RESUMO
PURPOSE: The Southwest Oncology Group (SWOG) coordinated an Intergroup study with the participation of Radiation Therapy Oncology Group (RTOG), and Eastern Cooperative Oncology Group (ECOG). This randomized phase III trial compared chemoradiotherapy versus radiotherapy alone in patients with nasopharyngeal cancers. MATERIALS AND METHODS: Radiotherapy was administered in both arms: 1.8- to 2.0-Gy/d fractions Monday to Friday for 35 to 39 fractions for a total dose of 70 Gy. The investigational arm received chemotherapy with cisplatin 100 mg/m2 on days 1, 22, and 43 during radiotherapy; postradiotherapy, chemotherapy with cisplatin 80 mg/m2 on day 1 and fluorouracil 1,000 mg/m2/d on days 1 to 4 was administered every 4 weeks for three courses. Patients were stratified by tumor stage, nodal stage, performance status, and histology. RESULTS: Of 193 patients registered, 147 (69 radiotherapy and 78 chemoradiotherapy) were eligible for primary analysis for survival and toxicity. The median progression-free survival (PFS) time was 15 months for eligible patients on the radiotherapy arm and was not reached for the chemo-radiotherapy group. The 3-year PFS rate was 24% versus 69%, respectively (P < .001). The median survival time was 34 months for the radiotherapy group and not reached for the chemo-radiotherapy group, and the 3-year survival rate was 47% versus 78%, respectively (P = .005). One hundred eighty-five patients were included in a secondary analysis for survival. The 3-year survival rate for patients randomized to radiotherapy was 46%, and for the chemoradiotherapy group was 76% (P < .001). CONCLUSION: We conclude that chemoradiotherapy is superior to radiotherapy alone for patients with advanced nasopharyngeal cancers with respect to PFS and overall survival.
RESUMO
OBJECTIVE: Cellular DNA characteristics derived from pretreatment biopsy (PTB) may become important for predicting treatment outcomes in patients with head and neck squamous cell cancer (HNSCC). Whether the PTB adequately represents the whole specimen is of critical importance. STUDY DESIGN: In a series of >700 HNSCCs, we identified 59 cases in which the PTB and the surgical resection (SR) met the following criteria: PTB and SR were from the same site, and SR was obtained within 5 weeks of PTB with no intervening treatments. RESULTS: Twenty-nine percent of the PTB specimens were DNA diploid. Only 1 of the 11 subsequent DNA diploid SR was associated with a DNA aneuploid PTB (91% concordance). Of the 48 DNA aneuploid tumors, 3 were associated with DNA diploid PTB (94% concordance). Three other DNA aneuploid SRs were associated with PTB of poor quality. CONCLUSION: With respect to DNA ploidy, PTB are representative of SR specimens.
Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , DNA/análise , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Aneuploidia , Biópsia , Carcinoma de Células Escamosas/cirurgia , Técnicas de Cultura , Diploide , Citometria de Fluxo , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Estadiamento de NeoplasiasRESUMO
PURPOSE: We sought to identify autoantigens recognized by antibodies in breast cancer patient sera with potential diagnostic or prognostic significance. EXPERIMENTAL DESIGN: Serum from a female breast cancer patient exhibiting a high titer antinuclear antibody was used to screen a HeLa cDNA expression library, leading to the cloning of a cDNA for the M(r) 32,000 subunit of replication protein A (RPA32). RPA32 expression and localization were assayed in autologous tumor by monoclonal antibody staining. A specific ELISA using recombinant protein was used to screen sera from 801 breast cancer patients and 65 controls. RESULTS: A relationship between anti-replication protein A (RPA) antibodies and the ductal breast carcinoma of the proband was suggested by overexpression and aberrant localization of RPA32 in tumor cells as compared with surrounding normal ductal tissue and by the presence of anti-RPA32 antibodies before the diagnosis. The prevalence of anti-RPA32 antibodies was significantly higher (P < 0.01) among breast cancer patients (87 of 801 patients) than among noncancer controls (0 of 65 controls). Similarly, anti-RPA32 antibodies were present in 4 of 39 patients with intraductal in situ carcinoma. No associations were found between anti-RPA antibodies and survival, occurrence of a second tumor, metastases, or antibodies to p53. Reactivity to RPA32 also was detected in sera from 3 of 47 patients with other cancers. CONCLUSIONS: In view of the central role of RPA in DNA replication, recombination, and repair, we suggest that autoimmunity to RPA32 may reflect molecular changes involved in the process of tumorigenesis. The finding of antibodies to RPA32 before diagnosis and their prevalence in in situ carcinoma suggest that they are potentially useful markers of early disease.
