Risk-reducing strategies for women carrying BRCA1/2 mutations with a focus on prophylactic surgery

Background

Women who have inherited mutations in the BRCA1 or BRCA2 genes have substantially elevated risks of breast and ovarian cancer. Mutation carriers have various options, including extensive and regular surveillance, chemoprevention and risk-reducing surgery. The aim of this review is to provide an up-to-date analysis and to subsequently summarise the available literature in relation to risk-reducing strategies, with a keen focus on prophylactic surgery.

Methods

The literature review is facilitated by Medline and PubMed databases. The cross-referencing of the obtained articles was used to identify other relevant studies.

Results

Prophylactic surgery (bilateral mastectomy, bilateral salpingo-oophorectomy or a combination of both procedures) has proved to be the most effective risk-reducing strategy. There are no randomised controlled trials able to demonstrate the potential benefits or harms of prophylactic surgery; therefore, the evidence has been derived from retrospective and short follow-up prospective studies, in addition to hypothetical mathematical models.

Based on the current knowledge, it is reasonable to recommend prophylactic oophorectomy for BRCA1 or BRCA2 mutation carriers when childbearing is completed in order to reduce the risk of developing breast and ovarian cancer. In addition, women should be offered the options of rigorous breast surveillance, chemoprevention with anti-oestrogens--especially for carriers of BRCA2--or bilateral prophylactic mastectomy.

Conclusion

The selection of the most appropriate risk-reducing strategy is not a straightforward task. The impact of risk-reducing strategies on cancer risk, survival, and overall quality of life are the key criteria considered for decision-making. Notably, various other factors should be taken into consideration when evaluating individual mutation carriers' individual circumstances, namely woman's age, morbidity, type of mutation, and individual preferences and expectations.

Although prospective randomised controlled trials concerned with examining the various interventions in relation to the woman's age and type of mutation are needed, randomisation is extremely difficult and rather deemed unethical given the current available evidence from retrospective studies.

Evidence for a tumour suppressor function of SETD2 in human breast cancer: a new hypothesis

BACKGROUND

SET domain containing protein 2 (SETD2) is a histone methyltransferase that is involved in transcriptional elongation. We previously demonstrated SETD2 to be a potential tumour suppressor gene in breast cancer. The aim of this study was to compare SETD2 expression in breast cancer with that in adjacent non-cancerous breast tissue (ANCT) in paired samples. A hypothesis is proposed that explains the mode of action of SETD2 as a tumour suppressor gene.

MATERIALS AND METHODS

Paired samples of tumour and adjacent non-cancerous tissue (ANCT) from 25 patients were analysed. The levels of transcription of SETD2 were determined using quantitative polymerase chain reaction and normalized against cytokeratin 19. Immunohistochemical staining with appropriate antibodies against SETD2 protein was also performed in selected samples.

RESULTS

Levels of SETD2 mRNA were significantly higher in ANCT when compared to those in tumour samples (p=0.01). Immunohistochemistry also demonstrated a higher protein expression in ANCT.

CONCLUSION

This study offers further evidence that SETD2 behaves like a tumour suppressor gene. Our hypothesis links SETD2 mode of action with telomerase regulation through human telomerase reverse transcriptase (hTERT). Several studies have emphasised the importance of histone methylation of hTERT promotor in telomerase regulation. SETD2 function of histone methylation could be the missing link in this chain which could explain the potential tumour suppressor function of SETD2.

The evolving role of radiofrequency ablation therapy of breast lesions

BACKGROUND

The potential for radiofrequency ablation (RFA) therapy is an area of increasing interest in the context of breast conserving therapy for breast cancer. This non surgical technique potentially provides a non invasive, cosmetically pleasing result that is preferable to surgeon and patient.

MATERIALS AND METHODS

A literature review was carried out facilitated by PubMed and Medline databases. Cross referencing of the obtained articles was used to identify other relevant studies. A total of 17 studies were reviewed.

