Enhancing affinity purification of monoclonal antibodies from human serum for subsequent CZE-MS analysis

Due to the separation technique employed, capillary electrophoresis coupled to mass spectrometry (CE-MS) analysis performances are significantly influenced by the chemical composition and the complexity of the sample. In various applications, that impact has prevented the use of CE-MS for the characterization and quantification of proteins in biological samples. Here we present the development and evaluation and a sample preparation procedure, based on affinity purification, for the specific extraction of the monoclonal antibody (mAbs) infliximab from human serum in order to perform subsequent proteolytic digestion and CE-MS/MS analysis. Three distinctive sample preparation strategies were envisaged. In each case, the different steps composing the protocol were thoroughly optimized and evaluated in order to provide a sample preparation addressing the important complexity of serums samples while providing an optimal compatibility with CE-MS/MS analysis. The different sample preparation strategies were assessed concerning the possibility to achieve an appropriate absolute quantification of the mAbs using CE-MS/MS for samples mimicking patient serum samples. Also, the possibility to perform the characterization of several types of post-translational modifications (PTMs) was evaluated. The sample preparation protocols allowed the quantification of the mAbs in serums samples for concentration as low as 0.2 µg·mL-1 (2.03 nM) using CE-MS/MS analysis, also the possibility to characterize and estimate the modification level of PTMs hotspots in a consistent manner. Results allowed to attribute the effect on the electrophoretic separation of the different steps composing sample preparation. Finally, they demonstrated that sample preparation for CE-MS/MS analysis could benefit greatly for the extended applicability of this type of analysis for complex biological matrices.

Unraveling the potential clinical utility of circulating tumor DNA detection in colorectal cancer-evaluation in a nationwide Danish cohort

BACKGROUND

Increasingly, circulating tumor DNA (ctDNA) is proposed as a tool for minimal residual disease (MRD) assessment. Digital PCR (dPCR) offers low analysis costs and turnaround times of less than a day, making it ripe for clinical implementation. Here, we used tumor-informed dPCR for ctDNA detection in a large colorectal cancer (CRC) cohort to evaluate the potential for post-operative risk assessment and serial monitoring, and how the metastatic site may impact ctDNA detection. Additionally, we assessed how altering the ctDNA-calling algorithm could customize performance for different clinical settings.

PATIENTS AND METHODS

Stage II-III CRC patients (N = 851) treated with a curative intent were recruited. Based on whole-exome sequencing on matched tumor and germline DNA, a mutational target was selected for dPCR analysis. Plasma samples (8 ml) were collected within 60 days after operation and-for a patient subset (n = 246)-every 3-4 months for up to 36 months. Single-target dPCR was used for ctDNA detection.

RESULTS

Both post-operative and serial ctDNA detection were prognostic of recurrence [hazard ratio (HR) = 11.3, 95% confidence interval (CI) 7.8-16.4, P < 0.001; HR = 30.7, 95% CI 20.2-46.7, P < 0.001], with a cumulative ctDNA detection rate of 87% at the end of sample collection in recurrence patients. The ctDNA growth rate was prognostic of survival (HR = 2.6, 95% CI 1.5-4.4, P = 0.001). In recurrence patients, post-operative ctDNA detection was challenging for lung metastases (4/21 detected) and peritoneal metastases (2/10 detected). By modifying the cut-off for calling a sample ctDNA positive, we were able to adjust the sensitivity and specificity of our test for different clinical contexts.

CONCLUSIONS

The presented results from 851 stage II-III CRC patients demonstrate that our personalized dPCR approach effectively detects MRD after operation and shows promise for serial ctDNA detection for recurrence surveillance. The ability to adjust sensitivity and specificity shows exciting potential to customize the ctDNA caller for specific clinical settings.