Assuntos
Autoanticorpos/sangue , Autoantígenos/imunologia , Biomarcadores Tumorais/sangue , Neoplasias da Mama/sangue , Neoplasias da Mama/imunologia , Carcinoma Ductal de Mama/imunologia , Proteínas de Ligação a DNA/imunologia , Antígenos de Neoplasias/imunologia , Autoimunidade , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma in Situ/sangue , Carcinoma in Situ/imunologia , Carcinoma in Situ/patologia , Carcinoma Ductal de Mama/sangue , Carcinoma Ductal de Mama/patologia , Carcinoma de Células Escamosas/sangue , Carcinoma de Células Escamosas/imunologia , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , Clonagem Molecular , Ensaio de Imunoadsorção Enzimática , Feminino , Biblioteca Gênica , Células HeLa , Neoplasias de Cabeça e Pescoço/sangue , Neoplasias de Cabeça e Pescoço/imunologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Técnicas Imunoenzimáticas , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Peso Molecular , Núcleo Familiar , Valores de Referência , Proteína de Replicação A , Proteína Supressora de Tumor p53/imunologiaRESUMO
A phase II trial of gemcitabine (Gemzar), a nucleoside analogue with broad activity in solid tumors, was performed in patients with recurrent or metastatic squamous cell carcinoma of the head and neck. A total of 26 eligible patients were registered to receive a dose of 1250 mg/m2 weekly for 3 weeks, followed by a 1 week rest. Toxicity was evaluable in 26 patients. Nausea and vomiting occured in 11 and 6 patients, repectively. Grade 3 or 4 hematologic toxicities were infrequent. Two patients developed neutropenic infections. One patient developed fatal liver failure which was thought due to progressive liver metastases or infection 14 days after a single dose of gemcitabine. There were no objective treatment responses (95% CI 0-13%), with a median survival of 6 months in this highly resistant disease population. Gemcitabine is not considered active enough as monotherapy for further evaluation in this disease population.
Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Antimetabólitos Antineoplásicos/efeitos adversos , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/secundário , Desoxicitidina/efeitos adversos , Avaliação de Medicamentos , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/tratamento farmacológico , Ribonucleotídeo Redutases/antagonistas & inibidores , Taxa de Sobrevida , GencitabinaRESUMO
PURPOSE: We conducted a Phase 1 study to determine the maximal tolerated dose and maximum biologically active dose of the E1A gene delivered by intratumoral injection as a lipid complex with 3 beta[N-(n',n'-dimethylaminoethane)-carbamoyl] cholesterol/dioleoylphosphatidyl-ethanolamine (tgDCC-E1A). The E1A adenovirus gene functions as a tumor inhibitor gene by repressing oncogene transcription; modulating gene expression, resulting in cellular differentiation; and inducing apoptosis of cancer cells. E1A also sensitizes cancer cells to chemotherapeutic drugs such as etoposide, cisplatin, and taxol. EXPERIMENTAL DESIGN: Nine patients with recurrent and unresectable breast cancer and nine patients with head and neck cancer were enrolled. One tumor nodule in each patient was injected with tgDCC-E1A. Safety, tumor response, E1A gene transfer, and down-regulation of HER-2/neu were evaluated. RESULTS: No dose-limiting toxicity was observed in the four dose groups (15, 30, 60, and 120 microg DNA/cm of tumor). All patients tolerated the injections, although several experienced pain and bleeding at the injection site. A maximally tolerated dose was not reached in this study. E1A gene transfer was demonstrated in 14 of 15 tumor samples tested, and down-regulation of HER-2/neu was demonstrated in two of the five patients who overexpressed HER-2/neu at baseline. HER-2/neu could not be assessed in other posttreatment tumor samples because of extensive necrosis. In one breast cancer patient, no pathological evidence of tumor was found on biopsy of the treated tumor site at week 12. In 16 patients evaluable for tumor response, 2 had minor responses, 8 had stable disease, and 6 had progressive disease. CONCLUSIONS: Gene therapy with an E1A gene:lipid complex appears to be safe and warrants further testing.
