SUV calculation in breast cancer: which normalization should be applied when using 18F-FDG PET?

BACKGROUND: When using 18F-FDG PET, glucose metabolism quantification is affected by various factors. We aimed to investigate the benefit of different standardized uptake value (SUV) normalizations to improve the accuracy of 18F-FDG uptake to predict breast cancer aggressiveness and response to treatment. METHODS: Two hundred fifty-two women with locally advanced breast cancer treated with neoadjuvant chemotherapy (NAC) were included. Women underwent 18F-FDG PET before and after the first course of NAC. Glucose serum levels, patient heights and weights were recorded at the time of each PET exam. Four different procedures for SUV normalization of the primary tumor were used: by body weight (SUVBW) by blood glucose level (SUVG), by lean body mass (SUL) and then corrected for both lean body mass and blood glucose level (SULG). RESULTS: At baseline, SUL was significantly lower than SUVBW (5.9±4.0 and 9.5±6.5, respectively; P<0.0001), whereas SUVG and SUVBW were not significantly different (9.7±6.4 and 9.5±6.5, respectively; P=0.67). Concerning SUV changes (ΔSUV), the different normalizations methods did not induce significant quantitative differences. The correlation coefficients were high between the four normalizations methods of SUV1, SUV2 and ΔSUVB (R>0.95; P<0.0001). High baseline SUVBW measures were positively correlated with the biological tumor characteristics of aggressiveness and proliferation (P<0.001): ductal carcinoma, high tumor grading, high mitotic activity, negative estrogen receptor status and the TNBC subtype. ΔSUVBW was highly predictive of pCR (AUC=0.76 on ROC curve analysis; P<0.0001). The different SUV normalizations yields identical statistical results and AUC to predict tumor biological aggressiveness and response to therapy. CONCLUSIONS: In the present setting, SUVBW and SUL can be considered as robust measures and be used in future multicenter trials. The additional normalization of SUV by glycemia involves stringent methodologic procedures to avoid biased risk measurements and offers no statistical advantages.

Induction of oxiapoptophagy, a mixed mode of cell death associated with oxidative stress, apoptosis and autophagy, on 7-ketocholesterol-treated 158N murine oligodendrocytes: impairment by α-tocopherol.

7-Ketocholesterol (7KC) has been suggested to induce a complex mode of cell death on monocytic cells: oxiapoptophagy (OXIdation, APOPTOsis, and autoPHAGY) (Monier et al. (2003) [12]). The aim of the present study, realized on 158N murine oligodendrocytes, was to bring new evidence on this mixed form of cell death. On 158N cells, 7KC induces an overproduction of reactive oxygen species (ROS) revealed by dihydroethidium staining, a loss of transmembrane mitochondrial potential measured with DiOC6(3), caspase-3 activation, and condensation and/or fragmentation of the nuclei which are typical criteria of oxidative stress and apoptosis. Moreover, 7KC enhances cytoplamic membrane permeability to propidium iodide, and induces acidic vesicular organelle formation evaluated with acridine orange. In addition, 7KC promotes conversion of microtubule-associated protein light chain 3 (LC3-I) to LC3-II which is characteristic of autophagy. These different side effects were impaired by α-tocopherol. Altogether, our data demonstrate that oxiapoptophagy including ROS overproduction, apoptosis and autophagy could be a particular type of cell death activated by 7KC which can be inhibited by α-tocopherol.

¹8F-FDG PET/CT provides powerful prognostic stratification in the primary staging of large breast cancer when compared with conventional explorations.

