The secretory small GTPase Rab27B as a marker for breast cancer progression.

In contemporary oncology practice, an urgent need remains to refine the prognostic assessment of breast cancer. It is still difficult to identify patients with early breast cancer who are likely to benefit from adjuvant chemotherapy. Although invasion of cancer cells is the main prognostic denominator in tumor malignancy, our molecular understanding and diagnosis are often inadequate to cope with this activity. Therefore, deciphering molecular pathways of how tumors invade and metastasize may help in the identification of a useful prognostic marker. We recently discovered that the secretory small GTPase Rab27B, a regulator of vesicle exocytosis, delivers proinvasive signals for increased invasiveness, tumor size, and metastasis of various estrogen receptor (ER)-positive breast cancer cell lines, both in vitro and in vivo. In human breast cancer specimens, the presence of Rab27B protein proved to be associated with a low degree of differentiation and the presence of lymph node metastasis in ER-positive breast cancer.publishersversionpublishe

LEARNING AQUAPONICS POST COVID-19 THROUGH START-UP INDUSTRY PARTNERSHIPS

PROBLEM Pre-COVID-19 lockdowns (2019), we usually organise for our students to visit a commercial aquaponics facility, Green Camel1, which is a start-up company located within The University of Sydney’s Cobbitty campus. Green Camel produces both barramundi (fish) and pesticide-free organic vegetables, such as tomatoes and basil. Effluent from the barramundi is passed through a bioreactor which converts ammonium to nitrate, which is then utilised by the vegetables in a closed-loop system. During the COVID-19 pandemic (2020-21), we had to live-stream and video field visits to remotely located students and international students who are unable to travel to Australia to experience the field visits. We were not very happy with video recording field practicals, since the students did not get a hands-on experience with aquaponics. PLAN After the lifting of the COVID-19 restrictions, the first author partnered with start-up company, Farmwall2, in its STEM Pilot Program. In this Program, Farmwall provided students with an aquaponic ecosystem classroom kit including a fish tank, plant trays, plants, seeds, gravel and micro-organisms for converting ammonium to nitrate, as well as a separate hydroponics kit. An online education platform was also provided with detailed instructions for setting up the aquaponics kit, as well as step by step video instructions on how to maintain the fish tank and grow the vegetables including microgreens. Teachers and students were able to engage with the step-by-step process of setting up the aquaponics system as well as monitoring the health of the system (e.g., pH, ammonium, nitrate and nitrite levels). ACTION Farmwall provided the students with an aquaponic classroom kit so that they can engage in setting up and maintaining a model aquaponics unit. One of the students also contributed biological filtration, white cloud mountain minnows (Tanichthys micagemmae; fish) and aquatic plants. During the lab practicals, students harvested and tasted the snow pea microgreens grown using the aquaponic classroom unit. Some students were also inspired to convert their home fish tanks into home mini-aquaponic systems. REFLECTION In addition to visiting or watching videos of field visits, students learnt to set up and maintain an aquaponics unit to produce vegetables such as microgreens, which is a life skill that they can use in the post-COVID-19 world. Live-streamed and in person practicals provided useful information on how students could set up and produce vegetables including microgreens, becoming potentially self-sufficient. In addition to learning the theory of aquaponic production, students gained the life skills of a close-loop system to produce their own organic vegetables at home. 1https://greencamel.com.au/ 2https://farmwall.com

The secretory small GTPase Rab27B as a marker for breast cancer progression

In contemporary oncology practice, an urgent need remains to refine the prognostic assessment of breast cancer. It is still difficult to identify patients with early breast cancer who are likely to benefit from adjuvant chemotherapy. Although invasion of cancer cells is the main prognostic denominator in tumor malignancy, our molecular understanding and diagnosis are often inadequate to cope with this activity. Therefore, deciphering molecular pathways of how tumors invade and metastasize may help in the identification of a useful prognostic marker. We recently discovered that the secretory small GTPase Rab27B, a regulator of vesicle exocytosis, delivers proinvasive signals for increased invasiveness, tumor size, and metastasis of various estrogen receptor (ER)-positive breast cancer cell lines, both in vitro and in vivo. In human breast cancer specimens, the presence of Rab27B protein proved to be associated with a low degree of differentiation and the presence of lymph node metastasis in ER-positive breast cancer

