RESUMEN
BACKGROUND: A single-institution experience of pulmonary metastasectomy in soft tissue sarcoma (STS) was retrospectively reviewed. Our specific aim was to examine, whether the resection of pulmonary metastases could be curative. We also compared overall survival (OS) of patients after complete or incomplete pulmonary resection and nonsurgical treatment. METHODS: Between 1987 and 2016, 1580 patients were treated for STS with curative intent by Soft Tissue Sarcoma Group at Helsinki University Hospital, Finland. Three hundred forty-seven patients (22%) developed advanced disease and 130 STS patients (9%) developed pulmonary metastases as first systemic relapse. Seventy four patients (5%) were operated for lung metastases. RESULTS: Fifty-five patients (42%) had a complete and 19 (15%) incomplete resection. Fifty-six (43%) were unoperated. Median OS after complete or incomplete metastasectomy, chemotherapy, or best supportive care was 22, 18, 8, and 5 months, respectively. Twelve patients (9%) developed no further metastases and are alive with no evidence of disease. Disease-free survival (DFS) for completely resected patients was 17% at 5 years. All long-term survivors had oligometastatic disease and they underwent one to three complete metastasectomies. CONCLUSIONS: Complete pulmonary metastasectomy in STS results in 5 years DFS in nearly one-fifth of patients. Most of these patients are probably cured.
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Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/cirugía , Metastasectomía , Neumonectomía , Sarcoma/secundario , Sarcoma/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Sarcoma/mortalidad , Tasa de Supervivencia , Resultado del Tratamiento , Adulto JovenRESUMEN
BACKGROUND/AIM: Almost half of all patients with soft-tissue sarcoma are over 65 years of age, and the proportion of older patients is increasing. Despite this, they have been underrepresented in clinical trials and only limited data are available to guide treatment decisions. The aim of this study was to investigate treatment patterns and outcomes in older patients with soft-tissue sarcoma. PATIENTS AND METHODS: Patients over 50 years old treated for advanced soft-tissue sarcoma at the Helsinki University Hospital between January 2000 and July 2020 were included. Data on patient and tumor characteristics, treatment, and survival were retrospectively collected. A total of 152 patients were included: 14.5% (n=22) were over 75 years old, 34.2% (n=52) were 65-74 and 51.3% (n=78) were 50-64 years old. RESULTS: The outcomes of the oldest group differed from those of younger patients; they were more likely to receive single-agent treatment as first-line therapy (90.9% vs. 28.8% and 24.4%, p<0.001) and had the lowest relative dose-intensity (70% vs. 88% and 95%, p<0.05). They experienced grade three to four hematological adverse events less frequently (38.1%, 56.9% and 72.7%, respectively, p=0.031), and received fewer lines of treatment (median of 1, 2 and 2, respectively, p=0.01). In patients aged ≥75 years, there was no association between further lines of therapy and improved survival. Compared to the youngest group, the oldest patients had a greater risk of dying (hazard ratio=1.7, 95% confidence interval=1.0-2.8, p=0.041) and their median overall survival was only 7.4 months, compared to 14.3 and 12.9 months in the two younger groups. CONCLUSION: These findings suggest that older patients tolerate chemotherapy when treatment is tailored to their needs but may not benefit as much as younger patients.
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Sarcoma , Humanos , Estudios Retrospectivos , Anciano , Masculino , Sarcoma/tratamiento farmacológico , Sarcoma/patología , Sarcoma/mortalidad , Femenino , Persona de Mediana Edad , Anciano de 80 o más Años , Factores de Edad , Resultado del TratamientoRESUMEN
Ultra-low-dose computed tomography (ULD-CT) may combine the high sensitivity of conventional computed tomography (CT) in detecting sarcoma pulmonary metastasis, with a radiation dose in the same magnitude as chest X-ray (CXR). Fifty patients with non-metastatic high-grade soft tissue sarcoma treated with curative intention were recruited. Their follow-up involved both CXR and ULD-CT to evaluate their different sensitivity. Suspected findings were confirmed by conventional CT if necessary. Patients with isolated pulmonary metastases were treated with surgery or stereotactic body radiation therapy (SBRT) with curative intent if possible. The median effective dose from a single ULD-CT study was 0.27 mSv (range 0.12 to 0.89 mSv). Nine patients were diagnosed with asymptomatic lung metastases during the follow-up. Only three of them were visible in CXR and all nine in ULD-CT. CXR had therefore only a 33% sensitivity compared to ULD-CT. Four patients were operated, and one had SBRT to all pulmonary lesions. Eight of them, however, died of the disease. Two patients developed symptomatic metastatic recurrence involving extrapulmonary sites+/-the lungs between two imaging rounds. ULD-CT has higher sensitivity for the detection of sarcoma pulmonary metastasis than CXR, with a radiation dose considerably lower than conventional CT.Clinical trial registration: NCT05813808. 04-14-2023.