Post-translational modifications comparative identification and kinetic study of infliximab innovator and biosimilars in serum using capillary electrophoresis-tandem mass spectrometry

Despite reports indicating the potential impact of post-translational modifications on the activity of a monoclonal antibody, their prediction or monitoring post-administration remains a challenge. In addition, with the expiration of patents concerning the early generation of mAbs, the production of biosimilars is constantly increasing. Structural differences of biosimilars compared to the innovator product are commonly evaluated for the formulated product in the context of biosimilarity assessment. However, estimating their structural outcome after administration is particularly difficult. Due to the complexity of in vivo studies, there is a need to develop analytical strategies to predict PTMs consequently to their administration and their impact on mAbs potency. Here, we identified and evaluated the modification kinetics of 4 asparagine deamidations and 2 aspartate isomerizations of infliximab innovator product (Remicade®) and two biosimilars (Inflectra® and Remsima®) in vitro using serum incubation at 37 °C. The methodology was based on a bottom-up approach with capillary electrophoresis hyphenated with mass spectrometry analysis for an unequivocal assignment of modified and unmodified forms. 2 asparagines demonstrated a gradual deamidation correlated with incubation time. The specific extraction efficiency was evaluated to determine possible changes in the antigen binding affinity of infliximab with the incubation. Results showed the possibility to achieve an additional aspect concerning biosimilarity assessment, oriented on the study of the structural stability after administration.

Simultaneous quantification and structural characterization of monoclonal antibodies after administration using capillary zone electrophoresis-tandem mass spectrometry

Monoclonal antibodies (mAbs) are demonstrating major success in various therapeutic areas such as oncology and the treatment of immune disorders. Over the past two decades, novel analytical methodologies allowed to address the challenges of mAbs characterization in the context of their production. However, after administration only their quantification is performed and insights regarding their structural evolution remain limited. For instance, clinical practice has recently highlighted significant inter-patient differences in mAb clearance and unexpected clinical responses, without providing alternative interpretations. Here, we report the development of a novel analytical strategy based on capillary zone electrophoresis coupled to tandem mass spectrometry (CE-MS/MS) for the simultaneous absolute quantification and structural characterization of infliximab (IFX) in human serum. CE-MS/MS quantification was validated over the range 0.4-25 µg·mL^-1 corresponding to the IFX therapeutic window and achieved a LOQ of 0.22 µg·mL^-1 (1.5 nM) while demonstrating outstanding specificity compared to the ELISA assay. CE-MS/MS allowed structural characterization and estimation of the relative abundance of the six major N-glycosylations expressed by IFX. In addition, the results allowed characterization and determination of the level of modification of post-translational modifications (PTMs) hotspots including deamidation of 4 asparagine and isomerization of 2 aspartate. Concerning N-glycosylation and PTMs, a new normalization strategy was developed to measure the variation of modification levels that occur strictly during the residence time of IFX in the patient's system, overcoming artefactual modifications induced by sample treatment and/or storage. The CE-MS/MS methodology was applied to the analysis of samples from patients with Crohn's disease. The data identified a gradual deamidation of a particular asparagine residue located in the complementary determining region that correlated with IFX residence time, while the evolution of IFX concentration showed significant variability among patients.

Abstract P1-15-16: Pathological complete response rates with the addition of carboplatin to standard neoadjuvant chemotherapy in a cohort of real–world patients with triple negative breast cancer

