MICROSCOPE Mission: Final Results of the Test of the Equivalence Principle

The MICROSCOPE mission was designed to test the weak equivalence principle (WEP), stating the equality between the inertial and the gravitational masses, with a precision of 10^{-15} in terms of the Eötvös ratio η. Its experimental test consisted of comparing the accelerations undergone by two collocated test masses of different compositions as they orbited the Earth, by measuring the electrostatic forces required to keep them in equilibrium. This was done with ultrasensitive differential electrostatic accelerometers onboard a drag-free satellite. The mission lasted two and a half years, cumulating five months worth of science free-fall data, two-thirds with a pair of test masses of different compositions-titanium and platinum alloys-and the last third with a reference pair of test masses of the same composition-platinum. We summarize the data analysis, with an emphasis on the characterization of the systematic uncertainties due to thermal instabilities and on the correction of short-lived events which could mimic a WEP violation signal. We found no violation of the WEP, with the Eötvös parameter of the titanium and platinum pair constrained to η(Ti,Pt)=[-1.5±2.3(stat)±1.5(syst)]×10^{-15} at 1σ in statistical errors.

The TP53 Arg72Pro and MDM2 309G>T polymorphisms are not associated with breast cancer risk in BRCA1 and BRCA2 mutation carriers

Background:

The TP53 pathway, in which TP53 and its negative regulator MDM2 are the central elements, has an important role in carcinogenesis, particularly in BRCA1- and BRCA2-mediated carcinogenesis. A single nucleotide polymorphism (SNP) in the promoter region of MDM2 (309T>G, rs2279744) and a coding SNP of TP53 (Arg72Pro, rs1042522) have been shown to be of functional significance.

Methods:

To investigate whether these SNPs modify breast cancer risk for BRCA1 and BRCA2 mutation carriers, we pooled genotype data on the TP53 Arg72Pro SNP in 7011 mutation carriers and on the MDM2 309T>G SNP in 2222 mutation carriers from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). Data were analysed using a Cox proportional hazards model within a retrospective likelihood framework.

Results:

No association was found between these SNPs and breast cancer risk for BRCA1 (TP53: per-allele hazard ratio (HR)=1.01, 95% confidence interval (CI): 0.93–1.10, P_trend=0.77; MDM2: HR=0.96, 95%CI: 0.84–1.09, P_trend=0.54) or for BRCA2 mutation carriers (TP53: HR=0.99, 95%CI: 0.87–1.12, P_trend=0.83; MDM2: HR=0.98, 95%CI: 0.80–1.21, P_trend=0.88). We also evaluated the potential combined effects of both SNPs on breast cancer risk, however, none of their combined genotypes showed any evidence of association.

Conclusion:

There was no evidence that TP53 Arg72Pro or MDM2 309T>G, either singly or in combination, influence breast cancer risk in BRCA1 or BRCA2 mutation carriers.

Interaction of human cyclophilin hCyp-18 with short peptides suggests the existence of two functionally independent subsites

The binding of peptides, derived from the model substrate Suc-Ala-Ala-Pro-Phe-pNA, to the human cyclophilin hCyp-18 was investigated. HCyp-18 is able to bind 2-4-mer peptides as well as shorter para-nitroaniline (pNA) derivatives and pNA surrogates. Although Suc-Ala-Phe-pNA binds hCyp-18, only proline-containing peptides are able to block efficiently the peptidyl-prolyl cis/trans isomerase activity. Competition experiments strongly suggest the existence of two independent subsites: a S1' 'proline' subsite and a S2'-S3' 'pNA' subsite. The interaction at S2'-S3' requires either a Phe-pNA C-terminus or a Phe-pNA surrogate bearing an H-bond acceptor able to bind Trp121 and Arg148 simultaneously.

[Do indications remain for total mastectomy for cancer?]

Does radical mastectomy for cancer remain needed? Breast conserving treatment may be achieved by surgery, primary chemotherapy followed by radiotherapy and surgery. This article attempts at defining (according to clinical and pathological parameters of the tumor and patient's characteristics), when conservative treatment is not allowed and radical mastectomy must be performed. Mastectomy must be performed first when there are multiple tumors or a tumor too large with respect to the breast volume or diffuse microcalcifications on mammograms. Sometimes the stage of pregnancy, a personal history of collagen vascular disease or prior radiotherapy or the willing of the patient lead to perform radical mastectomy. Secondary mastectomy is necessary in case of failure of conservative treatment or recurrence after breast conserving treatment.

