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Colorectal cancer (CRC) is the third most deadly cancer worldwide, and inflammatory bowel disease (IBD) is one of the critical factors in CRC carcinogenesis. IBD is responsible for an unphysiological and sustained chronic inflammation environment favoring the transformation. MicroRNAs (miRNAs) belong to a class of highly conserved short single-stranded segments (18–25 nucleotides) non-coding RNA and have been extensively discussed in both CRC and IBD. However, the role of miRNAs in the development of colitis-associated CRC (CAC) is less clear. The aim of this review is to summarize the major upregulated (miR-18a, miR-19a, miR-21, miR-31, miR-155 and miR-214) and downregulated (miR-124, miR-193a-3p and miR-139-5p) miRNAs in CAC, and their roles in genes’ expression modulation in chronic colonic-inflammation-induced carcinogenesis, including programmed cell-death pathways. These miRNAs dysregulation could be applied for early CAC diagnosis, to predict therapy efficacy and for precision treatment.

Head and neck squamous cell carcinoma (HNSCC), a heterogeneous disease arising from various anatomical locations including the larynx, is a leading cause of death worldwide. Despite advances in multimodality treatment, the overall survival rate of the disease is still largely dismal. Early and accurate diagnosis of HNSCC is urgently demanded in order to prevent cancer progression and to improve the quality of the patient’s life. Recently, microRNAs (miRNAs), a family of small non-coding RNAs, have been widely reported as new robust tools for prediction, diagnosis, prognosis, and therapeutic approaches of human diseases. Abnormally expressed miRNAs are strongly associated with cancer development, resistance to chemo-/radiotherapy, and metastatic potential through targeting a large variety of genes. In this review, we summarize on the recent reports that emphasize the pivotal biological roles of miRNAs in regulating carcinogenesis of HNSCC, particularly laryngeal cancer. In more detail, we report the characterized miRNAs with an evident either oncogenic or tumor suppressive role in the cancers. In addition, we also focus on the correlation between miRNA deregulation and clinical relevance in cancer patients. On the basis of intriguing findings, the study of miRNAs will provide a new great opportunity to access better clinical management of the malignancies.

Farnesyl pyrophosphate synthase (FPPS) is a crucial enzyme for the synthesis of isoprenoids and the key target of nitrogen-containing bisphosphonates (N-BPs). N-BPs are potent and selective FPPS inhibitors that are used in the treatment of bone-related diseases, but have poor pharmacokinetic properties. Given the key role played by FPPS in many cancer-related pathways and the pharmacokinetic limits of N-BPs, hundreds of molecules have been screened to identify new FPPS inhibitors characterized by improved drug-like properties that are useful for broader therapeutic applications in solid, non-skeletal tumours. We have previously shown that N6-isopentenyladenosine (i6A) and its related compound N6-benzyladenosine (2) exert anti-glioma activity by interfering with the mevalonate pathway and inhibiting FPPS. Here, we report the design and synthesis of a panel of N6-benzyladenosine derivatives (compounds 2a-m) incorporating different chemical moieties on the benzyl ring. Compounds 2a-m show in vitro antiproliferative activity in U87MG glioma cells and, analogous to the bisphosphonate FPPS inhibitors, exhibit immunogenic properties in ex vivo γδ T cells from stimulated peripheral blood mononuclear cells (PBMCs). Using saturation transfer difference (STD) and quantitative 1H nuclear magnetic resonance (NMR) experiments, we found that 2f, the N6-benzyladenosine analogue that includes a tertbutyl moiety in the para position of the benzyl ring, is endowed with increased FPPS binding and inhibition compared to the parent compounds i6A and 2. N6-benzyladenosine derivatives, characterized by structural features that are significantly different from those of N-BPs, have been confirmed to be promising chemical scaffolds for the development of non N-BP FPPS inhibitors, exerting combined cytotoxic and immunostimulatory activities.

