Expression and intracellular processing of chimeric and mutant CFTR molecules.

The cystic fibrosis transmembrane conductance regulator (CFTR) is a cyclic AMP-activated chloride channel comprising two membrane-spanning domains (MSDs), two nucleotide-binding domains (NBDs) and a unique regulatory (R) domain. The most frequent cystic fibrosis (CF) mutation, a deletion of Phe508 in NBD1, results in the retention of the DeltaF508 CFTR in the endoplasmic reticulum, as do many other natural or constructed mutations located within the first NBD. In order to further define the role of NBD1 in CFTR folding and to determine whether the higher frequency of mutations in NBD1 with respect to NBD2 results from its position in the molecule or is related to its primary sequence, we constructed and expressed chimeric CFTRs wherein NBD domains were either exchanged or deleted. Synthesis, maturation and activity of the chimeras were assessed by Western blotting and iodide efflux assay after transient or stable expression in COS-1 or CHO cells respectively. The data showed that deletion of NBD1 prevented transport of CFTR to the cytoplasmic membrane whereas deletion of NBD2 did not impair this process but resulted in an inactive chloride channel. On the other hand, substituting or inverting NBDs in the CFTR molecule impaired its processing. In addition, while the NBD1 R555K mutation is known to partially correct the processing of CFTR DeltaF508 and to increase activity of both wild-type and DeltaF508 individual channels, it showed no positive effect when introduced into the double NBD1 chimera. Taken together, these observations suggest that the proper folding process of CFTR results from complex interactions between NBDs and their surrounding domains (MSDs and/or R domain).

[Results of the conservative surgical and irradiation treatment of 132 nonpalpable ductal carcinomas in situ of the breast]. / Résultats du traitement par chirurgie conservatrice et irradiation de 132 carcinomes canalaires in situ non palpables du sein.

PURPOSE: Retrospective analysis of results of treatment of 132 subclinical ductal carcinomas in situ, non-palpable. MATERIAL AND METHODS: Patients were treated with limited surgery and 70 Gy radiation therapy (70 Gy). RESULTS: With a median follow-up of 7 years, the total recurrence rate was 6%, and the actuarial rate at 5 years 4% and at 10 years 13% at. These have no influence on recurrence on the specific actuarial survival rate which was 100% at 10 years. In spite of five infiltrating recurrences of seven, no metastasis appeared 48 months after the salvage surgery. The global rate of breast preservation was 92% at 7 years. DISCUSSION AND CONCLUSION: Therapeutic indications were developed taking into account the present analysis and a literature review (2,338 in situ ductal carcinomas, palpable or not, treated with conservative surgery, with or without adjuvant radio-therapy).

[Conservative treatment of sub-clinical noninfiltrating cancers of the breast (102 EOA in situ, TONO)]. / Le traitement conservateur des cancers du sein infra-cliniques canalaires non infiltrants (102 EOA in situ, TONO).

102 patients with sub-clinical intra ductal non invasive breast cancer (T0N0) treated by limited surgery and curative radiation therapy. Follow-up ranged from 2 to 10 years with a median follow-up of 59 months. The long term survival rate of this therapeutic approach, consisting of simple excision without any adjuvant treatment and radical mastectomy was close to 100%. The actuarial local recurrence rate was only 8.6% at 10 years (confidence interval: 4.6 to 12.6%), which strongly suggests that radiation therapy is active on multicentric foci. Salvage surgery could be performed in every case of local recurrence. The survival rate of in situ breast cancer (T0N0) treated by conservative radio-surgery is comparable to that of radical mastectomy, while cosmetic results and psychological impact appear to be better for the conservative technique (breast preservation rate = 91 to 96%).

Stable integration and expression of the Plasmodium falciparum circumsporozoite protein coding sequence in mycobacteria.

The DNA coding for the circumsporozoite protein of Plasmodium falciparum (CSP; aa 1-412) has been placed under the control of the mycobacterial promoter derived from the gene encoding the 64-kDa antigen of Mycobacterium bovis-BCG. This expression cassette was cloned into pJRD184, an Escherichia coli multicloning site vector, together with the kanamycin resistance gene from Tn903 and the attachment site and integrase gene from the temperate mycobacteriophage FRAT1. One of the resulting plasmids, pNIV2173, introduced by electroporation into both Mycobacterium smegmatis and M. bovis-BCG, integrated at a specific site in the genome of each recipient. Recombinants expressed immunoreactive polypeptides, ranging in size from 62 to 43 kDa, at a level of about 1% of total soluble proteins. Part of this material was present in the culture medium indicating that mycobacterial recombinants were able to secrete the CSP. The M. smegmatis and M. bovis-BCG recombinants, transformed with pNIV2173 and grown in absence of antibiotic, were followed for more than 400 and 50 generations respectively. Over this time span, neither DNA rearrangement nor loss of expression was observed. Inoculation of the recombinant BCG to mice did not induce humoral response to CSP nor proliferative response to CSP Th2R CD4+ T lymphocyte epitope.

