RESUMO
BACKGROUND: Ovarian cancer is the most lethal gynecological cancer which is characterized by extensive peritoneal implantation metastasis and malignant ascites. Despite advances in diagnosis and treatment in recent years, the five-year survival rate is only 25-30%. Therefore, developing multifunctional nanomedicine with abilities of promoting apoptosis and inhibiting migration on tumor cells would be a promising strategy to improve the antitumor effect. METHODS AND RESULTS: In this study, we developed a novel ACaT nanomedicine composed of alendronate, calcium ions and cyclin-dependent kinase 7 (CDK7) inhibitor THZ1. With the average size of 164 nm and zeta potential of 12.4 mV, the spherical ACaT nanoparticles were selectively internalized by tumor cells and effectively accumulated in the tumor site. Results of RNA-sequencing and in vitro experiments showed that ACaT promoted tumor cell apoptosis and inhibited tumor cell migration by arresting the cell cycle, increasing ROS and affecting calcium homeostasis. Weekly intraperitoneally administered of ACaT for 8 cycles significantly inhibited the growth of tumor and prolonged the survival of intraperitoneal xenograft mice. CONCLUSION: In summary, this study presents a new self-assembly nanomedicine with favorable tumor targeting, antitumor activity and good biocompatibility, providing a novel therapeutic strategy for advanced ovarian cancer.
Assuntos
Nanomedicina , Neoplasias Ovarianas , Animais , Apoptose , Linhagem Celular Tumoral , Humanos , Camundongos , Neoplasias Ovarianas/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Fusobacterium nucleatum (F. nucleatum), which has been associated with colorectal carcinogenesis, can impair anti-tumour immunity, and actively invade colon epithelial cells. Considering the critical role of autophagy in host defence against microorganisms, we hypothesised that autophagic activity of tumour cells might influence the amount of F. nucleatum in colorectal cancer tissue. Using 724 rectal and colon cancer cases within the Nurses' Health Study and the Health Professionals Follow-up Study, we evaluated autophagic activity of tumour cells by immunohistochemical analyses of BECN1 (beclin 1), MAP1LC3 (LC3), and SQSTM1 (p62) expression. We measured the amount of F. nucleatum DNA in tumour tissue by quantitative polymerase chain reaction (PCR). We conducted multivariable ordinal logistic regression analyses to examine the association of tumour BECN1, MAP1LC3, and SQSTM1 expression with the amount of F. nucleatum, adjusting for potential confounders, including microsatellite instability status; CpG island methylator phenotype; long-interspersed nucleotide element-1 methylation; and KRAS, BRAF, and PIK3CA mutations. Compared with BECN1-low cases, BECN1-intermediate and BECN1-high cases were associated with lower amounts of F. nucleatum with odds ratios (for a unit increase in three ordinal categories of the amount of F. nucleatum) of 0.54 (95% confidence interval, 0.29-0.99) and 0.31 (95% confidence interval, 0.16-0.60), respectively (Ptrend < 0.001 across ordinal BECN1 categories). Tumour MAP1LC3 and SQSTM1 levels were not significantly associated with the amount of F. nucleatum (Ptrend > 0.06). Tumour BECN1, MAP1LC3, and SQSTM1 levels were not significantly associated with patient survival (Ptrend > 0.10). In conclusion, tumour BECN1 expression is inversely associated with the amount of F. nucleatum in colorectal cancer tissue, suggesting a possible role of autophagy in the elimination of invasive microorganisms. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.
Assuntos
Autofagia/genética , Neoplasias Colorretais/genética , Fusobacterium nucleatum/genética , Microambiente Tumoral/genética , Idoso , Biomarcadores Tumorais/genética , Carcinogênese/genética , Carcinogênese/patologia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Neoplasias Colorretais/imunologia , Feminino , Fusobacterium nucleatum/imunologia , Humanos , Masculino , Instabilidade de Microssatélites , Mutação/genéticaRESUMO
BACKGROUND: A preventive potential of high calcium intake against colorectal cancer has been indicated for distal colon cancer, which is inversely associated with high-level CpG island methylator phenotype (CIMP), high-level microsatellite instability (MSI), and BRAF and PIK3CA mutations. In addition, BRAF mutation is strongly inversely correlated with KRAS mutation. We hypothesized that the association between calcium intake and colon cancer risk might vary by these molecular features. METHODS: We prospectively followed 88,506 women from the Nurses' Health Study and 47,733 men from the Health Professionals Follow-up Study for up to 30 years. Duplication-method Cox proportional cause-specific hazards regression was used to estimate multivariable hazard ratios (HRs), and 95% confidence intervals (95% CIs) for the associations between calcium intake and the risk of colon cancer subtypes. By Bonferroni correction, the α-level was adjusted to 0.01. RESULTS: Based on 853 colon cancer cases, the inverse association between dietary calcium intake and colon cancer risk differed by CIMP status (pheterogeneity = 0.01). Per each 300 mg/day increase in intake, multivariable HRs were 0.84 (95% CI 0.76-0.94) for CIMP-negative/low and 1.12 (95% CI 0.93-1.34) for CIMP-high. Similar differential associations were suggested for MSI subtypes (pheterogeneity = 0.02), with the corresponding HR being 0.86 (95% CI 0.77-0.95) for non-MSI-high and 1.10 (95% CI 0.92-1.32) for MSI-high. No differential associations were observed by BRAF, KRAS, or PIK3CA mutations. CONCLUSION: The inverse association between dietary calcium intake and colon cancer risk may be specific to CIMP-negative/low and possibly non-MSI-high subtypes.
