Search for γ-Ray Line Signals from Dark Matter Annihilations in the Inner Galactic Halo from 10 Years of Observations with H.E.S.S.

Spectral lines are among the most powerful signatures for dark matter (DM) annihilation searches in very-high-energy γ rays. The central region of the Milky Way halo is one of the most promising targets given its large amount of DM and proximity to Earth. We report on a search for a monoenergetic spectral line from self-annihilations of DM particles in the energy range from 300 GeV to 70 TeV using a two-dimensional maximum likelihood method taking advantage of both the spectral and spatial features of the signal versus background. The analysis makes use of Galactic center observations accumulated over ten years (2004-2014) with the H.E.S.S. array of ground-based Cherenkov telescopes. No significant γ-ray excess above the background is found. We derive upper limits on the annihilation cross section ⟨σv⟩ for monoenergetic DM lines at the level of 4×10^{-28} cm^{3} s^{-1} at 1 TeV, assuming an Einasto DM profile for the Milky Way halo. For a DM mass of 1 TeV, they improve over the previous ones by a factor of 6. The present constraints are the strongest obtained so far for DM particles in the mass range 300 GeV-70 TeV. Ground-based γ-ray observations have reached sufficient sensitivity to explore relevant velocity-averaged cross sections for DM annihilation into two γ-ray photons at the level expected from the thermal relic density for TeV DM particles.

Short-Term Prognostic Index for Breast Cancer: NPI or Lpi.

Axillary lymph node involvement is an important prognostic factor for breast cancer survival but is confounded by the number of nodes examined. We compare the performance of the log odds prognostic index (Lpi), using a ratio of the positive versus negative lymph nodes, with the Nottingham Prognostic Index (NPI) for short-term breast cancer specific disease free survival. A total of 1818 operable breast cancer patients treated in the University Hospital of Leuven between 2000 and 2005 were included. The performance of the NPI and Lpi were compared on two levels: calibration and discrimination. The latter was evaluated using the concordance index (cindex), the number of patients in the extreme groups, and difference in event rates between these. The NPI had a significant higher cindex, but a significant lower percentage of patients in the extreme risk groups. After updating both indices, no significant differences between NPI and Lpi were noted.

Cathepsin B, cathepsin H, cathepsin X and cystatin C in sera of patients with early-stage and inflammatory breast cancer.

Numerous studies have linked cathepsins and their inhibitor cystatin C to tumor invasion and metastasis. We examined whether cathepsin B, cathepsin H, cathepsin X and cystatin C could be detected in sera from women with early stage or inflammatory breast cancer and whether they correlated with clinicopathological characteristics. Preoperative serum was obtained from 176 patients with early-stage breast cancer (tumor size

Genetic polymorphisms of matrix metalloproteinases in lung, breast and colorectal cancer.

The matrix metalloproteinases (MMPs) can degrade various components of the extracellular matrix and are implicated in the development and progression of cancer. There is evidence suggesting an association of MMP gene polymorphisms with cancer susceptibility and/or metastasis. This paper reviews the findings on several single nucleotide polymorphisms in the collagenase, stromelysin and gelatinase genes in lung cancer, breast cancer and colorectal cancer.

Age interacts with the expression of steroid and HER-2 receptors in operable invasive breast cancer.

BACKGROUND: The negative association between the oestrogen receptor (ER) and the human epidermal growth factor receptor 2 (HER-2) in breast cancer travels in both directions. ER+ tumours are less likely HER-2+ and HER-2+ tumours are less likely ER+. METHODS: We studied the age-related immunohistochemical (IHC) expression of ER, progesterone receptor (PR) and HER-2 in 2,227 tumours using age as a continuous variable. Steroid receptors were considered positive for any nuclear staining of invasive cancer cells and for HER-2, either for strong expression by IHC (score 3+) or gene amplification by fluorescence in situ hybridisation (FISH). Based on nonparametric regression, the age-related association between steroid receptors and HER-2 was presented as likelihood curves. RESULTS: The association between ER or PR and HER-2 is age-related. The age-related expression of ER and PR is HER-2 dependent. In HER-2(-) cases, the odds ratio (OR) for being ER+ was 2.594 (95% CI = 1.874-3.591) up to age 50 and age-independent thereafter; for PR-expression the OR was 2.687 (95% CI = 1.780-4.057) up to age 45 and 0.847 (95% CI = 0.761-0.942) thereafter. In HER-2+ cases, the OR was 0.806 (95% CI = 0.656-0.991) to be ER+ and 0.722 (95% CI = 0.589-0.886) to be PR+. The age-related OR for breast cancers to be HER-2+ is steroid receptor dependent. Taking together, ER+PR+HER-2+ breast cancers appear on average 5.4 years earlier than breast cancers of any other ER/PR/HER-2 phenotype (95% CI = 3.3-7.5; P < 0.0001). CONCLUSION: There is a qualitative interaction between age and expression of steroid and HER-2 receptors. Our findings suggest a strong age-related selective growth advantage for breast tumour cells belonging to the ER+PR+HER-2+ subgroup.

Matrix metalloproteinase expression patterns in luminal A type breast carcinomas.