Measurement of cutaneous erythema by means of photodensitometry: application to cutaneous photosensitivity

We have developed a photodensitometry method to evaluate the intensity of cutaneous erythema objectively. The method measures the optical density of photographic slides of cutaneous erythema. It combines techniques used commonly but separately by investigators: diffuse transmittance spectroscopy (which is a variant of diffuse reflectance spectroscopy) and photography. We have used this method to study photosensitivity in 22 volunteers who received increasing doses of ultraviolet radiation to the back. Our work confirms the usefulness of an important parameter in photobiology: the regression slope of the curve representing the erythema index, a function of the logarithm of the dose applied.

Mutation spectrum and genotype-phenotype analyses in Cowden disease and Bannayan-Zonana syndrome, two hamartoma syndromes with germline PTEN mutation

The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403 amino acid dual specificity phosphatase (protein tyrosine phosphatase; PTPase), was shown recently to play a broad role in human malignancy. Somatic PTEN deletions and mutations were observed in sporadic breast, brain, prostate and kidney cancer cell lines and in several primary tumours such as endometrial carcinomas, malignant melanoma and thyroid tumours. In addition, PTEN was identified as the susceptibility gene for two hamartoma syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD families and seven BZS families was screened for germline PTEN mutations. PTEN mutations were identified in 30 of 37 (81%) CD families, including missense and nonsense point mutations, deletions, insertions, a deletion/insertion and splice site mutations. These mutations were scattered over the entire length of PTEN , with the exception of the first, fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD mutations identified in this exon. Seven of 30 (23%) were within the core motif, the majority (five of seven) of which were missense mutations, possibly pointing to the functional significance of this region. Germline PTEN mutations were identified in four of seven (57%) BZS families studied. Interestingly, none of these mutations was observed in the PTPase core motif. It is also worthy of note that a single nonsense point mutation, R233X, was observed in the germline DNA from two unrelated CD families and one BZS family. Genotype-phenotype studies were not performed on this small group of BZS families. However, genotype-phenotype analysis inthe group of CD families revealed two possible associations worthy of follow-up in independent analyses. The first was an association noted in the group of CD families with breast disease. A correlation was observed between the presence/absence of a PTEN mutation and the type of breast involvement (unaffected versus benign versus malignant). Specifically and more directly, an association was also observed between the presence of a PTEN mutation and malignant breast disease. Secondly, there appeared to be an interdependent association between mutations upstream and within the PTPase core motif, the core motif containing the majority of missense mutations, and the involvement of all major organ systems (central nervous system, thyroid, breast, skin and gastrointestinal tract). However, these observations would need to be confirmed by studying a larger number of CD families.

[Intraoperative radiotherapy of ORL cancers. Review of the literature]

An optimal treatment of head and neck carcinoma is to be targeted at obtaining a good local control of the disease. Intraoperative radiotherapy is one of the means of increasing the irradiation dose in the tumoral volume. It appears particularly suitable for initial treatment of locally advanced head and neck lesions and treatment of recurrence of non irradiated tumors.

[Partial regression of Barret esophagus with high grade dysplasia and adenocarcinoma after photocoagulation and endocurietherapy under antisecretory treatment]

Barrett's oesophagus is a premalignant condition. The possibility of eradicating at least partially the metaplastic epithelium has been reported recently. In this case report, a patient with Barrett's oesophagus complicated by high grade dysplasia and focal adenocarcinoma was treated by Nd:Yag laser then high dose rate intraluminal irradiation while on omeprazole 40 mg/day. A partial eradication of Barrett's oesophagus and a transient tumoural regression were obtained. Histologically, residual specialized-type glandular tissue was observed beneath regenerative squamous epithelium. Four months after intraluminal irradiation, a local tumoural recurrence was detected while the area of restored squamous epithelium was unchanged on omeprazole 40 mg/day. This indicates that physical destruction of Barrett's oesophagus associated with potent antisecretory treatment can induce a regression of the metaplastic epithelium, even in presence of high grade dysplasia. The persistence of specialized-type glands beneath the squamous epithelium raises important issues about its potential malignant degeneration.