Objectives: Addition of carboplatin to standard neoadjuvant chemotherapy (NACT) for triple negative breast cancer (TNBC) remains controversial. There are several randomized trials showing that carboplatin increases the likelihood of achieving pathological complete response (pCR) in TNBC. Patients with TNBC who achieve pCR has been shown to have better disease-free and overall survival. The aim of this study was to asses the impact of adding carboplatin to standard NACT in TNBC in terms of pCR rates and toxicity. Methods:In this cross-sectional study, 252 consecutive patients with primary TNBC who were submitted to neoadjuvant chemotherapy between 2013 and 2018, in a single center, were selected. Patients with biopsy-confirmed TNBC, previously untreated, with clinical stages I-III were included (n=179). Clinical pathological features, pathological response, treatment protocol, and toxicities were analyzed and considered for statistical analysis. Eighty patients treated from 2013 to 2015 received doxorubicin plus cyclophosphamide once every 3 weeks (AC) for four cycles, followed by 12 weeks (wP) or every 3 weeks (P) paclitaxel(AC-T group). Ninety-nine patients, treated from 2015 to 2018 had four cycles of AC followed by wP plus weekly carboplatin (Cb) area under curve (AUC) 1.5-2.0 (AC-TCb group). Pathologic response was determined locally, and pCR was defined as the absence of residual invasive disease with or without ductal carcinoma in situ in the breast and axilla. Results: Data from 179 patients were included in the analysis (AC-T: n=80; AC-TCb: n=99). Patients in AC-TCb group had a median age of 51.7 years vs. 47.4 years in AC-T group, p=0.01. In AC-TCb group 61.6% of patients were postmenopausal vs 43.7% in AC-T group, p=0.03. The distribution of clinical stage in groups AC-TCb and AC-T were as follows: stage I 6.0% vs 0%; stage II 42.4% vs 43.7%; stage III 51.6% vs 56.3%, respectively (p=0.02). In AC-TCbgroup, 34 patients (35.0%) had pCR in comparison to 20 patients (25.0%) on AC-T group (p=0.22). Pathological stage distribution in groups AC-TCb and AC-T were: stage I 24.7% vs 33.7%; stage II 23.7% vs 26.3%; stage III 16.4% vs 15%, respectively (p=0.42). More than 85.0% of patients in AC-TCb group received at least 9 weeks of carboplatin and less than 20.0% required dose reduction due to toxicity.Conclusions: An improved pathological complete response for TNBC patients submitted to standard NACT plus carboplatin was observed. The results are in accordance with previous studies demonstrating that the addition of carboplatin to NACT improves pCR rate in TNBC with a favorable risk to benefit profile. Therefore carboplatin might be a potential component of NACT and should be considered in this context.

Distribution of patients with TNBC submitted to NACT with AC-T and AC-TCb according clinical–pathological characteristicsClinical pathological characteristicsAC-T n= 80AC-TCb n=99pMenopausal  0.03yes3561 no4538 Clinical stage  0.02I06 II3542 III4551 Histologic type  0.25IDC8096 others03 Histologic grade  0.86101 22932 35164 Pathological stage  0.42O2034 I2724 II2123 III1216 pCR  0.22yes2034 no6063 

Citation Format: Ramalho S, Natal RdA, Cardoso Filho C, Xavier MB, da Silva AER, Silva LR, Vasconcelos V, Reinert T, Coelho GP, Silva GRdP, dos Santos CC. Pathological complete response rates with the addition of carboplatin to standard neoadjuvant chemotherapy in a cohort of real–world patients with triple 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 P1-15-16.

Abstract P1-08-27: Advanced stage at diagnosis and worse clinicopathologic features in young woman with breast cancer. A sub-analysis of Brazilian population through the AMAZONA III study (GBECAM 0115)

BACKGROUND: Breast cancer (BC) in young women is uncommon and often more aggressive. There are disparities in terms of screening coverage, diagnostic features and access to optimal treatment among young BC patients worldwide. To better understand this scenario through real world data we performed a sub-analysis of AMAZONA III study. METHODS: The AMAZONA III study (GBECAM 0115) is a prospective registry that included 2950 women newly diagnosed with invasive BC in Brazil during the period of January 2016 to March 2018 within 22 sites. Of them, 2888 patients had valid data regarding age at diagnosis and complete baseline information. For the purpose of comparisons of epidemiologic and clinicopathologic features at the time of diagnosis of BC, patients were divided in two groups: women aged ≤40 years (Group 1) and &gt;40 years (Group 2). Quantitative variables were expressed with mean, while categorical variables were described as their count and percentage and compared using the chi-square test. RESULTS: Of 2888 women, 486 (17%) were ≤40 years of age. No differences were found between ethnicity, performance status, body mass index, personal income, health insurance and family history of cancer between the two groups. Young women had higher educational level (p&lt;0.001), were more involved into a labor activity (p&lt;0.001) and were more frequently married (p&lt;0.001). There were also significant differences regarding nulliparity (p&lt;0.001) and previous use of oral contraceptives (p&lt;0.001). Mode of detection of BC was symptomatic in 73.4% of young group versus 64.5% in older group and screen-detected was only 26.6% vs. 35.5% respectively (p&lt;0.001). Table 1 describes clinicopathological characteristics of the two groups. Young women presented more frequently with stage III,T3/T4, Grade 3 tumors and HER-2 positive, Luminal B and triple negative subtypes. Women older than 40 years had more stage I, Luminal A and Grade 1/2 tumors. CONCLUSION: Brazilian women under the age of 40 have unfavorable clinicopathological features of BC at diagnosis with more aggressive subtypes and advanced stage compared with older women. No differences in socioeconomic and ethnical aspects were found but a higher percentage of young women had symptomatic detection of BC which could explain the later stage of disease at diagnosis. Young women were economically active and the majority married which highlights the socioeconomic impact of this disease in Brazil.

