Intravenous and isolated limb perfusion delivery of wild type and a tumor-selective replicating mutant vaccinia virus in nonhuman primates

In this study we examine the safety, feasibility, and biodistribution of a tumor-selective mutant vaccinia (vvDD) and wild-type WR (vF13) vaccinia after delivery via intradermal or intravenous infection or isolated limb perfusion (ILP) in rhesus macaques. By intradermal inoculation, 10(6) PFU of vvDD caused a minimal skin reaction whereas vF13 caused marked erythema and necrosis with a peak indurated area of 108 cm2. By intravenous delivery, vvDD caused no clinical symptoms of viremia and no viral recovery from tissues, serum, saliva, urine, or feces. In contrast, vF13 caused symptoms of lethargy, anorexia, fever, and signs of viremia. Delivery of vF13 via ILP resulted in numerous cutaneous pox lesions localized solely to the perfused limb with high viral recovery in the perfused skin and muscle. ILP with vvDD resulted in no visible pox lesions and no clinical signs or symptoms of viremia. No long-term toxicity was identified after ILP with 10(9) PFU of vvDD, and no virus was recovered from any tissue, serum, saliva, urine, or fecal sample. These results suggest that vvDD appears to be safe in primates, and thus vvDD should be further investigated for clinical trial in human cancer patients.

MHC–peptide specificity and T-cell epitope mapping: where immunotherapy starts

The evaluation and characterization of epitope-specific human leukocyte antigen (HLA)-restricted memory T-cell reactivity is an important step for the development of preventive vaccines and peptide-based immunotherapies for viral and tumor diseases. The past decade has witnessed the use of HLA-restricted peptides as tools to activate strong immune responses of naïve or memory T cells specifically. This has fuelled an active search for methodological approaches focusing on HLA and peptide associations. Here, we outline new perspective on the emerging opportunity of evaluating HLA and peptide restriction by using novel approaches, such as quantitative real-time PCR, that can identify epitope specificities that are potentially useful in clinical settings.

The prognostic value of circulating tumor cells in patients with melanoma: a systematic review and meta-analysis

BACKGROUND

The detection of circulating tumor cells (CTC) in patients with melanoma represents an appealing prognostic tool, but no consensus exists on this topic. We aimed to comprehensively and quantitatively summarize the evidence for the use of CTC to predict patients' clinical outcome.

METHODS

Fifty-three studies enrolling 5,433 patients were reviewed. Correlation of CTC status with tumor-node-metastasis disease stage and patients' overall (OS) and progression-free (PFS) survival was assessed by means of association statistics and meta-analysis, respectively.

RESULTS

CTC status correlated with both tumor-node-metastasis stage (stage I, 32%; stage II, 41.7%; stage III, 41.1%; stage IV, 47.4%; P(trend) < 0.0001) and survival (OS: hazard ratio, 2.42; 95% confidence interval, 1.7-3.45, P < 0.0001; PFS: hazard ratio, 2.45; 95% confidence interval, 1.78-3.38; P < 0.0001). However, statistical heterogeneity was significant for both OS and PFS, likely underscoring the wide variability in study design. Furthermore, CTC positivity rates in early stages were higher and in the metastatic setting were lower than expected, which indicates an unsatisfactory accuracy of currently available CTC detection assays.

CONCLUSIONS

Our findings suggest that CTC might have a clinically valuable prognostic power in patients with melanoma. However, the heterogeneity of the studies thus far published warrants caution not to overestimate the favorable results of pooled data.

Support Vector Machine Learning Model for the Prediction of Sentinel Node Status in Patients With Cutaneous Melanoma

BACKGROUND

Currently, approximately 80% of melanoma patients undergoing sentinel node biopsy (SNB) have negative sentinel lymph nodes (SLNs), and no prediction system is reliable enough to be implemented in the clinical setting to reduce the number of SNB procedures. In this study, the predictive power of support vector machine (SVM)-based statistical analysis was tested.

METHODS

The clinical records of 246 patients who underwent SNB at our institution were used for this analysis. The following clinicopathologic variables were considered: the patient's age and sex and the tumor's histological subtype, Breslow thickness, Clark level, ulceration, mitotic index, lymphocyte infiltration, regression, angiolymphatic invasion, microsatellitosis, and growth phase. The results of SVM-based prediction of SLN status were compared with those achieved with logistic regression.

