Chest CT scan plus x-ray versus chest x-ray for the follow-up of completely resected non-small-cell lung cancer (IFCT-0302): a multicentre, open-label, randomised, phase 3 trial.

BACKGROUND: Even after resection of early-stage non-small-cell lung cancer (NSCLC), patients have a high risk of developing recurrence and second primary lung cancer. We aimed to assess efficacy of a follow-up approach including clinic visits, chest x-rays, chest CT scans, and fibre-optic bronchoscopy versus clinical visits and chest x-rays after surgery for resectable NSCLC. METHODS: In this multicentre, open-label, randomised, phase 3 trial (IFCT-0302), patients aged 18 years or older and after complete resection of pathological stage I-IIIA NSCLC according to the sixth edition of the TNM classification were enrolled within 8 weeks of resection from 122 hospitals and tertiary centres in France. Patients were randomly assigned (1:1) to CT-based follow-up (clinic visits, chest x-rays, thoraco-abdominal CT scans, and fibre-optic bronchoscopy for non-adenocarcinoma histology) or minimal follow-up (visits and chest x-rays) after surgery for NSCLC, by means of a computer-generated sequence using the minimisation method. Procedures were repeated every 6 months for the first 2 years and yearly until 5 years. The primary endpoint was overall survival analysed in the intention-to-treat population. Secondary endpoints, also analysed in the intention-to-treat population, included disease-free survival. This trial is registered with ClinicalTrials.gov, NCT00198341, and is active, but not enrolling. FINDINGS: Between Jan 3, 2005, and Nov 30, 2012, 1775 patients were enrolled and randomly assigned to a follow-up group (888 patients to the minimal follow-up group; 887 patients to the CT-based follow-up group). Median overall survival was not significantly different between follow-up groups (8·5 years [95% CI 7·4-9·6] in the minimal follow-up group vs 10·3 years [8·1-not reached] in the CT-based follow-up group; adjusted hazard ratio [HR] 0·95, 95% CI 0·83-1·10; log-rank p=0·49). Disease-free survival was not significantly different between follow-up groups (median not reached [95% CI not estimable-not estimable] in the minimal follow-up group vs 4·9 [4·3-not reached] in the CT-based follow-up group; adjusted HR 1·14, 95% CI 0·99-1·30; log-rank p=0·063). Recurrence was detected in 246 (27·7%) of 888 patients in the minimal follow-up group and in 289 (32·6%) patients of 887 in the CT-based follow-up group. Second primary lung cancer was diagnosed in 27 (3·0%) patients in the minimal follow-up group and 40 patients (4·5%) in the CT-based follow-up group. No serious adverse events related to the trial procedures were reported. INTERPRETATION: The addition of thoracic CT scans during follow-up, which included clinic visits and chest x-rays after surgery, did not result in longer survival among patients with NSCLC. However, it did enable the detection of more cases of early recurrence and second primary lung cancer, which are more amenable to curative-intent treatment, supporting the use of CT-based follow-up, especially in countries where lung cancer screening is already implemented, alongside with other supportive measures. FUNDING: French Health Ministry, French National Cancer Institute, Weisbrem-Benenson Foundation, La Ligue Nationale Contre Le Cancer, and Lilly Oncology. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.

Association between lung cancer somatic mutations and occupational exposure in never-smokers.

Occupational exposure constitutes a common risk factor for lung cancer. We observed molecular alterations in 73% of never-smokers, 35% of men and 8% of women were exposed to at least one occupational carcinogen. We report herein associations between molecular patterns and occupational exposure.BioCAST was a cohort study of lung cancer in never-smokers that reported risk factor exposure and molecular patterns. Occupational exposure was assessed via a validated 71-item questionnaire. Patients were categorised into groups that were unexposed and exposed to polycyclic aromatic hydrocarbons (PAH), asbestos, silica, diesel exhaust fumes (DEF), chrome and paints. Test results were recorded for EGFR, KRAS, HER2, BRAF and PIK3 mutations, and ALK alterations.Overall, 313 out of 384 patients included in BioCAST were analysed. Asbestos-exposed patients displayed a significantly lower rate of EGFR mutations (20% versus 44%, p=0.033), and a higher rate of HER2 mutations (18% versus 4%, p=0.084). ALK alterations were not associated with any occupational carcinogens. The DEF-exposed patients were diagnosed with a BRAF mutation in 25% of all cases. Chrome-exposed patients exhibited enhanced HER2 and PIK3 mutation frequency.Given its minimal effects in the subgroups, we conclude that occupational exposure slightly affects the molecular pattern of lung cancers in never-smokers. In particular, asbestos-exposed patients have a lower chance of EGFR mutations.

