PubMed Health⌕ Search

Biomedical subjects

Simone Mocellin

Publications and source records attributed to Simone Mocellin.

At least 37 records · Page 2Linked to original sources

DNA array-based gene profiling: from surgical specimen to the molecular portrait of cancer.

Cancer is a heterogeneous disease in most respects, including its cellularity, different genetic alterations, and diverse clinical behaviors. Traditional molecular analyses are reductionist, assessing only 1 or a few genes at a time, thus working with a biologic model too specific and limited to confront a process whose clinical outcome is likely to be governed by the combined influence of many genes. The potential of functional genomics is enormous, because for each experiment, thousands of relevant observations can be made simultaneously. Accordingly, DNA array, like other high-throughput technologies, might catalyze and ultimately accelerate the development of knowledge in tumor cell biology. Although in its infancy, the implementation of DNA array technology in cancer research has already provided investigators with novel data and intriguing new hypotheses on the molecular cascade leading to carcinogenesis, tumor aggressiveness, and sensitivity to antiblastic agents. Given the revolutionary implications that the use of this technology might have in the clinical management of patients with cancer, principles of DNA array-based tumor gene profiling need to be clearly understood for the data to be correctly interpreted and appreciated. In the present work, we discuss the technical features characterizing this powerful laboratory tool and review the applications so far described in the field of oncology.

Antineoplastic Agents↗

Search for melanoma markers in plasma and serum samples.

Fourteen blood samples from patients with melanoma and eleven blood samples from healthy subjects were analyzed by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry. The study was focussed on species of low molecular weight, in the range 800-5000 Da, present in plasma and sera. While for healthy subjects plasma samples lead to the production of a higher number of ionic species, for melanoma patients a high number of diagnostic ions, present with high frequency and with quite high relative abundance, are present in particular in serum samples and to a lesser extent also in plasma. Since plasma samples are obtained more easily in comparison to sera, it is possible to suggest that also plasma can be used for these studies.

Adult↗

Priming anticancer active specific immunotherapy with dendritic cells.

Dendritic cells (DCs) probably represent the most powerful naturally occurring immunological adjuvant for anticancer vaccines. However, the initial enthusiasm for DC-based vaccines is being tempered by clinical results not meeting expectations. The partial failure of current vaccine formulations is explained by the extraordinary complexity of the immune system, which makes the task of exploiting the potential of such a biotherapeutic approach highly challenging. Clinical findings obtained in humans so far indicate that the immune system can be actively polarized against malignant cells by means of DC-based active specific immunotherapy, and that in some cases this is associated with tumor regression. This implies that under some unique circumstances, the naturally 'dormant' immune effectors can actually be employed as endogenous weapons against malignant cells. Only the thorough understanding of DC biology and tumor-host immune system interactions will allow researchers to reproduce, in a larger set of patients, the cellular/molecular conditions leading to an effective immune-mediated eradication of cancer.

Animals↗

Tumor necrosis factor, cancer and anticancer therapy.

Tumor necrosis factor (TNF) is being utilized as an antineoplastic agent for the treatment of patients with locally advanced solid tumors. However, its role in cancer therapy is debated. Although a large body of evidence supports TNF's antineoplastic activity, the cascade of molecular events underlying TNF-mediated tumor regression observed in vivo is still incompletely elucidated. Intriguingly, some pre-clinical findings suggest that TNF may promote cancer development and progression, which has led to propose anti-TNF therapy as a novel approach to malignancies. In the present work, we summarize the molecular biology of TNF with particular regard to its tumor-related properties, and review the experimental and clinical evidence currently available describing the complex and sometime conflicting relationship between this cytokine, cancer and antitumor therapy. Recent insights that might pave the way to further exploitation of the antineoplastic potential of TNF are also discussed.

Antineoplastic Agents↗

RNA interference: learning gene knock-down from cell physiology.

SUMMARY: Over the past decade RNA interference (RNAi) has emerged as a natural mechanism for silencing gene expression. This ancient cellular antiviral response can be exploited to allow specific inhibition of the function of any chosen target gene. RNAi is proving to be an invaluable research tool, allowing much more rapid characterization of the function of known genes. More importantly, RNAi technology considerably bolsters functional genomics to aid in the identification of novel genes involved in disease processes.This review briefly describes the molecular principles underlying the biology of RNAi phenomenon and discuss the main technical issues regarding optimization of RNAi experimental design.