PURPOSE: The objective of this study was to assess the impact on management and the prognostic value of (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT for initial staging of newly diagnosed large breast cancer (BC) when compared with conventional staging. METHODS: We prospectively included 142 patients with newly diagnosed BC and at least grade T2 tumour. All patients were evaluated with complete conventional imaging (CI) procedures (mammogram and/or breast ultrasound, bone scan, abdominal ultrasound and/or CT, X-rays and/or CT of the chest), followed by FDG PET/CT exploration, prior to treatment. The treatment plan based on CI staging was compared with that based on PET/CT findings. CI and PET/CT findings were confirmed by imaging and clinical follow-up and/or pathology when assessable. Progression-free survival (PFS) was analysed using the Cox proportional hazards regression model. RESULTS: According to CI staging, 79 patients (56%) were stage II, 46 (32%) stage III and 17 (12%) stage IV (distant metastases). Of the patients, 30 (21%) were upstaged by PET/CT, including 12 (8%) from stage II or III to stage IV. On the other hand, 23 patients (16%) were downstaged by PET/CT, including 4 (3%) from stage IV to stage II or III. PET/CT had a high or medium impact on management planning for 18 patients (13%). Median follow-up was 30 months (range 9-59 months); 37 patients (26%) experienced recurrence or progression of disease during follow-up and 17 patients (12%) died. The Cox model indicated that CI staging was significantly associated with PFS (p = 0.01), but PET/CT staging provided stronger prognostic stratification (p < 0.0001). Moreover, Cox regression multivariate analysis showed that only PET/CT staging remained associated with PFS (p < 0.0001). CONCLUSION: FDG PET/CT provides staging information that more accurately stratifies prognostic risk in newly diagnosed large BC when compared with conventional explorations alone.

HER2-positive breast cancer: ¹8F-FDG PET for early prediction of response to trastuzumab plus taxane-based neoadjuvant chemotherapy.

PURPOSE: To investigate the value of (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET/CT) to predict a pathological complete response (pCR) after neoadjuvant chemotherapy (NAC) in women with human epidermal growth factor receptor 2 (HER2)-positive breast cancer. MATERIAL AND METHODS: Fifty-seven consecutive women with HER2-positive breast cancer, treated with trastuzumab plus taxane-based NAC, were prospectively included. Maximum Standardized Uptake Value of the primary tumor and axillary nodes were measured at baseline (PET1.SUVmax) and after the first course of NAC (PET2.SUVmax). Tumor metabolic volumes were assessed to determine Total Lesion Glycolysis (TLG). The tumor metabolic response (ΔSUVmax and ΔTLG) was calculated. RESULTS: In univariate analysis, negative hormonal receptor status (p = 0.04), high tumor grade (p = 0.03), and low tumor PET2.SUVmax (p = 0.001) were predictive of pCR. Tumor ΔSUVmax correlated with pCR (p = 0.03), provided that tumors with low metabolic activity at baseline were excluded. ΔTLG did not correlate with pCR. In multivariate analysis, tumor PET2.SUVmax < 2.1 was the best independent predictive factor (Odds ratio =14.3; p = 0.004) with both negative and positive predictive values of 76 %. Although the metabolic features of the primary tumor did not depend on hormonal receptor status, both the baseline metabolism and early response of axillary nodes were higher if estrogen receptors were not expressed (p = 0.01 and p = 0.03, respectively). CONCLUSION: In HER2-positive breast cancer, very low tumor residual metabolism after the first cycle of NAC (SUVmax < 2.1) was the main predictor of pCR. These results should be further explored in multicenter studies and incorporated into the design of clinical trials.

Dealing with dry waste disposal issues associated with 177mLu impurities: a long-term challenge for nuclear medicine departments.

PURPOSE: A strategy for management of radioactive waste associated with 177Lu-dotatate (Lutathera®) treatments was established in our institution, based on predicted storage times of 3-5 years extrapolated from the results of a 2-year measurement study. The aim of this work was to validate this strategy by identifying contaminants and confirming disposal based on the clearance level twice-the-background was within expected time frames. METHODS: We conducted a prospective series of measurements of radioactive waste associated with the first 65 treatments administered. Sequential measurements of the first 45 vials used were performed on a dose calibrator to identify contaminants. Exposure rates in contact were monitored with a dose ratemeter on a 6-monthly basis for all waste stored: 46 empty vials, 19 vials partially used and 61 biohazard containers. RESULTS: Initial median activity of the first vials used was 118 MBq [4-4188 MBq]. For each vial, the decay curve of activity obtained was adjusted to a bi-exponential model. The major component, representing 99.7% of the activity, has a median half-life of 6.6 days [5.7-7.2 days] corresponding to 177Lu. The second, representing only 0.3% of the activity and having a median half-life of 152 days [104-205 days] corresponding to 177mLu, determines necessary storage times. Partially used vials can be disposed of after 5 years, other waste after 3 years. Compliance with the regulatory clearance level is achieved within expected time frames. CONCLUSION: Although only present as traces, 177mLu associated with the direct production route results in major radioactive waste disposal issues for hospitals. Availability of radiopharmaceuticals without impurities appears to be crucial for an expanding use of targeted radionuclide therapy.

