RESUMEN
MYC's key role in oncogenesis and tumor progression has long been established for most human cancers. In melanoma, its deregulated activity by amplification of 8q24 chromosome or by upstream signaling coming from activating mutations in the RAS/RAF/MAPK pathway-the most predominantly mutated pathway in this disease-turns MYC into not only a driver but also a facilitator of melanoma progression, with documented effects leading to an aggressive clinical course and resistance to targeted therapy. Here, by making use of Omomyc, the most characterized MYC inhibitor to date that has just successfully completed a phase I clinical trial, we show for the first time that MYC inhibition in melanoma induces remarkable transcriptional modulation, resulting in severely compromised tumor growth and a clear abrogation of metastatic capacity independently of the driver mutation. By reducing MYC's transcriptional footprint in melanoma, Omomyc elicits gene expression profiles remarkably similar to those of patients with good prognosis, underlining the therapeutic potential that such an approach could eventually have in the clinic in this dismal disease.
Asunto(s)
Melanoma , Humanos , Pronóstico , Melanoma/genética , Transducción de Señal , Carcinogénesis , Transformación Celular Neoplásica , Proteínas Proto-Oncogénicas c-myc/metabolismoRESUMEN
BACKGROUND: Eribulin is a microtubule-targeting agent approved for the treatment of advanced or metastatic breast cancer (BC) previously treated with anthracycline- and taxane-based regimens. PIK3CA mutation is associated with worse response to chemotherapy in oestrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2-) metastatic BC. We aimed to evaluate the role of phosphoinositide 3-kinase (PI3K)/AKT pathway mutations in eribulin resistance. METHODS: Resistance to eribulin was evaluated in HER2- BC cell lines and patient-derived tumour xenografts, and correlated with a mutation in the PI3K/AKT pathway. RESULTS: Eleven out of 23 HER2- BC xenografts treated with eribulin exhibited disease progression. No correlation with ER status was detected. Among the resistant models, 64% carried mutations in PIK3CA, PIK3R1 or AKT1, but only 17% among the sensitive xenografts (P = 0.036). We observed that eribulin treatment induced AKT phosphorylation in vitro and in patient tumours. In agreement, the addition of PI3K inhibitors reversed primary and acquired resistance to eribulin in xenograft models, regardless of the genetic alterations in PI3K/AKT pathway or ER status. Mechanistically, PI3K blockade reduced p21 levels likely enabling apoptosis, thus sensitising to eribulin treatment. CONCLUSIONS: PI3K pathway activation induces primary resistance or early adaptation to eribulin, supporting the combination of PI3K inhibitors and eribulin for the treatment of HER2- BC patients.
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Neoplasias de la Mama/tratamiento farmacológico , Fosfatidilinositol 3-Quinasa Clase I/metabolismo , Resistencia a Antineoplásicos , Furanos/farmacología , Cetonas/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Receptor ErbB-2/metabolismo , Animales , Apoptosis , Biomarcadores de Tumor/metabolismo , Neoplasias de la Mama/patología , Ciclo Celular , Proliferación Celular , Fosfatidilinositol 3-Quinasa Clase I/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Fosforilación , Proteínas Proto-Oncogénicas c-akt/genética , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Exposure to ultraviolet (UV) radiation from sunlight accounts for 90% of the symptoms of premature skin aging and skin cancer. The tumor suppressor serine-threonine kinase LKB1 is mutated in Peutz-Jeghers syndrome and in a spectrum of epithelial cancers whose etiology suggests a cooperation with environmental insults. Here we analyzed the role of LKB1 in a UV-dependent mouse skin cancer model and show that LKB1 haploinsufficiency is enough to impede UVB-induced DNA damage repair, contributing to tumor development driven by aberrant growth factor signaling. We demonstrate that LKB1 and its downstream kinase NUAK1 bind to CDKN1A. In response to UVB irradiation, LKB1 together with NUAK1 phosphorylates CDKN1A regulating the DNA damage response. Upon UVB treatment, LKB1 or NUAK1 deficiency results in CDKN1A accumulation, impaired DNA repair and resistance to apoptosis. Importantly, analysis of human tumor samples suggests that LKB1 mutational status could be a prognostic risk factor for UV-induced skin cancer. Altogether, our results identify LKB1 as a DNA damage sensor protein regulating skin UV-induced DNA damage response.
