Structure activity relationship studies on Amb639752: toward the identification of a common pharmacophoric structure for DGKα inhibitors.

A series of analogues of Amb639752, a novel diacylglycerol kinase (DGK) inhibitor recently discovered by us via virtual screening, have been tested. The compounds were evaluated as DGK inhibitors on α, θ, and ζ isoforms, and as antagonists on serotonin receptors. From these assays emerged two novel compounds, namely 11 and 20, which with an IC50 respectively of 1.6 and 1.8 µM are the most potent inhibitors of DGKα discovered to date. Both compounds demonstrated the ability to restore apoptosis in a cellular model of X-linked lymphoproliferative disease as well as the capacity to reduce the migration of cancer cells, suggesting their potential utility in preventing metastasis. Finally, relying on experimental biological data, molecular modelling studies allow us to set a three-point pharmacophore model for DGK inhibitors.

Port in oncology practice: 3-monthly locking with normal saline for catheter maintenance, a preliminary report.

INTRODUCTION: Patients with cancer need stable venous access using central vascular devices like central venous ports and peripherally inserted central catheters that can be used for a wide range of indications. Numerous flushing protocols exist including different frequencies for catheter locking to maintain catheter patency. The aim of this retrospective study was to evaluate the incidence of lumen occlusion of central venous ports in a group of adult cancer patients, adopting a policy of locking with normal saline every three months. METHODS: This is a single-center retrospective observational study. During follow-up, we analyzed adult cancer patients who had undergone port insertion from January 1st, 2007 to August 31st, 2014. Flushing and locking were performed every three months with a syringe containing normal saline. RESULTS: We collected data from 381 patients with ports inserted in subclavian vein (379 patients) and in the right jugular vein (2 patients). Locking was performed during 3-monthly follow-up visits. Median follow-up was 810 days (90-2700 days). Among 381 ports, 59 were removed; the reasons for removal were: end of use (45 cases), catheter rupture (9 cases), dislocation (3 cases) and catheter-related bloodstream infection (2 cases). We had no reports of lumen occlusion. CONCLUSIONS: Our data suggest that locking ports with normal saline every three months is not associated with an increased risk of lumen occlusion.

Resveratrol inhibits IL-6-induced ovarian cancer cell migration through epigenetic up-regulation of autophagy.

Interleukin-6 (IL-6), a pro-inflammatory cytokine released by cancer-associated fibroblasts, has been linked to the invasive and metastatic behavior of ovarian cancer cells. Resveratrol is a naturally occurring polyphenol with the potential to inhibit cancer cell migration. Here we show that Resveratrol and IL-6 affect in an opposite manner the expression of RNA messengers and of microRNAs involved in cell locomotion and extracellular matrix remodeling associated with the invasive properties of ovarian cancer cells. Among the several potential candidates responsible for the anti-invasive effect promoted by Resveratrol, here we focused our attention on ARH-I (DIRAS3), that encodes a Ras homolog GTPase of 26-kDa. This protein is known to inhibit cell motility, and it has been shown to regulate autophagy by interacting with BECLIN 1. IL-6 down-regulated the expression of ARH-I and inhibited the formation of LC3-positive autophagic vacuoles, while promoting cell migration. On opposite, Resveratrol could counteract the IL-6 induction of cell migration in ovarian cancer cells through induction of autophagy in the cells at the migration front, which was paralleled by up-regulation of ARH-I and down-regulation of STAT3 expression. Spautin 1-mediated disruption of BECLIN 1-dependent autophagy abrogated the effects of Resveratrol, while promoting cell migration. The present data indicate that Resveratrol elicits its anti-tumor effect through epigenetic mechanisms and support its inclusion in the chemotherapy regimen for highly aggressive ovarian cancers. © 2016 Wiley Periodicals, Inc.

Oligonucleotide Array-based Comparative Genomic Hybridization Approach in Hematologic Malignancies With Normal/Failed Conventional Cytogenetics and Fluorescent In Situ Hybridization.