RESULTS

RFA is emerging as a promising treatment for breast cancer. Pilot and phase II studies have shown RFA to be effective at ablation with few complications or adverse effects experienced by patients. However, complete ablation of tumours is still not achieved in all patients.

CONCLUSION

RFA represents a promising therapeutic modality for breast lesions. However, there is a clear need for further research and refinement of the procedure before it can be offered as a therapeutic alternative to surgical excision for operable breast cancer.

Tumour suppressor function of MDA-7/IL-24 in human breast cancer

Introduction

Melanoma differentiation associated gene-7 (MDA-7), also known as interleukin (IL)-24, is a tumour suppressor gene associated with differentiation, growth and apoptosis. However, the mechanisms underlying its anti-neoplastic activity, tumour-specificity and efficacy across a spectrum of human cancers have yet to be fully elucidated. In this study, the biological impact of MDA-7 on the behavior of breast cancer (BC) cells is evaluated. Furthermore, mRNA expression of MDA-7 is assessed in a cohort of women with BC and correlated with established pathological parameters and clinical outcome.

Methods

The human BC cell line MDA MB-231 was used to evaluate the in-vitro impact of recombinant human (rh)-MDA-7 on cell growth and motility, using a growth assay, wounding assay and electric cell impedance sensing (ECIS). Localisation of MDA-7 in mammary tissues was assessed with standard immuno-histochemical methodology. BC tissues (n = 127) and normal tissues (n = 33) underwent RNA extraction and reverse transcription, MDA-7 transcript levels were determined using real-time quantitative PCR. Transcript levels were analyzed against tumour size, grade, oestrogen receptor (ER) status, nodal involvement, TNM stage, Nottingham Prognostic Index (NPI) and clinical outcome over a 10 year follow-up period.

Results

Exposure to rh-MDA-7 significantly reduced wound closure rates for human BC cells in-vitro. The ECIS model demonstrated a significantly reduced motility and migration following rh-MDA-7 treatment (p = 0.024). Exposure to rh-MDA-7 was only found to exert a marginal effect on growth. Immuno-histochemical staining of human breast tissues revealed substantially greater MDA-7 positivity in normal compared to cancer cells. Significantly lower MDA-7 transcript levels were identified in those predicted to have a poorer prognosis by the NPI (p = 0.049) and those with node positive tumours. Significantly lower expression was also noted in tumours from patients who died of BC compared to those who remained disease free (p = 0.035). Low levels of MDA-7 were significantly correlated with a shorter disease free survival (mean = 121.7 vs. 140.4 months, p = 0.0287) on Kaplan-Meier survival analysis.

Conclusion

MDA-7 significantly inhibits the motility and migration of human BC cells in-vitro. MDA-7 expression is substantially reduced in malignant breast tissue and low transcript levels are significantly associated with unfavourable pathological parameters, including nodal positivity; and adverse clinical outcomes including poor prognosis and shorter disease free survival. MDA-7 offers utility as a prognostic marker and potential for future therapeutic strategies.

Recurrent cystic lymphangioma of the breast: case report and literature review

Cystic lymphangioma is a rare congenital lymphatic malformation. We report a case of a 37-year-old female with recurrent cystic lymphangioma of the breast which has progressively developed during pregnancy and breast feeding.

Surgical excision for B3 breast lesions diagnosed by vacuum-assisted core biopsy

The aim of this retrospective study was to assess whether open surgical excision is required following a B3 diagnosis on 11-gauge vacuum-assisted core biopsy (VACB) of radiologically indeterminate breast lesions.

PATIENTS AND METHODS

Twenty-four women with a histological diagnosis of the B3 category on VACB of radiologically indeterminate breast lesions were identified over a 3-year period. The VACB procedure was performed under stereotactic (n=21), ultrasound (n=2) or magnetic resonance imaging (MRI) (n=1) guidance using the Suros system. Nineteen patients underwent open surgical excision. The remaining 5 patients who had 'complete' removal of the radiological abnormality using VACB under ultrasound (n=2, papilloma) or stereotactic (n=4, atypical ductal hyperplasia) guidance were followed up clinically and radiologically.

