Liquid biopsy for rectal cancer: a systematic review

Background: The management of locally advanced rectal cancer (RC) is an evolving clinical field where the multidisciplinary approach can reach its best, and liquid biopsy for obtaining tumor-derived component such as circulating tumor DNA (ctDNA) might provide complementary informations. Methods: A systematic review of studies available in literature of liquid biopsy in non-metastatic RC has been performed according to PRISMA criteria to assess the role of ctDNA as a diagnostic, predictive and prognostic biomarker in this setting. Results: Twenty-five publications have been retrieved, of which 8 full-text articles, 7 abstracts and 10 clinical trials. Results have been categorized into three groups: diagnostic, predictive and prognostic. Few but promising data are available about the use of liquid biopsy for early diagnosis of RC, with the main limitation of sensitivity due to low concentrations of ctDNA in this setting. In terms of prediction of response to chemoradiation, still inconclusive data are available about the utility of a pre-treatment liquid biopsy, whereas some studies report a positive correlation with a dynamic (pre/post-treatment) monitoring. The presence of minimal residual disease by ctDNA was consistently associated with worse prognosis across studies. Conclusions: The use of liquid biopsy for monitoring response to chemoradiation and assess the risk of disease recurrence are the most advanced potential applications for liquid biopsy in RC, with implications also in the context of non-operative management strategies

Alexithymia and personality traits of patients with inflammatory bowel disease

Psychological factors, specific lifestyles and environmental stressors may influence etiopathogenesis and evolution of chronic diseases. We investigate the association between Chronic Inflammatory Bowel Diseases (IBD) and psychological dimensions such as personality traits, defence mechanisms, and Alexithymia, i.e. deficits of emotional awareness with inability to give a name to emotional states. We analyzed a survey of 100 patients with IBD and a control group of 66 healthy individuals. The survey involved filling out clinical and anamnestic forms and administering five psychological tests. These were then analyzed by using a network representation of the system by considering it as a bipartite network in which elements of one set are the 166 individuals, while the elements of the other set are the outcome of the survey. We then run an unsupervised community detection algorithm providing a partition of the 166 participants into clusters. That allowed us to determine a statistically significant association between psychological factors and IBD. We find clusters of patients characterized by high neuroticism, alexithymia, impulsivity and severe physical conditions and being of female gender. We therefore hypothesize that in a population of alexithymic patients, females are inclined to develop psychosomatic diseases like IBD while males might eventually develop behavioral disorders

Adipose-Derived Stem Cells from Fat Tissue of Breast Cancer Microenvironment Present Altered Adipogenic Differentiation Capabilities

Mesenchymal stem cells (MSCs) are multipotent cells able to differentiate into multiple cell types, including adipocytes, osteoblasts, and chondrocytes. The role of adipose-derived stem cells (ADSCs) in cancers is significantly relevant. They seem to be involved in the promotion of tumour development and progression and relapse processes. For this reason, investigating the effects of breast cancer microenvironment on ADSCs is of high importance in order to understand the relationship between tumour cells and the surrounding stromal cells. With the current study, we aimed to investigate the specific characteristics of human ADSCs isolated from the adipose tissue of breast tumour patients. We compared ADSCs obtained from periumbilical fat (PF) of controls with ADSCs obtained from adipose tissue of breast cancer- (BC-) bearing patients. We analysed the surface antigens and the adipogenic differentiation ability of both ADSC populations. C/EBP\u3b4 expression was increased in PF and BC ADSCs induced to differentiate compared to the control while PPAR\u3b3 and FABP4 expressions were enhanced only in PF ADSCs. Conversely, adiponectin expression was reduced in PF-differentiated ADSCs while it was slightly increased in differentiated BC ADSCs. By means of Oil Red O staining, we further observed an impaired differentiation capability of BC ADSCs. To investigate this aspect more in depth, we evaluated the effect of selective PPAR\u3b3 activation and nutritional supplementation on the differentiation efficiency of BC ADSCs, noting that it was only with strong differentiation stimuli that the process took place. Furthermore, we observed no response in BC ADSCs to the PPAR\u3b3 inhibitor T0070907, showing an impaired activation of this receptor in adipose cells surrounding the breast cancer microenvironment. In conclusion, our study shows an impaired adipogenic differentiation capability in BC ADSCs. This suggests that the tumour microenvironment plays a key role in the modulation of the adipose microenvironment located in the surrounding tissue