Oligonucleotide array-based comparative genomic hybridization (oaCGH) was used to investigate 60 cases of hematologic malignancies, mainly acute myeloid leukemias and myelodysplastic syndromes, in order to evaluate its sensitivity and specificity and to search for genomic alterations undetected by previous investigation with conventional cytogenetics (CC) and fluorescent in situ hybridization (FISH). On the basis of CC and FISH results, we subdivided the series into group A (36 cases with a normal karyotype after CC and/or FISH testing) and group B (24 cases with anomalies detected by CC and/or FISH). oaCGH did not show alterations in 21 cases of the group A (58.3%); in the remaining 15 cases (41.7%), it detected 19 new abnormalities (14 amplifications and 5 deletions). In the group B, oaCGH confirmed 32/55 aneuploidies detected by FISH (58.1%). The sensitivity increased at 27/33 confirmed aneuploidies (81.8%) by placing as a cutoff a mosaic of 50%. Moreover, in the cases of this group oaCGH revealed 36 new alterations (15 amplifications and 21 deletions). From these results it is possible to assess a strong overlap between results obtained by FISH and oaCGH. However, oaCGH is a reliable alternative where CC and FISH are not feasible and is able to identify new alterations unexplored by FISH.

Primary Ewing's sarcoma of the sinonasal tract, eroding the ethmoid and sphenoid sinus with intracranial extension: A rare case report.

Ewing's sarcoma (ES) is an aggressive tumour that may present with skeletal and extraskeletal forms. The extraskeletal form is rarely encountered in the head and neck region and is extremely rare in the sinonasal tract. This is the case report of a ES of the ethmoid sinus with intracranial and orbital extension in a 33-year-old male patient who presented with anosmia, epistaxis, reduction of visual acuity in the left eye and headache. On otorhinolaryngological clinical examination and biopsy via flexible endoscope, the lesion was misdiagnosed as ethmoid sinus carcinoma. The subsequent magnetic resonance imaging (MRI) of the brain revealed a large mass (6×7 cm) eroding the ethmoid and sphenoid sinuses, extending beyond the orbits and occupying the anterior cranial fossa with a maximum extension of ~5 cm. The patient underwent surgical resection and the microscopic examination of the specimen established the diagnosis of ES (immunohistochemically positive for CD99, neuron-specific enolase, CD56, synaptophysin, pancytokeratin, low-molecular weight cytokeratins and vimentin. The periodic acid Schiff stain exhibited strong intracytoplasmic block positivity and fluorescence in situ hybridization revealed a t(22;11) translocation. First-line chemotherapy was administered for 3 cycles; however, on restaging MRI, local disease progression was diagnosed. The patient received radiotherapy and second-line chemotherapy for 6 cycles. At 15 months after the diagnosis, the patient remains recurrence-free and maintains a good functional status and quality of life.

PTEN deficiency and mutant p53 confer glucose-addiction to thyroid cancer cells: impact of glucose depletion on cell proliferation, cell survival, autophagy and cell migration.

Proliferating cancer cells oxidize glucose through the glycolytic pathway. Since this metabolism is less profitable in terms of ATP production, cancer cells consume large quantity of glucose, and those that experience insufficient blood supply become glucose-addicted. We have analyzed the response to glucose depletion in WRO and FTC133 follicular thyroid cancer cells, which differ in the expression of two key regulators of the glucose metabolism. WRO cells, which express wild type p53 and PTEN, showed a higher rate of cell proliferation and were much less sensitive to glucose-depletion than FTC133 cells, which are PTEN null and express mutant p53. Glucose depletion slowed-down the autophagy flux in FTC133 cells, not in WRO cells. In a wound-healing assay, WRO cells were shown to migrate faster than FTC133 cells. Glucose depletion slowed down the cell migration rate, and these effects were more evident in FTC133 cells. Genetic silencing of either wild-type PTEN or p53 in WRO cells resulted in increased uptake of glucose, whereas the ectopic expression of PTEN in FTC133 cells resulted in diminished glucose uptake. In conclusion, compared to WRO, FTC133 cells were higher glucose up-taker and consumer. These data do not support the general contention that cancer cells lacking PTEN or expressing the mutant p53R273H are more aggressive and prone to better face glucose depletion. We propose that concurrent PTEN deficiency and mutant p53 leads to a glucose-addiction state that renders the cancer cell more sensitive to glucose restriction. The present observation substantiates the view that glucose-restriction may be an adjuvant strategy to combat these tumours.