Breast cancer features by age groups at diagnosis in Brazilian women.InformationGroup 1 (≤40 years)Group 2 (&gt; 40 years)p-valueN: 2888486 (16.83%)2402 (83.17%) Stage at diagnosis  p&lt; 0.001I76 (19.2%)541 (27.8%) II156 (39.4%)816 (41.9%) III146 (36.8%)489 (25.1%) IV19 (4.6%)101 (5.2%) Tumor size  p&lt; 0.001T1114 (27.1%)749 (36.9%) T2141 (33.6%)764 (37.6%) T3101 (24.1%)282 (13.9%) T464 (15.2%)235 (11.6%) Tumor grade  p &lt; 0.001Grade 146 (10.7%)381 (17.9%) Grade 2198 (46.2%)1150 (52.0%) Grade 3185 (43.1%)641 (30.1%) Molecular Subtype  p &lt; 0.001Luminal A106 (30.6%)957 (51.3%) Luminal B - HER 2 negative55 (15.8%)212 (11.4%) Luminal B- HER 2 positive79 (22.8%)298 (16.0%) HER 2 positive27 (7.8%)135 (7.2%) Triple negative80 (23.0%)264 (14.1%) 

Citation Format: Franzoi MA, Rosa D, Barrios C, Bines J, Cronemberger E, Queiroz G, Cordeiro de Lima VC, Junior R, Couto J, Emerenciano K, Resende H, Crocamo S, Reinert T, Van Evyl B, Neron Y, Dybal V, Lazaretti N, Costamilan RdC, de Andrade D, Mathias C, Zerwes Vacaro G, Borges G, Silva K, Werutsky G, Morelle A, Sampaio Filho CA, Mano M, Zaffaroni F, Simon S, Liedke PE. Advanced stage at diagnosis and worse clinicopathologic features in young woman with breast cancer. A sub-analysis of Brazilian population through the AMAZONA III study (GBECAM 0115) [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 P1-08-27.

Abstract P4-12-01: Not presented

This abstract was not presented at the conference.

Citation Format: Werutsky G, Villareal-Garza C, Moreno HG, Cartagena AA, Campos-Gomez S, Reyes RO, Lence JJ, Liedke P, Reinert T, Binotto M, Dybal V, Martinez-Mesa J, Freitas RD, Nunes Filho PR, Zaffaroni F, Barrios CH. Not presented [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 P4-12-01.

Abstract P1-08-29: Current status of clinical and pathological characteristics of breast cancer patients in Brazil: Results of the AMAZONA III study (GBECAM 0115)

BACKGROUND

Breast cancer (BC) is the most common tumor in women in Brazil with about 60 thousand new cases estimated per year. In low and middle-income countries, patients with BC are diagnosed with more advanced stages as compared with high-income countries. In Brazil, disparities in access to new therapies are recognized; previous data suggests worse survival of BC patients treated in the public system. The aim of AMAZONA III study (GBECAM 0115) is to describe the current status of BC care in Brazil. Here we report patients data at baseline.

