Telomerase activity correlates with tumor aggressiveness and reflects therapy effect in breast cancer

Hoos, Axel; Hepp, H; Kaul, S.; Ahlert, T.; Bastert, G.; Wallwiener, D.

doi:10.1002/(sici)1097-0215(19980220)79:1<8::aid-ijc2>3.0.co;2-5

Cited by 108 publications

(66 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Serum levels of a tumor marker may increase as a tumor grows larger [13]. However, tumor mass did not affect the abundance of breath VOC biomarkers of lung cancer; these remained relatively constant, as shown by the similarity of ROC curves in TNM stages 1 through 4 (Fig.…”

Section: Effect Of Tumor Massmentioning

confidence: 89%

Detection of lung cancer using weighted digital analysis of breath biomarkers

Phillips

Altorki

Austin

et al. 2008

Clinica Chimica Acta

210

168

View full text Add to dashboard Cite

show abstract

Section: Effect Of Tumor Massmentioning

confidence: 89%

Detection of lung cancer using weighted digital analysis of breath biomarkers

Phillips

Altorki

Austin

et al. 2008

Clinica Chimica Acta

210

168

View full text Add to dashboard Cite

show abstract

“…Initial results suggested that smaller, lymph nodenegative tumors were more likely to be telomerasenegative than their larger, lymph node-positive counterparts (Hiyama et al, 1996;Kim et al, 1994), and it was postulated that telomerase activity is acquired during tumor progression to metastasis (Hiyama et al, 1996). More recently, some studies have found correlations between telomerase activity and stage, traditional prognostic indicators, and clinical outcome in invasive breast cancer (Clark et al, 1997;Hoos et al, 1998). Other studies, however, failed to show a correlation between telomerase activity and prognostic factors or clinical outcome in breast cancer (Bednarek et al, 1997;Carey et al, 1998;Nawaz et al, 1997;Sugino et al, 1996;Tsao et al, 1997) and (Carey et al, in preparation, 1999).…”

Section: Introductionmentioning

confidence: 99%

Telomerase activity in ductal carcinoma in situ and invasive breast cancer

et al. 1999

View full text Add to dashboard Cite

The increasing number of breast carcinoma in situ detected by screening procedures makes it imperative to develop improved markers to stratify the risk of invasive cancer. Telomerase is detectable in invasive cancer, but not in normal tissues. We have microdissected frozen tissue blocks containing both DCIS and invasive cancer to assay the telomerase activity of these two lesions. The 46 available cases of concurrent DCIS and invasive breast cancer resulted in 43 DCIS samples and 38 invasive cancer samples adequate for analysis. Seventy per cent of the DCIS and all invasive cancer samples tested had detectable telomerase activity. In addition, we analysed telomerase activity in ten cases of DCIS that were not associated with invasive cancer, and detected telomerase activity in seven (70%). Mixing experiments showed no evidence of telomerase inhibitors in telomerase negative samples. Furthermore, periductal in¯ammatory in®ltrates were shown to be a potential confounding source of telomerase activity. Since DCIS lesions appear to be heterogeneous with respect to telomerase activity, and telomerase activation appears to precede the development of invasive cancer, telomerase activity may be a useful adjunct in stratifying the risk of developing invasive breast cancer in patients with DCIS.

show abstract

“…Not only is telomerase expressed in over 90% of ovarian cancers, telomerase activity has also been shown to correlate well with ovarian tumor aggressiveness or stage [4,25,[37][38][39][40]. Although information about telomerase regulation is incomplete, various studies propose a complex model of regulation [1,10,12,13].…”