[Factors influencing platelets labelling with indium-111 oxine]. / Facteurs influençant le marquage des plaquettes à l'oxinate d'indium-111.

Autologous indium-111 labelled platelets can be used for kinetic studies in patients with autoimmune thrombocytopenic purpura [AITP]. The objective of this study was to evaluate some biological and clinical factors influencing the labeling efficiency. METHODS: We studied incubation media (Plasma media [MP] or dry media [MS]), platelet concentration [NP], mean platelet volume [VPM], hemoglobin level and pathology associated with AITP. RESULTS: This was a retrospective study of 93 platelets labelling (43 in MS and 50 in MP), 38 primary AITP (41%) and 55 secondary AITP (59%). The labeling efficiency was 72% (78% in MS versus 53% in MP; p < 0.0001). The labeling efficiency was correlated with VPM (p = 0.0004), NP (p = 0.03), hemoglobin level (p = 0.037) and type of AITP (p = 0.0036). The incubation medium, hemoglobin level and type of the AITP have an independent predictive value on the labeling efficiency. CONCLUSION: These data confirm the influence of the incubation medium on the labeling efficiency and identify two other predictive criteria, hemoglobin level and type of AITP.

[Effect of obesity, age and gender on glomerular filtration rate measured in normal adults]. / Influence de l'obésité, de l'âge et du sexe sur le débit de filtration glomérulaire mesuré chez l'adulte normal.

The aims of this study were to assess the dependence of glomerular filtration rate (GFR) on age and gender and to produce reference data for the interpretation of 51Cr-EDTA GFR measurements in adults. METHODS: This was a retrospective study of 120 live kidney donors (75 females, 45 males). GFR was evaluated from 51Cr-EDTA plasma clearance using blood samples taken at 3, 4 and 5 hours. The slope-intercept GFR was corrected for body surface area using the Dubois & Dubois and for the fast exponential using the Brochner-Mortensen equation. Scatter plot of DFG against age in live kidney donors was plotted and the 98% range limits have been defined. RESULTS: The median GFR obtained for kidney donors was 88 mL/min/1.73 m2 [68-130]. No significant difference with gender was found. 51Cr-EDTA clearance was strongly correlated with patient age (r = - 0.62, P < 0,0001). GFR decreased by approximately 8 mL/min/1.73 m2 per decade. Based on these results, a nomogram for GFR is presented. CONCLUSION: The interpretation of GFR requires age-adjusted normal values. These standards need not be adjusted to the patient's sex or BMI.

Comparison between tumour metabolism derived from 18F-FDG PET/CT and accurate cytogenetic stratification in newly diagnosed multiple myeloma patients.