RESULTS

The SLN positivity rate was 22% (52 of 234). When the accuracy was > or = 80%, the negative predictive value, positive predictive value, specificity, and sensitivity were 98%, 54%, 94%, and 77% and 82%, 41%, 69%, and 93% by using SVM and logistic regression, respectively. Moreover, SVM and logistic regression were associated with a diagnostic error and an SNB percentage reduction of (1) 1% and 60% and (2) 15% and 73%, respectively.

CONCLUSIONS

The results from this pilot study suggest that SVM-based prediction of SLN status might be evaluated as a prognostic method to avoid the SNB procedure in 60% of patients currently eligible, with a very low error rate. If validated in larger series, this strategy would lead to obvious advantages in terms of both patient quality of life and costs for the health care system.

Circulating tumor cells: the 'leukemic phase' of solid cancers

It is well known that malignant cells circulate in the bloodstream of patients with solid tumors. However, the biological significance of circulating tumor cells (CTCs) and the clinical relevance of their detection are still debated. Besides technical issues regarding CTC-detection methods, discontinuous shedding of CTCs from established cancer deposits, genomic instability and metastatic inefficiency might underlie the conflicting results currently available. Nevertheless, technological advances and recent clinical findings are prompting researchers to dissect CTC biology further. Here, we review these recent findings, and discuss the prospects for the identification and molecular characterization of the CTC subset that is responsible for metastasis development. This would provide a formidable tool for prognosis evaluation, anticancer-drug development and, ultimately, cancer-therapy personalization.

Adult soft tissue sarcomas: Conventional therapies and molecularly targeted approaches

The therapeutic approach to soft tissue sarcomas (STS) has evolved over the past two decades based on the results from randomized controlled trials, which are guiding physicians in the treatment decision-making process. Despite significant improvements in the control of local disease, a significant number of patients ultimately die of recurrent/metastatic disease following radical surgery due to a lack of effective adjuvant treatments. In addition, the characteristic chemoresistance of STS has compromised the therapeutic value of conventional antineoplastic agents in cases of unresectable advanced/metastatic disease. Therefore, novel therapeutic strategies are urgently needed to improve the prognosis of patients with STS. Recent advances in STS biology are paving the way to the development of molecularly targeted therapeutic strategies, the efficacy of which relies not only on the knowledge of the molecular mechanisms underlying cancer development/progression but also on the personalization of the therapeutic regimen according to the molecular features of individual tumours. In this work, we review the state-of-the-art of conventional treatments for STS and summarize the most promising findings in the development of molecularly targeted therapeutic approaches.

The impact of lymphoscintigraphy technique on the outcome of sentinel node biopsy in 1,313 patients with cutaneous melanoma: an Italian Multicentric Study (SOLISM-IMI)

An observational multicentric Italian trial on sentinel node biopsy (SNB) in melanoma patients was performed to diffuse a common SNB protocol nationwide (Italy). We report herein the results of this trial. The influence of some technical aspects on the outcome of SNB was also investigated, because a certain degree of variability was accepted in performing lymphoscintigraphy.

METHODS

From January 2000 to December 2002, 1,313 consecutive patients with primary cutaneous melanoma (Breslow thickness, >1.0 mm or <1.0 mm but with ulceration, Clark level IV-V, presence of regression) were enrolled by 23 centers. One half to 1 mL of 99mTc-labeled human albumin colloid, at a suggested dosage of 5-15 or 30-70 MBq, was injected intradermally, closely around the scar, the same day or the day before SNB. Intraoperatively, Patent blue was associated when a definitive wide excision of the primary was required. A positive sentinel node (SN) was defined when containing melanoma cells detected by either hematoxylin-eosin or immunohistochemistry (S100 and HMB45 antibodies). All patients underwent regular follow-up. False-negative cases were considered when lymph node metastases occurred in the same lymphatic basin of SN biopsy (SNB) during follow-up. A quality control program has been performed for the surgical procedure and for the histologic diagnosis.

RESULTS

The SN identification rate was 99.3%. The axilla was the site of the SN in 52.5% of the cases. The mean number of SNs was 2.0 (range, 1-17) and only 1 node was removed in 45.4%. The positivity and false-negative rates were 16.9% and 14.7%, respectively (median follow-up, 31 mo). On multivariate analysis (logistic and linear regression) only the number of peritumor injections was inversely associated with the number of excised SNs (P = 0.002), whereas none of the technical variables showed an independent impact on SN status when Breslow thickness was included as a control variable.

CONCLUSION

The number of peritumor injections seems to influence the outcome of lymphoscintigrapy in melanoma patients undergoing SNB. If these results are confirmed in a controlled trial, 3 injections at least should be recommended.