METHODS

The AMAZONA III is a prospective BC registry that included women 18 years or older with newly diagnosed stage I to IV BC from 22 sites in Brazil in the period of January 2016 to March 2018. All patients provided written informed consent; data was collected from interview and medical charts, comprising clinical-demographic variables, initial treatment and a planned follow-up for 5 years. BC subtypes were defined by hormone receptor (HR) expression, HER2 status and grade according to von Minckwitz G. et al 2012. Here we present a descriptive analysis of the patients' baseline characteristics. Continuous variables are shown as mean (standard-deviation) and categorical variables by its absolute and relative frequencies. The study is registered in clinicaltrials.gov NCT02663973.

RESULTS

A total of 2950 patients were included in the study. Median age at diagnosis was 53 years old (8.4% &lt;= 35 years, 34.8% 36-50 years, 56.8% &gt; 50 years), 58.6% were white, 34.4% had brown skin-color, 83% had children before BC diagnosis (median of 1 child/patient) and 63.1% had public health insurance. In terms of method of detection 34% were screen-detected whereas 66% were symptomatic, the last was even higher (70%) in patients in younger than 50 years. The distribution of BC stage at diagnosis was I (26.4%), II (41.6%), III (27%) and IV (5%). The most common histologies were ductal (80.9%) and lobular carcinoma (6.9%). The pathological characteristics were HR positive in 78.0%, HER-2 positive in 23.4% and grade 2 in 51%. BC subtypes were as follows: Luminal A 48%, Luminal B 12%, Luminal HER2 positive 17%, Non-luminal HER2 positive 7.3% and Triple negative 15.5%.

DISCUSSION

Breast cancer is diagnosed at an earlier age among Brazilian patients. The majority of patients were detected through symptomatic BC and therefore a significant proportion is still diagnosed in stages III and IV. Among other factors, these findings could have a significant impact in treatment outcomes. Further analysis of this large cohort of patients will help to identify other important elements and direct future strategies for breast cancer control.

TRIAL REGISTRY: NCT02663973

KEYWORDS: Breast Cancer; Epidemiology; Treatment; Brazil

Citation Format: Rosa D, Barrios C, Bines J, Werustky G, Cronemberger E, Queiroz GS, Lima VC, Freitas-Júnior R, Couto J, Emerenciano K, Resende H, Crocamo S, Reinert T, Van Eyil B, Néron Y, Dybal V, Lazaretti N, Costamilan RC, Andrade DA, Mathias C, Vacaro GZ, Borges G, Torres KL, Morelle A, Sampaio Filho CA, Mano M, Zaffaroni F, Simon S. Current status of clinical and pathological characteristics of breast cancer patients in Brazil: Results of the AMAZONA III study (GBECAM 0115) [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 P1-08-29.

Abstract P6-08-24: Reproductive status and clinical pathological characteristics of young women diagnosed with breast cancer in Latin America: LACOG 0414 study

BACKGROUND

Approximately 7% of women diagnosed with breast cancer (BC) are under 40 years old. Chemotherapy may adversely affect ovarian function therefore fertility is an issue to be addressed for these patients. Patients with cancer in Latin America have limited access to fertility preservation. However age at first birth in women from Latin America is lower than in developed country and the needs of fertility preservation may be different from developed countries. The aim of the present study was to describe the reproductive status and clinical pathological features of young women diagnosed with BC in Latin America.

METHODS

LACOG 0414 is a prospective registry in Latin America which included young patients with &lt; 40 years old with diagnosis of BC and indication of (neo) adjuvant chemotherapy. Demographic data, reproductive status and clinical pathological information were retrieved from patients` medical charts. This study was approved by local ethics committees and regulatory authorities.

RESULTS

A total of 343 patients (pts) from 19 different sites distributed in 4 Latin American countries were included: Brasil (N=132 pts), Mexico (N=112 pts), Peru (N=83 pts) and Cuba (N=16 pts). The mean age at BC diagnosis was 34.02 (±4.17) years (14% had &lt; 30 years, 41% had 30-35 years and 44% had 36-40 years). From all included patients, 245 (71.42%) already had children at the time of BC diagnosis. From those the median number of children per women was 2 (range 1–6). The probability of having children at the time of diagnosis was significantly higher with increased age, being as high as 80% in those aged between 36 and 40 years old. There was no difference in terms of having a child at BC diagnosis within the 4 countries, by stage at diagnosis or per breast cancer subtypes.