No impact of passive smoke on the somatic profile of lung cancers in never-smokers.

EGFR and HER2 mutations and ALK rearrangement are known to be related to lung cancer in never-smokers, while KRAS, BRAF and PIK3CA mutations are typically observed among smokers. There is still debate surrounding whether never-smokers exposed to passive smoke exhibit a "smoker-like" somatic profile compared with unexposed never-smokers. Passive smoke exposure was assessed in the French BioCAST/IFCT-1002 never-smoker lung cancer cohort and routine molecular profiles analyses were compiled. Of the 384 patients recruited into BioCAST, 319 were tested for at least one biomarker and provided data relating to passive smoking. Overall, 219 (66%) reported having been exposed to passive smoking. No significant difference was observed between mutation frequency and passive smoke exposure (EGFR mutation: 46% in never exposed versus 41% in ever exposed; KRAS: 7% versus 7%; ALK: 13% versus 11%; HER2: 4% versus 5%; BRAF: 6% versus 5%; PIK3CA: 4% versus 2%). We observed a nonsignificant trend for a negative association between EGFR mutation and cumulative duration of passive smoke exposure. No association was found for other biomarkers. There is no clear association between passive smoke exposure and somatic profile in lifelong, never-smoker lung cancer.

The codon 72 polymorphic variants of p53 have markedly different apoptotic potential.

The gene TP53, encoding p53, has a common sequence polymorphism that results in either proline or arginine at amino-acid position 72. This polymorphism occurs in the proline-rich domain of p53, which is necessary for the protein to fully induce apoptosis. We found that in cell lines containing inducible versions of alleles encoding the Pro72 and Arg72 variants, and in cells with endogenous p53, the Arg72 variant induces apoptosis markedly better than does the Pro72 variant. Our data indicate that at least one source of this enhanced apoptotic potential is the greater ability of the Arg72 variant to localize to the mitochondria; this localization is accompanied by release of cytochrome c into the cytosol. These data indicate that the two polymorphic variants of p53 are functionally distinct, and these differences may influence cancer risk or treatment.

Hepatocyte-derived cultured cells with unusual cytoplasmic keratin-rich spheroid bodies.

Cytoplasmic inclusions are found in a variety of diseases that are characteristic morphological features of several hepatic, muscular and neurodegenerative disorders. They display a predominantly filamentous ultrastructure that is also observed in malignant rhabdoid tumor (MRT). A cellular clone containing an intracytoplasmic body was isolated from hepatocyte cell culture, and in the present study we examined whether this body might be related or not to Mallory-Denk body (MDB), a well characterized intracytoplasmic inclusion, or whether this cellular clone was constituted by malignant rhabdoid tumor cells. The intracytoplasmic body was observed in electron microscopy (EM), confocal immunofluorescence microscopy and several proteins involved in the formation of its structure were identified. Using light microscopy, a spheroid body (SB) described as a single regular-shaped cytoplasmic body was observed in cells. During cytokinesis, the SB was disassembled and reassembled in a way to reconstitute a unique SB in each progeny cell. EM examination revealed that the SB was not surrounded by a limiting membrane. However, cytoplasmic filaments were concentrated in a whorled array. These proteins were identified as keratins 8 and 18 (K8/K18), which formed the central core of the SB surrounded by a vimentin cage-like structure. This structure was not related to Mallory-Denk body or aggresome since no aggregated proteins were located in SB. Moreover, the structure of SB was not due to mutations in the primary sequence of K8/K18 and vimentin since no difference was observed in the mRNA sequence of their genes, isolated from Huh-7 and Huh-7w7.3 cells. These data suggested that cellular factor(s) could be responsible for the SB formation process. Aggregates of K18 were relocated in the SB when a mutant of K18 inducing disruption of K8/K18 IF network was expressed in the cellular clone. Furthermore, the INI1 protein, a remodeling-chromatin factor deficient in rhabdoid cells, which contain a spheroid perinuclear inclusion body, was found in our cellular clone. In conclusion, our data suggest that Huh-7w7.3 cells constitute an excellent model for determining the cellular factor(s) involved in the process of spheroid perinuclear body formation.

