Molecular characterization of fast-growing melanomas

BACKGROUND

The rate of growth of primary melanoma is a robust predictor of aggressiveness, but the mutational profile of fast-growing melanomas (FGMM) and the potential to stratify patients at high risk of death has not been comprehensively studied.

OBJECTIVE

To investigate the epidemiologic, clinical, and mutational profile of primary cutaneous melanomas with a thickness ≥ 1 mm, stratified by rate of growth.

METHODS

Observational prospective study. Deep-targeted sequencing of 40 melanoma driver genes on formalin fixed, paraffin-embedded primary melanoma samples. Comparison of FGMM (rate of growth > 0.5 mm/month) and nonFGMM (rate of growth ≤ 0.5 mm/month).

RESULTS

Two hundred patients were enrolled, among wom 70 had FGMM. The relapse-free survival was lower in the FGMM group (P = .014). FGMM had a higher number of predicted deleterious mutations within the 40 genes than nonFGMM (P = .033). Ulceration (P = .032), thickness (P = .006), lower sun exposure (P = .049), and fibroblast growth factor receptor 2 (FGFR2) mutations (P = .037) were significantly associated with fast growth.

LIMITATIONS

Single-center study, cohort size, potential memory bias, number of investigated genes.

CONCLUSION

Fast growth is linked to specific tumor biology and environmental factors. Ulceration, thickness, and FGFR2 mutations are associated with fast growth. Screening for FGFR2 mutations might provide an additional tool to better identify FGMM, which are probably good candidates for adjuvant therapies.

PTEN, ATM, IDH1 mutations and MAPK pathway activation as modulators of PFS and OS in patients treated by first line EGFR TKI, an ancillary study of the French Cooperative Thoracic Intergroup (IFCT) Biomarkers France project

OBJECTIVES

Tumor mutation screening is standard of care for patients with stage IV NSCLC. Since a couple of years, widespread NGS approaches used in routine diagnostics to detect driver mutations such as EGFR, KRAS, BRAF or MET allows the identification of other alterations that could modulated the intensity or duration of response to targeted therapies. The prevalence of co-occurring alterations that could affect response or prognosis as not been largely analyzed in clinical settings and large cohorts of patients. Thanks to the IFCT program "Biomarkers France", a collection of samples and data at a nation-wide level was available to test the impact of co-mutations on first line EGFR TKI in patients with EGFR mutated cancers.

MATERIALS AND METHODS

Targeted NGS was assessed on available (n = 208) samples using the Ion AmpliSeq™ Cancer Hotspot Panel v2 to screen for mutations in 50 different cancer genes.

RESULTS

This study showed that PTEN inactivating mutations, ATM alterations, IDH1 mutations and complex EGFR mutations were predictors of short PFS in patients with a stage 4 lung adenocarcinoma receiving first line EGFR TKI and that PTEN, ATM, IDH1 and KRAS mutations as well as alterations in the MAPK pathway were related to shorter OS.

CONCLUSION

These findings may lead to new treatment options in patients with unfavorable genotypes to optimize first line responses.

Efficacy of Immune Checkpoint Inhibitors in KRAS-Mutant Non-Small Cell Lung Cancer (NSCLC)

INTRODUCTION

KRAS mutation is the most frequent molecular alteration found in advanced NSCLC; it is associated with a poor prognosis without available targeted therapy. Treatment options for NSCLC have been recently enriched by the development of immune checkpoint inhibitors (ICIs), and data about its efficacy in patients with KRAS-mutant NSCLC are discordant. This study assessed the routine efficacy of ICIs in advanced KRAS-mutant NSCLC.

METHODS

In this retrospective study, clinical data were extracted from the medical records of patients with advanced NSCLC treated with ICIs and with available molecular analysis between April 2013 and June 2017. Analysis of programmed death ligand 1 (PD-L1) expression was performed if exploitable tumor material was available.

RESULTS

A total of 282 patients with ICI-treated (in the first line or more) advanced NSCLC (all histological subgroups) who were treated with ICIs (anti-programmed death 1, anti-PD-L1, or anti-cytotoxic T-lymphocyte associated protein 4 antibodies), including 162 (57.4%) with KRAS mutation, 27 (9.6%) with other mutations, and 93 (33%) with a wild-type phenotype, were identified. PD-L1 analysis was available for 128 patients (45.4%), of whom 45.3% and 19.5% had PD-L1 expression of 1% or more and 50%, respectively (49.5% and 21.2%, respectively, in the case of the 85 patients with KRAS-mutant NSCLC). No significant difference was seen in terms of objective response rates, progression-free survival, or overall survival between KRAS-mutant NSCLC and other NSCLC. No significant differences in overall survival or progression-free survival were observed between the major KRAS mutation subtypes (G12A, G12C, G12D, G12V, and G13C). In KRAS-mutant NSCLC, unlike in non-KRAS-mutant NSCLC, the efficacy of ICIs is consistently higher, even though not statistically significant, for patients with PD-L1 expression in 1% or more of tumor cells than for those with PD-L1 expression in less than 1% of tumor cells, and this finding is especially true when PD-L1 expression is high (PD-L1 expression ≥50%).

