Biomedical subjects

Alfredo Budillon

Publications and source records attributed to Alfredo Budillon.

18 recordsLinked to original sources

PubMed2026

Transcriptomic signatures of mind-body transformations therapy in breast cancer: Downregulation of the interferon signaling pathway.

BACKGROUND: Growing evidence has shown that Mind-Body Transformations-Therapies (MBT-T) are able to modulate chronic inflammation, a well-known driver of cancer progression and drug resistance. In our previous work, we showed that a specific MBT-T protocol was able to reduce the release of various pro-inflammatory cytokines and chemokines in the sera of patients with breast cancer that completed adjuvant chemotherapy. Despite these clinical observations, the underlying molecular pathways through which this therapy exerts its effects remain unclear. This study aims to address this gap by characterizing genome-wide transcriptional profiles in patients undergoing a novel MBT-T protocol. METHODS: In this proof-of-concept study, patients with breast cancer were randomized into two groups: Group 1 (CTL), receiving standard follow-up care, and Group 2 (MBT-T), receiving standard follow-up plus biweekly MBT-T for 4 months. Blood samples were collected at different timepoints during the treatment. After RNA extraction from whole blood, gene expression was analyzed on twenty-one patients (CTL, n = 7; MBT-T, n = 14) using the nCounter® Human Inflammation Panel (249 genes). RESULTS: Patients undergoing MBT-T showed a significant global downregulation of inflammatory gene expression compared to the control group. The analysis revealed that the Interferon (IFN) signaling pathway was the most significantly suppressed, by downregulation of key genes such as IFIT1, IFIT3, IFI44, MX1 and OASL in the MBT-T group. CONCLUSIONS: MBT-T acts as a biological modulator capable of downregulating key inflammatory pathways at the transcriptional level. These findings provide a genomic basis for the clinical benefits of mind-body interventions in oncology.

Breast cancer↗

PubMed2007

Cetuximab is an active treatment of metastatic and chemorefractory thymoma.

Advanced chemorefractory thymic epithelial tumors still represent a challenge in clinical oncology. A rationale-based therapeutic approach targeting a key pathway should represent the ideal solution in a neoplasm that can over-express Epidermal Growth Factor Receptor (EGFR) in the epithelial component. On the basis of these considerations, two patients with metastatic heavily pretreated disease were evaluated for EGFR expression in the primitive tumor, being considered this data as a basis for an anti EGFR treatment with the monoclonal antibody cetuximab which targets EGFR. A strong EGFR expression was revealed by immunohistochemistry in the two cases considered, thus the patients received cetuximab and reported a partial response as assessed by Computed Tomography (CT), Positron Emission Tomography (PET) and fused PET-CT after three months of therapy. Therefore, both patients are still on therapy. This preliminary experience suggests that cetuximab may be a useful therapeutic choice in advanced pre-treated thymic tumors.

Adult↗

PubMed2007

R115777 (Zarnestra)/Zoledronic acid (Zometa) cooperation on inhibition of prostate cancer proliferation is paralleled by Erk/Akt inactivation and reduced Bcl-2 and bad phosphorylation.

Zoledronic acid (ZOL) has proved activity in bone metastases from prostate cancer through inhibition of mevalonate pathway and of prenylation of intracellular proteins. We have reported that ZOL synergizes with R115777 farnesyltransferase inhibitor (FTI, Zarnestra) in inducing apoptosis and growth inhibition on epidermoid cancer cells. Here, we have studied the effects of the combination of these agents in prostate adenocarcinoma models and, specifically, on androgen-independent (PC3 and DU145) and -dependent (LNCaP) prostate cancer cell lines. We have found that ZOL and R115777 were synergistic in inducing both growth inhibition and apoptosis in prostate adenocarcinoma cells. These effects were paralleled by disruption of Ras-->Erk and Akt survival pathways, consequent decreased phosphorylation of both mitochondrial bcl-2 and bad proteins, and caspase activation. Finally, ZOL/R115777 combination induced cooperative effects also in vivo on tumor growth inhibition of prostate cancer xenografts in nude mice with a significant survival increase. These effects were paralleled by enhanced apoptosis and inactivation of both Erk and Akt. In conclusions, the combination between ZOL and FTI leads to enhanced anti-tumor activity in human prostate adenocarcinoma cells likely through a more efficacious inhibition of ras-dependent survival pathways and consequent bcl-related proteins-dependent apoptosis.

