Early detection of pancreatic cancer using 5-hydroxymethylation profiles in plasma-derived cell-free DNA

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Background: Pancreatic cancer is one of the deadliest cancers, with approximately 15-20% of patients who present at diagnosis with a resectable disease. The major barrier to better outcomes is the lack of early-detection molecular tools to enable timely intervention. We have developed a test that enables the detection of pancreatic cancer from a simple blood draw. The test incorporates a novel, genome-wide sequencing-based epigenomics detection method that enriches for DNA loci that undergo active de-methylation. The measurement of 5-hydroxymethylcytosine (5hmC) provides a unique and stable biomarker for the early detection of cancer including pancreatic cancer. Methods: Whole-blood was obtained from a training cohort of 660 individuals (consisting of 132 pancreatic cancers (PaCa) and 528 non-cancers) and a validation cohort of 2,150 individuals (consisting of 102 PaCa and 2,048 non-cancers). Cell-free DNA (cfDNA) was isolated from plasma from which 5hmC and whole-genome libraries were generated and sequenced. Logistic regression algorithms were employed using 5hmC feature sets combined with physical characteristics of DNA fragments to optimally partition cancer from non-cancer samples. Results: Cross validation of the training model yielded an overall sensitivity of 65.9%,(95% CI, 57.2%–73.9%), early-stage (stage I-II) sensitivity of 57.1% (95% CI, 44%–69.5%) and a specificity of 98%. The model was further validated in a separate, non-overlapping set of blinded and independently processed samples and yielded an early-stage sensitivity of 68.3% (95% CI, 51.9%–81.9%) and a specificity of 96.9% (95% CI, 96.0%–97.6%). Conclusions: Our results demonstrate that plasma-derived cfDNA 5hmC profiles enable the accurate detection of early-stage PaCa, providing a valuable non-invasive tool especially for those individuals at high risk for the disease, including individuals with genetic predisposition and newly diagnosed type 2 diabetes. A larger clinical study (NODMED - NCT05188586) is ongoing and will provide clinical validation for the detection in individuals at high risk for this deadly disease.

Pancreatic cancer detection using 5-hydroxymethylation signatures in plasma-derived cell free DNA in high-risk patients with new onset diabetes

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Background: Pancreatic cancer (PaCa) is the third leading cause of cancer death in the United States despite a low incidence rate. It is often diagnosed when cancer has already metastasized to distant organs. Late diagnosis deprives patients of potentially curative treatments such as surgery and impacts survival rates. People with new onset diabetes (NOD) are at 6-8 fold increased risk for PaCa compared to the general population. Indeed, 0.85% of patients with NOD will be diagnosed with PaCa within 3 years. This population of PaCa patients with NOD constitute 25% of all new pancreatic cancer diagnoses. Surveillance of the NOD population for PaCa presents an opportunity to shift PaCa diagnosis to earlier stage. Methods: Whole blood was obtained from a cohort of 167 PaCa patients and 490 patients with cancers other than PaCa as well as 836 non-cancer controls with and without NOD. Plasma was processed to isolate cfDNA and 5hmC libraries were generated and sequenced. 5hmC data is used to generate models for PaCa detection using Bluestar Genomics’s technology platform. Results: To investigate whether PaCa can be detected in plasma, we interrogated plasma-derived cfDNA hydroxymethylation in PaCa patients and non-cancer controls. Models trained using 5hmC-based biomarkers from cfDNA consistently performed with a mean test sensitivity of 61.1% [95% confidence interval (CI): 35.7% to 82.7%] and a test specificity of 97.6% (CI: 93% to 99.5%) measured across 50 cross validation iterations within the training data set, which was composed of 48.3% early stage (Stages I & II) disease. The final model was trained using all of the training data, yielding 58.4% (CI: 47.5% to 68.8%) sensitivity at 98% (CI: 96.5% to 99.0%) specificity. This model was then tested on an independent test set with 22 PaCa patients (51.7% early stage, 15 of which was NOD) and 123 non-cancer control patients (53 of which were NOD) and yielded a classification performance of 59.1% (CI: 36.4% to 79.3%) sensitivity at 95.9% (CI: 90.8% to 98.7%) specificity. The model performance in the subset of patient cohort with NOD was 53.3% (CI: 26.6% to 78.7%) sensitivity at 94.3% (CI: 84.3% to 98.8%) specificity. Lastly, sensitivity observed on an independent validation set, composed of 56 PaCa and 117 ITTP samples, was 46.4% (CI: 33.0% to 60.2%) with 100% (CI: 96.8 to 100%) specificity. Conclusions: Our results demonstrate PaCa detection in plasma-derived cfDNA using 5hmC profiles. Overall, the model performed consistently between the training and independent validation datasets. A larger clinical study is under development to clinically validate the model described in this study with the goal of identifying occult PaCa within the NOD population in order to enable earlier detection and thus improve patient outcomes.

