FAIRLANE, a double-blind placebo-controlled randomized phase II trial of neoadjuvant ipatasertib plus paclitaxel for early triple-negative breast cancer

BACKGROUND

This hypothesis-generating trial evaluated neoadjuvant ipatasertib-paclitaxel for early triple-negative breast cancer (TNBC).

PATIENTS AND METHODS

In this randomized phase II trial, patients with early TNBC (T ≥ 1.5 cm, N0-2) were randomized 1 : 1 to receive weekly paclitaxel 80 mg/m2 with ipatasertib 400 mg or placebo (days 1-21 every 28 days) for 12 weeks before surgery. Co-primary end points were pathologic complete response (pCR) rate (ypT0/TisN0) in the intention-to-treat (ITT) and immunohistochemistry phosphatase and tensin homolog (PTEN)-low populations. Secondary end points included pCR rate in patients with PIK3CA/AKT1/PTEN-altered tumors and pre-surgery response rates by magnetic resonance imaging (MRI).

RESULTS

pCR rates with ipatasertib versus placebo were 17% versus 13%, respectively, in the ITT population (N = 151), 16% versus 13% in the immunohistochemistry PTEN-low population (N = 35), and 18% versus 12% in the PIK3CA/AKT1/PTEN-altered subgroup (N = 62). Rates of overall and complete response (CR) by MRI favored ipatasertib in all three populations (CR rate 39% versus 9% in the PIK3CA/AKT1/PTEN-altered subgroup). Ipatasertib was associated with more grade ≥3 adverse events (32% versus 16% with placebo), especially diarrhea (17% versus 1%). Higher cycle 1 day 8 (C1D8) immune score was significantly associated with better response only in placebo-treated patients. All ipatasertib-treated patients with low immune scores and a CR had PIK3CA/AKT1/PTEN-altered tumors.

CONCLUSIONS

Adding ipatasertib to 12 weeks of paclitaxel for early TNBC did not clinically or statistically significantly increase pCR rate, although overall response rate by MRI was numerically higher with ipatasertib. The antitumor effect of ipatasertib was most pronounced in biomarker-selected patients. Safety was consistent with prior experience of ipatasertib-paclitaxel. A T-cell-rich environment at C1D8 had a stronger association with improved outcomes in paclitaxel-treated patients than seen for baseline tumor-infiltrating lymphocytes. This dependency may be overcome with the addition of AKT inhibition, especially in patients with PIK3CA/AKT1/PTEN-altered tumors.

CLINICALTRIALS.GOV

NCT02301988.

Abstract P2-08-19: Exploratory biomarker analyses of FAIRLANE, a double-blind placebo (PBO)-controlled randomized phase II trial of neoadjuvant ipatasertib (IPAT) + paclitaxel (PAC) for early triple-negative breast cancer (TNBC)

Background: The oral AKT inhibitor IPAT is being evaluated in cancers with a high prevalence of PI3K/AKT pathway activation. In the PBO-controlled randomized phase II FAIRLANE trial (NCT02301988), adding IPAT to PAC as neoadjuvant therapy for TNBC led to a numerical increase in pathologic complete response (pCR) in unselected patients (17.1% vs 13.3%), with a greater treatment effect in patients with PIK3CA/AKT1/PTEN-altered tumors (17.9% vs 11.8%). The addition of IPAT also led to an increase in complete response (CR) by MRI (27.6% vs 13.3%) that was enhanced in patients with PIK3CA/AKT1/PTEN-altered tumors (39.3% vs 8.8%) [Oliveira, AACR 2018]. We report an exploratory analysis performed to provide better understanding of potential biomarkers for response.

Methods: Pretreatment tumor samples were evaluated for genomic alterations using the FoundationOne® (Foundation Medicine) assay (n=144) and gene expression by RNA-Seq (n=92). Samples were classified into TNBC subtypes based on the method developed by Lehmann and Pietenpol [Lehmann, J Clin Invest 2011]. Tumor-infiltrating lymphocytes (TILs) were quantified using the Salgado method [Salgado, Ann Oncol 2015] (n=135).