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Neoplasias Pulmonares , Sarcoma , Humanos , Estudios de Seguimiento , Neoplasias Pulmonares/secundario , Estudios Prospectivos , Dosis de Radiación , Sarcoma/patología , Tomografía Computarizada por Rayos X/métodos , Rayos XRESUMEN
BACKGROUND: PSA is the most useful prostate cancer marker. However, its levels are increased also in some non-malignant conditions. In circulation, the majority of PSA is complexed with protease inhibitors, including α(1) -antichymotrypsin (ACT). The proportion of the PSA-ACT complex is higher in patients with prostate cancer than in controls without cancer. The expression of ACT has been shown to be higher in prostate cancer than in benign prostatic hyperplasia. However, results regarding the extent which PSA forms complexes within the prostate and whether there are differences in complex formation between normal and malignant prostatic tissue are inconsistent and limited. METHODS: We studied complex formation of PSA secreted by cultured human prostate tissues and in the tissue by in situ proximity ligation assay (PLA). Free, total and active PSA, and the PSA-ACT complex were determined in tissue culture media by immunoassays, immunoblotting, and chromatographic methods. RESULTS: The majority of PSA in tissue culture medium was free and enzymatically active. However, a significant proportion (1.6 ± 0.5%) of immunoreactive PSA was found to be complexed with ACT. Complex formation was confirmed by in situ PLA, which showed more intense staining of PSA-ACT in cancers with Gleason grade 3 than in adjacent benign tissues from the same patients. CONCLUSIONS: These results show that PSA forms complexes already within the prostate and that PSA-ACT levels are increased in moderately differentiated prostate cancer tissue. This may explain, at least partially, why the ratio of serum PSA-ACT to total PSA is increased in prostate cancer.
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Antígeno Prostático Específico/metabolismo , Próstata/metabolismo , Neoplasias de la Próstata/metabolismo , alfa 1-Antiquimotripsina/metabolismo , Adulto , Anciano , Diferenciación Celular/fisiología , Humanos , Masculino , Persona de Mediana Edad , Complejos Multiproteicos/metabolismo , Próstata/patología , Neoplasias de la Próstata/diagnóstico , Unión Proteica/fisiologíaRESUMEN
BACKGROUND: The quality of surgical margins is the most important factor affecting local control in soft tissue sarcoma (STS). Despite this, there is no universally accepted consensus on the definition of an adequate surgical margin or on which patients should be offered radiation therapy. This study focuses on local control and its prognostic factors in patients with trunk wall and extremity STS. METHODS: Adult patients with a final diagnosis of trunk wall or extremity STS referred to a single tertiary referral centre between August 1987 and December 2016 were identified from a prospective institutional database. Patients were treated according to a protocol instituted in 1987. The classification of surgical margins and indications for radiation therapy were based on anatomy and strict definition of surgical margins as metric distance to the resection border. Local treatment was defined as adequate if patients received either surgery with wide margins alone or marginal surgery combined with radiation therapy. Margins were considered wide if the tumour was excised with pathological margins greater than 2.5 cm or with an uninvolved natural anatomical barrier. After treatment, patients were followed up with local imaging and chest X-ray: 5 years for high-grade STS, 10 years for low-grade STS. RESULTS: A total of 812 patients were included with a median follow-up of 5.8 (range 0.5-19.5) years. Forty-four patients had a grade 1 tumour: there were no instances of recurrence in this group thus they were excluded from further analysis. Five-year local control in the 768 patients with grade 2-3 STS was 90.1 per cent in patients receiving adequate local treatment according to the protocol. Altogether, 333 patients (43.4 per cent) were treated with wide surgery alone and their 5-year local control rate was 91.1 per cent. Among patients treated with wide surgery alone, deep location was the only factor adversely associated with local relapse risk in multivariable analysis; 5-year local control was 95.3 per cent in superficial and 88.3 per cent in deep-sited sarcomas (hazards ratio 3.154 (95% c.i. 1.265 to 7.860), P = 0.014). CONCLUSION: A high local control rate is achievable with surgery alone for a substantial proportion of patients with STS of the extremities or superficial trunk wall.