Adenocarcinoma↗

PubMed2006

Molecular dynamics simulation and automated docking of the pro-apoptotic Bax protein and its complex with a peptide designed from the Bax-binding domain of anti-apoptotic Ku70.

Bax, a multi-domain protein belonging to the large family of Bcl-2 proteins, has a pivotal role for the initiation of the cytochrome c-mediated apoptosis, a vital physiologic process to eliminate damaged or unwanted cells. In response to specific stimuli Bax translocates from cytosol to mitochondria outer membrane where a process of oligomerization occurs with pore formation through which cytochrome c and other death molecules escape. The pro-death action of Bax is regulated by the interaction with other pro-survival proteins. However, the conformational changes and the structural details necessary for homo and hetero interaction with other regulating proteins are largely unknown. This article reports a combined investigation of molecular dynamics (MD) simulation and automated docking that evidence the molecular regions of Bax involved in the binding with anti-apoptotic exapeptide (Bip) designed from Ku70, a subunit of the protein complex essential for non-homologous DNA repair but that inhibits also the Bax translocation to mitochondria. Since Bip suppresses apoptosis induced by several anti-cancer drugs, it appears relevant to achieve a better understanding of the structural and dynamical aspects that characterize the Bip-Bax complex in view of potential therapeutic implications. The present results show that the Bax region with the highest affinity for Bip is located in proximity of BH3 homology domain of Bax and also involves the alpha-helices 1 and 8. Moreover, the comparison of essential motions of Bax at 300 and 400 K before and after the formation of the complex with Bip evidences how the binding with the exa-peptide affects the collective motions of specific molecular districts of Bax considered to have functional relevance.

Amino Acid Sequence↗

PubMed2006

Synergistic antitumor activity of epidermal growth factor receptor tyrosine kinase inhibitor gefitinib and IFN-alpha in head and neck cancer cells in vitro and in vivo.

PURPOSE: Epidermal growth factor receptor (EGFR) overexpression has been implicated in the development of head and neck squamous cell carcinomas (HNSCC) and represents a potential therapeutic target for this disease. We have reported previously that growth inhibitory concentrations of IFN-alpha enhance the expression and activity of EGFR and that this effect could represent an escape mechanism to the growth inhibition and apoptotic cell death induced by IFN-alpha. In this study, we investigate whether the combination of IFN-alpha and gefitinib (Iressa, AstraZeneca Pharmaceuticals, Macclesfield, United Kingdom), a selective EGFR tyrosine kinase inhibitor, might have a cooperative antitumor effect on HNSCC-derived cell lines. EXPERIMENTAL DESIGN: The interaction of IFN-alpha and gefitinib was evaluated in vitro on HNSCC-derived cell lines by median drug effect analysis calculating a combination index with CalcuSyn software and in vivo by using HNSCC xenografts in nude mice. The mechanism of gefitinib and IFN-alpha interactions was also studied by analysis of cell cycle kinetics, apoptosis assays, and Western blotting of EGFR signal transduction components. RESULTS: Simultaneous exposure to gefitinib and IFN-alpha produced synergistic antiproliferative and proapoptotic effects compared with single drug treatment. Furthermore, daily treatment of gefitinib (50 mg/kg p.o.) in combination with an IFN-alpha regimen (50,000 units s.c. three times weekly) induced tumor growth delay and increased survival rate on established HNSCC xenografts in nude mice. Moreover, the concomitant treatment with gefitinib suppressed the stimulation of extracellular signal-regulated kinase phosphorylation/activity induced by IFN-alpha both in vitro and in vivo. CONCLUSION: The observed cooperative antitumor effects could be, at least in part, explained by the inhibition exerted by gefitinib of an IFN-alpha-induced EGF-dependent survival pathway, which involves extracellular signal-regulated kinase activation. These results provide a rationale for the clinical evaluation of gefitinib in combination with IFN-alpha in HNSCC.

