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Background: Total hysterectomy with bilateral salpingo-oophorectomy via minimally invasive surgery (MIS) has emerged as the standard of care for early-stage endometrial cancer (EC). Prior systematic reviews and meta-analyses have focused on outcomes reported solely from randomised controlled trials (RCTs), overlooking valuable data from non-randomised studies. This inaugural systematic review and network meta-analysis comprehensively compares clinical and oncological outcomes between MIS and open surgery for early-stage EC, incorporating evidence from randomised and non-randomised studies. Methods: This study was prospectively registered on PROSPERO (CRD42020186959). All original research of any experimental design reporting clinical and oncological outcomes of surgical treatment for endometrial cancer was included. Study selection was restricted to English-language peer-reviewed journal articles published 1 January 1995-31 December 2021. A Bayesian network meta-analysis was conducted. Results: A total of 99 studies were included in the network meta-analysis, comprising 181,716 women and 14 outcomes. Compared with open surgery, laparoscopic and robotic-assisted surgery demonstrated reduced blood loss and length of hospital stay but increased operating time. Compared with laparoscopic surgery, robotic-assisted surgery was associated with a significant reduction in ileus (OR = 0.40, 95% CrI: 0.17-0.87) and total intra-operative complications (OR = 0.38, 95% CrI: 0.17-0.75) as well as a higher disease-free survival (OR = 2.45, 95% CrI: 1.04-6.34). Conclusions: For treating early endometrial cancer, minimal-access surgery via robotic-assisted or laparoscopic techniques appears safer and more efficacious than open surgery. Robotic-assisted surgery is associated with fewer complications and favourable oncological outcomes.
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Müllerian anomalies such as Robert's uterus, which was first described by the French gynaecologist Dr Helene Robert in 1969, are rare clinical entities and have been reported in <3% of the female population. Robert's uterus is a rare phenomenon with a relative dearth of reported cases. Affected individuals may present with pelvic pain and dysmenorrhoea that intensifies near menses or acutely, with severe abdominal pain to the emergency department. They are also associated with adverse pregnancy outcomes, abnormal fetal presentation, preterm labour, recurrent pregnancy loss and infertility. Although ultrasound has a role in its initial assessment, MRI is the best modality to further delineate its anatomy. It is typically managed via laparotomy and total horn resection, endometrectomy of the blind cavity or abdominal metroplasty. The authors present the case of a 40-year-old woman at 19+3 weeks gestation with acute onset of left-sided abdominal pain. A transvaginal ultrasound and MRI of the pelvis confirmed a Robert's uterus with a viable pregnancy in the upper left horn. She developed a ruptured horn with significant haemoperitoneum. An emergency laparotomy was performed and a non-viable fetus was evident. Only a few cases of pregnancy in the blind hemicavity have been reported so far. This case also highlights the importance of considering this diagnosis in young females presenting with dysmenorrhoea and normal menstrual flow. It is imperative to render a prompt diagnosis, as minimally invasive procedures may be more effective if detected before the formation of adnexal endometriomas.
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Dismenorrea , Conductos Paramesonéfricos , Dolor Abdominal , Adulto , Dismenorrea/etiología , Femenino , Humanos , Recién Nacido , Conductos Paramesonéfricos/anomalías , Conductos Paramesonéfricos/cirugía , Pelvis , Embarazo , Útero/anomalías , Útero/diagnóstico por imagen , Útero/cirugíaRESUMEN
Early diagnosis of the rare and life-threatening uterine leiomyosarcoma (LMS) is essential for prompt treatment, to improve survival. Preoperative distinction of LMS from benign leiomyoma remains a challenge, and thus LMS is often diagnosed post-operatively. This retrospective observational study evaluated the predictive diagnostic utility of 32 preoperative variables in 190 women who underwent a hysterectomy, with a postoperative diagnosis of leiomyoma (n = 159) or LMS (n = 31), at the Liverpool Women's National Health Service (NHS) Foundation Trust, between 2010 and 2019. A total of 7 preoperative variables were associated with increased odds of LMS, including postmenopausal status (p < 0.001, OR 3.08), symptoms of pressure (p = 0.002, OR 2.7), postmenopausal bleeding (p = 0.001, OR 5.01), neutrophil count ≥7.5 × 109/L (p < 0.001, OR 5.72), haemoglobin level <118 g/L (p = 0.037, OR 2.22), endometrial biopsy results of cellular atypia or neoplasia (p = 0.001, OR 9.6), and a mass size of ≥10 cm on radiological imaging (p < 0.0001, OR 8.52). This study has identified readily available and easily identifiable preoperative clinical variables that can be implemented into clinical practice to discern those with high risk of LMS, for further specialist investigations in women presenting with symptoms of leiomyoma.