Adipose tissue in breast cancer : not an idle bystander but an active participant in breast cancer progression

Background: Adipose tissue is a dynamic organ that secretes a plethora of molecules called adipokines. In breast cancer we find a unique situation were genetically changed cells (the cancer cells) are in close contact with adipocytes. Moreover, obesity is a known negative prognostic marker for postmenopausal breast cancer patients. We hypothesize that adipocyte-derived factors influence breast cancer progression. Materials and methods: Adipose tissue was collected from breast cancer patients undergoing a mastectomy. After macroscopic removal of blood vessels and connective tissue, the adipose tissue was carefully cut into 2-3mm3 pieces and were incubated in specific adipose-tissue culture medium. After 24h, the medium was collected and the quality was checked by determining the concentration of total proteins, leptin, adiponectin, TNFalpha and triglycerides. This conditioned medium of adipose tissue (CM AT) was used for in vitro experimentation with MCF-7 breast cancer cells. Results: Effect of AT on morphology and aggregation: when MCF-7 cells are grown in a culture flask, they tend to form round compact islands. Under influence of CM AT, the islands form sharp edges, the cells in an island can be counted individually and they show scattering. Importantly, despite the major changes in cellular morphology, CM AT removal rescued the compact island formation of MCF-7 cells. In the slow aggregation assay, cells treated with CM AT (and a subtherapeutic concentration of a neutralizing E-cadherin antibody) lost the ability to form compact aggregates. Furthermore, MCF-7 spheroids placed inside adipose tissue showed massive reorganization into an irregularly shaped mass. Effect of AT on proliferation: starting from an equal number of cells and counting them every 2 days, it became clear that MCF-7 cells with CM AT had a higher rate of proliferation than MCF-7 cells in control medium. This stimulation of proliferation was confirmed by cell cycle analysis which revealed a doubling of cells in the G2/M phase, and western blot which showed an upregulation of cyclin A and cyclin E, both positive regulators of the cell cycle. Effect of AT on invasion: a 24h collagen type I invasion assay revealed invasive characteristics of MCF-7 cells treated with CM AT while MCF-7 cells in control conditions are round and non-invasive. In contrast, a transwell collagen test over 14 days was not able to show MCF-7 cells invading the collagen gel under influence of CM AT. However, the growth pattern of MCF-7 cells on the collagen gel was clearly disorganised when compared with the control situation. Conclusion: These findings suggest that adipose tissue-derived factors exert a dramatic selective force on patterning, invasion and growth of MCF-7 breast cancer cells. Unraveling the mechanism behind these observations may provide vital information regarding the link between obesity and poor prognosis in postmenopausal breast cancer

Secretome analysis of breast cancer-associated adipose tissue to identify paracrine regulators of breast cancer growth

Adipose tissue secretes a plethora of adipokines as evidenced by characterization of subcutaneous and visceral adipose tissue secretomes. However, adipose tissue composition and secretion pattern is depot and disease dependent, influencing the adipose tissue secretome. We investigated the secretome of cancer-associated adipose tissue (CAAT) explants from breast cancer patients and explored its role in breast cancer proliferation. CAAT proteins were identified by LC-MS/MS and human protein antibody arrays and stimulated proliferation of three breast cancer cell lines. Kinomics and transcriptomics of MCF-7 breast cancer cells treated with the secretome of CAAT revealed activation of Akt-, ERK- and JNK-pathways and differential expression of activator protein 1 (AP-1) and cAMP responsive element-binding protein (CREB) target genes. The cyclin-dependent kinase (CDK) 4/6-inhibitor palbociclib significantly abrogated CAAT-enhanced breast cancer cell proliferation. Our work characterizes the specific breast CAAT protein secretome and reveals its pro-proliferative potency in breast cancer

