Transcriptome analysis of newly established carboplatin-resistant ovarian cancer cell model reveals genes shared by drug resistance and drug-induced EMT.

BACKGROUND: In ovarian cancer (OC) therapy, even initially responsive patients develop drug resistance. METHODS: Here, we present an OC cell model composed of variants with differing degrees of acquired resistance to carboplatin (CBP), cross-resistance to paclitaxel, and CBP-induced metastatic properties (migration and invasion). Transcriptome data were analysed by two approaches identifying differentially expressed genes and CBP sensitivity-correlating genes. The impact of selected genes and signalling pathways on drug resistance and metastatic potential, along with their clinical relevance, was examined by in vitro and in silico approaches. RESULTS: TMEM200A and PRKAR1B were recognised as potentially involved in both phenomena, also having high predictive and prognostic values for OC patients. CBP-resistant MES-OV CBP8 cells were more sensitive to PI3K/Akt/mTOR pathway inhibitors Rapamycin, Wortmannin, SB216763, and transcription inhibitor Triptolide compared with parental MES-OV cells. When combined with CBP, Rapamycin decreased the sensitivity of parental cells while Triptolide sensitised drug-resistant cells to CBP. Four PI3K/Akt/mTOR inhibitors reduced migration in both cell lines. CONCLUSIONS: A newly established research model and two distinct transcriptome analysis approaches identified novel candidate genes enrolled in CBP resistance development and/or CBP-induced EMT and implied that one-gene targeting could be a better approach than signalling pathway inhibition for influencing both phenomena.

GT microsatellite repeats in the heme oxygenase-1 gene promoter associated with abdominal aortic aneurysm in Croatian patients.

Abdominal aortic aneurysm (AAA) is a complex genetic disorder caused by the interplay of genetic and environmental risk factors. The number of (GT)(n) repeats in the heme oxygenase-1 (HO-1) gene promoter modulates transcription of this enzyme, which might have anti-inflammatory, antioxidant, antiapoptotic, and antiproliferative effect. The distribution of alleles and genotypes in Croatian individuals genotyped for the (GT)(n) HO-1 polymorphism was similar to that in other European populations. Frequency of the short (S) alleles (GT < 25) was higher in AAA patients (41.9%) than in non-AAA individuals (28.2%, p = 0.0026) because there were more SL heterozygotes among the AAA patients. The SL genotype appeared to increase the risk for AAA, but the increase was not statistically significant after adjustment for age, sex, smoking, hypertension, and hyperlipidemia (OR = 1.53, 95% CI 0.90-3.09, p = 0.062). These findings contradict those of the only other study performed so far on the association of (GT)(n) HO-1 polymorphism and AAA.

Association of 1166A>C AT1R, -1562C>T MMP-9, ACE I/D, and CCR5Δ32 Polymorphisms with Abdominal Aortic Aneurysm in Croatian Patients.

AIM: The purpose of this case-control study was to assess the association of abdominal aortic aneurysm (AAA) in Croatian patients with four genetic polymorphisms: SNP 1166A>C in the angiotensin II type 1 receptor gene (AT1R); SNP -1562C>T in the matrix metalloproteinase-9 gene (MMP-9); the deletion of 32 bp in the chemokine receptor 5 gene (CCR5); and the insertion/deletion (I/D) of 287 bp in the angiotensin-converting enzyme gene (ACE). METHODS: Case-control study conducted with 117 patients with confirmed AAA (AAA+) and 117 control subjects (AAA-). Genotyping was performed using PCR or PCR-RFLP analysis. Statistical analyses were performed using MedCalc 12.1 software. RESULTS: The deletion of 287 bp in the ACE gene (allele D) was more frequently found among AAA+ patients than AAA- subjects (66.7% vs. 47.9%, p = 0.0001), due principally to a higher percentage of DD homozygotes (46.2% vs. 15.4%, p < 0.0001). The associated increased risk for AAA was detected in both the nonadjusted recessive model of inheritance (odds ratio [OR] = 3.00, 95% confidence interval [CI] = 1.88-4.79, p = < 0.0001) and when adjusted for age, sex, smoking, hypertension, and hyperlipidemia (OR = 4.96; 95% CI = 1.68-14.59, p = 0.004). The adjusted recessive models also showed increased risk for AAA for the carriers of MMP-9 T allele (OR = 15.69, 95% CI = 1.40-175.41, p = 0.025). Patients with small aneurysms compared with those with large ones were more frequent carriers of the AT1R allele C (37.8% vs. 23.2%, p = 0.029), and logistic regression analysis showed decreased risk for developing large aneurysms in both adjusted models, dominant and recessive (OR = 0.3929, 95% CI = 0.1554-0.9932, p = 0.0483 and OR = 0.1728, 95% CI = 0.0331-0.9023; p = 0.0374, respectively). No difference among any type of the studied groups or subgroups was observed regarding the CCR5Δ32 polymorphism. CONCLUSIONS: ACE I/D is associated with AAA, and 1166A>C AT1R with the size of the aneurysm, while -1562C>T MMP-9 and CCR5Δ32 polymorphisms are most probably not associated with AAA in Croatian patients.