Journal Article↗

Induction of endothelial nitric oxide synthase expression by melanoma sensitizes endothelial cells to tumor necrosis factor-driven cytotoxicity.

PURPOSE: The cascade of molecular events leading to tumor necrosis factor (TNF)-mediated tumor regression is still incompletely elucidated. We investigated the role of endothelial nitric oxide synthase in determining the tumor-selective activity of TNF. EXPERIMENTAL DESIGN: Using quantitative real-time PCR, endothelial nitric oxide synthase gene levels were measured in melanoma metastases of the skin and normal skin biopsies obtained from 12 patients before undergoing TNF-based therapy. In vitro, the ability of melanoma cells supernatant to affect endothelial nitric oxide synthase transcription by endothelial cells and the influence of nitric oxide synthase inhibition on TNF cytotoxicity toward endothelial cells was evaluated. RESULTS: Endothelial nitric oxide synthase transcript abundance resulted significantly greater in tumor samples rather than in normal skin samples and in patients showing complete response to TNF-based treatment rather than in those showing partial/minimal response. In vitro, melanoma cells' supernatant induced endothelial nitric oxide synthase gene expression by endothelial cells. Nitric oxide synthase inhibition slowed endothelial cells proliferation and, if induced before TNF administration, decreased the cytokine-mediated cytotoxicity on endothelial cells. CONCLUSIONS: Taken together, these findings support the hypothesis that high expression of endothelial nitric oxide synthase in the tumor microenvironment might increase or be a marker for endothelial cells sensitivity to TNF. These observations may have important prognostic and/or therapeutic implications in the clinical setting.

Biopsy↗

Cancer vaccine development: on the way to break immune tolerance to malignant cells.

Exploiting a naturally occurring defense system, the immunotherapeutic approach embodies an ideal nontoxic treatment for cancer. Despite the evidence that immune effectors can play a significant role in controlling tumor growth either in natural conditions or in response to therapeutic manipulation, the cascade of molecular events leading to tumor rejection by the immune system remains to be fully elucidated. Nevertheless, some recent tumor immunology advancements might drastically change the way to design the next generation of cancer vaccines, hopefully improving the effectiveness of this therapeutic approach. In the present work, we will focus on three main areas of particular interest for the development of novel vaccination strategies: (a) cellular or molecular mechanisms of immune tolerance to malignant cells; (b) synergism between innate and adaptive immune response; (c) tumor-immune system interactions within the tumor microenvironment.

Animals↗

Molecular detection of circulating tumor cells is an independent prognostic factor in patients with high-risk cutaneous melanoma.

Detection of circulating tumor cells (CTCs) might improve current staging procedures by identifying a subgroup of patients with minimal residual disease and thus a higher risk of disease recurrence. Forty patients with > or =2-mm-thick cutaneous melanoma with or without lymph node metastasis were enrolled. After standard radical surgery and adjuvant therapy in case of lymph node metastasis, patients were followed up with routine physical and radiologic assessments as well as serial PCR-based analysis of CTCs using 2 melanoma markers (tyrosinase and Melan-A/Mart-1). After a median follow-up of 30 months, 18 patients had disease recurrence and 28 were PCR-positive before the disease became clinically evident. The sensitivity of the molecular test was 83%. Median time to PCR positivity and median PCR-to-relapse time were 12 and 8 months, respectively. At multivariate analysis, PCR positivity was an independent predictor of disease recurrence (hazard ratio=2.06, 95% CI 1.07-3.35; p=0.03). Among high-risk melanoma patients, serial PCR-based analysis of CTCs can identify a subgroup at higher risk of disease recurrence, with clinically significant advance. Therefore, CTC detection might be employed for the selection of patients for adjuvant treatment and during follow-up for early indication of therapeutic failure.

Adolescent↗

True versus mild hyperthermia during isolated hepatic perfusion: effects on melphalan pharmacokinetics and liver function.

