Effect of adjuvant trastuzumab treatment in conventional clinical setting: an observational retrospective multicenter Italian study.

Clinical trials have shown the efficacy of trastuzumab-based adjuvant therapy in HER2-positive breast cancers, but routine clinical use awaits evaluation of compliance, safety, and effectiveness. Adjuvant trastuzumab-based therapy in routine clinical use was evaluated in the retrospective study GHEA, recording 1,002 patients treated according to the HERA protocol between March 2005 and December 2009 in 42 Italian oncology departments; 874 (87.23 %) patients completed 1-year trastuzumab treatment. In 128 patients (12.77 %), trastuzumab was withdrawn due to cardiac or non-cardiac toxicity (28 and 29 patients, respectively), disease progression (5 patients) or the clinician's decision (66 patients). In addition, 156 patients experienced minor non-cardiac toxicities; 10 and 44 patients showed CHF and decreased LVEF, respectively, at the end of treatment. Compliance and safety of adjuvant trastuzumab-based therapy in Italian hospitals were high and close to those reported in the HERA trial. With a median follow-up of 32 months, 107 breast cancer relapses were recorded (overall frequency, 10.67 %), and lymph node involvement, estrogen receptor negativity, lymphoid infiltration, and vascular invasion were identified as independent prognostic factors for tumor recurrence, indicating that relapses were associated with advanced tumor stage. Analysis of site and frequency of distant metastases showed that bone metastases were significantly more frequent during or immediately after trastuzumab (<18 months from the start of treatment) compared to recurrences in bone after the end of treatment and wash-out of the drug (>18 months from the start of treatment) (35.89 vs. 14.28 %, p = 0.0240); no significant differences were observed in recurrences in the other recorded body sites, raising the possibility that the protection exerted by trastuzumab is lower in bone metastases.

Biology, prognosis and response to therapy of breast carcinomas according to HER2 score.

BACKGROUND: The standardization of the HER2 score and recent changes in therapeutic modalities points to the need for a reevaluation of the role of HER2 in recently diagnosed breast carcinoma. PATIENTS AND METHODS: A multicenter, retrospective study of 1794 primary breast carcinomas diagnosed in Italy in 2000/2001 and scored in HER2 four categories according to immunohistochemistry was conducted. RESULTS: Ductal histotype, vascular invasion, grade, MIB1 positivity, estrogen and progesterone receptor expression differed significantly in HER2 3+ tumors compared with the other categories. HER2 2+ tumors almost showed values intermediate between those of the negative and the 3+ subgroups. The characteristics of HER2 1+ tumors were found to be in between those of HER2 0 and 2+ tumors. With a median follow-up of 54 months, HER2 3+ status was associated with higher relapse rates in node-positive and node-negative subgroups, while HER2 2+ only in node positive. Analysis of relapses according to type of therapy provided evidence of responsiveness of HER2-positive tumors to chemotherapy, especially taxanes. CONCLUSIONS: The present prognostic significance of HER2 is correlated to receptor expression level and points to the need to consider HER2 2+ and HER2 3+ tumors as distinct diseases with different outcomes and specific features.

Toll-like receptor agonists regulate beta-defensin 2 release in hair follicle.

BACKGROUND: Skin is constantly in contact with different pathogens, which are present in the environment. The hair follicle is particularly susceptible to this microbial invasion as it offers an easy way of access for microorganisms; for this reason it is equipped with defence mechanisms to avoid frequent infections. OBJECTIVES: To analyse the expression pattern of four different members of the toll-like receptor (TLR) family in murine hair follicles and to evaluate the effects of their activation by their specific microbiota-derived agonists, in terms of production of the antimicrobial peptide beta-defensin 2 (DEFB2). METHODS: TLR and DEFB2 protein expression was investigated by immunohistochemistry on murine skin samples. RESULTS: Murine hair follicle expresses TLR2, TLR4 and TLR5; agonists of TLR2, TLR4 and TLR5 but not of TLR9 induced DEFB2 production in this compartment. The strongest DEFB2 expression was observed following TLR4 activation by lipopolysaccharide. CONCLUSIONS: Our data show that the hair follicle is equipped with TLR2, TLR4 and TLR5, and that these receptors are able to respond to microbial stimuli inducing the production of DEFB2 by epithelial cells. This immune response might be important in preserving the skin from microorganism infections.

