Biomarker Commons

Filamin-A as a marker and target for DNA damage based cancer therapy.

DNA Repair (Amst). 2012 Feb 1;11(2):192-200

Authors: Yue J, Lu H, Liu J, Berwick M, Shen Z

Abstract
Filamin-A, also called actin binding protein 280 (ABP-280), cross-links the actin filaments into dynamic orthogonal network to serve as scaffolds in multiple signaling pathways. It has been reported that filamin-A interacts with DNA damage response proteins BRCA1 and BRCA2. Defects of filamin-A impair the repair of DNA double strand breaks (DSBs), resulting in sensitization of cells to ionizing radiation. In this study, we sought to test the hypothesis that filamin-A can be used as a target for cancer chemotherapy and as a biomarker to predict cancer response to therapeutic DNA damage. We found that reduction of filamin-A sensitizes cancer cells to chemotherapy reagents bleomycin and cisplatin, delays the repair of not only DSBs but also single strand breaks (SSBs) and interstrand crosslinks (ICLs), and increases chromosome breaks after the drug treatment. By treating a panel of human melanoma cell lines with variable filamin-A expression, we observed a correlation between expression level of filamin-A protein and drug IC(50). We further inhibited the expression of filamin-A in melanoma cells, and found that this confers an increased sensitivity to bleomycin and cisplatin treatment in a mouse xenograft tumor model. These results suggest that filamin-A plays a role in repair of a variety of DNA damage, that lack of filamin-A is a prognostic marker for a better outcome after DNA damage based treatment, and filamin-A can be inhibited to sensitize filamin-A positive cancer cells to therapeutic DNA damage. Thus filamin-A can be used as a biomarker and a target for DNA damage based cancer therapy.

PMID: 22051193 [PubMed - indexed for MEDLINE]

CEACAM1 in malignant melanoma: a diagnostic and therapeutic target.

Curr Top Med Chem. 2012;12(1):3-10

Authors: Sapoznik S, Ortenberg R, Schachter J, Markel G

Abstract
CEACAM1 adhesion molecule is broadly expressed, participates in pivotal cellular and immunological processes and is involved in cancer. Originally identified as a tumor suppressor, it is now known that in several cancers, including malignant melanoma, CEACAM1 expression correlates with tumor progression and poor survival. Here we review the findings connecting CEACAM1 to malignant melanoma, encompassing in-vitro, in-vivo and patients-derived data. A CEACAM1-mediated mechanism used by melanoma cells to evade immune attack is described in detail. Finally, the potential value of CEACAM1 as a melanoma biomarker and therapeutic target is being discussed.

PMID: 22196267 [PubMed - indexed for MEDLINE]

E2F1-dependent oncogenic addiction of melanoma cells to MDM2.

Oncogene. 2012 Feb 16;31(7):828-41

Authors: Verhaegen M, Checinska A, Riblett MB, Wang S, Soengas MS

Abstract
One of the defining features of aggressive melanomas is their complexity. Hundreds of mutations and an ever increasing list of changes in the transcriptome and proteome distinguish normal from malignant melanocytic cells. Yet, despite this altered genetic background, a long-known attribute of melanomas is a relatively low rate of mutations in the p53 gene. However, it is unclear whether p53 is maintained in melanoma cells because it is required for their survival, or because it is functionally disabled. More pressing from a translational perspective, is to define whether there is a tumor cell-selective wiring of p53 that offers a window for therapeutic intervention. Here, we provide genetic and pharmacological evidence demonstrating that p53 represents a liability to melanoma cells, which they thwart by assuming an oncogenic dependency on the E3 ligase murine double minute-2 (MDM2). Specifically, we used a combination of RNA interference and two structurally independent small molecule inhibitors of the p53-MDM2 interaction to assess the relative requirement of both proteins for the viability of normal melanocytes and a broad panel of melanoma cell lines. We demonstrated in vitro and in vivo that MDM2 is selectively required to blunt latent pro-senescence signals in melanoma cells. Notably, the outcome of MDM2 inactivation depends not only on the mutational status of p53, but also on its ability to signal to the transcription factor E2F1. These data support MDM2 as a drug target in melanoma cells, and identify E2F1 as a biomarker to consider when stratifying putative candidates for clinical studies of p53-MDM2 inhibitors.