CONCLUSION

For patients with KRAS-mutant NSCLC (all mutational subtypes), the efficacy of ICI is similar to that for patients with other types of NSCLC. PD-L1 expression seems to be more relevant for predicting the efficacy of ICIs in KRAS-mutant NSCLC than it is in other types of NSCLC.

Using Digital Droplet Polymerase Chain Reaction to Detect the Mosaic GNAS Mutations in Whole Blood DNA or Circulating Cell-Free DNA in Fibrous Dysplasia and McCune-Albright Syndrome

The GNAS postzygotic mosaic activating mutations involved in fibrous dysplasia and McCune-Albright syndrome (MAS) are not detectable in leukocytes by Sanger sequencing. Digital droplet polymerase chain reaction detects GNAS mutations in 7 of 12 patients (58.3%) suspected to have fibrous dysplasia/MAS from whole blood DNA, and in 4 of 5 patients (80%) from circulating cell-free DNA.

Proof of concept: prognostic value of the plasmatic concentration of circulating cell free DNA in desmoid tumors using ddPCR

Since desmoid tumors (DT) exhibit an unpredictable clinical course, with stabilization and/or spontaneous regression, an initial "wait-and-see" policy is the new standard of care-thus, the actual challenge is to identify early factors of progression. We present a method of detection of CTNNB1 mutations using a targeted digital droplet PCR (ddPCR) on cell-free DNA (cfDNA) extracted from blood samples of 31 DT patients. Furthermore, we analyzed the correlation between DT evolution and plasmatic concentration of total and mutated cfDNA at the time of diagnosis. Circulating copies of CTNNB1 mutants (ctDNA) were detected in the plasma of 6 patients (33%) but their concentration was not correlated with evolution of the tumor. Concentration of total cfDNA was higher in the plasma of patients with progressive desmoids (p = 0,0009). Using a threshold <900 copies/mL of plasma to detect indolent desmoid and a threshold >1375, it was possible to predict desmoid evolution for 65% of patients by measuring the quantity of circulating DNA in their plasma as early as the time of diagnosis. Albeit showing that the detection of CTNNB1 mutants is possible in the plasma of patients harboring a desmoid tumor, the results of this preliminary study raise the hypothesis that most of the circulating DNA detected in their plasma is derived from non-neoplastic cells, most likely normal neighboring tissues being actively invaded. Our results open the perspective of using cfDNA as a biomarker to predict prognosis at the time of diagnosis and assess tumor dynamics to optimize the treatment strategy.

Circulating cell free tumor DNA detection as novel biomarkers to monitor desmoid tumors evolution

11063

Background: Since desmoid tumors (DT) exhibit an unpredictable clinical course, with stabilization and/or spontaneous regression, an initial “wait-and-see” policy is the new standard of care to select best indications of active treatments in case of significant evolution. Therefore, translational research is crucial to identify predictive factors of progression. Most DT are characterized by CTNNB1 mutation (CM) in exon 3 (T41A, S45F, S45P). Circulating cell-free tumoral DNA (ctDNA), named "liquid biopsy", has emerged as a new promising non-invasive tool to detect biomarker in several cancers. Methods: We present a method of detection of DT-specific CM using a targeted strategy digital droplet PCR (ddPCR) on cell-free DNA (cfDNA) extracted from blood samples of 31 DT patients (pts). T41A, S45P, S45F and their respective CTNNB1 wild-type probe were designed for ddPCR. Furthermore, we analyzed the correlation of cfDNA levels (CTNNB1 wt/ml plasma) and evolution of the tumor. Results: Initial DT CM statuswas known for 28 pts and unknown for 3 pts. 24 pts presented a CM (17 pts T41A, 6 pts S45F and 1 pt S45P), 2 pts a mutation of APC, 2 pts were wild-type, and 3 pts were undetermined. Among pts with a CM, CTNNB1 mutants were detected in the cfDNA of 6 patients (19.4%). CM detection was not correlated with the quantity of cfDNA analyzed (p = 0,7263–Mann-Whitney (MW)). Absolute quantification of cfDNA (CTNNB1 wt) normalized by mL of plasma displayed higher levels for patients with progressive DT (p = 0,0009 - MW), this difference of cfDNA quantity was also present between progressive, stable and self-regressive DT (p = 0,0012 - MW). A threshold of 875 CTNNB1 copies/mL predicted DT progression with a sensibility of 100% (CI95%: 59-100) and a specificity of 76.5% (CI95%: 50.1-93.2). Absolute cfDNA quantity was also higher in patients harboring multiple desmoids (p = 0.0292 - MW). Conclusions: The absolute quantification of normalized cfDNA is correlated with evolution of the disease, independently of the initial tumor type of CM. This study opens the perspective of using cfDNA as a genomic biomarker to assess the tumor dynamics at initial diagnosis, and to monitor treatment strategy in case of tumor evolution.