Asunto(s)
Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Daño del ADN/efectos de la radiación , Proteínas Serina-Treonina Quinasas/metabolismo , Rayos Ultravioleta/efectos adversos , Proteínas Quinasas Activadas por AMP , Animales , Animales Recién Nacidos , Apoptosis/genética , Apoptosis/efectos de la radiación , Células Cultivadas , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Modelos Animales de Enfermedad , Factor de Crecimiento de Hepatocito/genética , Humanos , Queratinocitos/metabolismo , Queratinocitos/patología , Queratinocitos/efectos de la radiación , Ratones Transgénicos , Neoplasias de Células Escamosas/etiología , Neoplasias de Células Escamosas/patología , Fosforilación , Proteínas Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Represoras/metabolismo , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patologíaRESUMEN
PURPOSE: FGFR1 amplification (FGFR1amp) is recurrent in metastatic breast cancer (MBC) and is associated with resistance to endocrine therapy and CDK4/6 inhibitors (CDK4/6is). Multi-tyrosine kinase inhibitors (MTKIs) and selective pan-FGFR inhibitors (FGFRis) are being developed for FGFR1amp breast cancer. High-level FGFR amplification and protein expression by IHC have identified breast cancer responders to FGFRis or MTKIs, respectively. EXPERIMENTAL DESIGN: Here, we used preclinical models and patient samples to identify predictive biomarkers to these drugs. We evaluated the antitumor activity of an FGFRi and an MTKI in a collection of 17 breast cancer patient-derived xenografts (PDXs) harboring amplification in FGFR1/2/3/4 and in 10 patients receiving either an FGFRi/MTKI. mRNA levels were measured on FFPE tumor samples using two commercial strategies. Proliferation and angiogenesis were evaluated by detecting Ki-67 and CD31 in viable areas by immunofluorescence. RESULTS: High FGFR1-4 mRNA levels but not copy-number alteration (CNA) is associated with FGFRi response. Treatment with MTKIs showed higher response rates than with FGFRis (86% vs. 53%), regardless of the FGFR1-4 mRNA levels. FGFR-addicted PDXs exhibited an antiproliferative response to either FGFRis or MTKIs, and PDXs exclusively sensitive to MTKI exhibited an additional antiangiogenic response. Consistently, the clinical benefit of MTKIs was not associated with high FGFR1-4 mRNA levels and was observed in patients previously treated with antiangiogenic drugs. CONCLUSIONS: Tailored therapy with FGFRis in molecularly selected MBC based on high FGFR1-4 mRNA levels warrants prospective validation in patients with CDK4/6i-resistant luminal breast cancer and in patients with TNBC without targeted therapeutic options.
Asunto(s)
Neoplasias de la Mama , ARN Mensajero , Proteínas Tirosina Quinasas Receptoras , Femenino , Humanos , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , ARN Mensajero/biosíntesis , ARN Mensajero/genética , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Transducción de SeñalRESUMEN
PARP inhibitors (PARPi) are approved drugs for platinum-sensitive, high-grade serous ovarian cancer (HGSOC) and for breast, prostate, and pancreatic cancers (PaC) harboring genetic alterations impairing homologous recombination repair (HRR). Detection of nuclear RAD51 foci in tumor cells is a marker of HRR functionality, and we previously established a test to detect RAD51 nuclear foci. Here, we aimed to validate the RAD51 score cut off and compare the performance of this test to other HRR deficiency (HRD) detection methods. Laboratory models from BRCA1/BRCA2-associated breast cancer, HGSOC, and PaC were developed and evaluated for their response to PARPi and cisplatin. HRD in these models and patient samples was evaluated by DNA sequencing of HRR genes, genomic HRD tests, and RAD51 foci detection. We established patient-derived xenograft models from breast cancer (n = 103), HGSOC (n = 4), and PaC (n = 2) that recapitulated patient HRD status and treatment response. The RAD51 test showed higher accuracy than HRR gene mutations and genomic HRD analysis for predicting PARPi response (95%, 67%, and 71%, respectively). RAD51 detection captured dynamic changes in HRR status upon acquisition of PARPi resistance. The accuracy of the RAD51 test was similar to HRR gene mutations for predicting platinum response. The predefined RAD51 score cut off was validated, and the high predictive value of the RAD51 test in preclinical models was confirmed. These results collectively support pursuing clinical assessment of the RAD51 test in patient samples from randomized trials testing PARPi or platinum-based therapies. SIGNIFICANCE: This work demonstrates the high accuracy of a histopathology-based test based on the detection of RAD51 nuclear foci in predicting response to PARPi and cisplatin.