PMID: 21743494 [PubMed - indexed for MEDLINE]

PD-1 blockade augments Th1 and Th17 and suppresses Th2 responses in peripheral blood from patients with prostate and advanced melanoma cancer.

J Immunother. 2012 Feb-Mar;35(2):169-78

Authors: Dulos J, Carven GJ, van Boxtel SJ, Evers S, Driessen-Engels LJ, Hobo W, Gorecka MA, de Haan AF, Mulders P, Punt CJ, Jacobs JF, Schalken JA, Oosterwijk E, van Eenennaam H, Boots AM

Abstract
Negative costimulation on T cells is exploited by both prostate cancer and melanoma to evade antitumor immunity. Blocking such mechanisms restores antitumor immunity as was demonstrated by the improved survival of patients with metastatic melanoma after treatment with an antibody blocking the CTLA-4 inhibitory receptor (ipilimumab). Enhanced expression of another inhibitory immunoreceptor, programmed death-1 (PD-1), and its ligand, PD-L1, was found to correlate with a poor prognosis in prostate cancer and melanoma. PD-1-blocking antibodies are being developed to modulate antitumor immune responses. To support preclinical and clinical development of anti-PD-1 therapy, we sought to develop biomarker assays that can detect the effect of PD-1-blocking agents in whole blood and peripheral blood mononuclear cells. In this study, we assessed the effect of PD-1 blockade in modulating super antigen (staphylococcus enterotoxin B)-induced and recall antigen (tetanus toxoid)-induced T-cell reactivity in vitro using whole blood and peripheral blood mononuclear cells from patients with advanced melanoma, prostate cancer, and healthy controls. PD-1 blockade was found to shift antigen-induced cellular reactivity toward a proinflammatory Th1/Th17 response, as evidenced by enhanced production of interferon γ, interleukin (IL)-2, tumor necrosis factor α, IL-6, and IL-17 and reduced production of the Th2 cytokines IL-5 and IL-13. It is interesting to note that suppression of Th2 responsivity was seen with whole blood cells only from patients with cancer. Taken together, we identified novel biomarker assays that might be used to determine the functional consequences of PD-1 blockade in peripheral blood cells from patients with cancer. How these assays translate to the local antitumor response remains to be established in a clinical setting.

PMID: 22306905 [PubMed - indexed for MEDLINE]

The current status of S-100B as a biomarker in melanoma.

Eur J Surg Oncol. 2012 Apr;38(4):281-5

Authors: Kruijff S, Hoekstra HJ

Abstract
Melanoma is the most malignant type of all skin cancer types. It causes over 75% of all skin cancer related mortality. In the Netherlands, the total number of new diagnosed melanoma patients is expected to increase from 2400 patients in 2000 to 4800 patients in 2015. After surgical treatment, 20-28% of melanoma patients present with loco-regional recurrence, 26-60% with regional recurrences, and 15-50% with distant metastases. Early detection of lymph node (micro) metastases by means of a sentinel lymph node biopsy (SLNB) is therefore of crucial importance since early lymph node dissection decrease treatment morbidity and improve overall survival. However when patients present with palpable nodes, given the heterogeneity in survival, the suspicion rises that numerous patients have a form of subclinical dissemination, which can remain undetected by current modern imaging methods. Biomarkers could illuminate on this matter, although there is very little understanding of their biological significance. It can be expected that the strongest biological markers are surrogates of key biological events. The protein S-100B seems to be the best analyzed biomarker in melanoma. It has the potential to identify high-risk stage III melanoma patients who may benefit from adjuvant systematic treatment. In the stratification of new adjuvant therapeutic trials in patients with loco-regional recurrences, we therefore recommend the use of S-100B in the stratification. Since an effective (adjuvant) therapy for loco-regional metastatic and disseminated melanoma is recently introduced, the use of S-100B seems to alter dramatically in the near future.

PMID: 22240030 [PubMed - indexed for MEDLINE]

Pitfalls in retrospective analyses of biomarkers: a case study with metastatic melanoma patients.

