Zsuzsanna Kahán

Antagonists of growth hormone-releasing hormone arrest the growth of MDA-MB-468 estrogen-independent human breast cancers in nude mice

Since antagonists of growth hormone-releasing hormone (GH-RH) inhibit proliferation of various tumors, in this study we investigated the effects of GH-RH antagonists MZ-5-156 or JV-1-36 on growth of estrogen-independent MDA-MB-468 human breast cancers xenografted into nude mice. Both GH-RH antagonists administered at a dose of 20 μg/day induced regression of some and growth-arrest of other tumors, while control tumors continued to grow. After 5 weeks of therapy with MZ-5-156 or JV-1-36, final volume and weight of MDA-MB-468 tumors were significantly decreased (all p values <0.001) and serum IGF-I levels as well as tumor IGF-I mRNA expression were reduced as compared with controls. High affinity binding sites for IGF-I were detected by the ligand binding method. Gene expression of human IGF-I receptors, as measured by the RT-PCR, was not significantly different in control and treated MDA-MB-468 tumors. In cell culture, IGF-I did not stimulate, GH-RH slightly stimulated, while MZ-5-156 and JV-1-36 inhibited proliferation of MDA-MB-468 cells known to possess defective insulin and IGF-I receptor signaling. The expression of mRNA for human GH-RH was found in five of 8 tumors treated with GH-RH antagonists, and in one of the five control tumors. These results suggest that GH-RH antagonists inhibit MDA-MB-468 breast cancers possibly through mechanisms involving interference with locally produced GH-RH.

Bevacizumab plus paclitaxel versus bevacizumab plus capecitabine as first-line treatment for HER2-negative metastatic breast cancer: interim efficacy results of the randomised, open-label, non-inferiority, phase 3 TURANDOT trial

BACKGROUND Randomised phase 3 trials in metastatic breast cancer have shown that combining bevacizumab with either paclitaxel or capecitabine significantly improves progression-free survival and response rate compared with chemotherapy alone but the relative efficacy of bevacizumab plus paclitaxel versus bevacizumab plus capecitabine has not been investigated. We compared the efficacy of the two regimens. METHODS In this open-label, non-inferiority, phase 3 trial, patients with HER2-negative metastatic breast cancer who had received no chemotherapy for advanced disease were randomised (by computer-generated sequence; 1:1 ratio; block size six; stratified by hormone receptor status, country, and menopausal status) to receive either intravenous bevacizumab (10 mg/kg on days 1 and 15) plus intravenous paclitaxel (90 mg/m(2) on days 1, 8, and 15) repeated every 4 weeks (paclitaxel group) or intravenous bevacizumab (15 mg/kg on day 1) plus oral capecitabine (1000 mg/m(2) twice daily on days 1-14) repeated every 3 weeks (capecitabine group) until disease progression or unacceptable toxic effects. Treatment allocation was not masked because of the differences in routes of administration and cycle lengths. The primary objective was to show non-inferior overall survival with bevacizumab plus capecitabine versus bevacizumab plus paclitaxel. We report results of an interim overall survival analysis, which was planned for after 175 deaths in the per-protocol population. This trial is registered with ClinicalTrials.gov, number NCT00600340. FINDINGS Between Sept 10, 2008, and Aug 30, 2010, we randomised 564 patients (paclitaxel group n=285; capecitabine group n=279) from 51 centres in 12 countries. The per-protocol population consisted of 533 patients (paclitaxel group n=268; capecitabine group n=265). After median follow-up of 18·6 months (IQR 14·9-24·7), 181 patients in the per-protocol population had died (89 [33%] in the paclitaxel group; 92 [35%] in the capecitabine group). The hazard ratio [HR] for overall survival was 1·04 (97·5% repeated CI -∞ to 1·69; p=0·059); the non-inferiority criterion of the interim analysis (interim α=0·00105) was not met. More patients who received bevacizumab plus paclitaxel had an objective response than did those who received bevacizumab plus capecitabine (125 [44%] of 285 patients vs 76 [27%] of 279; p<0·0001). Similarly, progression-free survival was significantly longer in the paclitaxel group than in the capecitabine group (median progression-free survival 11·0 months [95% CI 10·4-12·9] vs 8·1 months [7·1-9·2]; HR 1·36 [95% CI 1·09-1·68], p=0·0052). The most common adverse events of grade 3 or higher were neutropenia (51 [18%]), peripheral neuropathy (39 [14%]), and leucopenia (20 [7%]) in the paclitaxel group and hand-foot syndrome (44 [16%]), hypertension (16 [6%]), and diarrhoea (15 [5%]) in the capecitabine group. One treatment-related death occurred in the paclitaxel group; no deaths in the capecitabine group were deemed to be treatment-related. INTERPRETATION In this planned interim analysis, the non-inferiority criterion was not met and overall survival results are inconclusive. Final results are expected in 2014. Progression-free survival was better, and more patients achieved an objective response, with bevacizumab plus paclitaxel than with bevacizumab plus capecitabine. Efficacy results in both groups were consistent with previous reports. FUNDING Central European Cooperative Oncology Group; Roche.