RESULTS

The median patient age was 49 years. The disease status in three patients was upgraded to ductal carcinoma in situ at open surgical excision. The VACB showed atypical lobular hyperplasia in these 3 patients, associated with microcalcification (n=2) or mass lesion (n=1). No single case of upgrading to invasive breast cancer was identified in our series. The remaining patients (16 out of 19) had a benign biopsy. The upgrade to malignancy was significantly associated with the presence of atypical lobular hyperplasia, a BI-RADS category of 4 and incomplete removal of the radiological abnormality by VACB. After a mean follow-up of 18 months, no malignancy was detected in the 5 patients who did not undergo open surgical biopsy.

CONCLUSION

Open surgical excision is strongly recommended for atypical lobular hyperplasia identified in VACB specimens. VACB can be a safe alternative to surgery in the treatment of B3 lesions in selected cases, providing thorough multidisciplinary discussion has taken place.

Higher expression levels of SOCS 1,3,4,7 are associated with earlier tumour stage and better clinical outcome in human breast cancer

BACKGROUND

Suppressors of cytokine signaling (SOCS) are important negative feedback regulators of the JAK/STAT signaling pathway, and have been recently investigated for their role in the development of different cancers. In this study, we examined the expression of SOCS1-7 genes in normal and breast cancer tissue and correlated this with several clinico-pathological and prognostic factors.

METHODS

SOCS1-7 mRNA extraction and reverse transcription were performed on fresh frozen breast cancer tissue samples (n = 127) and normal background breast tissue (n = 31). Transcript levels of expression were determined using real-time PCR and analyzed against TNM stage, tumour grade and clinical outcome over a 10 year follow-up period.

RESULTS

SOCS1,4,5,6 and 7 expression decreased with increased TNM stage (TNM1 vs. TNM3 p = 0.039, TNM1 vs. TNM4 p = 0.016, TNM2 vs. TNM4 p = 0.025, TNM1 vs. TNM3 p = 0.012, and TNM1 vs. TNM3 p = 0.044 respectively). SOCS2 and 3 expression decreased with increased Nottingham Prognostic Index (NPI) (NPI1 vs. NPI3 p = 0.033, and NPI2 vs. NPI3 p = 0.041 respectively). SOCS7 expression decreased with higher tumour grade (Grade 3 vs. Grade 2 p = 0.037). After a median follow up period of 10 years, we found higher levels of SOCS1,2 and 7 expression among those patients who remained disease-free compared to those who developed local recurrence (p = 0.0073, p = 0.021, and p = 0.039 respectively). Similarly, we found higher levels of SOCS 2,4, and 7 expression in those who remained disease-free compared to those who developed distant recurrence (p = 0.022, p = 0.024, and p = 0.033 respectively). Patients who remained disease-free had higher levels of SOCS1 and 2 expression compared to those who died from breast cancer (p = 0.02 and p = 0.033 respectively). The disease free survival (DFS) and overall survival (OS) curves showed that higher levels of SOCS1, 3 and 7 were significant predictors of higher DFS (p = 0.015, p = 0.024 and 0.03 respectively) and OS (p = 0.005, p = 0.013 and p = 0.035 respectively). Higher levels of SOCS 4 were significant in predicting better OS (p = 0.007) but not DFS. Immunohistochemical staining of representative samples showed a correlation between SOCS1, 3, 7 protein staining and the SOCS1, 3, 7 mRNA expression.

CONCLUSION

Higher mRNA expression levels of SOCS1, 3, 4 and 7 are significantly associated with earlier tumour stage and better clinical outcome in human breast cancer.

Oncological outcome and patient satisfaction with skin-sparing mastectomy and immediate breast reconstruction: a prospective observational study

BACKGROUND

The management of early breast cancer (BC) with skin-sparing mastectomy (SSM) and immediate breast reconstruction (IBR) is not based on level-1 evidence. In this study, the oncological outcome, post-operative morbidity and patients' satisfaction with SSM and IBR using the latissimus dorsi (LD) myocutaneous flap and/or breast prosthesis is evaluated.