[Immunohistochemical hormonal mismatch and human epidermal growth factor type 2 [HER2] phenotype of brain metastases in breast cancer carcinoma compared to primary tumors]

INTRODUCTION

Phenotype changes between primary tumor and the corresponding brain metastases are recent reported data. Breast cancer, with biological markers predicting prognosis and guiding therapeutic strategy remains an interesting model to observe and evaluate theses changes. The objective of our study was to compare molecular features (estrogen receptor [ER], progesterone receptor [PR], and human epidermal growth factor receptor type 2, [HER2]) between brain metastases and its primary tumor in patients presenting with pathologically confirmed breast cancer.

MATERIAL AND METHODS

This retrospective study was based on the immunohistochemical analysis of the brain metastases paraffin embedded samples stored in our institutional tumor bank, after surgical resection. The level of expression of hormonal receptors and HER2 on brain metastases were centrally reviewed and compared to the expression status in primary breast cancer from medical records.

RESULTS

Forty-four samples of brain metastases were available for analysis. Hormonal receptor modification status was observed in 11/44 brain metastases (25%) for ER and 6/44 (13.6%) for PR. A modification of HER2 overexpression was observed in brain metastases in 6/44 (13.6%). Molecular subtype modification was shown in 17 cases (38.6%). A significant difference was demonstrated between time to develop brain metastases in cases without status modification (HER2, ER and PR) (med=49.5months [7.8-236.4]) and in cases in which brain metastases status differs from primary tumor (med=27.5months [0-197.3]), (P=0.0244, IC95=3.09-51.62, Mann and Whitney test).

CONCLUSION

the main interest of this study was to focus on the molecular feature changes between primary tumor and their brain metastases. Time to develop brain metastases was correlated to phenotypic changes in brain metastases.

[Oncogenic drivers in daily practice improve overall survival in patients with lung adenocarcinoma]

BACKGROUND

EGFR tyrosine kinase inhibitors and crizotinib are nowadays the optimal treatment for metastatic lung cancer with activation of EGFR mutations and ALK rearrangement. In addition, several targeted agents are in development for lung cancer with other oncodrivers. In France, since 2011, six oncodrivers are routinely tested in patients with stage IV. The aim of this study was to assess whether systematic detection of oncodrivers and matched targeted therapy improve overall survival in patients with advanced lung adenocarcinoma.

METHODS

This study included all consecutive patients treated in our department for advanced lung adenocarcinoma from January 2012 to December 2013. We studied the impact in survival according to the presence of the driver and the targeted therapy.

RESULTS

Among the 261 patients included, oncodrivers alterations were found in 43.5% of patients: EML4-ALK fusion genes (2.1%), EGFR (10.3%), KRAS (27.7%), BRAF (2.5%), HER2 (0.8%), and PI3KCA (0.8%) mutations. Twenty-nine percent of patients (n=32) with oncodrivers received matched targeted therapy. Patient treated by targeted agent appropriate to an oncogenic driver had a median survival of 21.1 months (95% CI: 14.7-27.5). The patients (n=79) who did not receive targeted therapy had a median survival of 6.6 months (95% CI: 4.3-8.9). The patients (n=150) without identified driver had a median survival of 9.7 months (95% CI: 6.7-11.7); P<0.001.

CONCLUSION

An actionable oncodriver was routinely detected in nearly half of patients with advanced lung adenocarcinoma. This systematic detection may influence treatment outcomes, notably with matched targeted therapy.

Outcome of Epstein-Barr virus-associated primary breast cancer

The presence of the Epstein-Barr-virus (EBV) has been reported to be a pathogenic factor in breast cancer (BC). We previously demonstrated the aggressiveness of EBV-positive BC. The purpose of the present study was to evaluate the effect of EBV on the prognosis of BC according to the BC phenotype. A total of 117 patients with primary BC previously tested for the presence of EBV were evaluated. The presence of the virus was evaluated in breast specimens using quantitative PCR (qPCR). Disease-free survival (DFS) and overall survival (OS) were evaluated for 4 molecular subtypes, namely luminal A and B (lumA and lumB, respectively), human epidermal growth factor receptor 2 (HER2) and triple-negative (TN) subtypes and according to the EBV status. EBV positivity was observed in 32.5% of the cases. TN, HER2 and lumB tumours were more frequent among EBV-BC cases (P=0.02). The DFS rates were different between BC subtypes (P=0.002), but the differences were not statistically significant when the cases were stratified according to the EBV status (P=0.08 for EBV-negative and 0.06 for EBV-positive cases). The OS rates were similar for BC subtypes (P= 0.50) and when the cases were stratified according to the EBV status (P=0.16 and P=0.67 for EBV-positive and -negative cases, respectively). EBV was not associated with DFS or OS, in contrast to BC phenotypes, tumour size or nodal status. Therefore, EBV positivity was found to exert no effect on survival, despite its association with aggressive BC phenotypes.