Pancreatic cancer detection using EpiDetect signatures in plasma-derived cell free DNA in high-risk patients with new onset diabetes

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Background: Pancreatic cancer (PaCa) is the third leading cause of cancer death in the United States despite its low incidence rate, owing to a 5-year survival rate of 10%. It is often asymptomatic in early stage, resulting in the majority of diagnoses occurring when cancer has already metastasized to distant organs. Late diagnosis deprives patients of potentially curative treatments such as surgery and impacts survival rates. Diabetes can be an early symptom of PaCa. Indeed, 25% of PaCa patients had a preceding diabetes diagnosis. Among all people with new onset diabetes (NOD), 0.85% will be diagnosed with PaCa within 3 years, which represents 6-8 fold increased risk for PaCa compared to the general population. Surveillance of the NOD population for PaCa presents an opportunity to shift PaCa diagnosis to earlier stage by finding it sooner. Methods: Whole blood was obtained from a cohort of 117 PaCa patients as well as 800 non-cancer controls with and without NOD. Plasma was processed to isolate cfDNA and 5hmC and low pass whole genome libraries were generated and sequenced. The EpiDetect assay combines 5hmC and whole genome sequencing data and were generated using Bluestar Genomics’s technology platform. Results: To investigate whether PaCa can be detected in plasma, we interrogated plasma-derived cfDNA epigenomic and genomic signal from PaCa patients and non-cancer controls. We first trained stacked ensemble models on PaCa and non-cancer samples utilizing 5hmC, fragmentation and CNV-based biomarkers from cfDNA. These models performed stably with a median of 72.8% sensitivity and 90.1% specificity measured across 25 outer fold iterations using the training data set, which was composed of 50% early stage (Stages I & II) disease. The final binomial ensemble model was trained using all of the training data, yielding an area under the receiver operating characteristic curve (auROC) of 0.9, with 75% sensitivity and 89% specificity. This model was then tested on an independent validation data set from 33 PaCa patients (24 with diabetes, 15 of which was NOD) and 202 non-cancer control patients (76 with diabetes, 51 of which was NOD) and yielded a classification performance auROC of 0.9 with 67% sensitivity at 92% specificity. Lastly, model performance in the subset of patient cohort with NOD only had an auROC of 0.87 with 60% sensitivity at 88% specificity. Conclusions: Our results indicate that 5hmC profiles along with CNV and fragmentation patterns from cfDNA can be used to detect PaCa in plasma-derived cfDNA. Overall, model performance was stable and consistent between the training and independent validation datasets. A larger clinical study is under development to investigate the utility of the model described in this pilot study in identifying occult PaCa within the NOD population, with the aim of shifting diagnosis to early stage and potentially improving patient outcomes.

Genome-wide 5hmC profiles to enable cancer detection and tissue of origin classification in breast, colorectal, lung, ovarian, and pancreatic cancers