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Sarcoma , Neoplasias de los Tejidos Blandos , Adulto , Humanos , Márgenes de Escisión , Estudios Prospectivos , Recurrencia Local de Neoplasia/patología , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Neoplasias de los Tejidos Blandos/radioterapia , Neoplasias de los Tejidos Blandos/cirugía , Extremidades/cirugía , Extremidades/patología , Sarcoma/diagnóstico por imagen , Sarcoma/radioterapia , Sarcoma/cirugía , RecurrenciaRESUMEN
BACKGROUND: Prostate and seminal vesicle are two similar hormone responsive human organs that differ dramatically in their cancer incidence. DNA damage response (DDR) is required for maintenance of genomic integrity. METHODS: In this study we investigated the DDR and cell cycle checkpoint activation of these organs using orthotopic cultures of human surgery-derived tissues and primary cultures of isolated prostate and seminal vesicle cells. RESULTS: We find that the activation of ATM signaling pathway by ionizing radiation (IR) was comparable in both tissues. Previously, we have shown that the prostate secretory cells express low levels of histone variant H2AX and phosphorylated H2AX (γH2AX) after IR. Here we demonstrate that H2AX levels are low also in the secretory seminal vesicle cells suggesting that this is a common phenotype of postmitotic cells. We consequently established primary epithelial cell cultures from both organs to compare their DDR. Interestingly, contrary to human prostate epithelial cells (HPEC), primary seminal vesicle epithelial cells (HSVEC) displayed effective cell cycle checkpoints after IR and expressed higher levels of Wee1A checkpoint kinase. Furthermore, HSVEC but not HPEC cells were able to activate p53 and to induce p21 cell cycle inhibitor. DISCUSSION: Our results show that during replication, the checkpoint enforcement is more proficient in the seminal vesicle than in the prostate epithelium cells. This indicates a more stringent enforcement of DDR in replicating seminal vesicle epithelial cells, and suggests that epithelial regeneration combined with sub-optimal checkpoint responses may contribute to high frequency of genetic lesions in the prostate epithelium.
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Puntos de Control del Ciclo Celular/genética , Daño del ADN/genética , Células Epiteliales/fisiología , Próstata/fisiología , Vesículas Seminales/fisiología , Células Cultivadas , Células Epiteliales/patología , Epitelio/patología , Epitelio/fisiología , Humanos , Masculino , Próstata/patología , Vesículas Seminales/patologíaRESUMEN
BACKGROUND/AIM: The aim of this prospective study was to determine whether serum Thymidine kinase -1 (TK1) could serve as a tumor marker in soft tissue sarcomas (STS). PATIENTS AND METHODS: A total of 48 patients diagnosed with localized STS were included. None had received preoperative oncological treatment. Samples were collected before and after surgery and TK1 levels measured with the AroCell TK210 ELISA. RESULTS: Mean preoperative TK1 was 0.32 µg/l, range=0.11-1.47, and 18 cases (38%) had values above the reference limit (0.41 µg/l). Mean postoperative TK1 was 0.35 µg/l (0.06-0.86). In patients with preoperative values above the reference limit, TK1 decreased significantly after surgery (n=13, p=0.001). We found no association between increased preoperative TK1 and age, sex, tumor size, grade, and the presence of vascular invasion or necrosis. CONCLUSION: TK1 has limited use as a tumor marker in localized STS.