Assuntos
Proteínas E1A de Adenovirus/uso terapêutico , Neoplasias da Mama/terapia , Terapia Genética , Neoplasias de Cabeça e Pescoço/terapia , Proteínas E1A de Adenovirus/efeitos adversos , Proteínas E1A de Adenovirus/genética , Idoso , Neoplasias da Mama/genética , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Feminino , Técnicas de Transferência de Genes , Neoplasias de Cabeça e Pescoço/genética , Humanos , Lipossomos , Masculino , Pessoa de Meia-Idade , Receptor ErbB-2/metabolismo , Recidiva , Transfecção , Resultado do TratamentoRESUMO
The Head and Neck Cancer Intergroup phase III clinical trial (Int 0099) for patients with locally advanced, squamous cell carcinomas (SCC) of the nasopharynx (or NPC) has been recently completed in the United States. The results of this study have defined the new standard of treatment for the group of patients studied. Patients with untreated, locally advanced stages III and IV NPC were randomized to a conventional course of radiation, or to radiation given concurrently with chemotherapy followed by three courses of combination chemotherapy. The 3-year progression-free survival (PFS) and overall survival (OS) were 24% versus 69% (P < 0.001) and 46% versus 76% (P < 0.001) for the control and experimental groups, respectively. Recent updates of these survival figures show that they have not changed appreciably. The considerable improvement in OS versus PFS for the patient group receiving radiation alone is accounted for primarily by re-treatment with concurrent radiation-chemotherapy, combination chemotherapy, and isolated salvage neck dissections. Highly significant differences in local control (41% vs 14%) and distant metastases (35% vs 13%) were demonstrated in favor of the chemoradiation treatment arm. The median age for these patients was 51 years, with a 2:1 male to female ratio. Although many patients had a significant history of tobacco exposure with or without alcohol use or abuse, only 24% had keratinizing or well-differentiated squamous (World Health Organization I) type tumors. Whether these results can be extrapolated to the more common Asian variety (WHO II and III) of advanced NPC must be addressed in future clinical trials.
Assuntos
Carcinoma de Células Escamosas/terapia , Neoplasias Nasofaríngeas/terapia , Adulto , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/fisiopatologia , Terapia Combinada , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/fisiopatologia , Invasividade Neoplásica , Estadiamento de Neoplasias , Análise de SobrevidaRESUMO
We have examined the ability of gamma-irradiation and bleomycin to induce apoptosis in a model system consisting of cell lines derived from naturally occurring human head-and-neck squamous-cell carcinomas with contrasting p53 status and expression levels of pro- and anti-apoptotic molecules. Following exposure to gamma-irradiation (20 Gy) or bleomycin (3.5 microM) for 0 to 96 hr, cells expressing either transcriptionally inactive mutant p53 (HN6) or a truncated p53 molecule (HN19) underwent apoptosis, as assessed by fluorescence-activated cell sorting and terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling, in contrast to cells that express wild-type p53 (HN30), suggesting that apoptosis induced by these agents occurs by p53-independent mechanisms. Apoptosis in HN6 and HN19 cells was preceded by a G(2)/M cell-cycle block, as analyzed by DNA content and BrdU staining. In contrast, HN30 cells remained blocked in both G(1) and G(2)/M and failed to re-enter the cell cycle. Levels of Bcl-2 were elevated in 3 of 10 cell lines, and only marginal differences were observed for Bcl-x(L). Pro-apoptotic proteins bax and Bcl-x(S) were detectable in normal keratinocytes and 4 tumor cell lines. Bax-delta (16 kDa) was highly represented in normal keratinocytes, and levels of bak were variable between cell lines. Elevated expression of Bcl-2 failed to protect HN19 cells from either gamma-irradiation or bleomycin-induced apoptosis. Our data support the existence of p53- and Bcl-2-independent pathways regulating apoptosis in keratinocytes and suggest that efficacy of either radiotherapy or bleomycin treatment for oral squamous-cell neoplasms may not, therefore, be influenced solely by endogenous p53 status.
Assuntos
Antibióticos Antineoplásicos/farmacologia , Apoptose , Bleomicina/farmacologia , Carcinoma de Células Escamosas/terapia , Raios gama , Neoplasias de Cabeça e Pescoço/terapia , Proteína Supressora de Tumor p53/fisiologia , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Células Tumorais CultivadasRESUMO
Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer among men in the developed world affecting the oral cavity, salivary glands, larynx and pharynx. Utilizing tissue from patients with HNSCC, we sought to systematically identify and catalog genes expressed in HNSCC progression. Here, we demonstrate the successful use of laser capture microdissection for procuring pure populations of cells from patient tissue sets comprised of oral squamous cell carcinomas (OSCCs) and matching normal tissue. From the estimated 5000 cells procured for each sample, we were able to extract total RNA (14.7-18.6 ng) of sufficient quality to transcribe GAPDH by reverse transcriptase-polymerase chain reaction (RT-PCR). The RNA was used for the synthesis of blunt-ended, double-strand complementary DNAs (cDNAs) by oligo (dT)-mediated reverse transcription, followed by addition of linkers. Primers specific for these linkers with uracil deglycosylase-compatible ends were used to amplify these cDNAs by PCR and the product was subcloned into the pAMP10 cloning vector. Ninety-six clones from each of six libraries were randomly sequenced and results indicated that 76-96% of the inserts represent either anonymous expressed sequence tags (ESTs) (25-48%), known genes (9-29%) or novel sequences (27-51%), respectively, with very little redundancy. These results demonstrate that high quality, representative cDNA libraries can be generated from microdissected OSCC tissue. Furthermore, these finding suggest the existence of at least 132 novel genes expressed in our cDNA libraries, which may have a role in the pathogenesis of HNSCC, and may represent novel markers for early detection as well as targets for pharmacological intervention in this disease.
