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Aim: A systematic review and meta-analysis were performed to evaluate the efficacy of treatments for previously treated advanced biliary tract cancer (BTC) patients. Materials & methods: Databases were searched for studies evaluating treatments for advanced (unresectable and/or metastatic) BTC patients who progressed on prior therapy. Pooled estimates of objective response rate (ORR), median overall survival (OS) and median progression-free survival (PFS) were calculated using random effects meta-analysis. Results: Across 31 studies evaluating chemotherapy or targeted treatment regimens in an unselected advanced BTC patient population, pooled ORR was 6.9%, median OS was 6.6 months and median PFS was 3.2 months. Conclusion: The efficacy of conventional treatments for previously treated advanced BTC patients is poor and could be improved by novel therapies.
What is this article about? Most patients with biliary tract cancer are identified with advanced disease, and almost all go through a worsening of the disease after their first treatment. For patients who go on to receive their next treatment, current guidelines are unclear regarding the best treatment choice. Therefore, we examined the available medical literature and performed an analysis of multiple studies to calculate overall estimates of the clinical value of standard treatments for these patients. Our goal was to develop a benchmark against which to compare the clinical value of new treatments that are currently being assessed in clinical trials. What were the results? We identified 31 studies assessing standard treatments (involving chemotherapy or molecularly targeted treatments) in previously treated advanced biliary tract cancer patients. Across these studies, the objective tumor response rate was 6.9%, median overall survival was 6.6 months and median progression-free survival was 3.2 months. What do the results of the study mean? These results indicate that there is limited clinical value of standard treatments for patients with advanced biliary tract cancer whose disease worsened after first treatment. This medical need could potentially be met by new treatments, such as immunotherapies that restore the immune system's ability to attack cancer cells and thereby prolong patient survival.
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Neoplasias del Sistema Biliar , Humanos , Neoplasias del Sistema Biliar/tratamiento farmacológico , Neoplasias del Sistema Biliar/mortalidad , Neoplasias del Sistema Biliar/patología , Neoplasias del Sistema Biliar/terapia , Resultado del Tratamiento , Supervivencia sin Progresión , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Estadificación de Neoplasias , Terapia Molecular DirigidaRESUMEN
Aim: To determine the prevalence of deleterious mutations in BRCA1 and BRCA2 and in 13 genes involved in homologous recombination repair (HRR), the prevalence of genomic loss of heterozygosity and the allelic and hereditary status of BRCA1, BRCA2 and other HRR gene mutations in multiple solid tumor types. Patients & methods: This was a retrospective observational study of patients with an advanced/metastatic diagnosis in one of 15 solid tumor types, who were identified in a real-world clinico-genomic database. Results: Tumor tissue samples from 9457 patients were analyzed, among which 4.7% had known or suspected deleterious BRCA1/2 mutations. The prevalence (range) of mutations in HRR genes was 13.6% (2.4%-26.0%) and genomic loss of heterozygosity ≥16% was 20.6% (2.6-34.4%) across all tumor types. Conclusion: The prevalence of mutations varied significantly depending on the type of tumor.
The integrity of the human genome is maintained via multiple pathways of DNA repair, one of the most important of which is homologous recombination repair (HRR), which uses a sister chromatid as a template for high-fidelity restoration of altered DNA sequences. This study aimed to determine the prevalence of deleterious mutations, i.e., changes in the genetic code that interfere with proper cellular function, in the breast cancer genes BRCA1 and BRCA2 and in 13 other genes involved in HRR in various types of solid tumors in patients with advanced or metastatic cancer. The researchers found that 4.7% of tumor samples had BRCA1/2 mutations, 13.6% had mutations in any of the HRR genes and 20.6% had genomic loss of heterozygosity (gLOH) of at least 16% i.e., loss of sections of chromosomes affecting 16% or more of the genome. BRCA1/2 mutations were most common in ovarian cancer (13.1%), prostate cancer (9.3%), breast cancer (8.2%) and pancreatic cancer (4.9%). Prevalence for mutations in HRR genes ranges from 2.4 to 26.0% and gLOH ≥16% ranged from 2.6 to 34.4% depending on the tumor type. In conclusion, the prevalence of mutations in the BRCA1/2 genes, HRR genes and gLOH ≥16% varied widely across 15 tumor types.