Asunto(s)
Neoplasias de la Mama , Neoplasias Ováricas , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Carcinoma Epitelial de Ovario/genética , Cisplatino/farmacología , Cisplatino/uso terapéutico , Femenino , Recombinación Homóloga/genética , Humanos , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Recombinasa Rad51/genéticaRESUMEN
CDK4/6 inhibitors combined with endocrine therapy have demonstrated higher antitumor activity than endocrine therapy alone for the treatment of advanced estrogen receptor-positive breast cancer. Some of these tumors are de novo resistant to CDK4/6 inhibitors and others develop acquired resistance. Here, we show that p16 overexpression is associated with reduced antitumor activity of CDK4/6 inhibitors in patient-derived xenografts (n = 37) and estrogen receptor-positive breast cancer cell lines, as well as reduced response of early and advanced breast cancer patients to CDK4/6 inhibitors (n = 89). We also identified heterozygous RB1 loss as biomarker of acquired resistance and poor clinical outcome. Combination of the CDK4/6 inhibitor ribociclib with the PI3K inhibitor alpelisib showed antitumor activity in estrogen receptor-positive non-basal-like breast cancer patient-derived xenografts, independently of PIK3CA, ESR1 or RB1 mutation, also in drug de-escalation experiments or omitting endocrine therapy. Our results offer insights into predicting primary/acquired resistance to CDK4/6 inhibitors and post-progression therapeutic strategies.
Asunto(s)
Antineoplásicos , Neoplasias de la Mama , Inhibidores de Proteínas Quinasas , Antineoplásicos/uso terapéutico , Biomarcadores , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Resistencia a Antineoplásicos/genética , Femenino , Humanos , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/uso terapéutico , Receptores de Estrógenos/metabolismo , Proteínas de Unión a Retinoblastoma/genética , Proteínas de Unión a Retinoblastoma/metabolismo , Ubiquitina-Proteína Ligasas/metabolismoRESUMEN
PURPOSE: PARP inhibitors (PARPi) induce synthetic lethality in homologous recombination repair (HRR)-deficient tumors and are used to treat breast, ovarian, pancreatic, and prostate cancers. Multiple PARPi resistance mechanisms exist, most resulting in restoration of HRR and protection of stalled replication forks. ATR inhibition was highlighted as a unique approach to reverse both aspects of resistance. Recently, however, a PARPi/WEE1 inhibitor (WEE1i) combination demonstrated enhanced antitumor activity associated with the induction of replication stress, suggesting another approach to tackling PARPi resistance. EXPERIMENTAL DESIGN: We analyzed breast and ovarian patient-derived xenoimplant models resistant to PARPi to quantify WEE1i and ATR inhibitor (ATRi) responses as single agents and in combination with PARPi. Biomarker analysis was conducted at the genetic and protein level. Metabolite analysis by mass spectrometry and nucleoside rescue experiments ex vivo were also conducted in patient-derived models. RESULTS: Although WEE1i response was linked to markers of replication stress, including STK11/RB1 and phospho-RPA, ATRi response associated with ATM mutation. When combined with olaparib, WEE1i could be differentiated from the ATRi/olaparib combination, providing distinct therapeutic strategies to overcome PARPi resistance by targeting the replication stress response. Mechanistically, WEE1i sensitivity was associated with shortage of the dNTP pool and a concomitant increase in replication stress. CONCLUSIONS: Targeting the replication stress response is a valid therapeutic option to overcome PARPi resistance including tumors without an underlying HRR deficiency. These preclinical insights are now being tested in several clinical trials where the PARPi is administered with either the WEE1i or the ATRi.
Asunto(s)
Antineoplásicos , Neoplasias Ováricas , Antineoplásicos/uso terapéutico , Proteínas de la Ataxia Telangiectasia Mutada , Proteína BRCA1/genética , Biomarcadores , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Femenino , Humanos , Nucleósidos/uso terapéutico , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Neoplasias Ováricas/patología , Ftalazinas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Tirosina Quinasas/genética , Proteínas Tirosina Quinasas/metabolismoRESUMEN
Melanoma is the most lethal human skin cancer. If metastatic, it becomes very aggressive and resistant to standard modalities of anticancer treatment. During the last 10 years, several therapeutic strategies have been tested including the use of single and combined small drugs. Experimental results indicate that RAS and PI3K pathways are important for the development and maintenance of melanoma. In this study, we assessed the in vitro and in vivo inhibition potential of PI-103, a PI3K (p110alpha)/mTOR inhibitor and sorafenib, a BRAF inhibitor, as single agents and in combination in primary melanoma cell lines. Although PI-103 and sorafenib inhibited melanoma in vitro cell proliferation and viability, the inhibition of RAS pathway appeared to be more effective. The combination of the two agents in in vitro showed a synergistic effect inhibiting RAS and PI3K pathways in a cell line dependent manner. However, no cooperative effect was observed in blocking in vivo tumor growth in immunocompetent mice. In contrary to the expected, the data indicate that PI-103 induced immunosuppression promoting in vivo tumor growth and inhibiting apoptosis. Furthermore, in vitro studies examining the effects of the PI3K/mTOR inhibitor in tumor derived cell lines indicated that PI-103 induced the anti-apoptotic BH3 family proteins Mcl1, Bcl2 and Bcl(xL) favoring, the in vitro survival of sorafenib treated melanoma cells. These data certainly makes an argument for investigating unexpected effects of rational drug combinations on immunocompetent animal models prior to conducting clinical studies.