Results: Of 62 patients (43%) with PIK3CA/AKT1/PTEN-altered tumors, 21 had an activating mutation in PIK3CA or AKT1 and 47 had an alteration in PTEN (6 [3 in each arm] had both PIK3CA mutation and PTEN alteration). Although only 3 patients with PIK3CA/AKT1-mutant tumors achieved a pCR, there was an increased rate of MRI CR with the addition of IPAT to PAC [Table]. In patients with PTEN alterations, both pCR rate and MRI CR rate were increased with IPAT. In patients treated with PBO + PAC, all 4 pCR patients evaluable by RNA-Seq were of the immunomodulatory (IM) subtype. However, in the IPAT + PAC arm, pCRs were also seen in patients with basal-like 1 (BL-1), mesenchymal (M), and mesenchymal stem-like (MSL) subtypes. Consistent with this observation, in the PBO + PAC arm, samples from patients achieving a pCR had significantly higher levels of stromal TILs than those from patients who did not have a pCR, while no difference was observed in the IPAT + PAC arm.

Response, n (%)PIK3CA/AKT mutation (n=21)PTEN alteration (n=47) IPAT + PAC (n=11)PBO + PAC (n=10)IPAT + PAC (n=21)PBO + PAC (n=26)pCR1 (9%)2 (20%)4 (19%)3 (12%)CR by MRI5 (45%)1 (10%)8 (38%)2 (8%)

Conclusions: This retrospective exploratory biomarker analysis of the phase II FAIRLANE trial of neoadjuvant IPAT for TNBC provides insight into the potential heterogeneity of response and resistance to taxane therapy. The results also hint that response to PAC alone is dependent on baseline immune infiltration and that this dependency might be relieved with the addition of AKT inhibition.

Citation Format: Wongchenko MJ, Oliveira M, Saura C, Nuciforo P, Calvo I, Andersen J, Passos Coelho JI, Gil Gil M, Bermejo B, Patt DA, Ciruelos E, Singel SM, Maslyar DJ, Xu N, de la Peña L, Baselga J, Gendreau S, Isakoff SJ. Exploratory biomarker analyses of FAIRLANE, a double-blind placebo (PBO)-controlled randomized phase II trial of neoadjuvant ipatasertib (IPAT) + paclitaxel (PAC) for early triple-negative breast cancer (TNBC) [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P2-08-19.

Abstract OT3-02-05: CORALLEEN: A phase 2 clinical trial of chemotherapy or letrozole plus ribociclib as neoadjuvant treatment for postmenopausal patients with luminal B/HER2-negative breast cancer

Background: Dysregulation of cyclin D-CDK4/6-Rb pathway is associated with endocrine resistance in hormone receptor–positive (HR+) breast cancer. Recently, a CDK4/6 inhibitor has shown unprecedented efficacy in metastatic disease, leading to its regulatory approval. Several others are currently in clinical development for the management of HR+ breast cancer in the early and advanced settings. However, it is vital to gain insights into the molecular and biological effects of this class of agents and could identify patients who can benefit the most, delaying or avoiding the use of chemotherapy.The neoadjuvant setting provides an ideal scenario to carry out these investigations. Hence, we propose to conduct an exploratory study to evaluate the biological effects and the efficacy of ribociclib in patients with primary luminal B tumors. We hypothesize that the combination of ribociclib plus letrozole may offer clinical benefit in the preoperative setting. Methods: This is a parallel, multicenter, two-arm, randomized exploratory study in postmenopausal women with primary operable HR+/HER2-negative Luminal B breast cancer designed to evaluate the clinical benefit of ribociclib plus letrozole. Eligibility includes stage I-III operable breast cancer, Luminal B by PAM50, ECOG 0-1. They will be randomized 1:1 to receive either six 28-days cycles of ribociclib (600mg; 3-weeks-on/1-week-off) plus daily letrozole (2.5mg) or chemotherapy: four cycles of AC (doxorubicin 60 mg/m2, cyclophosphamide 600 mg/m2 every 21 days) followed by weekly paclitaxel during 12 weeks. Baseline, Day 15 on-treatment, and surgical specimens will be collected for molecular characterization and evaluation of response (decrease in Ki67, change to ROR low disease) The primary endpoint is the rate of Residual Cancer Burden (RCB) per MD Anderson Cancer Center procedures. A rate of RCB 0 and 1 score at surgery, with a rank between 20% to 25% with 47 evaluable patients by group of treatment will offer a precision between 11.5% and 12.4%, respectively (95%CI). Ninety-four patients will be enrolled in 21 sites across Spain. The trial was activated in July 2017. As of June 2018, 78 patients have been recruited.