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INTRODUCTION: Defects in the homologous recombination repair (HRR) pathway can include mutations in BRCA1 and BRCA2 (BRCAm) and other HRR genes (HRRm). These mutations are associated with a homologous recombination deficiency (HRD) phenotype. We evaluated testing journey and treatment patterns by BRCAm, HRRm, and HRD status in a real-world dataset. METHODS: Deidentified data for patients who had undergone comprehensive genomic profiling using FoundationOne®CDx were collected through December 31, 2020, from a real-world multi-tumor clinico-genomic database (CGDB) capturing data from clinics in the United States. Patients eligible for inclusion in this analysis had a confirmed diagnosis with advanced or metastatic disease between January 1, 2018, and December 31, 2019, for 1 of 15 solid tumor types. Objectives were to evaluate patient treatment patterns by BRCAm, HRRm, and HRD status and to describe the timing of when (throughout disease course) comprehensive genomic profiling was performed. RESULTS: Among 9457 patients included in the overall population with evaluable biomarker status, 7856 (83.1%) received ≥ 1 systemic therapy. Among the 7856 patients who received systemic therapy, 2324 (30.0%) underwent testing before first-line therapy, 4114 (52.4%) were tested after receiving first-line therapy and before receiving subsequent therapy (if any), 970 (12.3%) were tested after second-line therapy and before receiving subsequent therapy (if any), and 447 (5.7%) patients underwent testing after receiving third-line therapy. A higher proportion of patients with BRCAm, HRRm, or HRD-positive status were treated with poly(ADP-ribose) polymerase (PARP) inhibitors across all lines of therapy. There was no evidence of a meaningful difference in the proportion of patients who received other treatment (including chemotherapy and immunotherapy) by BRCAm, HRRm, or HRD status. CONCLUSION: The majority of patients from this real-world dataset underwent FoundationOne®CDx testing after initiation of first-line treatment. Testing appeared to influence treatment patterns, with a higher proportion of patients with BRCAm, HRRm, and HRD-positive disease receiving PARP inhibitors.
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Neoplasias , Neoplasias Ováricas , Humanos , Femenino , Reparación del ADN por Recombinación , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Mutación , Biomarcadores , Genómica , Neoplasias Ováricas/patologíaRESUMEN
Aim: To evaluate pembrolizumab in patients of Chinese descent with microsatellite instability-high (MSI-H)/deficient mismatch repair (dMMR) tumors enrolled in KEYNOTE-158 (Cohort L). Methods: Patients with MSI-H/dMMR advanced tumors received pembrolizumab 200 mg IV Q3W. Primary end point was overall response rate (ORR). Secondary end points were duration of response (DOR), progression-free survival (PFS) and overall survival (OS). Results: 24 patients were enrolled (20 were evaluable for efficacy). With median follow-up of 12.4 months, the ORR was 70%. DOR, PFS and OS were all not reached. A total of 19 (79%) patients had a treatment-related adverse event (AE; grade ≥3 in 4 [17%]), and 8 (33%) had an immune-mediated AE (grade ≥3 in (4 [17%]). Conclusion: Pembrolizumab provided meaningful and durable responses with manageable safety. These results are consistent with those reported for the global trial.