Asunto(s)
Bencenosulfonatos/farmacología , Furanos/farmacología , Terapia de Inmunosupresión , Péptidos y Proteínas de Señalización Intracelular/antagonistas & inhibidores , Melanoma/patología , Inhibidores de las Quinasa Fosfoinosítidos-3 , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Piridinas/farmacología , Pirimidinas/farmacología , Animales , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptosis/efectos de los fármacos , Western Blotting , Proliferación Celular , Ensayo de Unidades Formadoras de Colonias , Quinasas MAP Reguladas por Señal Extracelular/genética , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Técnica del Anticuerpo Fluorescente , Humanos , Técnicas para Inmunoenzimas , Péptidos y Proteínas de Señalización Intercelular/farmacología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Masculino , Melanoma/inmunología , Melanoma/mortalidad , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Niacinamida/análogos & derivados , Compuestos de Fenilurea , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sorafenib , Tasa de Supervivencia , Serina-Treonina Quinasas TOR , Células Tumorales Cultivadas , Proteínas ras/genética , Proteínas ras/metabolismoRESUMEN
BACKGROUND: Melanoma is the most deadly form of skin cancer without effective treatment. Methylthioadenosine (MTA) is a naturally occurring nucleoside with differential effects on normal and transformed cells. MTA has been widely demonstrated to promote anti-proliferative and pro-apoptotic responses in different cell types. In this study we have assessed the therapeutic potential of MTA in melanoma treatment. METHODS: To investigate the therapeutic potential of MTA we performed in vitro proliferation and viability assays using six different mouse and human melanoma cell lines wild type for RAS and BRAF or harboring different mutations in RAS pathway. We also have tested its therapeutic capabilities in vivo in a xenograft mouse melanoma model and using variety of molecular techniques and tissue culture we investigated its anti-proliferative and pro-apoptotic properties. RESULTS: In vitro experiments showed that MTA treatment inhibited melanoma cell proliferation and viability in a dose dependent manner, where BRAF mutant melanoma cell lines appear to be more sensitive. Importantly, MTA was effective inhibiting in vivo tumor growth. The molecular analysis of tumor samples and in vitro experiments indicated that MTA induces cytostatic rather than pro-apoptotic effects inhibiting the phosphorylation of Akt and S6 ribosomal protein and inducing the down-regulation of cyclin D1. CONCLUSIONS: MTA inhibits melanoma cell proliferation and in vivo tumor growth particularly in BRAF mutant melanoma cells. These data reveal a naturally occurring drug potentially useful for melanoma treatment.
Asunto(s)
Adenosina/farmacología , Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Melanoma/tratamiento farmacológico , Neoplasias Cutáneas/tratamiento farmacológico , Tionucleósidos/farmacología , Adenosina/análogos & derivados , Animales , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Ciclina D1/metabolismo , Relación Dosis-Respuesta a Droga , Genes ras , Humanos , Masculino , Melanoma/genética , Melanoma/patología , Ratones , Mutación , Fosforilación , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteína S6 Ribosómica/metabolismo , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/patología , Factores de Tiempo , Carga Tumoral , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Elucidating the contribution of somatic mutations to cancer is essential for personalized medicine. STK11 (LKB1) appears to be inactivated in human cancer. However, somatic missense mutations also occur, and the role/s of these alterations to this disease remain unknown. Here, we investigated the contribution of four missense LKB1 somatic mutations in tumor biology. Three out of the four mutants lost their tumor suppressor capabilities and showed deficient kinase activity. The remaining mutant retained the enzymatic activity of wild type LKB1, but induced increased cell motility. Mechanistically, LKB1 mutants resulted in differential gene expression of genes encoding vesicle trafficking regulating molecules, adhesion molecules and cytokines. The differentially regulated genes correlated with protein networks identified through comparative secretome analysis. Notably, three mutant isoforms promoted tumor growth, and one induced inflammation-like features together with dysregulated levels of cytokines. These findings uncover oncogenic roles of LKB1 somatic mutations, and will aid in further understanding their contributions to cancer development and progression.