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Background: Epigenomics assays have recently become popular tools for identification of molecular biomarkers, both in tissue and in plasma. In particular 5-hydroxymethyl-cytosine (5hmC) method, has been shown to enable the epigenomic regulation of gene expression and subsequent gene activity, with different patterns, across several tumor and normal tissues types. In this study we show that 5hmC profiles enable discrete classification of tumor and normal tissue for breast, colorectal, lung ovary and pancreas. Such classification was also recapitulated in cfDNA from patient with breast, colorectal, lung, ovarian and pancreatic cancers. Methods: DNA was isolated from 176 fresh frozen tissues from breast, colorectal, lung, ovary and pancreas (44 per tumor per tissue type and up to 11 tumor tissues for each stage (I-IV)) and up to 10 normal tissues per tissue type. cfDNA was isolated from plasma from 783 non-cancer individuals and 569 cancer patients. Plasma-isolated cfDNA and tumor genomic DNA, were enriched for the 5hmC fraction using chemical labelling, sequenced, and aligned to a reference genome to construct features sets of 5hmC patterns. Results: 5hmC multinomial logistic regression analysis was employed across tumor and normal tissues and identified a set of specific and discrete tumor and normal tissue gene-based features. This indicates that we can classify samples regardless of source, with a high degree of accuracy, based on tissue of origin and also distinguish between normal and tumor status.Next, we employed a stacked ensemble machine learning algorithm combining multiple logistic regression models across diverse feature sets to the cfDNA dataset composed of 783 non cancers and 569 cancers comprising 67 breast, 118 colorectal, 210 Lung, 71 ovarian and 100 pancreatic cancers. We identified a genomic signature that enable the classification of non-cancer versus cancers with an outer fold cross validation sensitivity of 49% (CI 45%-53%) at 99% specificity. Further, individual cancer outer fold cross validation sensitivity at 99% specificity, was measured as follows: breast 30% (CI 119% -42%); colorectal 41% (CI 32%-50%); lung 49% (CI 42%-56%); ovarian 72% (CI 60-82%); pancreatic 56% (CI 46%-66%). Conclusions: This study demonstrates that 5hmC profiles can distinguish cancer and normal tissues based on their origin. Further, 5hmC changes in cfDNA enables detection of the several cancer types: breast, colorectal, lung, ovarian and pancreatic cancers. Our technology provides a non-invasive tool for cancer detection with low risk sample collection enabling improved compliance than current screening methods. Among other utilities, we believe our technology could be applied to asymptomatic high-risk individuals thus enabling enrichment for those subjects that most need a diagnostic imaging follow up.

Abstract 783: Epigenomic detection of multiple cancers in plasma derived cell free DNA

Background: Our feasibility study employed a novel genomic detection methodology that enriches 5-hydroxymethylcytosine (5hmC) loci in cell free DNA (cfDNA) from the plasma of cancer patients using click chemistry coupled with sequencing and machine learning based classification methods. These classification methods were developed to detect the presence of disease in the plasma of cancer and control subjects. Cancer and control patient cfDNA cohorts were accrued from multiple sites consisting of 48 breast, 55 lung, 32 prostate and 2 pancreatic datasets consisting of 41 and 53 cancer subjects (Set 1 and 2). In addition, a control cohort of 260 subjects (non-cancer) was employed to match cancer patient demographics (age, sex and smoking status) in a case-control study design.

Methods: Machine learning methods, applied to each cancer case cohort individually, with a balancing non-cancer cohort, were able to classify cancer and control samples. Measures of predictive performance using 5-fold cross validation coupled with out-of-fold Area Under the Receiver Operating Characteristic Curve (AUROC) measures were employed. Gene sets selected as part of biomarker discovery were further analyzed for disease relevance using pathway analysis tools (GSEA, mSigDB).

Results: 260 controls and 229 cancers from four disease types (breast, lung, pancreas and prostate) were analyzed; more than 60% of cancer patients had early stage disease (I or II). Predictive performance, employing AUROC measures, was established for breast (0.89), lung (0.84), pancreas (set 1 - 0.95 and 2 - 0.93) and prostate (0.83). The genes defining each of these predictive models were enriched for pathways relevant to disease specific etiology, notably in the control of gene regulation in these same pathways. The breast cancer cohort consisted primarily of stage I and II patients including tumors < 2 cm and these samples exhibited a higher prediction probability score. The prostate cancer cohort consisted of both indolent and aggressive disease sample and prediction performance was equally high for both (AUROC for indolent vs aggressive was 0.81 and 0.77, respectively).

Conclusions: These findings suggest that 5hmC changes in cfDNA enable non-invasive detection of early stage breast, pancreatic, prostate, and lung cancers. Furthermore, 5hmC profiling in cfDNA may enable the prediction of clinically relevant features such as tumor size in breast adenocarcinoma or indolent disease in prostate cancer. Finally, this study identified a suite of 5hmC biomarkers that may be further validated in larger, and more diverse, patient cohorts.

Citation Format: Anna Bergamaschi, Jeremy Ku, Yuhong Ning, Francois Collin, Chris Ellison, Tierney Phillips, Erin McCarthy, Wendy Wang, Michael Antoine, David Haan, Aaron Scott, Paul Lloyd, Gulfem Guler, Alan Ashworth, Stephen Quake, Samuel Levy. Epigenomic detection of multiple cancers in plasma derived cell free DNA [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 783.