Rapid deaminator status is associated with poor clinical outcome in pancreatic cancer patients treated with a gemcitabine-based regimen

BACKGROUND

Gemcitabine is a mainstay in the treatment of biliary and pancreatic cancers, with limited efficacy in most settings. The gemcitabine elimination pattern is primarily driven by deamination in the liver by CDA. CDA is affected by genetic polymorphisms, leading to marked variations in activity and, subsequently, to erratic drug plasma exposures in patients administered with standard dosage. CDA deficiency has been a rising concern with gemcitabine since several studies have proven that poor metabolizer patients experience life-threatening toxicities upon drug intake. In theory, ultrarapid metabolizer (UM) patients should be conversely at risk of treatment failure, although thus far few studies have addressed this issue in digestive oncology.

PATIENTS & METHODS

A pilot study was conducted on 40 pancreatic cancer patients, all treated with gemcitabine-based therapy. CDA status was primarily established on a phenotypic basis determined by measurement of residual CDA enzymatic activity in serum. Additionally, a search for c208G>A and c79A>C polymorphisms was carried out.

RESULTS

No patients carrying c208G>A polymorphisms were found, and only heterozygous c79A>C patients were observed. Eight out of the 40 patients (i.e., 20%) were identified as UM, with CDA activities over 6 U/mg. CDA activity was significantly different between progressive disease patients and patients with controlled disease (8.4 vs 3 U/mg; p < 0.001). Conversely, fewer gemcitabine-related severe toxicities were observed in UM patients.

CONCLUSION

This pilot study strongly suggests that UM patients are nearly five-times more likely to have progressive disease than patients with normal or low CDA activities, and that beside molecular events at the tumor level, upstream deregulations affecting drug disposition should be taken into account.

Noninvasive near-infrared fluorescent protein-based imaging of tumor progression and metastases in deep organs and intraosseous tissues

Whole-body imaging of experimental tumor growth is more feasible within the near-infrared (NIR) optical window because of the highest transparency of mammalian tissues within this wavelength spectrum, mainly due to improved tissue penetration and lower autofluorescence. We took advantage from the recently cloned infrared fluorescent protein (iRFP) together with a human immunodeficiency virus (HIV)-based lentiviral vector to produce virally transduced tumor cells that permanently express this protein. We then noninvasively explored metastatic spread as well as primary tumor growth in deep organs and behind bone barriers. Intrabone tumor growth was investigated through intracranial and intratibial injections of glioblastoma and osteosarcoma cells, respectively, and metastasis was assessed by tail vein injection of melanoma cells. We found that the emitted fluorescence is captured as sharp images regardless of the organ or tissue considered. Furthermore, by overlaying fluorescence spots with the white light, it was possible to afford whole-body images yet never observed before. This approach allowed us to continuously monitor the growth and dissemination of tumor cells with a small number of animals, minimal animal handling, and without the need for any additive. This iRFP-based system provides high-resolution readouts of tumorigenesis that should greatly facilitate preclinical trials with anticancer therapeutic molecules.

Association of matrix metalloproteinase 2 plasma level with response and survival in patients treated with bevacizumab for recurrent high-grade glioma

BACKGROUND

A predictive marker of bevacizumab activity is an unmet medical need. We evaluated the predictive value of selected circulating prebiomarkers involved in neoangiogenesis and invasion on patient outcome in recurrent high-grade glioma treated with bevacizumab.

METHODS

Analyzed in plasma were a set of 11 prebiomakers of interest (vascular endothelial growth factor receptor [VEGF]; VEGF receptor 2; basic fibroblast growth factor; stromal cell derived factor 1; placenta growth factor; urokinase-type plasminogen activator; plasminogen activator inhibitor 1; matrix metalloproteinases 2, 7, and 9; and adrenomedulline), using ELISA, at baseline and 2 weeks after bevacizumab initiation in a prospective cohort of 26 patients (Cohort 1). Correlations were validated in a separate retrospective cohort (Cohort 2; n = 50) and tested in cohort patients treated with cytotoxic agents without bevacizumab (Cohort 3; n = 34). Dosages were correlated to objective response, progression-free survival (PFS), and overall survival (OS).