Tailoring maintenance chemotherapy upon response to induction chemotherapy as compared with pemetrexed continuation maintenance in advanced non-squamous NSCLC patients: Results of the IFCT-GFPC-1101 multicenter randomized phase III trial.

BACKGROUND: Benefit from maintenance in advanced non-squamous non-small cell lung cancer (NS-NSCLC) might favor switch maintenance after disease stabilization (SD) and continuation after objective response (OR). This trial assessed a maintenance strategy conditioned by response to cisplatin-gemcitabine (CG) with G continuation for patients with OR or switch to pemetrexed (P) for patients with SD as compared with a control arm based on the Paramount regimen. METHODS: Eligibility criteria: age 18-70 years, ECOG PS 0-1, untreated stage IV NS-NSCLC without EGFR or ALK alteration, ineligibility to bevacizumab. Patients were randomized 1:1 to receive either CG (4 cycles) followed by G maintenance in case of OR followed by P at progression, or switch to P for patients with SD, or 4 cycles of CP followed by P (control arm). Primary endpoint: overall Survival. RESULTS: Between 2012 and 2016, 932 patients were randomized (CG: 467, CP: 465) with well-balanced characteristics. 257 patients (56.7%) in the CG arm received maintenance (G: 142, P: 113) versus 277 patients (59.7%) in the CP arm. Median number of maintenance cycles was 5 for G and P (CG induction) and 4 for P (CP induction). OS adjusted HR was 0.97 (95% CI 0.84, 1.13; p = 0.71) with a median of 10.9 months (CG) versus 10.4 (CP). HR for PFS was 0.95 (95% CI 0.83, 1.09; p = 0.45) with a median of 4.8 months for CG versus 4.5 for CP. Safety profile was as expected. CONCLUSIONS: Adapting maintenance strategy according to response to induction chemotherapy does not improve patient outcome. CLINICAL TRIAL INFORMATION: NCT01631136.

Mitochondrial p53 activates Bak and causes disruption of a Bak-Mcl1 complex.

The tumour suppressor activity of the p53 protein has been explained by its ability to induce apoptosis in response to a variety of cellular stresses. Thus, understanding the mechanism by which p53 functions in the execution of cell death pathways is of considerable importance in cancer biology. Recent studies have indicated that p53 has a direct signalling role at mitochondria in the induction of apoptosis, although the mechanisms involved are not completely understood. Here we show that, after cell stress, p53 interacts with the pro-apoptotic mitochondrial membrane protein Bak. Interaction of p53 with Bak causes oligomerization of Bak and release of cytochrome c from mitochondria. Notably, we show that formation of the p53-Bak complex coincides with loss of an interaction between Bak and the anti-apoptotic Bcl2-family member Mcl1. These results are consistent with a model in which p53 and Mcl1 have opposing effects on mitochondrial apoptosis by interacting with, and modulating the activity of, the death effector Bak.

Bacterial infection profiles in lung cancer patients with febrile neutropenia.

