Toward checkmate: biology and breast cancer therapy for the new millennium

Obesity and HER 2 overexpression: a common factor for poor prognosis of breast cancer

Background

Both obesity and over-expression of HER II are associated with poor prognosis of breast cancer. In vitro experiments suggest that anti-tumour activity of the anti-obesity drug Orlistat is likely to be due to transcriptional suppression of HER II expression. The overexpression of HER II is also positively correlated with other markers of prognosis of breast cancer such as cathepsin expression.

Hypothesis

The hypothesis we tested was that the obese women with breast cancer might over-express HER II more often than their lean counterparts to account for the poor prognosis.

Patients and methods

One hundred consecutive patients were included in this study. Their body mass indexes were correlated with overexpression of HER II.

Results

There was also no association between oestrogen or progesterone receptor positivity and obesity or HER II over expression in premenopausal or post-menopausal women with breast cancer.

Conclusion

The present study demonstrated that the poor outcome of breast cancer in obese patients is not due to over expression of HER II.

Metal complex SERMs (selective oestrogen receptor modulators). The influence of different metal units on breast cancer cell antiproliferative effects

The selective oestrogen receptor modulator tamoxifen is a leading agent in the adjuvant treatment of breast cancer. Several organometallic moieties have been vectorised with tamoxifen, in order to improve on the latter's antiproliferative properties by the addition of a potentially cytotoxic moiety, and have been evaluated versus both oestrogen receptor positive (MCF7) and oestrogen receptor negative (MDA-MB231) breast cancer cells. For tamoxifen analogues with ((R,R)-trans-1,2-diaminocyclohexane)platinum(II), cyclopentadienyl rhenium tricarbonyl, and ruthenocene tethers, there was no enhancement of the antiproliferative effect on oestrogen receptor positive cells, nor any cytotoxic effect on oestrogen receptor negative cells, while those containing cyclopentadienyl titanium dichloride showed an oestrogenic effect. However, compounds where ferrocene replaces tamoxifen's phenyl ring were strongly cytotoxic against both cell lines. The synthesis and biological results of these compounds is reviewed and placed in the historic context of inorganic compounds in therapy.

Role of superoxide dismutase in individualization of breast cancer radiation therapy protocols

Background: The goal of this study was to introduce a new predictive biomarker assay that might improve a clinical irradiation treatment of malignant diseases. Methods: Thirty-two peripheral blood samples obtained from breast cancer patients were analyzed for superoxide dismutase (SOD) after irradiation with gamma rays (60 Co). SOD was measured in subcellular fractions prepared from unirradiated and irradiated blood samples (McCord and Fridovich). The activity of SOD was measured by the method of Misra and Fridovich and protein concentration by the method of Lowry et al. Results Antioxidant radiation response of patients' blood cells was very variable and specific for each individual. The results indicated that the radiation response during radiotherapy directly depends on the initial state of antioxidant activity in the blood of cancer patients. In the blood samples with high level of SOD activity the irradiation decreased enzymatic activity while in the samples with medium or low level of SOD, the SOD activity was preserved or increased by irradiation with 2 Gy of gamma rays. Conclusion We showed that the modulation of SOD activity in blood cells after irradiation in vitro might be used as predictive biomarker in individualization of therapy protocols.

Trastuzumab: hopes and realities

Despite improvements in care of patients with breast cancer, up to half develop refractory or resistant disease. There is therefore a need for new, modified anticancer therapies with greater effectiveness, tolerability to patients, and tumour specificity. Trastuzumab (Herceptin) is the first clinically available oncogene-targeted therapeutic agent for treatment of solid tumours. Clinical trials in patients positive for HER2 (human epidermal-growth-factor receptor 2) show that trastuzumab is effective and well tolerated; as a single-agent second-line or third-line treatment, the drug produced durable tumour responses. First-line trastuzumab in combination with chemotherapy, particularly paclitaxel, significantly improved time to disease progression, duration of response, and time to treatment failure. Combination therapy resulted in a 25% improvement in overall survival compared with chemotherapy alone. Patients with HER2 gene amplification, high overexpression of HER2 (3+ on immunohisto-chemistry), or both features, obtained the greatest clinical benefit. Trastuzumab is the first monoclonal antibody with efficacy in breast cancer and the first gene-product-targeted therapy to produce a significant survival advantage in this disease. Trastuzumab is likely to find its ultimate role in the adjuvant setting. Its development provides a model for the integration of other gene-targeted therapies into breast-cancer management to improve survival and quality of life.