Assuntos
Cálcio/administração & dosagem , Neoplasias do Colo/patologia , Ilhas de CpG/genética , Proteínas Proto-Oncogênicas B-raf/genética , Idoso , Neoplasias do Colo/genética , Metilação de DNA , Feminino , Seguimentos , Humanos , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Mutação , Fenótipo , Modelos de Riscos Proporcionais , RiscoRESUMO
PURPOSE: Germline variants in double-strand DNA damage repair (dsDDR) genes (e.g., BRCA1/2) predispose to pancreatic adenocarcinoma (PDAC) and may predict sensitivity to platinum-based chemotherapy and poly(ADP) ribose polymerase (PARP) inhibitors. We sought to determine the prevalence and significance of germline cancer susceptibility gene variants in PDAC with paired somatic and survival analyses. METHODS: Using a customized next-generation sequencing panel, germline/somatic DNA was analyzed from 289 patients with resected PDAC ascertained without preselection for high-risk features (e.g., young age, personal/family history). All identified variants were assessed for pathogenicity. Outcomes were analyzed using multivariable-adjusted Cox proportional hazards regression. RESULTS: We found that 28/289 (9.7%; 95% confidence interval [CI] 6.5-13.7%) patients carried pathogenic/likely pathogenic germline variants, including 21 (7.3%) dsDDR gene variants (3 BRCA1, 4 BRCA2, 14 other dsDDR genes [ATM, BRIP1, CHEK2, NBN, PALB2, RAD50, RAD51C]), 3 Lynch syndrome, and 4 other genes (APC p.I1307K, CDKN2A, TP53). Somatic sequencing and immunohistochemistry identified second hits in the tumor in 12/27 (44.4%) patients with germline variants (1 failed sequencing). Compared with noncarriers, patients with germline dsDDR gene variants had superior overall survival (hazard ratio [HR] 0.54; 95% CI 0.30-0.99; P = 0.05). CONCLUSION: Nearly 10% of PDAC patients harbor germline variants, although the majority lack somatic second hits, the therapeutic significance of which warrants further study.
Assuntos
Adenocarcinoma/genética , Predisposição Genética para Doença , Proteínas de Neoplasias/genética , Neoplasias Pancreáticas/genética , Adenocarcinoma/epidemiologia , Adenocarcinoma/patologia , Adenocarcinoma/cirurgia , Adulto , Idoso , Quebras de DNA de Cadeia Dupla , Intervalo Livre de Doença , Etnicidade/genética , Feminino , Mutação em Linhagem Germinativa/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/cirurgiaRESUMO
BACKGROUND Baicalin, one of the main bioactive components extracted from the traditional Chinese medicine baical Skullcap root, has an anti-tumor activity which had been studied in several cancers. However, its role in human mesothelioma remains unknown. In this study, we investigated the anti-tumor mechanisms of baicalin in the mesothelioma cell line MESO924. MATERIAL AND METHODS Effects of baicalin on mesothelioma were assessed by measuring cell viability, apoptosis, migration, invasion, inactivation of signaling intermediates, and cell-cycle alterations. RESULTS Baicalin inhibited the proliferation, migration, and invasion of human mesothelioma cells and increased their apoptosis, all in a dose-dependent manner. Specifically, baicalin decreased the expression of p-EGFR, p-AKT, p-MAPK, p-S6, Bcl-2, and VEGF and increased the expression of Bax in mesothelioma cells. The suppressed mesothelioma cellular proliferation is due to the arrest of the S cell cycle by baicalin. Inhibition of the PI3K/AKT/mTOR signaling pathway by a PI3K/AKT/mTOR inhibitor augmented the anti-proliferation effects induced by baicalin. In addition, baicalin increased the sensitivity of MESO924 to the chemotherapeutic drugs doxorubicin, cisplatin, and pemetrexed. CONCLUSIONS These results highlight the roles of baicalin in inhibiting cell growth, migration, and invasion of mesothelioma cells while increasing apoptosis and sensitizing cells to chemotherapeutic agents through the PI3K/AKT/mTOR signaling pathway, which indicates that baicalin could be a useful drug for mesothelioma therapy.
Assuntos
Flavonoides/farmacologia , Mesotelioma/tratamento farmacológico , Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , China , Flavonoides/metabolismo , Flavonoides/uso terapêutico , Humanos , Invasividade Neoplásica/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismoRESUMO
OBJECTIVE: Although evidence suggests an inverse association between calcium intake and the risk of colorectal cancer, the mechanisms remain unclear. The calcium-sensing receptor (CASR) is expressed abundantly in normal colonic epithelium and may influence carcinogenesis. We hypothesized that calcium intake might be associated with lower risk of CASR-positive, but not CASR-negative, colorectal cancer. DESIGN: We assessed tumour CASR protein expression using immunohistochemistry in 779 incident colon and rectal cancer cases that developed among 136 249 individuals in the Nurses' Health Study and Health Professionals Follow-Up Study. Duplication method Cox proportional hazards regression analysis was used to assess associations of calcium intake with incidence of colorectal adenocarcinoma subtypes by CASR status. RESULTS: Total calcium intake was inversely associated with the risk of developing colorectal cancer (ptrend=0.01, comparing ≥1200 vs <600 mg/day: multivariable HR=0.75, 95% CI 0.60 to 0.95). For the same comparison, higher total calcium intake was associated with a lower risk of CASR-positive tumours (ptrend=0.003, multivariable HR=0.67, 95% CI 0.51 to 0.86) but not with CASR-negative tumours (ptrend=0.67, multivariable HR=1.15, 95% CI 0.75 to 1.78; pheterogeneity=0.06 between the CASR subtypes). The stronger inverse associations of calcium intake with CASR-positive but not CASR-negative tumours generally appeared consistent regardless of sex, tumour location and source of calcium. CONCLUSIONS: Our molecular pathological epidemiology data suggest a causal relationship between higher calcium intake and lower colorectal cancer risk, and a potential role of CASR in mediating antineoplastic effect of calcium.