Local recurrence after breast-conserving surgery and radiotherapy. Frequency, time course, and prognosis.

Mammary recurrences were studied in 1593 patients with Stage I and II breast cancer treated by macroscopically complete tumor excision followed by megavoltage radiotherapy, including a boost to the tumor bed (mean dose, 78 Gy). The actuarial freedom from mammary recurrence was 93% at 5, 86% at 10, 82% at 15, and 80% at 20 years. Seventy-nine percent of the recurrences were in the vicinity of the tumor bed, but with increasing time interval, an increasing percentage of recurrences was located elsewhere in the breast. A majority of recurrences after 10 years could be considered new tumors. Only ten of 181 patients with recurrence had prior or concomitant distant metastases, and 159 of 171 isolated mammary recurrences (93%) were operable. Uncorrected overall survival after operable recurrence was 69% at 5 and 57% at 10 years. Prognosis after late recurrence (after 5 years) was favorable (84% 5-year survival). Operable early recurrences retained a favorable prognosis if smaller than 2 cm and confined to the breast (74% 5-year survival). Disease-free interval and histologic grade also appeared to be important prognostic factors after early recurrence. Survival after recurrence did not depend upon the type of salvage operation. Locoregional control was 88% at 5 years after salvage mastectomy and 64% after breast-conserving salvage procedures. The role of adjuvant systemic therapy at time of local recurrence requires additional study. This experience illustrates the important differences between mammary failure and chest wall recurrence after mastectomy, in particular the protracted time course and more favorable prognosis associated with the former.

Radiation therapy after breast-conserving surgery for Stage I and II mammary carcinoma. Results of the Marseille experience 1961 to 1976.

This report describes the results of a program of limited surgery, usually tumor excision, followed by curative radiation therapy in a series of 794 evaluable Stage I and II breast cancer patients treated prior to December, 1976. Clinical cure rates at 5, 10 and 15 years were 85%, 74% and 58% respectively. At 10 years, 86% of the apparently cured patients had the affected breast preserved, 79% of them with a good cosmetic result. In 10-year local/regional recurrence rate was 14%, but 84% of local failures were operable. Salvage surgery provided ultimate local control for 94% of the operable local failures, 61.5% of whom lived for at least 5 years after their secondary operations. It is concluded that a combination of primary tumor excision, limited axillary dissection and curative radiation therapy provides end results which are equivalent to those of primary radical mastectomy and affords the considerable advantage of successful breast preservation in a large majority of cases.

Radiation therapy with or without primary limited surgery for operable breast cancer: a 20-year experience at the Marseilles Cancer Institute.

Since 1960 more than 3000 consecutive patients with operable infiltrating breast carcinoma were treated by radiation therapy with or without primary limited surgery, which usually consisted of local excision. For tumors smaller than or equal to 5 cm the ten-year crude survival rate is 77% for patients without palpable axillary nodes (T1-2N0) and 63% for patients having axillary adenopathy (T1-2N0). For operable tumors exceeding 5 cm of diameter (T3N0-1) the ten-year crude survival is 34%. Thirty-five percent of the patients alive free of disease at ten years required a secondary operation for presumed local or regional tumor persistence or recurrence, although no residual disease was found in 24% of the operative specimens. Local-regional recurrence had no adverse effect on ten-year survival. This conservative approach offers most women with operable breast cancer an excellent chance at breast preservation with the same chance for ten-year survival as with radical mastectomy.

[Curative radiotherapy with hope of saving the breast in operable breast cancers 403 cases with 5-year survival]. / Radiothérapie curative à espérance conservatrice des cancers du sein opérables. 403 cas de 5 ans

Between 1960 and 1975, 1 078 operable mammary carcinomas were treated by caesium therapy with the objective of conserving the breast. The authors analyse the indications for and results of this treatment in the 403 cases which have had more than 5 years follow up (241 cases were irradiated as primary treatment, 162 after having a simple tumorectomy). For the whole group 92 mastectomies were ultimately carried out: in 30 of them no tumour was found in the operative specimen. The tumorectomy cases, restricted to stage 1 of the UICC classification (pre 1962) -- PRV 0 IGR yielded the best results: 86 per cent 5 yeat cures with 9 out of 10 women retaining both breasts. The primary irradiation cases, all types considered, gave results comparable with those for primary radical surgery: 58 per cent 5 year cures-but 2 out of 3 women retained both breasts. By itself caesium therapy is capable of eradicating tumour in breast and axilla in half of the cases. It really amounts to a "double chance strategy"--an attempt at cure if possible with avoidance of mastectomy, this being in reserve in the event of failure.