BACKGROUND: The chemotherapy used to treat lung cancer causes febrile neutropenia in 10 to 40% of patients. Although most episodes are of undetermined origin, an infectious etiology can be suspected in 30% of cases. In view of the scarcity of data on lung cancer patients with febrile neutropenia, we performed a retrospective study of the microbiological characteristics of cases recorded in three medical centers in the Picardy region of northern France. METHODS: We analyzed the medical records of lung cancer patients with neutropenia (neutrophil count < 500/mm(3)) and fever (temperature > 38.3°C). RESULTS: The study included 87 lung cancer patients with febrile neutropenia (mean age: 64.2). Two thirds of the patients had metastases and half had poor performance status. Thirty-three of the 87 cases were microbiologically documented. Gram-negative bacteria (mainly enterobacteriaceae from the urinary and digestive tracts) were identified in 59% of these cases. Staphylococcus species (mainly S. aureus) accounted for a high proportion of the identified Gram-positive bacteria. Bacteremia accounted for 60% of the microbiologically documented cases of fever. 23% of the blood cultures were positive. 14% of the infections were probably hospital-acquired and 14% were caused by multidrug-resistant strains. The overall mortality rate at day 30 was 33% and the infection-related mortality rate was 16.1%. Treatment with antibiotics was successful in 82.8% of cases. In a multivariate analysis, predictive factors for treatment failure were age >60 and thrombocytopenia < 20000/mm(3). CONCLUSION: Gram-negative species were the most frequently identified bacteria in lung cancer patients with febrile neutropenia. Despite the success of antibiotic treatment and a low-risk neutropenic patient group, mortality is high in this particular population.

Switch maintenance chemotherapy versus observation after carboplatin and weekly paclitaxel doublet chemotherapy in elderly patients with advanced non-small cell lung cancer: IFCT-1201 MODEL trial.

PURPOSE: Maintenance chemotherapy is a reasonable choice for patients with metastatic non-small cell lung carcinoma (NSCLC) not progressing after induction therapy with a platinum-based doublet. Nevertheless, there have been no studies dedicated to elderly patients. PATIENTS AND METHODS: We conducted a randomised trial in patients aged 70-89 years, with advanced NSCLC (with neither EGFR mutation nor ALK rearrangement), who had not progressed after four cycles of monthly carboplatin and weekly paclitaxel in order to compare maintenance with either pemetrexed (500 mg/m2 d1, 22) in patients with non-squamous cell carcinoma or gemcitabine (1,150 mg/m2 d1, 8, 22) in squamous cell carcinoma to simple observation. The patients were required to have a performance status (PS) 0-2, mini-mental score >23, and creatinine clearance ≥45 mL/min. The primary end-point was overall survival (OS). RESULTS: 632 patients were enrolled from May 2013 to October 2016. Of the 328 (52.3%) patients randomised after induction therapy, 166 patients were assigned to the observation arm, versus 162 to the switch maintenance arm, 119 of whom received pemetrexed and 43 gemcitabine. The median OS from randomisation was 14.1 months (95% confidence interval [CI]: 12.0-17.0) in the observation arm and 14 months (95% CI: 10.9-16.9) in the maintenance arm (p = 0.72). The median progression-free survival (PFS) from randomisation was 2.7 months (95% CI: 2.6-3.1) in the observation arm versus 5.7 months (95% CI: 4.8-7.1) in the maintenance arm (p < 0.001). CONCLUSION: Switch maintenance therapy significantly prolonged PFS but not OS and, thus, should not be proposed to elderly patients with advanced NSCLC.

Weekly paclitaxel plus bevacizumab versus docetaxel as second- or third-line treatment in advanced non-squamous non-small-cell lung cancer: Results of the IFCT-1103 ULTIMATE study.

PURPOSE: Second-line chemotherapy regimens have demonstrated poor benefit after failure of platinum-based chemotherapy in advanced non-squamous non-small-cell lung cancer (nsNSCLC). METHODS: In this multicentre, open-label phase III trial, patients with advanced nsNSCLC treated with one or two prior lines, including one platinum-based doublet, were centrally randomised to receive 90 mg/m2 of paclitaxel (D1, D8, D15) plus 10 mg/kg of bevacizumab (D1, D15) every 28 days or docetaxel (75 mg/m2) every 21 days; crossover was allowed after disease progression. Primary end-point was progression-free survival (PFS). ClinicalTrials.gov registration number: NCT01763671. RESULTS: One hundred sixty six patients were randomised (paclitaxel plus bevacizumab: 111, docetaxel: 55). The median PFS was longer in patients receiving paclitaxel plus bevacizumab than in patients receveing docetaxel [5·4 months versus 3·9 months, adjusted hazard ratio (HR) 0·61 (95% confidence interval [CI]: 0·44-0·86); p = 0·005]. Objective response rates (ORRs) were 22·5% (95% CI: 14·8-30·3) and 5·5% (95% CI: 0·0-11·5) (p = 0·006), respectively. Median overall survivals were similar (adjusted HR 1·17; p = 0·50). Crossover occurred in 21 of 55 (38·2%) docetaxel-treated patients. Grade III-IV adverse events (AEs) were reported in 45·9% and 54·5% of patients treated with paclitaxel and bevacizumab or docetaxel, respectively (p = NS), including neutropenia (19·3% versus 45·4%), neuropathy (8·3% versus 0·0%) and hypertension (7·3% versus 0·0%). Three patients died due to treatment-related AEs (1·8% in each group). CONCLUSION: Weekly paclitaxel plus bevacizumab as second- or third-line improves PFS and ORR compared with docetaxel in patients with nsNSCLC, with an acceptable safety profile. These results place weekly paclitaxel plus bevacizumab as a valid option in this population. CLINICAL TRIALS REGISTRATION NUMBER: ClinicalTrials.gov Identifier: NCT01763671.

