10 research outputs found

    Differential p53 protein expression in breast cancer fine needle aspirates: the potential for in vivo monitoring

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    Fine needle aspiration (FNA) biopsy is the least invasive method of sampling breast cancer in vivo and provides material for breast cancer diagnosis. FNA has also been used to examine cellular markers to predict and monitor the effects of therapy. The aim of this study was to assess the accuracy of using FNA material compared with resected cancer for Western blotting studies of the p53 pathway, a key to tumour response to radiotherapy and chemotherapy. Paired samples of breast cancer FNAs collected pre-operatively and post-operatively were compared with tissue samples obtained at the time of surgical resection. Western blots were probed for p53 using the antibodies DO12 and DO1, and for levels of downstream proteins p21/WAF1 and p27. The protein extracted by FNA was sufficient for up to 5 Western blot studies. p53 expression and phosphorylation did not differ significantly pre- and post-operatively, indicating that intra-operative manipulation does not affect p53 expression or downstream activation in breast cancer. However, expression of p53, p21 and p27 varied between individual patients suggesting a range of p53 pathway activation in breast cancer. Immunohistochemistry confirmed that the cancer cells accounted for the protein expression detected on Western blots. FNA yields adequate protein for Western blotting studies and could be used as a method to monitor p53 activity in vivo before and during anti-cancer treatment possibly providing early evidence of tumour response to therapy. © 2001 Cancer Research Campaign  http://www.bjcancer.co

    Doxorubicin and vinorelbine act independently via p53 expression and p38 activation respectively in breast cancer cell lines

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    In the treatment of breast cancer, combination chemotherapy is used to overcome drug resistance. Combining doxorubicin and vinorelbine in the treatment of patients with metastatic breast cancer has shown high response rates; even single-agent vinorelbine in patients previously exposed to anthracyclines results in significant remission. Alterations in protein kinase-mediated signal transduction and p53 mutations may play a role in drug resistance with cross-talk between signal transduction and p53 pathways. The aim of this study was to establish the effects of doxorubicin and vinorelbine, as single agents, in combination, and as sequential treatments, on signal transduction and p53 in the breast cancer cell lines MCF-7 and MDA-MB-468. In both cell lines, increased p38 activity was demonstrated following vinorelbine but not doxorubicin treatment, whether vinorelbine was given prior to or simultaneously with doxorubicin. Mitogen-activated protein kinase (MAPK) activity and p53 expression remained unchanged following vinorelbine treatment. Doxorubicin treatment resulted in increased p53 expression, without changes in MAPK or p38 activity. These findings suggest that the effect of doxorubicin and vinorelbine used in combination may be achieved at least in part through distinct mechanisms. This additivism, where doxorubicin acts via p53 expression and vinorelbine through p38 activation, may contribute to the high clinical response rate when the two drugs are used together in the treatment of breast cancer

    Can we Save the rectum by watchful waiting or TransAnal surgery following (chemo)Radiotherapy versus Total mesorectal excision for early REctal Cancer (STAR‐TREC)? Protocol for the international, multicentre, rolling phase II/III partially randomised patient preference trial evaluating long course concurrent chemoradiotherapy versus short course radiotherapy organ preservation approaches

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    International audienceAim: Organ-saving treatment for early-stage rectal cancer can reduce patient-reported side effects compared to standard total mesorectal excision (TME) and preserve quality of life. An optimal strategy for achieving organ preservation and longer-term oncological outcomes are unknown; thus there is a need for high quality trials.Method: Can we Save the rectum by watchful waiting or TransAnal surgery following (chemo)Radiotherapy versus Total mesorectal excision for early REctal Cancer (STAR-TREC) is an international three-arm multicentre, partially randomized controlled trial incorporating an external pilot. In phase III, patients with cT1-3b N0 tumours, ≀40 mm in diameter, who prefer organ preservation are randomized 1:1 between mesorectal long-course chemoradiation versus mesorectal short-course radiotherapy, with selective transanal microsurgery. Patients preferring radical surgery receive TME. STAR-TREC aims to recruit 380 patients to organ preservation and 120 to TME surgery. The primary outcome is the rate of organ preservation at 30 months. Secondary clinician-reported outcomes include acute treatment-related toxicity, rate of non-operative management, non-regrowth pelvic tumour control at 36 months, non-regrowth disease-free survival at 36 months and overall survival at 60 months, and patient-reported toxicity, health-related quality of life at baseline, 12 and 24 months. Exploratory biomarker research uses circulating tumour DNA to predict response and relapse.Discussion: STAR-TREC will prospectively evaluate contrasting therapeutic strategies and implement new measures including a smaller mesorectal target volume, two-step response assessment and non-operative management for complete response. The trial will yield important information to guide routine management of patients with early-stage rectal cancer