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Biomarcadores de Tumor/sangre , Sarcoma/sangre , Neoplasias de los Tejidos Blandos/sangre , Timidina Quinasa/sangre , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Estudios Prospectivos , Sarcoma/diagnóstico , Sarcoma/enzimología , Sarcoma/cirugía , Neoplasias de los Tejidos Blandos/diagnóstico , Neoplasias de los Tejidos Blandos/enzimología , Neoplasias de los Tejidos Blandos/cirugía , Resultado del Tratamiento , Adulto JovenRESUMEN
Kaposi sarcoma is a tumor consisting of Kaposi sarcoma herpesvirus (KSHV)-infected tumor cells that express endothelial cell (EC) markers and viral genes like v-cyclin, vFLIP, and LANA. Despite a strong link between KSHV infection and certain neoplasms, de novo virus infection of human primary cells does not readily lead to cellular transformation. We have studied the consequences of expression of v-cyclin in primary and immortalized human dermal microvascular ECs. We show that v-cyclin, which is a homolog of cellular D-type cyclins, induces replicative stress in ECs, which leads to senescence and activation of the DNA damage response. We find that antiproliferative checkpoints are activated upon KSHV infection of ECs, and in early-stage but not late-stage lesions of clinical Kaposi sarcoma specimens. These are some of the first results suggesting that DNA damage checkpoint response also functions as an anticancer barrier in virally induced cancers.
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Daño del ADN , ADN Viral , Sarcoma de Kaposi/etiología , Sarcoma de Kaposi/virología , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/virología , Proteínas Virales/biosíntesis , Ciclo Celular , Centrosoma/fisiología , Células Endoteliales/fisiología , Células Endoteliales/virología , Herpesvirus Humano 8 , Humanos , Fase S/efectos de los fármacos , Sarcoma de Kaposi/patologíaRESUMEN
BACKGROUND: The etiology of facial paresis (FP) often remains unresolved. Yet, a microbial association is frequently suspected. OBJECTIVE: To evaluate the infectious etiology of FP by using sensitive tests. STUDY DESIGN: We studied the serum and cerebrospinal fluid of 42 patients diagnosed with idiopathic peripheral facial paresis using sensitive serological methods and nucleic acid detection and for reference, 42 patients with other neurological disorders (OND) matched for age, sex, season and geographical area. RESULTS: Varicella zoster virus and Borrelia burgdorferi accounted for 56% of all associated agents in children with FP compared with 11% of OND (P=0.01). In adults, the respective numbers were 29 and 13%. Other treatable etiological agents, Chlamydia pneumoniae and Mycoplasma pneumoniae, accounted for 11% in children and 8% in adults and with the same prevalence between patients with FP and OND. CONCLUSIONS: Microbes, with specific therapy available accounted for 52% of all associated agents in the patients with FP when compared with 26% in controls with OND (P=0.04). Based on this, we conclude that the patients with FP may benefit from antimicrobial therapy.
