RESUMO
BACKGROUND: The purpose of this study was to characterise the oncogenic roles of C35, a novel protein binding partner of ΔNp73, in ovarian cancer and to investigate the functional significance of C35-ΔNp73 interaction in the regulation of chemo-resistance. METHODS: C35 expression was evaluated by quantitative real-time PCR in human ovarian cancer tissues and cell lines. The aggressiveness of ovarian cancer cells overexpressing C35 was examined by cell proliferation, migration, soft agar and nude mouse xenograft. The significance of C35-ΔNp73 interaction in chemo-resistance was evaluated by apoptosis assays and cell viability after cisplatin treatment. RESULTS: The expression of C35 was significantly enhanced in human ovarian cancer tissues. Overexpression of C35 augmented proliferation, migration and tumourigenicity in ovarian cancer cell lines. C35 knockdown inhibited cell motility and cell growth. The co-expression of C35 and ΔNp73 by transient or stable transfection in ovarian cancer cells induced greater resistance to cisplatin treatment than did transfection with C35 or ΔNp73 alone. The cisplatin resistance was demonstrated to be caused by increased AKT and NFκB activity induced by C35-ΔNp73. CONCLUSION: Our results suggest that ΔNp73 might cooperate with C35 to promote tumour progression and contribute to cisplatin resistance in ovarian cancer cells. Future studies of the functional roles of ΔNp73 and C35 will provide insight that will aid in the establishment of new strategies and more effective therapies.
Assuntos
Antineoplásicos , Cisplatino , Proteínas de Ligação a DNA/metabolismo , Resistencia a Medicamentos Antineoplásicos/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Proteínas de Neoplasias/metabolismo , Proteínas Nucleares/metabolismo , Neoplasias Ovarianas/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/fisiologia , Feminino , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Camundongos , Camundongos Nus , NF-kappa B/metabolismo , Proteínas de Neoplasias/fisiologia , Proteínas Nucleares/fisiologia , Neoplasias Ovarianas/fisiopatologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Proteína Tumoral p73 , Proteínas Supressoras de Tumor/fisiologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
BACKGROUND: The BRCA1 gene is an important breast-cancer susceptibility gene. Promoter polymorphisms can alter the binding affinity of transcription factors, changing transcriptional activity and may affect susceptibility to disease. METHODS AND RESULTS: Using direct sequencing of the BRCA1 promoter region, we identified four polymorphisms c.-2804T-->C (rs799908:T-->C), c.-2265C-->T (rs11655505:C-->T), c.-2004A-->G (rs799906:A-->G) and c.-1896(ACA)(1)-->(ACA)(2) (rs8176071:(ACA)(1)-->(ACA)(2)) present in Hong Kong Chinese. Each polymorphism was studied independently and in combination by functional assays. Although all four variants significantly altered promoter activity, the c.-2265T allele had stronger binding than the C allele, and the most common mutant haplotype, which contains the c.-2265T allele, increased promoter activity by 70%. Risk association first tested in Hong Kong Chinese women with breast cancer and age-matched controls and replicated in a large population-based study of Shanghai Chinese, together totalling >3000 participants, showed that carriers of the c.-2265T allele had a reduced risk for breast cancer (combined odd ratio (OR) = 0.80, 95% CI 0.69 to 0.93; p = 0.003) which was more evident among women aged >or=45 years at first diagnosis of breast cancer and without a family history of breast cancer (combined OR = 0.75, 95% CI 0.61 to 0.91; p = 0.004). The most common haplotype containing the c.-2265T allele also showed significant risk association for women aged >or=45 years without a family history of breast cancer (OR = 0.64, 95% CI 0.46 to 0.89; p = 0.008). CONCLUSION: This comprehensive study of BRCA1 promoter polymorphisms found four variants that altered promoter activity and with the most significant contribution from c.-2265C-->T, which could affect susceptibility to breast cancer in the Chinese population. Its significance in other populations remains to be investigated.