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OBJECTIVES: Surgical site infection (SSI) complicates 5% of all surgical procedures in the UK and is a major cause of postoperative morbidity and a substantial drain on healthcare resources. Little is known about the incidence of SSI and its consequences in women undergoing surgery for gynaecological cancer. Our aim was to perform the first national audit of SSI following gynaecological cancer surgery through the establishment of a UK-wide trainee-led research network. DESIGN AND SETTING: In a prospective audit, we collected data from all women undergoing laparotomy for suspected gynaecological cancer at 12 specialist oncology centres in the UK during an 8-week period in 2015. Clinicopathological data were collected, and wound complications and their sequelae were recorded during the 30 days following surgery. RESULTS: In total, 339 women underwent laparotomy for suspected gynaecological cancer during the study period. A clinical diagnosis of SSI was made in 54 (16%) women. 33% (18/54) of women with SSI had prolonged hospital stays, and 11/37 (29%) had their adjuvant treatment delayed or cancelled. Multivariate analysis found body mass index (BMI) was the strongest risk factor for SSI (OR 1.08[95% CI 1.03 to 1.14] per 1 kg/m2 increase in BMI [p=0.001]). Wound drains (OR 2.92[95% CI 1.41 to 6.04], p=0.004) and staple closure (OR 3.13[95% CI 1.50 to 6.56], p=0.002) were also associated with increased risk of SSI. CONCLUSIONS: SSI is common in women undergoing surgery for gynaecological cancer leading to delays in discharge and adjuvant treatment. Resultant delays in adjuvant treatment may impact cancer-specific survival rates. Modifiable factors, such as choice of wound closure material, offer opportunities for reducing SSI and reducing morbidity in these women. There is a clear need for new trials in SSI prevention in this patient group; our trainee-led initiative provides a platform for their successful completion.
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Auditoría Clínica , Neoplasias de los Genitales Femeninos/cirugía , Laparotomía/efectos adversos , Complicaciones Posoperatorias/epidemiología , Infección de la Herida Quirúrgica/epidemiología , Anciano , Índice de Masa Corporal , Femenino , Neoplasias de los Genitales Femeninos/patología , Humanos , Incidencia , Tiempo de Internación/estadística & datos numéricos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Succión , Suturas/efectos adversos , Reino Unido/epidemiologíaRESUMEN
OBJECTIVES: To identify the top 10 unanswered research questions for primary care patient safety research. DESIGN: A modified nominal group technique. SETTING: UK. PARTICIPANTS: Anyone with experience of primary care including: patients, carers and healthcare professionals. 341 patients and 86 healthcare professionals submitted questions. MAIN OUTCOMES: A top 10, and top 30, future research questions for primary care patient safety. RESULTS: 443 research questions were submitted by 341 patients and 86 healthcare professionals, through a national survey. After checking for relevance and rephrasing, a total of 173 questions were collated into themes. The themes were largely focused on communication, team and system working, interfaces across primary and secondary care, medication, self-management support and technology. The questions were then prioritised through a national survey, the top 30 questions were taken forward to the final prioritisation workshop. The top 10 research questions focused on the most vulnerable in society, holistic whole-person care, safer communication and coordination between care providers, work intensity, continuity of care, suicide risk, complex care at home and confidentiality. CONCLUSIONS: This study was the first national prioritisation exercise to identify patient and healthcare professional priorities for primary care patient safety research. The research priorities identified a range of important gaps in the existing evidence to inform everyday practice to address primary care patient safety.