Assuntos
Carcinoma de Células Escamosas/genética , DNA Complementar/genética , Dissecação/métodos , Perfilação da Expressão Gênica/métodos , Biblioteca Gênica , Lasers , Neoplasias Bucais/genética , Idoso , Biópsia/métodos , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , Dissecação/instrumentação , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/patologia , Neoplasias Bucais/patologia , RNA Neoplásico/genética , RNA Neoplásico/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
Although risk factors for squamous cell carcinomas of the head and neck (HNSCC) are well recognized, very little is known about the molecular mechanisms responsible for this malignancy. Furthermore, the ability to investigate gene expression profiles at different stages of tumor progression is usually limited by the remarkable heterogeneity of these neoplastic lesions. Here, we show the successful use of laser capture microdissection (LCM) to procure specific cell populations. The 5000 cells from representative sets of HNSCC and their matching normal tissues are sufficient to extract RNA of high integrity for the synthesis of labeled amplified cDNA probes which can then be hybridized to these membranes arrayed with known human cancer-related cDNAs. Furthermore, when compared to normal tissues, we demonstrate a consistent decrease in expression of differentiation markers such as cytokeratins, and an increase in the expression of a number of signal transducing and cell cycle regulatory molecules, as well as growth and angiogenic factors and tissue degrading proteases. Unexpectedly, we also found that most HNSCC overexpress members of the wnt and notch growth and differentiation regulatory system, thus suggesting that the wnt and notch pathways may contribute in squamous cell carcinogenesis. This experimental approach may facilitate the identification candidate markers for the early detection of preneoplastic lesions, as well as novel targets for pharmacological intervention in this disease.
Assuntos
Carcinoma de Células Escamosas/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias de Cabeça e Pescoço/genética , Diferenciação Celular , Divisão Celular , Células Epiteliais/citologia , Humanos , Lasers , Microscopia Confocal/métodos , Hibridização de Ácido Nucleico/métodos , Análise de Sequência com Séries de Oligonucleotídeos/métodos , RNA Neoplásico/isolamento & purificaçãoRESUMO
The Cancer Genome Anatomy Project (CGAP) is a large cooperative effort sponsored by the US National Institutes of Health designed to find, catalog and annotate genes that are expressed during cancer development. In the past 2 years, the CGAP has sequenced over 700,000 clones from approximately 140 cDNA libraries, resulting in the identification of over 30,000 new human genes. As a first step in applying this project to oral cancer we entered four cell lines--two from oral cancer, one from primary oral keratinocytes, and one from oral keratinocytes which had been immortalized by human papillomavirus. Libraries of cDNA were made and sequenced and the data were deposited in GenBank. The expressed genes were then identified where possible. The cell lines, and the total number of expressed genes that were cloned from each were: HN3 (oral cancer), 263 genes; HN4 (oral cancer), 550 genes; HN5 (primary keratinocytes), 237 genes; HN6 (immortalized keratinocytes), 408 genes. The total number of different genes that were found was 1160. A total of 38 new genes, of unknown function, were discovered. The data presented here represent a beginning of the application of the CGAP technology to oral cancer. Even though the data are still quite incomplete, they already represent a large quantity of new information and clones of potential utility to the oral cancer community, and provide a glimpse of the data sets to be forthcoming from the Project. It must therefore be expected that there will soon be a large expansion in the volume of data regarding the genetics of oral cancer. Those who study this disease must be prepared to develop new methods of analysis and storage for handling the oncoming volumes of information.