Animals↗

PubMed2006

Mechanisms of disease: Preclinical reports of antineoplastic synergistic action of bisphosphonates.

For patients with malignant bone disease, bisphosphonate therapy is the standard treatment. Preclinical and preliminary clinical data suggest that bisphosphonates have direct or indirect antitumor effects: they affect growth-factor release, cancer-cell adhesion, invasion and viability, angiogenesis, and apoptosis of cancer cells. These effects might be enhanced through co-administration with chemotherapy agents, biological agents, or both. We survey the biochemical pathways and molecular targets of bisphosphonates, and discuss the molecular mechanisms of these antitumor effects, as well as the documented antineoplastic preclinical effects of bisphosphonates used in combination with cytotoxic and biological drugs. Moreover, the positive interactions between bisphosphonates and farnesyltransferase inhibitors, KIT receptor tyrosine kinase inhibitors (e.g. imatinib mesylate) and cyclo-oxygenase-2 inhibitors are discussed in relation to their potential synergistic and additive effects. We briefly discuss identification of new molecular targets of bisphosphonates from genomic and proteomic analysis, and highlight the cellular consequences of drug-related enzyme inhibition.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2006

Emerging anti-cancer molecular mechanisms of aminobisphosphonates.

Bone metastases are common in patients with many types of cancer, especially breast and prostate cancer--in which the incidence is approximately 70% among patients with advanced metastatic disease. Aminobisphosphonates (NBPs) have entered clinical practice in the treatment of bone metastases from several neoplasms, including breast and prostate adenocarcinoma, as a result of their anti-resorption properties. However, evidence has accumulated on the direct anti-tumour effects of NBPs. This review describes the metabolic pathways that are putative molecular targets of NBPs and that are involved in the prenylation processes of several intracellular small GTP-binding proteins (ras family related proteins). The latter regulate the intracellular survival and proliferative pathways of tumour cells and could be the intracellular molecular targets of the NBPs responsible for the direct anti-cancer effects, even if definitive conclusions cannot be drawn at present. Different mechanisms have been reported to account for the anti-neoplastic action of NBPs, including: the induction of apoptosis; cell cycle perturbations; and anti-invasive, anti-migration and anti-angiogenic effects. Moreover, this review describes the most important clinical studies that demonstrate the activity of NBPs in preventing skeletal-related events induced by bone metastases. The main pharmacokinetic pitfalls of NBPs are described, and methods of overcoming these pitfalls through the use of liposome vehicles are proposed. Finally, the principal pre-clinical studies on the interaction between NBPs and other biological agents are also described; these studies may enable reductions in the in vivo NBP concentrations required to achieve anti-tumour activity. To date, however, the real molecular targets of NBPs are not completely known and new technological platforms are required in order to detect them and to develop new anti-cancer strategies based on the use of NBPs.

Antineoplastic Agents↗

PubMed2006

Changes in bone resorption and vascular endothelial growth factor after a single zoledronic acid infusion in cancer patients with bone metastases from solid tumours.