Assuntos
Proteína BRCA1/genética , Neoplasias da Mama/genética , Polimorfismo Genético/genética , Regiões Promotoras Genéticas/genética , Transcrição Gênica , Povo Asiático/genética , Sítios de Ligação , Neoplasias da Mama/epidemiologia , Estudos de Casos e Controles , China/epidemiologia , Estudos de Coortes , Ensaio de Desvio de Mobilidade Eletroforética , Feminino , Predisposição Genética para Doença , Genótipo , Hong Kong/epidemiologia , Humanos , Fatores de Risco , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
BACKGROUND: Loss of growth inhibitory response to transforming growth factor-beta (TGF-beta) is a common feature of epithelial cancers. Recent studies have reported that genetic lesions and overexpression of oncoproteins in TGF-beta/Smads signalling cascade contribute to the TGF-beta resistance. Here, we showed that the overexpressed FOXG1 was involved in attenuating the anti-proliferative control of TGF-beta/Smads signalling in ovarian cancer. METHODS: FOXG1 and p21(WAF1/CIP1) expressions were evaluated by real-time quantitative reverse-transcription polymerase chain reaction (RT-PCR), western blot and immunohistochemical analyses. The effect of FOXG1 on p21(WAF1/CIP1) transcriptional activity was examined by luciferase reporter assays. Cell lines stably expressing or short hairpin RNA interference-mediated knockdown FOXG1 were established for studying the gain-or-loss functional effects of FOXG1. XTT cell proliferation assay was used to measure cell growth of ovarian cancer cells. RESULTS: Quantitative RT-PCR and western blot analyses showed that FOXG1 was upregulated and inversely associated with the expression levels of p21(WAF1/CIP1) in ovarian cancer. The overexpression of FOXG1 was significantly correlated with high-grade ovarian cancer (P=0.025). Immunohistochemical analysis on ovarian cancer tissue array was further evidenced that FOXG1 was highly expressed and significantly correlated with high-grade ovarian cancer (P=0.048). Functionally, enforced expression of FOXG1 selectively blocked the TGF-beta-induced p21(WAF1/CIP1) expressions and increased cell proliferation in ovarian cancer cells. Conversely, FOXG1 knockdown resulted in a 20-26% decrease in cell proliferation together with 16-33% increase in p21(WAF1/CIP1) expression. Notably, FOXG1 was able to inhibit the p21(WAF1/CIP1) promoter activity in a p53-independent manner by transient reporter assays. CONCLUSION: Our results suggest that FOXG1 acts as an oncoprotein inhibiting TGF-beta-mediated anti-proliferative responses in ovarian cancer cells through suppressing p21(WAF1/CIP1) transcription.
Assuntos
Inibidor de Quinase Dependente de Ciclina p21/antagonistas & inibidores , Fatores de Transcrição Forkhead/fisiologia , Proteínas do Tecido Nervoso/fisiologia , Neoplasias Ovarianas/tratamento farmacológico , Fator de Crescimento Transformador beta/farmacologia , Transporte Ativo do Núcleo Celular , Adulto , Idoso , Linhagem Celular Tumoral , Proliferação de Células , Inibidor de Quinase Dependente de Ciclina p21/genética , Resistencia a Medicamentos Antineoplásicos , Feminino , Fatores de Transcrição Forkhead/análise , Fatores de Transcrição Forkhead/genética , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Proteínas do Tecido Nervoso/análise , Proteínas do Tecido Nervoso/genética , Neoplasias Ovarianas/patologia , Regiões Promotoras Genéticas , Transdução de SinaisRESUMO
OBJECTIVE: To explore Chinese women's perceptions of human papillomavirus (HPV) vaccination and their intention to be vaccinated. DESIGN: A cross-sectional community-based survey study. SETTING: Thirteen community women's health centres of The Family Planning Association of Hong Kong. SAMPLE: A total of 1450 ethnic Chinese women aged 18 or above who attended the health centres. METHODS: Participants completed a written consent and an anonymous questionnaire onsite. MAIN OUTCOME MEASURES: Knowledge and beliefs about HPV and HPV vaccination against cervical cancer and participants' own intention to be vaccinated. RESULTS: About 38% of the participants (n = 527) had heard of HPV and 50% (n = 697) had heard of vaccination against cervical cancer. HPV infection was perceived to be stigmatising and detrimental to intimate, family and social relationships. Despite misconceptions and a grossly inadequate knowledge about HPV and HPV vaccination, 88% of the participants (n = 1219) indicated that they would likely be vaccinated. Majority of the participants believed that sexually experienced women should be vaccinated, while 27% opposed vaccinating sexually naive women. Younger age women who perceived a disruptive impact of HPV infection on intimate relationship and their partners' approval were significantly associated with a positive intention to be HPV vaccinated. CONCLUSIONS: The easy acceptability of HPV vaccination among the mostly sexually experienced Chinese participants and their knowledge deficit on the subject may implicate potential misuse of the vaccines and a false sense of security against cervical cancer. There is a dire need for culturally sensitive and tailored education for the public, women of different ages and their partners about HPV and HPV vaccination. Emphasis must be placed on the prophylactic nature of the current vaccines, the uncertain effects when given to sexually experienced women, the importance of adolescent vaccination and the need for continued cervical screening whether vaccinated or not.
