Hadar Goldvaser

Tumor cells derived exosomes contain hTERT mRNA and transform nonmalignant fibroblasts into telomerase positive cells

Exosomes are small (30-100nm) vesicles secreted from all cell types serving as inter-cell communicators and affecting biological processes in “recipient” cells upon their uptake. The current study demonstrates for the first time that hTERT mRNA, the transcript of the enzyme telomerase, is shuttled from cancer cells via exosomes into telomerase negative fibroblasts, where it is translated into a fully active enzyme and transforms these cells into telomerase positive, thus creating a novel type of cells; non malignant cells with telomerase activity. All tested telomerase positive cells, including cancer cells and non malignant cells with overexpressed telomerase secreted exosomal hTERT mRNA in accordance with the endogenous levels of their hTERT mRNA and telomerase activity. Similarly exosomes isolated from sera of patients with pancreatic and lung cancer contained hTERT mRNA as well. Telomerase activity induced phenotypic changes in the recipient fibroblasts including increased proliferation, extension of life span and postponement of senescence. In addition, telomerase activity protected the fibroblasts from DNA damage induced by phleomycin and from apoptosis, indicating that also telomerase “extracurricular” activities are manifested in the recipient cells. The shuttle of telomerase from cancer cells into fibroblasts and the induction of these changes may contribute to the alterations of cancer microenvironment and its role in cancer. The described process has an obvious therapeutic potential which will be explored in further studies.

Adjuvant Docetaxel and Cyclophosphamide (DC) with Prophylactic Granulocyte Colony-Stimulating Factor (G-CSF) on Days 8 &12 in Breast Cancer Patients: A Retrospective Analysis

Purpose Four cycles of docetaxel/cyclophosphamide (DC) resulted in superior survival than doxorubicin/cyclophosphamide in the treatment of early breast cancer. The original study reported a 5% incidence of febrile neutropenia (FN) recommending prophylactic antibiotics with no granulocyte colony-stimulating factor (G-CSF) support. The worldwide adoption of this protocol yielded several reports on substantially higher rates of FN events. We explored the use of growth factor (GF) support on days 8 and 12 of the cycle with the original DC protocol. Methods Our study included all consecutive patients with stages I–II breast cancer who were treated with the DC protocol at the Institute of Oncology, Davidoff Center (Rabin Medical Center, Petah Tikva, Israel) from April, 2007 to March, 2012. Patient, tumor characteristics, and toxicity were reported. Results: In total, 123 patients received the DC regimen. Median age was 60 years, (range, 25–81 years). Thirty-three patients (26.8%) were aged 65 years and older. Most of the women (87%) adhered to the planned G-CSF protocol (days 8 &12). 96% of the patients completed the 4 planned cycles of chemotherapy. Six patients (5%) had dose reductions, 6 (5%) had treatment delays due to non-medical reasons. Thirteen patients (10.6%) experienced at least one event of FN (3 patients had 2 events), all requiring hospitalization. Eight patients (6.5%) required additional support with G-CSF after the first chemotherapy cycle, 7 because of FN and one due to neutropenia and diarrhea. In Conclusion Primary prophylactic G-CSF support on days 8 and 12 of the cycle provides a tolerable option to deliver the DC protocol. Our results are in line with other retrospective protocols using longer schedules of GF support.

Screening for occult cancer in idiopathic venous thromboembolism — Systemic review and meta-analysis

BACKGROUND Idiopathic venous thromboembolism (VTE) may be associated with an occult malignancy. Early detection of cancer might be translated to a better prognosis for these patients. However, the efficacy of extensive screening for cancer in patients with idiopathic VTE is controversial. MATERIALS AND METHODS Systemic review and meta-analysis of all available prospective trials comparing extensive to limited screening for occult malignancies in patients with idiopathic VTE. PRIMARY OUTCOME all-cause mortality. SECONDARY OUTCOMES cancer related mortality, early cancer diagnosis, cancer diagnosis at the end of follow up and cancer diagnosis at an early stage. Risk ratios (RR) with 95% confidence intervals (CIs) were estimated and pooled. RESULTS The study included five trials and 2287 patients. Extensive screening did not affect all-cause mortality at the end of follow up [RR 0.86 (95% CI 0.58-1.27)] or cancer-related mortality [RR 0.93 (95% CI 0.54-1.58)]. Yet, it yielded more diagnoses of cancer [RR 2.17 (95% CI 1.42-3.32)]. Rates of cancer diagnosis at an early stage did not differ statistically between the two groups [RR 1.49 (95% CI 0.86-2.56)]. However, analysis of the randomized controlled trials alone showed a tendency towards early stage cancer at diagnosis in extensive screening group in, with results almost statistically significant [RR 2.14 (95% CI 0.98-4.67), p=0.06]. CONCLUSIONS Extensive screening for malignancy after idiopathic VTE does not affect mortality rates. Yet, it yields more cancer diagnoses shortly after the VTE event. Further research is needed to determine whether extensive screening might be proper for specific high risk populations.