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Prioridades en Salud/estadística & datos numéricos , Participación del Paciente , Seguridad del Paciente , Atención Primaria de Salud/métodos , Adolescente , Adulto , Anciano , Investigación Biomédica/tendencias , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Reino Unido , Adulto JovenRESUMEN
Despite numerous advances in "omics" research, early detection of ovarian cancer still remains a challenge. The aim of this study was to determine whether attenuated total reflection Fourier-transform infrared (ATR-FTIR) or Raman spectroscopy could characterise alterations in the biomolecular signatures of human blood plasma/serum obtained from ovarian cancer patients compared to non-cancer controls. Blood samples isolated from ovarian cancer patients (n = 30) and healthy controls (n = 30) were analysed using ATR-FTIR spectroscopy. For comparison, a smaller cohort of samples (n = 8) were analysed using an InVia Renishaw Raman spectrometer. Resultant spectra were pre-processed prior to being inputted into principal component analysis (PCA) and linear discriminant analysis (LDA). Statistically significant differences (P < 0.001) were observed between spectra of ovarian cancer versus control subjects for both biospectroscopy methods. Using a support vector machine classifier for Raman spectra of blood plasma, a diagnostic accuracy of 74% was achieved, while the same classifier showed 93.3% accuracy for IR spectra of blood plasma. These observations suggest that a biospectroscopy approach could be applied to identify spectral alterations associated with the presence of insidious ovarian cancer.
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Biomarcadores de Tumor/sangre , Neoplasias Ováricas/sangre , Neoplasias Ováricas/diagnóstico , Suero/química , Adulto , Anciano , Análisis Discriminante , Detección Precoz del Cáncer , Femenino , Humanos , Modelos Lineales , Persona de Mediana Edad , Análisis Multivariante , Proyectos Piloto , Análisis de Componente Principal , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Programas Informáticos , Espectroscopía Infrarroja por Transformada de Fourier , Espectrometría Raman/métodos , Máquina de Vectores de Soporte , VibraciónRESUMEN
A new series of quinoline ether inhibitors, which potently and selectively inhibit PDGFR tyrosine kinases, is described in this Letter. Compounds 23 and 33 are selective, low nanomolar inhibitors of PDGFRα and ß, display good pharmacokinetics in rat and dog and are active in vivo at low doses when given orally twice daily. Further evaluation of these compounds is warranted.
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Éteres/farmacología , Quinolinas/farmacología , Receptores del Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Animales , Perros , Relación Dosis-Respuesta a Droga , Descubrimiento de Drogas , Proteínas Tirosina Quinasas/antagonistas & inhibidores , RatasRESUMEN
A new series of Quinazoline Ether Inhibitor which potently inhibits VEGFR-2 and PDGFR tyrosine kinases is described here. In vitro, pharmacokinetics and in vivo evaluations led to the selection of AZD2932.
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Éteres/síntesis química , Éteres/farmacología , Quinazolinas/síntesis química , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Algoritmos , Animales , Química Farmacéutica/métodos , Perros , Diseño de Fármacos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Femenino , Humanos , Concentración 50 Inhibidora , Masculino , Modelos Químicos , Fosforilación , Quinazolinas/farmacología , RatasRESUMEN
AIMS: Ovarian cancer has the highest mortality of any gynaecological malignancy; this is due to rapid peritoneal spread of tumour cells and neovascularization. Understanding the mechanisms underlying this is critical to developing early diagnostic or treatment strategies. We devised a pilot study to examine the role of γ-SYNUCLEIN (γ-SYN), oestrogen receptor (ER)α, and the splice variant ERαΔ3. METHODOLOGY: With ethical approval, ovarian tissue was collected from patients (n=24) undergoing oopherectomy for non-ovarian pathology or primary surgery for suspected ovarian cancer. Quantitative gene expression analysis was employed for γ-SYN, ERα, and ERαΔ3. To identify the in situ localization, immunofluorescence for γ-syn was carried out. RESULTS: Ovarian tumour tissue exhibited an elevated expression of γ-SYN and high-grade tumours had an elevated ERαΔ3:ERα ratio compared with benign tissue. The majority of previous studies point to the γ-syn protein being present in epithelial cells of high-grade disease. Our study supports this, but additionally we conclusively identify its presence in the endothelial cells of vasculature surrounding low-grade disease; immunofluorescence was strongest in the apical cells surrounding the lumen. CONCLUSION: Our results demonstrate for the first time that there are readily-expressed levels of γ-SYN and ERαΔ3 in normal ovarian tissue and ovarian tumours. In high-grade disease, γ-syn and an elevated ERαΔ3:ERα ratio might confer metastatic potential to the tumourigenic cells and promote neoangiogenesis. Future in vitro studies might be necessary to delineate such a mechanism, which could potentially be the basis of early intervention.
