[Influence of hormonal factors on triple-negative breast cancer prognosis]

OBJECTIVES

Triples negative breast cancer defined by the absence of expression of the hormone receptors and HER2 protein, are considered as aggressive tumours with bad outcome in comparison to the hormone sensitive tumours. The aim of the study was to evaluate the link between hormone factors and prognostic factors of triple-negative tumours.

METHODS

All patients managed for a triple-negative breast cancer between January, 2009 and December, 2013 were included. For every patient, collected data were the clinical, histological, adjuvant or neoadjuvant treatments, as well as survival data.

RESULTS AND CONCLUSION

During the study period, 1682 patients were operated for a breast cancer, among which 1444 presented at least an invasive tumour. One hundred and fifty-five women (10.7%) had a negative triple tumour. The average age of diagnosis was 56.4years, is significantly younger than for patients with other types of tumours, P=0.0001. For women with a triple-negative tumour, the parity was the only hormonal factor identified as an independent factor for axillary lymph node involvement (OR=1.53; 95% CI [1.10-2.25] P=0.02) and previous hormone replacement therapy as an independent factor of locoregional recurrence (OR=0.13 [0.005-0.64] P=0.001). We did not find any hormonal factor predictive of distant metastasis. We did not find any difference in overall survival according to the parity (P=0.72), the Body mass index (P=0.62) or the use of HRT (P=0.49).

CONCLUSION

Hormone factors seem to have a prognostic implication for triple-negative despite the absence of hormone receptors expression.

[Prognosis impact of breast cancer adjuvant radiotherapy delay]

OBJECTIVES

To evaluate delay to access to adjuvant radiotherapy for women with breast cancer and to study impact on prognosis.

METHODS

A restrospective descriptive study in the teaching hospital of Tours between 1st January 2007 and 31th December 2013. All women managed for an invasive breast cancer during this period were included with exclusion of women with indication of chemotherapy (neoadjuvant/adjuvant). Delay between surgery and radiotherapy were recorded. Overall survival and recurrence free survival were used to evaluate the impact of delays on prognosis.

RESULTS

Of the 1855 women with an invasive breast cancer, 904 (48.7%) had an adjuvant radiotherapy without chemotherapy. In the whole population, a delay surgery-radiotherapy>90 days was found as an independent factor negatively impacting recurrence free survival (HR=2.12 [1.03-4.36] p=0.04). In the group of patient with a breast conservative surgery, a delay surgery-radiotherapy>65 days was found as an independent factor negatively impacting recurrence free survival with HR=2.29 [1.16-4.54], p=0.02. A delay surgery-radiotherapy>70 days was found as an independent factor negatively impacting Overall survival and HR=3.41 [1.005-11.62], p=0.04.

CONCLUSION

Delay to access to adjuvant radiotherapy is an independent factor impacting patient's survival, especially in the case of breast conservative therapy.

[Predictive factors of conservative breast surgery after neoadjuvant chemotherapy for breast cancer]

OBJECTIVES

The aim of our study was to evaluate the existence of predictive factors of conservative breast surgery after neoadjuvant chemotherapy (NAC) for breast cancer.

METHODS

We included all women with invasive breast cancer who received NAC and underwent breast surgery between January 2007 and December 2013 in our institution. Univariable and multivariable analyses were performed to determine the association between clinical and histological factors and conservative breast surgery.

RESULTS

During the study period, 229 women were included of whom 73 had breast conservative surgery (32%). At univariable analysis, significant predictive factors were age (OR 0.97 [CI 95% 0.95-0.99], P=0.02), radiological size (OR 0.97 [CI 95% 0.96-0.99], P<0.001), multifocality (OR 0.53 [CI 95% 0.27-1.05], P=0.06), breast inflammation (OR 0.15 [CI 95% 0.07-0.32], P<0.001) and the type of hormone receptors (P=0.12). In multivariable analysis, all these factors but age were significant factors and thus considered as independent predictive factors.