Monitoring immunotherapy response in non-small cell lung cancer patients using 5-hydroxymethylcytosine signatures in circulating cell free DNA

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Background: Liquid biopsies are gaining prominence for not only cancer diagnosis but also patient monitoring. Mutational signals derived from cell-free DNA (cfDNA) show promise to assess response to cancer treatment, including immunotherapy. However, reliance of these methods on mutational data from tissue biopsies limit their applicability when a tumor biopsy is unavailable, or when mutational landscape of tumor changes under the selective pressures of cancer drug treatment. Epigenomic approaches have the potential to address these shortcomings. Methods: Blood draws were obtained from a cohort of non-small cell lung cancer (NSCLC) patients (n = 19) who went on to anti-PD1 treatment prior to therapy start and while on therapy. cfDNA was isolated from plasma and was subsequently processed to generate 5hmC genome-wide profiles. Results: We analyzed cfDNA from NSCLC patients undergoing anti-PD1 therapy to investigate whether immunotherapy response can be detected from plasma. Using a predictive model trained on lung cancer and non-cancer samples, we were able to detect changes in prediction scores in patient treated with immunotherapy that were consistent with RECIST. Patients with progressive disease (n = 3), determined by RECIST, had prediction scores that increased while they received treatment. On the other hand, majority of the patients that exhibited partial response to treatment (n = 12) had predictive scores that decreased with treatment, again consistent with RECIST. Furthermore, score changes consistent with RECIST was observed one cycle prior to the RECIST timepoint in all except one patient, where an extra blood draw after baseline was available (n = 7). Annotation of the regions that account for differential scoring identified enhancer, 5’UTR and promoter regions. Comparison of partial responders to patients with progressive disease revealed genes involved in metastasis, oncogenes and tumor suppressors that change in opposing directions between these patient groups, consistent with the underlying biology. Conclusions: Our results suggest that 5hmC profiles from cfDNA can be used to determine immunotherapy response in non-small cell lung cancer patients. Compared with mutation based liquid biopsy methods to assess response, epigenomics-based methods have the advantage of being agnostic to starting tumor mutations, and not relying on a mutational analysis from tumor biopsy. Future work will help determine applicability of this method to other kinds of therapies and cancer types.

Effect of detection of epigenomic changes in plasma-derived cell-free DNA on multicancer classification

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Background: Epigenomic changes in DNA methylation patterns are more precisely delineated by active demethylation events as marked by 5-hydroxymethylation (5hmC) of cytosine residues. 5hmC appears to be dynamically modulated in tumor tissues and can be employed as a cancer biomarker. Strategies which interrogate 5hmC genome-wide patterns in a liquid biopsy context may provide efficient and precise technology for early cancer screening and detection. In this study we identified genome-wide 5hmC changes in plasma based circulating free DNA (cfDNA) from breast, colorectal, lung, pancreatic and prostate cancer patients versus non-cancer individuals. Methods: cfDNA was isolated from plasma, enriched for the 5hmC fraction using novel click-chemistry protocol for labelling followed by sequencing and alignment to a reference genome to construct features sets of 5hmC patterns. Regularized classification models were constructed to classify cancer samples apart from non-cancer. Results: > 500 non-cancer individuals and > 500 cancer patients across five cancer types (breast, colorectal, lung, pancreas and prostate) were included in this study. About 60% of the cancer samples were early stage disease (I or II). The ability to classify non-cancer versus cancer patients was evaluated by 5-fold cross validation of our trained prediction models. Our models were able to classify all breast cancer with a test auROC of 0.86 while prediction model classification for ER negative samples had an auROC of 0.92. Colorectal performance auROC was 0.9; lung auROC = 0.92, pancreatic auROC = 0.97 and prostate auROC = 0.91. Overall sensitivity range, when allowing 2% false positive, was between 85% and 52%. Further using 5hmC signal in blood we were able to identify several signaling pathways specifically relevant to the biology of the cancers investigated. Conclusions: These findings further demonstrate that 5hmC changes in cfDNA enable non-invasive detection of breast, colorectal, lung pancreatic, and prostate cancers. Further, 5hmC signals enabled the identification of a suite of cancer signaling pathways differentially enriched in cancers versus non-cancers. These data suggest that dynamic changes in tumor cell methylation, detectable through 5-hydroxymethylation, are contained in the circulating blood and signal active disease biology.

