The endocannabinoid system (ECS) has been placed in the anti-cancer spotlight in the last decade. The immense data load published on its dual role in both tumorigenesis and inhibition of tumor growth and metastatic spread has transformed the cannabinoid receptors CB1 (CB1R) and CB2 (CB2R), and other members of the endocannabinoid-like system, into attractive new targets for the treatment of various cancer subtypes. Although the clinical use of cannabinoids has been extensively documented in the palliative setting, clinical trials on their application as anti-cancer drugs are still ongoing. As drug repurposing is significantly faster and more economical than de novo introduction of a new drug into the clinic, there is hope that the existing pharmacokinetic and safety data on the ECS ligands will contribute to their successful translation into oncological healthcare. CB1R and CB2R are members of a large family of membrane proteins called G protein-coupled receptors (GPCR). GPCRs can form homodimers, heterodimers and higher order oligomers with other GPCRs or non-GPCRs. Currently, several CB1R and CB2R-containing heteromers have been reported and, in cancer cells, CB2R form heteromers with the G protein-coupled chemokine receptor CXCR4, the G protein-coupled receptor 55 (GPR55) and the tyrosine kinase receptor (TKR) human V-Erb-B2 Avian Erythroblastic Leukemia Viral Oncogene Homolog 2 (HER2). These protein complexes possess unique pharmacological and signaling properties, and their modulation might affect the antitumoral activity of the ECS. This review will explore the potential of the endocannabinoid network in the anti-cancer setting as well as the clinical and ethical pitfalls behind it, and will develop on the value of cannabinoid receptor heteromers as potential new targets for anti-cancer therapies and as prognostic biomarkers.

In line with the observed effects of food cysteine proteases in occupational allergy, these results suggest that disruption of tight junctions by food cysteine proteases may contribute to the process of sensitization in food allergy.

Screening with low-dose computed tomography of high-risk individuals with a smoking history reduces lung cancer mortality. Current screening guidelines and eligibility criteria can miss more than 50% of lung cancers, and in some geographic areas, such as East Asia, a large proportion

The various components of the endocannabinoid system (ECS), such as the cannabinoid receptors (CBRs), cannabinoid ligands, and the signalling network behind it, are implicated in several tumour-related states, both as favourable and unfavourable factors. This review analyses the ECS’s complex involvement in the susceptibility to cancer, prognosis, and response to treatment, focusing on its relationship with cancer biology in selected solid cancers (breast, gastrointestinal, gynaecological, prostate cancer, thoracic, thyroid, CNS tumours, and melanoma). Changes in the expression and activation of CBRs, as well as their ability to form distinct functional heteromers affect the cell’s tumourigenic potential and their signalling properties, leading to pharmacologically different outcomes. Thus, the same ECS component can exert both protective and pathogenic effects in different tumour subtypes, which are often pathologically driven by different biological factors. The use of endogenous and exogenous cannabinoids as anti-cancer agents, and the range of effects they might induce (cell death, regulation of angiogenesis, and invasion or anticancer immunity), depend in great deal on the tumour type and the specific ECS component that they target. Although an attractive target, the use of ECS components in anti-cancer treatment is still interlinked with many legal and ethical issues that need to be considered.

Nepeta rtanjensis Diklić & Milojević (fam. Lamiaceae) is an endemic, critically endangered plant, protectedby the law in Serbia. Various biological activities have been ascribed to its major constituents, nepeta-lactones. In this study we describe for the first time cytotoxic activity of N. rtanjensis essential oil (EO),obtained from field cultivated plants, which was found to be especially rich in trans,cis-nepetalactone.MTT assays indicated that after 72 h of treatment the EO exhibited cytotoxic activity on investigatedcancer cell lines: HeLa, K562, A549, LS-174 and MDA-MB-231. Normal cell line (MRC-5) was the leastsensitive to the treatment and IC50value for this cell line was not reached within the tested range ofEO concentrations (up to 0.1 L/mL). Analysis of morphological changes of treated cells confirmed thehigher sensitivity of tumor cells than normal cells to the tested EO. Application of N. rtanjensis EO resultedin the appearance of morphological changes in tested cancer cell lines characteristic for apoptotic celldeath, and induced perturbations of the cell cycle of HeLa cells. In addition, upregulation of Bax and p53,and downregulation of Bcl-2, and Skp2 genes, involved in apoptotic signalling cascades, confirmed anapoptosis-inducing effect of N. rtanjensis EO on HeLa cells. Presented results highlighted the potential ofN. rtanjensis EO in anticancer therapy.