RESULTS

In Cohort 1, high MMP2 baseline level was associated with a probability of objective response of 83.3% versus 15.4% for low MMP2 level (P = .001). In multivariate analysis, baseline level of MMP2 correlated with PFS (hazard ratio, 3.92; 95% confidence interval [CI]:1.46-10.52; P = .007) and OS (hazard ratio, 4.62; 95% CI: 1.58-13.53; P = .005), as decrease of VEGF (P = .038 for PFS and P = .013 for OS) and MMP9 (P = .016 for PFS and P = .025 for OS). In Cohort 2, MMP2, but not MMP9, confirmed its predictive significance. In Cohort 3, no association was found between MMP2, MMP9, and outcome.

CONCLUSION

In patients with recurrent high-grade glioma treated with bevacizumab, but not with cytotoxic agent, high MMP2 plasma levels are associated with prolonged tumor control and survival. MMP2 should be tested in randomized clinical trials that evaluate bevacizumab efficacy, and its biological role reassessed.

Adrenomedullin blockade suppresses growth of human hormone-independent prostate tumor xenograft in mice

PURPOSE

To study the role of the adrenomedullin system [adrenomedullin and its receptors (AMR), CLR, RAMP2, and RAMP3] in prostate cancer androgen-independent growth.

EXPERIMENTAL DESIGN

Androgen-dependent and -independent prostate cancer models were used to investigate the role and mechanisms of adrenomedullin in prostate cancer hormone-independent growth and tumor-associated angiogenesis and lymphangiogenesis.

RESULTS

Adrenomedullin and AMR were immunohistochemically localized in the carcinomatous epithelial compartment of prostate cancer specimens of high grade (Gleason score >7), suggesting a role of the adrenomedullin system in prostate cancer growth. We used the androgen-independent Du145 cells, for which we demonstrate that adrenomedullin stimulated cell proliferation in vitro through the cAMP/CRAF/MEK/ERK pathway. The proliferation of Du145 and PC3 cells is decreased by anti-adrenomedullin antibody (αAM), supporting the fact that adrenomedullin may function as a potent autocrine/paracrine growth factor for prostate cancer androgen-independent cells. In vivo, αAM therapy inhibits the growth of Du145 androgen-independent xenografts and interestingly of LNCaP androgen-dependent xenografts only in castrated animals, suggesting strongly that adrenomedullin might play an important role in tumor regrowth following androgen ablation. Histologic examination of αAM-treated tumors showed evidence of disruption of tumor vascularity, with depletion of vascular as well as lymphatic endothelial cells and pericytes, and increased lymphatic endothelial cell apoptosis. Importantly, αAM potently blocks tumor-associated lymphangiogenesis, but does not affect established vasculature and lymphatic vessels in normal adult mice.

CONCLUSIONS

We conclude that expression of adrenomedullin upon androgen ablation in prostate cancer plays an important role in hormone-independent tumor growth and in neovascularization by supplying/amplifying signals essential for pathologic neoangiogenesis and lymphangiogenesis. Clin Cancer Res; 19(22); 6138-50. ©2013 AACR.

Association of matrix metalloproteinase 2 (MMP2) baseline plasma level to objective response (OR), progression free survival (PFS), and overall survival (OS) and changes under treatment in patients treated with bevacizumab (Bev) for recurrent high-grade glioma (HGG)

2024

Background: Predictive marker of Bev activity is an unmet medical need. We evaluated predictive value of selected circulating prebiomarkers involved in neoangiogenesis and invasion on patient outcome in recurrent HGG treated with Bev. Methods: A set of eleven prebiomakers of interest (VEGF, VEGF-R2, bFGF, SDF1, PlGF, uPA, PAI1, MMP2, MMP7, MMP9, and adrenomedulline) were analyzed in plasma, using ELISA, at baseline from Bev initiation in a prospective cohort of 26 patients (Cohort1). Correlations were validated in a separate retrospective Bev treated cohort (Cohort2; n = 50) and then tested in a cohort of patients treated with cytotoxic agents without Bev (Cohort3; n = 34). Dosages were correlated to OR, PFS, and OS. MMP2 and MMP9 were then analyzed at multiple time points up to progression. Results: In cohort1, high MMP2 baseline level was associated with an OR rate of 83.3% for high levels versus 15.4% for low MMP2 levels (p = 0.001). In multivariate analysis, MMP2 baseline level was correlated with PFS (hazard-ratio (HR), 3.92; 95% confidence-interval (CI):1.46-10.52; p = 0.007) and OS (HR, 4.62; 95%CI 1.58-13.53; p = 0.005), as MMP9 (p = 0.016 for PFS and p = 0.025 for OS). Similar results were found in cohort2 for MMP2, (MMP2: p<0.001 for OR; p = 0.009 for PFS; p = 0.009 for OS) but not for MMP9. In cohort3, no association was found between MMP2, MMP9 and outcome. Significant changes in MMP2 and MMP9 plasma levels were observed during treatment. MMP2 increased after Bev initiation (p = 0.002), and decreased at progression (p = 0.002) while MMP9 initially decreased (p = 0.007) then increased at progression (p = 0.031). Conclusions: In patients with recurrent HGG treated with bevacizumab, but not with cytotoxic agents, high MMP2 plasma levels are associated with prolonged tumor control and survival while changes over time may reflect tumor control. MMP2 should be tested in randomized clinical trials that evaluate bevacizumab efficacy, and its biological role should be reassessed.