Changes in DNA hydroxymethylation for the detection of multiple cancers in plasma cell-free DNA

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Background: Methylation and hydroxymethylation of cytosines enable the epigenomic regulation of gene suppression and activation. 5-hydroxymethyl-cytosine (5hmC) is globally decreased in tumor tissue. However, genome-wide analysis using precise 5hmC labelling techniques reveals more nuanced changes upon tumorigenesis and raises the possibility that this loss could be exploited for developing a cancer biomarker. This suggests that 5hmC profiles might enable discrete classification of not only tumor tissue but also of tumor cell-free DNA (cfDNA). We sought to identify genome-wide 5hmC changes in plasma based cfDNA from cancer patients representing multiple disease types, stages and clinical characteristics in comparison with non-cancer patients. Methods: cfDNA was isolated from plasma, enriched for the 5hmC fraction using chemical labelling, sequenced, and aligned to the genome to determine 5hmC counts per genomic feature. Regularized regression models were constructed to classify cancer samples (age matched or corrected for smoking status) on non-overlapping training (80% of all samples) and test sample sets (20% of all samples). Results: 226 non-cancer patients and 278 cancers across four cancer types (breast, colorectal, lung-squamous and pancreas) were included in this study, where more than 60% of cancer samples were early stage disease (I or II). Upon comparison with non-cancer samples, 5hmC peaks have reduced enrichment in exons in breast, colorectal and lung cancer but not in pancreatic cancer. Further, 5hmC peaks in pancreas show different patterns of enrichment in 3’UTR, translational termination sites, promoters and LTR. Overall 5hmC signal density was reduced in late stage cancers across all four diseases. The ability to classify non-cancer versus cancer patients was evaluated via cross-validation of out of fold prediction in the training set with AUC > 0.84 for all four cancer types. Further, test set sensitivity across all four cancer types was found to be > 66% with 98% specificity. Conclusions: These findings suggest that 5hmC changes in plasma cfDNA enable classification of early stages of breast, colorectal, lung-squamous and pancreas cancer and are promising biomarkers for disease detection.

GSM-like radiofrequency exposure induces apoptosis via caspase-dependent pathway in infant rabbits

BACKGROUND

There have been several Radio Frequency (RF) field researches on various populations and groups of different ages in recent years. However, the most important group for research has been declared as the pregnant women and their babies.

OBJECTIVE

The aim of the study was to analyse the effect on apoptotic factors of RF fields on newborn rabbit liver tissues.

MATERIALS AND METHODS

Cytochrome c and AIF (Apoptosis Inducing Factor) levels were measured by western blot and caspase 1, 3 and 9 activities were measured by colorimetric method.

RESULTS

Cytochrome c and AIF levels were not altered, but all caspase activities were increased in female infant rabbits that exposed to 1800 MHz GSM-like RF signals when they reached 1 month of age and caspase 1 and caspase 3 levels were decreased in male infant rabbits that exposed to 1800 MHz GSM-like RF signals between 15th and 22nd days of the gestational period. Results showed that 1800 MHz GSM-like RF exposure might lead to apoptosis in infant rabbit's liver tissues.

CONCLUSION

According to the results, we suggest that postnatal RF exposure causes caspase dependent apoptosis in female infant rabbits liver tissues (Tab. 1, Fig. 2, Ref. 27).

Hürthle cell presence alters the distribution and outcome of categories in the Bethesda system for reporting thyroid cytopathology

OBJECTIVES

We aimed to determine whether the presence of Hürthle cells altered the distribution of categories in the Bethesda system for reporting thyroid cytopathology, or the expected neoplastic and malignant outcome.

METHODS

Fine needle aspiration (FNA) cytology reports of Hürthle cells in a 2-year period were evaluated. The distribution of Bethesda system categories and the outcome at partial or complete thyroidectomy were compared for FNAs with and without Hürthle cells.

RESULTS

Of 895 adequate FNAs with Hürthle cells, 764 (85.4%) were classified as benign, 86 (9.6%) as atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS), 32 (3.6%) as follicular neoplasm/suspicious for follicular neoplasm (FN/SFN), 12 (1.3%) as suspicious for malignancy (SFM) and one (0.1%) as malignant. Of 10 359 adequate FNAs without Hürthle cells, 9707 (93.7%) were classified as benign, 412 (4.0%) as AUS/FLUS, 77 (0.7%) as FN/SFN, 93 (0.9%) as SFM and 70 (0.7%) as malignant. The distribution of categories in FNAs with and without Hürthle cells was significantly different (P < 0.001) as a result of a decrease in benign and an increase in AUS/FLUS and FN/SFN categories. Among 128 patients with and 582 without Hürthle cells undergoing surgery, the overall neoplastic and malignancy rates were higher in the former than in the latter group (27.3% versus 14.9%, P < 0.001; 21.1% versus 11.7%, P = 0.003; respectively). Although neoplastic and malignant rates were higher in the group with than without Hürthle cells in all categories, the differences were only significant for a neoplastic outcome of benign cytology (15.1% versus 6.0%, P = 0.0013) and a malignant outcome of FN/SFN cytology (63.6% versus 21.9%, P = 0.0108).