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PURPOSE: Mutations in BRCA1 and/or BRCA2 (BRCAm), other homologous recombination repair genes (HRRm), and homologous recombination deficiency (HRD) lead to an accumulation of genomic alterations that can drive tumorigenesis. The prognostic impact of these HRR pathway defects on overall survival (OS) in patients not receiving poly (ADP-ribose) polymerase inhibitors (PARPi) or immunotherapy is unclear. We evaluated the association of HRR biomarkers with OS in patients with advanced solid tumors receiving therapy excluding PARPi and immunotherapy. METHODS: Deidentified data were collected through December 31, 2020, from a real-world clinicogenomic database (CGDB) with data originating from approximately 280 cancer clinics in the United States. Patients age 18 years and older with an advanced/metastatic diagnosis between 2018 and 2019 for 1 of 15 solid tumors and available data in the CGDB were included. The primary analysis evaluated the association between HRR pathway biomarkers and OS, using start of second-line therapy as the index date (to reduce immortal time bias). RESULTS: A total of 9,457 patients had available data for BRCA/HRR and 5,792 for HRD status; 4,890 (51.7%) were women and mean (SD) age was 65.9 (11.5) years. For the primary analysis, adjusted hazard ratios for OS were BRCAm (n = 156) versus BRCA wild-type (wt; n = 3,131; 0.83 [95% CI, 0.60 to 1.17]); for HRRm (n = 467) versus HRRwt (n = 282; 0.95 [95% CI, 0.79 to 1.14]); and for HRD-positive (n = 447) versus -negative (n = 1,687; 1.22 [95% CI, 1.02 to 1.47]). Results were similar using start of first-line and start of third-line therapy as index dates. CONCLUSION: This large, real-world study found no association between OS and either BRCA or HRR status but identified a possible linkage between HRD positivity and shorter median OS in patients with advanced solid tumors who did not receive PARPi or immunotherapy.
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Neoplasias , Reparación del ADN por Recombinación , Humanos , Femenino , Adolescente , Anciano , Masculino , Reparación del ADN por Recombinación/genética , Neoplasias/genética , Neoplasias/terapia , Reparación del ADN , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Biomarcadores de Tumor/genéticaRESUMEN
Triple-negative breast cancers (TNBCs) are defined by a lack of expression of estrogen, progesterone, and HER2 receptors. Because of the absence of identified targets and targeted therapies, and due to a heterogeneous molecular presentation, treatment guidelines for patients with TNBC include only conventional chemotherapy. Such treatment, while effective for some, leaves others with high rates of early relapse and is not curative for any patient with metastatic disease. Here, we demonstrate that these tumors are sensitive to the heat shock protein 90 (Hsp90) inhibitor PU-H71. Potent and durable anti-tumor effects in TNBC xenografts, including complete response and tumor regression, without toxicity to the host are achieved with this agent. Notably, TNBC tumors respond to retreatment with PU-H71 for several cycles extending for over 5 months without evidence of resistance or toxicity. Through a proteomics approach, we show that multiple oncoproteins involved in tumor proliferation, survival, and invasive potential are in complex with PU-H71-bound Hsp90 in TNBC. PU-H71 induces efficient and sustained downregulation and inactivation, both in vitro and in vivo, of these proteins. Among them, we identify downregulation of components of the Ras/Raf/MAPK pathway and G(2)-M phase to contribute to its anti-proliferative effect, degradation of activated Akt and Bcl-xL to induce apoptosis, and inhibition of activated NF-kappaB, Akt, ERK2, Tyk2, and PKC to reduce TNBC invasive potential. The results identify Hsp90 as a critical and multimodal target in this most difficult to treat breast cancer subtype and support the use of the Hsp90 inhibitor PU-H71 for clinical trials involving patients with TNBC.
