Michele Caraglia

Familial papillary thyroid microcarcinoma: a new clinical entity

BACKGROUND Familial, non-medullary thyroid carcinoma is clinically more aggressive than the sporadic form. We wanted to find out whether papillary thyroid microcarcinoma also occurs in a familial pattern, and, if so, to identify specific clinical and prognostic features. METHODS We reviewed the clinical records of 119 patients with papillary thyroid microcarcinoma. Familial occurrence, together with clinical presentation, surgical treatment, pathological characteristics, and follow-up were recorded. FINDINGS We identified a family history of thyroid carcinoma in seven patients. The tumour was multifocal in five patients, bilateral in three, and vascular invasion occurred in three of the seven patients. Lymph-node metastases were found in four patients. Three patients had a recurrence and one patient with pulmonary metastases died within 11 months. INTERPRETATION We identified familial occurrence in 5.9% of cases of papillary thyroid microcarcinoma. The unfavourable behaviour in the familial form of papillary thyroid microcarcinoma suggests that radical treatment and careful follow-up are warranted.

Repeated intermittent low-dose therapy with zoledronic acid induces an early, sustained, and long-lasting decrease of peripheral vascular endothelial growth factor levels in cancer patients.

Purpose: On the basis of stimulating data on animals reporting that weekly regimens of zoledronic acid (ZA) were effective in reducing skeletal tumor burden, we designed a study on humans to investigate the potential antiangiogenic role of a weekly low-dose therapy with ZA in patients with malignancies. Experimental Design: Twenty-six consecutive patients with advanced solid cancer and bone metastases received 1 mg of ZA every week for four times (days 1, 7, 14, and 21) followed by 4 mg of ZA with a standard 28-day schedule repeated thrice (days 28, 56, and 84). Patients were prospectively evaluated for circulating levels of vascular endothelial growth factor (VEGF) just before the beginning of drug infusion (0) and again at 7, 14, 21, 28, 56, and 84 days after the first ZA infusion. Results: The median VEGF basal value showed an early statistically significant (P = 0.038) decrease 7 days after the first 1-mg infusion of ZA. This effect on VEGF-circulating levels persisted also after the following 1-mg infusions at 14 (P = 0.002), 21 (P = 0.001), and 28 days (P = 0.008). Interestingly, the decrease of VEGF-circulating levels persisted also at each programmed time point during the second phase of the study (ZA 4 mg every 4 weeks). No significant differences were recorded in platelet levels, WBC count, or hemoglobin concentration before and after each ZA infusion. Conclusions: In the present study, we report that a repeated low-dose therapy with ZA is able to induce an early significant and long-lasting decrease of VEGF levels in cancer patients.

Molecular targets and oxidative stress biomarkers in hepatocellular carcinoma: an overview

Hepatocellular carcinoma (HCC) is a complex and heterogeneous tumor with multiple genetic aberrations. Several molecular pathways involved in the regulation of proliferation and cell death are implicated in the hepatocarcinogenesis. The major etiological factors for HCC are both hepatitis B virus (HBV) and hepatitis C virus infection (HCV).Continuous oxidative stress, which results from the generation of reactive oxygen species (ROS) by environmental factors or cellular mitochondrial dysfunction, has recently been associated with hepatocarcinogenesis. On the other hand, a distinctive pathological hallmark of HCC is a dramatic down-regulation of oxido-reductive enzymes that constitute the most important free radical scavenger systems represented by catalase, superoxide dismutase and glutathione peroxidase.The multikinase inhibitor sorafenib represents the most promising target agent that has undergone extensive investigation up to phase III clinical trials in patients with advanced HCC. The combination with other target-based agents could potentiate the clinical benefits obtained by sorafenib alone. In fact, a phase II multicenter study has demonstrated that the combination between sorafenib and octreotide LAR (So.LAR protocol) was active and well tolerated in advanced HCC patients.The detection of molecular factors predictive of response to anti-cancer agents such as sorafenib and the identification of mechanisms of resistance to anti-cancer agents may probably represent the direction to improve the treatment of HCC.

Critical role of both p27KIP1 and p21CIP1/WAF1 in the antiproliferative effect of ZD1839 ('Iressa'), an epidermal growth factor receptor tyrosine kinase inhibitor, in head and neck squamous carcinoma cells.