Assuntos
Cálcio da Dieta/administração & dosagem , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/metabolismo , Dieta , Receptores de Detecção de Cálcio/metabolismo , Adulto , Idoso , Estudos de Coortes , Neoplasias Colorretais/diagnóstico , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
BACKGROUND & AIMS: Western and prudent dietary patterns have been associated with higher and lower risks of colorectal cancer (CRC), respectively. However, little is known about the associations between dietary patterns and specific anatomic subsites or molecular subtypes of CRC. METHODS: We used multivariable Cox proportional hazards models to examine the associations between Western and prudent dietary patterns and CRC risk in the Health Professionals Follow-up Study and Nurses' Health Study. RESULTS: After up to 32 years of follow-up of 137,217 men and women, we documented 3260 cases of CRC. Among individuals from whom subsite data were available, we observed 1264 proximal colon, 866 distal colon, and 670 rectal tumors. Western diet was associated with an increased incidence of CRC (Ptrend < .0001), with a relative risk (RR) of 1.31 (95% CI, 1.15-1.48, comparing the highest to lowest quartile). The association of Western diet with CRC was evident for tumors of the distal colon (RR, 1.55; 95% CI, 1.22-1.96; Ptrend = .0004) and rectum (RR, 1.35; 95% CI, 1.03-1.77; Ptrend = .01) but not proximal colon (RR, 1.11; 95% CI, 0.91-1.35; Ptrend = .51) when we comparing extreme quartiles. In contrast, for the prudent pattern, we observed a RR of 0.86 for overall CRC (95% CI, 0.77-0.95; Ptrend = .01), with similar trends at anatomic subsites. However, the trend appeared stronger among men than women. Among 1285 cases (39%) with tissue available for molecular profiling, Western diet appeared to be more strongly associated with some CRC molecular subtypes (no mutations in KRAS [KRAS wildtype] or BRAF [BRAF wildtype], no or a low CpG island methylator phenotype, and microsatellite stability), although formal tests for heterogeneity did not produce statistically significant results. CONCLUSIONS: Western dietary patterns are associated with an increased risk of CRC, particularly distal colon and rectal tumors. Western dietary patterns also appear more strongly associated with tumors that are KRAS wildtype, BRAF wildtype, have no or a low CpG island methylator phenotype, and microsatellite stability. In contrast, prudent dietary patterns are associated with a lower risk of CRC that does not vary according to anatomic subsite or molecular subtype.
Assuntos
Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/prevenção & controle , Dieta Saudável , Dieta Ocidental/efeitos adversos , Comportamento Alimentar , Comportamento de Redução do Risco , Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Ilhas de CpG , Metilação de DNA , Feminino , Humanos , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Epidemiologia Molecular , Análise Multivariada , Mutação , Enfermeiras e Enfermeiros , Razão de Chances , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Proteção , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Medição de Risco , Fatores de Risco , Inquéritos e Questionários , Fatores de Tempo , Estados Unidos/epidemiologiaRESUMO
BACKGROUND & AIMS: Statin medications, most commonly prescribed to reduce lipid levels and prevent cardiovascular disease, may be associated with longer survival times of patients with cancer. However, the association of statins with outcomes of patients with pancreatic adenocarcinoma is not clear. METHODS: We analyzed the association of statin use before a diagnosis of pancreatic cancer with survival times of 648 participants in the Nurses' Health Study and Health Professionals Follow-up Study who were diagnosed with pancreatic adenocarcinoma from 2000 through 2013. We estimated hazard ratios (HRs) for overall mortality using Cox proportional hazards models with adjustment for potential confounders. We assessed the temporal association between prediagnosis statin use and cancer survival by 2-year lag periods to account for a possible latency period between statin use and cancer survival. RESULTS: Regular statin use before diagnosis of pancreatic cancer was associated with modestly prolonged survival compared with nonregular use (adjusted HR, 0.82; 95% CI, 0.69-0.97; P = .02). A 1-month longer median survival was observed in regular statin users compared with nonregular users. Regular statin use within the 2 years prior to cancer diagnosis was most strongly associated with longer survival. We observed no statistically significant effect modification by smoking status, body mass index, diabetes, or cancer stage (all Pinteraction > .53). Regular statin use before diagnosis was similarly associated with survival in the Nurses' Health Study (HR, 0.79; 95% CI, 0.64-0.97) and Health Professionals Follow-up Study (HR, 0.86; 95% CI, 0.63-1.15). CONCLUSIONS: Regular statin use before diagnosis of pancreatic cancer was associated with modest increases in survival times in 2 large prospective cohort studies.