Asunto(s)
Biomarcadores de Tumor/genética , Movimiento Celular , Inflamación/patología , Neoplasias Pulmonares/patología , Melanoma/patología , Mutación Missense , Proteínas Serina-Treonina Quinasas/genética , Quinasas de la Proteína-Quinasa Activada por el AMP , Animales , Apoptosis , Biomarcadores de Tumor/metabolismo , Ciclo Celular , Proliferación Celular , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Inflamación/genética , Inflamación/inmunología , Inflamación/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/metabolismo , Melanoma/genética , Melanoma/inmunología , Melanoma/metabolismo , Ratones , Ratones Desnudos , Fosforilación , Isoformas de Proteínas , Proteínas Serina-Treonina Quinasas/metabolismo , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
PURPOSE: AZD5363/capivasertib is a pan-AKT catalytic inhibitor with promising activity in combination with paclitaxel in triple-negative metastatic breast cancer harboring PI3K/AKT-pathway alterations and in estrogen receptor-positive breast cancer in combination with fulvestrant. Here, we aimed to identify response biomarkers and uncover mechanisms of resistance to AZD5363 and its combination with paclitaxel. EXPERIMENTAL DESIGN: Genetic and proteomic markers were analyzed in 28 HER2-negative patient-derived xenografts (PDXs) and in patient samples, and correlated to AZD5363 sensitivity as single agent and in combination with paclitaxel. RESULTS: Four PDX were derived from patients receiving AZD5363 in the clinic which exhibited concordant treatment response. Mutations in PIK3CA/AKT1 and absence of mTOR complex 1 (mTORC1)-activating alterations, for example, in MTOR or TSC1, were associated with sensitivity to AZD5363 monotherapy. Interestingly, excluding PTEN from the composite biomarker increased its accuracy from 64% to 89%. Moreover, resistant PDXs exhibited low baseline pAKT S473 and residual pS6 S235 upon treatment, suggesting that parallel pathways bypass AKT/S6K1 signaling in these models. We identified two mechanisms of acquired resistance to AZD5363: cyclin D1 overexpression and loss of AKT1 p.E17K. CONCLUSIONS: This study provides insight into putative predictive biomarkers of response and acquired resistance to AZD5363 in HER2-negative metastatic breast cancer.
Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Biomarcadores de Tumor/genética , Neoplasias de la Mama/terapia , Resistencia a Antineoplásicos/genética , Inhibidores de Proteínas Quinasas/farmacología , Animales , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Mama/patología , Mama/cirugía , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Quimioterapia Adyuvante/métodos , Fosfatidilinositol 3-Quinasa Clase I/genética , Análisis Mutacional de ADN , Femenino , Humanos , Mastectomía , Ratones , Mutación , Paclitaxel/farmacología , Paclitaxel/uso terapéutico , Pronóstico , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas c-akt/genética , Pirimidinas/farmacología , Pirimidinas/uso terapéutico , Pirroles/farmacología , Pirroles/uso terapéutico , Proteínas Quinasas S6 Ribosómicas 70-kDa/metabolismo , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/genética , Proteína 1 del Complejo de la Esclerosis Tuberosa/genética , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Poly(ADP-ribose) polymerase (PARP) inhibitors (PARPi) are effective in cancers with defective homologous recombination DNA repair (HRR), including BRCA1/2-related cancers. A test to identify additional HRR-deficient tumors will help to extend their use in new indications. We evaluated the activity of the PARPi olaparib in patient-derived tumor xenografts (PDXs) from breast cancer (BC) patients and investigated mechanisms of sensitivity through exome sequencing, BRCA1 promoter methylation analysis, and immunostaining of HRR proteins, including RAD51 nuclear foci. In an independent BC PDX panel, the predictive capacity of the RAD51 score and the homologous recombination deficiency (HRD) score were compared. To examine the clinical feasibility of the RAD51 assay, we scored archival breast tumor samples, including PALB2-related hereditary cancers. The RAD51 score was highly discriminative of PARPi sensitivity versus PARPi resistance in BC PDXs and outperformed the genomic test. In clinical samples, all PALB2-related tumors were classified as HRR-deficient by the RAD51 score. The functional biomarker RAD51 enables the identification of PARPi-sensitive BC and broadens the population who may benefit from this therapy beyond BRCA1/2-related cancers.