Gemcitabine, Epirubicin, and Paclitaxel Versus Fluorouracil, Epirubicin, and Cyclophosphamide As First-Line Chemotherapy in Metastatic Breast Cancer: A Central European Cooperative Oncology Group International, Multicenter, Prospective, Randomized Phase III Trial

BACKGROUND The objectives of this phase III trial were to compare the time to progressive disease (TtPD), overall response rate (ORR), overall survival, and toxicity of gemcitabine, epirubicin, and paclitaxel (GET) versus fluorouracil (FU), epirubicin, and cyclophosphamide (FEC) as first-line therapy in patients with metastatic breast cancer (MBC). PATIENTS AND METHODS Female patients aged 18 to 75 years with stage IV and measurable MBC were enrolled and randomly assigned to either gemcitabine (1,000 mg/m(2), days 1 and 4), epirubicin (90 mg/m(2), day 1), and paclitaxel (175 mg/m(2), day 1) or FU (500 mg/m(2), day 1), epirubicin (90 mg/m(2), day 1), and cyclophosphamide (500 mg/m(2), day 1). Both regimens were administered every 21 days for a maximum of eight cycles. RESULTS Between October 1999 and November 2002, 259 patients (GET, n = 124; FEC, n = 135) were enrolled. Baseline characteristics were well balanced across treatment arms. After a median of 20.4 months of follow-up, median TtPD was 9.1 months and 9.0 months in the GET and FEC arms, respectively (P = .557). The ORR was 62.3% in the GET arm (n = 114) and 51.2% in the FEC arm (n = 129; P = .093). Grade 3 and 4 toxicities, including neutropenia, thrombocytopenia, anemia, stomatitis, neurosensory toxicity, and allergy, occurred significantly more often in the GET arm. CONCLUSION No significant differences in terms of TtPD and ORR were observed between the two treatment arms. Treatment-related toxicity was higher in the GET arm.

Individual Positioning: A Comparative Study of Adjuvant Breast Radiotherapy in the Prone Versus Supine Position

PURPOSE To study breast radiotherapy in the prone vs. supine positions through dosimetry and clinical implementation. METHODS AND MATERIALS Conformal radiotherapy plans in 61 patients requiring only breast irradiation were developed for both the prone and supine positions. After evaluation of the of the first 20 plan pairs, the patients were irradiated in the prone or supine position in a randomized fashion. These cases were analyzed for repositioning accuracy and skin reactions related to treatment position and patient characteristics. RESULTS The planning target volume covered with 47.5-53.5 Gy in the prone vs. the supine position was 85.1% +/- 4.2% vs. 89.2 +/- 2.2%, respectively (p < 0.0001). Radiation exposure of the ipsilateral lung, expressed in terms of the mean lung dose and the V(20Gy), was dramatically lower in the prone vs. supine position (p < 0.0001), but the doses to the heart did not differ. There was no difference in the need to correct positioning during radiotherapy, but the extent of displacement was significantly higher in the prone vs. supine position (p = 0.021). The repositioning accuracy in the prone position exhibited an improvement over time and did not depend on any patient-related parameters. Significantly more radiodermatitis of Grade 1-2 developed following prone vs. supine irradiation (p = 0.025). CONCLUSIONS Conformal breast radiotherapy is feasible in the prone position. Its primary advantage is the substantially lower radiation dose to the ipsilateral lung. The higher dose inhomogeneity and increased rate of Grade 1-2 skin toxicity, however, may be of concern.