J Immunol Methods. 2012 Feb 28;376(1-2):108-12

Authors: Potter DM, Butterfield LH, Divito SJ, Sander CA, Kirkwood JM

Abstract
BACKGROUND: Reliable prognostic biomarkers of survival and response to treatment are clearly important in oncology, and many studies have been carried out with the objective of identifying new prognostic biomarkers. Retrospective analysis of blood banked from patients is a frequently used paradigm for these studies. We describe a new study of the association of serum biomarker level with overall survival in melanoma patients, and the problems encountered in carrying it out.
METHODS: Blood samples from 56 patients with stage IV metastatic melanoma were drawn prior to initiation of any treatment for their disease. Sera from the samples were stored for up to 94 months at -80°C, and were subsequently thawed at the same time and tested by multiplex Luminex assay for 30 analytes (cytokines, chemokines and growth factors). Cox regression analysis was used to assess the association between these analytes and time-to-death.
RESULTS: Of the 30 analytes, 17 were associated with survival, most strongly so, and in all cases, a higher analyte level was associated with increased survival. In addition, the correlations of the levels of all possible pairs of analytes were all positive and in almost all cases highly significant. However, these results are artifacts that arise from the combination of two peculiarities of the data: the apparent decrease in analyte level with storage time, and the uniformly shorter storage times of the samples from censored patients than the storage times of the samples from patients who died.
CONCLUSIONS: All retrospective studies can have hidden biases, and thus investigators should not claim new findings before examining the data in detail with the goal of determining whether the findings could be spurious. There were several suspicious findings in our initial analyses: too many analytes found significant, too many very small p-values, a uniformly positive association of analyte level with survival, and a uniformly positive correlation between analyte levels. We were convinced that these findings must be artifacts, and further analyses showed that the findings could be explained by an apparent decrease of analyte level storage time.

PMID: 22210094 [PubMed - indexed for MEDLINE]

Neuropilin-2: a novel biomarker for malignant melanoma?

Hum Pathol. 2012 Mar;43(3):381-9

Authors: Rushing EC, Stine MJ, Hahn SJ, Shea S, Eller MS, Naif A, Khanna S, Westra WH, Jungbluth AA, Busam KJ, Mahalingam M, Alani RM

Abstract
Neuropilin-2, a cell surface receptor involved in angiogenesis and axonal guidance, has recently been shown to be a critical mediator of tumor-associated lymphangiogenesis. Given that lymphangiogenesis is a major conduit of metastasis in melanomas and that blocking neuropilin-2 function in vivo is effective in inhibiting tumor cell metastasis, we sought to determine the clinical relevance of neuropilin-2 expression in cutaneous melanoma. Immunohistochemical analysis of neuropilin-2 expression was evaluated in nevomelanocytic proliferations that included a tissue microarray and histologic sections from samples of primary melanomas (n = 42; 40 for tissue microarray, 2 for histologic sections), metastatic melanomas (n = 30; 22 for tissue microarray, 8 for histologic sections), and nevi (n = 30; 5 for tissue microarray, 25 for histologic sections), as well as a panel of normal human tissues and select nonmelanocytic tumors. Staining for grading and intensity of neuropilin-2 expression was estimated semiquantitatively as follows for the former: less than 20%, 20% to 60%, and more than 60% of tissue present, and for the latter from 0 to 3, with 3 being the highest and 0 the lowest intensity. In nevomelanocytic proliferations, more than 20% staining for neuropilin-2 was noted in 36 (86%) of 42 cases of primary melanoma, in 27 (90%) of 30 cases of metastatic melanoma, and in 9 (30%) of 30 cases of nevi with differences achieving statistical significance between melanoma (primary and metastatic) and nevi (P < .0001). For staining intensity, an intensity of 2 or more was noted in 36 (86%) of 42 cases of primary melanoma, in 17 (57%) of 30 cases of metastatic melanoma and in 7 (30%) of 23 cases of nevi, with differences achieving statistical significance between melanoma (primary and metastatic) and nevi (P < .0001). In normal human tissue, consistently strong neuropilin-2 staining was noted in kidney (glomerular endothelial cells, collecting tubules, and collecting ducts), skin (epidermal keratinocytes), and testes (epithelium of the seminiferous tubules), whereas in tumoral tissue, consistently strong staining was noted only in renal cell carcinoma but not in any of the other tumors studied. More recently, using a heterotypic coculture methodology with melanoma and endothelial cells, we have demonstrated successful up-regulation of neuropilin-2 and confirmed the critical role of neuropilin-2 in melanoma-endothelial interactions. Because these coculture methods were developed to model melanoma metastasis, the significantly increased and enhanced expression of neuropilin-2 staining in primary and metastatic melanoma versus nevi in the current study suggests that it is also relevant in vivo.