// Donatella Malanga 1 , Carmela De Marco 1, 2 , Ilaria Guerriero 2 , Fabiana Colelli 2 , Nicola Rinaldo 2 , Marianna Scrima 1, 2 , Teresa Mirante 3 , Claudia De Vitis 7 , Pietro Zoppoli 2 , Michele Ceccarelli 1, 4 , Miriam Riccardi 1, 2 , Maria Ravo 5 , Alessandro Weisz 5 , Antonella Federico 6 , Renato Franco 7 , Gaetano Rocco 7 , Rita Mancini 8 , Antonia Rizzuto 3 , Elio Gulletta 9 , Gennaro Ciliberto 7 , Giuseppe Viglietto 1, 2 1 Dipartimento di Medicina Sperimentale e Clinica, Universita Magna Graecia, Catanzaro, Italy 2 Biogem scarl, Istituto di Ricerche Genetiche, Ariano Irpino (Avellino), Italy 3 Dipartimento di Scienze Mediche e Chirurgiche, Universita Magna Graecia, Catanzaro, Italy 4 Dipartimento di Scienze e Tecnologie, Universita del Sannio, Benevento, Italy 5 Dipartimento di Medicina e Chirurgia, Universita di Salerno, Baronissi, Italy 6 Dipartimento di Dipartimento di Medicina Molecolare e Biotecnologie Mediche, Universita Federico II, Napoli, Italy 7 IRCCS Istituto Nazionale Tumori Fondazione G. Pascale, Napoli, Italy 8 Dipartimento di Medicina Clinica e Molecolare, Universita di Roma “La Sapienza” Ospedale S. Andrea, Roma, Italy 9 Dipartimento di Scienze della Salute, Universita Magna Graecia, Catanzaro, Italy Correspondence to: Giuseppe Viglietto, e-mail: viglietto@unicz.it Keywords: NSCLC, tumor initiating cells, Akt1, IL-6, STAT3 Received: June 15, 2015 Accepted: September 09, 2015 Published: October 13, 2015 ABSTRACT Here we report that the PI3K/Akt1/IL-6/STAT3 signalling pathway regulates generation and stem cell-like properties of Non-Small Cell Lung Cancer (NSCLC) tumor initiating cells (TICs). Mutant Akt1, mutant PIK3CA or PTEN loss enhances formation of lung cancer spheroids (LCS), self-renewal, expression of stemness markers and tumorigenic potential of human immortalized bronchial cells (BEAS-2B) whereas Akt inhibition suppresses these activities in established (NCI-H460) and primary NSCLC cells. Matched microarray analysis of Akt1-interfered cells and LCSs identified IL-6 as a critical target of Akt signalling in NSCLC TICs. Accordingly, suppression of Akt in NSCLC cells decreases IL-6 levels, phosphorylation of IkK and IkB, NF-kB transcriptional activity, phosphorylation and transcriptional activity of STAT3 whereas active Akt1 up-regulates them. Exposure of LCSs isolated from NSCLC cells to blocking anti-IL-6 mAbs, shRNA to IL-6 receptor or to STAT3 markedly reduces the capability to generate LCSs, to self-renew and to form tumors, whereas administration of IL-6 to Akt-interfered cells restores the capability to generate LCSs. Finally, immunohistochemical studies in NSCLC patients demonstrated a positive correlative trend between activated Akt, IL-6 expression and STAT3 phosphorylation ( n = 94; p < 0.05). In conclusion, our data indicate that aberrant Akt signalling contributes to maintaining stemness in lung cancer TICs through a NF-kB/IL-6/STAT3 pathway and provide novel potential therapeutic targets for eliminating these malignant cells in NSCLC.

Analogs of potent CaMKinase II inhibitor, CaM-KNtide, were prepared to explore new structural requirements for the inhibitory activity. The full potency of CaMKII inhibition by CaM-KIINα is contained within a minimal region of 19 amino acids. Here, analysis of the homologous CaM-KIINβ showed that a 17 mer peptide (CN17β) was the shortest sequence that still retained useful inhibitory potency. Ala substitution of almost any residue of CN17β dramatically reduced potency, except for substitution of P3, R14, and V16. Fusion with the tat sequence generated the cell-penetrating inhibitor version tat-5. This tat-5 fusion peptide maintained selectivity for CaMKII over CaMKI and CaMKIV, and appeared to slightly further enhance potency (IC(50) ∼30 nM). Within a breast cancer cell line and in primary human fibroblasts, tat-5 inhibited the Erk signaling pathway and proliferation without any measurable cytotoxicity. Structural analysis of CN17β by CD and NMR indicated an α-helix conformation in the Leu6-Arg11 segment well overlapping with the crystal structure of 21-residue segment of CaM-KNtide bound to the kinase domain of CaMKII.