Expression of galectin-3 in the tumor immune response in colon cancer.

The role of tumor-associated macrophages (TAMs) is controversial. Although most studies on different cancer types associate them with a poorer prognosis, interestingly in colon cancer, most articles indicate that TAMs prevent tumor development; patients with high TAMs have better prognosis and survival rate. M1-polarized macrophages produce high level of tumor necrosis factor-alpha, interleukin-1 beta or reactive oxygen species, which can effectively kill susceptible tumor cells. In contrast, M2-polarized macrophages can secrete different factors that promote tumor cell growth and survival or favor angiogenesis and tissue invasion. Considering the beneficial role of TAMs in colon cancer, we speculated that they may not display the M2 polarization commonly observed in tumor microenvironment, but rather develop M1 properties. Therefore, we used an in vitro model to analyze the effects of supernatants from M1-polarized macrophages on DLD-1 colon cancer cells. Our data indicate that the conditioned medium from LPS-activated macrophages (CM-LAM) contains a high level of granulocyte-macrophage colony-stimulating factor, interleukins-1 beta, -6, -8 and tumor necrosis factor-alpha, and that it exerts a marked growth inhibitory activity on DLD-1 cells. Prolonged exposure to CM-LAM results in cell death by apoptosis. Such exposure to CM-LAM leads to the modulation of gal-3 expression: we observed a marked downregulation of gal-3 mRNA and protein expression following CM-LAM treatment. We also describe that the knockdown of gal-3 sensitizes DLD-1 cells to CM-LAM. These data suggest an involvement of gal-3 in the response of colon cancer cells to proinflammatory stimuli, such as the conditioned medium from activated macrophages.

Serine 392 phosphorylation modulates p53 mitochondrial translocation and transcription-independent apoptosis.

The tumor suppressor p53 is a key regulator of apoptosis induced by various cellular stresses. p53 can induce apoptosis by two mechanisms. First, p53 acts as a transcription factor inducing and repressing pro-apoptotic and anti-apoptotic targets genes, respectively. Second, p53 is able to translocate to the mitochondria, where it interacts with BCL-2 family members to induce membrane permeabilization and cytochrome c release. p53 transcriptional activity is regulated by a set of post-translational modifications that have been well documented. However, how these modifications impact the direct mitochondrial pathway of death remain poorly understood. In this study, we focused on the role of serine 392 phosphorylation in the control of p53-dependent apoptosis. We used CRISPR/Cas9 genome editing to substitute serine 392 by a non-phosphorylatable alanine in HCT-116 colon carcinoma cells. The S392A mutant displayed normal transcriptional activity following genotoxic stress, but markedly impaired ability to localize to mitochondria. The decreased mitochondrial localization of the S392A mutant correlated with a lower ability to induce apoptosis. Confirmatory observations were made following enforced expression of the S392A p53 mutant or a phospho-mimetic S392E mutant in H1299 lung carcinoma cells. Our observations support the premise that serine 392 phosphorylation of p53 influences its mitochondrial translocation and transcription-independent apoptotic function.

Phase II study assessing the benefit of cisplatin re-introduction (stop-and-go strategy) in patients with advanced non-squamous non-small cell lung cancer: the IFCT-1102 BUCiL study (a Better Use of Cisplatin in Lung cancer).