BACKGROUND: 18F-fluorodeoxyglucose positron emission tomography integrated with computed tomography (18F-FDG PET/CT) is a useful tool for baseline staging in newly diagnosed multiple myeloma (MM) but also for prognostic stratification. This monocentric retrospective study aimed at examining the relation between baseline tumour metabolism assessed by 18F-FDG PET/CT and linear predictor (LP) score, a new cytogenetic stratification score. METHODS: From March 2012 to March 2019, 57 patients with newly diagnosed MM addressed to our institution for baseline 18F-FDG PET/CT were included. LP score was determined on systematic iliac crest bone marrow samples. Obtained on CD138-sorted bone marrow plasma cells, this recent composite cytogenetic stratification is a 6-marker based weighted score using fluorescence in situ hybridization (FISH) ± single nucleotide polymorphism (SNP) arrays. We compared quantitative metabolic parameters and LP score using a Kruskal-Wallis test and visual suspicion of diffuse bone marrow involvement (DBI; based on hepatic background as threshold of positivity) and cytogenetic data using a Chi-squared test. RESULTS: The distribution of total metabolic tumour volume (TMTV) and total lesion glycolysis (TLG) values among the three LP score categories was almost stochastic, with no significant association (P=0.70). Additionally, no significant association between TMTV/TLG and any of the six cytogenetic abnormalities included in LP score calculation. A significant association was found between visual high suspicion of DBI and LP score (P=0.036), and between this visual parameter and the presence of 1q gain (P=0.049). CONCLUSIONS: There is no significant association between quantitative metabolic parameters assessed with 18F-FDG PET/CT and LP score in patients with newly diagnosed MM, suggesting a potential complementarity of these biomarkers for prognostic stratification. A significant association was found between high visual suspicion of DBI and LP score.

Transarterial Radioembolization of Hepatocellular Carcinoma, Liver-Dominant Hepatic Colorectal Cancer Metastases, and Cholangiocarcinoma Using Yttrium90 Microspheres: Eight-Year Single-Center Real-Life Experience.

Liver tumors are common and may be unamenable to surgery or ablative treatments. Consequently, other treatments have been devised. To assess the safety and efficacy of transarterial radioembolization (TARE) with Yttrium-90 for hepatocellular carcinoma (HCC), liver-dominant hepatic colorectal cancer metastases (mCRC), and cholangiocarcinoma (CCA), performed according to current recommendations, we conducted a single-center retrospective study in 70 patients treated with TARE (HCC, n = 44; mCRC, n = 20; CCA, n = 6). Safety and toxicity were assessed using the National Cancer Institute Common Terminology Criteria. Treatment response was evaluated every 3 months on imaging studies using Response Evaluation Criteria in Solid Tumors (RECIST) or mRECIST criteria. Overall survival and progression-free survival were estimated using the Kaplan-Meier method. The median delivered dose was 1.6 GBq, with SIR-Spheres® or TheraSphere® microspheres. TARE-related grade 3 adverse events affected 17.1% of patients. Median follow-up was 32.1 months. Median progression-free survival was 5.6 months and median overall time from TARE to death was 16.1 months and was significantly shorter in men. Progression-free survival was significantly longer in women (HR, 0.49; 95%CI, 0.26-0.90; p = 0.031). Risk of death or progression increased with the number of systemic chemotherapy lines. TARE can be safe and effective in patients with intermediate- or advanced-stage HCC, CCA, or mCRC refractory or intolerant to appropriate treatments.

Impact of contouring methods on pre-treatment and post-treatment dosimetry for the prediction of tumor control and survival in HCC patients treated with selective internal radiation therapy.

INTRODUCTION: The aim of this study was to evaluate the impact of the contouring methods on dose metrics and their predictive value on tumor control and survival, in both situations of pre-treatment and post-treatment dosimetry, for patients with advanced HCC treated with SIRT. METHODS: Forty-eight patients who underwent SIRT between 2012 and 2020 were retrospectively included in this study. Target volumes were delineated using two methods: MRI-based contours manually drawn by a radiologist and then registered on SPECT/CT and PET/CT via deformable registration (Pre-CMRI and Post-CMRI), 99mTc-MAA-SPECT and 90Y-microspheres-PET 10% threshold contouring (Pre-CSPECT and Post-CPET). The mean absorbed dose (Dm) and the minimal absorbed dose delivered to 70% of the tumor volume (D70) were evaluated with both contouring methods; the tumor-to-normal liver uptake ratio (TNR) was evaluated with MRI-based contours only. Tumor response was assessed using the mRECIST criteria on the follow-up MRIs. RESULTS: No significant differences were found for Dm and TNR between pre- and post-treatment. TNR evaluated with radiologic contours (Pre-CMRI and Post-CMRI) were predictive of tumor control at 6 months on pre- and post-treatment dosimetry (OR 5.9 and 7.1, respectively; p = 0.02 and 0.01). All dose metrics determined with both methods were predictive of overall survival (OS) on pre-treatment dosimetry, but only Dm with MRI-based contours was predictive of OS on post-treatment images with a median of 23 months for patients with a supramedian Dm versus 14 months for the others (p = 0.04). CONCLUSION: In advanced HCC treated with SIRT, Dm and TNR determined with radiologic contours were predictive of tumor control and OS. This study shows that a rigorous clinical workflow (radiologic contours + registration on scintigraphic images) is feasible and should be prospectively considered for improving therapeutic strategy.