Citation Format: Gavila J, Saura C, Oliveira M, Ciruelos E, Gonzalez X, de la Peña L, Bermejo de las Heras B, Muñoz M, Fernandez P, Villagrasa P, Ortega V, Lopez R, Celiz P, Pascual T, Prat A. CORALLEEN: A phase 2 clinical trial of chemotherapy or letrozole plus ribociclib as neoadjuvant treatment for postmenopausal patients with luminal B/HER2-negative breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr OT3-02-05.

Abstract P4-21-05: Neoadjuvant non-pegylated liposomal doxorubicin plus paclitaxel, trastuzumab and pertuzumab in patients with HER2+ breast cancer – Final results of the SOLTI OPTI-HER HEART study

INTRODUCTION

Targeting HER2 by dual blockade with trastuzumab (T) and pertuzumab (P) in a taxane-based regimen is an active neoadjuvant treatment (NAT) of HER2+ early breast cancer (EBC). Addition of an anthracycline could further enhance this response, but potential cardiac toxicity is a concern. The Opti-HER HEART trial (NCT01669239) aims to optimize neoadjuvant treatment while minimizing cardiac risk, by combining T+P with a taxane and non-pegylated liposomal doxorubicin (NPLD).

MATERIAL AND METHODS

Phase II open-label, single-arm study of six 21-day cycles of NPLD (50mg/m2 D1), paclitaxel (80mg/m2 D1,8,15), T (4mg/kg C1D1, followed by 2mg/kg weekly), and P (840mg C1D1, followed by 420mg C2-6D1) as NAT for patients (pts) with stage II-IIIB HER2+ BC. Primary objective was to evaluate cardiac safety of the combination, measured by the incidence of type A (symptomatic congestive heart failure ) or type B [asymptomatic reduction of Left Ventricular Ejection Fraction (LVEF) value: ≥10% absolute decrease and LVEF<50%, LVEF<40% or any absolute decrease ≥20%] events, during NAT. Eighty-three pts were required to reject with 80% confidence the null hypothesis that the combination increases the incidence of cardiac events above the historical control of 18% (3% type A; 15% type B).

RESULTS

Between June 2013 and January 2015, 83 pts with HER2+ EBC (stage II 78%, stage III 22%) and adequate cardiac function (LVEF≥55%) were enrolled. Mean age was 50 years, N+ 47%, hormone receptor (HR) positive 71% and median baseline LVEF 66%. Eighty-five percent of pts completed 6 cycles of NAT, whereas 15% discontinued NAT due to toxicity. Adverse events (AEs) leading to dose adjustments/temporary interruptions and discontinuation of at least 1 drug occurred in 70% and 21% of pts, respectively. Primary objective was met with an incidence of cardiac events during NAT of 4% (95%CI 1-10, 3pts, all type B). Cardiac events until study completion (1 year) were 8% (all type B). All (but 2 cases with no follow-up data) were reversible and only 1 pt presented an asymptomatic LVEF<40%. Neutropenia (45%) was the most frequent hematological toxicity (G3/4 34%; febrile neutropenia 6%), less frequent in the 71% of pts that received primary G-CSF prophylaxis (G3/4 25% vs. 67%). Common non-hematological toxicities were diarrhea (74%; G3 7%), asthenia (78%; G3 11%) and neurotoxicity (52%; G3/4 10%). Pathological complete response (pCR) in breast+axilla (ypT0/is ypN0) was 60% (87% in HR-) and 69% in breast (91% in HR-).