Cytidine deaminase status as a predictive marker in patients with hematologic malignancies treated with azacytidine or cytarabine

7117

Background: Cytarabine and azacytidine are mainstays for treating haematological malignancies. As most nucleosidic analogs, both azacytidine and cytarabine are metabolized in the liver by an exclusive enzymatic step driven by cytidine deaminase (CDA). CDA is highly polymorphic and dysregulations have been repeatedly associated with poor clinical outcome with gemcitabine. Methods: We have used a test to determine, on a phenotype basis, CDA status in patients. This test was used prospectively in a subset of 39 adult patients (16F, 23M, mean age 77 years), all treated for various haematological malignancies (i.e., CML, AML, lymphomas, myelodysplastic syndromes) with either aza-cytidine or a cytarabine-containing regimen. Response and treatment-related toxicities were monitored following current standards. In addition, impact of CDA status on azacytidine tolerance was evaluated in mice with or without CDA deficiency, as a proof of concept for the actual implication of metabolic deregulations in the toxicities observed in patients. Results: In patients, mean CDA activity was 3.7 +/-2.8 U/mg (min: 1, max: 14.8 U/mg). Ten out of 39 patients (i.e., 25%) showed low CDA activities and were considered as PM. Conversely, 8 patients (i.e., 20%) displayed CDA activities particurlary elevated (i.e., > 6U/mg) and were considered as UM patients. Of note, PM patients all showed severe toxicities, including two toxic-deaths. Conversely, UM patients showed little efficacy when treated with either azacytidine or cytarabine. In mice with CDA-deficiency, standard azacytidine led to profound and long-lasting neutropenia, as compared with normal mice. Drug monitoring confirmed that individuals with low CDA activity and toxicities showed higher concentrations of azacytidine as compared with normal individuals. Conclusions: Overall this pilot study strongly suggests that CDA status could be a relevant marker for predicting clinical outcome in patients treated with either azacytidine or cytarabine. CDA status could be further used as a covariate to tailor drug dosage so as to ensure an optimal efficacy/toxicity balance in patients with haematological malignancies.

Biomarkers (BM) France: Results of routine EGFR, HER2, KRAS, BRAF, PI3KCA mutations detection and EML4-ALK gene fusion assessment on the first 10,000 non-small cell lung cancer (NSCLC) patients (pts)

8000

Background: Personalized medicine is now a reality for advanced NSCLC pts on the basis of routine screening for EGFR mutation and ALK gene fusion assessment. The French NCI (INCa) also decided to additionally fund the routine assessment of 4 additional BM (HER2, KRAS, BRAF, PI3KCA). Methods: Starting on April 2012, these BM analyses were prospectively collected into a database head by the IFCT (www.ifct.fr) with 15-20,000 analyses awaited after one year. The physicians prescribing each of these BM analyses were then connected to this database and were asked to regularly complete epidemiological, clinical and therapeutic data for each corresponding patient. Results: 10,000 BM analyses were collected and entered into the BM France database at the time of this first analysis (January 2013). On the basis of available data, the patients were mainly male (63.8%), (ex)smokers (83.3%) and stage IV pts (64%). The tumors were mainly adenocarcinomas (76.1%). The samples for BM analysis were collected under bronchoscopy, surgery or transthoracic biopsy in 27.4, 28.1 and 24.2%, respectively. The 10,000 molecular profiles were characterized by 9.4% EGFR (including 0.8% EGFR resistant), 0.9% HER2, 26.9% KRAS, 1.6% BRAF, and 2.6% PI3KCA mutated and 4.0% EML4-ALK fusion genes. Double mutations were seen in 0.9% of the tumors. On January 2013, data on treatment were available for 18.6% of patients among whom 56.9% of patients received a treatment according to their molecular profile (labeled drugs or bio-guided trials). Updated data will be presented during the meeting. Conclusions: Biomarkers France is the largest ever conducted biomolecular study on advanced NSCLC patients and provides solid data on the value of a nationwide BM screening policy for NSCLC patients.