Zoledronic acid (Zometa, ZOL) is increasingly used to treat tumour-induced bone disease, and is also reported to have antiangiogenic properties in vivo. In this study, we have investigated the correlations between changes in the proangiogenic cytokine, vascular endothelial growth factor (VEGF), and markers of bone resorption in a cohort of patients with metastatic bone disease, following a single infusion of ZOL. Twenty-four consecutive selected cancer patients with scintigraphic and radiographic evidence of bone metastases were treated for the first time with a single infusion of 4 mg ZOL. Patients were considered ineligible if they had received any steroid therapy, radiotherapy, chemotherapy, immunotherapy or haemopoietic growth factors in the 4 weeks before or during the study period. Circulating levels of VEGF and beta crosslinked type I collagen C-telopeptide (betaCTX) were measured at base-line and at 1, 2, 7 and 21 days following ZOL infusion. The majority of our patients (23/24) developed a significant reduction in circulating levels of betaCTX at just 1 day after the single zoledronic acid infusion, median percentage decrease 67.05% (95% CI, 52.39%; 76.27%). This reduction persisted at all following time points in almost all subjects in our patient population (day 2, 95.8%; day 7, 100%; day 21, 91.7%). The median decrease at day 2 was 85.67% (95% CI, 78.23%; 90.16%); at day 7, 67.38% (95% CI, 67.38%; 86.98); and at day 21, 76.89% (95% CI, 35.00%; 83.16%). Moreover, a linear regression model with variance analysis demonstrated a statistically significant correlation between median VEGF and betaCTX circulating levels at each of the time points (1, 2, 7 and 21 days after ZOL infusion). The present work demonstrates that a single infusion of ZOL was able to induce a rapid and long lasting decrease of betaCTX plasma levels in the majority (23/24) of the included cancer patients. Furthermore, we found that there is a correlation between the levels of VEGF and betaCTX following ZOL treatment. Future clinical trials should be designed to prospectively evaluate the prognostic role of reduction of betaCTX and VEGF in response to ZOL to predict clinical and skeletal outcome.

Adult↗

PubMed2005

Phase II study of temozolomide plus pegylated liposomal doxorubicin in the treatment of brain metastases from solid tumours.

OBJECTIVE: A combination regimen of temozolomide (TMZ) and pegylated liposomal doxorubicin has been evaluated in the treatment of brain metastases from solid tumours. STUDY DESIGN: Nineteen consecutive patients (pts) have been enrolled in a prospective phase II trial and treated with TMZ 200 mg/m2 (days 1-5) and pegylated liposomal doxorubicin 35 mg/m2 (day 1) every 28 days. The study was prospectively projected according to the Simon's two-stage optimal design. RESULTS: Major toxicities have been grade III neutropenia and thrombocytopenia in one patient (pt) and grade III erythrodisesthesia in two pts. Three pts achieved a complete response (CR) and four a partial response (PR), for an overall response rate of 36.8% (95% CI: 19.1-59.2), which exceeded the target activity in the study design. A significant improvement in quality of life was demonstrated by FACT-G analysis. The median Progression Free Survival (PFS) was 5.5 (95% CI: 2.7-8.2) months while the median Overall Survival (OS) was 10.0 months (95% CI: 6.3-13.7). CONCLUSIONS: The TMZ/pegylated liposomal doxorubicin regimen was well tolerated with an encouraging activity in brain metastases from solid tumours.

Administration, Oral↗

PubMed2005

Chemotherapy regimen GOLF induces apoptosis in colon cancer cells through multi-chaperone complex inactivation and increased Raf-1 ubiquitin-dependent degradation.