[Effect of 99mTc elution in vivo from red cells on red cell volumes measured using autologous 99mTc-labeled red cells: comparison with 51Cr method]. / Effet de l'élution in vivo du technétium sur les volumes globulaires mesurés à l'aide d'hématies autologues marquées au 99mTc : comparaison avec la technique au 51Cr.

The purpose of this work was to compare the measured red-cell volume (RCV) using sodium pertechnétate [RCV-99mTc] compared to the reference technique using sodium radiochromate [RCV-51Cr] and to assess the influence of technetium-99 elution on the RCV-99mTc value. Ten patients had simultaneous measurements of RCV-99mTc and RCV-51Cr. Elution of Tc-99m from red blood cells was 2.9% and led to an average overestimation of RCV-99mTc of 3.7%. The introduction of individual tracer elution rates in the RCV-99mTc calculation corrects this overestimation.

Phospholipidosis and down-regulation of the PI3-K/PDK-1/Akt signalling pathway are vitamin E inhibitable events associated with 7-ketocholesterol-induced apoptosis.

Among the oxysterols accumulating in atherosclerotic plaque, 7-ketocholesterol (7KC) is a potent apoptotic inducer, which favours myelin figure formation and polar lipid accumulation. This investigation performed on U937 cells consisted in characterizing the myelin figure formation process; determining the effects of 7KC on the PI3-K/PDK-1/Akt signalling pathway; evaluating the activities of vitamin E (Vit-E) (alpha-tocopherol) on the formation of myelin figures and the PI3-K/PDK-1/Akt signalling pathway and assessing the effects of PI3-K inhibitors (LY-294002, 3-methyladenine) on the activity of Vit-E on cell death and polar lipid accumulation. The ultrastructural and biochemical characteristics of myelin figures (multilamellar cytoplasmic inclusions rich in phospholipids and 7KC present in acidic vesicles and the reversibility of these alterations) support the hypothesis that 7KC is an inducer of phospholipidosis. This oxysterol also induces important changes in lipid content and/or organization of the cytoplasmic membrane demonstrated with merocyanine 540 and fluorescence anisotropy, a loss of PI3-K activity and dephosphorylation of PDK-1 and Akt. It is noteworthy that Vit-E was able to counteract phospholipidosis and certain apoptotic associated events (caspase activation, lysosomal degradation) to restore PI3-K activity and to prevent PDK-1 and Akt dephosphorylation. When Vit-E was associated with LY-294002 or 3-methyladenine, impairment of 7KC-induced apoptosis was inhibited, and accumulation of polar lipids was less counteracted. Thus, 7KC-induced apoptosis is a PI3-K-dependent event, and Vit-E up- and down-regulates PI3-K activity and phospholipidosis, respectively.

Comparison of fifteen immunoassays for the measurement of serum MUC-1/CA 15-3 in breast cancer patients.