 TOTALHR-HR+% ypT0/is (95% CI)69 (58-79)91 (72-99)61 (47-74)% ypT0/is ypN0 (95% CI)60 (46-71)87 (66-97)50 (36-64)

CONCLUSIONS

The neoadjuvant combination of T+P, paclitaxel and NPLD does not increase the risk for cardiac events in HER2+ BC pts. Since cardiac toxicities may present later, long-term cardiac monitoring is essential. Efficacy in terms of pCR was remarkable, being higher to historical values of combinations with dual anti-HER2 blockade and one of the highest reported among HR-HER2+ BC. This regimen administered with primary G-CSF prophylaxis and cardiac function monitoring may be an effective and secure option for early and locally advanced HER2+ pts with good cardiac function.

Citation Format: Gavilá J, Perez-Garcia J, Calvo I, Ciruelos E, Muñoz M, Virizuela JA, Ruiz I, Andrés R, Morales S, Perelló A, Sánchez P, Garcia-Saenz JA, Quero Guillen JC, González-Santiago S, Garau Llinas I, González-Martín A, Cantos Sánchez de Ibargüen B, Zaragoza K, de la Peña L, Llombart-Cussac A, Oliveira M. Neoadjuvant non-pegylated liposomal doxorubicin plus paclitaxel, trastuzumab and pertuzumab in patients with HER2+ breast cancer – Final results of the SOLTI OPTI-HER HEART study [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P4-21-05.

Radiotherapy Learning in Medical Undergraduate Courses

Approximately 60 % of all cancer patients receive radiotherapy as a component of their treatment. Radiation Oncology concepts, specifically, are not formally introduced to students in most traditional school curricula until their clinical rotations or may only be included as an optional elective during the core clinical clerkships. The aim of this study is to determine whether the teaching of Radiation Oncology by radiation oncologists, in the third year, in block diagnostic and therapeutic procedures, is helpful for student training and changes their attitude towards the specialty. We administered a pre-test and post-test examination of the concepts in general radiation oncology, radiation physics, radiobiology, breast cancer and their opinion to the third year medical students. The 10-question, multiple choice tests were administered before starting the lessons and when they finished the course. Of the 130 third year students, 95 (73.07 %) participated in the pre-test and post-test analysis. For the entire cohort, improvement was seen in all questions except one regarding physics. A statistically significant improvement (p < 0.005) was seen in the question regarding the aspects of general radiotherapy, radiobiology, acute and after-effects of radiation and the management of early-stage breast cancer. With an adequate methodology, third year students can learn aspects of Radiation Oncology.

Abstract S5-01: Whole exome sequencing of pre-treatment biopsies from the neoALTTO trial to identify DNA aberrations associated with response to HER2-targeted therapies

Background: We examined if alterations in nucleic acid variants, genes, pathways, and overall mutational load and clonal entropy are associated with pathologic complete response (pCR) and survival after neoadjuvant anti-HER2 therapies in the NeoALTTO trial.

Methods: Whole exome sequencing was performed of 203 baseline biopsies with outcome information. The mean nucleotide coverage was 150x with &gt;90% of target bases showing &gt; 30x coverage in &gt; 99% of samples. Somatic mutations were called by MuTect and indels by Strelka, using pooled reference normal DNA. Significantly mutated genes (FDR&lt;10%) were identified by MutSigCV. Mutations in 714 canonical biological pathways were assessed and mutational load and genome clonal entropy (MATH) were calculated. Association with pCR and survival were evaluated by logistic regression adjusted for ER status and Cox-proportional hazards regression.