The multi-drug combination of oxaliplatin (OXA), 5-Fluorouracil (5-FU) and leucovorin (LF) is currently considered as the gold standard treatment for metastatic colorectal carcinoma. In previous studies, we have studied a chemotherapy regimen containing gemcitabine (GEM), OXA, LF, and 5-FU (named GOLF regimen) that has shown a good safety profile and highly significant anti-tumor activity. In the present study, we have investigated on the anti-tumour mechanisms of GOLF in human colon cancer HT-29 and WiDr cell lines. We have found that GOLF induced growth inhibition that was largely caused by apoptosis differently from other combinations. Moreover, the different drugs composing GOLF were highly synergistic in inducing growth inhibition. Apoptosis induced by GOLF combination was paralleled by PARP cleavage and caspase 9 and 3 activation that were not recorded in the other combinations. An about 85% decrease of the activity of Erk and Akt was found in GOLF-treated cells. These effects were likely due to decreased expression of the upstream activator Raf-1 and of Akt itself, respectively. The intracellular levels of these signalling components can be post-translationally regulated by ubiquitin-dependent degradation through proteasome. Therefore, we have evaluated the expression of some chaperone components and we have found that GOLF did not affect the expression of both heat shock protein (HSP) 90 and 27 but induced an about 90% increase of HSP70 levels suggesting the inactivation of the multi-chaperone complex. Moreover, an about 4-fold increase of the ubiquitination of Raf-1 was also found and the addition for 12 h of 10 microM proteasome inhibitor lactacystin caused an accumulation of the ubiquitinated isoforms of Raf-1. In conclusions, GOLF was a combination highly synergistic in inducing both growth inhibition and apoptosis of colon cancer cells. These effects likely occurred through the disruption of critical survival pathways and the inactivation of multi-chaperone complex.

Antineoplastic Combined Chemotherapy Protocols↗

PubMed2005

Electromagnetic fields at mobile phone frequency induce apoptosis and inactivation of the multi-chaperone complex in human epidermoid cancer cells.

The exposure to non-thermal microwave electromagnetic field (MW-EMF) at 1.95 MHz, a frequency used in mobile communication, affects the refolding kinetics of eukaryotic proteins (Mancinelli et al., 2004). On these basis we have evaluated the in vivo effect of MW-EMF in human epidermoid cancer KB cells. We have found that MW-EMF induces time-dependent apoptosis (45% after 3 h) that is paralleled by an about 2.5-fold decrease of the expression of ras and Raf-1 and of the activity of ras and Erk-1/2. Although also the expression of Akt was reduced its activity was unchanged likely as a consequence of the increased expression of its upstream activator PI3K. In the same experimental conditions an about 2.5-fold increase of the ubiquitination of ras and Raf-1 was also found and the addition for 12 h of proteasome inhibitor lactacystin at 10 microM caused an accumulation of the ubiquitinated isoforms of ras and Raf-1 and counteracted the effects of MW-EMF on ras and Raf-1 expression suggesting an increased proteasome-dependent degradation induced by MW-EMF. The exposure of KB cells to MW-EMF induced a differential activation of stress-dependent pathway with an increase of JNK-1 activity and HSP70 and 27 expression and with a reduction of p38 kinase activity and HSP90 expression. The overexpression of HSP90 induced by transfection of KB cells with a plasmid encoding for the factor completely antagonized the apoptosis and the inactivation of the ras --> Erk-dependent survival signal induced by MW-EMF. Conversely, the inhibition of Erk activity induced by 12 h exposure to 10 mM Mek-1 inhibitor U0126 antagonized the effects induced by HSP90 transfection on apoptosis caused by MW-EMF. In conclusion, these results demonstrate for the first time that MW-EMF induces apoptosis through the inactivation of the ras --> Erk survival signaling due to enhanced degradation of ras and Raf-1 determined by decreased expression of HSP90 and the consequent increase of proteasome dependent degradation.

Apoptosis↗

PubMed2005

New pharmacokinetic and pharmacodynamic tools for interferon-alpha (IFN-alpha) treatment of human cancer.