Identification of the multidrug resistance-associated protein (mrp) related gene in red mullet (Mullus barbatus).

Multixenobiotic resistance mechanism (MXR) in aquatic organisms is mediated by the activity of the P-glycoprotein (Pgp) transporter that binds and actively effluxes different chemicals out of cell. In addition to the Pgp, several other, non-Pgp transport proteins have been recently identified in different human and animal tissues. Given their characteristics and tissue distribution we hypothesized that members of the so-called multidrug resistance-associated protein (MRP) family may be expressed in aquatic organisms. This study attempted to identify MRP related genes in different tissues of several marine and freshwater bivalves (Mytilus galloprovincialis, Dreissena polymorpha, Anodonta cygnea) and fish species (Mullus barbatus, Cyprinus carpio, Salmo trutta). Following an alignment of known MRP1 and MRP2 human sequences, as well as the GenBank available mrp2 sequences from different animals, we determined highly conserved regions and used them to design three pairs of consensus primers. Total RNA was isolated, reverse transcribed to cDNA and the obtained cDNAs were PCR amplified with the corresponding primers. The amplified PCR products were sequenced and their homology compared with Pgp and MRP protein sequences from different species. The expression of MRP related mRNA was clearly identified only in liver tissue isolated from red mullet, with homologies at the protein level ranging from 75% to 76%. Described results clearly pointed at the possibility that at least in the red mullet MXR as a general defense mechanism may be mediated by the activities of at least two different types of transport proteins.

Azithromycin drives in vitro GM-CSF/IL-4-induced differentiation of human blood monocytes toward dendritic-like cells with regulatory properties.

Azithromycin, a macrolide antibacterial, has been shown to modify the phenotype of macrophages. We have investigated whether azithromycin in vitro is able to modulate the differentiation of human blood monocytes to DCs. iA-DCs appear to have a unique phenotype, characterized by increased granularity, adherence, and a surface molecule expression profile similar to that of MDCs, namely, CD1a⁻CD14⁻CD71⁺CD209(high), as well as high CD86 and HLA-DR expression. The iA-DC phenotype is associated with increased IL-6 and IL-10 release, increased CCL2 and CCL18 expression and release, and M-CSF expression, as well as reduced CCL17 expression and release. Upon maturation with LPS, A-DCs and MDCs exhibit decreased expression of HLA-DR and costimulatory molecules, CD40 and CD83, as well as an increase in IL-10 and a decrease in CCL17 and CXCL11 secretion. These modulated responses of iA-DCs were associated with the ability to reduce a MLR, together with enhanced phagocytic and efferocytotic properties. Azithromycin, added 2 h before activation of iDCs with LPS, enhanced IL-10 release and inhibited IL-6, IL-12p40, CXCL10, CXCL11, and CCL22 release. In conclusion, azithromycin modulates the differentiation of blood monocyte-derived DCs to form iA-DCs with a distinct phenotype similar to that of iMDCs, accompanied by enhanced phagocytic and efferocytic capabilities. It also modifies LPS-induced DC maturation by decreasing surface molecule expression required for T cell activation, increasing IL-10 production, and inducing MLR-reducing properties.