INTRODUCTION: This single-arm phase II trial aimed to evaluate a stop-and-go strategy with cisplatin-based chemotherapy and bevacizumab in advanced non-squamous non-small cell lung cancer (NSCLC). METHODS: Patients were initially treated with three cycles of pemetrexed, cisplatin plus bevacizumab (sequence 1) followed by bevacizumab maintenance and after progression, re-introduction of three cycles of pemetrexed, cisplatin plus bevacizumab (sequence 2) and pemetrexed plus bevacizumab maintenance. The primary endpoint was the proportion of patients with advanced non-squamous NSCLC receiving the complete sequence 2 without platinum dose reduction (hypothesis ≥75%). RESULTS: 120 patients with performance status ≤1 were included. Of 113 patients evaluable for efficacy, 65 (57.5%) entered in sequence 2 and 56 (86%) received the three planned cycles including 37 (56.9%, 95% CI 45.1 to 73.6) without platinum dose reduction. The median progression-free survival 1 (PFS1; inclusion to progression 1) was 5.6 months (95% CI 5.0 to 6.3) and median PFS2 (progression 1 to progression 2) was 6.8 months (95% CI 5.8 to 8.8). The median disease control duration (PFS1+PFS2; n=65) was 12.4 months (95% CI 11.2 to 14.9). The median overall survival was 17.7 months (95% CI 13.1 to 21.6) and 20.5 months (95% CI 16.9 to 26.9) for patients reaching the sequence 2 (n=65). CONCLUSION: Although the stringent primary endpoint was not met, this stop-and-go strategy with platinum-based chemotherapy plus bevacizumab continuation beyond progression compares favourably with standard schedule, deserving to be further studied in advanced non-squamous NSCLC.

2,2,2-Trichloro-N-({2-[2-(dimethylamino)ethyl]-1,3-dioxo-2,3-dihydro-1H-benzo[de]isoquinolin- 5-yl}carbamoyl)acetamide (UNBS3157), a novel nonhematotoxic naphthalimide derivative with potent antitumor activity.

Amonafide (1), a naphthalimide which binds to DNA by intercalation and poisons topoisomerase IIalpha, has demonstrated activity in phase II breast cancer trials, but has failed thus far to enter clinical phase III because of dose-limiting bone marrow toxicity. Compound 17 (one of 41 new compounds synthesized) is a novel anticancer naphthalimide with a distinct mechanism of action, notably inducing autophagy and senescence in cancer cells. Compound 17 (2,2,2-trichloro-N-({2-[2-(dimethylamino)ethyl]-1,3-dioxo-2,3-dihydro-1H-benzo[de]isoquinolin-5-yl}carbamoyl)acetamide (UNBS3157)) was found to have a 3-4-fold higher maximum tolerated dose compared to amonafide and not to provoke hematotoxicity in mice at doses that display significant antitumor effects. Furthermore, 17 has shown itself to be superior to amonafide in vivo in models of (i) L1210 murine leukemia, (ii) MXT-HI murine mammary adenocarcinoma, and (iii) orthotopic models of human A549 NSCLC and BxPC3 pancreatic cancer. Compound 17, therefore, merits further investigation as a potential anticancer agent.

The new face of non-small-cell lung cancer in men: Results of two French prospective epidemiological studies conducted 10 years apart.