Impact of hypoxia on chemoresistance of mesothelioma mediated by the proton-coupled folate transporter, and preclinical activity of new anti-LDH-A compounds

BACKGROUND: Expression of proton-coupled folate transporter (PCFT) is associated with survival of mesothelioma patients treated with pemetrexed, and is reduced by hypoxia, prompting studies to elucidate their correlation. METHODS: Modulation of glycolytic gene expression was evaluated by PCR arrays in tumour cells and primary cultures growing under hypoxia, in spheroids and after PCFT silencing. Inhibitors of lactate dehydrogenase (LDH-A) were tested in vitro and in vivo. LDH-A expression was determined in tissue microarrays of radically resected malignant pleural mesothelioma (MPM, N = 33) and diffuse peritoneal mesothelioma (DMPM, N = 56) patients. RESULTS: Overexpression of hypoxia marker CAIX was associated with low PCFT expression and decreased MPM cell growth inhibition by pemetrexed. Through integration of PCR arrays in hypoxic cells and spheroids and following PCFT silencing, we identified the upregulation of LDH-A, which correlated with shorter survival of MPM and DMPM patients. Novel LDH-A inhibitors enhanced spheroid disintegration and displayed synergistic effects with pemetrexed in MPM and gemcitabine in DMPM cells. Studies with bioluminescent hypoxic orthotopic and subcutaneous DMPM athymic-mice models revealed the marked antitumour activity of the LDH-A inhibitor NHI-Glc-2, alone or combined with gemcitabine. CONCLUSIONS: This study provides novel insights into hypoxia/PCFT-dependent chemoresistance, unravelling the potential prognostic value of LDH-A, and demonstrating the preclinical activity of LDH-A inhibitors

The prognostic role of KRAS and BRAF in patients undergoing surgical resection of colorectal cancer liver metastasis: a systematic review and meta-analysis

Background: Clinical trials investigated the potential role of both KRAS and BRAF mutations, as prognostic biomarkers, in colorectal cancer (CRC) patients who underwent surgical treatment of liver metastasis (CLM), showing conflicting results. This meta-analysis aims to review all the studies reporting survival outcomes (recurrence free survival (RFS), and/or overall survival (OS)) of patients undergoing resection of CLM, stratified according to KRAS and/or BRAF mutation status. Materials and Methods: Data from all published studies reporting survival outcomes (RFS and/or OS) of CRC patients who received resection of CLM, stratified by KRAS and/or BRAF mutation status were collected by searching in PubMed, Cochrane Library, American Society of Clinical Oncology and European Society of Medical Oncology meeting proceedings. Pooled hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated for both the OS and/or RFS. Results: Seven eligible trials (1403 patients) were included. Pooled analysis showed that KRAS mutations predicted a significant worse both RFS (HR: 1.65; 95% CI: 1.23 \u2013 2.21) and OS (HR: 1.86; 95% CI: 1.51 \u2013 2.30) in patients who underwent surgical resection of CLM. BRAF mutations were also associated with a significant worse OS (HR: 3.90; 95% CI: 1.96 \u2013 7.73) in this subgroup of patients. Conclusion: This meta-analysis suggests both KRAS and BRAF mutations as negative prognostic biomarkers associated with worse survival outcomes in patients undergoing hepatic resection of CLM. Such evidences support the introduction of new treatment decision models, taking into account the tumor molecular profile in order to individualize both systemic and loco-regional treatment strategies