Interferon alpha (IFN-alpha) has been widely used in the treatment of human solid and haematologic malignancies. Although the antitumour activity of IFN-alpha is well recognised at present, no major advances have been achieved in the last few years. Recent findings have provided new information on the molecular mechanisms of the antitumour activity of the cytokine. In fact, IFN-alpha appears to block cell proliferation, at least in part, through the induction of apoptotic effects. This cytokine can also regulate the progression of tumour cells through the different phases of the cell cycle inducing an increase of the expression of the cyclin-dependent kinase inhibitors p21 and p27. However, it must be considered that IFN-alpha is a physiologic molecule with ubiquitously expressed receptors that is likely to activate survival mechanisms in the cell. We have recently identified an epidermal growth factor (EGF) Ras-dependent protective response to the apoptosis induced by IFN-alpha in epidermoid cancer cells. The identification of tissue- and/or tumour-specific survival pathways and their selective targeting might provide a new approach to improve the efficacy of IFN-alpha-based treatment of human cancer. Moreover, new pegylated species of IFN-alpha are now available with a more favourable pharmacokinetic profile. We will review these achievements, and we will specifically address the topic of IFN-alpha-based molecularly targeted combinatory antitumour approaches.

Antineoplastic Agents↗

PubMed2005

Targeted therapies and non-small cell lung cancer: methodological and conceptual challenge for clinical trials.

PURPOSE OF REVIEW: Targeted therapies are emerging as important drugs in the treatment of advanced non-small cell lung cancer (NSCLC). Within the past months, there have been considerable contributions to this topic. The results of several important clinical trials have been published. Furthermore, laboratory results have significantly contributed to clear out some molecular mechanisms regulating sensitivity or resistance to these drugs and to provide rational basis for further clinical studies. RECENT FINDINGS: A great part of recently published research on targeted agents in NSCLC regards EGFR inhibitors. Following the demonstration of activity of gefitinib in patients pretreated with chemotherapy, four large randomized trials testing the addition of gefitinib or erlotinib to first-line chemotherapy have been conducted, but failed to show any advantage. Interestingly, erlotinib has shown efficacy compared with placebo in pretreated patients. Mutations in the EGFR gene have shown a strong predictive role for sensitivity to EGFR inhibitors. A number of other targeted agents are currently under investigation: most of the phase II trials maintain a traditional methodology, with response rate as primary measure of activity. SUMMARY: Recent advances will lead to a rapid expansion of further studies aimed to define the best way to use targeted agents in NSCLC. Several methodological issues are still open. The proper selection of patients, the choice of the best study design and the most appropriate end-point for early clinical trials, and the correct modality to integrate these drugs with traditional chemotherapy represent the most challenging points that research is called to answer in the near future.

Antineoplastic Agents↗

PubMed2004

The farnesyl transferase inhibitor R115777 (Zarnestra) synergistically enhances growth inhibition and apoptosis induced on epidermoid cancer cells by Zoledronic acid (Zometa) and Pamidronate.

Pamidronate (PAM) and zoledronic acid (ZOL) are aminobisphosphonates (BPs) able to affect the isoprenylation of intracellular small G proteins. We have investigated the antitumor activity of BPs and R115777 farnesyl transferase inhibitor (FTI) against epidermoid cancer cells. In human epidermoid head and neck KB and lung H1355 cancer cells, 48 h exposure to PAM and ZOL induced growth inhibition (IC(50) 25 and 10 microM, respectively) and apoptosis and abolished the proliferative and antiapoptotic stimuli induced by epidermal growth factor (EGF). In these experimental conditions, ZOL induced apoptosis through the activation of caspase 3 and a clear fragmentation of PARP was also demonstrated. A strong decrease of basal ras activity and an antagonism on its stimulation by EGF was recorded in the tumor cells exposed to BPs. These effects were paralleled by impaired activation of the survival enzymes extracellular signal regulated kinase 1 and 2 (Erk-1/2) and Akt that were not restored by EGF. Conversely, farnesol induced a recovery of ras activity and antagonized the proapoptotic effects induced by BPs. The combined treatment with BPs and R115777 resulted in a strong synergism both in growth inhibition and apoptosis in KB and H1355 cells. The synergistic activity between the drugs allowed BPs to produce tumor cell growth inhibition and apoptosis at in vivo achievable concentrations (0.1 micromolar for both drugs). Moreover, the combination was highly effective in the inhibition of ras, Erk and Akt activity, while farnesol again antagonized these effects. In conclusion, the combination of BPs and FTI leads to enhanced antitumor activity at clinically achievable drug concentrations that resides in the inhibition of farnesylation-dependent survival pathways and warrants further studies for clinical translation.

