Abstract 2684: Inhibition of tumor growth and angiogenesis by SP-2, an anti-LGALS3BP antibody

Background: Accumulating evidence indicates that serum and tissue levels of the lectin galactoside-binding soluble 3 binding protein (LGALS3BP), a secreted glycoprotein, are elevated in human cancer. Recently, we have identified LGALS3BP as a factor capable of stimulating angiogenesis of microvascular endothelial cells in culture as well as in vivo. However, the potential therapeutic implications of LGALS3BP function blockade, has not been explored yet.

Methods: Here we tested the ability of an anti-LGALS3BP monoclonal antibody, named SP-2, to antagonize LGALS3BP-induced angiogenesis and tumor growth.

Results: SP-2 dose-dependently inhibited HUVEC tubulogenesis induced by either conditioned medium of breast cancer and melanoma cells or purified recombinant LGALS3BP. This was accompanied by inhibition of FAK, Akt and ERKs phosphorylation as well as FAK recruitment to membrane sites and actin remodeling. In vivo, SP-2 inhibited LGALS3BP-stimulated angiogenesis and restrained growth of different xenograft models of human cancer. Finally, the combination of SP-2 with low-dose Bevacizumab was more effective than either agent alone in suppressing angiogenesis and tumor growth.

Conclusions: Targeting LGALS3BP with SP-2 could represent a promising therapeutic approach for LGALS3BP expressing tumors.

Citation Format: Enza Piccolo, Sara Trani, Nicola Tinari, Cosmo Rossi, Rossana La Sorda, Rossano Lattanzio, Maurizia D'Egidio, Annalisa Di Risio, Antonino Grassadonia, Francesca Spinella, Anna Bagnato, Mauro Piantelli, Clara Natoli, Stefano Iacobelli. Inhibition of tumor growth and angiogenesis by SP-2, an anti-LGALS3BP antibody. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2684. doi:10.1158/1538-7445.AM2014-2684

Breast cancer "tailored follow-up" in Italian oncology units: a web-based survey

Purpose

Breast cancer follow-up procedures after primary treatment are still a controversial issue. Aim of this study was to investigate, through a web-based survey, surveillance methodologies selected by Italian oncologists in everyday clinical practice.

Methods

Referents of Italian medical oncology units were invited to participate to the study via e-mail through the SurveyMonkey website. Participants were asked how, in their institution, exams of disease staging and follow-up are planned in asymptomatic women and if surveillance continues beyond the 5^th year.

Results

Between February and May 2013, 125 out of 233 (53.6%) invited referents of Italian medical oncology units agreed to participate in the survey. Ninety-seven (77.6%) referents state that modalities of breast cancer follow-up are planned according to the risk of disease progression at diagnosis and only 12 (9.6%) oncology units apply the minimal follow-up procedures according to international guidelines. Minimal follow-up is never applied in high risk asymptomatic women. Ninety-eight (78.4%) oncology units continue follow-up in all patients beyond 5 years.

Conclusions

Our survey shows that 90.4% of participating Italian oncology units declare they do not apply the minimal breast cancer follow-up procedures after primary treatment in asymptomatic women, as suggested by national and international guidelines. Interestingly, about 80.0% of interviewed referents performs the so called “tailored follow-up”, high intensity for high risk, low intensity for low risk patients. There is an urgent need of randomized clinical trials able to determine the effectiveness of risk-based follow-up modalities, their ideal frequency and persistence in time.

Inhibition of tumor growth and angiogenesis by SP-2, an anti-lectin, galactoside-binding soluble 3 binding protein (LGALS3BP) antibody

Accumulating evidence indicates that serum and tissue levels of lectin, galactoside-binding soluble 3 binding protein (LGALS3BP), a secreted glycoprotein, are elevated in human cancers. Recently, we have identified LGALS3BP as a factor capable of stimulating angiogenesis of microvascular endothelial cells in vitro as well as in vivo. However, the potential therapeutic implications of LGALS3BP function blockade have not been explored yet. Here, we tested the ability of an anti-LGALS3BP mouse monoclonal antibody, SP-2, to antagonize LGALS3BP-induced angiogenesis and tumor growth. The antibody was found to inhibit endothelial cell tubulogenesis induced by either conditioned medium of breast cancer and melanoma cells or human recombinant LGALS3BP. In addition, SP-2 inhibited phosphorylation of FAK and its recruitment to membrane sites as well as AKT and ERK phosphorylation promoted by LGALS3BP. When used in vivo, the antibody restrained LGALS3BP-stimulated angiogenesis and growth of tumor xenografts. Furthermore, the combination of SP-2 and low-dose bevacizumab was more effective than either agent alone. Taken together, these results lead to consideration of SP-2 as a promising candidate for LGALS3BP-targeted therapy.