Assuntos
Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus , Satisfação do Paciente/etnologia , Neoplasias do Colo do Útero/virologia , Adolescente , Adulto , Idoso , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Hong Kong/epidemiologia , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/etnologia , Infecções por Papillomavirus/psicologia , Inquéritos e Questionários , Neoplasias do Colo do Útero/etnologia , Adulto JovemAssuntos
Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Carcinoma de Células Escamosas/patologia , Técnicas Citológicas , Detecção Precoce de Câncer , Feminino , Humanos , Imuno-Histoquímica/métodos , Neoplasias do Colo do Útero/patologia , Esfregaço Vaginal/métodosAssuntos
Papillomaviridae/genética , Infecções por Papillomavirus/diagnóstico , Triagem , Displasia do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/diagnóstico , Técnicas Citológicas , Feminino , Humanos , Papillomaviridae/classificação , Infecções por Papillomavirus/virologia , Fragmentos de Peptídeos/genética , Valor Preditivo dos Testes , RNA Viral/análise , Telomerase/genética , Neoplasias do Colo do Útero/virologia , Esfregaço Vaginal , Displasia do Colo do Útero/virologiaAssuntos
Infecções por Papillomavirus/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Adulto , Fatores Etários , Povo Asiático/estatística & dados numéricos , China/epidemiologia , Estudos Transversais , Feminino , Papillomavirus Humano 16/isolamento & purificação , Humanos , Pessoa de Meia-Idade , Papillomaviridae/isolamento & purificação , Infecções por Papillomavirus/prevenção & controle , Infecções por Papillomavirus/virologia , Prevalência , Neoplasias do Colo do Útero/prevenção & controle , Neoplasias do Colo do Útero/virologia , Saúde da MulherRESUMO
Oct4 is a transcription factor that plays a crucial role in maintaining pluripotency of embryonic stem cells. Down-regulation of Oct4 is associated with the differentiation of trophectoderm cell lineage, from which the normal placenta derives. We investigated the methylation and expression status of Oct4 in normal placenta and gestational trophoblastic disease (GTD) as attempts to investigate the role of Oct4 in the pathogenesis of GTD. By methylation-specific PCR, we observed both methylated and unmethylated Oct4 alleles in all 25 first trimester and 10 term placentas while 33% (18/54) of hydatidiform moles, and two choriocarcinoma cell line (JEG3 and JAR), only displayed methylated Oct4 allele. By quantitative TaqMan real-time PCR, Oct4 mRNA was significantly reduced in hydatidiform moles (P=0.04), JEG3 and JAR (P=0.024) when compared with normal placentas. Oct4 methylation was significantly correlated with Oct4 mRNA expression in placenta and GTD (P=0.012). Hypermethylation in minimal promoter and exon 1 region of Oct4 were confirmed in JEG3 and JAR by bisulfite genomic sequencing. The Oct4 mRNA expression in JEG3 and JAR increased after treatment with 5-aza-2'-deoxycytidine and/or trichostatin A. Our findings suggest that Oct4 is down-regulated by hypermethylation in normal placenta and GTD and such process is important in pathogenesis of GTD.