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Borrelia burgdorferi/aislamiento & purificación , Parálisis Facial/microbiología , Herpesvirus Humano 3/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Antibacterianos/sangre , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/líquido cefalorraquídeo , Borrelia burgdorferi/inmunología , Niño , Preescolar , Chlamydophila pneumoniae/inmunología , Chlamydophila pneumoniae/aislamiento & purificación , ADN Viral/líquido cefalorraquídeo , Parálisis Facial/sangre , Parálisis Facial/líquido cefalorraquídeo , Femenino , Herpesvirus Humano 3/genética , Herpesvirus Humano 3/inmunología , Humanos , Masculino , Persona de Mediana Edad , Mycoplasma pneumoniae/inmunología , Mycoplasma pneumoniae/aislamiento & purificaciónRESUMEN
Activation of the p53 pathway has been considered a therapeutic strategy to target cancers. We have previously identified several p53-activating small molecules in a cell-based screen. Two of the compounds activated p53 by causing DNA damage, but this modality was absent in the other four. We recently showed that one of these, BMH-21, inhibits RNA polymerase I (Pol I) transcription, causes the degradation of Pol I catalytic subunit RPA194, and has potent anticancer activity. We show here that three remaining compounds in this screen, BMH-9, BMH-22, and BMH-23, cause reorganization of nucleolar marker proteins consistent with segregation of the nucleolus, a hallmark of Pol I transcription stress. Further, the compounds destabilize RPA194 in a proteasome-dependent manner and inhibit nascent rRNA synthesis and expression of the 45S rRNA precursor. BMH-9- and BMH-22-mediated nucleolar stress was detected in ex vivo-cultured human prostate tissues indicating good tissue bioactivity. Testing of closely related analogues showed that their activities were chemically constrained. Viability screen for BMH-9, BMH-22, and BMH-23 in the NCI60 cancer cell lines showed potent anticancer activity across many tumor types. Finally, we show that the Pol I transcription stress by BMH-9, BMH-22, and BMH-23 is independent of p53 function. These results highlight the dominant impact of Pol I transcription stress on p53 pathway activation and bring forward chemically novel lead molecules for Pol I inhibition, and, potentially, cancer targeting.
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Nucléolo Celular/efectos de los fármacos , ARN Polimerasa I/antagonistas & inhibidores , Bibliotecas de Moléculas Pequeñas/farmacología , Neoplasias Óseas/tratamiento farmacológico , Línea Celular Tumoral , Inhibidores Enzimáticos/farmacología , Células HCT116 , Humanos , Masculino , Melanoma/tratamiento farmacológico , Osteosarcoma/tratamiento farmacológico , Próstata/efectos de los fármacosRESUMEN
MicroRNAs (miRNAs) are important and ubiquitous regulators of gene expression that can suppress their target genes by translational inhibition as well as mRNA destruction. Cell type-specific miRNA expression patterns have been successfully exploited for targeting the expression of experimental and therapeutic gene constructs, for example to reduce pathogenic effects of cancer virotherapy in normal tissues. In order to avoid liver damage associated with systemic or intrahepatic delivery of oncolytic adenoviruses we have introduced the concept of suppressing adenovirus replication in hepatic cells by inserting target elements for the liver-specific miR122 into the viral genome. Here we show using ex vivo cultured tissue specimens that six perfectly complementary miR122 target sites in the 3' untranslated region of the viral E1A gene are sufficient in the absence of any other genetic modifications to prevent productive replication of serotype 5 adenovirus (Ad5) in normal human liver. This modification did not compromise the replicative capacity of the modified virus in cancer tissue derived from a colon carcinoma liver metastasis or its oncolytic potency in a human lung cancer xenograft mouse model. Unlike wild-type Ad5, the modified virus did not result in increased serum levels of liver enzymes in infected mice. These results provide a strong preclinical proof of concept for the use of miR122 target sites for reducing the risk of liver damage caused by oncolytic adenoviruses, and suggest that ectopic miR122 target elements should be considered as an additional safety measure included in any therapeutic virus or viral vector posing potential hazard to the liver.
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Adenoviridae/genética , Neoplasias del Colon/genética , Terapia Genética , MicroARNs/genética , Virus Oncolíticos/genética , Proteínas E1A de Adenovirus/genética , Proteínas E1A de Adenovirus/metabolismo , Animales , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/virología , Regulación de la Expresión Génica , Genoma Viral , Humanos , Hígado/metabolismo , Hígado/virología , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/virología , Ratones , MicroARNs/metabolismo , Metástasis de la Neoplasia , Especificidad de Órganos , Trasplante Heterólogo , Replicación Viral/genéticaRESUMEN
Prostate cancer is one of the most frequent cancer types in men, and its incidence is steadily increasing. On the other hand, primary seminal vesicle carcinomas are extremely rare with less than 60 cases reported worldwide. Therefore the difference in cancer incidence has been estimated to be more than a 100,000-fold. This is astonishing, as both tissues share similar epithelial structure and hormonal cues. Clearly, the two epithelia differ substantially in the maintenance of genomic integrity, possibly due to inherent differences in their DNA damage burden and DNA damage signaling. The DNA damage response evoked by DNA double strand breaks may be relevant, as their faulty repair has been implicated in the formation of common genomic rearrangements such as TMPRSS2-ERG fusions during prostate carcinogenesis. Here, we review DNA damaging processes of both tissues with an emphasis on inflammation and androgen signaling. We discuss how benign prostate and seminal vesicle epithelia respond to acute DNA damage, focusing on the canonical DNA double strand break-induced ATM-pathway, p53 and DNA damage induced checkpoints. We propose that the prostate might be more prone to the accumulation of genetic aberrations during epithelial regeneration than seminal vesicles due to a weaker ability to enforce DNA damage checkpoints.