Role of exon-16-deleted HER2 in breast carcinomas.

A splice variant of the human gene HER2, lacking exon-16 (DeltaHER2) which encodes a small extracellular region, has been described. This altered receptor forms disulfide bond-stabilized homodimers. We report here that the DeltaHER2 splice variant represents about 9% of the HER2 mRNA obtained from most of the 46 breast carcinoma samples with HER2 expression levels ranging from 3+ to 0 by HercepTest. Analysis of human cells transfected with DeltaHER2 or wild-type (WT) cDNA revealed no growth of WT cells in nude mice, whereas clones expressing 10-fold less DeltaHER2 were tumorigenic. Unlike WT transfectants, DeltaHER2-expressing cells showed low sensitivity to two new therapeutic drugs targeting receptors of the HER family (ZD1839 and Trastuzumab), whereas an inhibitor of the HER2 tyrosine kinase domain (Emodin) blocked activation of both DeltaHER2 and WT transfectants. Taken together, our findings indicate that the DeltaHER2 transcript encodes the transforming form of the oncoprotein. It is plausible that malignant transformation arises when a critical threshold of DeltaHER2 is reached in HER2-overexpressing tumors. Specific inhibitors of HER2 catalytic activity represent a promising approach to therapy of HER2-overexpressing tumors.

Caveolin-1 is expressed on multipotent cells of hair follicles and might be involved in their resistance to chemotherapy.

BACKGROUND: Caveolin-1 is the principal protein that composes caveolae, which are vesicular invaginations present on the plasma membrane of different cell types. Caveolae are involved in a variety of cellular functions including regulation of proliferation rate and resistance to chemotherapeutic drugs. Chemotherapy frequently induces alopecia which is reversible most probably due to the low proliferative rate of hair follicle stem cells and due to the expression of proteins which confer resistance. OBJECTIVES: Using a specific animal model and immunohistochemistry, we analysed the expression of both caveolin-1 and the cell proliferation marker beta-catenin, at different stages of the hair follicle cycle, both before and after doxorubicin (DXR) -induced alopecia. METHODS: Seven-week-old C57BL/6 mice were depilated in order to synchronize hair follicle cycle in the anagen phase. Chemotherapy with DXR 15 mg kg(-1) was used to induce alopecia. Control and treated mice were then sacrificed at precise time points and caveolin-1 expression in hairs at different stages of the cycle were analysed by immunohistochemistry. By double immunofluorescence, colocalization of caveolin-1 and cytokeratin-15 was confirmed in the bulge region. The state of proliferation of cells composing hair follicle was assessed by beta-catenin immunohistochemistry. RESULTS: Caveolin-1 was expressed by the cells of the bulge area, the multipotent compartment of the hair follicle, during all phases of growth (anagen), regression (catagen) and resting (telogen). During the anagen phases, nuclear beta-catenin labelling was not observed in bulge cells, but rather in the deeper portion of the follicle. Damaged hair follicles from DXR-treated mice presented bulge cells which still expressed caveolin-1, suggesting that this protein might play a role in their drug resistance. As expected, no beta-catenin nuclear staining was detectable in DXR-treated hair follicles, indicating the complete lack of proliferative processes. The differential localization of caveolin-1 and beta-catenin suggests that the mutually exclusive expression of these proteins is useful for correct hair regrowth, whether during the physiological cycle or after chemotherapy-induced alopecia. CONCLUSIONS: Expression of caveolin-1 within the multipotent cell compartment of the hair follicle can explain the resistance of bulge cells to many chemotherapeutics, suggested by the reversibility of chemotherapy-induced alopecia.

The 67 kDa laminin receptor increases tumor aggressiveness by remodeling laminin-1.

