias , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Neoplasias Pancreáticas/terapia , Análisis de Supervivencia
7.
Int J Pancreatol ; 21(3): 225-34, 1997 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9322121

RESUMEN

CONCLUSION: In our series of 81 cases, a history of family cancer was present in 52% of patients (42/81) with pancreatic cancer. Nine percent (7/81)had a family history of pancreatic cancer. Our studies suggest a possible relationship of family cancer history to the expression of p53 and p21WAF in pancreatic tumors, but show no relationship to the expression of HER-2/neu or to the prevalence of K-ras mutations. A lower incidence of p53 expression observed in patients with a family history of cancer suggests normal p53 protein is present in a majority of patients who develop pancreatic tumors related to other--as yet unidentified-inherited or familial risk factors. There was no significant difference in survival of pancreas cancer patients with and without a family history of cancer. However, survival in pancreas cancer patients may be influenced (improved) by p21WAF-1 expression. BACKGROUND: Pancreas cancer is the fifth leading cause of cancer deaths (27,800 deaths/yr) in the United States. Various risk factors, including cigarette smoking, high-fat diet, DDT exposure, chronic pancreatitis, and diabetes mellitus, have been associated with pancreatic carcinoma. A few studies have suggested a genetic predisposition or increased risk for pancreatic cancer within families, but the exact etiology is largely unknown. In a series of 81 patients with pancreatic carcinoma, we analyzed the status of K-ras gene mutations and the expression of P21WAF-1, p53, and HER-2/neu protein to identify possible molecular associations in pancreas cancer cases of these molecular markers to family histories of cancer and pancreas cancer. METHODS: Paraffin-embedded tissue sections from 81 cases of pancreatic adenocarcinoma were used for DNA extraction and immunohistochemical staining. K-ras mutation was studied by single-stranded conformation polymorphism (SSCP) and slot-blot allele-specific oligonucleotide (ASO) hybridization of PCR-amplified DNA product. Overexpression (aberrant expression) of p53, p21WAF-1, and HER-2/neu was documented by scoring nuclear localized p53, p21WAF-1 protein and cell membrane expression of HER-2/neu after immunostaining with gene product-specific monoclonal antibodies (MAbs). RESULTS: Forty-two (42) of 81 patients studied in this series had a history of cancer in their families (52%). Seven of those 42 had a history of pancreatic carcinoma (17% or 9% of total cases). The incidence of K-ras mutation and the expression of p21WAF-1 and HER-2/neu in patient groups with and without a family history of cancer was not statistically different (83 vs 74%, p = 0.416; 57 vs 41%, p = 0.184; and 83 vs 81%, p = 1.000, respectively). However, the incidence of p53 expression was significantly lower in patients with a family history of cancer (40 vs 72%, p = 0.007). There was no statistical difference in survival of patients with a family history of cancer in relation to either K-ras mutation, p53 expression, p21, or HER-2/neu expression. However, patients lacking a family history of cancer showed improved survival trends in relation to p21 expression (median survival of 16 vs 8 mo, p = 0.029).


Asunto(s)
Adenocarcinoma/genética , Genes erbB-2 , Genes p53 , Genes ras , Neoplasias Pancreáticas/genética , Mutación Puntual , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad
8.
Int J Pancreatol ; 21(2): 127-43, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9209954