Chronology of combined chemotherapy (5FU) and radiotherapy. II. In vivo study

In a previous study, we reported that repeated combined chemotherapy and radiotherapy, and a single combined treatment had different consequences. In this study the effect of the chronology of the repeated combined treatments was tested, i.e. it was determined whether the treatment is more efficient when the first treatment is Fluorouracil or irradiation, or when they are given simultaneously. It was first demonstrated that, under our conditions, neither radiotherapy nor chemotherapy were chronodependent. The combined treatments were more efficient that the single treatment although their chronology had no significant consequences. Nevertheless, the simultaneous treatment appeared slightly better than the administration of Fluorouracil 6 h before or 6 h after irradiation. These results confirm our in vitro experiments.

Chronology of combined chemotherapy (5FU) and radiotherapy. I. In vitro study

Since radiotherapy or chemotherapy alone may be ineffective, they are more and more often combined. In this in vitro studies the effects of the chronology of the treatments and of the time interval between them are evaluated. In murine leukaemia L1210 cells and in murine mammary adenocarcinoma Ca755 cells the highest efficacy, i.e. the lowest survival fraction, was observed when radiotherapy was administered 6 h before Fluorouracil (FU). To mimic treatment in man, a daily combined treatment was also tested. Under these circumstances, the chronology of the treatments and the time interval between them had different consequences, the highest efficacy being noticed when both treatments were given at the same time.

Superimposition of computed tomography and single photon emission tomography immunoscintigraphic images in the pelvis: validation in patients with colorectal or ovarian carcinoma recurrence

A method of superimposing computed tomography (CT) and immunoscintigraphic (IS) single photon emission tomography (SPET) slices is presented and has been applied to 10 patients with suspected cancer recurrence. IS was performed with carcinoembryonic antigen (CEA)-specific indium-111 monoclonal antibodies (MoAbs) in 5 patients with colorectal cancer, and with OC125 111In-MoAbs in 5 patients with ovarian cancer. All patients had an abnormal CT image result in the pelvis, which was interpreted 5 times as recurrence, once as doubtful and four times as scar fibrosis. Recurrence was subsequently proven in all patients. Bone scintigraphy (BS) SPET was recorded at the same time as IS. No special technique was used during BS, IS or CT acquisition. CT images were fed into a computer using a CCD camera. Using the internal anatomical landmarks provided by the pelvic bone structures seen on CT and BS, an operator had to select corresponding fiducial points, which were used by the software to register the images. The final results were CT-BS and CT-IS superimposed images. CT-BS images were used for quality control. In all patients, the inspection of CT-BS and CT-IS showed that the registration process is accurate and assists in the co-interpretation of CT and IS images.

[Cancer of the esophagus after mediastinal radiotherapy for Hodgkin's disease. Apropos of a case]

Malignant solid tumors induced by radiotherapy for Hodgkin's disease are uncommon. We report one case of thoracic esophageal squamous carcinoma diagnosed 19 years after mediastinal irradiation. The criteria usually accepted for the diagnosis of radiation cancer were all present in this case. An oesophagectomy was performed and the patient made a good recovery from the operation.

Neoadjuvant chemotherapy and irradiation in multiple synchronous squamous cell carcinoma of the upper aero digestive tract

Twenty-four patients with multiple, synchronous carcinoma of the head and neck, lung or esophagus, were treated with induction chemotherapy followed by irradiation to involved areas. Chemotherapy regimen consisted of cisplatinum either alone, or in combination with 5-FU or etoposide. Subsequently, external radiotherapy, 60-65 Gy and 70-75 Gy to the mediastinum and the head and neck areas, respectively, was carried out. Following chemotherapy, three patients (12.5%) had a complete clinical remission in both cervical and mediastinal sites. That rate was significantly increased by radiotherapy (66%). Tolerance was fair or mild even though half of the patients needed a rest break during irradiation. Follow-up ranges from 24 to 38 months. The median survival is 12 months and the actuarial survival rates are 45% and 5% at 12 and 24 months, respectively. It is suggested that induction chemotherapy will not drastically improve the overall prognosis of multiple squamous cell carcinoma of the upper aero digestive tract and that external irradiation remains a major part of treatment which should not be reduced in treated volumes, or in total dose delivered.

Single brain metastasis of non-small cell lung carcinoma. Study of survival among 54 patients

We studied 54 patients treated for non-small cell lung carcinoma with single brain metastasis presenting between 1980 and 1985. Better survival was obtained in cases of patients presenting a fair neurological condition who were treated by surgery. Histological condition and date of onet of metastasis had no significant influence on survival. Combined treatment of both primary lung tumour and brain metastasis was a favourable prognosis element, and surgical resection of both locations led to the best results in terms of duration and quality of survival.