RNA interference: ready to silence cancer?

RNA interference (RNAi) is considered the most promising functional genomics tool recently developed. As in other medical fields, this biotechnology might revolutionize the approach to dissecting the biology of cancer, ultimately speeding up the discovery pace of novel targets suitable for molecularly tailored antitumor therapies. In addition, preclinical results suggest that RNAi itself might be used as a therapeutic weapon. With the aim of illustrating not only the potentials but also the current limitations of RNAi as a tool in the fight against cancer, here we summarize the physiology of RNAi, discuss the main technical issues of RNAi-based gene silencing, and review some of the most interesting preclinical results obtained so far with its implementation in the field of oncology.

Targeted therapy for colorectal cancer: mapping the way

In spite of the significant advances in conventional therapeutic approaches to colorectal cancer (CRC), most patients ultimately die of their disease. Dissecting the molecular mechanisms underlying CRC progression will not only accelerate the development of novel cancer-selective drugs but will also enable the therapeutic regimen to be personalized according to the molecular features of individual patients and tumors. Here, we report on the novel insights into CRC biology that are paving the way to the development of molecular therapies and summarize the results from recent clinical trials demonstrating that agents targeting tumor-specific molecular derangements can significantly improve the therapeutic efficacy of conventional chemotherapy. Only a broader clinical implementation of these concepts will provide patients with CRC the best chance of a cure.

Interleukin-10 and the immune response against cancer: a counterpoint

Although interleukin-10 (IL-10) is commonly regarded as an anti-inflammatory, immunosuppressive cytokine that favors tumor escape from immune surveillance, a wealth of evidence is accumulating that IL-10 also possesses some immunostimulating properties. In fact, IL-10 has the pleiotropic ability of influencing positively and negatively the function of innate and adaptive immunity in different experimental models, which makes it questionable to merely categorize this cytokine as a target of anti-immune escape therapeutic strategies or rather, as an immunological adjuvant in the fight against cancer. Here, we review available data about the immunostimulating anticancer properties of IL-10, and in particular, we focus on the hypothesis that in contrast to what occurs in secondary lymphoid organs, IL-10 overexpression within the tumor microenvironment may catalyze cancer immune rejection.

Colorectal liver metastasis: towards the integration of conventional and molecularly targeted therapeutic approaches

Radical surgery currently represents the only treatment with curative potential for patients with colorectal cancer (CRC) liver metastases. Unfortunately, only a minority of cases is eligible for hepatic resection and many patients still develop recurrent disease, which underscores the need for more effective adjuvant treatments. In case of unresectable disease, locoregional therapeutic strategies can obtain significant tumor regression/local disease control rates, but there is no definitive evidence of their effect on patients' survival. In regards to systemic chemotherapy, the conduction of randomized controlled trials has led to a substantial progress in terms of both tumor response and survival rates. Despite these results, most patients ultimately die of their disease due to hepatic and/or extra-hepatic cancer progression. Therefore, novel therapeutic strategies are urgently needed to improve the prognosis of patients with metastatic CRC. The elucidation of CRC biology is paving the way to the development of molecularly targeted strategies, and results from controlled clinical trials have already demonstrated that some agents targeting tumor-specific molecules can significantly improve the therapeutic efficacy of conventional antineoplastic drugs. The dissection of the molecular mechanisms of CRC metastatization and tumor/host interactions will not only accelerate the development of more effective and less toxic anticancer strategies but also will allow for the personalization of the therapeutic regimen according to the molecular features of individual patients and their tumors. Only the broader clinical implementation of these novel molecular oncology findings and the optimal integration of conventional and molecularly targeted therapeutic approaches will enable clinicians to provide patients with a better chance of cure.

Cancer vaccines: the challenge of developing an ideal tumor killing system

Despite the evidence that the immune system plays a significant role in controlling tumor growth in natural conditions and in response to therapeutic vaccination, cancer cells can survive their attack as the disease progresses and no vaccination regimen should be currently proposed to patients outside experimental clinical trials. Clinical results show that the immune system can be actively polarized against malignant cells by means of a variety of vaccination strategies, 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 put at work and used as endogenous weapons against malignant cells. Consequently, the main challenge of tumor immunologists appears to lie on the ability of reproducing those conditions in a larger set of patients. The complexity of the immune network and the still enigmatic host-tumor interactions make these tasks at the same time challenging and fascinating. Recent tumor immunology findings are giving new impetus to the development of more effective vaccination strategies and might revolutionize the way of designing the next generation of cancer vaccines. In the near future, the implementation of these insights in the clinical setting and the completion/conduction of comparative randomized phase III trials will allow oncologists to define the actual role of cancer vaccines in the fight against malignancy.