Assuntos
Metilação de DNA , Doença Trofoblástica Gestacional/genética , Fator 3 de Transcrição de Octâmero/genética , Placenta/metabolismo , Azacitidina/análogos & derivados , Azacitidina/farmacologia , Linhagem Celular Tumoral , Metilases de Modificação do DNA/antagonistas & inibidores , Decitabina , Inibidores Enzimáticos/farmacologia , Epigênese Genética/fisiologia , Éxons , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Doença Trofoblástica Gestacional/metabolismo , Doença Trofoblástica Gestacional/patologia , Humanos , Ácidos Hidroxâmicos/farmacologia , Fator 3 de Transcrição de Octâmero/metabolismo , Placenta/patologia , Gravidez , Regiões Promotoras Genéticas , RNA Mensageiro/metabolismoRESUMO
AIMS: Hydatidiform mole (HM) is the most common type of gestational trophoblastic disease. A proportion of patients with HM develop gestational trophoblastic neoplasia (GTN) requiring chemotherapy. The aim was to identify differentially expressed genes that are associated with development of GTN. METHODS AND RESULTS: Using cDNA microarray, differential expression of prostate stem cell antigen (PSCA) was identified in HMs that developed GTN compared with those that spontaneously regressed. Significant overexpression of PSCA RNA (P = 0.037) and protein (P < 0.05) in aggressive HM was verified by real-time polymerase chain reaction (PCR) and immunohistochemical analysis in 10 first-trimester placentas, 36 HM that subsequently regressed and 11 HM that developed GTN. A high level of PSCA expression was also found in three choriocarcinomas and three placental site trophoblastic tumours. A positive correlation was observed between PSCA expression and proliferation and apoptotic indices as assessed by Ki67 (P = 0.01), mcm7 (P = 0.001) and M30 (P = 0.016), as well as p53 (P < 0.01), p21(WAF1/CIP1) (P < 0.01) and mdm2 (P = 0.002) expression. CONCLUSIONS: Overexpression of PSCA is associated with development of GTN in HM. PSCA probably plays a role in the regulation of cell growth through p53-related signaling pathways.
Assuntos
Doença Trofoblástica Gestacional/metabolismo , Mola Hidatiforme/metabolismo , Glicoproteínas de Membrana/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias da Próstata/metabolismo , Adolescente , Adulto , Antígenos de Neoplasias , Biomarcadores Tumorais/metabolismo , Proliferação de Células , DNA de Neoplasias/genética , Feminino , Proteínas Ligadas por GPI , Regulação Neoplásica da Expressão Gênica , Doença Trofoblástica Gestacional/genética , Doença Trofoblástica Gestacional/patologia , Humanos , Mola Hidatiforme/genética , Mola Hidatiforme/patologia , Masculino , Glicoproteínas de Membrana/genética , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , Análise de Sequência com Séries de Oligonucleotídeos , Gravidez , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Transdução de Sinais/genética , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismoRESUMO
AIMS: To assess the expression profile of the activated form of signal transducer and activator of transcription (Stat)3 in gestational trophoblastic disease (GTD) and correlate the findings with clinicopathological parameters. METHODS AND RESULTS: By immunohistochemistry, both cytoplasmic and nuclear expression of p-Stat3-Ser(727) was demonstrated in 88 trophoblastic tissues, including placentas and GTD. Nuclear immunoreactivity of p-Stat3-Ser(727) was significantly higher in hydatidiform mole (HM) (P < 0.001) and choriocarcinoma (P = 0.009) when compared with normal placentas. Placental site trophoblastic tumours (PSTT) and epithelioid trophoblastic tumours (ETT) also demonstrated higher nuclear p-Stat3-Ser(727) expression than their normal trophoblast counterparts. Higher p-Stat3-Ser(727) expression was confirmed in choriocarcinoma cell lines, JEG-3 and JAR, than in a normal trophoblast cell line, with both nuclear and cytoplasmic fractions demonstrated by immunoblotting. Spontaneously regressed HM showed significantly increased nuclear and cytoplasmic p-Stat3-Ser(727) immunoreactivity over those that developed gestational trophoblastic neoplasia (GTN) (P = 0.013, P = 0.039). There was a significant positive and inverse correlation between nuclear p-Stat3-Ser(727) immunoreactivity and apoptotic indices [terminal deoxynucleotidyl transferase (TdT)-mediated deoxyuridine triphosphate (dUTP) nick end labelling and M30 CytoDeath antibody] (P = 0.001, P < 0.001, Spearman's rho test) and Bcl-2 expression (P = 0.034), respectively. CONCLUSIONS: p-Stat3-Ser(727) plays a role in the pathogenesis of GTD, probably through the regulation of apoptosis. p-Stat3-Ser(727) immunoreactivity is a potential marker in predicting GTN in HM.