Assuntos
Adenocarcinoma/mortalidade , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Neoplasias Pancreáticas/mortalidade , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Sobrevida , Resultado do TratamentoRESUMO
BACKGROUND & AIMS: Dietary patterns affect systemic and local intestinal inflammation, which have been linked to colorectal carcinogenesis. Chronic inflammation can interfere with the adaptive immune response. We investigated whether the association of a diet that promotes intestinal inflammation with risk of colorectal carcinoma was stronger for tumors with lower lymphocytic reactions than tumors with higher lymphocytic reactions. METHODS: We collected data from the molecular pathological epidemiology databases of 2 prospective cohort studies: the Nurses' Health Study (since 1976) and the Health Professionals Follow-Up Study (since 1986). We used duplication-method time-varying Cox proportional cause-specific hazards regression to assess the association of empirical dietary inflammatory pattern (EDIP) score (derived from food frequency questionnaire data) with colorectal carcinoma subtype. Foods that contribute to high EDIP scores include red and processed meats, refined grains, carbonated beverages, and some vegetables; foods that contribute to low EDIP scores include beer, wine, coffee, tea, yellow and leafy vegetables, and fruit juice. Colorectal tissue samples were analyzed histologically for patterns of lymphocytic reactions (Crohn's-like lymphoid reaction, peritumoral lymphocytic reaction, intratumoral periglandular reaction, and tumor-infiltrating lymphocytes). RESULTS: During follow-up of 124,433 participants, we documented 1311 incident colon and rectal cancer cases with available tissue data. The association between the EDIP and colorectal cancer risk was significant (Ptrend = .02), and varied with degree of peritumoral lymphocytic reaction (Pheterogeneity < .001). Higher EDIP scores were associated with increased risk of colorectal cancer with an absent or low peritumoral lymphocytic reaction (highest vs lowest EDIP score quintile hazard ratio, 2.60; 95% confidence interval, 1.60-4.23; Ptrend < .001), but not risk of tumors with intermediate or high peritumoral lymphocytic reaction (Ptrend > .80). CONCLUSIONS: In 2 prospective cohort studies, we associated inflammatory diets with a higher risk of colorectal cancer subtype that contains little or no peritumoral lymphocytic reaction. These findings suggest that diet-related inflammation might contribute to development of colorectal cancer, by suppressing the adaptive anti-tumor immune response.
Assuntos
Neoplasias Colorretais/imunologia , Dieta/efeitos adversos , Comportamento Alimentar , Doenças Inflamatórias Intestinais/imunologia , Linfócitos do Interstício Tumoral/imunologia , Evasão Tumoral , Adulto , Idoso , Biópsia , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/patologia , Bases de Dados Factuais , Feminino , Humanos , Incidência , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/epidemiologia , Masculino , Pessoa de Meia-Idade , Epidemiologia Molecular , Análise Multivariada , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Fatores de Risco , Fatores de Tempo , Estados Unidos/epidemiologiaRESUMO
BACKGROUND & AIMS: Specific nutritional components are likely to induce intestinal inflammation, which is characterized by increased levels of interleukin 6 (IL6), C-reactive protein (CRP), and tumor necrosis factor-receptor superfamily member 1B (TNFRSF1B) in the circulation and promotes colorectal carcinogenesis. The inflammatory effects of a diet can be estimated based on an empiric dietary inflammatory pattern (EDIP) score, calculated based on intake of 18 foods associated with plasma levels of IL6, CRP, and TNFRSF1B. An inflammatory environment in the colon (based on increased levels of IL6, CRP, and TNFRSF1B in peripheral blood) contributes to impairment of the mucosal barrier and altered immune cell responses, affecting the composition of the intestinal microbiota. Colonization by Fusobacterium nucleatum has been associated with the presence and features of colorectal adenocarcinoma. We investigated the association between diets that promote inflammation (based on EDIP score) and colorectal cancer subtypes classified by level of F nucleatum in the tumor microenvironment. METHODS: We calculated EDIP scores based on answers to food frequency questionnaires collected from participants in the Nurses' Health Study (through June 1, 2012) and the Health Professionals Follow-up Study (through January 31, 2012). Participants in both cohorts reported diagnoses of rectal or colon cancer in biennial questionnaires; deaths from unreported colorectal cancer cases were identified through the National Death Index and next of kin. Colorectal tumor tissues were collected from hospitals where the patients underwent tumor resection and F nucleatum DNA was quantified by a polymerase chain reaction assay. We used multivariable duplication-method Cox proportional hazard regression to assess the associations of EDIP scores with risks of colorectal cancer subclassified by F nucleatum status. RESULTS: During 28 years of follow-up evaluation of 124,433 participants, we documented 951 incident cases of colorectal carcinoma with tissue F nucleatum data. Higher EDIP scores were associated with increased risk of F nucleatum-positive colorectal tumors (Ptrend = .03); for subjects in the highest vs lowest EDIP score tertiles, the hazard ratio for F nucleatum-positive colorectal tumors was 1.63 (95% CI, 1.03-2.58). EDIP scores did not associate with F nucleatum-negative tumors (Ptrend = .44). High EDIP scores associated with proximal F nucleatum-positive colorectal tumors but not with proximal F nucleatum-negative colorectal tumors (Pheterogeneity = .003). CONCLUSIONS: Diets that may promote intestinal inflammation, based on EDIP score, are associated with increased risk of F nucleatum-positive colorectal carcinomas, but not carcinomas that do not contain these bacteria. These findings indicate that diet-induced intestinal inflammation alters the gut microbiome to contribute to colorectal carcinogenesis; nutritional interventions might be used in precision medicine and cancer prevention.