The challenge of implementing high-throughput technologies in clinical trials

One of the pillars on which modern translational medicine is founded lies in the search/choice of appropriate biomarkers.

[Trends in colorectal cancer vaccination]

Anticancer vaccination is a promising therapeutic approach for colorectal cancer patients. The immune system can be polarized against malignant cells by means of several active specific immunotherapeutic regimens. Although no vaccination regimens can be recommended outside clinical trials, tumor response and recent immunological findings prompt researchers to explore further the antitumor potential of such bio-therapy in order to achieve a successful tumor immune rejection.

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.

Hyperthermic Isolated Perfusion With Low-Dose Tumor Necrosis Factor α and Doxorubicin for the Treatment of Limb-Threatening Soft Tissue Sarcomas

BACKGROUND

Tumor necrosis factor (TNF)-alpha-based hyperthermic isolated limb perfusion (HILP) is one of the most active available approaches for locally advanced soft tissue sarcomas (STS) of the limbs. The aim of this study was to investigate the anticancer activity of a novel drug regimen including doxorubicin (DXR) and low-dose TNF-alpha.

METHODS

HILP with low-dose TNF-alpha (1 mg) and DXR (8.5 mg/L of limb volume) was given to 21 patients with limb-threatening STS: 14 had primary and 7 had recurrent STS, most of which were high grade (grade 1, n = 3; grade 2, n = 6; grade 3, n = 12). Resection of the tumor remnant was performed 6 to 8 weeks after HILP. TNF-alpha concentrations in plasma and perfusate were measured throughout perfusion.

RESULTS

A major tumor response was observed at histology and clinical evaluation in 90% and 62% of patients, respectively. After a median follow-up of 30 months, limb salvage and local disease control were achieved in 71% and 81% of cases, respectively. Fourteen patients had moderate regional toxicity, which was resolved in all cases. One patient had severe limb toxicity, which did not require amputation. Systemic side effects were minimal, and there were no postoperative deaths. The perfusate/plasma area under the curve ratio for TNF-alpha was 56.

CONCLUSIONS

HILP with low-dose TNF-alpha and DXR seems to be an active neoadjuvant drug regimen against limb-threatening STS. This therapeutic approach can achieve high limb-sparing surgery rates with acceptable local and negligible systemic toxicity.

IL-10 stimulatory effects on human NK cells explored by gene profile analysis

The molecular mechanisms underlying the increase of natural killer (NK) cell anticancer activity mediated by interleukin (IL)-10 have not been elucidated. The aim of this study was to identify potential molecular mediators of IL-10 stimulatory effects by exploring the NK cell gene display induced by this cytokine. Gene profile was determined by high-throughput cDNA microarray and quantitative real-time PCR. In vitro, NK cells resting or conditioned with IL-10 were tested for cytotoxicity, migration and proliferation. IL-10 enhanced mRNA levels of cell activation/cytotoxicity-related genes (eg secretogranin, TIA-1, HMG-1, interferon-inducible genes) not upregulated by IL-2. In line with these findings, IL-10 increased NK cell in vitro cytotoxicity against Daudi cells. Unlike IL-2, IL-10 did not show any significant effect on NK cell in vitro proliferation and migration. However, gene profile analysis showed that IL-10 increased the expression of cell migration-related genes (eg L-selectin, vascular endothelium growth factor receptor-1, plasminogen activator, tissue; formyl peptide receptor, lipoxin A4 receptor), which might support a stimulatory effect not evident with the in vitro functional assay. Overall, gene profiling allowed us to formulate new hypotheses regarding the molecular pathways underlying the stimulatory effects of IL-10 on NK cells, supporting further investigation aimed at defining its role in cancer immune rejection.

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.

Hyperthermic isolated liver perfusion for unresectable liver cancers: pilot study

Isolated hepatic perfusion (IHP) is a recently reconsidered locoregional approach for unresectable primary or metastatic cancer and encouraging results have been achieved from its clinical application. Ten patients underwent hyperthermic IHP with melphalan. There was no intraoperative mortality. In the postoperative period two patients died due to multi-organ failure. Four patients had significant but transient hepatic toxicity. In 8 assessable patients, the overall response rate was 63%. We observed objective tumor regression in a significant percentage of patients refractory to standard treatments. Locoregional toxicity was significant, which underscores the need for a more accurate preoperative evaluation of hepatic function.