The association between expression of the 67 kDa laminin receptor (67LR) and tumor aggressiveness has been convincingly demonstrated although the exact function of this molecule in the metastatic process has remained unclear. In this study, we tested whether the laminin-1, upon interaction with 67LR, promotes tumor cell aggressiveness; the investigation was based on: (i) the previous demonstration that soluble 67LR, as well as a 20-amino-acid peptide corresponding to the 67LR laminin binding site, changes the conformation of laminin upon interaction with this adhesion molecule and (ii) the known relevance of microenvironment remodeling by the tumor, leading to structural modification of extracellular matrix components in tumor progression. MDAMB231 breast carcinoma cells plated on peptide G-treated laminin-1 exhibited a polygonal array of actin filament bundles compared with cells seeded on native laminin-1 which presented the actin bundles organized as multiple cables parallel to margins. Furthermore, in cells seeded on peptide G-treated laminin-1, 67LR was distinct from the alpha6 integrin subunit in filopodia protrusions in addition to colocalizing with this integrin in focal adhesion plaques as it occurs when cells are plated on native laminin-1. In addition to differences in tumor cell adhesion and migration found in cells exposed to peptide G-treated vs native laminin-1, breast carcinoma cells seeded on modified laminin-1 showed a 6-fold increase in invasion capability compared with cells seeded on unmodified laminin-1. Alterations in actin organization as well as adhesion, migration and especially invasion observed in MDAMB231 cells in the presence of peptide G-treated laminin-1 were even found in MDAMB231 cells that, after selection for 67LR high expression, were seeded on native laminin-1. As the 67LR shedding is proportional to its expression level, these findings indicate a role for 67LR in changing laminin structure. Expression analysis of 97 genes encoding proteins that mediate cell matrix interactions, revealed significant differences between cells exposed to modified vs unmodified laminin-1 in 19 genes, 17 of which--including those encoding alpha3 integrin, extracellular matrix protein 1, proteolytic enzymes (such as MT1-MMP, stromelysin-3 and cathepsin L) and their inhibitors--were up-modulated in cells treated with modified laminin-1. Zymogram analysis clearly indicated a significant increase in the activity of the gelatinolytic enzyme MMP-2 in the culture supernatant from cells exposed to modified laminin-1, without an increase in mRNA abundance as observed in microarray analysis. Invasiveness of tumor cells conditioned by modified laminin-1, evaluated as the capability to cross Matrigel basement, was significantly more inhibited by MMPinhibitor TIMP-2 than invasiveness induced by native laminin-1. Taken together, our findings indicate that the role of 67LR in tumor aggressiveness rests in its ability to modify laminin-1 thereby activating proteolytic enzymes that promote tumor cell invasion through extracellular matrix degradation.

Antibody response after vaccination with antigen-pulsed dendritic cells.

Dendritic cells (DCs) are the most potent antigen-presenting cells of the immune system capable of initiating immune responses to antigens. It is also well documented that cancer patients often experience anergy against tumor antigens. In this study we selected the best protocol for inducing the production of antibodies against the HER2 oncoprotein using DCs to overcome anergy. Murine DCs were pulsed in vitro, using different protocols, with recombinant HER2 fused to a human Fc (in order to improve DC antigen uptake) and were used to vaccinate mice. The obtained results indicate that antigen-pulsed DCs can induce an antibody response and that adding CpG after antigen pulsing greatly increases anti-HER2 antibody production.

Combination of a CpG-oligodeoxynucleotide and a topoisomerase I inhibitor in the therapy of human tumour xenografts.

The study was conducted to investigate the effects of a novel therapeutic approach, i.e. the combination of chemotherapy and immunotherapy, against a human prostate carcinoma xenograft. A topoisomerase I inhibitor, topotecan, and CpG-containing oligodeoxynucleotides (CpG-ODN) were combined. Athymic mice bearing the PC-3 human prostate carcinoma were treated with the maximum tolerated dose (MTD) of topotecan (3 weekly treatments) and with repeated treatments of CpG-ODN (40 and 20 microg/mouse); tumour growth and lethal toxicity were monitored. Topotecan effect on CpG-ODN-induced production of interleukin (IL) 12, interferon (IFN)-gamma and tumour necrosis factor-alpha was also assessed. Since topotecan pretreatment differentially influenced CpG-ODN-induced production of IL-12 and IFN-gamma, the antitumour effects of the two therapies were investigated in a sequential (full topotecan regimen followed by CpG-ODN) or in an alternating sequence (starting with CpG-ODN). Topotecan inhibited PC-3 tumour growth, inducing 95% tumour volume inhibition. All combined treatments resulted in a significant delay in tumour growth, compared to the effects in topotecan-treated mice (P<0.01, by analysis of tumour growth curves). The combination regimens were well tolerated, except for the alternating sequence of 40 microg CpG-ODN and topotecan, which resulted in three out of eight toxic deaths. This alternating sequence was highly toxic even when another cytotoxic drug (doxorubicin) was used in healthy mice. In conclusion, the combination of topotecan and CpG-ODN increased antitumour effects over chemotherapy alone in the growth of a human prostate carcinoma xenograft. Administration sequence was critical to the combination toxicity: the complete regimen of the cytotoxic drug followed by repeated administrations of the immunomodulator seemed the most promising for further investigations.