High Lung Cancer Incidence in Heavy Smokers Following Hospitalization due to Pneumonia

INTRODUCTION The rate of lung cancer incidence following pneumonia in heavy smokers is unknown. Heavy smokers hospitalized due to community-acquired pneumonia might be at high risk for subsequent lung cancer. The primary objective of this study was to determine lung cancer incidence in this high-risk population. PATIENTS AND METHODS This was a single-center, retrospective cohort study that included heavy smokers hospitalized due to community-acquired pneumonia between January 1, 2007 and December 31, 2011 in Beilinson hospital, a large community hospital and tertiary center. Patients were identified by International Classification of Diseases, Ninth Revision coding from the hospitals registry. Two physicians reviewed every patients medical file for patient demographics, smoking history, lung cancer risk factors, and anatomical location of pneumonia. Data were cross-checked with the database at the national cancer registry for new diagnoses of cancer. RESULTS There were 381 admissions for community-acquired pneumonia included in the final analysis. Thirty-one cases (8.14%; 95% confidence interval [CI], 5.9%-11.2%) of lung cancer were diagnosed during the first year after hospitalization. Lung cancer incidence was significantly higher in patients who had upper-lobe pneumonia (23.8%; 95% CI, 14.9%-40%). Lung cancer was located within the lobe involved by the pneumonia in 75.8% of patients. CONCLUSIONS A high lung cancer rate was found in heavy smokers admitted due to community-acquired pneumonia. The association was especially strong for patients with upper-lobe pneumonia. Screening with chest computed tomography should be strongly considered for these patients.

Perception of prognosis of cancer patients by non-oncologists

Data are lacking regarding the perception of cancer patients’ prognosis by physicians who are not oncologists.

Malignancy associated SIADH: Characterization and clinical implications

Abstract Purpose: To determine the distribution of etiologies for the syndrome of inappropriate antidiuretic hormone secretion (SIADH) in hospitalized patients with active malignancies and to characterize them according to the different etiologies. Methods: A single center retrospective study including all patients with active malignancies diagnosed with SIADH in a large community hospital and tertiary center between 1 January 2007 and 1 January 2013. Two physicians reviewed every patient’s medical file for predetermined relevant clinical data. Results: The study cohort included 204 patients. 74.4% of those with solid tumors had metastatic disease. Most patients (149, 73%) had malignancy associated SIADH, while 55 (27%) had SIADH due to other etiologies. All of the major malignancy types were implicated in SIADH. Patients with breast cancer without lung or brain involvement were significantly less likely to be diagnosed with malignancy associated SIADH compared with other malignancies [Odds ratio (OR) 0.031, 95% CI 0.003–0.25, p < 0.001]. Patients with malignancy associated SIADH had lower serum sodium concentrations on short-term follow-up (p = 0.024) and significantly shorter median survival (58 vs. 910 days, p < 0.001). Short-term hyponatremia correction was associated with better survival. Conclusions: SIADH is associated with most malignancy types. Physicians caring for patients with breast cancer without lung or brain involvement diagnosed with SIADH without an obvious etiology should consider obtaining lung and brain imaging to rule out undiagnosed metastatic spread. Patients with malignancy associated SIADH have considerably worse outcomes compared to cancer patient with SIADH due to other etiologies. Short-term sodium concentration can be used as a prognostic marker for these patients.

