Overexpression of Sp1 transcription factor induces apoptosis.

Transcription factor Sp1 has recently been shown to be overexpressed in a number of human cancers and its overexpression contributes to malignant transformation. Sp1 regulates the expression of a number of genes participating in multiple aspects of tumorigenesis such as angiogenesis, cell growth and apoptosis resistance. To better understand the role of increased Sp1 levels on apoptosis regulation we have used retroviruses to overexpress this protein in haematopoietic Baf-3 cells and in 3T3 fibroblasts. We have also used inducible expression systems to control ectopic Sp1 levels in different cell types. Surprisingly, Sp1 overexpression on its own induces apoptosis in all the cellular models tested. The apoptotic pathways induced by Sp1 overexpression are cell type specific. Finally, using a truncated form of Sp1, we show that Sp1-induced apoptosis requires its DNA-binding domain. Our results highlight that Sp1 levels in untransformed cells must be tightly regulated as Sp1 overexpression leads to the induction of apoptosis. Our results also suggest that cancer cells overexpressing Sp1 can avoid Sp1-induced apoptosis.

Possibility of conservative local treatment after combined chemotherapy and preoperative irradiation for locally advanced noninflammatory breast cancer.

PURPOSE: The aims of this prospective study were to evaluate the outcome and the possibility of breast conservation therapy for patients with locally advanced noninflammatory breast cancer after primary chemotherapy followed by external preoperative irradiation. METHODS AND MATERIALS: Between April 1982 and June 1990, 97 patients with locally advanced nonmetastatic and noninflammatory breast cancer were treated. The median follow-up was 93 months from the beginning of treatment. The induction treatment consisted of four courses of chemotherapy (doxorubicin, vincristine, cyclophosphamide, 5-fluorouracil) followed by preoperative irradiation (45 Gy to the breast and nodal areas). A fifth course of chemotherapy was given after irradiation therapy. Three different loco-regional approaches were proposed, depending on the tumoral response. In 37 patients (38%) with residual tumor larger than 3 cm in diameter or located behind the nipple or with bifocal tumors, mastectomy and axillary dissection were performed. Sixty other patients (62%) benefited from conservative treatment: 33 patients (34%) achieved complete remission and no surgery was done but additional radiation boost was given to the initial tumor bed; 27 patients (28%) who had a residual mass less than or equal to 3 cm in diameter were treated by wide excision and axillary dissection followed by a boost to the excision site. After completion of local therapy, all patients received a sixth course of chemotherapy. A maintenance adjuvant chemotherapy regimen without anthracycline was prescribed (12 monthly cycles). RESULTS: The 5-year actuarial loco-regional relapse rate was 16% after radiotherapy alone, 16% following wide excision and radiotherapy, and 5.4% following mastectomy. The 5-year loco-regional relapse rate was significantly higher after conservative local treatment (wide excision and radiotherapy, and radiotherapy alone) than after mastectomy (p= 0.04). After conservative local treatment, the 5-year breast conserving rate of patients with loco-regional disease-free status was 84%. For all patients included in this study, the 5-year breast-conserving rate of those who were loco-regional disease-free was 52%. In multivariate analysis, the possibility of breast conservative treatment was significantly related to the initial tumor size and age (more conservative treatment for tumor size < 6cm and age < 50 years). Five- and 10-year overall survival rates and disease-free survival rates were 80, 69, 73, and 61% respectively. Five- and 10-year overall survival rates were not influenced by the local treatment (conservative vs. nonconservative local treatment, p = 0.9). On the other hand, local failure significantly decreased the 5- and 10-year overall survival rates (p , 0.0001). In multivariate analysis, three factors had a significant impact on overall survival and disease-free survival: tumor response after induction chemotherapy, initial tumor size, and clinical stage. Arm lymphedema was noted in 12.5% (8 out of 64) of the patients treated with axillary dissection and in 3% (1 out of 33) without axillary dissection. Cosmetic results were satisfactory in 79% of patients after wide excision and radiotherapy and in 71% of patients treated by radiotherapy alone. CONCLUSIONS: Induction chemotherapy followed by preoperative irradiation may permit the selection of some patients with locally advanced breast cancer for conservative treatment. However, the impact of this treatment modality on long-term survival remains to be established.

Primary chemotherapy and preoperative irradiation for patients with stage II larger than 3 cm or locally advanced non-inflammatory breast cancer.

BACKGROUND AND PURPOSE: To evaluate possibility of breast-conserving therapy and outcome for patients with locally advanced non-inflammatory breast cancer (LABC) and stage II >3 cm in diameter after primary chemotherapy (CT) followed by external preoperative irradiation (RT). MATERIALS AND METHODS: Between 1982 and 1990, 147 patients were treated by four courses of induction CT (doxorubicin, vincristine, cyclophosphamide, 5-fluorouracil) followed by preoperative RT (45 Gy to the breast and nodal areas) and a fifth course of CT. Three different loco-regional approaches were proposed depending on tumour characteristics and tumour response. After completion of local therapy, all patients received a sixth course of CT and a maintenance adjuvant CT regimen without anthracycline. RESULTS: Mastectomy and axillary dissection were performed in 52 patients, and conservative treatment in 95 patients (48 achieved complete remission and received additional radiation boost to initial tumour bed; 47 had a residual mass < or =3 cm in diameter and were treated by wide excision and axillary dissection followed by a boost to the excision site. Ten-year actuarial loco-regional failure rate was 20% after RT alone, 23% after wide excision and RT and 6% after mastectomy (P = 0.85). After multivariate analysis, possibility of breast-conserving therapy was related to initial tumour size. Ten-year overall survival rate was 66%; it was not influenced by local treatment (conservative vs. non-conservative local treatment, P = 0.89). However, local failure significantly decreased overall survival (P < 0.0001). After multivariate analysis, tumour response after induction CT and clinical stage had a significant impact on survival. CONCLUSIONS: The present data indicate that induction CT followed by preoperative RT may permit the selection of some patients with LABC or stage II >3 cm for conservative treatment. The impact of this treatment modality on long term survival remains to be established.

Uterine sarcomas: the Curie Institut experience. Prognosis factors and adjuvant treatments.

PURPOSE: With a retrospective study at a single institution, we propose to analyze the prognosis factors and adjuvant treatment for uterine sarcomas. MATERIALS AND METHODS: From 1975 to 1995, 73 uterine sarcomas were treated at the Institut Curie, corresponding to 61 T1, 5 T2, and 8 T4 tumors. Thirteen patients had metastatic disease at the time of diagnosis. The mean age was 58 years. In 71% of patients, the presenting sign was bleeding. This series consisted of 44% leiomyosarcomas (LMS), 19% endometrial stromal sarcomas (ESS), and 31% carcinosarcomas or mixed mesodermal sarcomas (MMS). For the grading classification, we used the classification of the Sarcoma Group of the French Federation of Cancer Centres for soft tissue sarcomas. Of the patients, 66% presented a high-grade tumor. RESULTS: The median overall survival was 42 months, with a 5-year survival of 45%. Histological grade, FIGO stage, histology types, and menopausal status were the four independent factors in multivariate analysis. Eighteen patients relapsed locally (25.7%), with 77% central pelvic sites. Patients with radiotherapy and ESS had better local control in multivariate analysis. Thirty-four patients developed metastases (48.6%), mainly pulmonary (58.8%). Eight patients presented with peritoneal disease. High grades and LMS had the worst survival without metastasis in multivariate analysis. CONCLUSION: This study validated our classification for sarcoma grading and confirmed the finding of worst prognosis for LMS and the importance of radiotherapy in local control.