Assuntos
Neoplasias Bucais/genética , Células Clonais , Expressão Gênica , Biblioteca Genômica , Humanos , Queratinócitos , Sensibilidade e EspecificidadeRESUMO
Epidemiological studies have shown lower incidence of breast and prostate cancers in Asian populations consuming a traditional diet rich in soy. Protection from these cancers was attributed to the isoflavones, particularly genistein and daidzein found in vivo as the major metabolites of soy isoflavones. However, the role of isoflavones in head and neck cancer is less clear. In our previous studies we reported that genistein can induce cell growth inhibition by arresting the cells at S/G2-M phases, and also induces apoptosis in HN4 squamous cell carcinoma of the head and neck cell line (HNSCC). In this report we show that these changes are accompanied by the down-regulation of Cdk1, and CyclinB1, and up-regulation of the cyclin dependent kinase (Cdk) inhibitor p21WAF1, which may be responsible for the induction of cell cycle arrest and apoptosis. The evidence for the induction of apoptosis was supported by the appearance of DNA ladder as reported previously, and further supported by our current results on the cleavage of poly-ADP-ribose polymerase (PARP), hallmark of apoptosis. This was also accompanied by the up-regulation of Bax, with modest down-regulation of Bcl-2 protein expression, which changes the balance between pro- and anti-apoptosis molecules in favor of pro-apoptosis. Furthermore, we also observed down-regulation and degradation of Cdc25C, which is a marker of cell proliferation, and plays important role in CyclinB-Cdk1 complex activation. The down-regulation followed by the degradation of Cdc25C is an indicator of G2/M arrest and anti-proliferation effects of genistein. Collectively, these data provide strong molecular evidence for the anti-tumor activity of genistein in HNSCC cells.
Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/metabolismo , Proteínas de Ciclo Celular/efeitos dos fármacos , Genisteína/farmacologia , Neoplasias de Cabeça e Pescoço/metabolismo , Apoptose/fisiologia , Proteína Quinase CDC2/efeitos dos fármacos , Proteína Quinase CDC2/metabolismo , Proteínas de Ciclo Celular/metabolismo , Ciclina B/efeitos dos fármacos , Ciclina B/metabolismo , Ciclina B1 , Inibidor de Quinase Dependente de Ciclina p21 , Ciclinas/efeitos dos fármacos , Ciclinas/metabolismo , Humanos , Proteínas Proto-Oncogênicas/efeitos dos fármacos , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Células Tumorais Cultivadas/efeitos dos fármacos , Regulação para Cima , Proteína X Associada a bcl-2RESUMO
BACKGROUND: Appropriate adjuvant chemotherapy for resected head and neck cancer patients has yet to be defined. Multiple trials have noted trends toward improved disease-free survival and local control. The Southwest Oncology Group undertook a feasibility trial of postoperative cisplatin and radiotherapy followed by three cycles of cisplatin and 5-fluorouracil. METHODS: Patients with resected stage III or IV head and neck cancer received cisplatin, 100 mg/m2, on days 1, 22, and 43 of radiotherapy. This therapy was followed by three cycles of cisplatin, 100 mg/m2 or last tolerated dose, and 5-fluorouracil, 1000 mg/m2, on days 1 to 4 every 21 days. RESULTS: Seventy-two patients from 22 institutions were registered; 68 were evaluable. Sixty-eight patients received radiotherapy. Only 25 of 68 patients (36.7%) were able to complete all six cycles of chemotherapy. Forty-three of 68 patients (63%) completed all three cycles with radiotherapy. Toxicities were tolerable. One toxic death occurred. CONCLUSIONS: It is not feasible to deliver six cycles of chemotherapy postoperatively in the sequence described. Compliance issues need further exploration to define effective adjuvant chemotherapy for head and neck patients.
Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Fluoruracila/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/cirurgia , Adulto , Idoso , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/efeitos adversos , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Cisplatino/administração & dosagem , Cisplatino/efeitos adversos , Terapia Combinada , Intervalo Livre de Doença , Estudos de Viabilidade , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de TempoRESUMO
OBJECTIVE/HYPOTHESIS: We examined whether p53 gene mutations were predictive of clinical behavior in laryngeal cancer. STUDY DESIGN: Retrospective study of 45 patients with laryngeal cancer from 1985 to 1997. METHODS: DNA was extracted from tumor tissue and subject to polymerase chain reaction single-strand conformational polymorphism (PCR-SSCP) as well as DNA sequencing. The clinical outcome was correlated to the presence or absence of a p53 mutation. RESULTS: The p53 gene was analyzed by direct DNA sequencing and was found to be mutated in 33% (15/45) of patients. The presence of a p53 mutation was associated with a significant improvement in overall survival (80% vs. 43%, P < .03) and a trend toward improved disease-free survival (87% vs. 60%, P = .08). When other prognostic factors were adjusted, multivariate analysis revealed a trend toward improvement in overall survival as well as disease-free survival. CONCLUSION: Depending on the location of a p53 mutation, the suppressive functions or clinical outcome may or may not be affected. Fifty-three percent of mutations were detected in nonconserved regions as opposed to 17% as reported in colon cancer. In colon cancer, mutations in conserved regions of the p53 gene predicted a poorer survival, whereas nonconserved gene mutations were not predictive. In our group of patients. p53 mutations predicted a better prognosis, which may be due to a large proportion of mutations that lie within nonconserved areas. The predictive power of p53 gene mutations may depend on functional loss and inactivation of highly conserved areas and must be tested in a prospective trial.