PMID: 21840568 [PubMed - indexed for MEDLINE]

Chondroitin sulfate proteoglycan-4: a biomarker and a potential immunotherapeutic target for canine malignant melanoma.

Vet J. 2011 Nov;190(2):e26-30

Authors: Mayayo SL, Prestigio S, Maniscalco L, La Rosa G, Aricò A, De Maria R, Cavallo F, Ferrone S, Buracco P, Iussich S

Abstract
Chondroitin sulfate proteoglycan-4 (CSPG4), also known as high molecular weight-melanoma associated antigen (HMW-MAA), is a membrane-bound chondroitin sulfate proteoglycan highly expressed by human melanoma cells. This phylogenetically conserved tumour antigen plays an important biological role in human melanoma, where it is used as a marker to diagnose forms with unusual characteristics, such as desmoplastic melanoma, and to detect melanoma cells in lymph nodes and peripheral blood, and as a target for immunotherapy because of its restricted distribution in normal tissues. To identify suitable targets to develop novel approaches of treating canine melanoma, CSPG4 was studies to see whether it is expressed in canine malignant melanomas. Immunohistochemical staining of 65 canine malignant melanomas with an anti-human CSPG4-specific antibody detected CSPG4 in 37 cases (56.9%). Positive staining was more frequent, albeit not significantly, in amelanotic compared to melanotic tumours and was statistically associated with tumours having both melanin and the epithelioid histotype. The frequency of CSPG4 expression was similar to that of other melanoma antigens used as diagnostic markers for canine malignant melanoma, such as Melan A and the protein recognized by the PNL2 monoclonal antibody. The results suggest that CSPG4 constitutes a new potential immunohistochemical marker of canine malignant melanoma and may represent an immunotherapeutic target as in humans.

PMID: 21482159 [PubMed - indexed for MEDLINE]

Assessment of prognostic circulating tumor cells in a phase III trial of adjuvant immunotherapy after complete resection of stage IV melanoma.

Ann Surg. 2012 Feb;255(2):357-62

Authors: Hoshimoto S, Faries MB, Morton DL, Shingai T, Kuo C, Wang HJ, Elashoff R, Mozzillo N, Kelley MC, Thompson JF, Lee JE, Hoon DS

Abstract
OBJECTIVE: To verify circulating tumor cell (CTC) prognostic utility in stage IV resected melanoma patients in a prospective international phase III clinical trial.
BACKGROUND: Our studies of melanoma patients in phase II clinical trials demonstrated prognostic significance for CTCs in patients with AJCC stage IV melanoma. CTCs were assessed to determine prognostic utility in follow-up of disease-free stage IV patients pre- and during treatment.
METHODS: After complete metastasectomy, patients were prospectively enrolled in a randomized trial of adjuvant therapy with a whole-cell melanoma vaccine, Canvaxin, plus Bacille Calmette-Guerin (BCG) versus placebo plus BCG. Blood specimens obtained pretreatment (n = 244) and during treatment (n = 214) were evaluated by quantitative real-time reverse-transcriptase polymerase chain reaction (qPCR) for expression of MART-1, MAGE-A3, and PAX3 mRNA biomarkers. Univariate and multivariate Cox analyses examined CTC biomarker expression with respect to clinicopathological variables.
RESULTS: CTC biomarker(s) (≥ 1) was detected in 54% of patients pretreatment and in 86% of patients over the first 3 months. With a median follow-up of 21.9 months, 71% of patients recurred and 48% expired. CTC levels were not associated with known prognostic factors or treatment arm. In multivariate analysis, pretreatment CTC (> 0 vs. 0 biomarker) status was significantly associated with disease-free survival (DFS; HR 1.64, P = 0.002) and overall survival (OS; HR 1.53, P = 0.028). Serial CTC (>0 vs. 0 biomarker) status was also significantly associated with DFS (HR 1.91, P = 0.02) and OS (HR 2.57, P = 0.012).
CONCLUSION: CTC assessment can provide prognostic discrimination before and during adjuvant treatment for resected stage IV melanoma patients.

PMID: 22202581 [PubMed - indexed for MEDLINE]

A prospective phase II trial exploring the association between tumor microenvironment biomarkers and clinical activity of ipilimumab in advanced melanoma.