METHODS

137 SSMs with IBR (10 bilateral) were undertaken in 127 consecutive women, using the LD flap plus implant (n = 85), LD flap alone (n = 1) or implant alone (n = 51), for early BC (n = 130) or prophylaxis (n = 7). Nipple reconstruction was performed in 69 patients, using the trefoil local flap technique (n = 61), nipple sharing (n = 6), skin graft (n = 1) and Monocryl mesh (n = 1). Thirty patients underwent contra-lateral procedures to enhance symmetry, including 19 augmentations and 11 mastopexy/reduction mammoplasties. A linear visual analogue scale was used to assess patient satisfaction with surgical outcome, ranging from 0 (not satisfied) to 10 (most satisfied).

RESULTS

After a median follow-up of 36 months (range = 6-101 months) there were no local recurrences. Overall breast cancer specific survival was 99.2%, 8 patients developed distant disease and 1 died of metastatic BC. There were no cases of partial or total LD flap loss. Morbidities included infection, requiring implant removal in 2 patients and 1 patient developed marginal ischaemia of the skin envelope. Chemotherapy was delayed in 1 patient due to infection. Significant capsule formation, requiring capsulotomy, was observed in 85% of patients who had either post-mastectomy radiotherapy (PMR) or prior radiotherapy (RT) compared with 13% for those who had not received RT. The outcome questionnaire was completed by 82 (64.6%) of 127 patients with a median satisfaction score of 9 (range = 5-10).

CONCLUSION

SSM with IBR is associated with low morbidity, high levels of patient satisfaction and is oncologically safe for T(is), T1 and T2 tumours without extensive skin involvement.

Evidence of a tumour suppressor function for DLEC1 in human breast cancer

DLEC1 (deleted in lung and oesophageal cancer), located on 3p22.3, is a candidate tumour suppressor gene in lung, esophageal, and renal cancer. The aim of this study was determine whether the mRNA expression levels of DLEC1 were consistent with a tumour suppressive function.

MATERIALS AND METHODS

A total of 153 samples were analysed. The levels of transcription of DLEC1 were determined using quantitative PCR and normalised against (CK19). Transcript levels within breast cancer specimens were compared to normal background tissues.

RESULTS

Levels of transcription were lower [corrected] in tumour samples compared to adjacent non cancerous tissue (ANCT) samples but this was not statistically significant (median 0.167 vs. 0.03; p=0.138). DLEC1 expression levels were significantly lower in samples from patients who developed metastasis, local recurrence, or died of breast cancer when compared to those who were disease free for >10 years (p=0.041).

DISCUSSION

These findings are consistent with a possible tumour suppressor function of DLEC1 in breast cancer.

Gene Transcripts in the Tumor Suppressor Region of Chromosome 3 (3p21)

Background:There is increasing evidence that the short arm of chromosome 3 has a tumour suppressor region that has been associated with permanent growth arrest of tumour cells. We have identified 9 closely related genes in this region (CCDC12, KLH9, KLH18, MYL3, NBEAL2, PTPN23, SCAP, SETD2, and TESSP2) located which could be possible candidates for tumour suppressor genes (TSG).Our objective was to determine, using quantitative PCR, whether the mRNA expression levels of these genes were consistent with a tumour suppressive function in human breast cancer.Methods:A total of 153 samples were analysed. The levels of transcription of all 9 genes were determined using quantitative PCR and normalized against (CK19).Transcript levels within breast cancer specimens were compared with non-cancerous breast tissue and analyzed against conventional pathological parameters and clinical outcome over a 10 year follow-up period.Results:Quantification of CCDC12, KLH9, KLH18, MYL3, NBEAL2, PTPN23, and SCAP mRNA expression after CK19 normalisation showed no statistically significant difference between malignant and normal breast tissue (p=0.23, 0.46, 0.3, 0.141, 0.8, 0.696, and 0.11 respectively). The mRNA expression of TESSP2 was higher in normal samples compared with malignant lesions (347 vs. 35, p=0.0061) but showed no significant associations with clinical outcome.The levels of SETD2 mRNA were significantly lower in malignant samples (406 vs. 17, p=0.0345) and decreased with increasing tumour stage. SETD2 expression levels were significantly lower in samples from patients who developed metastasis, local recurrence, or died from breast cancer when compared to those who were disease free for > 10 years (p=0.041).Conclusion:These findings are consistent with a possible tumour suppressor function of SETD2 in human breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6139.