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Roturas del ADN de Doble Cadena , ADN/genética , Próstata/patología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Vesículas Seminales/patología , Andrógenos/metabolismo , Humanos , Masculino , Próstata/metabolismo , Neoplasias de la Próstata/metabolismo , Vesículas Seminales/metabolismoRESUMEN
The ability of cells to respond and repair DNA damage is fundamental for the maintenance of genomic integrity. Ex vivo culturing of surgery-derived human tissues has provided a significant advancement to assess DNA damage response (DDR) in the context of normal cytoarchitecture in a non-proliferating tissue. Here, we assess the dependency of prostate epithelium DDR on ATM and DNA-PKcs, the major kinases responsible for damage detection and repair by nonhomologous end-joining (NHEJ), respectively. DNA damage was caused by ionizing radiation (IR) and cytotoxic drugs, cultured tissues were treated with ATM and DNA-PK inhibitors, and DDR was assessed by phosphorylation of ATM and its targets H2AX and KAP1, a heterochromatin binding protein. Phosphorylation of H2AX and KAP1 was fast, transient and fully dependent on ATM, but these responses were moderate in luminal cells. In contrast, DNA-PKcs was phosphorylated in both luminal and basal cells, suggesting that DNA-PK-dependent repair was also activated in the luminal cells despite the diminished H2AX and KAP1 responses. These results indicate that prostate epithelial cell types have constitutively dissimilar responses to DNA damage. We correlate the altered damage response to the differential chromatin state of the cells. These findings are relevant in understanding how the epithelium senses and responds to DNA damage.
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Proteínas de Ciclo Celular/metabolismo , Daño del ADN , Reparación del ADN por Unión de Extremidades/fisiología , Proteína Quinasa Activada por ADN/metabolismo , Proteínas de Unión al ADN/metabolismo , Epitelio/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal/fisiología , Proteínas Supresoras de Tumor/metabolismo , Proteínas de la Ataxia Telangiectasia Mutada , Células Cultivadas , Histonas/metabolismo , Humanos , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Masculino , Microscopía Confocal , Microscopía Fluorescente , Fosforilación , Próstata/citología , Radiación Ionizante , Proteínas Represoras/metabolismo , Proteína 28 que Contiene Motivos TripartitoRESUMEN
Manipulation of the activity of the p53 tumor suppressor pathway has demonstrated potential benefit in preclinical mouse tumor models and has entered human clinical trials. We describe here an improved, extensive small-molecule chemical compound library screen for p53 pathway activation in a human cancer cell line devised to identify hits with potent antitumor activity. We uncover six novel small-molecule lead compounds, which activate p53 and repress the growth of human cancer cells. Two tested compounds suppress in vivo tumor growth in an orthotopic mouse model of human B-cell lymphoma. All compounds interact with DNA, and two activate p53 pathway in a DNA damage signaling-dependent manner. A further screen of a drug library of approved drugs for medicinal uses and analysis of gene-expression signatures of the novel compounds revealed similarities to known DNA intercalating and topoisomerase interfering agents and unexpected connectivities to known drugs without previously demonstrated anticancer activities. These included several neuroleptics, glycosides, antihistamines and adrenoreceptor antagonists. This unbiased screen pinpoints interference with the DNA topology as the predominant mean of pharmacological activation of the p53 pathway and identifies potential novel antitumor agents.