OBJECTIVES: To evaluate the impact of epidemiological changes observed in 10 years in men with NSCLC on 1-year mortality; to compare prognosis factors of 1-year mortality according to gender. MATERIAL AND METHODS: The French College of General Hospital Respiratory Physicians conducted two prospective epidemiological multicentre studies at a 10-year interval (KBP-2000-CPHG and KBP-2010-CPHG). These studies included all adult patients with primary lung cancer histologically or cytologically diagnosed between 1(st) January and 31(st) December for the years 2000 and 2010, managed in the pneumology department of the participating hospitals. A standardised form was completed for each patient. A steering committee checked recruitment exhaustiveness. Vital status 1 year after diagnosis was collected. RESULTS: In 2000 and 2010 respectively, 137 and 104 centres included 3921 and 4597 men and 748 and 1486 women with NSCLC. In 2010 compared to 2000, male patients were older but had better performance status (PS); they were less frequently ever-smokers and heavy smokers; their cancer (usually diagnosed at advanced stage) was more often adenocarcinoma (p<0.0001). In 10 years, 1-year mortality has significantly decreased in men (from 61.2% to 56.6%, p<0.0001) and in women (from 58.1% to 50.9%, p<0.0001), but remained higher in men than in women leading to increased difference between men and women. Decreased 1-year mortality remained statistically significant after adjustment on age, PS, smoking, and histology (men: OR=0.81, 95% CI=0.73-0.90, p<0.0001; women: 0.71, 0.57-0.88, p<0.002). Active smoking was not a prognosis factor in men (OR=1.04, CI=0.79-1.37, p=0.78); age (>75 years) had less impact on mortality in men than in women (men: OR=1.43, CI=1.22-1.67, p ≤ 0.0001; women: OR=2.32, CI=1.71-3.15; p<0.0001). CONCLUSIONS: The improved 1-year survival in 2010 as compared with 2000 was independent of age, smoking, PS, and histology, suggesting that it reflected new treatment and strategy efficacy. One-year mortality remains higher in men than in women.

Decrease of mitochondrial p53 during late apoptosis is linked to its dephosphorylation on serine 20.

Following a genotoxic stress, the tumor suppressor p53 translocates to mitochondria to take part in direct induction of apoptosis, via interaction with BCL-2 family members such as BAK and BAX. We determined the kinetics of the mitochondrial translocation of p53 in HCT-116 and PA-1 cells exposed to different genotoxic stresses (doxorubicin, camptothecin, UVB). This analysis revealed an early escalation in the amount of mitochondrial p53, followed by a peak amount and a decrease of mitochondrial p53 at later time points. We show that the serine 20 phosphorylated form of p53 is present at the mitochondria and that the decrease of p53 mitochondrial level during late apoptosis correlates with a decrease of Ser-20 phosphorylation. Moreover, the S20A p53 mutant translocates well to mitochondria after a genotoxic stress but its mitochondrial localization is very low during late apoptosis when compared to wt p53. The S20A mutant also appears to be compromised for interaction with BAK. We propose here that the level of serine 20 phosphorylation is influential on p53 mitochondrial localization during late apoptosis. Additionally, we report the presence of a new ≃45 kDa caspase-cleaved fragment of p53 in the cytosolic and mitochondrial fractions of apoptotic cells.

Resveratrol induces DNA damage in colon cancer cells by poisoning topoisomerase II and activates the ATM kinase to trigger p53-dependent apoptosis.

Resveratrol (trans-3,4',5-trihydroxystilbene) is a natural polyphenol synthesized by various plants such as grape vine. Resveratrol (RSV) is a widely studied molecule, largely for its chemopreventive effect in different mouse cancer models. We propose a mechanism underlying the cytotoxic activity of RSV on colon cancer cells. Our data show that resveratrol induces apoptosis, as observed by the cleavage of PARP-1 and chromatin condensation. We show that the tumor suppressor p53 is activated in response to RSV and participates to the apoptotic process. Additionally, we show that HCT-116 p53 wt colon carcinoma cells are significantly more sensitive than HCT-116 p53-/- cells to RSV. RSV induces DNA damage including double strand breaks, as evidenced by the presence of multiple γ-H2AX foci in 50% of cells after a 24 h treatment with 25 µM RSV. The formation of DNA damage does not appear to rely on a pro-oxidant effect of the molecule, inhibition of topoisomerase I, or DNA intercalation. Rather, we show that DNA damage is the consequence of type II topoisomerase poisoning. Exposure of HCT-116 cells to RSV leads to activation of the Ataxia Telangiectasia Mutated (ATM) kinase, and ATM is required to activate p53.

The obesity-associated transcription factor ETV5 modulates circulating glucocorticoids.