Assuntos
Apoptose/fisiologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Tumor Trofoblástico de Localização Placentária/metabolismo , Tumor Trofoblástico de Localização Placentária/patologia , Neoplasias Uterinas/metabolismo , Neoplasias Uterinas/patologia , Apoptose/genética , Linhagem Celular , Linhagem Celular Tumoral , Feminino , Humanos , Imuno-Histoquímica , Fosforilação , Gravidez , Fator de Transcrição STAT3/biossíntese , Tumor Trofoblástico de Localização Placentária/genética , Neoplasias Uterinas/genéticaRESUMO
OBJECTIVES: To explore perceptions towards cervical cancer, human papillomavirus (HPV) infection and HPV vaccination and to identify factors affecting the acceptability of HPV vaccination among Chinese adolescent girls in Hong Kong. METHODS: Six focus groups were conducted with Chinese adolescent girls (median age 16 years, age range 13-20, n = 64) in Hong Kong in April 2007. Thematic analysis was employed to identify major themes related to cervical cancer and HPV vaccination. A supplementary questionnaire was administered to all participants before and after group discussion to assess their knowledge, attitudes and intention to be vaccinated and to collect demographic information. RESULTS: Participants' knowledge on cervical cancer was limited and HPV was largely unheard of. They had difficulty understanding the mechanism linking cervical cancer with HPV infection. Participants held a favourable attitude towards HPV vaccination but the perceived timing of vaccination varied. Barriers to vaccination include high monetary cost, uncertain length of vaccine effectiveness, low perceived risk of HPV infection, no immediate perceived need of vaccination, anticipated family disapproval and fear of the pain of injection. Factors conducive to vaccination include perceived family and peer support and medical reassurance on safety and efficacy of vaccine. The differences on knowledge, attitudes, intention to be vaccinated now and willingness to conform to significant others before and after the discussion were statistically significant, with an increased tendency towards favouring vaccination after the focus group. CONCLUSIONS: Participants favoured HPV vaccination despite not feeling an immediate need to be vaccinated. Interventions could focus on providing professional information on HPV vaccination and raising adolescents' perceived need to take preventive measures against HPV infection.
Assuntos
Povo Asiático/etnologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , Adolescente , Adulto , Feminino , Grupos Focais , Hong Kong/epidemiologia , Humanos , Infecções por Papillomavirus/etnologia , Neoplasias do Colo do Útero/psicologiaRESUMO
PURPOSE: Promoter hypermethylation is a common phenomenon in neoplasm. The aims of this study were (a) to compare the methylation profiles in different types of ovarian tumors and (b) to determine the possible relationship between the methylation status and different clinicopathologic characteristics. METHODS: We examined the promoter methylation status of 9 tumor suppressor genes (RARbeta2, TMS1, RIZ1, P15, P16, PTEN, MINT31, APC and HIC1) in 89 ovarian cancers, 16 borderline ovarian tumors, 19 benign ovarian tumors, 16 normal ovarian tissue and 5 ovarian cancer cell lines. The methylation status was examined with respect to clinicopathologic characteristics of the ovarian cancer patients. RESULTS: Methylation indices for ovarian cancer, borderline ovarian tumor, benign ovarian tumor, normal ovarian tissue and ovarian cancer cell lines were 28.8, 20.1, 10.5, 11.8 and 42.2%, respectively. It was significantly higher in ovarian cancer, borderline ovarian tumor and ovarian cancer cell lines (X (2) test, P < 0.001, P = 0.01 and P < 0.001, respectively) than benign or normal ovarian tissues. In ovarian cancer, concurrent methylation of at least two genes (CM2) was associated with early stage disease (X (2) test, P = 0.035) and less recurrence (X (2) test, P = 0.020). When the methylation statuses of the nine genes as well as CM2 were included in multivariate Cox Regression analysis, CM2 was the only independent predictor for survival (P = 0.013). CONCLUSION: CM2 was an independent predictor for survival in ovarian cancer.