Results: Only 12 genes had mutation rates significantly above background and among these only PI3KCA was associated with lower pCR rate (OR=0.42, p=0.019). Genes with somatic mutations in more than 10 patients were also assessed, but none were associated with pCR or survival. Clonal entropy or adjusted mutation load also did not correlate with response. Mutations in 33 pathways showed significant association with response in the entire cohort. In the trastuzumab arm, 23 of the 33 pathways showed an association with response but none was independent of PIK3CA mutation. We constructed "PIK3CA-gene network" that included all unique genes (n=439) from theese 23 pathways. Of the 66 patients in the trastuzumab arm, 50 carried at least one mutation in one of the 439 genes and among these only 2 achieved pCR (4%) compared to 9 of 16 pCR (56%) among the wild type (OR=0.035; p &lt; 0.001). The same genes/mutations had little impact on pCR in the lapatinib arm (pCR 20%). In the lapatinib arm, mutations in 3 pathways conferred higher probability of pCR. The "Regulation of RhoA activity" pathway, had the most significant association with pCR in the entire cohort (OR=3.77, p=0.0009) and in the lapatininb (pCR 67% vs 17%, OR=14.8, p=0.008) and lapatinib + trastuzumab (OR=3.0, p=0.06) arms, but not in the trastuzumab arm (OR=1.4, p=0.7). Event free and overall survival were also significantly higher in patients who had mutations in this pathway. Twenty seven of the 48 genes in this pathway had mutations affecting 33 patients but different genes were affected in different individuals.

Conclusions: There are no high frequency recurrent single mutations associated with response to HER2-targeted therapies, other than PIK3CA. We identified several biological pathways, including RhoA activity, and a network of PIK3CA associated genes that are significantly associated with response when affected by mutations, however, different genes are mutated in different individuals.

Citation Format: Pusztai L, Shi W, Jiang T, Nuciforo P, Holmes E, Harbeck N, Sotiriou C, Rimm D, Hatzis C, de la Peña L, Armour A, Piccart-Gebhart M, Baselga J. Whole exome sequencing of pre-treatment biopsies from the neoALTTO trial to identify DNA aberrations associated with response to HER2-targeted therapies. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr S5-01.

Benefit to neoadjuvant anti-human epidermal growth factor receptor 2 (HER2)-targeted therapies in HER2-positive primary breast cancer is independent of phosphatase and tensin homolog deleted from chromosome 10 (PTEN) status

BACKGROUND

Assessment of phosphatase and tensin homolog deleted from chromosome 10 (PTEN) might be an important tool in identifying human epidermal growth factor receptor 2 (HER2)-positive breast cancer patients unlikely to derive benefit from anti-HER2 therapies. However, studies to date have failed to demonstrate its predictive role in any treatment setting.

PATIENTS AND METHODS

Prospectively collected baseline core biopsies from 429 early-stage HER2-positive breast cancer patients treated with trastuzumab, lapatinib, or their combination in the Neo-ALTTO study were stained using two anti-PTEN monoclonal antibodies (CST and DAKO). The association of PTEN status and PI3K pathway activation (defined as either PTEN loss and/or PIK3CA mutation) with total pathological complete response (tpCR) at surgery, event-free survival (EFS), and overall survival (OS) was evaluated.

RESULTS

PTEN loss was observed in 27% and 29% of patients (all arms, n = 361 and n = 363) for CST and DAKO, respectively. PTEN loss was more frequently observed in hormone receptor (HR)-negative (33% and 36% with CST and DAKO, respectively) compared with HR-positive tumours (20% and 22% with CST and DAKO, respectively). No significant differences in tpCR rates were observed according to PTEN status. PI3K pathway activation was found in 47% and 48% of patients (all arms, n = 302 and n = 301) for CST and DAKO, respectively. Similarly, tpCR rates were not significantly different for those with or without PI3K pathway activation. Neither PTEN status nor PI3K pathway activation were predictive of tpCR, EFS, or OS, independently of treatment arm or HR status. High inter-antibody and inter-observer agreements were found (>90%). Modification of scoring variables significantly affected the correlation between PTEN and HR status but not with tpCR.

CONCLUSION

These data show that PTEN status determination is not a useful biomarker to predict resistance to trastuzumab and lapatinib-based therapies. The lack of standardization of PTEN status determination may influence correlations between expression and relevant clinical end points.

CLINICAL TRIALS

This trial is registered with ClinicalTrials.gov: NCT00553358.