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Cediranib is a potent inhibitor of the VEGF receptor (VEGFR)-2 and VEGFR-3 tyrosine kinases. This study assessed the activity of cediranib against the VEGFR-1 tyrosine kinase and the platelet-derived growth factor receptor (PDGFR)-associated kinases c-Kit, PDGFR-α, and PDGFR-ß. Cediranib inhibited VEGF-A-stimulated VEGFR-1 activation in AG1-G1-Flt1 cells (IC(50) = 1.2 nmol/L). VEGF-A induced greatest phosphorylation of VEGFR-1 at tyrosine residues Y1048 and Y1053; this was reversed by cediranib. Potency against VEGFR-1 was comparable with that previously observed versus VEGFR-2 and VEGFR-3. Cediranib also showed significant activity against wild-type c-Kit in cellular phosphorylation assays (IC(50) = 1-3 nmol/L) and in a stem cell factor-induced proliferation assay (IC(50) = 13 nmol/L). Furthermore, phosphorylation of wild-type c-Kit in NCI-H526 tumor xenografts was reduced markedly following oral administration of cediranib (≥1.5 mg/kg/d) to tumor-bearing nude mice. The activity of cediranib against PDGFR-ß and PDGFR-α was studied in tumor cell lines, vascular smooth muscle cells (VSMC), and a fibroblast line using PDGF-AA and PDGF-BB ligands. Both receptor phosphorylation (IC(50) = 12-32 nmol/L) and PDGF-BB-stimulated cellular proliferation (IC(50) = 32 nmol/L in human VSMCs; 64 nmol/L in osteosarcoma cells) were inhibited. In vivo, ligand-induced PDGFR-ß phosphorylation in murine lung tissue was inhibited by 55% following treatment with cediranib at 6 mg/kg but not at 3 mg/kg or less. In contrast, in C6 rat glial tumor xenografts in mice, ligand-induced phosphorylation of both PDGFR-α and PDGFR-ß was reduced by 46% to 61% with 0.75 mg/kg cediranib. Additional selectivity was showed versus Flt-3, CSF-1R, EGFR, FGFR1, and FGFR4. Collectively, these data indicate that cediranib is a potent pan-VEGFR kinase inhibitor with similar activity against c-Kit but is significantly less potent than PDGFR-α and PDGFR-ß.
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Inhibidores de Proteínas Quinasas/farmacología , Quinazolinas/farmacología , Receptores del Factor de Crecimiento Derivado de Plaquetas/antagonistas & inhibidores , Receptores de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Animales , Células COS , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Chlorocebus aethiops , Células HEK293 , Humanos , Ligandos , Pulmón/efectos de los fármacos , Ratones , Ratones Desnudos , Células 3T3 NIH , Fosforilación/efectos de los fármacos , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Inhibidores de Proteínas Quinasas/química , Proteínas Proto-Oncogénicas c-kit/antagonistas & inhibidores , Quinazolinas/química , Ratas , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Transducción de Señal/efectos de los fármacos , Factor de Células Madre/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto , Tirosina Quinasa 3 Similar a fms/antagonistas & inhibidoresRESUMEN
Endometriosis is the growth of endometrial tissue outside of the uterine cavity. Its aetiology remains obscure, and it is difficult to diagnose ranging from asymptomatic to debilitating disease. Mid-infrared (IR) spectroscopy has become recognised as a potential clinical diagnostic tool. Biomolecules absorb mid-IR (4000 cm(-1) to 400 cm(-1)) and from this, a biochemical-cell fingerprint in the form of an absorbance spectrum can be derived. We set out to determine if IR spectroscopy could be used to identify underlying biochemical differences between endometrial tissues growing outside of the uterus (ectopic) from endometrial tissue of the uterus (eutopic). For comparative purposes, endometrial tissues from endometriosis-free women were also obtained (benign eutopic). Attenuated total reflection Fourier-transform IR (ATR-FTIR) spectroscopy or transmission FTIR microspectroscopy was employed for spectral acquisition. Principal component analysis (PCA)-linear discriminant analysis (LDA) was used for chemometric analysis. A clear segregation was exhibited between the three categories independent of inter-individual confounding differences. Importantly, there was a marked difference between eutopic endometrial tissue from patients with or without endometriosis. This indicates that IR spectroscopy coupled with multivariate analysis (e.g., PCA-LDA) may provide a non-invasive diagnostic tool for endometriosis. By analysing the underlying biochemistry of these endometrial tissues, this approach may facilitate a better understanding of this pathology.
