Preoperative and perioperative chemotherapy with 5-fluorouracil as continuous infusion in operable breast cancer expressing a high proliferation fraction: cytotoxic treatment during the surgical phase

Silicon micro- and nanofabrication for medicine

This manuscript constitutes a review of several innovative biomedical technologies fabricated using the precision and accuracy of silicon micro- and nanofabrication. The technologies to be reviewed are subcutaneous nanochannel drug delivery implants for the continuous tunable zero-order release of therapeutics, multi-stage logic embedded vectors for the targeted systemic distribution of both therapeutic and imaging contrast agents, silicon and porous silicon nanowires for investigating cellular interactions and processes as well as for molecular and drug delivery applications, porous silicon (pSi) as inclusions into biocomposites for tissue engineering, especially as it applies to bone repair and regrowth, and porous silica chips for proteomic profiling. In the case of the biocomposites, the specifically designed pSi inclusions not only add to the structural robustness, but can also promote tissue and bone regrowth, fight infection, and reduce pain by releasing stimulating factors and other therapeutic agents stored within their porous network. The common material thread throughout all of these constructs, silicon and its associated dielectrics (silicon dioxide, silicon nitride, etc.), can be precisely and accurately machined using the same scalable micro- and nanofabrication protocols that are ubiquitous within the semiconductor industry. These techniques lend themselves to the high throughput production of exquisitely defined and monodispersed nanoscale features that should eliminate architectural randomness as a source of experimental variation thereby potentially leading to more rapid clinical translation.

Med1 plays a critical role in the development of tamoxifen resistance

Understanding the molecular pathways that contribute to the development of tamoxifen resistance is a critical research priority as acquired tamoxifen resistance is the principal cause of poor prognosis and death of patients with originally good prognosis hormone-responsive breast tumors. In this report, we provide evidence that Med1, an important subunit of mediator coactivator complex, is spontaneously upregulated during acquired tamoxifen-resistance development potentiating agonist activities of tamoxifen. Phosphorylated Med1 and estrogen receptor (ER) are abundant in tamoxifen-resistant breast cancer cells due to persistent activation of extracellular signal-regulated kinases. Mechanistically, phosphorylated Med1 exhibits nuclear accumulation, increased interaction with ER and higher tamoxifen-induced recruitment to ER-responsive promoters, which is abrogated by inhibition of Med1 phosphorylation. Stable knockdown of Med1 in tamoxifen-resistant cells not only reverses tamoxifen resistance in vitro but also in vivo. Finally, higher expression levels of Med1 in the tumor significantly correlated with tamoxifen resistance in ER-positive breast cancer patients on adjuvant tamoxifen monotherapy. In silico analysis of breast cancer, utilizing published profiling studies showed that Med1 is overexpressed in aggressive subsets. These findings provide what we believe is the first evidence for a critical role for Med1 in tamoxifen resistance and identify this coactivator protein as an essential effector of the tamoxifen-induced breast cancer growth.

A randomized phase II trial comparing preoperative plus perioperative chemotherapy with preoperative chemotherapy in patients with locally advanced breast cancer

The aim of this study was to investigate in a randomized trial the activity of perioperative chemotherapy in patients treated with preoperative chemotherapy for locally advanced breast cancer and to compare it with the preoperative chemotherapy alone. Patients with cT2-3 N0-2 M0 histologically proven breast cancer, with estrogen receptors and progesterone receptors in less than 20% of cells, or with absence of progesterone receptors, received epirubicin 25 mg/m days 1 and 2, cisplatin 60 mg/m day 1, and fluorouracil 200 mg/m daily as continuous infusion. Responding patients were randomized to continue fluorouracil until 2 weeks after surgery (perioperative chemotherapy) or to stop fluorouracil 1 week before surgery. Fifty-eight patients completed six courses of epirubicin, cisplatin and fluorouracil, and were randomized to perioperative chemotherapy (29 patients) or to control (29 patients). The median Ki-67 index remained stable (32-27.5%) in the perioperative chemotherapy arm (P=0.3) and decreased from 55 to 22.5% in the control arm (P=0.01). The rate of pathological complete remission was 41% in both arms (P=1.0). No significant difference in terms of disease-free survival and overall survival was observed between the two arms. Perioperative chemotherapy failed to show an increase in the pathological complete remission rate. A biological effect on Ki-67 expression was demonstrated.