High expression of the epidermal growth factor receptor (EGFR) has been implicated in the development of squamous‐cell carcinomas of head and neck (SCCHN). ZD1839 (‘Iressa’) is an orally active, selective EGFR‐TKI (EGFR‐tyrosine kinase inhibitor) that blocks signal transduction pathways implicated in proliferation and survival of cancer cells, and other host‐dependent processes promoting cancer growth. We have demonstrated that ZD1839 induces growth arrest in SCCHN cell lines by inhibiting EGFR‐mediated signaling. Cell cycle kinetic analysis demonstrated that ZD1839 induces a delay in cell cycle progression and a G1 arrest together with a partial G2/M block; this was associated with increased expression of both p27KIP1 and p21CIP1/WAF1 cyclin‐dependent kinase (CDK) inhibitors. The activity of CDK2, the main target of CIP/KIP CDK inhibitors, was reduced in a dose‐dependent fashion after 24 h of ZD1839 treatment and this effect correlated to the increased amount of p27KIP1 and p21CIP1/WAF1 proteins associated with CDK2‐cyclin‐E and CDK2‐cyclin‐A complexes. In addition, ZD1839‐induced growth inhibition was significantly reduced in cell transfectants expressing p27KIP1 or p21CIP1/WAF1 antisense constructs. Overall, these results as well as the timing of the effect of ZD1839 on G1 arrest and p27KIP1 and p21CIP1/WAF1 upregulation, suggest a mechanistic connection between these events.

The translation elongation factor 1A in tumorigenesis, signal transduction and apoptosis: Review article

Summary.An increasing number of evidences suggest the involvement of the eukaryotic elongation factor 1A, a core component of the protein synthesis machinery, at the onset of cell transformation. In fact, eEF1A is shown to be up-regulated in cell death; moreover, it seems to be involved in the regulation of ubiquitin-mediated protein degradation. In addition, eEF1A undergoes several post-translational modifications, mainly phosphorylation and methylation, that generally influence the activity of the protein. This article summarizes the present knowledges on the several extra-translational roles of eEF1A also in order to understand as the protein synthesis regulatory mechanisms could offer tools for cancer intervention.

Zoledronic acid induces antiproliferative and apoptotic effects in human pancreatic cancer cells in vitro

Bisphosphonates (BPs) are an emerging class of drugs mostly used in the palliative care of cancer patients. We investigated the in vitro activity of the most potent antiresorptive BP, zoledronic acid (ZOL), on the growth and survival of three human pancreatic cancer (PC) cell lines (BxPC-3, CFPAC-1 and PANC-1). Pancreatic cancer frequently has a dysregulated p21ras pathway and therefore appears to be a suitable target for BPs that interfere with the prenylation of small GTP-binding proteins such as p21ras. We found that ZOL induces growth inhibition (IC50:10–50 μM) and apoptotic death of PC cells. The proapoptotic effect was correlated to cleavage/activation of caspase-9 and poly(ADP)-ribose polymerase, but not of caspase-3. Moreover, we studied the p21ras signalling in cells exposed to ZOL and detected a reduction of p21ras and Raf-1 content and functional downregulation of the terminal enzyme ERK/MAPkinase and of the pKB/Akt survival pathway. Finally, we observed that ZOL induces significant cytoskeletal rearrangements. In conclusion, we demonstrated that ZOL induces growth inhibition and apoptosis on PC cells and interferes with growth and survival pathways downstream to p21ras. These findings might be relevant for expanding application of BPs in cancer treatment.

Synthetic miR-34a Mimics as a Novel Therapeutic Agent for Multiple Myeloma: In Vitro and In Vivo Evidence

Purpose: Deregulated expression of miRNAs has been shown in multiple myeloma (MM). A promising strategy to achieve a therapeutic effect by targeting the miRNA regulatory network is to enforce the expression of miRNAs that act as tumor suppressor genes, such as miR-34a. Experimental Design: Here, we investigated the therapeutic potential of synthetic miR-34a against human MM cells in vitro and in vivo. Results: Either transient expression of miR-34a synthetic mimics or lentivirus-based miR-34a-stable enforced expression triggered growth inhibition and apoptosis in MM cells in vitro. Synthetic miR-34a downregulated canonic targets BCL2, CDK6, and NOTCH1 at both the mRNA and protein level. Lentiviral vector-transduced MM xenografts with constitutive miR-34a expression showed high growth inhibition in severe combined immunodeficient (SCID) mice. The anti-MM activity of lipidic-formulated miR-34a was further shown in vivo in two different experimental settings: (i) SCID mice bearing nontransduced MM xenografts; and (ii) SCID-synth-hu mice implanted with synthetic 3-dimensional scaffolds reconstituted with human bone marrow stromal cells and then engrafted with human MM cells. Relevant tumor growth inhibition and survival improvement were observed in mice bearing TP53-mutated MM xenografts treated with miR-34a mimics in the absence of systemic toxicity. Conclusions: Our findings provide a proof-of-principle that formulated synthetic miR-34a has therapeutic activity in preclinical models and support a framework for development of miR-34a–based treatment strategies in MM patients. Clin Cancer Res; 18(22); 6260–70. ©2012 AACR.