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Endometriosis/diagnóstico , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Enfermedades Uterinas/diagnóstico , Análisis Discriminante , Femenino , Humanos , Análisis de Componente PrincipalRESUMEN
Susceptibility to prostate or endometrial cancer is linked with obesity, a state of oestrogen excess. Oestrogen receptor (ER) splice variants may be responsible for the tissue-level of ER activity. Such micro-environmental regulation may modulate cancer initiation and/or progression mechanisms. Real-time reverse transcriptase (RT) polymerase chain reaction (PCR) was used to quantitatively assess the levels of four ER splice variants (ERαΔ3, ERαΔ5, ERß2 and ERß5), plus the full-length parent isoforms ERα and ERß1, in high-risk [tumour-adjacent prostate (n = 10) or endometrial cancer (n = 9)] vs. low-risk [benign prostate (n = 12) or endometrium (n = 9)], as well as a comparison of UK (n = 12) vs. Indian (n = 15) benign prostate. All three tissue groups expressed the ER splice variants at similar levels, apart from ERαΔ5. This splice variant was markedly raised in all of the tumour-adjacent prostate samples compared to benign tissues. Immunofluorescence analysis for ERß2 in prostate tissue demonstrated that such splice variants are present in comparable, if not greater, amounts as the parent full-length isoform. This small pilot study demonstrates the ubiquitous nature of ER splice variants in these tissue sites and suggests that ERαΔ5 may be involved in progression of prostate adenocarcinoma.
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Neoplasias Endometriales/genética , Endometrio/metabolismo , Receptor alfa de Estrógeno/genética , Neoplasias Hormono-Dependientes/genética , Próstata/metabolismo , Neoplasias de la Próstata/genética , Empalme del ARN , Secuencia de Bases , Cartilla de ADN , ADN Complementario , Femenino , Humanos , Masculino , Microscopía Fluorescente , Reacción en Cadena de la Polimerasa de Transcriptasa InversaRESUMEN
The full-length oestrogen receptor (ER) exists in most vertebrates as two separately encoded isoforms. ER splice variants represent truncated or otherwise modified versions of the full-length alpha or beta isoforms of the parent receptor. ERalpha is found on chromosome 6q and encodes a 595 amino acid protein, while ERbeta is found on chromosome 14q and encodes a 530 amino acid protein. These receptors possess differing ligand affinities, are differentially expressed in a tissue-specific fashion and may act antagonistically. Their altered expression has been implicated in the pathophysiology of a diverse range of conditions from cancer progression in hormone-responsive tissues to neurodegenerative disease. Variously co-expressed with full-length ERs, ER splice variants may have a positive or negative influence on transcription either by modifying the effect of the parent receptor or through their own intrinsic activity. To date, the vast majority of studies have used generic primers or antibodies against the full-length receptors and would not distinguish ER-mediated effects associated with various splice variants. Thus the evidence base of the influence of ER splice variants in normal developmental physiology and in the pathogenesis of disease is weak and greater understanding of their role will undoubtedly lead to new therapeutic strategies for disease intervention and treatment. This review aims to compile the current evidence for the presence of ER splice variants in humans, their physiological roles and clinical sequelae.
