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Reply to the letter by Tartarone A., Romano G., Iodice G., Capobianco A., Di Renzo N. “The predictive role of HER2-overexpression in early breast cancer”
No full textCorrelation between tumor vascularity, vascular endothelial growth factor production by tumor cells, serum vascular endothelial growth factor levels, and serum angiogenic activity in patients with breast carcinoma
No full textAngiogenesis is an important prognostic factor in invasive breast carcinoma. We analyzed sera and tumor samples from 36 patients with primary breast carcinomas to determine the relationship between tumor vascularity, vascular endothelial growth factor (VEGF) production by tumor cells, levels of circulating VEGF (measured by ELISA assay), and levels of endothelial growth factors analyzed by a functional test of human umbilical vein endothelial cells (HUVEC) proliferation. Tumor vascularity was correlated directly with VEGF production by the tumor, indicating that VEGF production is a relevant factor in determining angiogenesis in primary tumor. No correlation was found either between the number of vessels in the tumor or the production of VEGF by tumor cells and the levels of serum angiogenic factors including VEGF. On the contrary, the two serum tests correlated together because a high serum level of VEGF is more frequent in cases with the presence of HUVEC-stimulating growth factors. These data indicate that the principal source of factors stimulating angiogenesis in the primary tumor is the tumor itself. This is an important issue in the context of anti- angiogenic therapeutic approaches, which should be planned to interfere with tumor production of angiogenic factors rather than with circulating angiogenic factors. In conclusion, whereas the vessel count and VEGF production by tumor cells are parameters that give direct information on tumor angiogenesis, long-term follow-up is necessary to determine the clinical significance of the determination of serum HUVEC-stimulating factors in the progression of breast carcinoma
Oral administration of anti-doxorubicin monoclonal antibody prevents chemotherapy-induced gastrointestinal toxicity in mice
No full textGastrointestinal mucositis is a common and painful condition that afflicts a proportion of cancer patients receiving chemotherapeutic drugs including anthracyclines, and it has become the dose-limiting toxicity for a number of chemotherapeutic regimens. The murine monoclonal antibody MAD11 recognizes the anthracycline doxorubicin, and systemic administration of this antibody in mice treated with doxorubicin was found previously to prevent the toxic effects of the drug. The purpose of this study was to determine whether gastrointestinal toxicity associated with doxorubicin can be reduced by oral administration of anti-doxorubicin MAD11 in mice. Our experiments show that orally administered MAD11 antibodies: (a) are essentially not absorbed in the blood circulation since less than 0.5% of protein-associated radioactivity was recovered from blood samples; (b) reduce the extent of doxorubicin-induced apoptosis in murine intestinal crypts, as determined by labeling strand breaks with modified nucleotides in an enzymatic reaction; and (c) reduce the body weight loss in mice treated with 12 mg/kg body weight of doxorubicin and decrease the early mortality in mice treated with 16 mg/kg body weight. This type of treatment may be useful in preventing anthracycline-induced gastrointestinal mucositis in cancer patients
HER2 as a prognostic factor in breast cancer
No full textHER2 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
Protection against doxorubicin-induced alopecia in rats by liposome-entrapped monoclonal antibodies
No full textAlopecia is a common side effect of several anti-cancer drugs, including doxorubicin. Based on our recent observation that a monoclonal antibody (MAD11) directed against this anthracycline inhibits the systemic toxic effect of the drug in mice, we investigated the possibility that MAD11 administered topically might protect against doxorubicin-induced alopecia. In 31 of 45 young rats treated intraperitoneally with doxorubicin, alopecia was completely prevented by topical treatment of the skin with liposome-incorporated anti-doxorubicin monoclonal antibody. This type of treatment might find relevance in preventing anthracycline-induced alopecia in cancer patients. Our findings also provide the first demonstration that liposome-entrapped monoclonal antibodies are capable of penetrating the stratum corneum of the skin without losing their function
The HER2 World: better treatment selection for better outcome
No full textUnderstanding the mechanisms of trastuzumab efficacy and resistance is a step toward optimizing treatment outcome in HER2-positive breast carcinoma patients. Preclinical studies have indicated different trastuzumab antitumor mechanisms, that is, cytostatic inhibition of tumor proliferation, antibody-dependent cell cytotoxicity, and inhibition of HER2-mediated DNA repair. Clinical studies point to the clinical setting dependence of these mechanisms, with antibody-dependent cell cytotoxicity predominating when trastuzumab is used as monotherapy in neoadjuvant and metastatic settings, whereas inhibition of DNA repair predominates in neoadjuvant and adjuvant settings involving concomitant trastuzumab and chemotherapy; in sequential protocols, the antibody appears to act primarily through cytostatic activity by inhibiting HER2-mediated cell proliferation. Because the mechanisms of resistance to trastuzumab likely depend directly on those of its antitumor activity, resistance mechanisms must also be considered with respect to the different clinical settings. Moreover, the response to this reagent should be assessed according to its ability to induce tumor cytotoxic or cytostatic activity
Tumor-necrosis-factor-induced fibroblast growth factor-1 acts as a survival factor in a transformed endothelial cell line
No full textEndothelial cells undergo apoptosis after withdrawal of growth factors, alterations in the extracellular matrix, or exposure to cytokines. Here we report that tumor necrosis factor (TNF)-alpha induces apoptosis of human endothelial cells derived from the umbilical vein in a dose-dependent fashion. Apoptosis is triggered through a pathway that is independent from the levels of Bcl-2. On the contrary, TNF stimulates the growth of spontaneously transformed human umbilical vein endothelial cells. This proliferative effect is mediated through the up-regulation of fibroblast growth factor-1 by TNF. The addition of specific fibroblast growth factor-1 antisense oligonucleotides inhibits TNF-induced fibroblast growth factor-1 expression, thus inhibiting the growth and triggering apoptosis of spontaneously transformed human umbilical vein endothelial cells
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