Ispitivanje fermentacijskih svojstava smeđe riže i rižinih mekinja radi uzgoja Lactobacillus plantarum NCIMB 8826

The growth on rice-based media of the probiotic strain Lactobacillus plantarum NCIMB 8826 isolated from the human gut has been investigated. Fermentation broths were obtained from the whole grain brown rice and rice bran of two Thai rice cultivars, RD6 (glutinous) and RD17 (nonglutinous). The rice used was not germinated and fermentations were carried out in a single step without growth supplementation. L. plantarum grew well in all tested broths, and a final biomass value of approx. 10.4 log CFU/mL was obtained. In addition, biomass production and substrate depletion were satisfactorily modelled using an unstructured mathematical model. There were no statistical differences observed among the four rice media. The results confirm that brown rice and rice bran are suitable substrates for the culture of the probiotic L. plantarum NCIMB 8826. Rice bran, currently a by-product of the traditional cereal processing industry, has shown similar fermentability to brown rice. This indicates that rice bran or rice bran extracts could be used in new probiotic food developments, while probably still maintaining other functional properties of the bran.U radu je ispitan rast soja mliječno-kiselih probiotičkih bakterija Lactobacillus plantarum NCIMB 8826, izoliranog iz crijeva čovjeka, u podlogama s rižom. Pripremljene su podloge od integralne (smeđe) riže i mekinja dvaju kultivara tajlandske riže, RD6 i RD17. Upotrijebljena je nenaklijala riža, a fermentacija je provedena u jednom koraku i bez dodatka stimulatora rasta. Soj L. plantarum rastao je dobro u svim podlogama, pa je postignut maksimalni prinos biomase od 10,4 log CFU/mL. Proizvodnja biomase i potrošnja supstrata uspješno su modelirane pomoću nestrukturiranoga matematičkog modela. Nije uočena statistički bitna razlika između rezultata dobivenih uzgojem soja u četiri različite podloge. Rezultati potvrđuju da su tajlandska integralna riža i rižine mekinje prikladne podloge za uzgoj probiotičkoga soja Lactobacillus plantarum NCIMB 8826. Utvrđeno je da rižine mekinje, nusproizvod dobivanja ljuštene (bijele) riže, imaju slična fermentacijska svojstva kao i smeđa riža. Stoga je zaključeno da se rižine mekinje ili ekstrakt rižinih mekinja mogu uspješno upotrijebiti za dobivanje novih probiotičkih proizvoda, a da pritom ne izgube ostala funkcionalna svojstva

In vivo murine model of acquired resistance in myeloma reveals differential mechanisms for lenalidomide and pomalidomide in combination with dexamethasone

The development of resistance to therapy is unavoidable in the history of multiple myeloma patients. Therefore, the study of its characteristics and mechanisms is critical in the search for novel therapeutic approaches to overcome it. This effort is hampered by the absence of appropriate preclinical models, especially those mimicking acquired resistance. Here we present an in vivo model of acquired resistance based on the continuous treatment of mice bearing subcutaneous MM1S plasmacytomas. Xenografts acquired resistance to two generations of immunomodulatory drugs (IMiDs; lenalidomide and pomalidomide) in combination with dexamethasone, that was reversible after a wash-out period. Furthermore, lenalidomide-dexamethasone (LD) or pomalidomide-dexamethasone (PD) did not display cross-resistance, which could be due to the differential requirements of the key target Cereblon and its substrates Aiolos and Ikaros observed in cells resistant to each combination. Differential gene expression profiles of LD and PD could also explain the absence of cross-resistance. Onset of resistance to both combinations was accompanied by upregulation of the mitogen-activated protein kinaseextracellular signal-regulated kinase (ERK) kinase (MEK)ERK pathway and addition of selumetinib, a small-molecule MEK inhibitor, could resensitize resistant cells. Our results provide insights into the mechanisms of acquired resistance to LD and PD combinations and offer possible therapeutic approaches to addressing IMiD resistance in the clinic.Peer Reviewe

Preclinical and clinical characterization of fibroblast-derived neuregulin-1 on trastuzumab and pertuzumab activity in HER2-positive breast cancer