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Receptor alfa de Estrógeno/metabolismo , Receptor beta de Estrógeno/metabolismo , Neoplasias/metabolismo , Transducción de Señal , Receptor alfa de Estrógeno/genética , Receptor beta de Estrógeno/genética , Medicina Basada en la Evidencia , Femenino , Humanos , Ligandos , Masculino , Neoplasias/genética , Neoplasias/patología , Isoformas de ProteínasRESUMEN
Endometriosis is a debilitating disease in which apoptotic, genetic, immunological, angiogenic and environmental factors have been implicated. Endocrine-disrupting agents (e.g. dioxins) might be involved. Dioxins, via the arylhydrocarbon receptor (AhR), induce estrogen-metabolizing enzymes CYP1A1 and CYP1B1. Elevated expression of gamma-SYNUCLEIN (gamma-SYN) has been associated with hormone-related conditions. Tissue sets consisting of eutopic and ectopic (ovarian) endometrium from patients with stage 3 or 4 endometriosis were obtained. Following RNA extraction and reverse transcription, quantitative real-time reverse transcriptase-polymerase chain reaction was performed for anti-apoptotic B-cell leukaemia/lymphoma 2 (BCL-2), CYP1A1, CYP1B1, estrogen receptor (ER)alpha, ER beta and gamma-SYN. Immunohistochemical analyses for gamma-syn, ER alpha, ER beta and CYP1A1 were also conducted. A 3-9-fold increase in intra-individual expression of CYP1A1 in ectopic (ovarian) endometrium compared with eutopic tissue was observed; immunohistochemical analyses pointed to CYP1A1 being localized to the glandular epithelium. This intra-individual expression profile was not observed for CYP1B1 or BCL-2. However, a 5-53-fold intra-individual increase in gamma-SYN expression was also demonstrated in six of nine tissue sets (a further two showed an increase that was not considered significant) when comparing ectopic to eutopic endometrium; gamma-syn positivity was associated with endothelial cells. An elevation in ER beta was also noted when comparing ectopic to eutopic endometrium; with regard to ER alpha, this was inconsistent. These results suggest an up-regulation of dioxin-inducible CYP1A1 and gamma-SYN occurs in endometriosis. Whether gamma-syn may be a novel diagnostic marker for endometriosis remains to be ascertained.
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Citocromo P-450 CYP1A1/metabolismo , Endometriosis/metabolismo , Endometrio/metabolismo , Regulación de la Expresión Génica/genética , gamma-Sinucleína/metabolismo , Adulto , Hidrocarburo de Aril Hidroxilasas , Citocromo P-450 CYP1A1/genética , Citocromo P-450 CYP1B1 , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Endometriosis/genética , Endometriosis/patología , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad , Fenotipo , Proteínas Proto-Oncogénicas c-bcl-2/genética , gamma-Sinucleína/genéticaRESUMEN
Inhibition of vascular endothelial growth factor-A (VEGF) signaling is a promising therapeutic approach that aims to stabilize the progression of solid malignancies by abrogating tumor-induced angiogenesis. This may be accomplished by inhibiting the kinase activity of VEGF receptor-2 (KDR), which has a key role in mediating VEGF-induced responses. The novel indole-ether quinazoline AZD2171 is a highly potent (IC50 < 1 nmol/L) ATP-competitive inhibitor of recombinant KDR tyrosine kinase in vitro. Concordant with this activity, in human umbilical vein endothelial cells, AZD2171 inhibited VEGF-stimulated proliferation and KDR phosphorylation with IC50 values of 0.4 and 0.5 nmol/L, respectively. In a fibroblast/endothelial cell coculture model of vessel sprouting, AZD2171 also reduced vessel area, length, and branching at subnanomolar concentrations. Once-daily oral administration of AZD2171 ablated experimental (VEGF-induced) angiogenesis in vivo and inhibited endochondral ossification in bone or corpora luteal development in ovary; physiologic processes that are highly dependent upon neovascularization. The growth of established human tumor xenografts (colon, lung, prostate, breast, and ovary) in athymic mice was inhibited dose-dependently by AZD2171, with chronic administration of 1.5 mg per kg per day producing statistically significant inhibition in all models. A histologic analysis of Calu-6 lung tumors treated with AZD2171 revealed a reduction in microvessel density within 52 hours that became progressively greater with the duration of treatment. These changes are indicative of vascular regression within tumors. Collectively, the data obtained with AZD2171 are consistent with potent inhibition of VEGF signaling, angiogenesis, neovascular survival, and tumor growth. AZD2171 is being developed clinically as a once-daily oral therapy for the treatment of cancer.