Long-term outcome of neoadjuvant endocrine therapy with aromatase inhibitors in elderly women with hormone receptor-positive breast cancer

Background

Aromatase inhibitors (AIs) are more effective than tamoxifen as neoadjuvant endocrine therapy (NET) for hormone receptor (HR)-positive breast cancer. Here we report the surgical and long-term outcome of elderly postmenopausal patients with locally advanced, HR-positive breast cancer treated with preoperative AIs.

Methods

Between January 2003 and December 2012, 144 postmenopausal patients inoperable with breast conservative surgery (BCS) received letrozole, anastrozole, or exemestane as NET. Patients underwent breast surgery and received adjuvant AIs. Adjuvant systemic therapy, chemotherapy and/or trastuzumab, and adjuvant radiotherapy were administered as appropriate, but limited to high-risk patients with few or no comorbidities.

Results

After a median follow-up of 49 months, 4 (3.0 %) patients had local relapse, 18 (12.5 %) had distant metastases, and 24 (17.0 %) died. BCS was performed in 121 (84.0 %) patients. A tumor size <3 cm and human epidermal growth factor receptor 2 (HER2) negativity were predictors of BCS. The achievement of BCS and grade G1 were significantly associated with longer disease-free survival (DFS) (p = 0.009 and p = 0.01, respectively) and overall survival (p = 0.002 and p = 0.005, respectively). Residual tumor ≤2 cm (yT0–yT1) in the longest diameter after NET was also statistically associated with longer DFS (p = 0.005).

Conclusions

The results of this retrospective study indicate that elderly breast cancer patients with a tumor size <3 cm at diagnosis and HER2 negativity have a higher probability of achieving BCS after NET. Moreover, patients treated with BCS and with grade G1 tumor have a reduced risk of recurrence and death in the long-term follow-up.

Role of Hydroxamate-Based Histone Deacetylase Inhibitors (Hb-HDACIs) in the Treatment of Solid Malignancies

Hydroxamate-based histone deacetylase inhibitors (Hb-HDACIs), such as vorinostat, belinostat and panobinostat, have been previously shown to have a wide range of activity in hematologic malignancies such as cutaneous T-cell lymphoma and multiple myeloma. Recent data show that they synergize with a variety of cytotoxic and molecular targeted agents in many different solid tumors, including breast, prostate, pancreatic, lung and ovarian cancer. Hb-HDACIs have a quite good toxicity profile and are now being tested in phase I and II clinical trials in solid tumors with promising results in selected neoplasms, such as hepatocarcinoma. This review will focus on their clinical activity and safety in patients with advanced solid neoplasms.

Effectiveness and response predictive factors of erlotinib in a non-small cell lung cancer unselected European population previously treated: A retrospective, observational, multicentric study

Aims and background:

Erlotinib approval was supported by the positive results of a large multicentric phase III trial (BR.21 study) that included 10% Asiatic patients and the remaining were North-American Caucasian. It is well-known that the efficacy of tyrosine kinase inhibitors is strongly influenced by ethnicity and other genetic factors. It is, therefore, relevant to establish whether the same profile of efficacy is seen in an unselected population and whether the results of BR.21 can be generalized to other patient populations, such as that described here.

Methods:

In this retrospective, observational, multicentric study, we assessed effectiveness and potentially response predictive factors in 222 unselected Italian patients, with stage IIIB/IV non-small-cell lung cancer, with performance status from 0 to 3, who had received at least one line of chemotherapy, treated with the standard dose of erlotinib (150 mg once daily) until disease progression or unacceptable toxicity.