[Purpose]: To characterize expression of neuregulin-1 (NRG1), an HER3 ligand, in HER2-positive breast cancer and its relation with the efficacy of trastuzumab with or without pertuzumab.[Experimental Design]: Characterization of NRG1 expression in tumor cell lines, in tumor specimens, and in cancer-associated fibroblasts (CAFs). Patient-derived CAFs were used to investigate NRG1 impact on the activity of trastuzumab with or without pertuzumab in HER2-positive breast cancer cells. The relationship between NRG1 expression and pathologic response to anti-HER2–based neoadjuvant therapy was assessed in a retrospective patient cohort and in the NeoSphere trial.[Results]: NRG1 was expressed in HER2-positive breast cancer–derived fibroblasts at significantly higher levels than in cancer cells. NRG1 and the conditioned media (CM) from CAFs phosphorylated HER3 and AKT in cancer cells and mediated trastuzumab resistance. Stable genetic depletion of NRG1 from CAFs overcame trastuzumab resistance. Pertuzumab effectively suppressed trastuzumab resistance mediated by either NRG1 or CAF's CM. NRG1 engaged an epithelial-to-mesenchymal transition that was prevented by trastuzumab and pertuzumab. In clinical samples, stromal and/or tumor cell expression of NRG1 determined by immunohistochemistry was uncommon (13.2%) yet significantly linked with residual disease following trastuzumab-based neoadjuvant therapy. In the NeoSphere trial, the magnitude of the difference of pathologic complete response rates favoring the pertuzumab arm was higher in the NRG1-high group.[Conclusions]: CAF-derived NRG1 mediates trastuzumab resistance through HER3/AKT, which might be reverted by pertuzumab. In patients with HER2-positive breast cancer, high expression of NRG1 was associated to poor response to trastuzumab, but not in combination with pertuzumab.This work is supported by ISCIII (CIBERONC CB16/12/00481, CB16/12/00241, PI18/00382, PI18/00006, PI18/01219 and by Generalitat de Catalunya (2017 SGR 507). S. Menendez is supported by Department de Salut, Generalitat de Catalunya (PERIS SLT006/17/00040). MARBiobanc is supported by ISCiii/FEDER (PT17/0015/0011) and by “Xarxa de Bancs de tumors” sponsored by Pla Director d’ Oncologia de Catalunya (XBTC) and Fundacion Jimenez Díaz Biobanks Platform by PT13/0010/0012 grant. Ministry of Economy and Competitiveness of Spain (BFU2015-71371-R) and the CRIS Cancer Foundation provides support to A. Pandiella. Work carried out in our laboratories receive support from the European Community through the Regional Development Funding Program (FEDER). J.C. Montero is funded by the ISCIII through a Miguel Servet program (CPII17/00015) and receives research support from the same institution (PI18/00796). J. Albanell is supported by Breast Cancer Research Foundation (BCRF20-08), Instituto de Salud Carlos III Project Reference number AC15/00062 and the EC under the framework of the ERA-NET TRANSCAN-2 initiative co-financed by FEDER, Instituto de Salud Carlos III (CB16/12/00449 and PI19/01181), and Asociacion Espanola Contra el Cáncer (AECC)

ODZ1 allows glioblastoma to sustain invasiveness through a Myc-dependent transcriptional upregulation of RhoA

Long-term survival remains low for most patients with glioblastoma (GBM), which reveals the need for markers of disease outcome and novel therapeutic targets. We describe that ODZ1 (also known as TENM1), a type II transmembrane protein involved in fetal brain development, plays a crucial role in the invasion of GBM cells. Differentiation of glioblastoma stem-like cells drives the nuclear translocation of an intracellular fragment of ODZ1 through proteolytic cleavage by signal peptide peptidase-like 2a. The intracellular fragment of ODZ1 promotes cytoskeletal remodelling of GBM cells and invasion of the surrounding environment both in vitro and in vivo. Absence of ODZ1 by gene deletion or downregulation of ODZ1 by small interfering RNAs drastically reduces the invasive capacity of GBM cells. This activity is mediated by an ODZ1-triggered transcriptional pathway, through the E-box binding Myc protein, that promotes the expression and activation of Ras homolog family member A (RhoA) and subsequent activation of Rho-associated, coiled-coil containing protein kinase (ROCK). Overexpression of ODZ1 in GBM cells reduced survival of xenografted mice. Consistently, analysis of 122 GBM tumour samples revealed that the number of ODZ1-positive cells inversely correlated with overall and progression-free survival. Our findings establish a novel marker of invading GBM cells and consequently a potential marker of disease progression and a therapeutic target in GBM