Section: Discussionmentioning

confidence: 99%

“…To quantitatively detect changes in telomerase levels, all cells were assayed for telomerase activity using the telomerase polymerase chain reaction-enzyme-linked immunosorbent assay (PCR-ELISA) (Roche Molecular Biochemicals, Indianapolis, IN), as described previously [36] and according to the manufacturer's instructions. This assay has been demonstrated to be as sensitive as the radioactive, telomere repeat amplification protocol (TRAP) assay [37][38][39][40][41][42][43][44]. Briefly, cells were washed with DPBS, trypsinized, counted, and centrifuged at 500g for 5 min.…”

Section: Methodsmentioning

confidence: 99%

Phosphoinositide 3-Kinase/AKT1 Pathway and Human Ovarian Cancer

Cheng¹

2001

View full text Add to dashboard Cite

SUPPLEMENTARY NOTESReport contains color Extensive studies have demonstrated that the Akt pathway is essential for cell survival and anti-apoptosis; however, alterations of Akt in human malignancy have not been documented. We have recently demonstrated significantly increased AKT1 and AKT2 kinase activity in primary ovarian carcinomas. We have also shown that PI3K is frequently activated in the specimens with activation of Akt. The majority of cases with PI3K/Akt activation are late stage and high grade. The biological significance of AKT 1 activation in human cancer was demonstrated by malignant transformation of NIH 3T3 cells transfected with constitutively active AKT1, but not cells transfected with wild type AKT1. Moreover, inhibition of PI3K/Akt pathway inhibits cell growth and induces apoptosis in human ovarian cancer cell lines. We have also observed that estrogen receptor (ER)cc interacts and activates PI3K/Akt pathway. PI3K/Akt feedback regulates ERa by phosphorylation of serine-167 of ERa. These data indicate that AKT1 kinase, which is frequently activated in human cancer, is a determinant in oncogenesis and a potential target for cancer intervention. Appendices 6 SUBJECT TERMS INTRODUCTION:The purpose of this project is to: 1) Determine the incidence and clinical significance of PI3K/AKT1 alterations in ovarian cancer; 2) Determine the role of overexpression of active and wild type PI3K and AKT1 in ovarian surface epithelial cell transformation and 3) Determine PI3K and AKT1 as targets for ovarian cancer intervention BODY:During the current budget year, we focused our efforts on the examination of incidence and clinical significance of PI3K/AKT1 alterations in human ovarian cancer and PI3K/AKT1 as a potential target for ovarian cancer intervention. I. PI3K/AKT1 is frequently activated in human primary ovarian cancer.Extensive studies have demonstrated that the Akt pathway is essential for cell survival and antiapoptosis (1); however, alterations of Akt in human malignancy have not been documented. Total 91 ovarian tumor specimens have been examined for protein expression and kinase activity of AKT 1. Activation of PI3K and AKT1 was observed in 39.3% tumor examined, however, elevated AKT1 protein level was only detected in 8.3% (2, see Appendix). We have also looked at PTEN, a tumor suppressor gene encoding dual phosphatase that dephosphorylates PI3K products (PI3,4,5P3) and inhibits AKT1 activity (3), alterations in this series of tumors. Three cases showed PTEN downregulation. These data suggest that PI3K activation is primary reason to result in elevated AKT1 kinase levels in human ovarian cancer. The majority of the tumors with PI3K/AKT1 activation are late stages and high grades indicating that alterations of PI3K/AKT1 are associated with tumor progression rather than initiation. II. Expression of constitutively activated AKT1 results in malignant phenotype in NIH 3T3cells.It has been demonstrated that wild type AKT1 was unable to transform NIH 3T3 cells (4). To determine whether activation of AK...

show abstract

Telomerase activity correlates with tumor aggressiveness and reflects therapy effect in breast cancer

Cited by 108 publications

References 15 publications

Detection of lung cancer using weighted digital analysis of breath biomarkers

Detection of lung cancer using weighted digital analysis of breath biomarkers

Telomerase activity in ductal carcinoma in situ and invasive breast cancer

Phosphoinositide 3-Kinase/AKT1 Pathway and Human Ovarian Cancer

Contact Info

Product

Resources

About