The transcription factor E-twenty-six version 5 (ETV5) has been linked with obesity in genome-wide association studies. Moreover, ETV5-deficient mice (knockout; KO) have reduced body weight, lower fat mass, and are resistant to diet-induced obesity, directly linking ETV5 to the regulation of energy balance and metabolism. ETV5 is expressed in hypothalamic brain regions that regulate both metabolism and HPA axis activity, suggesting that ETV5 may also modulate HPA axis function. In order to test this possibility, plasma corticosterone levels were measured in ETV5 KO and wildtype (WT) mice before (pre-stress) and after (post-stress) a mild stressor (intraperitoneal injection). ETV5 deficiency increased both pre- and post-stress plasma corticosterone, suggesting that loss of ETV5 elevated glucocorticoid tone. Consistent with this idea, ETV5 KO mice have reduced thymus weight, suggestive of increased glucocorticoid-induced thymic involution. ETV5 deficiency also decreased the mRNA expression of glucocorticoid receptor (GR), mineralocorticoid receptor (MR), and vasopressin receptor 1A in the hypothalamus, without altering vasopressin, corticotropin-releasing hormone, or oxytocin mRNA expression. In order to test whether reduced MR and GR expression affected glucocorticoid negative feedback, a dexamethasone suppression test was performed. Dexamethasone reduced plasma corticosterone in both ETV5 KO and WT mice, suggesting that glucocorticoid negative feedback was unaltered by ETV5 deficiency. In summary, these data suggest that the obesity-associated transcription factor ETV5 normally acts to diminish circulating glucocorticoids. This might occur directly via ETV5 actions on HPA-regulatory brain circuitry, and/or indirectly via ETV5-induced alterations in metabolic factors that then influence the HPA axis.

Overexpression of apolipoprotein J in human fibroblasts protects against cytotoxicity and premature senescence induced by ethanol and tert-butylhydroperoxide.

Human diploid fibroblasts (HDFs) exposed to subcytotoxic stresses under H2O2, tert-butylhydroperoxide (t-BHP), and ethanol (EtOH) undergo stress-induced premature senescence (SIPS) characterized by many biomarkers of HDFs replicative senescence. Among these biomarkers are a growth arrest, an increase in the senescence-associated beta-galactosidase activity, a senescent morphology, an overexpression of p21waf-1 and the subsequent inability to phosphorylate pRb, the presence of the common 4977-bp mitochondrial deletion, and an increase in the steady-state level of several senescence-associated genes such as apolipoprotein J (apo J). Apo J has been described as a survival gene against cytotoxic stress. In order to study whether apo J would be protective against cytotoxicity SIPS and replicative senescence in human fibroblasts, a full-length complementary deoxyribonucleic acid of apo J was transfected into WI-38 HDFs and SV40-transformed WI-38 HDFs. The overexpression of apo J resulted in an increased cell survival after t-BHP and EtOH stresses at cytotoxic concentrations. In addition, when WI-38 HDFs were exposed to 5 subcytotoxic stresses with EtOH or t-BHP, in conditions that were previously shown to induce SIPS, a lower induction of 2 biomarkers of SIPS was observed in HDFs overexpressing apo J. No effect of apo J overexpression was observed on the proliferative life span of HDFs, even if apo J overexpression triggered osteonectin (SPARC) overexpression, which was shown to decrease the mitogenic potential of platelet-derived growth factor but not of other common growth-inducing conditions. Apo J senescence-related overexpression is proposed to have antiapoptotic rather than antiproliferative effects.

Methods to study p53-repressed promoters.

There is substantial evidence in the literature that, in addition to functioning as an activator of transcription, the p53 tumor suppressor protein can also function as a sequence-specific transcriptional repressor of a separate set of genes. However, elucidation of the mechanism whereby p53 functions as a transcriptional repressor has been obscured by the use of artificial assays to measure this activity; these assays include transient transfection analyses, where both p53 and target promoters are overexpressed. This chapter describes alternative approaches for the definition of sequence elements that mediate transcriptional repression by p53. These include the McKay (immunobinding) assay, which measures the in vitro binding of large fragments of DNA, as well as chromatin immunoprecipitations (ChIPs), which measure in vivo binding. The use of such assays should better define the mechanism of transcriptional repression by p53 and should aid in the elucidation of the contribution of this activity to p53-dependent growth arrest and programmed cell death (apoptosis).