Suppressors of Cytokine Signaling and Their Role in Human Breast Cancer

BACKGROUND:Suppressors of cytokine signaling (SOCS) are important negative feedback regulators of the JAK/STAT signaling pathway, and have been recently investigated for their role in the development of different cancers. In this study, we examined the expression of SOCS 1-7 genes in normal and breast cancer tissue and correlated this with several clinico-pathological and prognostic factors.PATIENTS AND METHODS:SOCS 1-7 mRNA extraction and reverse transcription were performed on breast cancer tissue samples (n= 127) and normal background breast tissue (n= 31). Transcript levels of expression were determined using real-time PCR and analyzed against TNM stage, tumour grade and clinical outcome over a 10 year follow-up period.RESULTS:SOCS 1,4,5,6 and 7 expression decreased with increased TNM stage (TNM1 vs. TNM3 p= 0.039, TNM1 vs. TNM4 p= 0.016, TNM1 vs. TNM3 p= 0.012 and TNM1 vs. TNM3 p= 0.044 respectively). SOCS 2 and 3 expression decreased with increased Nottingham Prognostic Index (NPI) (NPI1 vs. NPI3 p=0.033 and NPI2 vs. NPI3 p=0.041 respectively). SOCS-7 expression decreased with higher tumour grade (Grade 3 vs. Grade 2 p=0.037). After a median follow up period of 10 years, we found higher levels of SOCS 1, 2 and 7 expression among those patients who remained disease-free compared to those who developed local recurrence (p= 0.0073, p= 0.021 and p= 0.039 respectively). Similarly, we found higher levels of SOCS 2, 4 and 7 expression in those who remained disease-free compared to those who developed distant recurrence (p= 0.022, p=0.024 and p= 0.033 respectively). Patients who remained disease-free had higher levels of SOCS 1 and 2 expression compared to those who died from breast cancer (p= 0.02 and p=0.033 respectively). The disease free survival (DFS) and overall survival (OS) curves showed that higher levels of SOCS 1, 3 and 7 were significant predictors of higher DFS (p=0.015, p=0.024 and p=0.03 respectively) and OS (p=0.005, p=0.013 and p= 0.035 respectively). Higher levels of SOCS 4 were significant in predicting better OS (p=0.007) but not DFS.CONCLUSIONHigher mRNA expression levels of SOCS 1, 3, 4 and 7 are significantly associated with earlier tumour stage and better clinical outcomes in human breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3157.

Oncological Outcome and Patient's Satisfaction of Skin-Sparing Mastectomy and Immediate Breast Reconstruction: A Prospective Observational Study

