Aurora kinase inhibitors: a new class of drugs targeting the regulatory mitotic system

The present review gives a perspective on the Aurora kinase family members, their function in normal cells, their role in cancer progression as well as their potential as target for anticancer treatment. Mitosis has been an important target for anticancer therapy development, leading to some specific drugs mainly addressing Tubulines, as a key structure of the mitotic spindle. Vinca alkaloids, taxanes or epotilones are good examples of conventionally developed antimitotic agents. However, novel classes of antineoplastic drugs are being studied, targeting the regulatory system that controls functional aspects of mitosis, such as Aurora or Polo-like kinases or Kinespondin inhibitors. The specific role of the different Aurora kinase proteins as regulator enzymes of the mitotic process in normal cells is discussed. Some of the mechanisms that link Aurora overexpression with cancer are also considered. Thereafter, the clinical and preclinical development of the different Aurora kinase inhibitors is presented. This is nowadays a very active area of therapeutic research and at least, sixteen new compounds are being studied as potential antineoplastic drugs. Most of them are in a very early phase of clinical development. However, we summarized the most recently published findings related with these drugs: main characteristics, way of administration, dose limiting toxicities and recommended doses for further studies. Another important aspect in Aurora kinase inhibition is the study and validation of potential biomarkers to optimize the clinical development. Several studies included pharmacodynamic assessments in normal blood cells, skin or/and tumor biopsies. Several proposals included a higher mitotic index, a decreased number of mitosis with bipolar spindles or normal alignment of chromosomes and inhibition of histone H3 phosphorylation. Future strategies and challenges for trials with Aurora kinase inhibitors are also discussed.     

Human papillomaviruses are identified in a subgroup of sinonasal squamous cell carcinomas with favorable outcome

BACKGROUND:

The role of human papillomavirus (HPV) in the pathogenesis of squamous cell carcinomas (SCCs) of the sinonasal tract and its clinicopathological implications were evaluated.

METHODS:

All SCCs of the sinonasal tract diagnosed in the Hospital Clinic of Barcelona from 1981 to 2006 were retrospectively evaluated (N = 60). Clinical and pathological data were reviewed. HPV infection was determined and typed by amplification of HPV DNA by polymerase chain reaction using the SPF‐10 primers. p16^INK4a expression was determined by immunohistochemistry. Overall and progression‐free survival for HPV‐positive and ‐negative patients was estimated by Kaplan‐Meier analysis and by the use of a multivariate Cox proportional hazards model.

RESULTS:

HPV DNA was detected in tumor tissue of 12 of 60 (20%) patients. HPV16 was identified in 11 tumors and HPV35 in 1. Immunohistochemistry for p16^INK4a stained all HPV‐positive and no HPV‐negative tumors (P < .001). No differences were observed in terms of site and histological grade or stage at presentation between HPV‐positive and ‐negative tumors. However, HPV‐positive patients had a significantly better 5‐year progression‐free survival (62%; 95% confidence interval [CI], 23%‐86% vs 20%; 95% CI, 9%‐34%; P = .0043, log‐rank test) and overall survival (80%; 95% CI, 20%‐96% vs 31%; 95% CI, 15%‐47%; P = .036, log‐rank test) than patients with HPV‐negative tumors. In multivariate analysis, HPV‐positive tumors were associated with improved progression‐free survival (hazard ratio, 0.21; 95% CI, 0.17‐0.98; P = .012).

CONCLUSIONS:

A subgroup of sinonasal SCCs is associated with HPV infection. These tumors have a significantly better prognosis. Cancer 2009. © 2009 American Cancer Society.     

FLIP regulation of HO-1 and TNF signalling in human acute myeloid leukemia provides a unique secondary anti-apoptotic mechanism

Acute myeloid leukemia (AML) comprises a heterogeneous group of clonal disorders of hematopoietic progenitors. We previously showed that heme oxygenase-1 (HO-1/Hsp32) underlies resistance of AML to TNF-induced apoptosis. Here we show for the first time that the modulatory protein, FLICE-inhibitory protein (FLIP) indirectly regulates induction of HO-1 in response to TNF in human AML blasts, but not non-cancerous control cells. In AML cells, TNF-induced FLIP expression was an NF-κB-dependent event, and silencing of FLIP isoforms (FLIPL, FLIPS and FLIPR) induced pro-apoptotic responses to TNF, with FLIPL knock-down providing the greatest apoptotic switch. However, FLIPL knock-down consequently increased expression of HO-1; a response that occurred in AML (but not non-cancerous) cells to protect a proportion of them from apoptotic death. Our results show that increases in HO-1 induced an apoptotic-resistant form in AML cells in the absence of FLIPL. This is the first time that FLIPL has been shown to regulate the expression of HO-1. These data reveal unique regulatory networks in cancerous AML cells whereby FLIP regulation of HO-1 provides AML cells with secondary anti-apoptotic protection against extrinsic factors (eg TNF/chemotherapies) that try to switch on death signals in these highly death-resistant cells. Future AML therapies should target these mechanisms.     

Metabolic markers in blood can separate prostate cancer from benign prostatic hyperplasia

Background:

An individualised risk-stratified screening for prostate cancer (PCa) would select the patients who will benefit from further investigations as well as therapy. Current detection methods suffer from low sensitivity and specificity, especially for separating PCa from benign prostatic conditions. We have investigated the use of metabolomics analyses of blood samples for separating PCa patients and controls with benign prostatic hyperplasia (BPH).

Methods:

Blood plasma and serum samples from 29 PCa patient and 21 controls with BPH were analysed by metabolomics analysis using magnetic resonance spectroscopy, mass spectrometry and gas chromatography. Differences in blood metabolic patterns were examined by multivariate and univariate statistics.