Results:

The disease control rate was 60.9% (135 patients). Median progression-free survival and overall survival times were 3.1 months and 7.97 months, respectively. The characteristics of non-smoker, female gender, performance status 0 or 1 were associated with a significantly better prognosis in terms of disease control rate and were also predictive of longer overall survival and progression-free survival. The 1-year survival rate was 38.79%. Even though Italian patients baseline characteristics were strongly different to those reported in pivotal BR.21 trial in terms of age, performance status, line treatment and ethnic group, our study confirms the favorable effectiveness profile in real clinical practice of erlotinib according to results from the pivotal study BR.21.

Conclusions:

Today, we know that epidermal growth factor receptor (EGFR) status assessment is mandatory before starting first-line therapy and that the presence of only certain clinical characteristics initially associated with sensitivity to EGFR-tyrosine kinase inhibitors, as reported in this study, is not sufficient in selecting patients candidates to such treatments.

Long-term outcome of neoadjuvant systemic therapy for locally advanced breast cancer in routine clinical practice

PURPOSE

The aim of this study is to evaluate the long-term outcome of patients with locally advanced breast cancer treated with neoadjuvant systemic chemotherapy (NST) in routine clinical practice.

METHODS

Four hundred and nine patients were identified between January 1999 and December 2011. All patients received NST followed by surgery, adjuvant treatments and radiotherapy, as appropriate.

RESULTS

At Kaplan-Meier analysis, patients with surgical stage III disease were more likely to develop distant metastasis and die from breast cancer (p < 0.001). Luminal A and luminal B/HER2-negative patients had better prognosis; moreover, patients with hormone receptor (HR)-positive tumors had a significantly longer DRFS (p < 0.0049) and OS (p < 0.0001) compared with patients with HR-negative tumors as well as patients who underwent breast-conserving surgery (DRFS and OS: p < 0.001). In multivariate analysis, HR negativity (p < 0.001 for both DRFS and OS), mastectomy (DRFS: p = 0.009; OS: p = 0.05) and stage III disease (DRFS: p < 0.001; OS: p = 0.003) were associated with shorter DRFS and OS.

CONCLUSIONS

HR negativity, mastectomy and pathological stage III disease are the variables independently associated with a worse outcome in our cohort of patients. These data are of high interest since they derive from a very heterogeneous group of patients, treated with different neoadjuvant/adjuvant regimens outside of clinical trials and with a long follow-up period.

90k is a serum marker of poor-prognosis in non-hodgkins-lymphoma patients

Monoclonal antibody SP-2, which binds to a 90,000 daltons tumor-associated antigen termed 90K, was generated by mouse immunization with proteins released by human breast cancer cells into the culture medium (Iacobelli et al: Cancer Res 46: 3005-3010, 1986). Elevated 90K levels have been previously reported in the serum of patients with various malignancies. We investigated whether the circulating levels of 90K antigen might be related to prognosis of patients with Non-Hodgkin's Lymphomas (NHL). Serum samples were obtained from 50 apparently healthy blood donors and 81 patients with NHL. Circulating serum 90K concentrations (U/ml) were determined by a solid-phase immunoradiometric assay (IRMA) by a two-step procedure. Serum 90K levels were significantly higher in patients with NHL than in healthy controls (p=0.004). The Kaplan-Meier analysis of overall survival showed that patients with 90K-negative (serum 90K levels less than or equal to 16 U/ml) survived longer than patients with 90K-positive sera (less than or equal to 16 U/ml) (p=0.004). Multivariate regression analysis revealed that serum levels of LDH and 90K were the two independent prognostic variables for predicting overall survival. We propose that an elevated 90K antigen level in sera is a predictor of poor prognosis in NHL.