J Transl Med. 2011;9:204

Authors: Hamid O, Schmidt H, Nissan A, Ridolfi L, Aamdal S, Hansson J, Guida M, Hyams DM, Gómez H, Bastholt L, Chasalow SD, Berman D

Abstract
BACKGROUND: Ipilimumab, a fully human monoclonal antibody that blocks cytotoxic T-lymphocyte antigen-4, has demonstrated an improvement in overall survival in two phase III trials of patients with advanced melanoma. The primary objective of the current trial was to prospectively explore candidate biomarkers from the tumor microenvironment for associations with clinical response to ipilimumab.
METHODS: In this randomized, double-blind, phase II biomarker study (ClinicalTrials.gov NCT00261365), 82 pretreated or treatment-naïve patients with unresectable stage III/IV melanoma were induced with 3 or 10 mg/kg ipilimumab every 3 weeks for 4 doses; at Week 24, patients could receive maintenance doses every 12 weeks. Efficacy was evaluated per modified World Health Organization response criteria and safety was assessed continuously. Candidate biomarkers were evaluated in tumor biopsies collected pretreatment and 24 to 72 hours after the second ipilimumab dose. Polymorphisms in immune-related genes were also evaluated.
RESULTS: Objective response rate, response patterns, and safety were consistent with previous trials of ipilimumab in melanoma. No associations between genetic polymorphisms and clinical activity were observed. Immunohistochemistry and histology on tumor biopsies revealed significant associations between clinical activity and high baseline expression of FoxP3 (p = 0.014) and indoleamine 2,3-dioxygenase (p = 0.012), and between clinical activity and increase in tumor-infiltrating lymphocytes (TILs) between baseline and 3 weeks after start of treatment (p = 0.005). Microarray analysis of mRNA from tumor samples taken pretreatment and post-treatment demonstrated significant increases in expression of several immune-related genes, and decreases in expression of genes implicated in cancer and melanoma.
CONCLUSIONS: Baseline expression of immune-related tumor biomarkers and a post-treatment increase in TILs may be positively associated with ipilimumab clinical activity. The observed pharmacodynamic changes in gene expression warrant further analysis to determine whether treatment-emergent changes in gene expression may be associated with clinical efficacy. Further studies are required to determine the predictive value of these and other potential biomarkers associated with clinical response to ipilimumab.

PMID: 22123319 [PubMed - indexed for MEDLINE]

Serum DJ-1/PARK 7 is a potential biomarker of choroidal nevi transformation.

Invest Ophthalmol Vis Sci. 2012 Jan;53(1):62-7

Authors: Bande MF, Santiago M, Blanco MJ, Mera P, Capeans C, Rodríguez-Alvarez MX, Pardo M, Piñeiro A

Abstract
PURPOSE: There is substantial evidence that intraocular melanomas arise from benign nevi in the uveal tract. Previous studies performed by the authors revealed that uveal melanoma cells secrete the oncoprotein DJ-1/PARK7 into the extracellular environment and circulation. The aim of this study was to determine whether circulating DJ-1 serum levels correlate with known clinical risk factors of nevi growth.
METHODS: Standardized ultrasonography, optical coherence tomography, and eye fundus examinations were used to evaluate the clinical risk factors of nevi growth. These clinical risk factors (including nevi size, distance of margins to the optic disc, detection of acoustic hollowness, presence of ocular symptoms, orange pigment, subretinal fluid, and absence of drusen) were examined in 53 consecutive patients from January 2009 to February 2011. Serum levels of DJ-1/PARK7 in these patients and in healthy age- and sex-matched controls (n = 32) were analyzed using ELISA.
RESULTS: Within the choroidal nevi group, DJ-1 serum levels were higher in those with symptoms (P < 0.033), with a nevus thickness greater than 1.5 mm (P < 0.001), a large basal diameter greater than 8 mm (P < 0.001), and the presence of acoustic hollowness (P < 0.001), compared to those patients without these risk factors. Similar significant differences were found when these at risk nevi subgroups were compared to healthy persons.
CONCLUSIONS: Elevated serum levels of DJ-1 are associated with choroidal nevi transformation risk factors. Therefore, DJ-1 appears to be a promising factor for predicting the growth of choroidal nevi and may be a potential biomarker of malignancy.