Assuntos
Metilação de DNA , Neoplasias Ovarianas/genética , Linhagem Celular Tumoral , Feminino , Genes Supressores de Tumor , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Neoplasias Ovarianas/metabolismo , Ovário/metabolismo , Análise de SobrevidaRESUMO
Complete hydatidiform mole (CHM) is a type of gestational trophoblastic disease with pure paternal chromosome contribution and unpredictable malignant potential. As an attempt to assess the molecular pathogenesis of CHM, suppression subtractive hybridization (SSH) combined with cDNA microarray was used to compare the gene expression pattern of CHM compared with normal first-trimester placenta of similar gestational ages. cDNA microarray analysis using tissue-specific chips constructed with subtracted cDNA libraries identified 13 differentially expressed gene transcripts. Quantitative real-time polymerase chain reaction (PCR) confirmed up-regulation of human chorionic gonadotropin beta subunit (CGB) (P=0.0008) and KIAA1200 (P=0.0005), a G-protein regulator, as well as down-regulation of osteopontin (SPP1) (P<0.0001) in 14 genotyped CHM when compared with 15 normal placentas. These candidate genes may contribute toward understanding the mechanism involved with the development and progression of CHM.
Assuntos
Mola Hidatiforme/metabolismo , Adulto , Estudos de Casos e Controles , Gonadotropina Coriônica Humana Subunidade beta/metabolismo , Regulação para Baixo , Feminino , Proteínas de Ligação ao GTP/metabolismo , Perfilação da Expressão Gênica/métodos , Humanos , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Osteopontina , Placenta/metabolismo , Reação em Cadeia da Polimerase , Gravidez , Trimestres da Gravidez , Análise de Sequência de DNA , Sialoglicoproteínas/metabolismo , Regulação para CimaRESUMO
BACKGROUND: Placental trophoblast can be considered to be pseudomalignant tissue and the pathogenesis of gestational trophoblastic diseases remains to be clarified. AIMS: To examine the role of caspases 8 and 10, identified by differential expression, on trophoblast tumorigenesis. METHODS: cDNA array hybridisation was used to compare gene expression profiles in choriocarcinoma cell lines (JAR, JEG, and BeWo) and normal first trimester human placentas, followed by confirmation with quantitative real time polymerase chain reaction and immunohistochemistry. Caspase 10 and its closely related family member caspase 8 were analysed. RESULTS: Downregulation of caspase 10 in choriocarcinoma was detected by both Atlastrade mark human cDNA expression array and Atlastrade mark human 1.2 array. Caspase 10 mRNA expression was significantly lower in hydatidiform mole (p = 0.035) and chorioarcinoma (p = 0.002) compared with normal placenta. The caspase 8 and 10 proteins were expressed predominantly in the cytotrophoblast and syncytiotrophoblast, respectively, with significantly lower expression in choriocarcinomas than other trophoblastic tissues (p < 0.05). Immunoreactivity for both caspase 8 and 10 correlated with the apoptotic index previously assessed by terminal deoxynucleotidyl transferase mediated dUTP nick end labelling (p = 0.02 and p = 0.04, respectively) and M30 (p < 0.001 and p = 0.003, respectively) approaches. CONCLUSIONS: These results suggest that the downregulation of capases 8 and 10 might contribute to the pathogenesis of choriocarcinoma.