An epigenetic approach to pancreatic cancer treatment: the prospective role of histone deacetylase inhibitors

Pancreatic ductal adenocarcinoma (PDAC) is quite resistant to conventional treatments, and gemcitabine, the standard chemotherapeutic agent, offers only a small benefit. Development and progression of PDAC are complex processes involving dysregulation of multiple signal transduction pathways arising from not only genetic but also epigenetic alterations. This makes the epigenetic approach to the treatment of PDAC of great interest. Histone deacetylases, a family of enzymes that, by removal of acetyl groups from a variety of histone and nonhistone proteins, play an important role in the epigenetic regulation of gene expression, are frequently dysregulated in PDAC. In particular, overexpression of class I histone deacetylases has been related to higher tumor grade, poor prognosis and development of chemoresistance. Histone deacetylase inhibitors (HDACIs), a novel class of agents endowed with pleiotropic antitumor effects, appear promising either for their preferential toxicity towards transformed as compared to normal cells and their ability to synergistically enhance the anticancer activity of radiotherapy and many chemotherapeutic agents. Many HDACIs have been shown to increase the antiproliferative and proapoptotic effects of gemcitabine, 5-fluorouracil and bortezomib, a new proteasome inhibitor, in vitro and in vivo PDAC xenograft models. MGCD0103, romidepsin, panobinostat, vorinostat and valproic acid, are currently being tested in association with radiotherapy or chemotherapy (gemcitabine, fluoropyrimidines, proteasome inhibitors) in phase I-II clinical trials in patients with locally advanced or metastatic PDAC.

Triplet chemotherapy in patients with metastatic colorectal cancer: toward the best way to safely administer a highly active regimen in clinical practice

A major problem concerning the addition of more drugs in a chemotherapy combination is designing a proper schedule assuring the balance between dose intensity of each drug, efficacy of the combination, and tolerability lessening the burden of drug toxicity. We evaluated triplet chemotherapy-based intensive regimens proposed as first-line treatment in patients with metastatic colorectal cancer. Using a FOLFOXIRI (5-fluorouracil [5-FU], irinotecan, and oxaliplatin) combination regimen, patients with metastatic colorectal cancer now have the possibility of longer survival, but disappointingly, with increased toxicities. Triplet chemotherapy regimen according to 5-fluorouracil, irinotecan /5-fluorouracil, oxaliplatin, characterized by timed flat-infusion 5-FU administration, without leucovorin, obtained efficacy equivalent to other reported similar combination regimens (5-FU, irinotecan, and oxaliplatin), with increased received 5-FU dose intensity and lower grade 3 to 4 neutropenia. To guarantee the proper balance between dose intensities, efficacy, and toxicity, triplet chemotherapy schedules could be further improved by abrogation of folinic acid and bolus 5-FU, a new and easy modality of 5-FU administration, such as timed flat-infusion 5-FU, associated with alternating irinotecan and oxaliplatin; this could favor diffusion of this intensive treatment in clinical practice.

Meta-analysis of phase III trials of docetaxel alone or in combination with chemotherapy in metastatic breast cancer

Purpose

Whether combination chemotherapy offers an advantage over sequential therapy in metastatic breast cancer (MBC) is still an unsettled issue. Polychemotherapy regimens containing taxanes has been shown to increase overall survival (OS), time to tumor progression (TTP), and overall response rate (ORR) when compared with regimens that did not contain a taxanes, while taxane-based doublets have a statistically significant benefit over single-agent taxane only for progression-free survival. However, the term “taxanes” generally includes both paclitaxel and docetaxel, drugs with different clinical activity. Aim of this work is to compare OS, TTP, and ORR in patients with MBC receiving docetaxel alone or in combination with chemotherapy using a formal meta-analysis.

Methods

We performed a systematic review of all published trials comparing docetaxel alone or in combination with other chemotherapeutic agents in MBC.

Results

Three randomized clinical trials including 1,313 patients were retrieved. A significant reduction of risk ratio was found in TTP (P ≤ 0.0001) but not in OS (P = 0.48) or ORR (P = 0.10) for patients treated with a chemotherapy agent plus docetaxel compared with docetaxel alone. Treatment with docetaxel alone is associated with a lower incidence of grade 3 diarrhea and stomatitis (diarrhea, P = 0.011; stomatitis, P = 0.0004).

Conclusion

Combination chemotherapy regimens with docetaxel show a statistically significant advantage for TTP, but not for OS and ORR in MBC. This review confirms that it is unlikely that any single agent or combination chemotherapy regimen will emerge as superior in MBC, due to its heterogeneous nature.