In terms of educational level, approximately 8% of patients were Illiterate and only 40% had university degree. Stages at BC diagnosis were the following: 12% stage I, 49% stage II, 35% stage III and 3% stage IV. The distribution of BC subtypes was: luminal 48%, HER2-positive 29% and triple negative 23%.

CONCLUSION

To our knowledge, this is the first study describing reproductive status of young patients diagnosed with BC in Latin America. Despite the lack of access to fertility preservation programs in the region, we found that a high number of patients had children at diagnosis of BC. Considering the high prevalence of advanced disease and aggressive subtypes the socioeconomic impact of young BC patients in Latin America needs to be addressed.

Citation Format: Werutsky G, Villarreal-Garza C, Morante Cruz ZD, Debiasi M, Zaffaroni F, Fonseca A, Castro-Sánchez A, Platas A, Gómez Moreno H, Bretel D, Ortiz RM, Reinert T, Dybal V, Liedke P, Barrios C. Reproductive status and clinical pathological characteristics of young women diagnosed with breast cancer in Latin America: LACOG 0414 study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-08-24.

Abstract P4-12-04: Cost-effectiveness analysis of locally advanced estrogen receptor-positive, HER-2 negative breast cancer care using a tailored treatment approach in Brazil

Introduction: Breast cancer is the most common cancer in women worldwide, and 70% of breast cancer deaths occur in women from low-income and middle-income countries. In Brazil there were 14388 deaths due to this disease in 2013 and an estimate of over 58000 new cases in 2016. Neoadjuvant endocrine therapy (NET) is an attractive alternative to Neoadjuvant chemotherapy (NAC) for Hormone Receptor-positive tumors and could be a resources-saving strategy of treatment.

Methods: We built a decision analysis model of breast cancer treatment to compare a NET schema, with response based on the evaluation of Ki-67, against the surgery followed by adjuvant chemotherapy (AC) and radiation therapy (RT) standard-of-care as two competing approaches to breast cancer management. Our objective is to determine whether tailoring chemotherapy treatment based on response to neoadjuvant endocrine therapy is a cost-effective approach. The NET schema is based on the ACOSOG Z1031B trial, in which post-menopausal women with estrogen receptor-positive, HER-2 negative disease would receive 4 weeks of NET followed by a core-needle biopsy for Ki-67 evaluation. If Ki-67 were lower than 10%, patients would continue in NET for 16-18 weeks followed by surgery and RT according to international guidelines. The indication of AC in these patients would be based on the preoperative endocrine prognostic index (PEPI). Patients with a PEPI score equal to zero would be spared from AC. If Ki-67&gt;10%, patients would be triaged to NAC or surgery. The cost-effectiveness analysis was conducted using a Markov model from the provider's perspective, in this case the Brazilian Health ministry. Healthcare costs, in the form of charges from the hospitals to the health ministry, were obtained from cost tables available at the federal government's webpage. In the Markov model, possible health states were disease-free, local relapse, metastatic disease and death.Transition probabilities and mortality rates were extracted from randomized studies. Our assumptions were that both treatment strategies have similar clinical outcomes and that Ki-67 is a reliable method to triage patients to NAC or surgery. We performed one-way sensitivity analysis to assess the impact of the failure of the Ki-67 test on cost-effectiveness.

Results: Our model shows that the NET schema dominates the standard-of-care strategy. Costs were R$ 47799.89 per patient for the NET strategy and R$79809.24 for the standard-of-care strategy. There was an incremental cost saving of R$32009.36 per patient for the NET strategy compared to the standard-of-care strategy. Cost-effectiveness of the NET strategy was R$2612.63 and R$4369.11 for the standard-of-care. Considering the willingness-to-pay of R$ 85494.00, defined by the World Health Organization as three times the gross domestic product per capita, the standard-of-care strategy would only be more cost-effective in the scenario of a Ki-67 test that misclassifies patients more than 9.1% of the time.