Alkyl and Aryl Transferases↗

PubMed2004

Expression of COX-2, mPGE-synthase1, MDR-1 (P-gp), and Bcl-xL: a molecular pathway of H pylori-related gastric carcinogenesis.

Helicobacter pylori up-regulates cyclo-oxygenase-2 (COX-2) expression, which in turn is involved in tumourigenesis. Recently, a causal link between COX-2 and multidrug resistance 1 (MDR-1) gene expression, implicated in cancer chemoresistance, has been demonstrated. Thus, the expression of COX-2 and the downstream enzyme involved in PGE2 biosynthesis, microsomal PGE-synthase1 (mPGES1), was correlated with P-gp, the product of MDR-1, and the anti-apoptotic protein, Bcl-xL, in gastric biopsies from patients with H pylori infection and in patients with gastric cancer. In a retrospective analysis of endoscopic and pathology files, 40 H pylori-negative patients (Hp-), 50 H pylori-positive patients who responded to eradication therapy (Hp+R), 84 H pylori-positive patients who did not respond to eradication therapy (Hp+NR), and 30 patients with gastric cancer (18 intestinal and 12 diffuse types) were selected. COX-2, mPGES1, P-gp, and Bcl-xL were detected by immunohistochemistry. COX-2, mPGES1, P-gp, and Bcl-xL expression was undetectable in gastric mucosa from Hp- patients. By contrast, COX-2 and mPGES1 expression was detected in 42% and 44% of Hp+R patients, respectively, and in up to 66% (range 63-66%) of Hp+NR patients (p < 0.05). The expression of COX-2 and mPGES1 correlated significantly (p < 0.0001) with that of P-gp and Bcl-xL. High levels of COX-2, mPGES1, P-gp, and Bcl-xL expression were found in intestinal-type gastric cancer samples. In conclusion, H pylori-dependent induction of COX-2 and mPGES1 is associated with enhanced production of P-gp and Bcl-xL that may contribute to gastric tumourigenesis and resistance to therapy.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed2004

Frequent overexpression of multiple ErbB receptors by head and neck squamous cell carcinoma contrasts with rare antibody immunity in patients.

In an effort to elucidate the role of ErbB receptors in human head and neck squamous cell carcinoma (HNSCC), expression abnormalities and subcellular localization of epidermal growth factor receptor (EGFR), ErbB2, ErbB3, and ErbB4 were investigated along with EGF and tenascin by immunohistochemistry in 38 carcinomas as compared to adjacent normal mucosa of 24 cases. Although tumour-specific overexpression affected each ErbB receptor (EGFR 47%, ErbB2 29%, ErbB3 21%, ErbB4 26%), EGFR abnormalities were most prevalent. The latter, and overexpression of more than two ErbB receptors in the same tumour, which always included EGFR, correlated with metastatic disease. ErbB products were specifically detected on the cell membrane and in the cytoplasm. In contrast, ErbB4 was uniquely localized to the nucleus in 7 carcinomas and a tumour-derived cell line, indicating a role for regulated intramembrane proteolysis resulting in nuclear ErbB4 translocation in HNSCC. Expression of prototype ligand EGF or low-affinity stromal activator tenascin correlated significantly with EGFR overexpression, implying chronic EGFR activation. Simultaneous overexpression of additional ErbB receptors in most of these cases suggested recurrent involvement of receptor heterodimers. In spite of frequent ErbB receptor alterations, autologous ErbB serum antibodies were rare, with only 1 of 38 tumour patients exhibiting an ErbB2-specific immune response. Based on upregulation of several known immunosuppressive molecules, scarcity of ErbB-specific antibodies is consistent with attenuation of natural tumour-specific immune responses in HNSCC.