Innate immunity in breast carcinoma.

The innate immune response, which depends on so-called pattern-recognition receptors (PRRs) is an evolutionarily old immune response able to elicit a defensive response against a vast array of pathogens. The purpose of this review is to revisit the role of innate immunity in breast carcinoma from the oldest therapeutic approach using bacillus Calmette-Guerin to the recent findings on the manipulation of the PRR pathways with unmethylated cytosine-guanosine dinucleotides (CpG motifs). Encouraging results have been obtained in prevention and local treatment of murine mammary tumors using tumor cells engineered to express stably mycobacterial antigens or directly using CpG-containing oligonucleotides. The experimental findings raise the possibility of successful anti-tumor management through stimulation of innate immunity in women at high risk of developing breast cancer and in breast cancer patients with reasonable immunological performance and low tumor load.

Role of hormonal risk factors in HER2-positive breast carcinomas.

Examination of parity, age at menarche and at menopause by HER2 status in a large series of breast carcinomas showed a statistically significant increased-frequency of HER2-positive tumours in lower risk subgroups. The findings suggest a difference in the protective role of hormone-related risk factors between HER2-positive and -negative tumours.

Topical administration of a doxorubicin-specific monoclonal antibody prevents drug-induced mouth apoptosis in mice.

One of the most severe side effects of anti-tumour chemotherapy is mucositis due to drug toxicity for rapidly dividing cells. We show here that anti-DXR monoclonal antibodies can prevent DXR-induced damage. Indeed, apoptosis, confined to the proliferative compartment of the basal mucosa, observed in the tongue of DXR-treated mice was completely inhibited by topical application of the anti-DXR antibodies.

HER2 as a prognostic factor in breast cancer.

HER2 amplification/overexpression is a marker of poor prognosis in breast cancer. The prognostic impact of HER2 positivity is lower in node-negative compared with node-positive women. The only significant, independent prognostic factors in breast cancer are node status, HER2 status and menopausal status. HER2-positive tumors also contain p53 abnormalities, tend to be hormone receptor and bcl-2 negative, have lymphoid infiltration (LI) and a high mitotic index. Patients with LI who are HER2 positive have a better prognosis than those who are HER2 negative, whereas HER2-positive patients without LI have a significantly worse prognosis than HER2-negative patients. Morphological and biological alterations appear to identify two categories of breast tumor. Two hypotheses may explain the progression to two tumor types: (1) atypical ductal hyperplasia (ADH) is a precursor of ductal carcinoma in situ (DCIS), which is a precursor of invasive ductal carcinoma (IDC); or (2) ADH is a precursor of HER2-negative IDC whereas DCIS is a precursor of HER2-positive IDC. The second theory fits well with two breast cancer subsets and the characteristics of ADH and DCIS. The first type of IDC occurs in older patients, progresses slowly due to estrogen dependency but is aggressive long term. The other type progresses rapidly, is HER2 positive and is more likely to occur in young patients.

CD11b expression identifies CD8+CD28+ T lymphocytes with phenotype and function of both naive/memory and effector cells.