Conclusion: The use of response to neoadjuvant endocrine treatment based on Ki-67 analysis as a way to tailor locally advanced breast cancer treatment is a cost-saving strategy in the presence of robust biomarkers.

Citation Format: Goncalves R, Reinert T, Ellis MJ, Sarian LO, Filassi JR. Cost-effectiveness analysis of locally advanced estrogen receptor-positive, HER-2 negative breast cancer care using a tailored treatment approach in Brazil [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P4-12-04.

Trends in progression-free survival (PFS) and time to progression (TTP) over time within first-line aromatase inhibitors trials in hormone receptor-positive advanced breast cancer

BACKGROUND

Over the last 20 years, aromatase inhibitors (AI) have been tested in clinical trials as first-line therapy for hormone receptor-positive (HR-positive) advanced breast cancer (ABC), firstly as experimental arms, when they proved to be effective, and recently as control arms. This analysis aims to evaluate trends in progression-free survival (PFS) and time to progression (TTP) over time.

PATIENTS AND METHODS

A literature review was conducted using the MEDLINE database to identify randomized controlled phase II or III trials which reported PFS or TTP of at least one arm using first-line AI HR-positive ABC patients. A linear correlation was used to access the association between the year of the first patient enrolled and the observed PFS/TTP.

RESULTS

The search retrieved 19 trials, accounting for 4552 postmenopausal patients divided into 21 separate AI treatment arms. The PFS/TTP increased from 6 to 9 months in the earlier trials to 13-16 months in the current era, representing an absolute gain of approximately 7 months, without the addition of any other drug. Our analysis showed a positive correlation between the year of the first patient enrolled in these trials and median PFS/TTP reported (R ² = 0.34; p < 0.01). No correlation was found between the year of the first patient included in these trials and other potential prognostic factors such as visceral metastasis at baseline (R ² = 0.26; p = 0.20) or exposure to adjuvant therapy (R ² = 0.05; p = 0.18).

CONCLUSION

Patients treated with first-line AIs in the more recently conducted trials have longer PFS/TTP when compared to their counterparts treated with the same drugs in older studies. These findings have important implications for the estimation of sample size and follow-up periods for the planning of future trials as well as in the translation of the results into clinical practice decisions.

Analysis of molecular intra-patient variation and delineation of a prognostic 12-gene signature in non-muscle invasive bladder cancer; technology transfer from microarrays to PCR

Background:

Multiple clinical risk factors and genetic profiles have been demonstrated to predict progression of non-muscle invasive bladder cancer; however, no easily clinical applicable gene signature has been developed to predict disease progression independent of disease stage and grade.

Methods:

We measured the intra-patient variation of an 88-gene progression signature using 39 metachronous tumours from 17 patients. For delineation of the optimal quantitative reverse transcriptase PCR panel of markers, we used 115 tumour samples from patients in Denmark, Sweden, UK and Spain.

Results:

Analysis of intra-patient variation of the molecular markers showed 71% similar classification results. A final panel of 12 genes was selected, showing significant correlation with outcome. In multivariate Cox regression analysis, we found that the 12-gene signature was an independent prognostic factor (hazard ratio=7.4 (95% confidence interval: 3.4–15.9), P<0.001) when adjusting for stage, grade and treatment. Independent validation of the 12-gene panel and the determined cut-off values is needed and ongoing.

Conclusion:

Intra-patient marker variation in metachronous tumours is present. Therefore, to increase test sensitivity, it may be necessary to test several metachronous tumours from a patient’s disease course. A PCR-based 12-gene signature significantly predicts disease progression in patients with non-muscle invasive bladder cancer.

Expression of MAGE-A3, NY-ESO-1, LAGE-1 and PRAME in urothelial carcinoma

BACKGROUND

The potential for cancer-testis (CT) antigens as targets for immunotherapy in cancer patients has been heavily investigated, and currently cancer vaccine trials based on the CT antigens, MAGE-A3 and NY-ESO-1, are being carried out.

METHODS

We used specific q-RT-PCR assays to analyse the expression of the CT genes MAGE-A3, NY-ESO-1 (CTAG1B), LAGE-1 (CTAG2) and PRAME in a panel of bladder tumours from 350 patients with long-term follow-up and detailed treatment information.