We previously reported that CSF114(Glc) detects diagnostic autoantibodies in multiple sclerosis sera. We report herein a bioinformatic analysis of myelin proteins and CSF114(Glc), which led to the identification of five sequences. These glucopeptides were synthesized and tested in enzymatic assays, showing a common minimal epitope. Starting from that, we designed an optimized sequence, SP077, showing a higher homology with both CSF114(Glc) and the five sequences selected using the bioinformatic approach. SP077 was synthesized and tested on 50 multiple sclerosis patients' sera, and was able to detect higher antibody titers as compared to CSF114(Glc). Finally, the conformational properties of SP077 were studied by NMR spectroscopy and structure calculations. Thus, the immunological activity of SP077 in the recognition of specific autoantibodies in multiple sclerosis patients' sera may be ascribed to both the optimized design of its epitopic region and the superior surface interacting properties of its C-terminal region.

The aim of the present work was to identify protein tyrosine phosphatases (PTPs) as novel, candidate tumor suppressor genes in lung cancer. Among the 38 PTPs in the human genome that show specificity for phosphotyrosine, we identified six PTPs by quantitative RT-PCR whose mRNA expression levels were significantly down-regulated in lung cancer–derived cell lines (ie, PTPRE, PTPRF, PTPRU, PTPRK, PTPRD, and PTPN13). After validation in primary samples of non–small cell lung cancer (NSCLC), we selected PTPN13 for further studies. The results presented here demonstrate that PTPN13 is a candidate tumor suppressor gene that is frequently inactivated in NSCLC through the loss of either mRNA and protein expression (64/87, 73%) or somatic mutation (approximately 8%). Loss of PTPN13 expression was apparently due to the loss of one or both copies of the PTPN13 locus at 4q (approximately 26% double deletion and approximately 37% single deletion) but not to promoter methylation. Finally, the manipulation of PTPN13 expression in lung cancer cells (ie, NCI-H292, A549) demonstrated that PTPN13 negatively regulates anchorage-dependent and anchorage-independent growth in vitro and restrains tumorigenicity in vivo , possibly through the control of the tyrosine phosphorylation of both EGFR and HER2. In conclusion, the expression screening of PTPs in lung cancer reported here has identified PTPN13 as a novel candidate tumor suppressor in NSCLC whose loss increases signaling from epidermal growth factor receptor and HER2 tyrosine kinase receptors.

Loss of the PTEN tumor suppressor gene occurs frequently in non-small-cell lung carcinoma (NSCLC), although neither genetic alterations nor epigenetic silencing are significant predictors of PTEN protein levels. Since recent reports implicated neural precursor cell expressed, developmentally down-regulated 4-1 (NEDD4-1) as the E3 ubiquitin ligase that regulates PTEN stability, we investigated the role of NEDD4-1 in the regulation of PTEN expression in cases of NSCLC. Our findings indicate that NEDD4-1 plays a critical role in the development of NSCLC and provides novel insight on the mechanisms that contribute to inactivate PTEN in lung cancer. Immunohistochemical analysis on tissue microarrays containing 103 NSCLC resections revealed NEDD4-1 overexpression in 80% of tumors, which correlated with the loss of PTEN protein (n = 98; P < 0.001). Accordingly, adoptive NEDD4-1 expression in NSCLC cells decreased PTEN protein stability, whereas knock-down of NEDD4-1 expression decreased PTEN ubiquitylation and increased PTEN protein levels. In 25% of cases, NEDD4-1 overexpression was due to gene amplification at 15q21. In addition, manipulation of NEDD4-1 expression in different lung cell systems demonstrated that suppression of NEDD4-1 expression significantly reduced proliferation of NSCLC cells in vitro and tumor growth in vivo, whereas NEDD4-1 overexpression facilitated anchorage-dependent and independent growth in vitro of nontransformed lung epithelial cells that lack pRB and TP53 (BEAS-2B). NEDD4-1 overexpression also augmented the tumorigenicity of lung cancer cells that have an intact PTEN gene (NCI-H460 cells).