Hyperthermic antiblastic isolated hepatic perfusion (IHP) with melphalan has been recently proposed as an alternative therapeutic option for patients with unresectable liver tumors. Although melphalan-heat antiblastic synergism is at a maximum at temperatures higher than 41 degrees C, IHP has so far been performed in humans at lower temperatures. In this experimental work, we compared IHP under mild versus true hyperthermic conditions in terms of drug pharmacokinetics and liver function. Ten pigs were submitted to IHP with melphalan 1.5 mg/kg at a mean temperature of 40 degrees C (group A, n = 5) or 42 degrees C (group B, n = 5). After a 60-minute perfusion, a 15-minute washout was performed. Perfusate-to-plasma leakage was monitored using scintigraphy. Throughout perfusion, samples from the systemic blood, perfusate, and liver parenchyma were obtained to measure melphalan concentrations. Liver function was assessed using standard blood tests and the indocyanine green-based test. No deaths related to the IHP procedure were recorded. All animals had transient liver function impairment, with all liver function test results returning to normal within the observation period. At histologic examination, liver damage was similar under both hyperthermic conditions. Melphalan levels in the perfusate were not significantly different in the two study groups (the mean perfusate/plasma area under the curve from 0 to 60 minutes ratios were 463 and 501, respectively). These results correlated well with those obtained using the scintigraphic method. Liver drug concentrations remained unchanged after true hyperthermia IHP. Under true hyperthermic conditions, neither an increase in liver parenchyma toxicity nor changes in melphalan pharmacokinetics were observed. These findings support the use of true hyperthermia in the clinical setting to exploit fully the antitumor synergism between melphalan and heat.

Animals↗

DNA array-based gene profiling in tumor immunology.

Recent advances in tumor immunology have fostered the clinical implementation of different immunotherapy modalities. However, the alternate success of such regimens underscores the fact that the molecular mechanisms underlying tumor immune rejection are still poorly understood. Given the complexity of the immune system network and the multidimensionality of tumor-host interactions, the comprehension of tumor immunology might greatly benefit from high-throughput DNA array analysis, which can portray the molecular kinetics of immune response on a genome-wide scale, thus accelerating the accumulation of knowledge and ultimately catalyzing the development of new hypotheses in cell biology. Although in its infancy, the implementation of DNA array technology in tumor immunology studies has already provided investigators with novel data and intriguing hypotheses on the cascade of molecular events leading to an effective immune response against cancer. Although the principles of DNA array-based gene profiling techniques have become common knowledge, the need for mastering this technique to produce meaningful data and correctly interpret this enormous output of information is critical and represents a tremendous challenge for investigators. In the present work, we summarize the main technical features and critical issues characterizing this powerful laboratory tool and review its applications in the fascinating field of cancer immunogenomics.

Base Sequence↗

Hyperthermic intraperitoneal intraoperative chemotherapy after cytoreductive surgery for the treatment of abdominal sarcomatosis: clinical outcome and prognostic factors in 60 consecutive patients.

BACKGROUND: Abdominal sarcomatosis is a rare nosologic entity with a poor prognosis. After a Phase I study on cytoreductive surgery combined with hyperthermic intraperitoneal intraoperative chemotherapy (HIIC), the authors reported the results of the treatment of 60 patients using this novel multimodal approach. METHODS: Twenty-nine patients had multifocal primary disease and 31 patients had recurrent abdominal sarcoma. Tumor histology was represented by visceral (n = 26 [43%]) and retroperitoneal (n = 34 [57%]) sarcoma. All patients underwent cytoreductive surgery (with no or minimal residual disease) and 90-minute HIIC with doxorubicin (15.25 mg/L of perfusate) and cisplatin (43 mg/L). The clinical outcome and the prognostic value of 11 clinicopathologic variables were analyzed. RESULTS: No postoperative deaths occurred. The morbidity rate was 33% and the moderate to severe locoregional toxicity rate was 15%. The median time to local disease progression and the median overall survival were 22 months and 34 months, respectively. Using multivariate analysis, histologic grading and completeness of surgical cytoreduction predicted patient prognosis, indicating that both local progression-free and overall survival were affected significantly by tumor aggressiveness and local disease control. CONCLUSIONS: Although these results were encouraging, there was no definitive conclusion reached regarding the therapeutic activity of this locoregional treatment. In addition, the toxicity rate was substantial. In the absence of effective systemic agents, the therapeutic potential of cytoreductive surgery plus HIIC should be explored further in comparative trials.