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.

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.

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.

Colorectal cancer vaccines: principles, results, and perspectives

In the search for novel therapeutic approaches to treat patients with colorectal carcinoma, anticancer vaccination holds promise. A large body of preclinical and clinical evidence has demonstrated that the immune system can be polarized against malignant cells by means of several active specific immunotherapy strategies. Although no vaccination regimen can be currently recommended outside clinical trials, tumor response and immunologic findings observed in animal models and humans prompt researchers to explore further the antitumor potential of such biotherapy in an effort to reproduce in a larger set of patients the cascade of molecular events that characterizes the successful tumor immune rejection currently observed in a minority of vaccinated subjects. In this work, we summarize the principles and the main results of cancer vaccine strategies so far implemented for the treatment of patients with colorectal carcinoma. We also discuss the most recent preclinical tumor immunology insights that might change the way to design the next generation of cancer vaccines, hopefully improving the effectiveness of such a biotherapeutic approach.

RNA interference: learning gene knock-down from cell physiology

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.

Hypoxic antiblastic stop-flow perfusion: clinical outcome and pharmacokinetic findings

Stop-flow perfusion (SFP) is a recently implemented locoregional treatment based on the vascular isolation of the tumor bearing body district through a radiointerventistic technique. SFP is currently under investigation as a palliative therapeutic option for patients with locally advanced tumors. This paper reports on the results of our prospective study of limb and pelvic SFP. Thirty-seven patients were treated with SFP. No postoperative deaths occurred. Locoregional and systemic toxicity were observed after 22 and 31 treatments, respectively; complete and partial response after 3 (6%) and 24 (51%) SFPs, respectively. The pharmacokinetic study showed that pelvic SFP was associated with a leakage rate higher than femoral SFP (38% vs 28%). In conclusion, SFP is a feasible procedure. Toxicity and tumor response rates strictly depend upon drug leakage control.

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.

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.

Melanoma - what is new in sentinel node biopsy and locoregional treatments in 2003? Report of a workshop at the Third Research Meeting on Melanoma, Milan, Italy, May 2003

This paper reports on the scientific session on sentinel node biopsy, surgery and locoregional treatments that took place during the Third Research Meeting on Melanoma, Milan, Italy, held in May 2003. It provides an overview of contributions presented at the meeting grouped according to subject - ultrasound scanning, sentinel node biopsy, mini-invasive surgery and stop-flow limb perfusion. The main comments made by the respective rapporteurs are also summarized.

Hypoxic antiblastic stop-flow limb perfusion: clinical outcome and pharmacokinetic findings of a novel treatment for in transit melanoma metastases

Hypoxic antiblastic stop-flow perfusion (SFP) has recently been proposed as a therapeutic option for patients with locally advanced tumors. We report on the clinical and pharmacological results of our prospective study of limb SFP for the treatment of in transit melanoma metastases. Twenty-three patients with limb-sited melanoma metastases were treated with melphalan (10 mg/l) based pelvic (n=11, group A) or femoral (n=12, group B) SFP under hypoxic conditions. Systemic and locoregional toxicity, tumor response rate, and local progression-free survival were analyzed. Melphalan concentrations were measured in the perfusate and systemic circulation during SFP, and after 30-min hemofiltration. Perfusate-to-plasma leakage was assessed using a scintigraphic method. No postoperative deaths occurred. Mild locoregional toxicity was observed in 5 patients (18%), and systemic toxicity was mild to severe in 8 patients (30%), the incidence being higher in group A. Tumor response rate (complete + partial response) and time to local disease progression were significantly different in group A and B (9% vs 58% and 7 vs 13 months, respectively). The pharmacokinetic study showed that pelvic SFP was associated with a higher leakage rate and a lower area under the curve ratio than femoral SFP (44% vs 31% and 5.6 vs 9.8, respectively). Limb SFP is a feasible and relatively simple procedure. Toxicity and tumor response rates strictly depend upon drug leakage control. Further efforts should be made to exploit the potential anti-tumor activity of this novel locoregional drug delivery system.

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.

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.

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.

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.

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.

Hyperthermic Isolated Limb Perfusion With Low-Dose Tumor Necrosis Factor-α and Melphalan for Bulky In-Transit Melanoma Metastases

BACKGROUND

Melphalan (L-PAM) hyperthermic isolated limb perfusion (HILP) is currently considered the standard treatment for patients with in-transit metastases from cutaneous melanoma. We here report on the results of L-PAM and low-dose tumor necrosis factor (TNF)alpha HILP in patients with bulky disease.