Abstract OT1-2-04: PAM50 HER2-enriched (HER2E) phenotype as a predictor of early-response to neoadjuvant lapatinib plus trastuzumab in stage I to IIIA HER2-positive breast cancer

Background: The efficacy of trastuzumab in different regimens and settings has been well established, including its benefit as neoadjuvant therapy for early HER2-positive disease. Combinations of two different anti-HER2 therapies without chemotherapy have generated great expectations. However, it is unclear which group of patients benefits the most from this strategy. Within HER2-positive breast cancer, the PAM50 assay identifies a HER2-Enriched (HER2-E) intrinsic subtype characterized by high activation of the EGFR/HER2 pathway and low expression of luminal-related genes, and therefore should obtain the greatest benefit from anti-HER2 therapy.

Trial Design: This non-randomized, open-label, multicentric phase II translational research study will evaluate the ability of the PAM50 HER2-E subtype to predict pathological complete response (pCR) to dual HER2 blockade with lapatinib and trastuzumab for a total of 18 weeks. Patients with hormone receptor (HR)-positive disease will also receive endocrine therapy (letrozol or tamoxifen).

Eligibility Criteria: Untreated, histologically confirmed invasive breast carcinoma eligible for definitive surgery (stage I-IIIA), HER2-positive invasive breast cancer by central assessment, premenopausal or postmenopausal, ECOG performance status of 0 or 1, adequate organ function and baseline LVEF &gt;50% measured by echocardiography or MUGA scan.

Specific Aims: The primary objective is to evaluate the ability of the PAM50 assay to predict pCR in the breast at the time of surgery. Secondary objectives are to (1) assess the correlation of HER2-E with pCR in the breast and axilla, (2) assess the correlation of HER2-E with Residual Cancer Burden (RCB) (3) evaluate the gene expression changes from Day 0 to Day 14 and the correlations with Ki67-IHC at Day 14, (4), identify additional gene expression signatures predictive of pCR, and (5) evaluate safety and tolerability.

Statistical Methods: The statistical plan is based on the assumption that breast pCR rate will be 35.0% for HER2-E tumors and 8.0% for non-HER2E. The study will have a 95% power with a significance level of 5% (two-sided) and an assumed drop-out rate of 15%. Biomarker Analyses: Baseline, 14-day treated and post-treatment (surgical) formalin–fixed, paraffin–embedded tissues will be obtained. The expression of 547 genes will be explored with the nCounter platform. Subtype will be identified using the PAM50 predictor (Parker et al. J Clin Oncol 2009). Ki-67-IHC will also be evaluated on pre-treatment and Day-14 samples.

Target Accrual: 150 patients with a maximum of 75 HR-positive patients across Spain and Portugal. Patient enrollment will begin in July 2013.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr OT1-2-04.

Reordering of the ridge patterns of a stochastic electromagnetic field by diffraction due to an ideal slit

We study the behavior of scarlets of a stochastic radiation field of fixed frequency in the presence of a slit pierced on an infinitely thin metallic screen of ideal conductivity. Our methodology involves the exact solution of the Maxwell equations with appropriate boundary conditions, the only approximations being those due to the numerical procedure. Our numerical simulations show that the field is unfolded into two components, a dominant one that is disordered and a weaker one that is ordered. The former still presents scarlets although modified, while the latter exhibits a pattern of perfectly coherent diffraction. Due to the dominant character of the disordered component, the general appearance of the scattered field is stochastic; however, an underlying order exists. Our results confirm, thus, a novel effect suggested previously in the context of stochastic electrodynamics.