CONCLUSION

This work permitted to identify independent predictive factors of breast conservative surgery after NAC for breast cancer that will be included in a risk scoring system that we aim to evaluate prospectively.

DNA and cell cycle analysis as prognostic indicators in breast tumors revisited

Both DNA ploidy and S-phase ploidy are promising prognostic factors for node-negative breast cancer patients. Based largely on the analysis of one large study, much of the reported problems with these factors have been caused by some unappreciated complexities in categorizing DNA ploidy into low- and high-risk groups and the lack of some necessary adjustments to eliminate unwanted correlations between DNA S-phase and ploidy. When both DNA ploidy and S-phase are compensated properly, they become independent prognostic markers, forming a powerful prognostic model.

Optimizing flow cytometric DNA ploidy and S-phase fraction as independent prognostic markers for node-negative breast cancer specimens

Developing a reliable and quantitative assessment of the potential virulence of a malignancy has been a long-standing goal in clinical cytometry. DNA histogram analysis provides valuable information on the cycling activity of a tumor population through S-phase estimates; it also identifies nondiploid populations, a possible indicator of genetic instability and subsequent predisposition to metastasis. Because of conflicting studies in the literature, the clinical relevance of both of these potential prognostic markers has been questioned for the management of breast cancer patients. The purposes of this study are to present a set of 10 adjustments derived from a single large study that optimizes the prognostic strength of both DNA ploidy and S-phase and to test the validity of this approach on two other large multicenter studies. Ten adjustments to both DNA ploidy and S-phase were developed from a single node-negative breast cancer database from Baylor College (n = 961 cases). Seven of the adjustments were used to reclassify histograms into low-risk and high-risk ploidy patterns based on aneuploid fraction and DNA index optimum thresholds resulting in prognostic P values changing from little (P < 0.02) or no significance to P < 0.000005. Other databases from Sweden (n = 210 cases) and France (n = 220 cases) demonstrated similar improvement of DNA ploidy prognostic significance, P < 0.02 to P < 0.0009 and P < 0.12 to P < 0.002, respectively. Three other adjustments were applied to diploid and aneuploid S-phases. These adjustments eliminated a spurious correlation between DNA ploidy and S-phase and enabled them to combine independently into a powerful prognostic model capable of stratifying patients into low, intermediate, and high-risk groups (P < 0.000005). When the Baylor prognostic model was applied to the Sweden and French databases, similar significant patient stratifications were observed (P < 0.0003 and P < 0.00001, respectively). The successful transference of the Baylor prognostic model to other studies suggests that the proposed adjustments may play an important role in standardizing this test and provide valuable prognostic information to those involved in the management of breast cancer patients.

S-phase fraction and DNA ploidy in 633 T1T2 breast cancers: a standardized flow cytometric study

The lack of a standardized methodology for quantifying DNA ploidy and S-phase fraction (SPF) by flow cytometry is hindering routine use of these markers in breast cancer management. In a retrospective clinical multicenter study, we validated a standardized flow cytometry protocol. We tested 633 frozen T(1)T(2), N(0)N(1), M(0) breast tumors obtained in four institutions. Cell preparation was standardized, and precise rules for data interpretation were followed. Three SPF classes were defined on the basis of tertiles after adjustment for ploidy. DNA aneuploidy was observed in 61.0% of cases. No significant difference was observed among centers. Aneuploidy and high SPF were associated with large tumor size, node involvement, high histological grade, and hormone receptor negativity. In the overall population (median follow-up, 69 months), patients with medium and high SPF values had shorter disease-free survival (DFS) than those with low SPF values (P < 0.0001). Ploidy had no significant influence. By Cox analysis, SPF, pN, and estrogen receptor status were independent predictors of DFS (P = 0.0002, P = 0.001, and P = 0.05). In node-negative patients, SPF was the only predictor of DFS (P = 0.01), whereas in node-positive patients, the risk of relapse increased with both high SPF (P = 0.003) and estrogen receptor negativity (P = 0.004). Low SPF values distinguished grade II tumors with a particularly good outcome. Our results strongly support the use of SPF in multicenter studies and clinical trials and suggest that node-negative patients with slowly proliferating tumors do not require systemic adjuvant therapy.