Results:

By combining results from different methodological platforms, PCa patients and controls were separated with a sensitivity and specificity of 81.5% and 75.2%, respectively.

Conclusions:

The combined analysis of serum and plasma samples by different metabolomics measurement techniques gave successful discrimination of PCa and controls, and provided metabolic markers and insight into the processes characteristic of PCa. Our results suggest changes in fatty acid (acylcarnitines), choline (glycerophospholipids) and amino acid metabolism (arginine) as markers for PCa compared with BPH.     

Immunomodulatory effects of aqueous and organic fractions from Petiveria alliacea on human dendritic cells

Petiveria alliacea is a plant traditionally known for its anti-inflammatory and anti-tumor activities; however, the molecular and cellular mechanisms of its immunomodulatory properties are still unknown. Dendritic cells (DC) promote adaptive immune response by activating T lymphocytes, inducing an effector response or tolerance depending on the DC differentiation level. Herein, we evaluated the immunomodulatory activity of aqueous and organic plant fractions from P. alliacea using human monocyte-derived dendritic cells. The phenotype, cytokine secretion and gene expression were estimated after treatment with the plant fractions. We found that P. alliacea aqueous fraction induced morphological changes and co-stimulatory expression of CD86, indicating partial DC maturation. In addition, pro-inflammatory cytokines such as IL-1β, IL-6, IL-8, IL-10, IL-12p70, and TNF-α were secreted. The fraction also increased NF-κB gene expression while down-regulating TGFβ gene expression. These results suggest that the aqueous fraction can induce partial DC activation, a situation that can be relevant in tolerance induction. It is important to state that the organic fraction by itself does not show any immunomodulatory activity. This study provides evidence for possible immunomodulatory activity of P. alliacea extracts which has been used in traditional medicine in Colombia.     

Lipschütz [corrected] ulcers--four cases

Abstract:  A distinctive clinical entity of acute genital ulcers occurring in adolescents, with nonvenereal infectious etiology was described by Lipschütz in 1913. We describe four puberal virgin girls who developed fever and painful genital ulcers. The main causes infectious and noninfectious of ulceration were rejected. Although the etiology is unknown, recent cases related with Epstein–Barr virus acute infection have been reported.     

Dermoscopic patterns of benign volar melanocytic lesions in patients with atypical mole syndrome

BACKGROUND: Acral benign melanocytic lesions in white populations, particularly in subjects with atypical mole syndrome, have been poorly characterized until recently. The advent of dermoscopy has enabled more specific diagnoses of these pigmented skin lesions. OBJECTIVE: To evaluate the clinical and dermoscopic features of benign volar lesions in a group of white patients with atypical mole syndrome. SETTING: A private medical center specializing in early diagnosis of malignant melanoma and a melanoma unit in a university hospital. METHODS: Acral melanocytic lesions in 511 patients with atypical mole syndrome were studied using standard clinical assessment and dermoscopy. RESULTS: Two hundred ten acral melanocytic lesions were observed in 156 of the patients: 165 lesions were present on the soles of 121 patients and 45 lesions on the palms of 35 patients. No acral malignant lesions were detected. We observed the following patterns of lesions: parallel furrow in 111 lesions (52.9%), latticelike in 26 lesions (12.4%), fibrillar or filamentous in 13 lesions (6.2%), and nontypical in 29 lesions (13.8%). In 31 lesions (14.8%), we observed 3 previously undefined patterns: a globular pattern in 11 lesions (5.2%), a homogeneous pattern in 15 lesions (7.1%), and an acral reticular pattern in 5 lesions (2.4%). CONCLUSIONS: We observed a greater number of benign melanocytic lesions in glabrous skin than expected, probably related to our cohort selection of patients with atypical mole syndrome, although the lesions generally exhibited patterns on dermoscopy similar to those seen in Japanese studies. We defined 3 new benign dermoscopic patterns, which will enable better characterization of acral lesions.     

Dendritic cells in pigmented basal cell carcinoma: a relevant finding by reflectance-mode confocal microscopy

BACKGROUND: Reflectance-mode confocal microscopy (RCM) is a new approach for the in vivo diagnosis of skin tumors. A few studies of RCM on basal cell carcinoma (BCC) have provided specific diagnostic criteria, but large studies on pigmented basal cell carcinoma are lacking. Proliferation of large dendritic-shaped cells within a melanocytic tumor has been associated with the diagnosis of melanoma by RCM. Benign melanocytes and Langerhans cells may populate BCC according to previous histological studies. We studied 3 consecutive pigmented BCC by means of RCM and performed a histological and immunohistochemical correlation focusing on the presence of dendritic structures. OBSERVATIONS: Reflectance-mode confocal microscopy revealed highly refractive dendritic structures within tumor nests that correlated with the presence of melanocytes within the tumor by immunochemical analysis. In 1 case, dendritic structures on the overlying epidermis corresponding to Langerhans cells were also noted. Leaf-like areas observed on dermoscopy correlated with low-refractive cordlike structures and nodules by RCM and corresponded to nests of basaloid cells, whereas blue-gray globules presented as bright oval structures with ill-defined borders corresponding to melanophages. CONCLUSIONS: Reflectance-mode confocal microscopy allows the study of pigmented BCC and the identification of specific criteria described previously. In these tumors, dendritic melanocytes can be easily identified with this technique.     

Giant skin tags: report of two cases

Skin tags are skin-colored, pedunculated tumors with a smooth surface. Histologically are composed by loose collagen fibers and dilated capillaries. Giant skin tags are reported rarely in the literature. We present the case of two giant skin tags on labium majus. To our knowledge, these are the largest skin tags reported.