Assuntos
Caspases/biossíntese , Coriocarcinoma/enzimologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Uterinas/enzimologia , Apoptose , Caspase 10 , Caspase 8 , Caspases/genética , Coriocarcinoma/patologia , DNA de Neoplasias/genética , Regulação para Baixo , Feminino , Perfilação da Expressão Gênica/métodos , Humanos , Mola Hidatiforme/enzimologia , Mola Hidatiforme/patologia , Hibridização de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos , Placenta/enzimologia , Gravidez , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Células Tumorais Cultivadas , Neoplasias Uterinas/patologiaRESUMO
BACKGROUND: All-trans retinoic acid (ATRA) is a natural vitamin A derivative that has a profound effect on the regulation of cell growth, differentiation and death. AIM: To investigate the tissue dynamic and cellular invasion effects of ATRA in choriocarcinoma (CCA), an aggressive trophoblastic tumour, by using a three-dimensional organotypic culture model system and cell invasion assay, respectively. METHODS: An organotypic culture model of two CCA cell lines, JAR and JEG, was established. The effects of 1 microM ATRA on proliferation, differentiation and apoptosis on this CCA model were assessed by morphological assessment of the mitotic and apoptotic figures as well as by Ki-67 and caspase-related M30 cytoDeath antibody immunohistochemistry and the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end labelling (TUNEL) assay. The effect of ATRA on p53 and its regulated protein product, WAF1/Cip1, was also evaluated with DO7 and p21(WAF1) antibodies, respectively. Moreover, the effect of ATRA on cellular (CCA) invasion was also investigated with Cell Invasion Kit on the JEG cell line. RESULTS: ATRA was found to induce marked apoptosis in organotypic cultures of both cell lines, as evidenced by increased M30-positive cells (p<0.0001) and increased TUNEL-positive cells (p<0.0001) in treated cultures; to decrease proliferation, as evidenced by decreased Ki-67-positive cells (p<0.0001); and to decrease p53-DO7 immunoreactivity (p<0.0001) and increase p21(WAF1) (p<0.0001) immunoreactivity. 1.5 microM ATRA was found to effectively inhibit JEG cell invasion in the cell invasion assay. CONCLUSION: ATRA treatment was found to inhibit invasion and proliferation and enhance apoptosis, probably by the activation of caspases and induction of differentiation. ATRA and synthetic retinoids may be alternative agents for the treatment of CCA.
Assuntos
Antineoplásicos/farmacologia , Coriocarcinoma/patologia , Tretinoína/farmacologia , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Coriocarcinoma/metabolismo , Relação Dose-Resposta a Droga , Humanos , Marcação In Situ das Extremidades Cortadas/métodos , Proteína Supressora de Tumor p53/metabolismoRESUMO
Gestational trophoblastic disease (GTD) is a heterogeneous group of diseases characterized by abnormally proliferating trophoblastic tissues. This includes partial and complete hydatidiform moles, invasive mole, choriocarcinoma and placental site trophoblastic tumour. Cytogenetic studies revealed that hydatidiform moles contain either solely (as in complete moles) or an excess (as in partial moles) of paternal contribution to the genome. Genomic imprinting is believed to play a pivotal role in the pathogenesis of hydatidiform moles. However its precise role and mechanism remains poorly understood. Hydatidiform mole carries a potential of malignant transformation. Similar to other human cancers, malignant transformation in gestational trophoblastic tumours is likely a multistep process and involves multiple genetic alterations including activation of oncogenes and inactivation of tumour suppressor genes. In addition, expression of telomerase activity, altered expression of cell--cell adhesion molecules and abnormal expression of matrix metalloproteinases have also been reported in GTD. These represent disruption of the delicate balance and regulation of cellular processes including proliferation, differentiation, apoptosis and invasion. The significance of these alterations in the pathogenesis and malignant transformation of gestational trophoblastic diseases is reviewed in this paper.