Effect of an alpha-linolenic acid-rich diet on rat mammary tumor growth depends on the dietary oxidative status

To investigate whether the oxidative status of an 18:3(n-3) polyunsaturated fatty acid (PUFA)-enriched diet could modulate the growth of chemically induced rat mammary tumors, three independent experiments were performed. Experiments I and II examined the variation of tumor growth by addition of antioxidant (vitamin E) or a prooxidant system (sodium ascorbate/2-methyl-1,4-naphthoquinone) to a 15% linseed oil diet rich in 18:3(n-3). Experiment III addressed the role of PUFA in the tumor growth modulation by vitamin E. For this purpose, we compared the effect of vitamin E in 15% fat diets containing a high level of 18:3(n-3) (linseed oil, high-PUFA diet) or devoid of 18:3(n-3) (hydrogenated palm/sunflower oil, low-PUFA diet). In Experiments I-III, tumor growth increased in the presence of vitamin E compared with control (without vitamin E). Furthermore, it decreased when prooxidant was added. In contrast, no difference was observed when the diet was low in PUFA, suggesting that sensitivity of PUFA to peroxidation may interfere with tumor growth. This observation was supported by growth kinetic parameter analysis, which indicated that tumor growth resulted from variations in cell loss but not from changes in cell proliferation. These data show that, in vivo, PUFA effects on tumor growth are highly dependent on diet oxidative status.

[Standardization and quality control in the evaluation of proliferation parameters in T1T2, N0N1, M0 breast cancer: multicentric retrospective study II. DNA-ploidy and S-phase fraction]

As part of a clinical research project, proliferative parameters were studied in primary breast cancer: standardization and technical validation of thymidine kinase (TK), thymidylate synthase (TS) and protein tyrosine kinase (PTK) are described. A total of 633 frozen tumor specimens, available in four institutions, was analyzed in three flow cytometry laboratories for DNA content and percentage of S-phase cells (%S) measurement. 1) The standardization step consisted in developing a common protocol for sample preparation; then, common cell suspensions were analyzed in order to perform an inter-laboratory control. Objective guidelines were elaborated to interpret DNA histograms in breast carcinoma. 2) DNA-aneuploidy was observed in 61% of cases of the retrospective series. Compared with DNA-aneuploid tumors, mean %S was significantly lower in case of DNA-diploidy (respectively: 6.4% and 2.2%, p < 0.001). When compared between the four institutions, %S distributions did not differ significantly. 3) %S is strongly correlated with TK, TS and PTK and high percentages were also observed in high grade tumors or tumor without hormone receptors. These results show that a standardization in using flow cytometers and DNA software allows multicenter studies.

Suppression of the promoter effect of polyunsaturated fatty acids by the absence of dietary vitamin E in experimental mammary carcinoma

Because lipoperoxides seem able to modulate tumor growth, we have examined the concomitant effects of dietary antioxidant (vitamin E) and of a high amount of polyunsaturated fatty acids (PUFA) in a model of chemically-induced mammary carcinogenesis. Two groups of rats received a high fat diet with or without added vitamin E and mammary tumors were initiated in both groups by an injection of carcinogen. Tumor growth was followed in both groups. We found that tumor incidence and growth were decreased in rats with no added vitamin E in diet, suggesting a protective role of oxidized PUFA at later stages of carcinogenesis.

