Purpose Dysregulation of miRNA profile has been associated with a broad spectrum of cellular processes underlying progression of various human malignancies. Increasing evidence suggests that specific microRNA clusters might be of clinical utility, especially in triple-negative breast carcinoma (TNBC), devoid of both predictive markers and potential therapeutic targets. Here we provide a comprehensive review of the existing data on microRNAs in TNBC, their molecular targets, a putative role in invasive progression with a particular emphasis on the epithelial-to-mesenchymal transition (EMT) and acquisition of stem-cell properties (CSC), regarded both as prerequisites for metastasis, and significance for therapy. Methods PubMed and Medline databases were systematically searched for the relevant literature. 121 articles have been selected and thoroughly analysed. Results Several miRNAs associated with EMT/CSC and invasion were identified as significantly (1) upregulated: miR-10b, miR-21, miR-29, miR-9, miR-221/222, miR-373 or (2) downregulated: miR-145, miR-199a-5p, miR-200 family, miR-203, miR-205 in TNBC. Dysregulation of miR-10b, miR-21, miR-29, miR-145, miR-200 family, miR-203, miR-221/222 was reported of prognostic value in TNBC patients. Conclusion Available data suggest that specific microRNA clusters might play an important role in biology of TNBC, understanding of which should assist disease prognostication and therapy.

Cadmium (Cd), a heavy metal with strong carcinogenic properties has been linked with breast cancer risk. Epidemiological data on the association between Cd exposure and breast cancer are not consistent and suggest that this relationship may be modulated by a number of different factors. The mechanisms of action underlying the molecular effects of Cd, especially in terms of its carcinogenicity, are generally not well understood. Specifically, in the mammary gland, the effects of Cd are considered to be related mainly to its oestrogenic potential, however, several other mechanisms have also been suggested, such as epigenetic alterations, inhibition of DNA repair pathways, induction of oxidative stress, interference with metallothioneins, cadherins and integrins, as well as interactions with xenobiotics. This review summarizes the current state of knowledge in this field, including potential mechanisms of action of Cd in breast cancer initiation and progression, as well as possible ways of protection against its toxicity. Importantly, there are many research gaps in this area since limited evidence is available from experimental studies. Important issues to be further investigated concern exact molecular mechanisms of Cd accumulation in the tissues and Cd-induced activation of eostrogen receptors. Impact on DNA damage and epigenome upon Cd exposure in breast cancer development remains still highly unexplored area and should gain more interest.

Genetic abnormalities provide vital diagnostic and prognostic information in pediatric acute lymphoblastic leukemia (ALL) and are increasingly used to assign patients to risk groups. We recently proposed a novel classifier based on the copy-number alteration (CNA) profile of the 8 most commonly deleted genes in B-cell precursor ALL. This classifier defined 3 CNA subgroups in consecutive UK trials and was able to discriminate patients with intermediate-risk cytogenetics. In this study, we sought to validate the United Kingdom ALL (UKALL)–CNA classifier and reevaluate the interaction with cytogenetic risk groups using individual patient data from 3239 cases collected from 12 groups within the International BFM Study Group. The classifier was validated and defined 3 risk groups with distinct event-free survival (EFS) rates: good (88%), intermediate (76%), and poor (68%) (P < .001). There was no evidence of heterogeneity, even within trials that used minimal residual disease to guide therapy. By integrating CNA and cytogenetic data, we replicated our original key observation that patients with intermediate-risk cytogenetics can be stratified into 2 prognostic subgroups. Group A had an EFS rate of 86% (similar to patients with good-risk cytogenetics), while group B patients had a significantly inferior rate (73%, P < .001). Finally, we revised the overall genetic classification by defining 4 risk groups with distinct EFS rates: very good (91%), good (81%), intermediate (73%), and poor (54%), P < .001. In conclusion, the UKALL-CNA classifier is a robust prognostic tool that can be deployed in different trial settings and used to refine established cytogenetic risk groups. Key Points The UKALL-CNA classifier is a validated and robust prognostic tool that can be deployed in a variety of clinical trial settings. The UKALL-CNA classifier can be used to refine risk stratification for patients with intermediate-risk cytogenetics. Visual Abstract

Immune checkpoint inhibitors (ICIs) are standard of care in advanced non-small cell lung cancer (NSCLC), however their status in patients with poor performance status (PS) is poorly defined. We aimed to evaluate the efficacy and safety of ICIs in NSCLC patients with PS ≥ 2. We conducted a systematic review and meta-analysis of interventional and observational studies, which reported efficacy and safety data on ICIs in PS ≥ 2 comparing to PS ≤ 1 NSCLC patients. Efficacy endpoints included: Objective Response Rate (ORR), Disease-Control Rate (DCR), Overall Survival (OS), Progression-Free Survival (PFS). Safety endpoint was the incidence of severe (grade≥3) Adverse Events (AE). Random-effects model was applied for meta-analysis. Heterogeneity was assessed using I2. The review is registered on PROSPERO (CRD42020162668). Sixty-seven studies (n = 26,442 patients) were included. In PS ≥ 2 vs. PS ≤ 1 patients, the pooled odds ratios were: for ORR 0.46 (95 %CI: 0.39-0.54, I2:0 %); for DCR 0.39 (95 %CI: 0.33-0.48, I2:50 %) and for AEs 1.12 (95 %CI: 0.84-1.48, I2:39 %). The pooled hazard ratio for PFS was 2.17 (95 %CI: 1.96-2.39, I2:65 %) and for OS was 2.76 (95 %CI: 2.43-3.14, I2:76 %). The safety profile was comparable regardless of the PS status. Patients with impaired PS status are, on average, twice less likely to achieve a response when exposed to ICIs when compared with representative PS ≤ 1 population. For lung cancer patients treated with ICIs, the impaired PS is not only prognostic, but also predictive for response, while the safety profile is not affected. Prospective randomized studies are indispensable to determine whether poor PS patients derive benefit from ICIs.