BACKGROUND: Quality control results for serum MUC-1/CA 15-3 assays have always shown large discrepancies. METHODS: This multicentre study of 15 methods (labelled M1-M15) measured coded sera from 35 patients with breast cancer without recurrence (group 1), 46 patients at 1st metastasis (group 2), and 39 patients with advanced metastases (group 3). Results were compared using parametric statistics, ANOVA, principal component analysis, and receiver operating characteristic (ROC) curves. RESULTS: Mean MUC-1/CA 15-3 concentrations varied widely (75.1-303.0 U/mL, 24.8%) among methods. The false positive (FP) rate for group 1 was 8/521 (1.5%); for group 2 and group 3 false negative (FN) results were 21/680 (3.1%) and 11/583 (1.9%), respectively. Using the ROC cut-offs, we found no FPs for group 1 and no FNs for group 3. However, group 2 showed 16 FNs. All p-values for Pearson's correlation were <0.0001 between methods, except for M11. When comparing methods using different antibodies, discordance rates reached a maximum of 15.2%. Principal component analysis revealed a grouping of methods using: CanAg monoclonal antibodies (mAbs) (M2, M7 and M12); Centocor/Fujirebio mAbs (M3-M6, M8-M10, M14-M15) and Biomira mAbs (M1 and M13); and Centocor/Fujirebio mAbs (M11). CONCLUSIONS: Results were more consistent among methods using the same antibody type. Principal component analysis showed that antibody type was the strongest determinant of immunoassay results.

Combination of breast imaging parameters obtained from 18F-FDG PET and CT scan can improve the prediction of breast-conserving surgery after neoadjuvant chemotherapy in luminal/HER2-negative breast cancer.

INTRODUCTION: The luminal/Human Epidermal growth factor Receptor 2 (HER2) negative subtype of breast cancer has low chemo-sensitivity. When neoadjuvant chemotherapy (NAC) is indicated in this subtype, before a possible breast-conserving surgery (BCS), it is more reasonable to target tumor shrinkage than complete pathological tumor response. We aimed to identify breast and tumor 18Fluoro-deoxy-glucose (18F-FDG) PET-CT scan imaging features for the early prediction of BCS after NAC in luminal/HER2 negative subtypes of breast cancer. MATERIAL AND METHODS: Seventy-seven consecutive women with luminal/HER2-negative breast cancer for whom BCS was initially not feasible and NAC was prescribed, to decrease tumor size before surgery, were included retrospectively. An 18F-FDG PET-CT scan exam was performed before and after the first course of NAC. RESULTS: After NAC, 36% (28/77) of women had a mastectomy and 64% (49/77) underwent BCS. Patients with a mastectomy had lower total breast volume (BVtotal) (p = 0.002), lower decrease in Δmetabolic tumor volume (ΔMTV) (p = 0.03) and lower SUVmax2 (p = 0.05). Using ROC Curve analyses to define the optimal predictive threshold of BVtotal (496 cm3) and ΔMTV (-17.1%), 3 subgroups of women with different odds of BCS after treatment were identified (p = 0.001): low, medium and high probability groups (respectively 29%, 62% and 82%). CONCLUSIONS: For patients with Luminal/HER2 negative breast cancer, the combination of the imaging features of the tumor and the mammary gland, obtained with 18F-FDG PET-CT at baseline and after the first cycle of NAC, may allow the physician to evaluate the probability of BCS.

[CA 125 assay in the extension assessment of newly diagnosed breast cancers: why and how?] / Le CA 125 dans le bilan d'extension des cancers du sein nouvellement diagnostiqués : pourquoi et comment ?

CA 125 assay is sometimes combined in practice with the one of CA 15-3 and CEA in the extension assessment of breast cancers. The purpose of this work is to evaluate the contribution of the initial CA 125 as an indicator of distant metastases (DM) or of serous inflammation (SI). This retrospective study concerns a population of 620 patients with breast cancer without metastatic extension (n=325) or metastatic breast cancer (n=295) diagnosed at the Georges-François Leclerc center from 1998 to 2014. Seventy-four patients had SI. We showed that initial CA 125 level is linked to the TNM clinic status, the HER2 status, the nature and the number of metastatic locations, the inflammation of the tumor or serous. The ROC curves and logistic regression analyses show that CA 125 is an independent predictive criterion of DM presence (threshold of 55 kU/L): this is the only positive marker in 7% of patients with DM. At the threshold of 110 kU/L, the CA 125 is the only predictive biologic factor for SI. In conclusion, these data present the independent predictive value of CA 125 on the presence of DM or SI on condition of usinga specific threshold for each of these uses.