Feasibility study on pre or postoperative accelerated radiotherapy (POP-ART) in breast cancer patients

Background: In early-stage breast cancer, the cornerstone of treatment is surgery. After breast-conserving surgery, adjuvant radiotherapy has shown to improve locoregional control and overall survival rates. The use of breast radiotherapy in the preoperative (preop) setting is far less common. Nevertheless, it might improve disease-free survival as compared to postoperative radiotherapy. There is also a possibility of downsizing the tumour which might lead to a lower need for mastectomy. There are some obstacles that complicate its introduction into daily practice. It may complicate surgery or lead to an increase in wound complications or delayed wound healing. Another fear of preop radiotherapy is delaying surgery for too long. At Ghent University Hospital, we have experience with a 5-fraction radiotherapy schedule allowing radiotherapy delivery in a very short time span. Methods: Twenty female breast cancer patients with non-metastatic disease receiving preop chemotherapy will be randomized between preop or postoperative radiotherapy. The feasibility of preop radiotherapy will be evaluated based on overall treatment time. All patients will be treated in 5 fractions of 5.7 Gy to the whole breast with a simultaneous integrated boost to the tumour/tumour bed of 5 × 6.2 Gy. In case of lymph node irradiation, the lymph node regions will receive a dose of 27 Gy in 5 fractions of 5.4 Gy. The total duration of therapy will be 10 to 12 days. In the preop group, overall treatment time is defined as the time between diagnosis and the day of last surgery, in the postop group between diagnosis and last irradiation fraction. Toxicity related to surgery, radio-, and chemotherapy will be evaluated on dedicated case-report forms at predefined time points. Tumour response will be evaluated on the pathology report and on MRI at baseline and in the interval between chemotherapy and surgery. Discussion: The primary objective of the trial is to investigate the feasibility of preop radiotherapy. Secondary objectives are to search for biomarkers of response and toxicity and identify the involved cell death mechanisms and the effect of preop breast radiotherapy on the in-situ immune micro-environment

Molecular and pathological signatures of epithelial–mesenchymal transitions at the cancer invasion front

Reduction of epithelial cell–cell adhesion via the transcriptional repression of cadherins in combination with the acquisition of mesenchymal properties are key determinants of epithelial–mesenchymal transition (EMT). EMT is associated with early stages of carcinogenesis, cancer invasion and recurrence. Furthermore, the tumor stroma dictates EMT through intensive bidirectional communication. The pathological analysis of EMT signatures is critically, especially to determine the presence of cancer cells at the resection margins of a tumor. When diffusion barriers disappear, EMT markers may be detected in sera from cancer patients. The detection of EMT signatures is not only important for diagnosis but can also be exploited to enhance classical chemotherapy treatments. In conclusion, further detailed understanding of the contextual cues and molecular mediators that control EMT will be required in order to develop diagnostic tools and small molecule inhibitors with potential clinical implications

Effect of brine salting and drying temperature on nutritive value of tambaqui fish (Colossoma macropomum)