Assuntos
Colite/complicações , Colite/microbiologia , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/etiologia , Dieta/efeitos adversos , Infecções por Fusobacterium/complicações , Fusobacterium nucleatum/isolamento & purificação , Adulto , Idoso , Feminino , Seguimentos , Infecções por Fusobacterium/microbiologia , Humanos , Pessoa de Meia-IdadeRESUMO
Drug resistance presents a challenge to the treatment of cancer patients. Many studies have focused on cell-autonomous mechanisms of drug resistance. By contrast, we proposed that the tumour micro-environment confers innate resistance to therapy. Here we developed a co-culture system to systematically assay the ability of 23 stromal cell types to influence the innate resistance of 45 cancer cell lines to 35 anticancer drugs. We found that stroma-mediated resistance is common, particularly to targeted agents. We characterized further the stroma-mediated resistance of BRAF-mutant melanoma to RAF inhibitors because most patients with this type of cancer show some degree of innate resistance. Proteomic analysis showed that stromal cell secretion of hepatocyte growth factor (HGF) resulted in activation of the HGF receptor MET, reactivation of the mitogen-activated protein kinase (MAPK) and phosphatidylinositol-3-OH kinase (PI(3)K)-AKT signalling pathways, and immediate resistance to RAF inhibition. Immunohistochemistry experiments confirmed stromal cell expression of HGF in patients with BRAF-mutant melanoma and showed a significant correlation between HGF expression by stromal cells and innate resistance to RAF inhibitor treatment. Dual inhibition of RAF and either HGF or MET resulted in reversal of drug resistance, suggesting RAF plus HGF or MET inhibitory combination therapy as a potential therapeutic strategy for BRAF-mutant melanoma. A similar resistance mechanism was uncovered in a subset of BRAF-mutant colorectal and glioblastoma cell lines. More generally, this study indicates that the systematic dissection of interactions between tumours and their micro-environment can uncover important mechanisms underlying drug resistance.
Assuntos
Resistencia a Medicamentos Antineoplásicos , Fator de Crescimento de Hepatócito/metabolismo , Melanoma/metabolismo , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Microambiente Tumoral/fisiologia , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica , Linhagem Celular Tumoral , Técnicas de Cocultura , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Humanos , Indóis/farmacologia , Indóis/uso terapêutico , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , Terapia de Alvo Molecular , Mutação , Fosfatidilinositol 3-Quinases/metabolismo , Prognóstico , Inibidores de Proteínas Quinases/farmacologia , Inibidores de Proteínas Quinases/uso terapêutico , Proteômica , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Estromais/citologia , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , VemurafenibRESUMO
BACKGROUND Alteration of DNA methylation of tumor suppressor genes (TSGs) is one of the most consistent epigenetic changes in human cancers. DNMTs play several important roles in DNA methylation and development of cancers. Regarding DNMTs protein expressions, little is known about the clinical significance and correlation with promoter methylation status of TSGs in human pituitary adenomas. MATERIAL AND METHODS We analyzed the protein expression of 3 DNMTs using immunohistochemistry and assessed DNA hypermethylation of RASSF1A, CDH13, CDH1, and CDKN2A (p16) in 63 pituitary adenomas. We examined associations between DNMTs expression and clinicopathological features or promoter methylation status of TSGs. RESULTS Overexpression of DNMTs was detected in pituitary adenomas. Frequencies of DNMT1 overexpression were significantly higher in macroadenomas, invasive tumors, and grade III and IV tumors. DNMT3A was frequently detected in invasive tumors and grade IV tumors. In addition, DNMT1 and DNMT3A were frequently detected in high-methylation tumors. Furthermore, in multivariate logistic regression, the significant association between DNMT1 or DNMT3A and high-methylation status persisted after adjusting for clinicopathological features. CONCLUSIONS Our findings suggested that tumor overexpression of DNMT1 and DNMT3A is associated with tumor aggressive behavior and high-methylation status in pituitary adenomas. Our data support a possible role of DNMT1 and DNMT3A in TSG promoter methylation leading to pituitary adenoma invasion and suggest that inhibition of DNMTs has the potential to become a new therapeutic approach for invasive pituitary adenoma.
Assuntos
Adenoma/genética , DNA (Citosina-5-)-Metiltransferase 1/biossíntese , DNA (Citosina-5-)-Metiltransferases/biossíntese , Metilação de DNA , Genes Supressores de Tumor , Neoplasias Hipofisárias/genética , Adenoma/enzimologia , Adenoma/metabolismo , Adenoma/patologia , Adulto , Antígenos CD , Caderinas/genética , Caderinas/metabolismo , Inibidor p16 de Quinase Dependente de Ciclina , Inibidor de Quinase Dependente de Ciclina p18/genética , Inibidor de Quinase Dependente de Ciclina p18/metabolismo , DNA/metabolismo , DNA (Citosina-5-)-Metiltransferase 1/genética , DNA (Citosina-5-)-Metiltransferase 1/metabolismo , DNA (Citosina-5-)-Metiltransferases/genética , DNA (Citosina-5-)-Metiltransferases/metabolismo , DNA Metiltransferase 3A , Epigênese Genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Hipofisárias/enzimologia , Neoplasias Hipofisárias/metabolismo , Neoplasias Hipofisárias/patologia , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismoRESUMO
OBJECTIVE: Telomere shortening occurs as an early event in pancreatic tumorigenesis, and genetic variants at the telomerase reverse transcriptase (TERT) gene region have been associated with pancreatic cancer risk. However, it is unknown whether prediagnostic leucocyte telomere length is associated with subsequent risk of pancreatic cancer. DESIGN: We measured prediagnostic leucocyte telomere length in 386 pancreatic cancer cases and 896 matched controls from five prospective US cohorts. ORs and 95% CIs were calculated using conditional logistic regression. Matching factors included year of birth, cohort (which also matches on sex), smoking status, fasting status and month/year of blood collection. We additionally examined single-nucleotide polymorphisms (SNPs) at the TERT region in relation to pancreatic cancer risk and leucocyte telomere length using logistic and linear regression, respectively. RESULTS: Shorter prediagnostic leucocyte telomere length was associated with higher risk of pancreatic cancer (comparing extreme quintiles of telomere length, OR 1.72; 95% CI 1.07 to 2.78; ptrend=0.048). Results remained unchanged after adjustment for diabetes, body mass index and physical activity. Three SNPs at TERT (linkage disequilibrium r2<0.25) were associated with pancreatic cancer risk, including rs401681 (per minor allele OR 1.33; 95% CI 1.12 to 1.59; p=0.002), rs2736100 (per minor allele OR 1.36; 95% CI 1.13 to 1.63; p=0.001) and rs2736098 (per minor allele OR 0.75; 95% CI 0.63 to 0.90; p=0.002). The minor allele for rs401681 was associated with shorter telomere length (p=0.023). CONCLUSIONS: Prediagnostic leucocyte telomere length and genetic variants at the TERT gene region were associated with risk of pancreatic cancer.