Asunto(s)
Antineoplásicos/administración & dosificación , Neoplasias de la Mama/diagnóstico , Resistencia a Antineoplásicos , Xenoinjertos/patología , Ftalazinas/administración & dosificación , Piperazinas/administración & dosificación , Inhibidores de Poli(ADP-Ribosa) Polimerasas/administración & dosificación , Recombinasa Rad51/análisis , Animales , Biomarcadores de Tumor/análisis , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Femenino , Recombinación Homóloga , Humanos , RatonesRESUMEN
The Snail gene product is a transcriptional repressor of E-cadherin expression and an inducer of the epithelial-to-mesenchymal transition in several epithelial tumor cell lines. This report presents data indicating that Snail function is controlled by its intracellular location. The cytosolic distribution of Snail depended on export from the nucleus by a CRM1-dependent mechanism, and a nuclear export sequence (NES) was located in the regulatory domain of this protein. Export of Snail was controlled by phosphorylation of a Ser-rich sequence adjacent to this NES. Modification of this sequence released the restriction created by the zinc finger domain and allowed nuclear export of the protein. The phosphorylation and subcellular distribution of Snail are controlled by cell attachment to the extracellular matrix. Suspended cells presented higher levels of phosphorylated Snail and an augmented extranuclear localization with respect to cells attached to the plate. These findings show the existence in tumor cells of an effective and fine-tuning nontranscriptional mechanism of regulation of Snail activity dependent on the extracellular environment.
Asunto(s)
Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Receptores Citoplasmáticos y Nucleares , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transporte Activo de Núcleo Celular/fisiología , Animales , Secuencia de Bases , Núcleo Celular/genética , Núcleo Celular/metabolismo , Citosol/metabolismo , Matriz Extracelular/metabolismo , Humanos , Carioferinas/metabolismo , Leucina/metabolismo , Ratones , Datos de Secuencia Molecular , Señales de Localización Nuclear/genética , Señales de Localización Nuclear/metabolismo , Fosforilación , Estructura Terciaria de Proteína , Transporte de Proteínas/fisiología , Serina/metabolismo , Factores de Transcripción de la Familia Snail , Fracciones Subcelulares , Células Tumorales Cultivadas , Proteína Exportina 1RESUMEN
Small-molecule inhibitors of the CDK4/6 cell-cycle kinases have shown clinical efficacy in estrogen receptor (ER)-positive metastatic breast cancer, although their cytostatic effects are limited by primary and acquired resistance. Here we report that ER-positive breast cancer cells can adapt quickly to CDK4/6 inhibition and evade cytostasis, in part, via noncanonical cyclin D1-CDK2-mediated S-phase entry. This adaptation was prevented by cotreatment with hormone therapies or PI3K inhibitors, which reduced the levels of cyclin D1 (CCND1) and other G1-S cyclins, abolished pRb phosphorylation, and inhibited activation of S-phase transcriptional programs. Combined targeting of both CDK4/6 and PI3K triggered cancer cell apoptosis in vitro and in patient-derived tumor xenograft (PDX) models, resulting in tumor regression and improved disease control. Furthermore, a triple combination of endocrine therapy, CDK4/6, and PI3K inhibition was more effective than paired combinations, provoking rapid tumor regressions in a PDX model. Mechanistic investigations showed that acquired resistance to CDK4/6 inhibition resulted from bypass of cyclin D1-CDK4/6 dependency through selection of CCNE1 amplification or RB1 loss. Notably, although PI3K inhibitors could prevent resistance to CDK4/6 inhibitors, they failed to resensitize cells once resistance had been acquired. However, we found that cells acquiring resistance to CDK4/6 inhibitors due to CCNE1 amplification could be resensitized by targeting CDK2. Overall, our results illustrate convergent mechanisms of early adaptation and acquired resistance to CDK4/6 inhibitors that enable alternate means of S-phase entry, highlighting strategies to prevent the acquisition of therapeutic resistance to these agents. Cancer Res; 76(8); 2301-13. ©2016 AACR.
Asunto(s)
Neoplasias de la Mama/enzimología , Quinasa 4 Dependiente de la Ciclina/antagonistas & inhibidores , Quinasa 6 Dependiente de la Ciclina/antagonistas & inhibidores , Receptores de Estrógenos/metabolismo , Animales , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Línea Celular Tumoral , Resistencia a Antineoplásicos , Femenino , Xenoinjertos , Humanos , Ratones , Piperazinas/uso terapéutico , Piridinas/uso terapéuticoRESUMEN
BACKGROUND: Cancer patients often show no or only modest benefit from a given therapy. This major problem in oncology is generally attributed to the lack of specific predictive biomarkers, yet a global measure of cancer cell activity may support a comprehensive mechanistic understanding of therapy efficacy. We reasoned that network analysis of omic data could help to achieve this goal. METHODS: A measure of "cancer network activity" (CNA) was implemented based on a previously defined network feature of communicability. The network nodes and edges corresponded to human proteins and experimentally identified interactions, respectively. The edges were weighted proportionally to the expression of the genes encoding for the corresponding proteins and relative to the number of direct interactors. The gene expression data corresponded to the basal conditions of 595 human cancer cell lines. Therapeutic responses corresponded to the impairment of cell viability measured by the half maximal inhibitory concentration (IC50) of 130 drugs approved or under clinical development. Gene ontology, signaling pathway, and transcription factor-binding annotations were taken from public repositories. Predicted synergies were assessed by determining the viability of four breast cancer cell lines and by applying two different analytical methods. RESULTS: The effects of drug classes were associated with CNAs formed by different cell lines. CNAs also differentiate target families and effector pathways. Proteins that occupy a central position in the network largely contribute to CNA. Known key cancer-associated biological processes, signaling pathways, and master regulators also contribute to CNA. Moreover, the major cancer drivers frequently mediate CNA and therapeutic differences. Cell-based assays centered on these differences and using uncorrelated drug effects reveals novel synergistic combinations for the treatment of breast cancer dependent on PI3K-mTOR signaling. CONCLUSIONS: Cancer therapeutic responses can be predicted on the basis of a systems-level analysis of molecular interactions and gene expression. Fundamental cancer processes, pathways, and drivers contribute to this feature, which can also be exploited to predict precise synergistic drug combinations.