Assuntos
Análise Mutacional de DNA , Neoplasias Laríngeas/genética , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Sequência de Aminoácidos/genética , Sequência Conservada/genética , Feminino , Humanos , Neoplasias Laríngeas/mortalidade , Neoplasias Laríngeas/patologia , Laringectomia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Repetições de Trinucleotídeos/genéticaRESUMO
Flavopiridol (HMR 1275) has been identified recently as a novel antineoplastic agent in the primary screen conducted by the Developmental Therapeutics Program, National Cancer Institute. Flavopiridol inhibits most cyclin-dependent kinases (cdks) and displays unique anticancer properties. Here, we investigated whether this compound was effective against head and neck squamous cell carcinomas (HNSCC). Exposure of HNSCC cells to flavopiridol diminished cdc2 and cdk2 activity and potently inhibited cell proliferation (IC50 43-83 nM), which was concomitant with the appearance of cells with a sub-G1 DNA content. Moreover, DNA fragmentation and TUNEL (terminal deoxynucleotidyl transferase-mediated nick end labeling) reaction confirmed that flavopiridol induces apoptosis in all cell lines, even on certain HNSCC cells that are insensitive to apoptosis to DNA-damaging agents (gamma-irradiation and bleomycin). A tumorigenic HNSCC cell line was used to assess the effect of flavopiridol in vivo. Treatment (5 mg/kg per day, intraperitoneally) for 5 d led to the appearance of apoptotic cells in the tumor xenografts and caused a 60-70% reduction in tumor size, which was sustained over a period of 10 wk. Flavopiridol treatment also resulted in a remarkable reduction of cyclin D1 expression in HNSCC cells and tumor xenografts. Our data indicate that flavopiridol exerts antitumor activity in HNSCC, and thus it can be considered a suitable candidate drug for testing in the treatment of refractory carcinomas of the head and neck.
Assuntos
Antineoplásicos/farmacologia , Apoptose , Quinases relacionadas a CDC2 e CDC28 , Carcinoma de Células Escamosas/tratamento farmacológico , Quinases Ciclina-Dependentes/antagonistas & inibidores , Flavonoides/farmacologia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Piperidinas/farmacologia , Animais , Proteína Quinase CDC2/metabolismo , Ciclo Celular/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Ciclina D1/biossíntese , Ciclina D1/genética , Ciclina D3 , Ciclina E/genética , Quinase 2 Dependente de Ciclina , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/genética , Inibidores Enzimáticos/farmacologia , Feminino , Expressão Gênica , Inibidores do Crescimento/farmacologia , Camundongos , Camundongos Nus , Proteínas Serina-Treonina Quinases/metabolismo , Transplante Heterólogo , Células Tumorais CultivadasRESUMO
The excessive proliferation exhibited by cancer cells is frequently a result of their failure to adequately regulate cell cycle progression. In the present study, we developed a xenograft model of oral cancer in athymic mice, using squamous carcinoma cell lines and examined the ability of the cyclin-dependent kinase inhibitor p21 (WAF1/Cip1) to retard tumour growth in vivo, using a retroviral delivery system. Human p21 cDNA was cloned by polymerase chain reaction, expressed, and the encoded protein shown to have biological activity in in vitro kinase assays. Amphotropic retrovirus cultures which expressed recombinant p21 were generated and used to treat established squamous cell carcinoma xenografts. Two weeks following onset of treatment tumours injected with p21 virus producer cells showed a reduction in size between 3- and 10-fold compared with tumours which received control cells which produced control virus alone. The data indicate that recombinant p21 may be of future use for therapeutic intervention in oral cancer.