CONCLUSIONS

We found that the rates of AUS/FLUS and FN/SFN categories in the Bethesda system were higher when Hürthle cells were present. After surgery, neoplastic and malignant outcomes were significantly higher in the Hürthle cell group.

Evaluation of changes in biologic markers ER, PR, HER 2 and Ki-67 index in breast cancer with administration of neoadjuvant dose dense doxorubicin, cyclophosphamide followed by paclitaxel chemotherapy

PURPOSE

The aim of this study was to assess the changes in biologic markers of breast cancer ER, PR, HER 2 and Ki-67 in locally advanced breast cancer patients after neoadjuvant chemotherapy.

METHODS

Data from 63 locally advanced breast cancer patients (stage II or III), whose histological diagnosis was made by core biopsies were retrospectively evaluated. The patients were given 4 cyles of 600 mg/m(2) cyclophosphamide, 60 mg/m(2) doxorubicin every 15 days followed by 4 cycles of paclitaxel 175 mg/m(2) every 15 days, and they underwent surgery within two weeks after the last chemotherapy cycle. Expressions in the preoperative and postoperative status of ER, PR, HER 2 and Ki-67 were compared.

RESULTS

The patient mean age was 49.2 ±10.7 years and most (57.1%) were premenopausal. Clinical stages of patients ranged between T2N1 and T3N2. The pathological complete response (pCR) rate was 14.9 % (N=9). Two (5.7%) patients who were ER positive prior to treatment showed ER negativity after treatment. In 7 (21.17percnt;) patients PR became negative after neoadjuvant chemotherapy and in 3 (9.0%) patients PR became positive. Changes in ER and PR receptors were not statistically significant (ER p=0.500 and PR p=0.549, respectively), whereas in 2 (5. 8%) patients hormonal status changed significantly when compared to initial biopsies (p=0.003). In addition, median value for PR intensity decreased from 20 to 10% (p=0.003) and Ki-67 values decreased from 10 to 1% (p<0.001) following neoadjuvant therapy. Six (17%) patients exhibited some changes in HER 2 staining. HER 2 expression became 2+ in 3 patients who were HER 2 negative prior to treatment, and HER 2 expression became negative in two patients with HER 2 1+ and 2+ prior to treatment following neoadjuvant chemotherapy.

CONCLUSION

The biological markers ER, PR, HER 2 and Ki- 67 index demonstrated differences after neoadjuvant treatment in breast cancer patients. These changes may affect the treatment decision.

Evaluation of changes of biologic markers ER, PR, HER 2 and Ki-67 in breast cancer with administration of neoadjuvant dose-dense doxorubicin, cyclophosphamide followed by paclitaxel

PURPOSE

To assess the changes of biologic markers estrogen receptors (ER), progesterone receptors (PR), HER 2 and Ki-67 in locally advanced breast cancer patients after neoadjuvant chemotherapy.

METHODS

Data from 63 locally advanced breast cancer patients (stage II or III), whose histological diagnosis was made by core biopsies were retrospectively evaluated. The patients were given 4 cycles of 600 mg/m(2) cyclophosphamide, 60 mg/m(2) doxorubicin every 15 days, followed by 4 cycles of paclitaxel 175 mg/m(2), followed by mastectomy within 2 weeks after the last chemotherapy cycle. The changes in ER, PR, HER 2 and Ki-67 status of the operated tumor tissue were compared with the material obtained by initial core biopsies.

RESULTS

The patient mean age was 49.2±10.7 years. Most (57.1%) were premenopausal. Clinical disease stages ranged between T2N1 and T3N2. Pathological complete response (pCR) rate was 14.9 7 percent; (n=9). Two (5.7%) patients who were ER positive prior to treatment showed ER negativity after treatment. In 7 (21.1%) patients PR became negative and in 3 (9.0%) became positive after neoadjuvant chemotherapy. Changes in ER and PR receptors were not statistically significant (p=0.500 and PR p=0.549, respectively), whereas in 2 (5.8%) patients hormonal status changed significantly when compared to initial biopsies (p=0.003). In addition, the median value of PR intensity decreased from 20 to 10% (p=0.003) and Ki-67 decreased from 10 to 1% (p<0.001) following neoadjuvant therapy. Five (14.1%) patients exhibited some changes in HER 2 expression: HER 2 expression became 2+ in 3 patients previously being HER 2 negative, and in 2 patients HER 2 became negative whilst it was 1+ and 2+ prior to neoadjuvant chemotherapy.