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Benzodioxoles/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Purinas/farmacología , Antineoplásicos/farmacología , Benzodioxoles/uso terapéutico , Línea Celular Tumoral , Femenino , Humanos , Complejos Multiproteicos/antagonistas & inhibidores , Proteínas de Neoplasias/antagonistas & inhibidores , Purinas/uso terapéutico , Receptor ErbB-2/deficiencia , Receptores de Estrógenos/deficiencia , Receptores de Progesterona/deficiencia , Inducción de RemisiónRESUMEN
A full account of an asymmetric synthesis of reblastatin (1) and the first total synthesis of autolytimycin (2) and related structural compounds is described. The syntheses expand the utility of a highly regio- and diastereoselective hydrometalation aldehyde addition sequence to assemble the fully functionalized ansa chain of the natural products. Also documented is an intramolecular copper-mediated amidation reaction to close the 19-membered macrolactams. The amidation reaction was also employed for the generation of structural derivatives (6-9) of phenolic ansamycins. Ansamycin natural products and selected structural analogues were evaluated in a competitive binding assay to breast cancer cell lysate and a cytotoxicity assay. Both reblastatin (1) and autolytimycin (2) were shown to bind the heat shock protein 90 with enhanced binding activity (approximately 25 nM) than 17-allylamino-17-demethoxygeldanamycin (17-AAG, 4), a geldanamycin (3) derivative currently under evaluation for treatment of cancer (approximately 100 nM).
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Antineoplásicos/síntesis química , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Lactamas Macrocíclicas/síntesis química , Quinonas/síntesis química , Antineoplásicos/química , Antineoplásicos/farmacología , Benzoquinonas/química , Línea Celular Tumoral , Humanos , Lactamas Macrocíclicas/química , Lactamas Macrocíclicas/farmacología , Estructura Molecular , Fenoles/síntesis química , Quinonas/química , Quinonas/farmacología , Relación Estructura-ActividadRESUMEN
The Hsp90 multichaperone complex has important roles in the development and progression of malignant transformation. Several small-molecule inhibitors of Hsp90 of diverse chemotypes have shown potent antitumor activity in a wide-range of malignancies, and are currently in clinical or late-stage preclinical investigation. This review intends to update the reader on advances made over the past two years in the clinical development of Hsp90 inhibitors in advanced cancers. It will refer to the two 17-AAG formulations, tanespimycin and IPI-504, and to synthetic small molecules, among which are the purine-scaffold Hsp90 inhibitor CNF2024/BIIB021, the isoxazole derivative VER-52296/NVP-AUY922, and the carbazol-4-one benzamide derivative SNX-5422, and will present our current knowledge on their clinical performance.
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Antineoplásicos/farmacología , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Animales , Antibióticos Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Benzoquinonas/farmacología , Humanos , Lactamas Macrocíclicas/farmacologíaRESUMEN
Acute myeloid leukemia (AML) is a heterogeneous and fatal disease with an urgent need for improved therapeutic regimens given that most patients die from relapsed disease. Irrespective of mutation status, the development of aggressive leukemias is enabled by increasing dependence on signaling networks. We demonstrate that a hyperactive signalosome drives addiction of AML cells to a tumor-specific Hsp90 species (teHsp90). Through genetic, environmental, and pharmacologic perturbations, we demonstrate a direct and quantitative link between hyperactivated signaling pathways and apoptotic sensitivity of AML to teHsp90 inhibition. Specifically, we find that hyperactive JAK-STAT and PI3K-AKT signaling networks are maintained by teHsp90 and, in fact, gradual activation of these networks drives tumors increasingly dependent on teHsp90. Thus, although clinically aggressive AML survives via signalosome activation, this addiction creates a vulnerability that can be exploited with Hsp90-directed therapy.
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Proteínas HSP90 de Choque Térmico/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Mieloide Aguda/patología , Transducción de Señal/fisiología , Animales , Antineoplásicos/farmacología , Apoptosis/efectos de los fármacos , Apoptosis/fisiología , Benzodioxoles/farmacología , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Humanos , Ratones , Ratones Desnudos , Purinas/farmacología , Transducción de Señal/efectos de los fármacos , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Heat shock protein 70 (Hsp70) is an important emerging cancer target whose inhibition may affect multiple cancer-associated signaling pathways and, moreover, result in significant cancer cell apoptosis. Despite considerable interest from both academia and pharmaceutical companies in the discovery and development of druglike Hsp70 inhibitors, little success has been reported so far. Here we describe structure-activity relationship studies in the first rationally designed Hsp70 inhibitor class that binds to a novel allosteric pocket located in the N-terminal domain of the protein. These 2,5'-thiodipyrimidine and 5-(phenylthio)pyrimidine acrylamides take advantage of an active cysteine embedded in the allosteric pocket to act as covalent protein modifiers upon binding. The study identifies derivatives 17a and 20a, which selectively bind to Hsp70 in cancer cells. Addition of high nanomolar to low micromolar concentrations of these inhibitors to cancer cells leads to a reduction in the steady-state levels of Hsp70-sheltered oncoproteins, an effect associated with inhibition of cancer cell growth and apoptosis. In summary, the described scaffolds represent a viable starting point for the development of druglike Hsp70 inhibitors as novel anticancer therapeutics.