Methotrexate cytotoxicity on MCF-7 breast cancer cells is not altered by exposure to 25 Hz, 1.5 mT magnetic field and iron (III) chloride hexahydrate

The action of electromagnetic fields (EMF) on different pathways related to cell physiology, proliferation, toxicity of chemicals, gene expression, etc., are currently being investigated although the results are still not conclusive and even conflicting. In laboratory and animal studies, EMF has been found to produce a great variety of effects such as: increase in ornithine decarboxylase activity in breast, increase in beta-galactosidase gene expression and oncogene transcription after exposure to 50/60 Hz. Animal studies have shown that the use of EMF can enhance drug delivery across biological barriers (rat abdominal skin), using benzoic acid as the drug candidate. It has been reported by different authors that pulsed EMF (PEMF) can produce alterations in antineoplastic drugs potency. In the present study, we investigated the effects of PEMF on methotrexate cytotoxicity in MCF-7 breast cancer cells and the effects with simultaneous exposure to FeCl3. The data presented in the current report indicate that PEMF (25 Hz, 1.5 mT) do not induce modulation of the action of methotrexate (with and without iron-III) in MCF-7 cells when they are exposed to PEMF for 2 h/day during 3 days.

Influence of 1 and 25 Hz, 1.5 mT magnetic fields on antitumor drug potency in a human adenocarcinoma cell line

The resistance of tumor cells to antineoplastic agents is a major obstacle during cancer chemotherapy. Many authors have observed that some exposure protocols to pulsed electromagnetic fields (PEMF) can alter the efficacy of anticancer drugs; nevertheless, the observations are not clear. We have evaluated whether a group of PEMF pulses (1.5 mT peak, repeated at 1 and 25 Hz) produces alterations of drug potency on a multidrug resistant human colon adenocarcinoma (HCA) cell line, HCA-2/1(cch). The experiments were performed including (a) exposures to drug and PEMF exposure for 1 h at the same time, (b) drug exposure for 1 h, and then exposure to PEMF for the next 2 days (2 h/day). Drugs used were vincristine (VCR), mitomycin C (MMC), and cisplatin. Cell viability was measured by the neutral red stain cytotoxicity test. The results obtained were: (a) The 1 Hz PEMF increased VCR cytotoxicity (P < 0.01), exhibiting 6.1% of survival at 47.5 microg/ml, the highest dose for which sham exposed groups showed a 19.8% of survival. For MMC at 47.5 microg/ml, the % of survival changed significantly from 19.2% in sham exposed groups to 5.3% using 25 Hz (P < 0.001). Cisplatin showed a significant reduction in the % of survival (44.2-39.1%, P < 0.05) at 25 Hz and 47.5 microg/ml, and (b) Minor significant alterations were observed after nonsimultaneous exposure of cells to PEMF and drug. The data indicate that PEMF can induce modulation of cytostatic agents in HCA-2/1(cch), with an increased effect when PEMF was applied at the same time as the drug. The type of drug, dose, frequency, and duration of PEMF exposure could influence this modulation.

[Varicella pneumonia in the adult: study of 22 cases]

BACKGROUND

Retrospective study of the varicella pneumonia in adults with clinical, therapeutic and evolutive features in 22 patients in the last 5 years.

MATERIAL AND METHODS

The diagnosis was established by clinical and radiologic criteria in the course of varicella infection. The antecedents of pregnancy, smoking habit, previous contact with patients with varicella and underlying disease were evaluated.

RESULTS

Twenty-two patients (14 males and 8 women: mean age 31 years. range: 22-40) were included in the study. None of them were immunocompromised, 16 (72.7%) have had previous contact with varicella patients. 19 (86.3%) were heavy smokers and none of the female patients was pregnant. All patients had fever and exanthem, cough had 20 (90.9%) dyspnea 16 (72.7%), chest pain 9 (40.9%) and hemoptysis 5 (22.7%). Only two patients showed pO2 < 60 mmHg. Chest X-ray revealed an interstitial pattern in 14 cases (63.3%), and micronodular in 8 (36.3%). All patients received treatment with intravenous acyclovir. Three patients (13.6%) were admitted to the Intensive Care Unit due to respiratory insufficiency, needing mechanical ventilation one of them (4.5%). Another three developed failure renal reversible associated with acyclovir. All patients had a favourable clinical course.

CONCLUSIONS

We believe, that early, aggressive use of intravenous acyclovir in adult varicella pneumonia may be lifesaving, preventing progressive respiratory failure and reducing the high mortality rate of the disease. Therapy with corticosteroids should be considered in addition to antiviral therapy in patients with severe varicella pneumonia. While oral acyclovir chemoprophylaxis is probably beneficial in populations with chicken pox.