Squamous cell carcinoma of the upper aero-digestive tract in women

Between 1970 and 1985, 95 women presenting carcinomas of the oral cavity, pharynx or larynx, were treated at the Institut Jean-Godinot. Classification of these patients according to age shows a bimodal curve and the existence of two different populations. The main difference between groups appears to be the existence or not of tobacco intoxication. According to this criteria, the two groups of patients are statistically different in mean age (nonusers 16 years older than users, p less than 0.01) and in the site of the primary, with an excess of carcinomas of the oral cavity in the nonusers group (p less than 0.01). In contrast, no difference was found in the locoregional extension of the tumor (TNM), in the modalities and result of treatment or in the evolution and survival of patients.

Rapid hyperfractionated radiotherapy. Clinical results in 178 advanced squamous cell carcinomas of the head and neck

The authors present a series of 178 patients with Stage III or IV squamous cell carcinoma of the head and neck treated by rapid irradiation using multiple and small fractions per day. An initial group of 91 patients (G1) received a total dose of 72 Gy in 80 sessions and 10 days, according to the following split course schedule: J1 to J5, 36 Gy in 40 sessions, eight daily fractions of .9 Gy separated by 2 hours; J6 to J20, rest period; J21 to J25, same as in J1 except that the spinal cord was shielded. This protocol was altered for the following 87 patients (G2) by lessening the total dose to 60 to 66 Gy and the number of fractions to 60. The rest period was lengthened to 4 weeks. All patients but five completed the whole program and the minimal follow-up period was 24 months. At the end of irradiation, 121 patients achieved a total remission, but local recurrences occurred in 56%. Moreover, acute intolerance was considered as severe in 34% of G1 patients, and included extensive mucosal necrosis and bleeding. Although this rate was significantly reduced in G2 patients, late complications were observed in 20 of the 25 survivors, and included trismus, cervical sclerosis, and recurrent laryngeal edema. The crude survival rate is 13% at 2 years. Although this study was not randomized, this particular type of accelerated and hyperfractionated combination of irradiation did not really improve the clinical results in advanced carcinoma of the head and neck. Other schedules and probably other tumors, less extended, should be tested.

The use of a concomitant electron boost (field in the field technique) in large cervical node metastases over a shortened period

Seven patients with large cervical node metastases were treated at the Institut Jean-Godinot using a particular scheme of accelerated irradiation. Conventional Cobalt-60 radiotherapy was prophylactically delivered to extended volumes of the neck (50 Gy in 25 fractions over 5 weeks). Within the fields of cobalt irradiation, an electron beam field was added to increase the daily dose from 2 to 3 Gy (Fletcher's field in the field technique). The increment of dose was limited to nodal area. Since no interval separated the two irradiations, involved areas were considered to receive 70 Gy in 25 fractions over 5 weeks and non-clinically involved areas to receive 50 Gy in 25 fractions over 5 weeks. In all the cases, the malignant mass diameter exceeded 5 cm. Acute tolerance was good and no major late injury was observed during the 18 months minimum follow-up period. At the end of the treatment, a complete disappearance of the tumor was observed in six out of seven cases. At the present time, four patients are still alive without evidence of disease. Slight acceleration of irradiation by the use of a concomitant electron boost is easily feasible and may provide an improvement in local control and therapeutic ratio of large cervical malignant masses in the neck.

Hyperfractionated radiotherapy with or without misonidazole: results of a prospective randomized study in stage III-IV squamous cell carcinoma of the head and neck

From 1979 to 1980, 52 patients with Stage III-IV squamous cell carcinoma of the head and neck were included in a prospective randomized study on hyperfractionated radiotherapy with or without misonidazole. The radiotherapeutic schedule consisted of two weeks of treatment split by a rest-period of one month, 6 X 1.1 Gy fractions per day for 5 consecutive days (total dose: 2 X 33 Gy/30 f/5 d). Total dose of misonidazole was 12 g/m2 administered daily in 1.2 g/m2 fractions. The overall tolerance of misonidazole was good, with a neuropathy rate of 5.7%. Local control, recurrence and 3 year survival rates did not statistically differ between the two groups. The randomized trials published at the present time, including our own, suggest that misonidazole has no beneficial effect with classical, concentrated or multiple fractions per day radiotherapy.