Asunto(s)
Antineoplásicos/farmacología , Drogas en Investigación/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Redes Reguladoras de Genes/efectos de los fármacos , Proteínas de Neoplasias/genética , Medicamentos bajo Prescripción/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Sinergismo Farmacológico , Femenino , Perfilación de la Expresión Génica , Ontología de Genes , Humanos , Anotación de Secuencia Molecular , Mutación , Proteínas de Neoplasias/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Transducción de Señal , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismoRESUMEN
Activating mutations of PIK3CA are the most frequent genomic alterations in estrogen receptor (ER)-positive breast tumors, and selective phosphatidylinositol 3-kinase α (PI3Kα) inhibitors are in clinical development. The activity of these agents, however, is not homogeneous, and only a fraction of patients bearing PIK3CA-mutant ER-positive tumors benefit from single-agent administration. Searching for mechanisms of resistance, we observed that suppression of PI3K signaling results in induction of ER-dependent transcriptional activity, as demonstrated by changes in expression of genes containing ER-binding sites and increased occupancy by the ER of promoter regions of up-regulated genes. Furthermore, expression of ESR1 mRNA and ER protein were also increased upon PI3K inhibition. These changes in gene expression were confirmed in vivo in xenografts and patient-derived models and in tumors from patients undergoing treatment with the PI3Kα inhibitor BYL719. The observed effects on transcription were enhanced by the addition of estradiol and suppressed by the anti-ER therapies fulvestrant and tamoxifen. Fulvestrant markedly sensitized ER-positive tumors to PI3Kα inhibition, resulting in major tumor regressions in vivo. We propose that increased ER transcriptional activity may be a reactive mechanism that limits the activity of PI3K inhibitors and that combined PI3K and ER inhibition is a rational approach to target these tumors.
Asunto(s)
Neoplasias de la Mama/metabolismo , Receptor alfa de Estrógeno/metabolismo , Mutación , Fosfatidilinositol 3-Quinasas/metabolismo , Animales , Antineoplásicos/química , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Línea Celular Tumoral , Resistencia a Antineoplásicos , Retículo Endoplásmico/metabolismo , Femenino , Humanos , Células MCF-7 , Ratones , Ratones Desnudos , Metástasis de la Neoplasia , Trasplante de Neoplasias , Análisis de Secuencia por Matrices de Oligonucleótidos , Inhibidores de las Quinasa Fosfoinosítidos-3 , Proyectos de Investigación , Transducción de Señal , Tiazoles/farmacologíaRESUMEN
PURPOSE: PI3K pathway activation occurs in concomitance with RAS/BRAF mutations in colorectal cancer, limiting the sensitivity to targeted therapies. Several clinical studies are being conducted to test the tolerability and clinical activity of dual MEK and PI3K pathway blockade in solid tumors. EXPERIMENTAL DESIGN: In the present study, we explored the efficacy of dual pathway blockade in colorectal cancer preclinical models harboring concomitant activation of the ERK and PI3K pathways. Moreover, we investigated if TP53 mutation affects the response to this therapy. RESULTS: Dual MEK and mTORC1/2 blockade resulted in synergistic antiproliferative effects in cell lines bearing alterations in KRAS/BRAF and PIK3CA/PTEN. Although the on-treatment cell-cycle effects were not affected by the TP53 status, a marked proapoptotic response to therapy was observed exclusively in wild-type TP53 colorectal cancer models. We further interrogated two independent panels of KRAS/BRAF- and PIK3CA/PTEN-altered cell line- and patient-derived tumor xenografts for the antitumor response toward this combination of agents. A combination response that resulted in substantial antitumor activity was exclusively observed among the wild-type TP53 models (two out of five, 40%), but there was no such response across the eight mutant TP53 models (0%). Interestingly, within a cohort of 14 patients with colorectal cancer treated with these agents for their metastatic disease, two patients with long-lasting responses (32 weeks) had TP53 wild-type tumors. CONCLUSIONS: Our data support that, in wild-type TP53 colorectal cancer cells with ERK and PI3K pathway alterations, MEK blockade results in potent p21 induction, preventing apoptosis to occur. In turn, mTORC1/2 inhibition blocks MEK inhibitor-mediated p21 induction, unleashing apoptosis. Clin Cancer Res; 21(24); 5499-510. ©2015 AACR.