Detection and typing of human papillomaviruses by in situ hybridization with biotinylated oligonucleotide mixtures

The value of biotinylated oligonucleotide probes for screening and typing by in situ hybridization of the most frequent genital human papillomavirus infections (HPVs 6, 11, 16, 18, 31, and 33) was assessed. Optimal hybridization conditions were defined on a panel of paraffin-embedded tissue sections previously characterized with HPV full genome probes. Mixtures of oligonucleotides rather than single oligonucleotides were used to improve sensitivity and specificity. All HPV-positive specimens were detected by the screening mixture with a sensitivity and specificity similar to that of full genome probes. Typing mixtures were highly specific for each HPV type. This study confirms the potential of oligonucleotide probes for detecting and typing HPV infections.

Prolonged stable hypothermia: effect on blood gases and pH in rats and ground squirrels

Richardson's ground squirrels [body temperature (Tb) 7 degrees C] survive prolonged stable hypothermia for three times as long as do rats (Tb 19 degrees C) (72 vs. 24 h). We have examined the changes in blood gases and acid-base state to assess whether these contribute to this difference in survival time. None of the variables (measured at ambient temperature of 25 degrees C) differed significantly between rats and ground squirrels before hypothermic induction. During cooling, neither hematocrit nor plasma lactate changed significantly, but arterial and venous PO2 and PCO2 increased and arterial and venous pH decreased in both groups. During prolonged hypothermia, hematocrit increased significantly in rats (58.8 +/- 1.7% at 24 h) but not in ground squirrels (39.1 +/- 1.0% at 72 h). Both species maintained stable arterial blood gases but showed decreased venous PO2; arterial and venous pH decreased significantly with time in both species in conjunction with increased plasma lactate. These patterns of decreased venous PO2 and increased plasma lactate suggest that reduced tissue oxygenation occurs during hypothermia. This happens earlier in rats at a Tb of 19 degrees C than in ground squirrels at a Tb of 7 degrees C, possibly as a result of increased hematocrit in hypothermic rats. Remedial measures directed at improving tissue O2 delivery may therefore prolong the hypothermic survival of rats.

Acute measles encephalitis of the delayed type: neuroradiological and immunological findings

A case of delayed acute measles encephalitis in an immunosuppressed child is reported. Detailed immunological studies have shown defective humoral immunity (defective IgA, IgG2 and IgG3) and decreased natural killer activity. Neuroradiological examination by magnetic resonance imaging revealed several high signal lesions on T2-weighted images in the gray matter without clinical or pathological correlation. The implications of these findings are discussed.

Seasonal changes in methionine-enkephalin immunoreactivity in the brain of a hibernator, Spermophilus columbianus

To identify the actual location of central endogenous opioid systems which may be involved in regulating the hibernation cycle, differences in the pattern of central methionine-enkephalin (Met-EK) immunoreactivity were compared between hibernating (body temperature, Tb = 7 degrees C) and non-hibernating (Tb = 37 degrees C) Columbian ground squirrels using the peroxidase-antiperoxidase technique. In non-hibernating animals, Met-EK-immunoreactive perikarya were observed in telencephalic (putamen, caudate nucleus, medial septum-diagonal band complex, amygdala) and diencephalic (periventricular hypothalamic nucleus, lateral hypothalamic area) regions, whereas immunoreactive fibers were found in the lateral septum, stria terminalis nucleus, various hypothalamic areas, arcuate nucleus, median eminence, thalamic intralaminar, periventricular nucleus and lateral habenular nucleus. Compared to the non-hibernating animal, a marked increase in the number of Met-EK-immunoreactive fibers was found in the lateral septal nucleus, the periventricular nucleus, the intralaminar thalamus and the paraventricular hypothalamus of hibernating ground squirrels. Since these changes in immunoreactivity were not observed in the artificially induced hypothermic ground squirrels (Tb = 7 degrees C), it is unlikely that the dissimilarity in immunoreactivity between animals from different hibernating phases is due to differences in their Tb. In combination with our previous studies, these results tend to suggest that hibernation may be brought about by an increase in endogenous opioid activity, especially in the lateral septal region.