Assuntos
Carcinoma de Células Escamosas/terapia , Ciclinas/fisiologia , Terapia Genética/métodos , Neoplasias Bucais/terapia , Animais , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Inibidor de Quinase Dependente de Ciclina p21 , Vetores Genéticos , Humanos , Camundongos , Camundongos Nus , Neoplasias Bucais/metabolismo , Neoplasias Bucais/patologia , Transplante de Neoplasias , Retroviridae/genética , Transplante Heterólogo , Células Tumorais CultivadasRESUMO
Cell lines developed from head and neck squamous cell carcinomas exhibit variable responses to the negative regulatory effects of transforming growth factor beta (TGF beta) on cell growth. To analyse the effects of TGF beta on regulators of cell cycle progression, we characterised cell lines derived from head and neck squamous cell carcinoma (HNSCC) for their biological sensitivities to TGF beta, growth inhibition, then examined the effects of TGF beta treatment on the expression and activity of cyclin dependent kinases (CDKs) and inhibitors of these kinases. Western blot analysis of cell lysates from untreated or TGF beta-treated cultures showed no alterations in expression of CDK2, CDK4, CDK6 or cyclin E in cell lines which were either sensitive (HaCaT, HN6) or refractory (HN12, HN30) to the growth-inhibitory effects of TGF beta. However, treatment of cells with TGF beta resulted in a several fold increase in cellular levels of p21 (WAF1/Cip1), irrespective of biological response. Immune complex in vitro kinase assays demonstrated that the activity of CDK2 was inhibited by exposure to ligand in each case, confirming that a TGF beta signalling pathway which regulates kinase activity was intact in these cell lines. The data suggest that cellular factors expressed in HN12 and HN30 enable these cells to override TGF beta-mediated inhibition of CDK2 activity and allow cell cycle progression. This may represent an important mechanism which allows cells to evade growth arrest during malignant progression.
Assuntos
Quinases relacionadas a CDC2 e CDC28 , Carcinoma de Células Escamosas/enzimologia , Quinases Ciclina-Dependentes/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/enzimologia , Proteínas Serina-Treonina Quinases/efeitos dos fármacos , Fator de Crescimento Transformador beta/farmacologia , Carcinoma de Células Escamosas/patologia , Divisão Celular , Ciclina E/metabolismo , Quinase 2 Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p21 , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/metabolismo , Inibidores Enzimáticos/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Proteínas Serina-Treonina Quinases/metabolismo , Células Tumorais CultivadasRESUMO
PURPOSE: The Southwest Oncology Group (SWOG) coordinated an Intergroup study with the participation of Radiation Therapy Oncology Group (RTOG), and Eastern Cooperative Oncology Group (ECOG). This randomized phase III trial compared chemoradiotherapy versus radiotherapy alone in patients with nasopharyngeal cancers. MATERIALS AND METHODS: Radiotherapy was administered in both arms: 1.8- to 2.0-Gy/d fractions Monday to Friday for 35 to 39 fractions for a total dose of 70 Gy. The investigational arm received chemotherapy with cisplatin 100 mg/m2 on days 1, 22, and 43 during radiotherapy; postradiotherapy, chemotherapy with cisplatin 80 mg/m2 on day 1 and fluorouracil 1,000 mg/m2/d on days 1 to 4 was administered every 4 weeks for three courses. Patients were stratified by tumor stage, nodal stage, performance status, and histology. RESULTS: Of 193 patients registered, 147 (69 radiotherapy and 78 chemoradiotherapy) were eligible for primary analysis for survival and toxicity. The median progression-free survival (PFS) time was 15 months for eligible patients on the radiotherapy arm and was not reached for the chemo-radiotherapy group. The 3-year PFS rate was 24% versus 69%, respectively (P < .001). The median survival time was 34 months for the radiotherapy group and not reached for the chemo-radiotherapy group, and the 3-year survival rate was 47% versus 78%, respectively (P = .005). One hundred eighty-five patients were included in a secondary analysis for survival. The 3-year survival rate for patients randomized to radiotherapy was 46%, and for the chemoradiotherapy group was 76% (P < .001). CONCLUSION: We conclude that chemoradiotherapy is superior to radiotherapy alone for patients with advanced nasopharyngeal cancers with respect to PFS and overall survival.
Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Cisplatino/administração & dosagem , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/radioterapia , Radiossensibilizantes/administração & dosagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Escamosas/mortalidade , Cisplatino/efeitos adversos , Terapia Combinada , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/mortalidade , Recidiva Local de Neoplasia , Radiossensibilizantes/efeitos adversos , Análise de SobrevidaRESUMO
A phase II trial of Tomudex (raltitrexed, ZD 1694), a new thymidylate synthase inhibitor, was performed in patients with recurrent or metastatic squamous cell carcinoma of the head and neck. This trial demonstrated that Tomudex was well tolerated in this patient population. Nausea and vomiting were minimal, and hematologic toxicities were relatively infrequent. Only one patient was withdrawn from the study due to toxicity (grade 4 diarrhea). One patient exsanguinated from a rent in the carotid artery in an area of tumor involvement, and was categorized as a grade 5 toxicity. Thus 25/27 patients were able to complete at least 2 cycles of treatment. Tomudex demonstrated a 3.7% response rate (95% CI 0.1-19%), with a median survival of 6 months in this highly resistant disease population. Tomudex is not considered active enough as monotherapy for further evaluation in this disease population.