CONCLUSION

It was observed that the biologic markers ER, PR, HER 2 and Ki-67, from the same tumor material demonstrated differences after neoadjuvant treatment in breast cancer patients. These changes may affect the treatment decision.

ERCC1 expression in triple negative breast cancer

PURPOSE

Excision repair cross-complementation group 1 (ERCC1), which is a component of nucleotide excision repair (NER) pathway, removes platinum-induced DNA adducts. Overexpression of ERCC1 has been associated with resistance to platinum-based chemotherapy in ovarian and lung cancers. Detecting ERCC1 overexpression is important in considering treatment options for triple negative breast cancer (TNBC), and in conducting and interpreting trials that search to find specific chemotherapy regimens for TNBC. In this study we aimed to study ERCC1 overexpression in patients with TNBC.

METHODS

A monoclonal antibody against ERCC1 was used for immunohistochemical (IHC) analysis of tumor samples. Tumor samples from 45 patients were evaluated by two experienced pathologists who were blinded to clinical data. A semi-quantitative H score (intensity staining scale ranging from no staining/0 to very intense staining/3+) was calculated by multiplying staining intensity with extent score. Tumors with H score ≥ 1 were classified as ERCC1-positive.

RESULTS

ERCC1 expression was positive in 73.3% of the tumor samples with an H score ≥ 1 and 26.7% of the tumor samples stained negative with an H score lt; 1. Of the tumor samples 15.5% stained diffusely and intensively.

CONCLUSION

Our study demonstrated that about two thirds of the TNBC showed positive expression of ERCC1, which may be predictive of a poor response to platinum-based chemotherapy.

The effects of L-NG-nitroarginine in a zymosan-induced multiple organ dysfunction syndrome model

BACKGROUND

The aim of this study was to investigate the role of nitric oxide in mesenteric ischemia, organ injury and survival in zymosan-induced multiple organ dysfunction syndrome (MODS) by using the nonselective nitric oxide synthase inhibitor L-N(G)-nitroarginine (L-NNA).

METHODS

Swiss albino mice (20-40 g) were used in the study. The animals were randomly divided into four groups. The first group was treated intraperitoneally with saline and served as the sham group for L-NNA. The second group was treated with zymosan (500 mg/kg). The mice in the third and fourth group received L-NNA (20 mg/kg), 1 and 6 h after saline or zymosan administration. Six hours after the administration of zymosan, animals were used for mesenteric arterial blood flow (MABF) measurements and then sacrificed for biochemical and histopathological analyses at the 18th hour.

RESULTS

In zymosan-treated animals, MABF was significantly lower than that of solvent saline-treated controls (controls: 4.7 +/- 0.8 ml.min(-1); zymosan: 1.7 +/- 0.7 ml.min(-1), p < 0.05). L-NNA did not prevent zymosan-induced MABF decrease (controls: 4.5 +/- 0.8 ml.min(-1); zymosan: 2.5 +/- 1.4 ml.min(-1), p <0.05). Also treatment with L-NNA has no beneficial effect on survival and organ injury in zymosan-induced MODS.

CONCLUSION

In this study, inhibition of both inducible and constitutive nitric oxide synthase by L-NNA did not abolish the harmful effects of zymosan. L-NNA remains an agent without any therapeutic potential in this acute experimental model of MODS.

Comparison of ER, PR, HER2 in primary and paired relapsed/metastatic lesions of metastatic breast cancer patients