    Predictive Factors and Risk Model for Positive Circumferential Resection Margin Rate after Transanal Total Mesorectal Excision in 2653 Patients with Rectal Cancer

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    The aim of this study was to determine the incidence of, and preoperative risk factors for, positive circumferential resection margin (CRM) after transanal total mesorectal excision (TaTME). Background: TaTME has the potential to further reduce the rate of positive CRM for patients with low rectal cancer, thereby improving oncological outcome. Methods: A prospective registry-based study including all cases recorded on the international TaTME registry between July 2014 and January 2018 was performed. Endpoints were the incidence of, and predictive factors for, positive CRM. Univariate and multivariate logistic regressions were performed, and factors for positive CRM were then assessed by formulating a predictive model. Results: In total, 2653 patients undergoing TaTME for rectal cancer were included. The incidence of positive CRM was 107 (4.0%). In multivariate logistic regression analysis, a positive CRM after TaTME was significantly associated with tumors located up to 1 cm from the anorectal junction, anterior tumors, cT4 tumors, extra-mural venous invasion (EMVI), and threatened or involved CRM on baseline MRI (odds ratios 2.09, 1.66, 1.93, 1.94, and 1.72, respectively). The predictive model showed adequate discrimination (area under the receiver-operating characteristic curve >0.70), and predicted a 28% risk of positive CRM if all risk factors were present. Conclusion: Five preoperative tumor-related characteristics had an adverse effect on CRM involvement after TaTME. The predicted risk of positive CRM after TaTME for a specific patient can be calculated preoperatively with the proposed model and may help guide patient selection for optimal treatment and enhance a tailored treatment approach to further optimize oncological outcomes

    Predictive Factors and Risk Model for Positive Circumferential Resection Margin Rate after Transanal Total Mesorectal Excision in 2653 Patients with Rectal Cancer

    No full text
    The aim of this study was to determine the incidence of, and preoperative risk factors for, positive circumferential resection margin (CRM) after transanal total mesorectal excision (TaTME). Background: TaTME has the potential to further reduce the rate of positive CRM for patients with low rectal cancer, thereby improving oncological outcome. Methods: A prospective registry-based study including all cases recorded on the international TaTME registry between July 2014 and January 2018 was performed. Endpoints were the incidence of, and predictive factors for, positive CRM. Univariate and multivariate logistic regressions were performed, and factors for positive CRM were then assessed by formulating a predictive model. Results: In total, 2653 patients undergoing TaTME for rectal cancer were included. The incidence of positive CRM was 107 (4.0%). In multivariate logistic regression analysis, a positive CRM after TaTME was significantly associated with tumors located up to 1 cm from the anorectal junction, anterior tumors, cT4 tumors, extra-mural venous invasion (EMVI), and threatened or involved CRM on baseline MRI (odds ratios 2.09, 1.66, 1.93, 1.94, and 1.72, respectively). The predictive model showed adequate discrimination (area under the receiver-operating characteristic curve >0.70), and predicted a 28% risk of positive CRM if all risk factors were present. Conclusion: Five preoperative tumor-related characteristics had an adverse effect on CRM involvement after TaTME. The predicted risk of positive CRM after TaTME for a specific patient can be calculated preoperatively with the proposed model and may help guide patient selection for optimal treatment and enhance a tailored treatment approach to further optimize oncological outcomes
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