PTEN regulates plasma membrane expression of glucose transporter 1 and glucose uptake in thyroid cancer cells.

Glucose represents an important source of energy for the cells. Proliferating cancer cells consume elevated quantity of glucose, which is converted into lactate regardless of the presence of oxygen. This phenomenon, known as the Warburg effect, has been proven to be useful for imaging metabolically active tumours in cancer patients by (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET). Glucose is internalised in the cells by glucose transporters (GLUTs) belonging to the GLUT family. GLUT1 (SLC2A1) is the most prevalent isoform in more aggressive and less differentiated thyroid cancer histotypes. In a previous work, we found that loss of expression of PTEN was associated with increased expression of GLUT1 on the plasma membrane (PM) and probability of detecting thyroid incidentalomas by FDG-PET. Herein, we investigated the molecular pathways that govern the expression of GLUT1 on the PM and the glucose uptake in WRO (expressing WT PTEN) and FTC133 (PTEN null) follicular thyroid cancer cells cultured under glucose-depleted conditions. The membrane expression of GLUT1 was enhanced in glucose-deprived cells. Through genetic manipulations of PTEN expression, we could demonstrate that the lack of this oncosuppressor has a dominant effect on the membrane expression of GLUT1 and glucose uptake. We conclude that loss of function of PTEN increases the probability of cancer detection by FDG-PET or other glucose-based imaging diagnosis.

Autophagy and thyroid carcinogenesis: genetic and epigenetic links.

Thyroid cancer is the most common cancer of the endocrine system and is responsible for the majority of deaths from endocrine malignancies. Although a large proportion of thyroid cancers belong to well differentiated histologic subtypes, which in general show a good prognosis after surgery and radioiodine ablation, the treatment of radio-resistant papillary-type, of undifferentiated anaplastic, and of medullary-type thyroid cancers remains unsatisfactory. Autophagy is a vesicular process for the lysosomal degradation of protein aggregates and of damaged or redundant organelles. Autophagy plays an important role in cell homeostasis, and there is evidence that this process is dysregulated in cancer cells. Recent in vitro preclinical studies have indicated that autophagy is involved in the cytotoxic response to chemotherapeutics in thyroid cancer cells. Indeed, several oncogenes and oncosuppressor genes implicated in thyroid carcinogenesis also play a role in the regulation of autophagy. In addition, some epigenetic modulators involved in thyroid carcinogenesis also influence autophagy. In this review, we highlight the genetic and epigenetic factors that mechanistically link thyroid carcinogenesis and autophagy, thus substantiating the rationale for an autophagy-targeted therapy of aggressive and radio-chemo-resistant thyroid cancers.

Activity of weekly paclitaxel in advanced hormone-refractory prostate cancer.