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Background: The assessment of ER, PR and HER2 is made routinely in every breast cancer patient to have information about prognosis and to select patients (pts) who are candidates for hormonal and anti-HER2 therapy. Recent studies have shown some degrees of discordance in ER, PR, and HER-2 expression between primary and recurrent/metastatic lesions (RML). In this study we compared the ER, PR, and HER2 status of the primary and paired RML in metastatic breast cancer pts. Methods: Analysis was made on 79 metastatic breast cancer pts whose ER, PR, and/or HER2 status were known both on the tissue samples of primary and RML. ER, PR, and HER2 status were determined by immunohistochemistry and/or fluorescence-in-situ hybridization. Results: Among the RML sites, 24% were locoregional, 76% were distant metastatic sites. Among 72 pts with known ER expression on both primary and RML, 36% showed discordance on ER expression. Most of the change occurred from negative to positive ER status (15 of 48 ER positive primaries had ER negative paired metastasis and 11 of 24 ER negative primaries had ER positive paired metastasis). Among 68 pts with known PR expression on both primary and RML, 51.5% showed discordance on PR expression. Change in PR status from positive to negative and negative to positive was similar (23 of 45 PR positive primaries had PR negative paired metastasis and 12 of 23 PR negative primaries had PR positive paired metastasis). Among 58 pts with known HER2 expression on both primary and RML, 15.5% showed discordance on HER2 expression. Six pts with HER-2 negative primaries, showed HER2 overexpression in their paired RML. Four pts who had HER2 overexpressing primary did not show HER2 expression in the paired RML. Conclusions: A proportion of pts show discordances in hormonal receptor and HER2 expression between the primary tumor and the paired RML. As these discordant results make changes in treatment decision, a biopsy of the metastatic lesion could be recommended in metastatic breast cancer pts when feasible.

No significant financial relationships to disclose.

Single-dose dexmedetomidine attenuates airway and circulatory reflexes during extubation

BACKGROUND

The alpha agonist dexmedetomidine, a sedative and analgesic, reduces heart rate and blood pressure dose-dependently. We investigated whether it also has the ability to attenuate airway and circulatory reflexes during emergence from anaesthesia.

METHODS

Sixty ASA I-III patients received a standard anaesthetic. Five minutes before the end of surgery, they were randomly allocated to receive either dexmedetomidine 0.5 microg/kg (Group D) (n=30) or saline placebo (Group P) (n=30) intravenously (i.v.) over 60 s in a double-blind design. The blinded anaesthetist awoke all the patients, and the number of coughs per patient was continuously monitored for 15 min after extubation; coughing was evaluated on a 4-point scale. Any laryngospasm, bronchospasm or desaturation was recorded. Heart rate (HR) and systolic and diastolic blood pressure (SAP, DAP) were measured before, during and after tracheal extubation. The time from tracheal extubation and emergence from anaesthesia were recorded.

RESULTS

Median coughing scores were 1 (1-3) in Group D and 2 (1-4) in Group P (P<0.05), but there were no differences between the groups in the incidence of breath holding or desaturation. HR, SAP and DAP increased at extubation in both groups (P<0.05), but the increase was less significant with dexmedetomidine. The time from tracheal extubation and emergence from anaesthesia were similar in both groups.

CONCLUSION

These findings suggest that a single-dose bolus injection of dexmedetomidine before tracheal extubation attenuates airway-circulatory reflexes during extubation.

Propofol and propofol-ketamine in pediatric patients undergoing cardiac catheterization

We investigated the effects of propofol and propofol-ketamine on hemodynamics, sedation level, and recovery period in pediatric patients undergoing cardiac catheterization. We performed a prospective, randomized, double-blind study. The study included 60 American Society of Anesthesiologists physical status II or III (age range, 1 month-13 years) undergoing cardiac catheterization for evaluation of congenital heart disease. Propofol and ketamine were prepared in 5% glucose solution to a final concentration of 5 and 1 mg/ml, respectively; similar injectors containing 5% glucose solution only were prepared. Fentanyl (1 microg/kg) and propofol (1.5 mg/kg) were given to both groups. Then, group 1 received 0.5 ml/kg of 5% glucose and group 2 0.5 ml/kg of ketamine solution by an anesthesiologist who was unaware of the groups of patients. Local anesthesia with 1% lidocaine was administered before intervention in all patients. The noninvasively measured mean arterial pressure, heart rate, respiratory rate, and peripheral oxygen saturation were recorded at the baseline, following drug administration, at 3, 5, 10, 15, 20, and 30 minutes and then at 15-minute intervals until the end of the procedure. Additional drug and fentanyl requirements to maintain a sedation level of 4 or 5 were recorded. After the procedure, the time to a Steward recovery score of 6 and adverse effects in the first 24 hours were recorded. The number of patients with more than a 20% decrease in mean arterial pressure was 11 in group 1 and 3 in group 2 (p < 0.05). The number of patients who experienced more than a 20% decrease in heart rate was 12 in group 1 and 5 in group 2 (p = 0.054). Ten patients in group 1 and 3 patients in group 2 required additional fentanyl doses (p = 0.057). The number of additional propofol doses was lower in group 2 (p < 0.05). Propofol combined with low-dose ketamine preserves mean arterial pressure better without affecting the recovery and thus is a good option in pediatric patients undergoing cardiac catheterization.