Immunology and immunotherapy in breast cancer

Immuno-oncology is a rapidly developing field in medicine. Drug combination therapies have already been studied in many clinical trials on various tumor types. In recent years, a checkpoint inhibition therapy with monoclonal antibodies targeting PD-1 and its ligand PD-L1 has been developed. Breast cancer had been examined in the field of immune-oncology relatively recently. This review focuses on clinical evidence regarding immune checkpoint inhibition for curative treatment of various breast ca...     

Treatment of older patients with HER2-positive metastatic breast cancer with pertuzumab, trastuzumab, and docetaxel: subgroup analyses from a randomized, double-blind, placebo-controlled phase III trial (CLEOPATRA)

Lysyl oxidase-like 2 (LOXL2) is associated with invasiveness and metastasis in breast cancer. We analyzed the prognostic impact of LOXL2 for breast cancer patients and investigated the role of LOXL2 in breast cancer cell lines. Immunohistochemical study of LOXL2 expression was done in samples from 309 patients. Survival analysis was performed using log-rank test and Cox regression hazard model. After identification of LOXL2 expression in breast cancer cell lines, we performed matrigel invasion and wound-healing assays with LOXL2-silenced cell lines. In the human study, LOXL2 was expressed in 16.2 % of patients. Comparing the LOXL2-positive versus negative groups, there was a significantly higher proportion of estrogen receptor-negative patients (54.0 vs. 37.0 %, respectively; p = 0.029) and triple-negative patients (34.0 vs. 18.0 %; p = 0.022) in the positive group. In multivariate analysis for overall survival and metastasis-free survival, positive LOXL2 was demonstrated as a poor prognostic factor (HR 2.27 and 2.10, respectively). In vitro study indicated that LOXL2 silencing induces a mesenchymal–epithelial transition-like process in basal cell lines (MDA-MB-231 and BT549) associated with decreased invasive and migratory properties. These clinical and preclinical data confirm that higher LOXL2 expression is associated with invasiveness of basal-like breast cancer cells and lower survival of breast cancer patients. Our results suggest the clinical value of LOXL2 as a therapeutic target in breast cancer.     

Effects of neuraminidase on the regulation of erythropoiesis

In this article, we present evidence that sialic acid-containing surface components play a role in the regulation of erythropoiesis. A 1- hr exposure of mouse bone marrow cells to high concentrations of neuraminidase reduced erythroid colony formation. Coculture of 10(6) untreated thymocytes with neuraminidase-treated bone marrow cells restored erythroid colony growth. Neuraminidase-treated thymocytes retained their ability to suppress erythroid colony formation by untreated marrow cells, but lost their ability to enhance erythroid colony formation. Continuous exposure to low concentrations of neuraminidase enhanced erythroid bone marrow cell colony growth in response to a suboptimal dose of erythropoietin.     

Minimal breast cancer. Clinical characteristics and treatment results

Out of 3718 breast cancer patients treated at Petrov Research Institute of Oncology 262 patients [7%] proved to have minimal (less than 1 cm in diameter) form of breast cancer. Treatment of minimal breast cancer provides favorable end-results (5-year survival 91.2%, 10-year survival--79.5%). Nevertheless, minimal forms of breast cancer are also characterized by the ability to regional (in 28.5% of cases) and distant (in 10.3% of cases) metastatic spread. Organ preserving operations (sectoral resection of one block with axillary-subclavicular fat) are often (18.5%) followed by local-regional recurrences of the disease. Application of adjuvant chemotherapy with Thio-TEPA in patients with minimal breast cancer with regional metastases decreases frequency of recurrences and distant metastases by 17.8%.     

Use of 5-fluorouracil to analyze the effect of macrophage inflammatory protein-1 alpha on long-term reconstituting stem cells in vivo

A macrophage-derived inhibitor of early hematopoietic progenitors (colony-forming unit-spleen, CFU-A) called stem cell inhibitor was found to be identical to macrophage inflammatory protein-1 alpha (MIP-1 alpha). We investigated the effect of MIP-1 alpha on the earliest stem cells that sustain long-term hematopoiesis in vivo in a competitive bone marrow repopulation assay. Because long-term reconstituting (LTR) stem cells are normally quiescent, an in vivo model was first developed in which they are triggered to cycle. A first 5-fluorouracil (5-FU) injection was used to eliminate later progenitors, causing the LTR stem cells, which are normally resistant to 5-FU, to enter the cell cycle and become sensitive to a second 5-FU injection administered 5 days later. Human MIP-1 alpha administered from day 0 to 7 was unable to prevent the depletion of the LTR stem cells by the second 5-FU treatment, as observed on day 7 in this model, suggesting that the LTR stem cells were not prevented from being triggered into cycle despite the MIP-1 alpha treatment. However, the MIP-1 alpha protocol used here did substantially decrease the number of more mature hematopoietic progenitors (granulocyte-macrophage colony-forming cells [CFC], burst- forming unit-erythroid, CFCmulti, and preCFCmulti) recovered in the bone marrow shortly after a single 5-FU injection. In vitro, MIP-1 alpha had no inhibitory effect on the ability of these progenitors to form colonies. This study confirms the in vivo inhibitory effect of MIP- 1 alpha on subpopulations of hematopoietic progenitors that are activated in myelodepressed animals. However, MIP-1 alpha had no effect on the long-term reconstituting stem cells in vivo under conditions in which it effectively reduced all later progenitors.     