OBJECTIVE: We evaluated efficacy and toxicity of weekly paclitaxel in metastatic hormone-refractory prostate cancer (HRPC). MATERIALS AND METHODS: Patients received weekly paclitaxel 80 mg/m2 by 1-hour intravenous infusion. A course of therapy consisted of 6 weekly treatments and 2 weeks rest. PSA response was defined as a PSA decrease not less than 50%, maintained for 4 weeks with stable or improved performance status. RESULTS: The study enrolled 43 patients with metastatic HRPC diagnosed a median of 10.5 months before. Median age was 69 years (range, 58-86 years). Five had previous radioisotopes treatment for bone pain, 15 had previous treatment of metastatic hormone-refractory disease, mainly estramustine. The median number of weeks of therapy delivered each patient was 8 (range, 1-24 weeks; cumulative, 369 weeks). PSA response was registered in 13 patients of 36 evaluable for PSA response (36.1%; 95% confidence interval [CI], 20.8-53.8), with a median duration of 4.2 months. Among 16 patients evaluable for objective response, 5 partial responses (31.2%; 95% CI, 11.0-58.7) and 9 stable diseases were registered. Eleven (42.3%) of 26 patients presenting with cancer-related symptoms had improvement. Median survival time was 12.8 months (95% CI, 10.1-15.5) Therapy was associated with acceptable hematological toxicity (anemia grade 3, 16%; neutropenia grade 3-4, 12%) and moderate nonhematologic toxicities (thrombosis/embolism 10%; fatigue all grades, 60%). CONCLUSION: Docetaxel every 3 weeks is the standard of care for metastatic HRPC, but our results suggest some activity and an acceptable toxicity of weekly paclitaxel.

Increased expression of HSP70 by colon cancer cells is not always associated with access to the dendritic cell cross-presentation pathway.

Dendritic cells (DCs) are highly specialized antigen-presenting cells endowed with the unique ability to not only present exogenous antigens upon exposure to MHC II, but also to cross-present these upon exposure to MHC I. This property was exploited to generate the tumor-specific CD8 cytotoxic lymphocyte (CTL) response in DCs-based cancer vaccine protocols. In this context, the source of tumor antigens remains a critical challenge. A crude tumor in the context of danger signals is believed to represent an efficient source of tumor antigens (TAs) for DCs loading. In our previous work, increased DCs cross-presentation of antigens from necrotic gastric carcinoma cells paralleled up-regulation of the heat shock protein hsp70. We studied the expression of hsp70 on primary colon carcinoma cells and its relevance in the cross-priming of anti-tumor CTL by tumor-loaded DCs. Hsp70 was expressed on all three of the tumors studied, but was never detected in the peritumoral normal mucosa (NM). The uptake of the tumor induced a trend towards down-modulation of the monocyte-specific marker CD14, but had no effect on the chemokine receptors CCR4 and CCR7. The IFN-gamma enzyme-linked immunospot assay (ELIspot) showed cross-priming of CTL by tumor-loaded but not NM-loaded DCs in four of the six cases studied. The CTL response generated in DC+tumor cultures was directed towards the tumor, but not towards NM, and it was characterized by refractoriness to polyclonal (Ca ionophores, PKC activators) stimuli. Of the three CTL-generating tumors, only one expressed hsp70. This data indicates a tumor-specific expression of hsp70, but does not support its relevance in the DC cross-presentation of TAs.

In vivo migration of labeled autologous natural killer cells to liver metastases in patients with colon carcinoma.

BACKGROUND: Besides being the effectors of native anti-tumor cytotoxicity, NK cells participate in T-lymphocyte responses by promoting the maturation of dendritic cells (DC). Adherent NK (A-NK) cells constitute a subset of IL-2-stimulated NK cells which show increased expression of integrins and the ability to adhere to solid surface and to migrate, infiltrate, and destroy cancer. A critical issue in therapy of metastatic disease is the optimization of NK cell migration to tumor tissues and their persistence therein. This study compares localization to liver metastases of autologous A-NK cells administered via the systemic (intravenous, i.v.) versus locoregional (intraarterial, i.a.) routes. PATIENTS AND METHODS: A-NK cells expanded ex-vivo with IL-2 and labeled with (111)In-oxine were injected i.a. in the liver of three colon carcinoma patients. After 30 days, each patient had a new preparation of (111)In-A-NK cells injected i.v. Migration of these cells to various organs was evaluated by SPET and their differential localization to normal and neoplastic liver was demonstrated after i.v. injection of 99mTc-phytate. RESULTS: A-NK cells expressed a donor-dependent CD56+ CD16+ CD3- (NK) or CD56+ CD16+ CD3+ (NKT) phenotype. When injected i.v., these cells localized to the lung before being visible in the spleen and liver. By contrast, localization of i.a. injected A-NK cells was virtually confined to the spleen and liver. Binding of A-NK cells to liver neoplastic tissues was observed only after i.a. injections. CONCLUSION: This unique study design demonstrates that A-NK cells adoptively transferred to the liver via the intraarterial route have preferential access and substantial accumulation to the tumor site.