Inhibition of growth of MX-1, MCF-7-MIII and MDA-MB-231 human breast cancer xenografts after administration of a targeted cytotoxic analog of somatostatin, AN-238

Since somatostatin (sst) receptors are expressed in a high percentage of human breast cancers, we studied the effects of a targeted cytotoxic somatostatin analog (AN‐238) formed by linking the highly active doxorubicin (DOX) derivative 2‐pyrrolino‐DOX (AN‐201) to octapeptide RC‐121 (D‐Phe‐Cys‐Tyr‐D‐Trp‐Lys‐Val‐Cys‐Thr‐NH2) in 3 human breast cancer models. The models included estrogen‐independent MDA‐MB‐231 and MX‐1 and estrogen‐sensitive MCF‐7‐MIII tumors. Nude mice bearing xenografts of these cancers were injected i.v. with 250 nmol/kg doses of cytotoxic radical AN‐201, cytotoxic analog AN‐238 or the unconjugated mixture of AN‐201 and sst analog RC‐121. Significant inhibition of growth of MDA‐MB‐231, MX‐1 and MCF‐7‐MIII tumors was observed 1 week after injection of a single dose of cytotoxic analog AN‐238. The volume of MDA‐MB‐231 tumors remained significantly decreased 3 weeks after treatment. The volumes and weights of MCF‐7‐MIII tumors continued to be significantly reduced 60 days after therapy with AN‐238. AN‐238 also caused complete regression of MX‐1 tumors in 5 of 10 animals, which remained tumor‐free 60 days after treatment. In contrast, after treatment with cytotoxic radical AN‐201, MDA‐MB‐231 and MCF‐7‐MIII tumors grew steadily and the regression of MX‐1 tumors was only transitory in most animals. Toxicity of AN‐201 was much greater than that of AN‐238, as measured by animal deaths, loss of body weight and leukopenia. High‐affinity sst receptors and mRNA for both sst2 and sst5 subtypes were found in all 3 tumor lines. Expression of sst receptors was not significantly affected by treatment with AN‐238. Our results indicate that the cytotoxic somatostatin analog AN‐238 efficaciously inhibits growth of human breast cancers expressing sst receptor subtypes 2 and 5. Int. J. Cancer 82:592–598, 1999.

Delays in diagnosis and treatment of breast cancer: a multinational analysis

BACKGROUND Reducing treatment delay improves outcomes in breast cancer. The aim of this study was to determine factors influencing patient- and system-related delays in commencing breast cancer treatment in different countries. METHODS A total of 6588 female breast cancer patients from 12 countries were surveyed. Total delay time was determined as the sum of the patient-related delay time (time between onset of the first symptoms and the first medical visit) and system-related delay time (time between the first medical visit and the start of therapy). RESULTS The average patient-related delay time and total delay time were 4.7 (range: 3.4-6.2) weeks and 14.4 (range: 11.5-29.4) weeks, respectively. Longer patient-related delay times were associated with distrust and disregard, and shorter patient-related delay times were associated with fear of breast cancer, practicing self-examination, higher education level, being employed, having support from friends and family and living in big cities. The average system-related delay time was 11.1 (range: 8.3-24.7) weeks. Cancer diagnosis made by an oncologist versus another physician, higher education level, older age, family history of female cancers and having a breast lump as the first cancer sign were associated with shorter system-related delay times. Longer patient-related delay times and higher levels of distrust and disregard were predictors of longer system-related delay times. CONCLUSIONS The delay in diagnosis and treatment of breast cancer remains a serious problem. Several psychological and behavioural patient attributes strongly determine both patient-related delay time and system-related delay time, but their strength is different in particular countries.