METHODS

Twenty patients underwent TNFalpha (1 mg) and L-PAM (10 mg/L) HILP. Perfusion was performed for 90 minutes, and systemic leakage was strictly monitored. Locoregional toxicity was evaluated according to Wieberdink's criteria, whereas tumor response was evaluated with physical examination and ultrasound scan with or without fine-needle aspiration of any suspected recurrence.

RESULTS

In all cases, systemic leakage was <5%. No postoperative deaths occurred, and locoregional toxicity was mild (grade 1 or 2) in 95% of patients. A complete tumor response was obtained in 14 patients (70%), and partial responses were obtained in 5 patients (25%). After a median follow-up of 18 months, six patients are alive and disease free, seven are alive with local or distant recurrence or both, and seven have died of disease.

CONCLUSIONS

Low-dose TNFalpha HILP can achieve tumor responses comparable with those reported with higher doses of cytokine. Moreover, this drug regimen is associated with acceptable local toxicity, carries a smaller risk of systemic toxicity, and incurs lower costs.

Dissecting tumor responsiveness to immunotherapy: the experience of peptide-based melanoma vaccines

Recent years have witnessed important breakthroughs in our understanding of tumor immunology. A variety of immunotherapeutic strategies has shown that immune manipulation can induce the regression of established cancer in humans. The identification of the genes encoding tumor-associated antigens (TAA) and the development of means for immunizing against these antigens have opened new avenues for the development of an effective anticancer immunotherapy. However, an efficient immune response against tumor requires an intricate cross-talk between cancer and immune system cells, which is still poorly understood. Only when the molecular basis underlying tumor susceptibility to an immune response is deciphered could new therapeutic strategies be designed to fit biologically defined mechanisms of cancer immune rejection. In this article, we address some of the critical issues that have been identified in cancer immunotherapy, in part from our own studies on immune therapies in melanoma patients treated with peptide-based vaccination regimens. This is not meant to be a comprehensive overview of the immunological phenomena accompanying cancer patient vaccination but rather emphasizes some emergent findings, puzzling controversies and unanswered questions that characterize this complex field of oncology. In addition to reviewing the main immunological concepts underlying peptide-based vaccination, we also review the available data regarding naturally occurring and therapeutically induced anticancer immune response, both at the peripheral and intratumoral level. The hypothesized role of innate immunity in predetermining tumor responsiveness to immunotherapeutic manipulation is also discussed.

Ex vivo screening for immunodominant viral epitopes by quantitative real time polymerase chain reaction (qRT-PCR)

The identification and characterization of viral epitopes across the Human Leukocyte Antigen (HLA) polymorphism is critical for the development of actives-specific or adoptive immunotherapy of virally-mediated diseases. This work investigates whether cytokine mRNA transcripts could be used to identify epitope-specific HLA-restricted memory T lymphocytes reactivity directly in fresh peripheral blood mononuclear cells (PBMCs) from viral-seropositive individuals in response to ex vivo antigen recall. PBMCs from HLA-A*0201 healthy donors, seropositive for Cytomegalovirus (CMV) and Influenza (Flu), were exposed for different periods and at different cell concentrations to the HLA-A*0201-restricted viral FluM158-66 and CMVpp65495-503 peptides. Quantitative real time PCR (qRT-PCR) was employed to evaluate memory T lymphocyte immune reactivation by measuring the production of mRNA encoding four cytokines: Interferon-gamma (IFN-gamma), Interleukin-2 (IL-2), Interleukin-4 (IL-4), and Interleukin-10 (IL-10). We could characterize cytokine expression kinetics that illustrated how cytokine mRNA levels could be used as ex vivo indicators of T cell reactivity. Particularly, IFN-gamma mRNA transcripts could be consistently detected within 3 to 12 hours of short-term stimulation in levels sufficient to screen for HLA-restricted viral immune responses in seropositive subjects. This strategy will enhance the efficiency of the identification of viral epitopes independently of the individual HLA phenotype and could be used to follow the intensity of immune responses during disease progression or in response to in vivo antigen-specific immunization.

The matrix protein pp65(341-350): a peptide that induces ex vivo stimulation and in vitro expansion of CMV-specific CD8+ T cells in subjects bearing either HLA-A*2402 or A*0101 allele

BACKGROUND

The stimulation of PBMNCs with HLA Class I restricted synthetic peptides derived from CMV phosphorylated matrix protein 65 (pp65) evokes CMV-specific cytotoxic T lymphocyte (CTL) activity, a necessary condition for initiating adoptive immunotherapy against CMV-related diseases in immune-compromised patients. It was previously demonstrated that the CMV decamer (10-mer) peptide pp65(341-350), QYDPVAALFF, was able to induce CMV-specific CTLs in HLA-A*2402 CMV-seropositive individuals.