Assuntos
Adenocarcinoma/epidemiologia , Adenocarcinoma/genética , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/genética , Telomerase/genética , Encurtamento do Telômero , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Leucócitos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Polimorfismo de Nucleotídeo Único , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Estados Unidos/epidemiologiaRESUMO
OBJECTIVE: Evidence suggests that CD274 (programmed death-ligand 1, B7-H1) immune checkpoint ligand repress antitumour immunity through its interaction with the PDCD1 (programmed cell death 1, PD-1) receptor of T lymphocytes in various tumours. We hypothesised that tumour CD274 expression levels might be inversely associated with T-cell densities in colorectal carcinoma tissue. DESIGN: We evaluated tumour CD274 expression by immunohistochemistry in 823 rectal and colon cancer cases within the Nurses' Health Study and Health Professionals Follow-up Study. We conducted multivariable ordinal logistic regression analyses to examine the association of tumour CD274 expression with CD3+, CD8+, CD45RO (PTPRC)+ or FOXP3+ cell density in tumour tissue, controlling for potential confounders including tumour status of microsatellite instability (MSI), CpG island methylator phenotype, long interspersed nucleotide element-1 methylation level and KRAS, BRAF and PIK3CA mutations. RESULTS: CD274 expression in tumour cells or stromal cells (including immune cells) was detected in 731 (89%) or 44 (5%) cases, respectively. Tumour CD274 expression level correlated inversely with FOXP3+ cell density in colorectal cancer tissue (outcome) (ptrend=0.0002). For a unit increase in outcome quartile categories, multivariable OR in the highest (vs lowest) CD274 expression score was 0.22 (95% CI 0.10 to 0.47). Tumour CD274 expression was inversely associated with MSI-high status (p=0.001). CD274 expression was not significantly associated with CD3+, CD8+ or CD45RO+ cell density, pathological lymphocytic reactions or patient survival prognosis. CONCLUSIONS: Tumour CD274 expression is inversely associated with FOXP3+ cell density in colorectal cancer tissue, suggesting a possible influence of CD274-expressing carcinoma cells on regulatory T cells in the tumour microenvironment.
Assuntos
Antígeno B7-H1/análise , Carcinoma/química , Neoplasias do Colo/química , DNA Bacteriano/análise , Linfócitos/química , Neoplasias Retais/química , Idoso , Complexo CD3/análise , Linfócitos T CD8-Positivos , Carcinoma/genética , Carcinoma/patologia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Feminino , Fatores de Transcrição Forkhead/análise , Fusobacterium nucleatum , Humanos , Antígenos Comuns de Leucócito/análise , Contagem de Linfócitos , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Receptor de Morte Celular Programada 1/análise , Neoplasias Retais/genética , Neoplasias Retais/patologia , Taxa de SobrevidaRESUMO
BACKGROUND: Colorectal carcinoma evolves through a multitude of molecular events including somatic mutations, epigenetic alterations, and aberrant protein expression, influenced by host immune reactions. One way to interrogate the complex carcinogenic process and interactions between aberrant events is to model a biomarker correlation network. Such a network analysis integrates multidimensional tumor biomarker data to identify key molecular events and pathways that are central to an underlying biological process. Due to embryological, physiological, and microbial differences, proximal and distal colorectal cancers have distinct sets of molecular pathological signatures. Given these differences, we hypothesized that a biomarker correlation network might vary by tumor location. RESULTS: We performed network analyses of 54 biomarkers, including major mutational events, microsatellite instability (MSI), epigenetic features, protein expression status, and immune reactions using data from 1380 colorectal cancer cases: 690 cases with proximal colon cancer and 690 cases with distal colorectal cancer matched by age and sex. Edges were defined by statistically significant correlations between biomarkers using Spearman correlation analyses. We found that the proximal colon cancer network formed a denser network (total number of edges, n = 173) than the distal colorectal cancer network (n = 95) (P < 0.0001 in permutation tests). The value of the average clustering coefficient was 0.50 in the proximal colon cancer network and 0.30 in the distal colorectal cancer network, indicating the greater clustering tendency of the proximal colon cancer network. In particular, MSI was a key hub, highly connected with other biomarkers in proximal colon cancer, but not in distal colorectal cancer. Among patients with non-MSI-high cancer, BRAF mutation status emerged as a distinct marker with higher connectivity in the network of proximal colon cancer, but not in distal colorectal cancer. CONCLUSION: In proximal colon cancer, tumor biomarkers tended to be correlated with each other, and MSI and BRAF mutation functioned as key molecular characteristics during the carcinogenesis. Our findings highlight the importance of considering multiple correlated pathways for therapeutic targets especially in proximal colon cancer.