Evaluation design of a systematic, selective, internet-based, Chlamydia screening implementation in the Netherlands, 2008-2010: implications of first results for the analysis

Background

The unpredictable nature of the potentially devastating impact of 2009 pH1N1 influenza pandemic highlights the need for pandemic preparedness planning, where modeling studies could be most useful for simulations of possible future scenarios.

Methods

A compartmental model with pre-symptomatic and asymptomatic influenza infections is proposed which incorporates age groups as well as intervention measures such as age-specific vaccination, in order to study spread of influenza in a community.

Results

We derive the basic reproduction number and other effective reproduction numbers under various intervention measures. For illustration, we make use of the Pneumonia and Influenza (P&I) mortality data and vaccination data of the very young (age 0-2) and the very old (age >64) during 2004-2005 Taiwan winter influenza season to fit our model and to compute the relevant reproduction numbers. The reproduction number for this winter flu season is estimated to be slightly above one (~1.0001).

Conclusions

Comparatively large errors in fitting the P&I mortality data of the elderly (>64) were observed shortly after winter school closings in January, which may indicate the impact of younger, more active age groups transmitting influenza to other age groups outside of the school settings; in particular, to the elderly in the households. Pre-symptomatic infections seemed to have little effect on the model fit, while asymptomatic infection by asymptomatic infectives has a more pronounced impact on the model fit for the elderly mortality, perhaps indicating a larger role in disease transmission by asymptomatic infection. Simulations indicate that the impact of vaccination on the disease incidence might not be fully revealed in the change (or the lack thereof) in the effective reproduction number with interventions, but could still be substantial. The estimated per contact transmission probability for susceptible elderly is significantly higher than that of any other age group, perhaps highlighting the vulnerability of the elderly due to close contacts with their caretakers from other age groups. The relative impact of targeting the very young and the very old for vaccination was weakened by their relative inactivity, thus giving evidence of the lack of impact of vaccinating these two groups on the overall transmissibility of the disease in the community. This further underscores the need for morbidity-based strategy to prevent elderly mortality.     

Sonoelastography in the diagnosis of breast tumors smaller than 2 cm

This is an analysis of the use of sonoelastography as part of complex instrumental diagnostic procedure (mammography, gray-scale and Doppler ultrasonography) for small breast tumors. A total of 126 patients with breast lesions below 20 mm in diameter were divided into two groups depending on lesion size. The first group consisted of women with 5-10 mm lesions (21 patients with carcinoma and 20 patients with benign tumors), the second group was characterized by 11-20 mm lesions (69 carcinoma patients and 16 patients with benign lesions). According to analysis results the diagnostic complex of gray-scale ultrasonography and sonoelastography is most sensitive, the sensitivity is higher in the second group (89.1% and 97.7% respectively). The complex ultrasonography procedure yielded better overall results than mammography in both patients' groups.     

Relapse in Hodgkin lymphoma

The retrospective study revealed the 15% relapse rate in patients with stage II-IV unfavorable prognosis Hodgkin lymphoma, 5-year OS in relapsed patients was 84%. Karnofsky score less than 80 (p=0,0001), more than 1 extranodal lesion (p=0,0004), extensive (equal to stage III-IV) involvement on relapse (p=0,001), b-symptoms on relapse (p=0,023), more than 5 lymph nodal lesions (p=0,027), albumin level less than 40 g per liter (p=0,037), detection of new nodal lesions (p=0,041) were shown by discriminative analysis as the therapy effect predictors in patients with Hodgkin lymphoma relapse. In patients with second-line therapy failure the actuarial survival rate was lower by 55% in comparison to patients with chemosensitive relapses (40% and 95%). The secondary therapy resistance was shown to be an unfavorable prognosis predictive factor (p=0,0001). The multifactorial overall survival analysis revealed the following adverse prognostic factors: failure of second-line treatment (p=0,0001), first early relapse (p=0,01), albumin level on relapse less than 40 g per liter (p=0,02), use of standard chemotherapy instead of irradiation (p=0,02). The relapse patients with 1 or less risk factors had 95% 5-year OS, the patients with 3 or more adverse risk factors had 70% OS (p=0,0002). The lowest 10-year OS was observed in patients with 2 or more adverse risk factors, 48% and 28% accordingly. Adverse risk factors must be considered while choosing the optimal treatment strategy aimed at better survival rate.     

Effects of fulvestrant 250mg in premenopausal women with oestrogen receptor-positive primary breast cancer

Fulvestrant (Faslodex) reduces markers of hormone sensitivity and proliferation in postmenopausal women. This Phase II double-blind, randomised, multicentre study compared the effects of a single 250mg intramuscular dose of fulvestrant and placebo 14-21 days prior to surgery of curative intent on the oestrogen receptor (ER), progesterone receptor and Ki67 levels in 66 premenopausal women with ER-positive primary breast cancer. There were no statistically significant differences between fulvestrant and placebo with respect to any of the three markers analysed. The most common adverse events in both groups were nausea, headache and pyrexia. Fulvestrant 250mg had no effects on markers of hormone-sensitivity and proliferation in premenopausal women with primary breast cancer when measured at 14-21 days after injection. These findings suggest that a higher fulvestrant dose may be required in this patient population. Further clinical trials are necessary to evaluate the efficacy of fulvestrant in premenopausal women.