Antibody Formation↗

PubMed2004

Alpha-interferon and its effects on signalling pathways within cells.

Interferon-alpha (IFNalpha) is a recombinant protein widely used in the therapy of several neoplasms such as myeloma, renal cell carcinoma, epidermoid cervical and head and neck tumours and melanoma. IFNalpha, the first cytokine to be produced by recombinant DNA technology, has emerged as an important regulator of cancer cell growth and differentiation, affecting cellular communication and signal transduction pathways. However, the way by which tumour cell growth is directly suppressed by IFNalpha is not well known. Wide evidence exists on the possibility that cancer cells undergo apoptosis after the exposure to the cytokine. Here we will review the consolidate Signal transducer and activator of transcription (STAT)-dependent mechanism of action of IFNalpha and the supposed mechanism of apoptosis induction by IFNalpha. We will discuss data obtained by us and others on the triggering of the stress-dependent kinase pathway and on the modulation of protein synthesis machinery induced by IFNalpha and their correlations with the apoptotic process. Until today, inconsistent data have been obtained regarding the clinical effectiveness of IFNalpha in the therapy of solid tumours. In fact, the benefit of IFNalpha treatment is limited to some neoplasms while others are completely or partially resistant. The mechanisms of tumour resistance to IFNalpha have been studied in vitro. The alteration of JAK- Signal transducer and activator of transcription components of the IFNalpha-induced signalling, can be indeed a mechanism of resistance to IFN and cross talks between IFNalpha and survival signals has been also described. However, we have recently described a reactive mechanism of protection of tumour cells from the apoptosis induced by IFNalpha dependent on the epidermal growth factor (EGF)-mediated Ras/extracellular signal regulated kinase (Erk) signalling. The involvement of the Ras->Erk pathway in the protection of tumour cells from the apoptosis induced by IFNalpha is further demonstrated by both Ras inactivation by RASN17 transfection and mitogen extracellular signal regulated kinase 1 (Mek-1) inhibition by exposure to PD098059. These data strongly suggest that the specific disruption of the latter could be a useful approach to potentiate the antitumour activity of IFNalpha against human tumours based on the new mechanistic insights achieved in the last years.

Apoptosis↗

PubMed2003

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

High expression of the epidermal growth factor receptor (EGFR) has been implicated in the development of squamous-cell carcinomas of head and neck (SCCHN). ZD1839 ('Iressa') is an orally active, selective EGFR-TKI (EGFR-tyrosine kinase inhibitor) that blocks signal transduction pathways implicated in proliferation and survival of cancer cells, and other host-dependent processes promoting cancer growth. We have demonstrated that ZD1839 induces growth arrest in SCCHN cell lines by inhibiting EGFR-mediated signaling. Cell cycle kinetic analysis demonstrated that ZD1839 induces a delay in cell cycle progression and a G1 arrest together with a partial G2/M block; this was associated with increased expression of both p27(KIP1) and p21(CIP1/WAF1) cyclin-dependent kinase (CDK) inhibitors. The activity of CDK2, the main target of CIP/KIP CDK inhibitors, was reduced in a dose-dependent fashion after 24 h of ZD1839 treatment and this effect correlated to the increased amount of p27(KIP1) and p21(CIP1/WAF1) proteins associated with CDK2-cyclin-E and CDK2-cyclin-A complexes. In addition, ZD1839-induced growth inhibition was significantly reduced in cell transfectants expressing p27(KIP1) or p21(CIP1/WAF1) antisense constructs. Overall, these results as well as the timing of the effect of ZD1839 on G1 arrest and p27(KIP1) and p21(CIP1/WAF1) upregulation, suggest a mechanistic connection between these events.

Antineoplastic Agents↗