STUDY DESIGN AND METHOD

We investigated the ability of the peptide pp65(341-350) to reactivate memory CD8+ T cells in CMV-seropositive subjects bearing either the HLA-A24 or A1 allele. CTL responses were measured by IFN-gamma mRNA expression and IFN-gamma protein production as well as cytotoxic activity.

RESULTS

In this study it was found that peptide pp65(341-350) induced a specific reactivation of memory CD8+ T cells from CMV-seropositive donors expressing either HLA-A*2402 and/or HLA-A*0101. Moreover, a pp65(341-350)-specific selection and expansion using PBMNCs of CMV-seropositive donors bearing both HLA-A*2402 and HLA-A*0101 alleles produced cytotoxic CTLs to both HLA-A24 and A1 peptide-pulsed and autologous CMV-infected target cells.

CONCLUSION

The results demonstrate that pp65(341-350) induced a specific CTL activity at both molecular and protein levels and that the peptide is specifically processed, presented, and recognized by subjects bearing HLA-A*2402 and/or A*0101. These findings suggest that it may be possible to use this single immune dominant peptide to induce and expand CMV-reactive CTLs for the treatment of individuals with both HLA-A24 and A1 types.

TNF-based limb perfusion for cutaneous melanoma in transit metastases: suggestions for modification of the perfusional schedule

Isolated limb perfusion (ILP) is currently considered the standard treatment for melanoma patients with extensive in-transit disease, and L-PAM, combined or not with TNF, represents the most active drug. We here report on our clinical experience with TNF-based limb perfusion. Thirty-seven stage III patients underwent TNF-based limb perfusion, 22 with bulky disease, 15 with recurrences after perfusion with L-PAM. Ten patients were enrolled in a phase I-II study and treated with escalating doses of TNF (0.5-3 mg). The impact of disease burden, temperature, perfusion duration was assessed on tumor response. No postoperative death was observed. No significant systemic toxicity was recorded. Locoregional toxicity was G5 in one patient, G3 in 2, G2 in 9 and G1 in 25. Twenty-four (66%) patients had complete response, 11 (31%) partial and 1 (3%) no change. After a median follow-up of 20 months 14 (38%) patients are NED, 10 (27%) are AWD and 13 (35%) DOD. No significant statistical difference for tumor response were seen for disease burden, ILP temperatures and duration. Our results showed that it is possible to modify the perfusion schedule, without compromising the response rate but with lower cost and toxicity.

Treatment options for liver metastases from colorectal cancer

The liver is the most common site of distant metastasis from colorectal cancer. About one-fourth of patients with liver metastases from colorectal cancer have no other sites of metastasis. Surgical resection of colorectal cancer liver metastases can result in a 24%-38% five-year survival. However, only a minority of patients are candidates for resection and no adjuvant treatment has been demonstrated to be effective in increasing the survival rate following radical surgery. For unresectable disease, several treatments have been tested in the clinical setting, although none of them can be currently considered a standard approach. Systemic chemotherapy is not generally considered a treatment for cure, although newer regimens appear to improve median survival. Locoregional therapies such hepatic intra-arterial chemotherapy and isolated hepatic perfusion may be offered to patients with unresectable liver metastases in the absence of extra-hepatic disease. However, the efficacy of these treatments is still being determined. Both systemic and locoregional chemotherapy might be useful in the neoadjuvant setting to increase the resectability of liver metastases initially not amenable to surgical resection.