Growth modification of human colon adenocarcinoma cells exposed to a low-frequency electromagnetic field

The influence of variable low-intensity, low-frequency electromagnetic fields on culture cells is investigated. Human colon adenocarcinoma cells were exposed to a rectangular and variable magnetic field (1 and 25 Hz; 1.5 mT peak). Cultures were exposed to a dose for 15 and 360 minutes, and after 24 hours incubation, cell viability was measured with neutral red stain. The group treated for 15 minutes showed a statistically significant increase in cell growth with 1 Hz (p < 0.002) and 25 Hz (p < 0.003). In contrast, a significant decrease in cell growth was found in those cultures treated with 1 Hz for 360 minutes (p < 0.02). The effects reported could be influenced by the magnetic field frequency and the exposure time.

Altered processing of precursor transcripts and increased levels of the subunit I of mitochondrial cytochrome c oxidase in Syrian hamster fetal cells initiated with ionizing radiation

Treatment of Syrian hamster fetal cells (SHFC) with ionizing radiation resulted in the establishment of 21 transformed cell lines. Relative to unirradiated controls, cells from early post-irradiation passages (p.3) showed marked morphologic alterations, increased growth rate and extended life span, and they were contact-inhibited and not tumorigenic in nude mice, although they became tumorigenic after extended passaging in culture (p. > 30). Differential mRNA display analyses of normal cells (84-3) and radiation-initiated cell lines at early passage showed that the latter contained increased steady-state levels of the precursor (4-fold) and mature (1.7-fold) transcripts of the mitochondrial (mt) gene encoding the subunit I of cytochrome c oxidase (CO I). These molecular alterations were consistently observed in 57% of the irradiated (HDR) cell lines, and were stably maintained during continuous passaging (p. > 50). Further analyses of one of these cell lines (HDR-3) demonstrated that the accumulation of CO I precursor transcripts was the result of mRNA stabilization and increased replication and/or amplification of the mt DNA. Radiation-initiated cells contained elevated levels of the CO I protein, showed a 75% reduction in cytochrome c oxidase (CO) activity, and a 5-fold increase in the concentration of hydrogen peroxide secreted into their culture medium compared with cells with no alterations in CO I mRNA processing. Our findings suggest that alterations in mt CO I processing may play a role in the neoplastic conversion of mammalian cells by ionizing radiation.

Kinetic determination of nortriptyline in pharmaceutical samples by use of photometric and fluorimetric detection

A fast kinetic method is proposed for the photometric and fluorimetric determination of nortriptyline hydrochloride. The method involves measuring the rate of formation of an adduct with 4-chloro-7-nitrobenzofurazan, which exhibits light absorption and fluorescent properties, and the use of a stopped-flow mixing technique, which facilitates application to automatic routine analyses. The reaction rate is measured within only 30 s. The detection limit is 0.12 micrograms ml-1 (photometry) and 0.18 micrograms ml-1 (fluorimetry) and the calibration graph is linear up to 60 micrograms ml-1 in both cases. The precision (as RSD) is less than 1.5%. The proposed method was satisfactorily used for direct analysis of pharmaceutical preparations and a mean recovery near 100% was obtained with both photometric and fluorimetric detection.

Kinetic fluorimetric determination of promethazine by a stopped-flow mixing technique

The oxidation of promethazine to its corresponding fluorescent sulphoxide was used to develop a novel kinetic fluorimetric method for the determination of this drug. The use of a stopped-flow mixing technique makes use of an oxidizing reagent unnecessary because the oxidation is rapidly carried out by dissolved oxygen. The method is simple and fast as it only requires a few seconds to obtain kinetic data which allows ready application to routine analyses. The calibration graph is linear over the range 0.5-80 micrograms ml-1 and the precision (%RSD) is close to 2%. The method was applied to the determination of promethazine hydrochloride in two pharmaceutical preparations.