Effect of brine salting and drying temperature on nutritive value of tambaqui fish (Colossoma macropomum) Awot Teklu Mebratu1,2, Yohannes Tekle Asfaw2, Wouter Merckx3, Wouter H. Hendriks4, and Geert Paul Jules Janssens1 1Department of Nutrition, Genetics and Ethology, Faculty of Veterinary Medicine, Ghent University, Heidestraat 19, 9820 Merelbeke, Belgium; 2Department of Animal Reproduction and Welfare, College of Veterinary Sciences, Mekelle University, PO BOX 2081, Mekelle, Ethiopia; 3TransFarm, Catholic University of Leuven, Leuven, Belgium; 4Animal Nutrition Group, Wageningen University, P.O. Box 338, 6700 AH Wageningen, The Netherlands. e-mail: [email protected] Introduction. The combination effect of brining and oven-drying as food conservation tools [1] on the nutritive value of tambaqui fish was tested, including lysine reactivity to evaluate the extent of Maillard reactions. The effect of brine salting (15% w/w) prior to oven-drying at different temperatures (30, 35, 40, 45, 50, 55, and 60°C) on the nutrient profile of tambaqui (Colossoma macropomum) was evaluated in the current study. Animals, material and methods. Whole fish samples (n=48) were collected from TRANSfarm, Lovenjoel, Belgium, and used in the study. Uniformly sliced whole fish samples were grouped into two as brine-salted and non-salted and run at seven different oven-drying temperatures, 30, 35, 40, 45, 50, 55, and 60°C for a period of 23 h each. Freeze-dried samples were then used for proximate (DM, CP, CF, & ash), mineral (Ca, Na, K, Cu, Fe, Mg, Mn, Br, P, & Zn) and amino acid analyses [2,3]. Univariate one-way ANOVA & PCA were the statistical tools used with p<0.05 set as cut-off point for significance. Results and discussion. Results showed that drying temperature had no (P>0.05) effect on the nutrient profiles of the fish whereas brining reduced the overall protein concentration and specific amino acids: the osmolyte Tau (56%) followed by Met (17%), Cys (11%) and His (10%). The decrease in Lys by 7% could have caused a significant (P<0.005) decrease in available-lysine by 11%. Likewise, the microminerals Se and I, and the macrominerals K and Mg were reduced by brining with 14, 38, 42, and 18% percent losses, respectively. Brining resulted in an obvious enormous increase (744%) in Na concentration. Results of multivariate analysis showed a negative association between brining (“saltcode”), Na, and ash on one side of the component and most other nutrients on the other. However, there were no (Ala and Arg) and positive (Gly and Pro) associations with these amino acids that are prominent in connective tissue (skin, scales, skeleton). Likewise, the non-significant effect of salt on Zn, Fe, fat, and available Lys are typically depicted by their closer tie to the vertical line. The lack of effect of temperature (“temp”) can be seen by its presence in the centre. Figure 1. Multivariate classification of nutrient profiles, brining and temperature. Conclusion. Drying without brining may therefore be a better option, although this must be considered in combination with the goal of pathogen reduction. References: [1] Gallart-Jornet et al. (2007) J. Food Eng. 79: 261-70; [2] AOAC (1990); [3] AOAC (1995)

Histologic tumor type as a determinant of survival in hormone receptor-positive, HER2-negative, pT1-3 invasive ductal and lobular breast cancer

PurposeThe aim of the study was to compare the difference in survival between invasive ductal (IDC) and lobular carcinoma (ILC).MethodsData of patients (n = 1843) with a hormone receptor-positive, HER2-negative, pT1-3 IDC or ILC cancer without distant metastasis, treated at the Ghent University Hospital over the time period 2001-2015, were analyzed.ResultsILC represented 13.9% of the tumors, had a higher percentage of pT3 and pN3 stages than IDC, lymphovascular space invasion (LVSI) was less present and Ki-67 was mostly low. 73.9% of ILCs were grade 2, whereas IDC had more grade 1 and grade 3 tumors. Kaplan-Meier curves and log-rank testing showed a significant worse DFS for ILC with pN >= 1 than for their IDC counterpart. In a multivariable Cox regression analysis the histologic tumor type, ductal or lobular, was a determinant of DFS over 120 months (IDC as reference; hazard ratio for ILC 1.77, 95% CI 1.08-2.90) just as the ER Allred score (hazard ratio 0.84, 95% CI 0.78-0.91), LVSI (hazard ratio 1.75, 95% CI 1.12-2.74) and pN3 (hazard ratio 2.29, 95% CI 1.03-5.09). Determinants of OS over ten years were age (hazard ratio 1.05, 95% CI 1.02-1.07), LVSI (hazard ratio 3.62, 95% CI 1.92-6.82) and the ER Allred score (hazard ratio 0.80, 95% CI 0.73-0.89).ConclusionThe histologic tumor type, ductal or lobular, determines DFS in hormone receptor-positive, HER2-negative, pT1-3 breast cancer besides the ER Allred score, LVSI and pN3