Pharmacokinetics of intraperitoneal cisplatin and doxorubicin

Intraperitoneal chemotherapy, mainly when performed during HIIC after cytoreductive surgery, is considered potentially curative for the treatment of solid tumors with spread to the peritoneal surface. When selecting antiblastic agents to be administered intraperitoneally, it is important to bear in mind that a low lipophility and a high molecular weight are the ideal drug characteristics. Drugs with these features allow a favorable ratio to be achieved between peritoneal and plasma concentrations, due to the reduced tendency to diffuse through the plasma-peritoneal barrier, even after extensive removal of the peritoneum. Moreover, a low rate of diffusion through the tumor capillaries implies a low rate of drug clearance, with a higher intratumoral drug accumulation. Among the drugs used so far for intraperitoneal chemotherapy, the combination of CDDP and DXR appears to be one of the most effective available regimens with acceptable local-regional toxicity. CDDP has also been extensively employed as a single agent for ovarian and gastrointestinal cancers, under both normal and hyperthermic conditions, while intraperitoneally administered DXR appears to be of greater potential efficacy when associated with CDDP and hyperthermia (41.5 degrees C) following cytoreductive surgery. In our clinical experience with this drug combination, DXR showed a much more advantageous plasma/peritoneal AUC ratio than CDDP (162 +/- 113 and 20 +/- 6, respectively). On the other hand, it has been demonstrated that very high intraperitoneal concentrations of CDDP can be achieved without incurring significant systemic toxicity by using intravenous injection of sodium thiosulphate during HIIC. Penetration of the tumor mass by CDDP is greater than DXR. This phenomenon is enhanced by hyperthermia and by hypotonic solutions of sodium chloride used as the perfusate. Following experimental and clinical results of TNF alpha-based isolated limb perfusion for locally advanced soft tissue sarcoma or melanoma, greater efforts are being made to exploit the potential effect of this cytokine used in association with hyperthermia and other drugs (i.e., CDDP and DXR) suitable for intraperitoneal infusion/perfusion. However, it is not yet clear whether the observed effect of TNF alpha on the peritoneal-plasma barrier, which seems to favor the passage of both drugs into the systemic circulation, is overcome by the positive effect of this agent on drug penetration into tumor. Further pharmacologic studies should be undertaken to clarify whether or not these interactions will be of benefit to the patient. Likewise, liposomes, which in animal models seem to favor tumor uptake of encapsulated DXR, should now be tested in the clinical setting.

Gastrointestinal stromal tumors: from a surgical to a molecular approach

Gastrointestinal stromal tumors (GISTs) are the most common mesenchymal tumors of the digestive tract. These tumors span a wide clinical spectrum from benign to malignant and have long been recognized for their nearly absolute resistance to chemotherapy and radiation treatment. We reviewed the worldwide experience on GIST diagnosis, prognosis and treatment and describe our own series. PubMed was searched for references using the terms gastrointestinal stromal tumor, GIST and gastrointestinal sarcoma. Recent reports were given emphasis because GIST is a novel clinical entity and older published work on gastrointestinal sarcomas might be contaminated with other histologic tumor types. At present, surgery is the standard treatment for primary resectable GIST. To increase the activity of conventional chemotherapeutic agents, locoregional therapies are being implemented in the clinical setting. A major breakthrough is the development of a new class of anticancer agents targeting tumor-specific molecular abnormalities. Preliminary results on administration of imatinib mesylate, a signal transduction inhibitor, are particularly encouraging, showing potent activity of this drug against metastatic GIST. Molecular targeting of the critical pathogenetic mechanism underlying GIST might not only revolutionize the strategy to treat locally advanced and metastatic GIST but also improve disease control after macroscopically radical surgery.

Increased TIA-1 gene expression in the tumor microenvironment after locoregional administration of tumor necrosis factor-alpha to patients with soft tissue limb sarcoma

Although it is known that TNF-alpha is effective in the treatment of advanced solid tumors such as melanoma and soft tissue sarcoma, the molecular mechanism underlying its anticancer activity remains unclear. Nineteen patients with locally advanced soft tissue sarcoma underwent isolated limb perfusion with doxorubicin alone (n = 9) or combined with TNF-alpha (n = 10). mRNA from posttreatment tumor biopsies was linearly amplified to create an RNA bank. The transcriptional levels of 22 genes were analyzed by qrt-PCR. On the basis of in vivo findings, we investigated the in vitro gene expression of different cell types representing the tumor microenvironment cell population. TIA-1, which encodes an RNA-binding protein with translation-regulatory functions, was the only gene differentially expressed between the 2 study groups, its transcriptional levels in tumor biopsies from patients receiving TNF-alpha being higher than in those from patients not given the cytokine. In vitro, TIA-1 was expressed by endothelial cells, fibroblasts, CTLs and NK cells. TNF-alpha significantly upregulated TIA-1 gene expression only in endothelial and NK cells. Furthermore, TIA-1 transcriptional levels significantly increased during NK activity, which was enhanced by TNF-alpha. These findings support the hypothesis that TNF-alpha-induced TIA-1 overexpression might sensitize endothelial cells to proapoptotic stimuli present in the tumor microenvironment and enhance NK cell cytotoxic activity against cancer cells.