Administration of a targeted cytotoxic analog of luteinizing hormone-releasing hormone inhibits growth of estrogen-independent MDA-MB-231 human breast cancers in nude mice

Receptor targeted chemotherapy is less toxic and more effective than conventional chemotherapy. Receptors for luteinizing hormone-releasing hormone (LH-RH) are found in about 50% of human breast cancers. Highly potent cytotoxic radical 2-pyrrolinodoxorubicin (AN-201) was linked to the agonistic analog [D-Lys6]LH-RH to form cytotoxic LH-RH analog AN-207. We evaluated whether AN-207 could be targeted to the hormone-independent MDA-MB-231 human breast cancers. Nude mice bearing MDA-MB-231 tumors were injected i.v. with 250 nmol/kg doses of cytotoxic radical AN-201, cytotoxic LH-RH analog AN-207, the unconjugated mixture of AN-201 and carrier [D-Lys6]LH-RH, [D-Lys6]LH-RH alone and vehicle (control). The growth of MDA-MB-231 tumors in animals given a single dose of AN-207 was inhibited significantly (p=0.01) for 3 weeks after injection, whereas tumors in all the other groups grew steadily. All cytotoxic compounds produced leukopenia, but the strongest lymphocyte suppression was caused by cytotoxic radical AN-201. Three weeks after treatment, the presence of mRNA for LH-RH receptors was demonstrated by RT-PCR in all the groups and radioreceptor assays demonstrated high-affinity binding sites for LH-RH on tumor cell membranes of control animals and those treated with AN-201, the carrier peptide alone or in combination with AN-201. At this time point binding assays did not reveal the expression of membrane proteins in tumors treated with AN-207, but 60 days after administration of AN-207, high affinity LH-RH binding sites were found again in MDA-MB-231 tumors. These results indicate that cytotoxic LH-RH analog AN-207 could be utilized for receptor targeted chemotherapy of breast cancers expressing receptors for LH-RH.

Complete regression of MX‐1 human breast carcinoma xenografts after targeted chemotherapy with a cytotoxic analog of luteinizing hormone–releasing hormone, AN‐207

Receptors for luteinizing hormone–releasing hormone (LH‐RH) are found in about 50% of human breast carcinomas. A highly potent cytotoxic agent, 2‐pyrrolinodoxorubicin (AN‐201), was linked to the agonist [D‐Lys6]LH‐RH to form a cytotoxic LH‐RH analog, AN‐207, that can be targeted to LH‐RH receptors on breast carcinomas.

Casting-type calcifications on the mammogram suggest a higher probability of early relapse and death among high-risk breast cancer patients

A retrospective analysis of the relation between the presence of casting-type calcifications on the mammogram and the prognosis of breast cancer was performed. The mammographic tumor features and other characteristics (invasive tumor size, histological tumor type, grade, nodal, hormone receptor and HER2 status, presence of lymphovascular invasion) of 55 high-risk breast cancers were studied. After a median follow-up time of 29.1 months, the median relapse-free survival and overall survival times among breast cancer patients with tumors associated with casting calcifications were 26.6 and 29.6 months, respectively. The corresponding parameters among patients with tumors not accompanied by casting calcifications were 54.4 and >58.5 months, respectively. Significant associations were found between the presence of casting calcifications and the risks of relapse (HR = 3.048, 95% CI: 1.116–8.323, p = 0.030) or death (HR = 3.504, 95% CI: 1.074–11.427, p = 0.038). Positive associations were found between casting calcifications and ER/PR negativity (p = 0.015 and p = 0.003, respectively) and HER2 overexpression (p = 0.019). Our findings support the theory that breast tumors associated with casting-type calcifications at mammography comprise a disease entity which exhibits significantly more aggressive behavior and a poorer outcome than do cancers with other mammographic tumor features.

Inhibition of growth of MDA-MB-468 estrogen-independent human breast carcinoma by bombesin/gastrin-releasing peptide antagonists RC-3095 and RC-3940-II.

The growth of breast carcinoma is promoted by autocrine growth factors such as the bombesin (BN)‐like peptides and epidermal growth factor (EGF). The stimulatory action of BN‐like peptides can be blocked by the use of BN/gastrin‐releasing peptide (GRP) antagonists.