Assuntos
Biomarcadores Tumorais/genética , Neoplasias do Colo , Neoplasias Colorretais , Biologia Computacional/métodos , Mapeamento de Interação de Proteínas/métodos , Neoplasias do Colo/diagnóstico , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Análise Mutacional de DNA/métodos , Feminino , Humanos , Masculino , Instabilidade de MicrossatélitesRESUMO
Although experimental evidence suggests calcium-sensing receptor (CASR) as a tumor-suppressor, the prognostic role of tumor CASR expression in colorectal carcinoma remains unclear. We hypothesized that higher tumor CASR expression might be associated with improved survival among colorectal cancer patients. We evaluated tumor expression levels of CASR by immunohistochemistry in 809 incident colorectal cancer patients within the Nurses' Health Study and the Health Professionals Follow-up Study. We used Cox proportional hazards regression models to estimate multivariable hazard ratio (HR) for the association of tumor CASR expression with colorectal cancer-specific and all-cause mortality. We adjusted for potential confounders including tumor biomarkers such as microsatellite instability, CpG island methylator phenotype, LINE-1 methylation level, expressions of PTGS2, VDR and CTNNB1 and mutations of KRAS, BRAF and PIK3CA. There were 240 colorectal cancer-specific deaths and 427 all-cause deaths. The median follow-up of censored patients was 10.8 years (interquartile range: 7.2, 15.1). Compared with patients with no or weak expression of CASR, the multivariable HRs for colorectal cancer-specific mortality were 0.80 [95% confidence interval (CI): 0.55-1.16] in patients with moderate CASR expression and 0.50 (95% CI: 0.32-0.79) in patients with intense CASR expression (p-trend = 0.003). The corresponding HRs for overall mortality were 0.85 (0.64-1.13) and 0.81 (0.58-1.12), respectively. Higher tumor CASR expression was associated with a lower risk of colorectal cancer-specific mortality. This finding needs further confirmation and if confirmed, may lead to better understanding of the role of CASR in colorectal cancer progression.
Assuntos
Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/mortalidade , Receptores de Detecção de Cálcio/metabolismo , Regulação para Cima , Idoso , Causas de Morte , Neoplasias Colorretais/genética , Metilação de DNA , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Humanos , Elementos Nucleotídeos Longos e Dispersos , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Análise de SobrevidaRESUMO
Accumulating evidence suggests that post-diagnostic insulin levels may influence colorectal cancer (CRC) survival. Yet, no previous study has examined CRC survival in relation to a post-diagnostic diet rich in foods that increase post-prandial insulin levels. We hypothesized that glycemic and insulin scores (index or load; derived from food frequency questionnaire data) may be associated with survival from specific CRC subtypes sensitive to the insulin signaling pathway. We prospectively followed 1,160 CRC patients from the Nurses' Health Study (1980-2012) and Health Professionals Follow-Up Study (1986-2012), resulting in 266 CRC deaths in 10,235 person-years. CRC subtypes were defined by seven tumor biomarkers (KRAS, BRAF, PIK3CA mutations, and IRS1, IRS2, FASN and CTNNB1 expression) implicated in the insulin signaling pathway. For overall CRC and each subtype, hazard ratio (HR) and 95% confidence interval (95% CI) for an increase of one standard deviation in each of glycemic and insulin scores were estimated using time-dependent Cox proportional hazards model. We found that insulin scores, but not glycemic scores, were positively associated with CRC mortality (HR = 1.19, 95% CI = 1.02-1.38 for index; HR = 1.23, 95% CI = 1.04-1.47 for load). The significant positive associations appeared more pronounced among PIK3CA wild-type cases and FASN-negative cases, with HR ranging from 1.36 to 1.60 across insulin scores. However, we did not observe statistically significant interactions of insulin scores with PIK3CA, FASN, or any other tumor marker (p interaction > 0.12). While additional studies are needed for definitive evidence, a high-insulinogenic diet after CRC diagnosis may contribute to worse CRC survival.
Assuntos
Biomarcadores Tumorais/metabolismo , Glicemia/metabolismo , Neoplasias Colorretais/metabolismo , Dieta , Insulina/metabolismo , Biomarcadores Tumorais/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Feminino , Seguimentos , Regulação Neoplásica da Expressão Gênica , Pessoal de Saúde/estatística & dados numéricos , Humanos , Masculino , Análise Multivariada , Mutação , Enfermeiras e Enfermeiros/estatística & dados numéricos , Modelos de Riscos Proporcionais , Estudos Prospectivos , Análise de SobrevidaRESUMO
BACKGROUND: Few studies have simultaneously assessed the prognostic value of the multiple classification systems for lymph node (LN) metastases in resected pancreatic ductal adenocarcinoma (PDAC). METHODS: In 600 patients with resected PDAC, we examined the association of LN parameters (AJCC 7th and 8th editions, LN ratio (LNR), and log odds of metastatic LN (LODDS)) with pattern of recurrence and patient survival using logistic regression and Cox proportional hazards regression, respectively. Regression models adjusted for age, sex, margin status, tumour grade, and perioperative therapy. RESULTS: Lymph node metastases classified by AJCC 7th and 8th editions, LNR, and LODDS were associated with worse disease free-survival (DFS) and overall survival (OS) (all Ptrend<0.01). American Joint Committee on Cancer 8th edition effectively predicted DFS and OS, while minimising model complexity. Lymph node metastases had weaker prognostic value in patients with positive margins and distal resections (both Pinteraction<0.03). Lymph node metastases by AJCC 7th and 8th editions did not predict the likelihood of local disease as the first site of recurrence. CONCLUSIONS: American Joint Committee on Cancer 8th edition LN classification is an effective and practical tool to predict outcomes in patients with resected PDAC. However, the prognostic value of LN metastases is attenuated in patients with positive resection margins and distal pancreatectomies.