Abstract P5-08-25: The association between smoking and breast cancer characteristics and outcome

Background: Smoking is associated with an increased incidence of hormone receptor positive breast cancer. Data regarding worse breast cancer outcome in smokers are accumulating. Current literature regarding the impact of smoking on breast cancer characteristics is limited. The aim of this study was to evaluate the impact of smoking on the characteristics and outcome of estrogen receptor positive, human epidermal growth factor receptor 2 (HER2) negative early breast cancer. Methods: This was a retrospective single center study. All patients diagnosed from 4/2005 through 3/2012 and treated in our institute for early, estrogen receptor positive, HER2 negative breast cancer, whose tumors were sent for Oncotype DX analysis were included. Medical records were reviewed for demographics, clinico-pathological parameters, treatment and outcome. Patients were grouped and compared according to smoking history (present or past smokers vs. never smokers) and status (current vs. former and never smokers). Heavy smokers (pack years ≥30) were analyzed separately. Results: A total of 671 patients were included. 28.7% had a history of smoking, 17% were current smokers and 11.5% were heavy smokers. Smoking had no impact on tumor size, nodal involvement and Oncotype DX recurrence score. Angiolymphatic and perineural invasion rates were higher in current smokers than in the rest of the cohort (11% vs. 5.1%, p=0.023, 9% vs. 3.45%, p=0.013, respectively). Smoking had no other impact regarding histological characteristics. Five-year disease free survival and overall survival rates were 95.7% and 98.5%, respectively. Smoking had no impact on outcome. Conclusions: In patients with estrogen receptor positive, HER2 negative, early breast cancer, smoking had no clinically significant influence on tumor characteristics and outcome. As the study was limited to a specific subgroup of the breast cancer population in this heterogeneous disease and since smoking is a modifiable risk factor for the disease, further research is required to clarify the possible impact of smoking on breast cancer. Citation Format: Goldvaser H, Gal O, Rizel S, Hendler D, Neiman V, Shochat T, Sulkes A, Brenner B, Yerushalmi R. The association between smoking and breast cancer characteristics and outcome [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 P5-08-25.

Abstract 5219: Circulating hTERT (human telomerase) mRNA: mechanism of action and potential use for early diagnosis of malignancy

Proceedings: AACR 106th Annual Meeting 2015; April 18-22, 2015; Philadelphia, PA In contrast to current impressive achievements in the biological knowledge and therapy of cancer, the field of early diagnosis lags behind and presents an unmet need. We hereby present the human telomerase as a potential tool for early diagnosis of cancer. Telomerase activation is a prerequisite for the perpetuation of the malignant clone during cancer progression as it elongates telomeres in each cell division. hTERT mRNA is shed into the serum and remains stable in vesicular forms named “Exosomes”. Exosomes are secreted by most cells containing nucleic acids, proteins and lipids. We established a method for the detection and quantification of hTERT mRNA products in exosomes derived from growth media of cancer cell lines and human sera for the future use as a diagnostic tool for the early detection of cancer. In four cancer cell lines we detected exosomal hTERT RNA expression, which also correlated with its telomerase activity and intracellular hTERT mRNA expression, compared to a non-telomerase expressing cell line. We studied the crosstalk between T cell leukemia derived exosomes and primary human fibroblast cells and revealed that primary cells can uptake exosomes derived from a different type of cell. The secreted exosomes affected the recipient cells by increasing the hTERT mRNA 6 hours post exposure and increasing telomerase levels and expression 24 hours post exposure, while the levels of the hTERT core promoter transcription factors did not change. For the future goal of establishing a method of early diagnosis of malignancies we screened 63 patients with different malignancies and compared their exosomal hTERT mRNA expression in the sera to that of 20 healthy volunteers. The results have shown that the expression of hTERT is variable among malignancies and between different patients with the same cancer type. To exclude some variables, such as drugs, that can influence exosome secretion from cells, we examined the influence of three chronically administered drugs on our chosen experimental cell lines. The drugs tested were Aspirin, Simvastatin and Captopril. While Simvastatin significantly decreased hTERT mRNA in exosomes derived from one cell line, neither aspirin nor Captopril effected the secretion of exosomes, indicated by a similar hTERT expression in the relevant treated cells. Furthermore, no change in the intracellular hTERT expression and telomerase activity after drug exposure was evident. In the light of these results we concluded that exosomes derived from tumor cells can affect the surrounding microenvironment by exploiting the recipient cell mechanism and promoting the activation of telomerase in those recipient cells. Understanding of these mechanisms may have a strong impact on deciphering metastases formation. Hopefully, promoting hTERT mRNA as a novel marker for malignancies will enable us to develop a new diagnostic tool for future use in the early diagnosis of cancer. Citation Format: Orit Uziel, Anna Gutkin, Einat Beery, Jardena Nordenberg, Hadar Goldvaser, Yair Zloof, Steven Henick, Meir Lahav. Circulating hTERT (human telomerase) mRNA: mechanism of action and potential use for early diagnosis of malignancy. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5219. doi:10.1158/1538-7445.AM2015-5219