OBJECTIVE: Aberrant expression of individual matrix metalloproteinases has been associated with poor prognosis in various human carcinomas. The current study aimed at defining an RNA expression profile of various MMPs in breast cancer and correlating their expression with clinicopathological parameters. METHODS: The RNA expression patterns of 6 MMPs (MMP2, MMP8, MMP9, MMP10, MMP11, MMP13) were determined in 25 breast carcinomas using quantitative RT-PCR and correlated with clinicopathological parameters, including menopausal status, tumor size and grade, and lymph node involvement. RESULTS: We observed high MMP2 levels more frequently in premenopausal than in postmenopausal women (p=0.02). Analysis of luminal A type invasive ductal carcinomas (19/25), revealed an even stronger association of MMP2 with menopausal status (p=0.005). Within this subgroup, we also found a correlation between MMP11 and menopausal status (p=0.02). No correlation was found between MMP expressions and other clinicopathological parameters. In co-expression analyses MMP2-MMP10 and MMP8-MMP9 showed a weak correlation of their expression. CONCLUSIONS: Although this is a pilot study, our findings indicate that luminal A invasive ductal carcinomas commonly express high MMP2 and MMP11 levels in premenopausal breast cancer patients and suggest a co-regulation of MMP2-MMP10 and MMP8-MMP9.

Plasma gelatinase levels in patients with primary breast cancer in relation to axillary lymph node status, Her2/neu expression and other clinicopathological variables.

Matrix metalloproteinases (MMPs), in particular the gelatinases MMP2 and MMP9, are important mediators of tumour invasion and metastasis. We examined whether plasma gelatinase levels could predict lymph node metastasis in breast cancer patients. Further, we investigated the relationship of plasma gelatinase levels with Her2/neu expression, recently acknowledged as an important prognostic factor for recurrence, and with various clinicopathological factors. Preoperative plasma samples from 81 breast cancer patients were collected. Total and active gelatinase levels were measured by enzyme immunoassays and activity assays, respectively. Neither total nor active plasma MMP2 levels correlated with nodal status or with any of the classical clinicopathological factors including histological tumour type, tumour size and grade and hormone receptor status. Patients with Her2/neu overexpressing tumours showed an increase of 27% (P=0.007) in plasma MMP2 activity, but not in total MMP2, compared with patients without overexpression. MMP9 levels, total and active, did not correlate with any of the investigated variables. In contrast to MMP9, total MMP2 levels correlated significantly with active MMP2 levels. In summary, total and active plasma gelatinase levels failed to identify high risk for axillary lymph node metastasis. Active plasma MMP2 was significantly increased in patients with Her2/neu overexpressing tumours, suggesting a role for Her2/neu in the signalling pathways of MMP2 activation in carcinogenesis. However, this increase was too small to be of clinical use. Furthermore, no relationship was found between plasma gelatinase levels, total or active, and any of the clinicopathological prognostic factors.

Cardiac protein kinase C expression in two models of cardiac hypertrophy associated with an activated cardiac renin-angiotensin system: effects of experimental hyperthyroidism and genetic hypertension (the mRen-2 rat).

There is evidence for a role of protein kinase C (PKC) in the development of cardiac hypertrophy. We examined the expression of individual PKC isoforms in the adult rat heart in two distinct, well-characterised in vivo models of cardiac hypertrophy associated with an activated cardiac renin-angiotensin system, namely experimental hyperthyroidism and the TGR(mRen2)27 rat. The cardiac expression of a range of PKC isoforms (PKC-alpha, PKC-omega, PKC-epsilon, PKC-gamma, and PKC-tau) was examined by immuno-blotting. Our work demonstrates that the expression of total cardiac nPKC-omega and nPKC-epsilon relative to protein is selectively and differentially modified in these models. A consistent up-regulation of nPKC-omega in conjunction with overall down-regulation of nPKC-epsilon was observed in both models. The expression of other PKC isoforms was unaffected. The divergent responses of the expression of the two nPKC isoforms to an activated cardiac renin-angiotensin system in vivo in adulthood suggest that these individual nPKC isoforms subserve specific roles in the response.

Classical, novel and atypical isoforms of PKC stimulate ANF- and TRE/AP-1-regulated-promoter activity in ventricular cardiomyocytes.

Cultured neonatal rat ventricular myocytes were co-transfected with expression plasmids encoding protein kinase C (PKC) isoforms from each of the PKC subfamilies (classical PKC-alpha, novel PKC-epsilon or atypical PKC-zeta) together with an atrial natriuretic factor (ANF) reporter plasmid. Each PKC had been rendered constitutively active by a single Ala-->Glu mutation or a small deletion in the inhibitory pseudosubstrate site. cPKC-alpha, nPKC-epsilon or aPKC-zeta expression plasmids each stimulated ANF-promoter activity and expression of a reporter gene under the control of a 12-O-tetradecanoylphorbol 13-acetate-response element (TRE). Upregulation of the ANF promoter is characteristic of the hypertrophic response in the heart ventricle and a TRE is present in the ANF promoter. Thus all subfamilies of PKC may have the potential to contribute to hypertrophic response in cardiomyocytes.