Early Skin Toxicity as a Predictive Factor for Tumor Control in Hepatocellular Carcinoma Patients Treated with Sorafenib

INTRODUCTION Sorafenib is an oral multikinase inhibitor that targets Raf kinase and receptor tyrosine kinases and has led to a longer median overall survival (OS) time and time to progression (TTP) in patients with advanced hepatocellular carcinoma (HCC). This study was conducted to assess the link between the antitumor efficacy of sorafenib and its early cutaneous side effects in advanced HCC patients. MATERIALS AND METHODS All patients received 800 mg daily of sorafenib until progression or unacceptable toxicities. We retrospectively analyzed the incidence of rash and hand-foot skin reactions (HFSR) during the first month of treatment, comparing tumor control (partial response plus stable disease) and TTP. RESULTS Sixty-five HCC patients treated with sorafenib were included in this analysis: 47 (73.3%) received sorafenib after failure of some local treatment, whereas 18 (27.7%) received it as first-line treatment. Twenty-nine patients developed at least grade 1 skin toxicity (rash, 13; HFSR, 16). In patients who developed skin toxicity, the tumor control rate was 48.3%, versus 19.4% in patients without cutaneous side effects. The median TTP was 8.1 months in the group of patients with skin toxicity versus 4.0 months in those without skin toxicity. This difference was also statistically significant on multivariate analysis. A borderline statistically significant difference was also observed in terms of OS in patients with early skin toxicity. CONCLUSIONS Skin toxicity should be closely monitored in HCC patients treated with sorafenib in relation to its potential role as a surrogate marker of efficacy.

Alpha‐interferon and its effects on signal transduction pathways

Interferon‐α (IFNα) is a recombinant protein widely used in the therapy of several neoplasms such as myeloma, renal cell carcinoma, epidermoid cervical and head and neck tumors, and melanoma. IFNα, the first cytokine to be produced by recombinant DNA technology, has emerged as an important regulator of cancer cell growth and differentiation, affecting cellular communication and signal transduction pathways. However, the way by which tumor cell growth is directly suppressed by IFNα is not well known. Wide evidence exists on the possibility that cancer cells undergo apoptosis after the exposure to the cytokine. Here we will review the consolidate signal transducer and activator of transcription (STAT)‐dependent mechanism of action of IFNα. We will discuss data obtained by us and others on the triggering of the stress‐dependent kinase pathway induced by IFNα and its correlations with the apoptotic process. The regulation of the expression of proteins involved in apoptosis occurrence will be also described. In this regard, IFNα is emerging as a post‐translational controller of the intracellular levels of the apoptosis‐related protein tissue transglutaminase (tTG). This new way of regulation of tTG occurs through the modulation of their proteasome‐dependent degradation induced by the cytokine. Until today, inconsistent data have been obtained regarding the clinical effectiveness of IFNα in the therapy of solid tumors. In fact, the benefit of IFNα treatment is limited to some neoplasms while others are completely or partially resistant. The mechanisms of tumor resistance to IFNα have been studied in vitro. The alteration of JAK‐STAT components of the IFNα‐induced signaling, can be indeed a mechanism of resistance to IFN. However, we have recently described a reactive mechanism of protection of tumor cells from the apoptosis induced by IFNα dependent on the epidermal growth factor (EGF)‐mediated Ras/extracellular signal regulated kinase (Erk) signaling. The involvement of the Ras→Erk pathway in the protection of tumor cells from the apoptosis induced by IFNα is further demonstrated by both Ras inactivation by RASN17 transfection and mitogen extracellular signal regulated kinase 1 (Mek‐1) inhibition by exposure to PD098059. These data strongly suggest that the specific disruption of the latter could be a useful approach to potentiate the antitumour activity of IFNα against human tumors based on the new mechanistic insights achieved in the last years.

Carbon nanotubes: Properties, biomedical applications, advantages and risks in patients and occupationally-exposed workers:

Since the beginning of the 21st century, carbon-based nanomaterials (CNTs) have been introduced in pharmacy and medicine for drug delivery system in therapeutics. CNTs have proved able to transport a wide range of molecules across membranes and into living cells; therefore, they have attracted great interest in biomedical applications such as advanced imaging, tissue regeneration, and drug or gene delivery. Although there are many data on the advantages in terms of higher efficacy and less adverse effects, several recent findings have reported unexpected toxicities induced by CNTs. The dose, shape, surface chemistry, exposure route, and purity play important roles in these differential toxicities. Mapping these risks as well as understanding their molecular mechanisms is a crucial step in the development of any CNT-containing nanopharmaceuticals. This paper seeks to provide a comprehensive review of all articles published on cellular response to CNTs, underlining their therapeutic applications and possible toxicity in patients and occupationally exposed workers.