Breast cancer

Breast cancer remains a public-health issue on a global scale. We report new information about the disease from the past 5 years. Early age at first birth, increasing parity, and tamoxifen use are related to long-term lifetime reduction in breast-cancer risk. Ductal carcinomas in situ has been suggested to be renamed ductal intraepithelial neoplasia to emphasise its non-life-threatening nature. An alternative approach, the progenitor/stem cell theory, predicts that only some tumour cells cause cancer progression and that these should be targeted by treatment. Mammography and ultrasonography are still the most effective for women with non-dense and dense breast tissues, respectively. Additionally, MRI, lymphatic mapping, the nipple-sparing mastectomy, partial breast irradiation, neoadjuvant systemic therapy, and adjuvant treatments are promising for subgroups of breast-cancer patients. Although tamoxifen can be offered for endocrine-responsive disease, aromatase inhibitors are increasingly used. Assessment of potential molecular targets is now important in primary diagnosis. Tyrosine-kinase inhibitors and other drugs with anti-angiogenesis properties are currently undergoing preclinical investigations.

Proliferation markers predictive of the pathological response and disease outcome of patients with breast carcinomas treated by anthracycline-based preoperative chemotherapy

The cell proliferation rate has been correlated to the response of breast carcinomas to preoperative chemotherapy (CT) and to disease outcome. However, this parameter is not yet used to select which tumours should be treated with preoperative CT. Furthermore, there is no consensus in the method used to evaluate cell proliferation. In poor prognosis breast carcinomas (PPBCs) treated by intensive preoperative CT, we compared the predictive value of S phase fraction (SPF), mitotic index (MI) and Ki67. We also evaluated the prognostic significance of the variation of the MI after CT. A series of 55 T2-T4N0N1M0 breast carcinomas were treated with 4 cycles of cyclophosphamide, 5-fluorouracil (5-FU) and doxorubicin. SPF was determined by flow cytometry on pre-therapeutic needle aspiration products. MI and Ki67 were evaluated on pre-therapeutic biopsy samples and on the tumours after CT. Fifteen patients (27%) had a pathological complete response (pCR), whereas 40 (73%) had residual disease. All three proliferative markers were found to have predictive value, but this value was higher for MI than for SPF (P = 0.04) and Ki67 (P = 0.03): the rate of pCR was 50% in cases with MI > 17/3.3 mm2, but was only 7% in cases with MI under this threshold (P = 0.0003). A significant decrease of MI (mean 10.97) was observed after CT (P = 0.001). Furthermore, we observed that even for patients with residual tumour, the variation of MI after CT was a prognostic parameter and overall survival. The sequential analysis of MI in breast cancers treated by preoperative CT thus provides a surrogate for predicting long-term outcome.

A two-gene expression ratio predicts clinical outcome in breast cancer patients treated with tamoxifen

Tamoxifen significantly reduces tumor recurrence in certain patients with early-stage estrogen receptor-positive breast cancer, but markers predictive of treatment failure have not been identified. Here, we generated gene expression profiles of hormone receptor-positive primary breast cancers in a set of 60 patients treated with adjuvant tamoxifen monotherapy. An expression signature predictive of disease-free survival was reduced to a two-gene ratio, HOXB13 versus IL17BR, which outperformed existing biomarkers. Ectopic expression of HOXB13 in MCF10A breast epithelial cells enhances motility and invasion in vitro, and its expression is increased in both preinvasive and invasive primary breast cancer. The HOXB13:IL17BR expression ratio may be useful for identifying patients appropriate for alternative therapeutic regimens in early-stage breast cancer.