PMID: 22125279 [PubMed - indexed for MEDLINE]

Quantifying histological features of cancer biospecimens for biobanking quality assurance using automated morphometric pattern recognition image analysis algorithms.

J Biomol Tech. 2011 Sep;22(3):108-18

Authors: Webster JD, Simpson ER, Michalowski AM, Hoover SB, Simpson RM

Abstract
Biorepository-supported translational research depends on high-quality, well-annotated specimens. Histopathology assessment contributes insight into how representative lesions are for research objectives. Feasibility of documenting histological proportions of tumor and stroma was studied in an effort to enhance information regarding biorepository tissue heterogeneity. Using commercially available software, unique spatial-spectral algorithms were developed for applying automated pattern recognition morphometric image analysis to quantify histologic tumor and nontumor tissue areas in biospecimen tissue sections. Measurements were acquired successfully for 75/75 (100%) lymphomas, 76/77 (98.7%) osteosarcomas, and 60/70 (85.7%) melanomas. The percentage of tissue area occupied by tumor varied among patients and tumor types and was distributed around medians of 94% [interquartile range (IQR)=14%] for lymphomas, 84% for melanomas (IQR=24%), and 39% for osteosarcomas (IQR=44%). Within-patient comparisons from a subset, including multiple individual patient specimens, revealed ≤12% median coefficient of variation (CV) for lymphomas and melanomas. Phenotypic heterogeneity of osteosarcomas resulted in 33% median CV. Uniformly applied, tumor-specific pattern recognition software permits automated tissue-feature quantification. Furthermore, dispersion analyses of area measurements across collections, as well as of multiple specimens from individual patients, support using limited tissue slices to gauge features for some tumor types. Quantitative image analysis automation is anticipated to minimize variability associated with routine biorepository pathologic evaluations and enhance biomarker discovery by helping to guide the selection of study-appropriate specimens.

PMID: 21966258 [PubMed - indexed for MEDLINE]

Circulating cell-free DNA in plasma of melanoma patients: qualitative and quantitative considerations.

Clin Chim Acta. 2011 Nov 20;412(23-24):2141-5

Authors: Pinzani P, Salvianti F, Zaccara S, Massi D, De Giorgi V, Pazzagli M, Orlando C

Abstract
DNA integrity in blood is an emerging biomarker in cancer. Here we report a real time PCR approach for the absolute quantification of four amplicons of 67, 180, 306 and 476 bp in cutaneous melanoma. Three different integrity indexes (180/67, 306/67 and 476/67 ratios) were tested for their ability to reflect differences in plasma cell-free DNA (cfDNA) fragmentation in 79 patients affected by cutaneous melanoma and 34 healthy subjects. All the three integrity indexes showed higher values in melanoma patients in comparison with healthy subjects. According to ROC curve analysis, the ratio 180/67 is the most suitable index to be used in cancer patient selection, even if the combination of the 3 indexes gives the best performance in terms of clinical sensitivity. The most represented fragments in plasma of melanoma patients are those comprised between 181 and 307 bp, while in healthy subjects there is a prevalence of shorter fragments (67-180 bp). In conclusion, DNA integrity indexes can be considered suitable parameters for monitoring cfDNA fragmentation in melanoma patients.

PMID: 21839068 [PubMed - indexed for MEDLINE]

Prognostic significance of cytoplasmic p27 expression in human melanoma.

Cancer Epidemiol Biomarkers Prev. 2011 Oct;20(10):2212-21

Authors: Chen G, Cheng Y, Zhang Z, Martinka M, Li G

Abstract
BACKGROUND: The cyclin-dependent kinase inhibitor p27 plays important roles in cell proliferation, cell motility, and apoptosis. Interestingly, the nuclear and cytoplasmic p27 exert opposite biological functions. In this study, we investigated the prognostic impact of subcellular p27 expression.
METHODS: We constructed melanoma tissue microarrays in a large series of melanoma patients, including 29 normal nevi, 52 dysplastic nevi, 270 primary melanomas, and 148 metastatic melanomas. The expression level of subcellular p27 in different stages of melanocytic lesions and its prognostic significance were evaluated.
RESULTS: Compared with dysplastic nevi, nuclear p27 expression was remarkably reduced in primary melanomas and further reduced in metastatic melanoma (P < 0.001 for both), whereas cytoplasmic p27 expression is significantly increased from dysplastic nevi to primary melanomas (P = 0.032) and further increased in melanoma metastases (P = 0.037). Although loss of nuclear p27 expression is correlated with a worse 5-year survival of primary melanoma patients in Kaplan-Meier analysis (P = 0.046), it is not a prognostic factor by multivariate Cox regression analysis. On the contrary, Kaplan-Meier analysis showed that gain of cytoplasmic p27 was associated with a poor 5-year survival of metastatic melanoma patients (P < 0.001). Multivariate Cox regression analysis revealed that positive cytoplasmic p27 expression is an independent prognostic factor to predict metastatic melanoma patient outcome.
CONCLUSION: Cytoplasmic p27 may serve as a promising prognostic marker for metastatic melanoma.
IMPACT: Because there is no reliable prognostic marker for metastatic melanoma, our finding may have important clinical implications using cytoplasmic p27 as a prognostic biomarker for advanced melanoma.