A previously unreported CD8(+)CD28(+)CD11b(+) T cell subset occurs in healthy individuals and expands in patients suffering from primary viral infections. In functional terms, these cells share the features of naive/memory CD8(+)CD28(+)CD11b(-) and terminally differentiated effector CD8(+)CD28(-)CD11b(+) subpopulations. Like CD28(-) cells, CD28(+)CD11b(+) lymphocytes have the ability to produce IFN-gamma, to express perforin granules in vivo, and to exert a potent cytolytic activity. Moreover, these cells can respond to chemotactic stimuli and can efficiently cross the endothelial barrier. In contrast, like their CD11b(-) counterpart, they still produce IL-2 and retain the ability to proliferate following mitogenic stimuli. The same CD28(+)CD11b(+) subpopulation detected in vivo could be generated by culturing naive CD28(+)CD11b(-) cells in the presence of mitogenic stimuli following the acquisition of a CD45RO(+) memory phenotype. Considering both phenotypic and functional properties, we argue that this subset may therefore constitute an intermediate phenotype in the process of CD8(+) T cell differentiation and that the CD11b marker expression can distinguish between memory- and effector-type T cells in the human CD8(+)CD28(+) T cell subset.

Expansion of rare CD8+ CD28- CD11b- T cells with impaired effector functions in HIV-1-infected patients.

The decline in the number of CD4+ T cells in HIV-1-infected patients is known to be related to the increased number of CD8+CD28- T cells. In this paper, we show that CD8+CD28- T cells from HIV-positive patients have an impaired capability to interact with human endothelial cells. This is due to the dramatic expansion, within this subset, of rare CD11b- cells lacking cell-cell adhesion functions. In 50 HIV-positive patients, 19.5% +/- 6.5% of all T cells were CD8+CD28-CD11b-, whereas only 0.8% +/- 0.4% of all T cells from healthy donors showed this uncommon phenotype. The percentage of circulating CD8+CD28-CD11b- T cells was strongly related to the percentage of CD4+ T cells (r = -0.82). This population is peculiar in terms of HIV infection and was found to possess some characteristics associated with effector functions but its cytotoxic properties were impaired. The percentage of target cells lysed by CD8+CD28-CD11b- was significantly lower than that of cells lysed by its CD11b- counterpart (p <.05) both at low (5:1) or at relatively high (20:1) effector/target ratios. CD8+CD28-CD11b- T cells, which lack the ability to interact with endothelial cells, are likely to accumulate and persist in circulation. The biologic properties of CD8+CD28-CD11b- T cells suggest that these cells might be endstage or aberrant differentiated effector cells. Lack of cell-cell adhesion and impaired cytolytic functions favor the hypothesis of a role for CD8+CD28-CD11b- T cells in the development of immunodeficiency.

Cooperative effects of Mycobacterium tuberculosis Ag38 gene transduction and interleukin 12 in vaccination against spontaneous tumor development in proto-neu transgenic mice.

An approach to stimulating an immune response against tumors is to transduce tumor cells with bacterial genes, which represent a "danger signal" and can induce a wide immune response. Mycobacterium tuberculosis genes and their encoded proteins play a pivotal role in linking innate and cell-mediated adaptive immunity and represent ideal candidates as immune adjuvants for tumor vaccines. The efficacy of a cancer vaccine, obtained by transduction of a mammary tumor cell line with the M. tuberculosis Ag38 gene, was investigated in female mice transgenically expressing the rat HER-2/neu proto-oncogene. These mice spontaneously develop stochastic mammary tumors after a long latency period. The onset of spontaneous mammary tumors was significantly delayed in mice vaccinated with Ag38-transduced cells but not in mice vaccinated with nontransduced cells as compared with untreated mice. Protection from spontaneous tumor development was increased when mice were vaccinated with the mycobacterium gene-transduced vaccine plus a systemic administration of interleukin 12 (IL-12) at a low dose. Mice vaccinated with nontransduced cells plus IL-12 developed tumors, with only a slight delay in tumor appearance as compared with the control group. Lymphocytes obtained from lymph nodes of mice vaccinated with transduced cells secreted high levels of IFN-gamma. CD3+CD8+ spleen cells derived from these mice responded to the tumor with IFN-gamma production. These data indicate the efficacy of a short-term protocol of vaccinations exploiting the adjuvant potency of a M. tuberculosis gene and low doses of IL-12 in a model of stochastic development of mammary tumors. This adjuvant approach may represent a promising immunotherapeutic strategy for cancer immunization.