Expression of adrenomedullin in human colorectal tumors and its role in cell growth and invasion in vitro and in xenograft growth in vivo

Adrenomedullin (AM) is a multifunctional peptide vasodilator that transduces its effects through calcitonin receptor-like receptor/receptor activity-modifying protein-2 and -3 (CLR/RAMP2 and CLR/RAMP3). In this study, real-time quantitative reverse transcription demonstrated a significant expression of AM mRNA in tumor samples from colorectal cancer (CRC) patients in clinical stage II, III, and IV when compared with normal colorectal tissue. AM, CLR, RAMP2, and RAMP3 proteins were immunohistochemically localized in the carcinomatous epithelial compartment of CRC tissue. Tissue microarray analysis revealed a clear increase of AM, CLR, RAMP2, and RAMP3 staining in lymph node and distant metastasis when compared with primary tumors. The human colon carcinoma cells HT-29 expressed and secreted AM into the culture medium with a significant increase under hypoxia. Treatment of HT-29 cells with synthetic AM stimulated cell proliferation and invasion in vitro. Incubation with anti-AM antibody (αAM), anti-AM receptors antibodies (αAMR), or AM antagonist AM_22–52 inhibited significantly basal levels of proliferation of HT-29 cells, suggesting that AM may function as an autocrine growth factor for CRC cells. Treatment with αAM significantly suppressed the growth of HT-29 tumor xenografts in vivo. Histological examination of αAM-treated tumors showed evidence of disruption of tumor vascularity with decreased microvessel density, depletion of endothelial cells and pericytes, and increased tumor cell apoptosis. These findings highlight the potential importance of AM and its receptors in the progression of CRC and support the conclusion that αAM treatment inhibits tumor growth by suppression of angiogenesis and tumor growth, suggesting that AM may be a useful therapeutic target.

Tubulin isoforms identified in the brain by MALDI in-source decay

Identification of biomarkers is a major issue for enhancement of chemotherapies. The molecular characterization of tissues necessitates the identification of thousands of biomolecules each participating in physiopathological processes. MALDI in-source decay (ISD) fragmentation has already been proven to be effective for protein characterization. However, the difficulty to identify proteins from complex mixtures such as tissue sections can limit the applications of this technique. In this study, we evidenced that tubulin has an unusual fragmentation pathway in the MALDI source. This striking property allowed the detecting of several mouse brain tubulin isotypes simultaneously by simply using laser fragmentation. Tubulin isoforms are consistent markers of a bad prognosis of solid tumors and could be the target of targeted chemotherapies. Such a direct molecular printout of tubulin in tissues is a milestone that should be useful either at preclinical or clinical stage.

BRAF mutation as a pejorative marker in metastatic melanoma

8555

Background: BRAF mutation in melanoma has been shown to be associated with a trend in favour of a spontaneous worse outcome after metastases in a series of 197 patients in Australia. Objective: To correlate BRAF status in metastatic melanoma with clinicopathologic features and outcome. Methods: In our department in France 182 patients with metastatic melanoma have been tested for BRAF mutation between September 2009 and September 2011. Survival was assessed by log-rank test. Multivariate analysis was performed with Cox model. Results: From 182 patients, 88 (48.3%) were B-RAF mutant; 77 (87.5%) V600E, 4 (4.5%) V600K, and 7 (8%) other mutation subtypes. BRAF-mutant patients were younger than BRAF wild-type patients at diagnosis of primary melanoma (median age 52.3 vs 60.7 years, respectively, p=0.003), and at diagnosis of distant metastasis (median age 53.6 vs 64.1 years respectively, p=0.002). 34 patients were treated by B-RAF inhibitors. There was no significant difference in other demographic features of patients with metastatic melanoma by mutation status. Features of the primary melanoma significantly associated with a BRAF mutation (p<0.05) were histopathologic subtype (SSM), high mitotic rate (≥1/mm2), lower Breslow thickness (median Breslow: 2.2 vs 3.5 mm for BRAF mutant and BRAF-wild-type patients respectively, p=0.016), truncal location and location on occasionally exposed at sun site.The interval from diagnosis of first ever melanoma to first distant metastasis was not significantly different in BRAF-mutant and wild-type patients. The median overall survival (OS) from diagnosis of primary melanoma was 6.5 years for BRAF wild-type patients. Median OS was not reached in BRAF-mutant patients treated (34 of 88) with a BRAF inhibitor, but also in those not treated (p=0.24, and p=0.06 for treated BRAF-mutant vs BRAF wild-type). The overall survival from diagnosis of first distant metastasis was not significantly different (p=0.75). These results remained unchanged in a multivariate analysis. Conclusions: Our results confirm the characteristics of BRAF-mutant metastatic patients, and the efficacy of B-RAF inhibitors, but not that the presence of mutant-BRAF is per se a pejorative predictive marker.

P4-09-29: A Nomogram To Predict Prognosis in Node-Negative Breast Carcinoma

Background: Currently, the usefulness of conventional markers for breast carcinoma is limited to assess individual outcome. A statistical model was developed to improve the prognostic accuracy using multiple conventional and emerging prognostic biomarkers.