Drug- and cell-mediated antitumor cytotoxicities modulate cross-presentation of tumor antigens by myeloid dendritic cells.

The way a tumor cell dies is believed to influence both its engulfment by dendritic cells (DC) and access of the relevant antigen(s) to the cross-presentation pathway. Here we have studied the effect of lymphokine activated killer (LAK) cells, gamma-radiation and the antimetabolite drug 5-fluorouracil (5-FU) on tumor uptake by HLA-matched DC, and DC presentation of tumor antigens to autologous T lymphocytes. LAK cells and radiation were the best inducers of apoptotic death (Annexin-V+/propidium iodide-) on the gastric cell line KATO III and a primary gastric carcinoma, respectively. The highest rate of tumor uptake by monocyte-derived, granulocyte macrophage colony stimulating factor/interleukin (IL)-4-driven DC was associated with 5-FU, followed by radiation. These treatments also induced high levels of heat shock protein (hsp70). In contrast, only DC that had been taken up 5-FU- or LAK-treated tumors up-modulated IL-12 and presented tumor-associated antigens with increased efficiency, as shown by class I MHC-restricted interferon-gamma release and cytotoxic responses by autologous lymphocytes. Together, these data indicate that apoptotic death induced by anti-cancer therapies can induce distinct patterns of class I MHC cross-presentation of gastric carcinoma-associated antigens to cytotoxic T lymphocyte precursors.

Influence of drug-induced apoptotic death on processing and presentation of tumor antigens by dendritic cells.

Here we have studied the effects of apoptotic cell death induced by chemotherapic agents on tumor phagocytosis by dendritic cells (DC) and presentation of the relevant antigen to T lymphocytes. Annexin-V-FITC (Ann-V) and propidium iodide (PI) staining was used to assess early apoptotic (Ann-V(+)/PI(-)) vs. late apoptotic/secondary necrotic (Ann-V(+)/PI(+)) death after a 24 hr observation of untreated and drug-treated gastric carcinoma cells. After treatments, the HLA-A*0201(+) tumor cell line KATO III was exposed for 24 hr to allogeneic, HLA-related GM-CSF, IL-4-driven immature (i) DC. Tumor-loaded iDC were tested for IL-12 release in an ELISA assay, incubated with the DC-maturating factor TNF-alpha and used as stimulators for autologous T lymphocytes. Generation of antitumor T response against KATO cells was evaluated in an anti-MHC class I MAb-blocked Interferon-gamma ELISPOT assay. After treatment with Cis-platin (cis), all dying cells were in early apoptosis, whereas secondary necrosis was the prevalent death pattern observed after epirubicin (epi) and doxorubicin (doxo). Doxo and epi increased tumor expression of heat shock protein (hsp) 70 and uptake of tumor cell components by DC, whereas cis treatment had no effect on hsp70 and was associated with poor tumor uptake by DC. Significant upmodulation of IL-12 was observed by DC that had taken up the doxo- and epi-treated tumors (p< 0.005 and p< 0.01, respectively). Increased IFN-gamma release was also observed after stimulation of T lymphocytes with DC loaded with doxo- and epi-treated (p< 0.02 and p< 0.005, respectively) but not with cis-treated DC. These data show that the products of early apoptosis cannot efficiently cross-activate MHC class I-restricted anti-tumor lymphocytes even in the presence of DC maturating factors, whereas secondary necrosis is associated with robust T cell response.