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Antineoplásicos/farmacología , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Mutación , Inhibidores de Proteínas Quinasas/farmacología , Proteína p53 Supresora de Tumor/genética , Animales , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/patología , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Modelos Animales de Enfermedad , Sinergismo Farmacológico , Quinasas MAP Reguladas por Señal Extracelular/antagonistas & inhibidores , Femenino , Humanos , Diana Mecanicista del Complejo 1 de la Rapamicina , Diana Mecanicista del Complejo 2 de la Rapamicina , Ratones , Complejos Multiproteicos/antagonistas & inhibidores , Inhibidores de las Quinasa Fosfoinosítidos-3 , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Proteína p53 Supresora de Tumor/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Proteína X Asociada a bcl-2/metabolismoRESUMEN
UNLABELLED: Genomic characterization of recurrent breast and lung tumors developed over the course of 10 years in a 29-year-old patient with a germline TP53 mutation (Li-Fraumeni Syndrome) identified oncogenic alterations in the HER2 and EGFR genes across all tumors, including HER2 amplifications, an EGFR-exon 20 insertion, and the first-in-humans HER2V659E mutation showing a phenotypic convergent evolution toward HER2 and EGFR alterations. Following the identification of HER2-activating events in the most recent lung carcinoma and in circulating tumor cells, we treated the reminiscent metastatic lesions with a lapatinib-based therapy. A symptomatic and radiologic clinical response was achieved. HER2V659E sensitivity to lapatinib was confirmed in the laboratory. SIGNIFICANCE: The precise knowledge of the genomic alterations present in tumors is critical to selecting the optimal treatment for each patient. Here, we report the molecular characterization and clinical response to a lapatinib-based therapy for the tumors of a Li-Fraumeni patient showing prevalence of HER2 and EGFR genomic alterations.
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Síndrome de Li-Fraumeni/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Quinazolinas/uso terapéutico , Receptor ErbB-2/genética , Adulto , Exoma , Femenino , Humanos , Lapatinib , Síndrome de Li-Fraumeni/genética , Síndrome de Li-Fraumeni/metabolismo , Síndrome de Li-Fraumeni/patología , Mutación , Metástasis de la Neoplasia , Receptor ErbB-2/metabolismo , Transducción de Señal/efectos de los fármacos , Células Tumorales CultivadasRESUMEN
PURPOSE: The PI3K/Akt/mTOR pathway is an attractive target in HER2-positive breast cancer that is refractory to anti-HER2 therapy. The hypothesis is that the suppression of this pathway results in sensitization to anti-HER2 agents. However, this combinatorial strategy has not been comprehensively tested in models of trastuzumab and lapatinib resistance. EXPERIMENTAL DESIGN: We analyzed in vitro cell viability and induction of apoptosis in five different cell lines resistant to trastuzumab and lapatinib. Inhibition of HER2/HER3 phosphorylation, PI3K/Akt/mTOR, and extracellular signal-regulated kinase (ERK) signaling pathways was evaluated by Western blotting. Tumor growth inhibition after treatment with lapatinib, INK-128, or the combination of both agents was evaluated in three different animal models: two cell-based xenograft models refractory to both trastuzumab and lapatinib and a xenograft derived from a patient who relapsed on trastuzumab-based therapy. RESULTS: The addition of lapatinib to INK-128 prevented both HER2 and HER3 phosphorylation induced by INK-128, resulting in inhibition of both PI3K/Akt/mTOR and ERK pathways. This dual blockade produced synergistic induction of cell death in five different HER2-positive cell lines resistant to trastuzumab and lapatinib. In vivo, both cell line-based and patient-derived xenografts showed exquisite sensitivity to the antitumor activity of the combination of lapatinib and INK-128, which resulted in durable tumor shrinkage and exhibited no signs of toxicity in these models. CONCLUSIONS: The simultaneous blockade of both PI3K/Akt/mTOR and ERK pathways obtained by combining lapatinib with INK-128 acts synergistically in inducing cell death and tumor regression in breast cancer models refractory to anti-HER2 therapy.