Effects of Dietary Restriction on Cancer Development and Progression

The effects of caloric restriction on tumor growth and progression are known for over a century. Indeed, fasting has been practiced for millennia, but just recently has emerged the protective role that it may exert toward cells. Fasting cycles are able to reprogram the cellular metabolism, by inducing protection against oxidative stress and prolonging cellular longevity. The reduction of calorie intake as well as short- or long-term fasting has been shown to protect against chronic and degenerative diseases, such as diabetes, cardiovascular pathologies, and cancer. In vitro and in vivo preclinical models showed that different restriction dietary regimens may be effective against cancer onset and progression, by enhancing therapy response and reducing its toxic side effects. Fasting-mediated beneficial effects seem to be due to the reduction of inflammatory response and downregulation of nutrient-related signaling pathways able to modulate cell proliferation and apoptosis. In this chapter, we will discuss the most significant studies present in literature regarding the molecular mechanisms by which dietary restriction may contribute to prevent cancer onset, reduce its progression, and positively affect the response to the treatments

Liquid Biopsy in Non-Small Cell Lung Cancer (NSCLC)

Lung cancer is the leading cause of cancer deaths worldwide. To date, the gold standard for the molecular analysis of a patient affected by NSCLC is the tissue biopsy. The discovery of activating mutations and rearrangements in specific genes has revolutionized the therapeutic approaches of lung cancer over the last years. For this reason, a strict \u201cmolecular follow-up\u201d is mandatory to evaluate patient\u2019s disease evolution. Indeed, liquid biopsy has raised as the \u201cnew ambrosia of researchers\u201d as it could help clinicians to identify both prognostic and predictive biomarkers in a more accessible way. Liquid biopsy analysis can be used in different moments starting from diagnosis to relapse, earning multiple clinical meanings, offering thus a noninvasive but valid method to detect actionable mutations. Although the implementation of both exosomes and CTCs in clinical practice is several steps back, new advances and discoveries make them, together with the ctDNA, a very promising tool. In the following chapter we will discuss the recent advances of liquid biopsy in NSCLC highlighting the possible clinical utility of CTCs, ctDNA and exosomes

Impact of phospho-Akt expression on the clinical outcome and activity of gemcitabine and Akt inhibitors in pancreatic ductal adenocarcinoma

Background: Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal solid tumors. Despite extensive preclinical and clinical research, the prognosis of this disease has not significantly improved, with a 5-year survival rate around 7%. There is an urgent need to better understand the molecular pathology of PDAC in order to improve patient selection for current treatment options and to develop novel therapeutic strategies. The PI3K/AKT/mTOR pathway plays a crucial role in PDAC: activation of Akt is a frequent event and has been correlated to poor prognosis and resistance to chemotherapy. Against this background, effective blockage of Akt signaling can lead to programmed cell death and inhibition of tumor growth. Several inhibitors of Akt under investigation include perifosine, which prevents Akt translocation to the cell membrane, MK-2206 which is an Akt allosteric inhibitor and BEZ-235 which is a dual PI3K/ mTOR inhibitor. The aims of this study were to investigate 1) the prognostic role of Akt in PDAC tissues and 2) the molecular mechanisms underlying the interaction of Akt inhibitors with gemcitabine in PDAC cells and primary cultures. Materials and methods: Immunohistochemistry of tissue microarrays with specimens from radically-resected patients (n ¼ 100) revealed a correlation between high phospho-Akt1 expression and worse outcome. Patients with low expression had a median overall survival (OS) of 16.2 months (95%CI, 14.8-20.1), while patients with high expression had a median OS of 12.0 months (95%CI, 9.0-14.9, P ¼ 0.03). Results: Akt inhibitors synergistically enhanced the antiproliferative activity of gemcitabine in the LPC028 primary cells, characterized by high expression levels, while this combination was antagonistic in LPC006 cells, characterized by low expression levels. Inhibition of Akt decreased cell migration and invasion, which was additionally reduced by the combination with gemcitabine. However, the combination of Akt inhibitors with gemcitabine significantly increased apoptosis, associated with induction of caspase-3/6/8/9, PARP and BAD, and inhibition of Bcl-2 and NF-kB in LPC028, but not in LPC006 cells. Conclusions: Our results support the analysis of phospho-Akt as a new biomarker both for PDAC prognosis and for the development of new therapeutic approaches. In particular, perifosine interact synergistically with gemcitabine in cells with phosphoAkt overexpressio