Abdominal Neoplasms↗

Reduction in PSA messenger-RNA expression and clinical recurrence in patients with prostatic cancer undergoing neoadjuvant therapy before radical prostatectomy.

BACKGROUND: We assessed the incidence of micro-metastases at surgical margins (SM) and pelvic lymph nodes (LN) in patients submitted to radical retropubic prostatectomy (RP) after neoadjuvant therapy (NT) or to RP alone. We compared traditional staging to molecular detection of PSA using Taqman-based quantitative real-time PCR (qrt-PCR) never used before for this purpose. METHODS: 29 patients were assigned to NT plus RP (arm A) or RP alone (arm B). Pelvic LN were dissected for qrt-PCR analysis, together with right and left lateral SM. RESULTS: 64,3% patients of arm B and 26.6% of arm A had evidence of PSA mRNA expression in LN and/or SM. 17,2% patients, all of arm B, had biochemical recurrence. CONCLUSIONS: Qrt-PCR may be more sensitive, compared to conventional histology, in identifying presence of viable prostate carcinoma cells in SM and LN. Gene expression of PSA in surgical periprostatic samples might be considered as a novel and reliable indicator of minimal residual disease after NT.

Journal Article↗

The multifaceted relationship between IL-10 and adaptive immunity: putting together the pieces of a puzzle.

Interleukin-10 (IL-10) is a pleiotropic cytokine that modulates the function of several adaptive immunity-related cells. Although generally considered an immunosuppressive molecule, IL-10 possesses immunostimulatory properties in several in vitro and in vivo models. These very different outcomes are believed to depend upon experimental conditions, the dominant immune effector mediating a given immune response, the timing of IL-10 production/administration, and IL-10 dose and/or location of expression. In the present work, we review the current knowledge regarding IL-10 activity on adaptive immunity related cells, emphasize new insights on IL-10 molecular/cellular targets, and summarize the available data on the relationship between IL-10 and some pathological conditions (e.g. infectious diseases, autoimmunity, allergy, cancer and transplantation) involving adaptive immunity.

Animals↗

Part I: Vaccines for solid tumours.

Active specific immunotherapy holds great potential in the search for new therapeutic approaches for patients with cancer. Much preclinical and clinical evidence has shown that the immune system can be polarised against malignant cells by several vaccination strategies. Although no anticancer vaccine can be recommended outside clinical trials at present, tumour response and immunological findings in animals and humans should prompt researchers to investigate further the potential of this biotherapy. We summarise strategies for cancer vaccines so far implemented in the clinical setting, report the results of more than 200 clinical trials published over the past two decades, and discuss insights into preclinical tumour immunology that might aid the design of the next generation of cancer vaccines.

Antigens, Neoplasm↗

Part II: Vaccines for haematological malignant disorders.

The search for new therapeutic approaches to haematological malignant disease involves exploitation of the antitumour potential of adaptive immunity-the most specific killing system against cancer currently known. Here, we summarise immunological strategies behind active specific immunotherapy, and describe the clinical and immunological results from trials published to date. Available data in humans support the hypothesis that various vaccination regimens can polarise adaptive immunity towards effective control of cancer-cell growth. However, the exploratory nature of clinical studies done thus far does not allow any cancer vaccine to be used as standard treatment for haematological malignant disorders. Because the cause of disease recurrence is the presence of minimal residual disease after conventional treatments, the adjuvant setting might be the most appropriate therapeutic strategy for active specific immunotherapy, when the immunosuppressive effects of bulky disease are virtually absent and when the effector-target ratio is favourable. In the near future, completion of randomised phase III trials as well as clinical implementation of the most recent insights into tumour immunology that aim to overcome immune tolerance towards malignant cells should allow investigators to define the actual role of vaccines in the management of haematological tumours.

Antigens, Neoplasm↗