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Acrilamidas/química , Proteínas HSP70 de Choque Térmico/antagonistas & inhibidores , Pirimidinas/química , Sitio Alostérico , Ligandos , Relación Estructura-ActividadRESUMEN
The discovery and development of heat shock protein 70 (Hsp70) inhibitors is currently a hot topic in cancer. In the preceding paper in this issue ( 10.1021/jm401551n ), we have described structure-activity relationship studies in the first Hsp70 inhibitor class rationally designed to bind to a novel allosteric pocket located in the N-terminal domain of the protein. These ligands contained an acrylamide to take advantage of an active cysteine embedded in the allosteric pocket and acted as covalent protein modifiers upon binding. Here, we perform chemical modifications around the irreversible inhibitor scaffold to demonstrate that covalent modification is not a requirement for activity within this class of compounds. The study identifies derivative 27c, which mimics the biological effects of the irreversible inhibitors at comparable concentrations. Collectively, the back-to-back manuscripts describe the first pharmacophores that favorably and selectively interact with a never explored pocket in Hsp70 and provide a novel blueprint for a cancer-oriented development of Hsp70-directed ligands.
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Proteínas HSP70 de Choque Térmico/antagonistas & inhibidores , Pirimidinas/farmacología , Sitio Alostérico , Ligandos , Pirimidinas/química , Relación Estructura-ActividadRESUMEN
Heat shock protein 70 (Hsp70) is a family of proteins with key roles in regulating malignancy. Cancer cells rely on Hsp70 to inhibit apoptosis, regulate senescence and autophagy, and maintain the stability of numerous onco-proteins. Despite these important biological functions in cancer, robust chemical tools that enable the analysis of the Hsp70-regulated proteome in a tumor-by-tumor manner are yet unavailable. Here we take advantage of a recently reported Hsp70 ligand to design and develop an affinity purification chemical toolset for potential use in the investigation of the endogenous Hsp70-interacting proteome in cancer. We demonstrate that these tools lock Hsp70 in complex with onco-client proteins and effectively isolate Hsp70 complexes for identification through biochemical techniques. Using these tools we provide proof-of-concept analyses that glimpse into the complex roles played by Hsp70 in maintaining a multitude of cell-specific malignancy-driving proteins.
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Marcadores de Afinidad , Cromatografía de Afinidad/métodos , Proteínas HSP70 de Choque Térmico/metabolismo , Neoplasias/metabolismo , Línea Celular Tumoral , Proteínas HSP70 de Choque Térmico/aislamiento & purificación , Humanos , Unión ProteicaRESUMEN
Hsp70s are important cancer chaperones that act upstream of Hsp90 and exhibit independent anti-apoptotic activities. To develop chemical tools for the study of human Hsp70, we developed a homology model that unveils a previously unknown allosteric site located in the nucleotide binding domain of Hsp70. Combining structure-based design and phenotypic testing, we discovered a previously unknown inhibitor of this site, YK5. In cancer cells, this compound is a potent and selective binder of the cytosolic but not the organellar human Hsp70s and has biological activity partly by interfering with the formation of active oncogenic Hsp70/Hsp90/client protein complexes. YK5 is a small molecule inhibitor rationally designed to interact with an allosteric pocket of Hsp70 and represents a previously unknown chemical tool to investigate cellular mechanisms associated with Hsp70.