Plasma glucagon, glucose, and free fatty acid concentrations and secretion during prolonged hypothermia in rats

Impairment of metabolic substrate mobilization and utilization may be a factor limiting survival in hypothermia. Using a newly developed technique for maintaining stable low body temperature (Tb), substrate profiles and their regulation by glucagon were examined in hypothermic rats (Tb 19 +/- 0.3 degrees C) over 20 h. During cooling, plasma glucagon, glucose, and free fatty acid (FFA) concentrations increased significantly (536 +/- 55 pg/ml, 304 +/- 26 mg/100 ml, and 844 +/- 81 mueq/l, respectively). Plasma glucagon and glucose concentrations continued to increase up to 8 h (peaks 810 +/- 103 pg/ml and 451 +/- 33 mg/100 ml, respectively) and remained high throughout the rest of the hypothermic period. FFA concentrations decreased steadily during the hypothermic period. Exogenous glucagon (20 micrograms/kg) induced significant increases in plasma glucose (+129 +/- 31 mg/100 ml) and FFA concentrations (+351 mueq/l) at 2 h but had no effect at 15 h of hypothermia. In vitro evaluation of pancreatic alpha-cell function indicated that glucagon secretion is independent of temperature between 37 and 19 degrees C. Our data indicate that hypothermia is characterized by a disturbed substrate metabolism, which is likely due to an imbalance in pancreatic alpha- and beta-cell function and a time-dependent decrease in tissue sensitivity to glucagon. These deleterious changes may limit survival in hypothermia.

Mechanisms underlying the supra-maximal thermogenesis elicited by aminophylline in rats

Previous studies showed that acute treatment with aminophylline (AMPY) significantly elevated maximum thermogenesis and improved cold tolerance in rats and man in severe cold. However, the exact mechanism by which AMPY enhances thermogenesis was unknown. Rats receiving enprofylline (ENPRO) (1.5 and 15 mg/kg, i.p.), a selective phosphodiesterase inhibitor, failed to show enhanced thermogenesis. In contrast, treatment with a selective adenosine receptor antagonist, 8-phenyltheophylline(8-PT; 2.5 to 10 mg/kg, i.p.), significantly increased (p less than 0.05) thermogenesis and cold tolerance. However, the maximal thermogenic effect by optimal dose of 8-PT (5 mg/kg) was significantly lower than that with optimal dose of AMPY (18.7 mg/kg, i.p.); the deficit could be eradicated by combining optimal 8-PT dose with a low dose of AMPY (1.25 mg/kg), but not with ENPRO. These results indicate that the thermogenic effect of AMPY is not by inhibition of phosphodiesterase but at least partially by antagonism of adenosine receptors. It is also apparent that older mechanisms in addition to adenosine antagonism are also involved in AMPY's thermogenic action.

Insulin secretion and substrate homeostasis in prolonged hypothermia in rats

In hypothermia, impairment of metabolic substrate mobilization and utilization may be a factor limiting survival. By use of a newly developed technique, substrate profiles and their regulation by insulin were examined in hypothermic rats (body temperature 19 degrees C) over 24 h. Plasma glucose concentrations increased to approximately 300 mg/dl during cooling and remained high throughout the period of hypothermia. Free fatty acid (FFA) concentration was not altered during cooling or during the first 10 h of hypothermia (approximately 700 mu eq/l) but progressively decreased thereafter, reaching 420 mu eq/l by 20 h. Plasma insulin decreased dramatically during cooling and remained very low (9 +/- 2 microU/ml) during the whole period of hypothermia, reflecting the suppression of insulin secretion by isolated islets at low temperatures. To test he hypothesis that suppression of endogenous insulin secretion may hamper glucose utilization and thus limit survival in hypothermia, exogenous insulin was administered. At doses of 0.1, 0.5, and 1 U/kg intravenously, insulin slowly decreased plasma glucose and FFA. However, at 0.1 and 1 U/kg intraperitoneally, insulin resulted in a dose-dependent decrease in survival time in the hypothermic rat. It is possible that the antilipolytic effect of insulin may have outweighed any beneficial effect of improving glucose utilization in hypothermia.