Assuntos
Antimetabólitos Antineoplásicos/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Quinazolinas/uso terapêutico , Tiofenos/uso terapêutico , Idoso , Carcinoma de Células Escamosas/secundário , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Análise de SobrevidaRESUMO
Progressive deregulation of the cell-division cycle is thought to contribute to the establishment and progression of neoplasia. Previously, we have documented the in vivo inactivation of p16INK4A, an inhibitor of G1 cyclin-dependent kinases, in squamous cell carcinomas of the head and neck region. In the present study, we extend these findings by examining the expression and functional activity of cyclin-dependent kinases (CDKs) and their regulatory subunits using a model system of cell lines derived from squamous cell carcinomas. Increased activity of CDK4 and 6 was universal in tumor cells compared with normal keratinocytes, reflecting over-expression of either or both kinases. In contrast to other studies, over-expression of cyclin D1, a regulatory subunit of CDK4 and 6, was not observed. Increased activity of CDK2 was less frequent and was related to over-expression of cyclin A and/or E. All tumor cell lines showed increased expression of proliferating cell nuclear antigen compared to normal keratinocytes. Four SCC cell lines, including one tumor-metastasis pair derived from a single patient, failed to express the p15INK4B transcript. Western blot analysis of cell lysates revealed normal or reduced levels of p27KIP1 in tumor cells compared to normal keratinocytes. However, failure to express wild-type p53 was not reflected by lower levels of p21WAF1. Our data suggest that cell-cycle deregulation is likely to occur by multiple mechanisms during the genesis of head and neck squamous cell carcinomas. Furthermore, p16INK4A is likely to be the primary target for inactivation on chromosome 9p21 in these tumors as p15INK4B loss occurs less frequently.
Assuntos
Carcinoma de Células Escamosas/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Ciclinas/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Proteínas de Neoplasias/metabolismo , Ciclina G , Ciclina G1 , Quinases Ciclina-Dependentes/antagonistas & inibidores , Humanos , Antígeno Nuclear de Célula em Proliferação/metabolismo , Células Tumorais CultivadasRESUMO
Loss of wild-type p53, either through deletion or mutation, has been demonstrated in most squamous cell carcinomas of the head and neck (HNSCC). Whether these mutant molecules contribute to tumor progression purely through loss of wild-type functions or by growth-promoting mechanisms, however, remains unclear. To begin to address these issues, we isolated a series of p53 cDNAs from HNSCC cell lines that contain missense or nonsense point mutations, insertions, or deletions. The ability of each of these molecules to transform NIH/3T3 cells to a malignant phenotype was assessed by stable transfection and expression under the control of a strong heterologous promoter. NIH/3T3 cells transfected with pLTR6p53, which harbors an H179L missense mutation, formed large tumors rapidly (in less than 4 wk) when transplanted to athymic mice, as did cells expressing pLTR13p53, which had undergone a V173F missense mutation and an in-frame deletion of 48 bp between codons 208 and 223. Cells transfected with pLTR17p53, predicted from the nucleotide sequence to encode a severely truncated p53 corresponding to the N-terminal 56 amino acids, also formed tumors. Cells transfected with pLTR15p53, which was predicted to encode a less severely truncated molecule, formed much smaller tumors and at lower frequencies. NIH/3T3 cells transfected with pLTR12p53 (exon 7 splice donor mutant), pLTRwtp53 (wild-type p53), or vector alone failed to form tumors for up to 2 mo after transplantation. pLTR6p53-transfected cells exhibited a highly malignant phenotype with invasion of regional lymph nodes, mediastinal and lung metastases, invasion of the abdominal wall, and dissemination throughout the peritoneal cavity. Histological assessment of the tumors revealed intensely vascularized fibrosarcomas with numerous cellular atypia, including frequent and aberrant mitoses. Tumor explants were recultured, and northern blot analysis of cellular RNA confirmed that the expression of exogenous p53 was maintained in each case. These data indicate that different p53 mutants contribute to tumorigenesis by specific mechanisms. Furthermore, the results obtained by using the pLTR17p53 transfectants imply that some truncated molecules may overcome the effects of wild-type p53 to contribute to malignancy.