RESULTS

Overall, 43% of the tumours expressed MAGE-A3, 35% expressed NY-ESO-1, 27% expressed LAGE-1 and 20% expressed PRAME. In all, 56% of the tumours expressed at least one of the CT genes analysed. Univariate Cox regression analysis of CT gene expression in non-muscle-invasive tumours showed that expression of MAGE-A3 (P=0.026), LAGE-1 (P=0.001) and NY-ESO-1 (P=0.040) was significantly associated with a shorter progression-free survival. In addition, we found that patients with tumours expressing PRAME responded poorly to chemotherapy (P=0.02, χ(2)-test).

CONCLUSION

Cancer-testis genes are frequently expressed in bladder cancer and especially in tumours of high stage and grade. In addition, the CT gene expression may have both prognostic and predictive value. Development of specific immunotherapy against the CT antigens in bladder cancer may ultimately increase patient survival.

New Routes to Silicic Acid Containing Inorganic-Organic Hybrid Precursors and Polymers

In view of the outstanding role that silicic acids (sa.) play in inorganic materials a survey will be presented regarding the possibilities of the integration of sa. in organic matrices via chemical reactions. The objective is to combine the advantageous properties of the silicic acid with those of the organic compounds in order to generate novel materials. The reactions of silicic acids with organic molecules, as studied by 29Si NMR spectroscopy, are described using the silicic acid H8Si8O20 with a defined double four-ring structure as an example. By silylation of the hydrophilic H8Si8O20 its functional organophilic derivatives were synthesized. The s.a. derivatives with epoxy-, alkoxy-, HSi-, ketoester or unsaturated groups are capable of condensation, polymerization, complexation or additive reactions leading to reactive inorganic-organic precursors or polymers with the defined silicic acid unit. The synthesis and structure of the following s.a. containing precursors and polymers will be reported, (a) inorganic-organic polymers with a high content of silanol groups, (b) microporous polymers free of silanol groups and (c) metal (Al, Zr) alkoxide complexes attached to defined silicic acid units. The model reactions of the double four-ring silicic acid derivatives can be transferred to technical silicic acid solutions prepared from water glass. The presented reaction pathways are a basis for the preparation of a great variety of new inorganic-organic compounds with tailor-made structures and properties which can be used for highly homogeneous and stoichiometric materials.

Cell analysis with the new Leipzig high-energy ion nanoprobe

The high-energy ion nanoprobe LIPSION at the University of Leipzig has been in operation since 1998. The ultrastable, 3.5 MV SINLETRON accelerator supplies the H+ or He+ ion beam. A magnetic scanning system moves the focused beam across the sample. At present, a resolution of 41 +/- 4 nm in the low current mode and 300 nm at 5 pA can be achieved. The experimental chamber is equipped with electron-, energy dispersive X-ray-, and particle detectors. They can be used simultaneously to analyse the sample by means of PIXE (particle induced X-ray emission), RBS (Rutherford backscattering), and in the case of thin sections or monolayer samples STIM (scanning transmission ion microscopy). A goniometer allows the application of channeling measurements in single crystals in combination with these methods. In contrast to previous publication describing microbeam facility at LIPSION, the current biomedical research has concentrated on microscopy and tomography on chondrocytes in pig cartilages and fixed single endothelial cells (HUVEC). For the irradiation of single living cells, an external beam facility with irradiation platform, fast beamgate and mini-Petri dishes is under construction.

[Need for a substance abuse medicine qualified acute inpatient treatment program in alcohol dependence]

Based on the fact that alcoholism is a mainly psychiatric/psychotherapeutic problem, qualified treatment regimens for the detoxification of addicts have been established at different places. However, a standard treatment hasn't emerged yet, neither for clinical application nor as a basis for discussion between health insurances and clinics. The following article describes essential quality criteria of a qualified acute treatment regimen for addicts. We use existing models and our own experiences of two clinics for the treatment of substances abuse with between 1300 and 1500 admissions each per year.