Unknown primary tumors

An unknown primary tumor (UPT) is defined by the presence of a metastatic cancer without a known primary site of origin despite a standardized diagnostic workup. Clinically, UPTs show rapid progression and early dissemination, with signs and symptoms related to the metastatic site. The molecular bases of their biology remain largely unknown, with no evidence as to whether they represent a distinct biological entity. Immunohistochemistry remain the best diagnostic tool in term of cost-effectiveness, but the time-consuming "algorithmic process" it relies on has led to the application of new molecular techniques for the identification of the primary site of UPTs. For example, several microarray or miRNA classifications of UPTs have been used, with an accuracy in the prediction of the primary site as high as 90%. It should be noted that validating a prediction of tissue origin is challenging in these patients, since most of them will never have a primary site identified. Moreover, prospective studies to determine whether selection of treatment options based on such profiling methods actually improves patient outcome are still missing. In the last few years functional imaging (i.e. FDG-PET/CT) has gained a main role in the detection of the site of origin of UPTs and is currently recommended by the European Association of Nuclear Medicine. However, despite recent refinements in the diagnostic workup, the site of origin of UPT often remains elusive. As a consequence, treatment of patients with UPT is still empirical and inadequate.

Tyrosine kinase inhibitors

Over the last ten years, several new and therapeutically relevant cancer drugs targeting tyrosine kinases signaling pathways have been developed. Tyrosine kinase inhibitors (TKIs) are a pharmaceutical class of small molecules, orally available, well-tolerated, worldwide approved drugs for the treatment of several neoplasms, including lung, breast, kidney and pancreatic cancer as well as gastro-intestinal stromal tumors and chronic myeloid leukemia. This comprehensive review focuses on the most relevant members of the first and the second generation TKIs designed to interact with receptor and nonreceptor TKs. Attention is mainly focused on molecular mechanisms in in vitro and in vivo models related to the clinical activity of the drugs and to the development of resistance to treatment, still the major challenge in cancer research and care.

High expression of 90K (Mac-2 BP) is associated with poor survival in node-negative breast cancer patients not receiving adjuvant systemic therapies

90K (Mac-2 BP) expression was evaluated by immunohistochemistry in paraffin-embedded tissue from a consecutive series of lymph-node negative breast cancer patients who did not receive adjuvant systemic treatment. An independent series of patients served as validation set. The association of 90K expression with risk of recurrence and death was examined in survival analyses together with known prognostic factors. High levels of 90K expression (IHC score>8) were observed in 43 (25.3%) of 170 tumors examined. We found elevated risks of distant recurrence and overall mortality in patients with high 90K expression compared with patients with low 90K expression in their tumors. This increase persisted after adjusting for other prognostic factors in multivariate analysis (hazard ratio=4.084; p<0.001 for recurrence; hazard ratio=4.298; p<0.001 for death). These findings were confirmed in the validation set. Therefore, evaluation of 90K expression may be beneficial to identify lymph-node negative breast cancer patients at lower risk of disease recurrence and death.

Synthetic inhibitors of galectin-1 and -3 selectively modulate homotypic cell aggregation and tumor cell apoptosis

BACKGROUND

Galectins have emerged as critical regulators of tumor progression and metastasis, by modulating different biological events including homotypic cell aggregation, apoptosis, migration, angiogenesis and immune escape. Therefore, galectin inhibitors might represent novel therapeutic agents for cancer.

MATERIALS AND METHODS

A series of structural analogs of the disaccharide methyl beta-lactosaminide were screened as potential galectin inhibitors by examining their capability to block binding of galectin-1 and/or galectin-3 to LGalS3BP in solid-phase assays. To demonstrate any functional role in vitro, oligosaccharides were characterized by their ability to regulate tumor cell apoptosis and LGalS3BP-induced homotypic cell aggregation.

RESULTS

Oligosaccharides differentially inhibited binding of each galectin to LGalS3BP. Compounds containing longer oligosaccharide chains were found to be potent inhibitors of both galectins under static conditions. Strikingly, the most active compound in inhibiting homotypic cell aggregation and tumor cell apoptosis was found to be allyl lactoside, which paradoxically exhibited a modest inhibitory capacity for blocking galectin-1 and -3 binding to LGalS3BP.