RESUMEN

CONCLUSION: This study could not attribute survival differences to the coincident acquisition of two common genetic alterations, K-ras mutation and p53 overexpression in pancreatic adenocarcinoma patients. Additionally, our data indicate the converse to be true: Those patients lacking both K-ras mutation and aberrant p53 expression showed the shortest survival when compared with cases showing either alteration or both. This study also showed the negative effect of K-ras mutation and p53 expression on pancreas cancer patients' survival after treatment with either radiation therapy or chemotherapy. BACKGROUND: Mutations of the oncogene K-ras at codon 12 are reported to be the most common genetic alteration in pancreatic carcinoma, whereas either overexpression or mutation of the tumor suppressor p53 gene is considered the most common genetic alteration in neoplasia of all types. p53 overexpression has been attributed to survival differences in pancreatic carcinoma, but such association is still controversial. No studies have fully documented the combined incidence of K-ras and p53 alterations in pancreatic adenocarcinoma, or their combined effect on patient survival in a large case series. The influence of radiation or chemotherapy in groups showing both, either, or neither mutation is also undocumented. METHODS: Paraffin-embedded tissue sections from 76 cases of pancreatic adenocarcinoma were cut for DNA extraction for K-ras analysis and immunohistochemical staining for aberrant p53 expression. K-ras mutation was determined by single-strand conformation polymorphism (SSCP) and slot-blot allele-specific oligonucleotide (ASO) hybridization of PCR-amplified DNA product p53 expression was scored on the basis of percent nuclear staining with the MAb DO7. RESULTS: Sixty-four of 76 cases (84%) showed K-ras mutation, p53 expression, or both, K-ras was mutated in 55 of 76 cases (72%). p53 was expressed in 33 of 76 cases (43%). Twenty-four of 76 cases (31%) showed both K-ras mutation and p53 expression. The presence of both alterations was not related to significant differences in tumor grade, stage, or survival compared to either alteration alone. A sizable subset (16% of cases) lacked either alteration, and surprisingly, this group showed the shortest median survival compared to those with K-ras mutation, p53 expression, or both (p = 0.024). Patients whose tumors were K-ras-negative showed the greatest difference in median survival with radiation therapy (median survival 30.8 mo vs 7.8 mo with no radiation, p = 0.005).


Asunto(s)
Adenocarcinoma/genética , Genes p53 , Genes ras , Mutación , Neoplasias Pancreáticas/genética , Adenocarcinoma/mortalidad , Adenocarcinoma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Secuencia de Bases , Cartilla de ADN/genética , Femenino , Expresión Génica , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/terapia , Pronóstico , Tasa de Supervivencia , Proteína p53 Supresora de Tumor/metabolismo
9.
Pancreas ; 14(3): 229-36, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9094152

RESUMEN

HER-2/neu expression in pancreatic adenocarcinoma has been inconsistently reported and has not been fully evaluated with respect to histologic grade and tumor grade heterogeneity. We studied HER-2/neu expression in a series of 79 primary pancreatic carcinomas using immunohistochemical methods, with expression scored for each histologic grade represented in each tumor. We found significantly lower expression of HER-2/neu in poorly differentiated (PD) portions of tumors-those areas lacking glandular differentiation-compared to well-differentiated (WD) and moderately differentiated (MD) portions of tumors. Forty-two of 68 (62%) invasive tumors with WD or MD glands showed moderate or strong expression of HER-2/neu in WD/MD areas; only 6 of 32 (19%) invasive tumors with PD areas showed similar expression in PD. In mutually exclusive patient sets, we also found a statistically different prevalence of HER-2/neu expression in patients with PD (6/32 cases; 19%) and without PD (29/47 cases; 62%) tumors (p < 0.001). Twenty-three cases had directly comparable areas of PD versus MD or WD. In 19 of 23 cases HER-2/neu expression was graded comparatively lower (or negative) in areas of PD than in MD or WD. Overall 46 of 79 cases (58%) showed moderate to strong HER-2/neu expression inclusive of all histologic grades, and 63 of 79 (80%) cases were HER-2/neu positive, if including weak or focal staining. There was no significant difference in the survival of patients with HER-2/neu-positive versus-negative tumors or in patients with versus without PD tumors. We have confirmed that although HER-2/neu gene expression is common to many pancreatic carcinomas, it is not common to tumors lacking glandular differentiation. HER-2/neu gene expression could not be related to survival differences--perhaps due to overall poor survival within adenocarcinomas of the pancreas--but the pattern of HER-2/neu expression suggests a relationship to glandular differentiation and early oncogenesis.


Asunto(s)
Adenocarcinoma/genética , Genes erbB-2 , Neoplasias Pancreáticas/genética , Adenocarcinoma/mortalidad , Adenocarcinoma/patología , Expresión Génica , Humanos , Invasividad Neoplásica , Neoplasias Pancreáticas/mortalidad , Neoplasias Pancreáticas/patología , Pronóstico , Análisis de Supervivencia
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