FDG PET/CT for prognostic stratification of patients with metastatic breast cancer treated with first line systemic therapy: Comparison of EORTC criteria and PERCIST.

AIM: Evaluate response and predict prognosis of patients with newly diagnosed metastatic breast cancer treated with first line systemic therapy using European Organization for Research and Treatment of Cancer (EORTC) criteria and PET Response Criteria in solid Tumours (PERCIST). METHODS: From December 2006 to August 2013, 57 women with newly diagnosed metastatic breast cancer were retrospectively evaluated. FDG-PET/CT was performed within one month before treatment and repeated after at least 3 cycles of treatment. Metabolic response evaluation was evaluated by two readers according to both EORTC criteria and PERCIST, classifying the patients into 4 response groups: complete metabolic response (CMR), partial metabolic response (PMR), stable metabolic disease (SMD), and progressive metabolic disease (PMD). RESULTS: With EORTC criteria, 22 patients had CMR, 17 PMR, 6 SMD and 12 PMD. With PERCIST, 20 patients had CMR, 15 PMR, 10 SMD and 12 PMD. There was agreement between EORTC and PERCIST in 84% of the patients. By log-rank analysis, metabolic response evaluated with both EORTC criteria and PERCIST was able to predict overall survival (p = 0.028 and 0.002 respectively). CMR patient group had longer median OS than patients in the combined PMR+SMD+PMD group (60 vs 26 months both with EORTC and PERCIST; p = 0.009 and 0.006 respectively). By multivariate analysis, CMR either with EORTC or PERCIST remained an independent predictor of survival. CONCLUSION: Metabolic response evaluation with EORTC criteria and PERCIST gave similar prognostic stratification for metastatic breast cancer treated with a first line of systemic therapy.

Induction of peroxisomal changes in oligodendrocytes treated with 7-ketocholesterol: Attenuation by α-tocopherol.

The involvement of organelles in cell death is well established especially for endoplasmic reticulum, lysosomes and mitochondria. However, the role of the peroxisome is not well known, though peroxisomal dysfunction favors a rupture of redox equilibrium. To study the role of peroxisomes in cell death, 158 N murine oligodendrocytes were treated with 7-ketocholesterol (7 KC: 25-50 µM, 24 h). The highest concentration is known to induce oxiapoptophagy (OXIdative stress + APOPTOsis + autoPHAGY), whereas the lowest concentration does not induce cell death. In those conditions (with 7 KC: 50 µM) morphological, topographical and functional peroxisome alterations associated with modifications of the cytoplasmic distribution of mitochondria, with mitochondrial dysfunction (loss of transmembrane mitochondrial potential, decreased level of cardiolipins) and oxidative stress were observed: presence of peroxisomes with abnormal sizes and shapes similar to those observed in Zellweger fibroblasts, lower cellular level of ABCD3, used as a marker of peroxisomal mass, measured by flow cytometry, lower mRNA and protein levels (measured by RT-qPCR and western blotting) of ABCD1 and ABCD3 (two ATP-dependent peroxisomal transporters), and of ACOX1 and MFP2 enzymes, and lower mRNA level of DHAPAT, involved in peroxisomal ß-oxidation and plasmalogen synthesis, respectively, and increased levels of very long chain fatty acids (VLCFA: C24:0, C24:1, C26:0 and C26:1, quantified by gas chromatography coupled with mass spectrometry) metabolized by peroxisomal ß-oxidation. In the presence of 7 KC (25 µM), slight mitochondrial dysfunction and oxidative stress were found, and no induction of apoptosis was detected; however, modifications of the cytoplasmic distribution of mitochondria and clusters of mitochondria were detected. The peroxisomal alterations observed with 7 KC (25 µM) were similar to those with 7 KC (50 µM). In addition, data obtained by transmission electron microcopy and immunofluorescence microscopy by dual staining with antibodies raised against p62, involved in autophagy, and ABCD3, support that 7 KC (25-50 µM) induces pexophagy. 7 KC (25-50 µM)-induced side effects were attenuated by α-tocopherol but not by α-tocotrienol, whereas the anti-oxidant properties of these molecules determined with the FRAP assay were in the same range. These data provide evidences that 7 KC, at concentrations inducing or not cell death, triggers morphological, topographical and functional peroxisomal alterations associated with minor or major mitochondrial changes.