Biomarkers in Barrett esophagus

Barrett esophagus is a premalignant condition that may progress to adenocarcinoma. The risk of developing cancer has been estimated to be approximately 1 in 250 patient-years of observation; however, there appear to be subsets of patients at much higher risk. Risk stratification has previously been determined by histological identification of dysplasia. Several new biomarkers are being tested to help clinicians better determine the risk of cancer development. Although none of these biomarkers has been proven in a prospective study to predict the onset of cancer, they have been correlated with cancer development. Most of these are factors that have been associated with cancer development in other organs. These include assessment of cell proliferation, expression of cyclooxygenase 2, growth factors and oncogenes, secretory factors, cell cycle proteins, adhesion molecules, and aneuploidy and other genetic abnormalities. In addition to their role as potential cancer biomarkers, these factors have increasingly been reported as surrogate markers to monitor the effectiveness of conservative treatments for Barrett esophagus. In this article, biological markers are reviewed for their relevance in Barrett esophagus. Although most biological markers need to be evaluated further and, for most, prospective follow-up studies are lacking, at present abnormal ploidy status, P16 and P53 gene abnormalities, or allelic losses are the most extensively documented.

Biomarkers in Barrett esophagus

Barrett esophagus is a premalignant condition that may progress to adenocarcinoma. The risk of developing cancer has been estimated to be approximately 1 in 250 patient-years of observation; however, there appear to be subsets of patients at much higher risk. Risk stratification has previously been determined by histological identification of dysplasia. Several new biomarkers are being tested to help clinicians better determine the risk of cancer development. Although none of these biomarkers has been proven in a prospective study to predict the onset of cancer, they have been correlated with cancer development. Most of these are factors that have been associated with cancer development in other organs. These include assessment of cell proliferation, expression of cyclooxygenase 2, growth factors and oncogenes, secretory factors, cell cycle proteins, adhesion molecules, and aneuploidy and other genetic abnormalities. In addition to their role as potential cancer biomarkers, these factors have increasingly been reported as surrogate markers to monitor the effectiveness of conservative treatments for Barrett esophagus. In this article, biological markers are reviewed for their relevance in Barrett esophagus. Although most biological markers need to be evaluated further and, for most, prospective follow-up studies are lacking, at present abnormal ploidy status, P16 and P53 gene abnormalities, or allelic losses are the most extensively documented.

Drug-targeting strategies in cancer therapy

Genetic changes in cell-cycle, apoptotic, and survival pathways cause tumorigenesis, leading to significant phenotypic changes in transformed cells. These changes in the tumor environment - elevated expression of surface proteases, increased angiogenesis and glucuronidase activity - can be taken advantage of to improve the therapeutic index of existing cancer therapies. Targeting cytotoxics to tumor cells by enzymatic activation is a promising strategy for improving chemotherapeutics.

An overview of the management of recurrent breast cancer

Breast cancer recurrence is a potential problem for anyone who is diagnosed with breast cancer. Recurrent breast cancer can manifest both locally and systemically and can cause a variety of symptoms. After a diagnosis is established, treatment and symptom management may include radiation, chemotherapy, surgery and hormone therapy. The confirmation of a recurrent diagnosis may have far-reaching psychological and social implications for the patient. The care of each patient with metastatic disease must be tailored to that individual's needs and will involve the varied skills of the multidisciplinary team. The type of care that is given should be negotiated with each patient, and includes a combination of active treatment and symptom management, with the ultimate aim of ensuring that the patient's quality of life is maintained at an optimum level for as long as possible.