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Antineoplásicos/farmacología , Ensayos de Selección de Medicamentos Antitumorales , Neoplasias/metabolismo , Transducción de Señal/efectos de los fármacos , Bibliotecas de Moléculas Pequeñas/farmacología , Proteína p53 Supresora de Tumor/metabolismo , Animales , Antineoplásicos/uso terapéutico , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Ratones , Neoplasias/tratamiento farmacológico , Neoplasias/genética , Neoplasias/fisiopatología , Bibliotecas de Moléculas Pequeñas/uso terapéutico , Proteína p53 Supresora de Tumor/genéticaRESUMEN
DNA damage response (DDR) pathways have been extensively studied in cancer cell lines and mouse models, but little is known about how DNA damage is recognized by different cell types in nonmalignant, slowly replicating human tissues. Here, we assess, using ex vivo cultures of human prostate tissue, DDR caused by cytotoxic drugs (camptothecin, doxorubicin, etoposide, and cisplatin) and ionizing radiation (IR) in the context of normal tissue architecture. Using specific markers for basal and luminal epithelial cells, we determine and quantify cell compartment-specific damage recognition. IR, doxorubicin, and etoposide induced the phosphorylation of H2A.X on Ser(139) (γH2AX) and DNA damage foci formation. Surprisingly, luminal epithelial cells lack the prominent γH2AX response after IR when compared with basal cells, although ATM phosphorylation on Ser(1981) and 53BP1 foci were clearly detectable in both cell types. The attenuated γH2AX response seems to result from low levels of total H2A.X in the luminal cells. Marked increase in p53, a downstream target of the activated ATM pathway, was detected only in response to camptothecin and doxorubicin. These findings emphasize the diversity of pathways activated by DNA damage in slowly replicating tissues and reveal an unexpected deviation in the prostate luminal compartment that may be relevant in prostate tumorigenesis. Detailed mapping of tissue and cell type differences in DDR will provide an outlook of relevant responses to therapeutic strategies.
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Proteínas de Ciclo Celular/metabolismo , Daño del ADN/fisiología , Proteínas de Unión al ADN/metabolismo , Próstata/metabolismo , Próstata/patología , Proteínas Serina-Treonina Quinasas/metabolismo , Transducción de Señal , Proteína p53 Supresora de Tumor/metabolismo , Proteínas Supresoras de Tumor/metabolismo , Antineoplásicos/farmacología , Proteínas de la Ataxia Telangiectasia Mutada , Daño del ADN/efectos de la radiación , Histonas/metabolismo , Humanos , Técnicas para Inmunoenzimas , Péptidos y Proteínas de Señalización Intracelular , Masculino , Fosforilación/efectos de la radiación , Radiación Ionizante , Proteína 1 de Unión al Supresor Tumoral P53RESUMEN
Cellular DNA damage triggers the DNA damage response pathway and leads to enforcement of cell cycle checkpoints, which are essential for the maintenance of genomic integrity and are activated in early stages of tumorigenesis. A special feature of prostate cancer is its high incidence and multifocality. To address the functionality of DNA damage checkpoints in the prostate, we analyzed the responses of human primary prostate epithelial cells (HPECs) and freshly isolated human prostate tissues to gamma-irradiation. We find that gamma-irradiation activates the ataxia telangiectasia mutated-associated DNA damage response pathway in the HPECs but that the clearance of phosphorylated histone H2AX (gammaH2AX) foci is delayed. Surprisingly, gamma-irradiated HPECs were unable to enforce cell cycle checkpoint arrest and had sustained cyclin-dependent kinase 2 (Cdk2)-associated kinase activity because of a lack of inhibitory Cdk phosphorylation by Wee1A tyrosine kinase. We further show that HPECs express low levels of Wee1A and that ectopic Wee1A efficiently rescues the checkpoints. We recapitulate the absence of checkpoint responses in epithelium of ex vivo irradiated human prostate tissue despite robust induction of gammaH2AX. The findings show that prostate epithelium has a surprising inability to control checkpoint arrest, the lack of which may predispose to accrual of DNA lesions.