Assuntos
Coriocarcinoma/genética , Mola Hidatiforme Invasiva/genética , Tumor Trofoblástico de Localização Placentária/genética , Adulto , Coriocarcinoma/patologia , Análise Citogenética , Feminino , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Impressão Genômica , Humanos , Mola Hidatiforme Invasiva/patologia , Biologia Molecular , Oncogenes , Gravidez , Telomerase , Tumor Trofoblástico de Localização Placentária/patologiaRESUMO
AIMS: To assess the potential value of chromosome in situ hybridisation (CISH), Ki-67, and telomerase immunocytochemistry in liquid based cervical cytology to help detect carcinoma cells and precursors. METHOD: Sixty ThinPrep processed cervical cytology samples were studied: 23 cases within the normal limit, 13 low grade squamous intraepithelial lesions (LSILs), 10 high grade squamous intraepithelial lesions (HSILs), six squamous cell carcinomas, three endocervical adenocarcinomas, two cervical adenosquamous cell carcinomas, and three endometrial adenocarcinomas. CISH was performed with DNA probes specific for the pericentromeric regions of chromosome 11 and 16. Hybridisation signals were visualised with the streptavidin-biotin peroxidase technique. The monoclonal MIB1 and polyclonal TRT-H231 antibodies were used to detect Ki-67 and telomerase immunoreactivity, respectively. RESULTS: Non-specific background staining was almost absent in CISH slides. Normal squamous and glandular cells showed a diploid chromosomal pattern. A relative gain in chromosomes 11 and 16 (aneusomy) was seen in HSIL and the carcinomas (p<0.0001). In MIB1 stained smears, normal cells and koilocytes showed inconspicuous immunoreactivity, whereas strongly immunoreactive nuclei were found in cancer cells and HSIL (p<0.0001). Not only carcinoma and HSIL cells, but also some normal cells, showed cytoplasmic staining for telomerase. CONCLUSIONS: These preliminary results indicate that ThinPrep processed cervical smears are suitable for CISH and immunocytochemical studies. The neoplastic squamous and glandular cells were easily identified based on nuclear aneusomy and strong Ki-67 immuoreactivity in the context of abnormal nuclear morphology. This is the first study to apply CISH in cervical cytology using an immunoenzymatic approach.
Assuntos
Biomarcadores Tumorais/metabolismo , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 16/genética , Hibridização In Situ/métodos , Neoplasias do Colo do Útero/diagnóstico , Esfregaço Vaginal/métodos , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/genética , Feminino , Humanos , Técnicas Imunoenzimáticas , Antígeno Ki-67/metabolismo , Telomerase/metabolismo , Neoplasias do Colo do Útero/genética , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/genéticaRESUMO
Sixteen cases of primary carcinoma of the fallopian tube were diagnosed and treated at Queen Mary Hospital, Hong Kong from July 1972 to June 1992 constituting 0.26% of the total gynecologic malignancies seen during that period. The average age was 61 years and the most common presenting symptom was abnormal vaginal bleeding. Preoperative diagnosis is difficult; in only one case was a diagnosis of malignancy made by cervical smear. An adnexal mass was detected in 13 of the cases (81.3%) either by clinical examination and/or ultrasonography. Therapy consisted of surgical resection, usually followed by various combinations of adjuvant radiation therapy and chemotherapy. The cumulative survival was 62%. In addition to the typical form of adenocarcinoma, one case of squamous cell carcinoma and a case of multifocal endometrioid adenocarcinoma were observed. One case of an apparently usual form of adenocarcinoma recurred as a heterologous malignant mixed Müllerian tumor 2 years after diagnosis. This series further emphasises the wide range of differentiation possible in the Müllerian system and the variety of neoplasms which may arise from it.
RESUMO
The role of p53 in the pathogenesis of gestational trophoblastic disease (GTD) was investigated. Immunohistochemical studies for p53, its regulator mdm2, and proliferation marker Ki67 were performed on paraffin-embedded tissues of 28 partial moles (PM), 57 complete moles (CM), 14 choriocarcinomas (CCA), and 31 normal placentas. Three antibodies to p53 (DO-7, Ab-2, Ab-3) were used and demonstrated immunoreactivity for wild-type p53 protein predominantly in the nuclei of cytotrophoblasts. Direct DNA sequencing of 36 hydatidiform moles using frozen tissues confirmed an absence of mutational changes in exons 5-8. CCA was found to have the highest p53 protein expression, followed by CM, PM, and normal placenta (P < 0.001). In normal placentas (P = 0.0001), PM, and CM (P = 0.016), an inverse correlation between their gestational age and p53 expression was observed. p53 expression was found to correlate with proliferation index in normal placenta (P = 0.0001) and all three groups of GTD (P = 0.012). Significant correlation between p53 and mdm2 expression was also observed (P < 0.01). The distinctive expression of p53 wild-type protein in the cytotrophoblasts and its positive correlation with the proliferative index suggests that its overexpression in GTD may be related to its effect on cell proliferation. The parallel expression of mdm2 and p53 also supports the presence of an autoregulatory feedback loop in the control of this process. No correlation could be found between clinical progress of the patients with hydatidiform moles, and the p53 (P = 0.78) or mdm2 protein (P = 0.54) expression suggesting that neither of them carries any prognostic significance.