BackgroundRadiation therapy is an indispensable part of various treatment modalities for breast cancer. Specifically, for non-inflammatory locally advanced breast cancer (LABC) patients, preoperative radiotherapy (pRT) is currently indicated as a second line therapy in the event of lack of response to neoadjuvant chemotherapy. Still approximately one third of patients fails to respond favourably to pRT. The aim of this study was to explore molecular mechanisms underlying differential response to radiotherapy (RT) to identify predictive biomarkers and potential targets for increasing radiosensitivity.MethodsThe study was based on a cohort of 134 LABC patients, treated at the Institute of Oncology and Radiology of Serbia (IORS) with pRT, without previous or concomitant systemic therapy. Baseline transcriptional profiles were established using Agilent 60 K microarray platform in a subset of 23 formalin-fixed paraffin-embedded (FFPE) LABC tumour samples of which 11 radiotherapy naïve and 3 post-radiotherapy samples passed quality control and were used for downstream analysis. Biological networks and signalling pathways underlying differential response to RT were identified using Ingenuity Pathways Analysis software. Predictive value of candidate genes in the preoperative setting was further validated by qRT-PCR in an independent subset of 60 LABC samples of which 42 had sufficient quality for data analysis, and in postoperative setting using microarray data from 344 node-negative breast cancer patients (Erasmus cohort, GSE2034 and GSE5327) treated either with surgery only (20%) or surgery with RT (80%).ResultsWe identified 192 significantly differentially expressed genes (FDR < 0.10) between pRT-responsive and non-responsive tumours, related to regulation of cellular development, growth and proliferation, cell cycle control of chromosomal replication, glucose metabolism and NAD biosynthesis II route. APOA1, MAP3K4, and MMP14 genes were differentially expressed (FDR < 0.20) between pRT responders and non-responders in preoperative setting, while MAP3K4 was further validated as RT-specific predictive biomarker of distant metastasis free survival (HR = 2.54, [95%CI:1.42–4.55], p = 0.002) in the postoperative setting.ConclusionsThis study pinpoints MAP3K4 as a putative biomarker of response to RT in both preoperative and postoperative settings and a potential target for radiosensitising combination therapy, warranting further pre-clinical studies and prospective clinical validation.Electronic supplementary materialThe online version of this article (10.1186/s13014-018-1129-4) contains supplementary material, which is available to authorized users.

Breast cancer is a complex disease with both genetic and environmental factors involved in its etiology. An important role of polymorphisms in genes involved in DNA repair has been reported related to breast cancer risk. We conducted a case-control study in order to investigate the association of RAD51 135G>C and TP53 Arg72Pro polymorphisms with breast cancer in Serbian women.48 BRCA negative women with breast cancer and family history of breast/ovarian cancer (hereditary group), 107 women with breast cancer but without family history of the disease (sporadic group) and 114 healthy women without a history of the disease (control group) were included. Restriction fragment length polymorphism was used for genotyping. Genotype and allelic frequencies, the odds ratio (OR) and the 95 % confidence interval (CI) were calculated as an estimate of relative risk. The Hardy-Weinberg equilibrium was tested using χ(2) test. Significance was considered for p < 0.05. RAD51 135G>C showed statistically significant association of CC genotype and increased breast cancer risk (OR 10.28, 95 % CI 1.12-94.5) in hereditary group of patients compared to the control group. Regarding the TP53 Arg72Pro, we showed statistical significance for ProPro + ProArg comparing to ArgArg (OR 2.34, 95 %, CI 1.17-4.70) in hereditary compared to sporadic group. RAD51 135G>C contributes to hereditary breast cancer in Serbian population, with CC genotype as a risk factor. We also found that carriers of Pro allele of TP53 codon 72 is related to hereditary cancer comparing to sporadic one, which indicates it as a potential risk factor for hereditary form of disease.

Toxicity of conventional chemotherapeutics highlights the requirement for complementary or alternative medicines that would reduce side effects and improve their anticancer effectiveness. European mistletoe (Viscum album) has long been used as a complementary and alternative medicine supporting cancer therapy. The aim of this study was to investigate synergistic antitumor action of V. album extract and doxorubicin during co-treatment of chemoresistant chronic myelogenic leukemia K562 cells. Combined treatment of leukemia cells led to inhibitory synergism at sub-apoptotic doxorubicin concentrations and multifold reduction of cytotoxic effects in healthy control cells. Prolonged co-treatment was associated with reduced G2/M accumulation and increased expression of early and late apoptotic markers. Our data indicate that V. album extract increases antileukemic effectiveness of doxorubicin against resistant K562 cells by preventing G2/M arrest and inducing apoptosis.