CONCLUSION

Allyl lactoside represents a novel powerful inhibitor of tumor-associated homotypic cell aggregation and apoptosis. Further investigations are required to remodel selective and potent inhibitors capable of specifically modulating the activity of different members of the galectin family.

Molecular mechanisms of endocrine resistance and their implication in the therapy of breast cancer

The use of endocrine agents is a safe and effective treatment in the management of hormone-sensitive breast cancer. Unfortunately, sooner or later, tumor cells develop resistance to endocrine manipulation making useless this approach. During the last decade, new molecules and intracellular signaling pathways involved in endocrine resistance have been identified. Several studies have documented that estrogen receptor signaling may maintain a pivotal role in the tumor growth despite the failure of a previous hormonal treatment. In this review we will discuss the general principles for optimizing the choice of endocrine therapy based on an understanding of the molecular mechanisms responsible for resistance to the different anti-hormonal agents.

Dynamics of cell cycle phase perturbations by trabectedin (ET-743) in nucleotide excision repair (NER)-deficient and NER-proficient cells, unravelled by a novel mathematical simulation approach

OBJECTIVES

Trabectedin (ET-743, Yondelis) is a natural marine product, with antitumour activity, currently in phase II/III clinical trials. Previous studies have shown that cells hypersensitive to ultraviolet (UV)-rays because of nucleotide excision repair (NER) deficiency, were resistant to trabectedin. The purpose of this study was to investigate whether this resistance was associated with different drug-induced cell cycle perturbations.

MATERIALS AND METHODS

An isogenic NER-proficient cellular system (CHO-AA8) and a NER-deficient one (CHO-UV-96), lacking functional ERCC-1, were studied. Flow cytometric assays showed progressive accumulation of cells in G2 + M phase in NER-proficient but not in NER-deficient cells. Applying a computer simulation method, we realized that the dynamics of the cell cycle perturbations in all phases were complex.

RESULTS

Cells exposed to trabectedin during G1 and G2 + M first experienced a G1 block, while those exposed in S phase were delayed in S and G2 + M phases but eventually divided. In the presence of functional NER, exit from the G1 block was faster; then, cells progressed slowly through S phase and were subsequently blocked in G2 + M phase. This G2 + M processing of trabectedin-induced damage in NER-proficient cells was unable to restore cell cycling, suggesting a difficulty in repairing the damage.

CONCLUSIONS

This might be due either to important damage left unrepaired by previous G1 repair, or that NER activity itself caused DNA damage, or both. We speculate that in UV-96 cells repair mechanisms other than NER are activated both in G1 and G2 + M phases.

A phase II study of dose-dense epirubicin plus cyclophosphamide followed by docetaxel plus capecitabine and pegfilgrastim support as preoperative therapy for patients with stage II, IIIA breast cancer

BACKGROUND

This phase II study was conducted to evaluate tumor response rate and safety profile of dose-dense epirubicin plus cyclophosphamide followed by docetaxel plus capecitabine given preoperatively to patients with stage II or IIIA breast cancer.

PATIENTS AND METHODS

Patients underwent four cycles of dose-dense cyclophosphamide 600 mg/m(2) and epirubicin 90 mg/m(2) every 2 weeks followed by two cycles of docetaxel 36 mg/m(2) on days 1, 8, and 15 plus capecitabine 1250 mg/m(2) on days 5-18 every 4 weeks, with prophylactic pegfilgrastim. The primary objective of the study was to determine the incidence of pathologic complete response defined as the absence of invasive or in situ cancer in the breast and the axillary nodes at definitive surgery.

RESULTS

Forty-four patients were enrolled in the study and 41 (93%) were assessable for response to chemotherapy. An objective clinical response was observed in 38 (93%) patients. Seven patients (17.1%) exhibited a pathologic complete response. Breast-conserving surgery was carried out in 36 (88%) patients. Grade 3/4 neutropenia occurred in 4.3% of 252 administered chemotherapy cycles. No febrile neutropenia, cardiac toxicity, thrombocytopenia or other serious adverse event was registered.

CONCLUSION

The sequential combination of dose-dense epirubicin plus cyclophosphamide followed by docetaxel plus capecitabine is an effective and well-tolerated neo-adjuvant chemotherapy for stage II, IIIA breast cancer.