Methods: A total of 305 node-negative breast carcinomas who underwent surgery (+/− radiotherapy) but no adjuvant treatment was selected. Putative prognosis factors including age, tumor size, ER, PR, SBR grading, urokinase plasminogen activator (uPA), plasminogen activator inhibitor type 1 (PAI-1) and thymidine kinase (TK) were evaluated. The developed model was internally validated using Harrell's concordance index and calibrated. An external validation of the new model is warranted.

Results: Age (p&lt;0.001), PR (p= 0.02), and PAI-1(p=&lt;0.001) were included in the Cox regression model predicting overall survival at 5-years. Internal validation revealed a concordance index of 0.711 to 0.694 before and after calibration.

Conclusion: A nomogram can be used to predict probability survival curves for individual breast cancer patients and the effect of treatment options can be evaluated using these models.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-09-29.

Cetuximab after bevacizumab in metastatic colorectal cancer: is it the best sequence?

BACKGROUND

Chemotherapy combinations and addition of cetuximab or bevacizumab to chemotherapy have been shown to improve overall survival of metastatic colorectal cancer (CRC) patients. However, the efficacy of cetuximab when administered after bevacizumab failure is still unknown.

METHODS

Fifty-eight consecutive patients diagnosed with advanced colorectal cancer between treated with cetuximab following irinotecan failure were included in our analysis. A multivariate Cox model analysis was performed to estimate the effect of previous bevacizumab regimen on survival.

RESULTS

Thirteen (22.4%) were pre-treated with anti-VEGF agents. None of them responded to cetuximab, and this subgroup presented a significantly decreased disease-specific survival as compared to treatment-naïve patients (9.1 months vs. 4.9 months; p=0.026). This difference remained statistically significant in a multivariate Cox model after adjusting for age, sex, performance status (PS), and K-RAS status (RR=2.2; 95% CI: 1.1-4.5, p=0.03).

CONCLUSION

These study results suggest that a previous anti-VEGF therapy decrease cetuximab efficiency.

IDH mutation status impact on in vivo hypoxia biomarkers expression: new insights from a clinical, nuclear imaging and immunohistochemical study in 33 glioma patients

Mutations in the gene encoding isocitrate dehydrogenase enzyme isoforms 1 (IDH1) and 2 (IDH2) have recently been identified in a large proportion of glial tumors of the CNS, but their mechanistic role in tumor development remains unclear. Here, we assessed the actual impact of IDH1 and IDH2 mutations in patients harboring WHO grade II and III gliomas. We sequenced IDH1 at codon 132 and IDH2 at codon 172 in 33 patients with WHO grade II and III gliomas who benefited from a preoperative (18)F-FDG positron emission tomography (PET). Immunohistochemical expression of Hypoxia Inducible Factor-1alpha (HIF-1α), Carbonic Anhydrase IX (CAIX), Glucose Transporter 1 (GLUT1) and Caspase 3 active form (CASP3) along with the R132HIDH1 mutation was assessed in all cases as well as 1p/19q deletion status and p53 expression. HIF-1α expression was found in 15% of IDH-mutated compared to 7.7% of IDH-nonmutated tumors (P = 0.954). Also, GLUT-1 positive staining was found in 5% of IDH-mutated and in 7.1% of IDH-nonmutated tumors (P = 0.794). Finally, CA-IX expression was found in 15% of IDH-mutated and in 7.7% of IDH-nonmutated tumors (P = 0.484). The combined expression of these three hypoxic markers was found in two WHO grade III tumors, one of which was IDH-mutated whereas the other was IDH-nonmutated (P = 0.794). In IDH-mutated tumors, the median SUVmax ratio was 2.24 versus 2.15 in IDH-nonmutated tumors (P = 0.775). Together, these data question the actual relationship between IDH mutation status and in vivo hypoxic biomarkers expression in WHO grade II and III gliomas.

Epstein-Barr virus as a marker of biological aggressiveness in breast cancer

Purpose:

Although a potential role of the Epstein-Barr virus (EBV) in the pathogenesis of breast cancer (BC) has been underlined, results remain conflicting. Particularly, the impact of EBV infection on biological markers of BC has received little investigation.

Methods:

In this study, we established the frequency of EBV-infected BC using real-time quantitative PCR (RT–PCR) in 196 BC specimens. Biological and pathological characteristics according to EBV status were evaluated.

Results:

EBV DNA was present in 65 of the 196 (33.2%) cases studied. EBV-positive BCs tended to be tumours with a more aggressive phenotype, more frequently oestrogen receptor negative (P=0.05) and with high histological grade (P=0.01). Overexpression of thymidine kinase activity was higher in EBV-infected BC (P=0.007). The presence of EBV was weakly associated with HER2 gene amplification (P=0.08).

Conclusion:

Our study provides evidence for EBV-associated BC undergoing distinct carcinogenic processes, with more aggressive features.