The "hibernation induction trigger": specificity and validity of bioassay using the 13-lined ground squirrel

Even though the existence of the blood-borne "hibernation induction trigger" has been reported in the 13-lined ground squirrel, transfusion of plasma from hibernating rodents with other hibernating species as the recipients failed to induce the occurrence of summer hibernation. In order to verify whether the response to the "trigger" substance is species specific, the present study was carried out to compare the effect of plasma from hibernating Richardson's ground squirrels on the incidence of summer hibernation in both juvenile Richardson's and adult 13-lined ground squirrels. In two series of experiments, 13-lined ground squirrels entered hibernation quite readily independent of the treatment. The rate of occurrence of hibernation ranged from 78% after sham injection to 86% after warm saline, fresh summer active plasma, and fresh hibernating plasma, respectively. There were no differences in the number of hibernation bouts and the number of days in hibernation after each treatment. In contrast, none of the juvenile Richardson's ground squirrels entered hibernation after any of the treatments up to the end of the 8-week observation period. These results not only argue against the existence of blood-borne "trigger" substance, at least in the Richardson's ground squirrel, but also caution against the use of the 13-lined ground squirrel as a standard test animal for the bioassay of the "trigger" substance.

Seasonal difference in thermoregulatory responses to opiates in a mammalian hibernator

Accumulated evidence suggests that increased endogenous opioid activities may facilitate the onset of hibernation. The present study investigated the change in thermoregulatory responses following ICV infusion of morphine or [D-Ala2]-Met enkephalinamide (EK) in unanesthetized, unrestrained Columbian ground squirrels (Spermophilus columbianus) during its annual hibernation cycle. In the nonhibernating phase, low doses of either morphine (less than 160 micrograms) or EK (less than 400 micrograms) elicited a dose-related hyperthermia and an increase in heat production, whereas a higher dose of opiates caused hypothermia and a decrease in metabolic rate. Naloxone (5 mg/kg, SC) pretreatment reduced or reversed both the hyper- and hypothermic responses to opiates. Lower ambient temperature (5 degrees C) enhanced the hypothermic response and attenuated the hyperthermic response. In the hibernating phase, euthermic ground squirrels exhibited a reduced responsiveness to exogenous opiates: the hyperthermic response to low dose of morphine (10 micrograms) was significantly reduced and hyperthermia, rather than hypothermia was observed at the highest dose of morphine (160 micrograms). The reduced responsiveness to opiates observed during the hibernating phase seems to suggest a reduction in opiate receptor efficacy which is in agreement with the contention that an increase in endogenous opioid activities may be incumbent with the commencement of hibernation.

Effects of fasting and aminophylline on norepinephrine-stimulated non-shivering thermogenesis

In an attempt to further elucidate the mechanisms of fasting-depressed maximum thermogenesis and cold tolerance, norepinephrine (NE)-stimulated non-shivering thermogenesis (NST) in cold-acclimated rats was used as a functional index of possible alterations in adrenergic efficacy after fasting. Fasting decreased the magnitude of maximum NE-Stimulated NST by 18.2% [6.87 +/- 0.47 Kcal (Kg X 75 X min)-1 well-fed vs. 5.81 +/- 0.39 Kcal (Kg X 75 X min)-1 fasted], but the apparent adrenergic binding affinity was not affected [Ke = 0.43 micrograms NE min-1 well-fed vs. 0.55 micrograms NE min-1 fasted]. Pretreatment with aminophylline [15 mg Kg-1, i.p.], a phosphodiesterase inhibitor, restored the fasting-depressed NE-stimulated NST to the fed level. The results suggest that the depression of maximum thermogenesis after fasting is not due to changes in adrenergic binding characteristics but to alteration in cAMP production/degradation, resulting in decreased substrate mobilization for thermogenesis.