Assuntos
Carcinoma Ductal Pancreático/secundário , Excisão de Linfonodo , Linfonodos/patologia , Recidiva Local de Neoplasia/patologia , Neoplasias Pancreáticas/patologia , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/cirurgia , Intervalo Livre de Doença , Feminino , Humanos , Linfonodos/cirurgia , Metástase Linfática , Masculino , Margens de Excisão , Pessoa de Meia-Idade , Neoplasia Residual , Pancreatectomia/métodos , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/métodos , Modelos de Riscos Proporcionais , Taxa de SobrevidaRESUMO
BACKGROUND & AIMS: Aspirin use reduces colorectal cancer risk. Aspirin, a nonsteroidal anti-inflammatory drug, inhibits prostaglandin-endoperoxide synthase 2 (PTGS2 or cyclooxygenase-2); PTGS2 promotes inflammation and suppresses T-cell-mediated adaptive immunity. We investigated whether the inverse association of aspirin use with colorectal carcinoma risk was stronger for tumors with lower degrees of lymphocytic infiltrates than for tumors with higher degrees of lymphocytic infiltrates. METHODS: We collected aspirin use data biennially from participants in the Nurses' Health Study and Health Professionals Follow-up Study. Participants were asked whether they took aspirin in most weeks, the number of tablets taken per week, and years of aspirin use. We collected available tumor specimens (n = 1458) from pathology laboratories in the United States. A pathologist confirmed the diagnosis of colorectal adenocarcinoma (excluding anal squamous cell carcinoma), and evaluated histopathology features, including patterns and degrees of lymphocytic infiltrates within and around tumor areas. Person-years of follow-up evaluation were accrued from the date of return of questionnaires until dates of colorectal cancer diagnosis, death, or the end of follow-up evaluation (June 2010). Duplication-method Cox proportional hazards regression was used to assess the association of aspirin with the incidence of colorectal carcinoma subgroups according to the degree of tumor-infiltrating lymphocytes (TILs), intratumoral periglandular reaction, peritumoral reaction, or Crohn's-like reaction. RESULTS: We documented 1458 rectal and colon cancers. The inverse association between regular aspirin use and colorectal cancer risk significantly differed by concentrations of TILs (Pheterogeneity = .007). Compared with nonregular use, regular aspirin use was associated with a lower risk of tumors that had low levels of TILs (relative risk, 0.72; 95% confidence interval, 0.63-0.81), and strength of the association depended on aspirin dose and duration (both Ptrend < .001). In contrast, aspirin use was not associated with a risk of tumors having intermediate or high levels of TILs. This differential association was consistent regardless of the status of tumor microsatellite instability, mutations in BRAF, or expression of PTGS2. Regular aspirin use was associated with a lower risk of tumors that contained low levels of CD3+ T cells, CD8+ T cells, or CD45RO (PTPRC)+ T cells (measured by immunohistochemistry and computer-assisted image analysis). CONCLUSIONS: Based on data from the prospective cohort studies, regular use of aspirin is associated with a lower risk of colorectal carcinomas with low concentrations of TILs. These findings indicate that the immune response in the tumor microenvironment could be involved in the chemopreventive effects of aspirin.
Assuntos
Adenocarcinoma/imunologia , Adenocarcinoma/prevenção & controle , Anti-Inflamatórios não Esteroides/uso terapêutico , Aspirina/uso terapêutico , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/prevenção & controle , Linfócitos do Interstício Tumoral , Adulto , Idoso , Feminino , Seguimentos , Humanos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Risco , Microambiente Tumoral/imunologiaRESUMO
OBJECTIVES: Cigarette smoking has been linked to somatic genetic and epigenetic aberrations, including CpG island methylator phenotype (CIMP)-high, microsatellite instability (MSI)-high and BRAF mutation. These molecular features have been associated with synchronous primary colorectal cancers (CRCs). Thus, we examined the hypothesis that smoking might be associated with the risk of synchronous CRCs. METHODS: Within the Health Professionals Follow-up Study and Nurses' Health Study, we examined the relationship of smoking and incidence of CRC according to tumor synchronicity, using duplication-method Cox proportional hazards regression analysis. RESULTS: We confirmed 1,981 solitary CRC and 45 synchronous CRC cases during follow-up of 134,305 individuals. CRC risk associated with smoking differed significantly by tumor synchronicity status (Pheterogeneity<0.001). When comparing current smokers with never smokers, multivariable hazard ratios (HR) were 5.27 (95% confidence interval (CI), 2.08-13.40) for synchronous CRCs and 0.97 (95% CI, 0.83-1.14) for solitary CRC. Similarly, differential associations were observed when examining cumulative pack-years smoked (Pheterogeneity=0.006). Smoking cessation for ≥10 years relative to current smoking might reduce the risk of synchronous CRCs (multivariable HR=0.42; 95% CI, 0.19-0.95), but not solitary CRC (multivariable HR=1.10; 95% CI, 0.94-1.29; Pheterogeneity=0.001). Comparing current and former smokers with never smokers, multivariable HRs for synchronous CRCs were significantly higher than those of solitary CRC positive for either CIMP-high, MSI-high, or BRAF mutation (Pheterogeneity=0.002). CONCLUSIONS: Smoking is associated with an elevated risk of synchronous CRCs. Our data support a model where smoking contributes to an etiologic field effect that favors these somatic molecular alterations and the development of multiple primary tumors.