Patterns of loss of heterozygosity in breast carcinoma during neoadjuvant chemotherapy.

There is evidence indicating that resistance to some chemotherapy drugs is related to enhanced repair of DNA lesions. Microsatellite instability (MSI) and loss of heterozy-gosity (LOH) reflect genetic instability and are associated with specific DNA repair pathways. Despite the strong implication of genetic instability in breast cancer its association with chemotherapy is unknown. Thus, we analyzed microsatellite alterations with 12 markers in locally advanced breast carcinomas in relation to neoadjuvant epirubicin-cyclophosphamide-containing chemotherapy (FEC-100) and compared it to a docetaxol-based (Tax-Epi) regimen. Samples were obtained before, during and after treatments. In pre-treated samples, MSI was detected only in 2 cases (7%) whereas LOH was found in 23 of the 34 (68%) carcinomas including 10 belonging to the FEC-100 group and 13 to Tax-Epi one. LOH frequency decreased from the first course of both regimens, but differences between the patterns of LOH during treatment were found. Persistent LOH was more frequent in FEC-100 group (71% vs. 41%) that was detected only in biopsies belonging to non-responder patients. Persistent LOH were clustered at particular loci located at regions containing common fragile sites (FHIT and FRA6E). Analysis of baseline LOH with 6 markers located at 3p indicates discontinuous patterns reflecting double-strand break (DSB) lesions. These results agree with a drug-dependent link between genetic instability and chemoresistance and show that FEC-100 treatment is associated with DSB accumulation manifested as LOH in tumor cells resistant to chemotherapy in breast carcinoma.

Overexpression of caspase-3s splice variant in locally advanced breast carcinoma is associated with poor response to neoadjuvant chemotherapy.

PURPOSE: CASP-3 gene gives rise, by alternative splicing to a caspase-3s variant, to the antagonist apoptotic property of caspase-3. Deregulation of splicing in tumor cells favoring the expression of antiapoptotic variants has been reported to contribute to both tumorigenesis and chemoresistance. Thus, we investigated the role of caspase-3 and its splice variant in breast cancer cells. EXPERIMENTAL DESIGN: Breast tumor cell lines deficient (MCF-7) and proficient (HBL100) for CASP-3 gene were transfected with each transcript and were characterized for their apoptotic response to cyclophosphamide. Expression of the two transcripts were measured by reverse transcription-PCR in 130 breast carcinomas, including 90 locally advanced tumors treated with neoadjuvant chemotherapy containing cyclophosphamide, epirubicine, and 5-fluorouracil. RESULTS: Overexpression of caspase-3s variant in caspase-3-transfected cell lines significantly inhibits apoptosis induced by cyclophosphamide (P < 0.0001 for both cell lines). In breast tissues, only caspase-3 levels were higher in carcinomas than in corresponding adjacent normal tissues (P = 0.0396). Locally advanced carcinomas with high levels of caspase-3 (P < 0.0001) and weak levels of caspase-3s (P = 0.0248) were more sensitive to treatment. Therefore, increase in caspase-3s/caspase3 ratio expression was significantly associated with chemoresistance (P = 0.01). Logistic univariate and multivariate analyses realized according to pathologic response confirm that increased caspase-3s expression was indicative of chemoresistance (P = 0.012 and P = 0.026, respectively). CONCLUSIONS: The results agree with an antagonist function between the two transcripts of caspase-3 and show that their ratio of expression levels may define a subset of locally advanced breast cancer patients who are more likely to benefit from neoadjuvant cyclophosphamide-containing chemotherapy.