PMID: 21828232 [PubMed - indexed for MEDLINE]

The determinants of periorbital skin ageing in participants of a melanoma case-control study in the U.K.

Br J Dermatol. 2011 Nov;165(5):1011-21

Authors: Suppa M, Elliott F, Mikeljevic JS, Mukasa Y, Chan M, Leake S, Karpavicius B, Haynes S, Bakker E, Peris K, Barrett JH, Bishop DT, Newton Bishop JA

Abstract
BACKGROUND: Skin ageing is said to be caused by multiple factors. The relationship with sun exposure is of particular interest because the detrimental cutaneous effects of the sun may be a strong motivator to sun protection. We report a study of skin ageing in participants of an epidemiological study of melanoma.
OBJECTIVES: To determine the predictors of periorbital cutaneous ageing and whether it could be used as an objective marker of sun exposure.
METHODS: Photographs of the periorbital skin in 1341 participants were graded for wrinkles, degree of vascularity and blotchy pigmentation and the resultant data assessed in relation to reported sun exposure, sunscreen use, body mass index (BMI), smoking and the melanocortin 1 receptor (MC1R) gene status. Data were analysed using proportional odds regression.
RESULTS: Wrinkling was associated with age and heavy smoking. Use of higher sun-protection factor sunscreen was protective (P = 0·01). Age, male sex, MC1R variants ('r', P=0·01; 'R', P=0·02), higher reported daily sun exposure (P=0·02), increased BMI (P=0·01) and smoking (P=0·02) were risk factors for hypervascularity. Blotchy pigmentation was associated with age, male sex, higher education and higher weekday sun exposure (P=0·03). More frequent sunscreen use (P=0·02) and MC1R variants ('r', P=0·03; 'R', P=0·001) were protective.
CONCLUSIONS: Periorbital wrinkling is a poor biomarker of reported sun exposure. Vascularity is a better biomarker as is blotchy pigmentation, the latter in darker-skinned individuals. In summary, male sex, sun exposure, smoking, obesity and MC1R variants were associated with measures of cutaneous ageing. Sunscreen use showed some evidence of being protective.

PMID: 21787368 [PubMed - indexed for MEDLINE]

Multiplex serum biomarker assessments: technical and biostatistical issues.

J Transl Med. 2011;9:173

Authors: Butterfield LH, Potter DM, Kirkwood JM

Abstract
BACKGROUND: Identification of predictive and prognostic biomarkers for patients with disease and undergoing different therapeutic options is a very active area of investigation. Many of these studies seek biomarkers among circulating proteins accessed in blood. Many levels of standardization in materials and procedures have been identified which can impact the resulting data.
METHODS: Here, we have observed unexpected variability in levels of commonly tested analytes in serum which were processed and stored under standardized conditions. We have identified apparent changes in cytokine, chemokine and growth factor levels detected by multiplex Luminex assay in melanoma patient and healthy donor serum samples, over storage time at -80°C. Controls included Luminex kit standards, multiplexed cytokine standards and WHO cytokine controls. Data were analyzed by Wilcoxon rank-sum testing and Spearman's test for correlations.
RESULTS: The interpretation of these changes is confounded by lot-to-lot kit standard curve reagent changes made by a single manufacturer of Luminex kits.
CONCLUSIONS: This study identifies previously unknown sources of variation in a commonly used biomarker assay, and suggests additional levels of controls needed for identification of true changes in circulating protein levels.

PMID: 21989127 [PubMed - indexed for MEDLINE]