INTRODUCTION: The management of early breast cancer with skin-sparing mastectomy (SSM) and immediate breast reconstruction (IBR) is not based on evidence from randomised controlled trials. The purpose of this study is to evaluate the oncological safety, post-operative morbidity and patients' satisfaction with SSM and IBR using the latissimus dorsi (LD) myocutaneous flap and/or breast prosthesis. METHODS: One hundred and twenty five consecutive women underwent 137 SSMs with IBR (12 bilateral), using the LD flap plus implant (n=85) or implant alone (n=42), indications included breast cancer (n=130)and prophylaxis (n=7). Most tumours (99.2%) were Tis, T1, or T2 and only one tumour was T3 stage. Nipple reconstruction was performed in 69 patients, using a small local flap technique (n=61), nipple sharing (n=6), free skin graft (n=1) or Monocryl mesh (n=1). Thirty patients underwent contra-lateral surgery in order to optimise symmetry, including 19 augmentations and 11 mastopexy/reduction mammoplasties. Patient satisfaction with the outcome of surgery was assessed on a linear visual analogue scale ranging from 0 (not satisfied) to 10 (most satisfied). RESULTS: There was no local recurrence (LR) after a mean follow-up of 33.2 months (range=3-98 months). Overall survival was 99.2%, seven patients developed distant disease and one patient died of metastatic breast cancer. No case of partial or total LD flap loss was observed. Morbidities included infection, requiring implant removal in two patients and one patient developed marginal ischaemia of the skin envelope. Significant capsule formation, requiring capsulotomy, was observed in 87% of patients who had either PMR or prior RT compared with 13% for those who did not have RT. Eighty two (65.6%) of 125 patients completed the questionnaire with a median satisfaction scores of 9 (range=5-10). CONCLUSION: SSM with IBR is associated with low morbidity, high levels of patient satisfaction and is oncologically safe for T(is), T1 and T2 tumours without extensive skin involvement.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3113.

The mRNA expression of SETD2 in human breast cancer: correlation with clinico-pathological parameters

Background

SET domain containing protein 2 (SETD2) is a histone methyltransferase that is involved in transcriptional elongation.

There is evidence that SETD2 interacts with p53 and selectively regulates its downstream genes. Therefore, it could be implicated in the process of carcinogenesis. Furthermore, this gene is located on the short arm of chromosome 3p and we previously demonstrated that the 3p21.31 region of chromosome 3 was associated with permanent growth arrest of breast cancer cells. This region includes closely related genes namely: MYL3, CCDC12, KIF9, KLHL18 and SETD2. Based on the biological function of these genes, SETD2 is the most likely gene to play a tumour suppressor role and explain our previous findings.

Our objective was to determine, using quantitative PCR, whether the mRNA expression levels of SETD2 were consistent with a tumour suppressive function in breast cancer. This is the first study in the literature to examine the direct relationship between SETD2 and breast cancer.

Methods

A total of 153 samples were analysed.

The levels of transcription of SETD2 were determined using quantitative PCR and normalized against (CK19).

Transcript levels within breast cancer specimens were compared to normal background tissues and analyzed against conventional pathological parameters and clinical outcome over a 10 year follow-up period.

Results

The levels of SETD2 mRNA were significantly lower in malignant samples (p = 0.0345) and decreased with increasing tumour stage.

SETD2 expression levels were significantly lower in samples from patients who developed metastasis, local recurrence, or died of breast cancer when compared to those who were disease free for > 10 years (p = 0.041).

Conclusion

This study demonstrates a compelling trend for SETD2 transcription levels to be lower in cancerous tissues and in patients who developed progressive disease. These findings are consistent with a possible tumour suppressor function of this gene in breast cancer.

The mRNA expression of SATB1 and SATB2 in human breast cancer

BACKGROUND

SATB1 is a nuclear protein that has been recently reported to be a 'genome organizer' which delineates specific epigenetic modifications at target gene loci, directly up-regulating metastasis-associated genes while down-regulating tumor-suppressor genes. In this study, the level of mRNA expression of SATB1 and SATB2 were assessed in normal and malignant breast tissue in a cohort of women with breast cancer and correlated to conventional clinico-pathological parameters.

MATERIALS AND METHODS

Breast cancer tissues (n = 115) and normal background tissues (n = 31) were collected immediately after excision during surgery. Following RNA extraction, reverse transcription was carried out and transcript levels were determined using real-time quantitative PCR and normalized against beta-actin expression. Transcript levels within the breast cancer specimens were compared to the normal background tissues and analyzed against TNM stage, nodal involvement, tumour grade and clinical outcome over a 10 year follow-up period.

RESULTS

The levels of SATB1 were higher in malignant compared with normal breast tissue (p = 0.0167). SATB1 expression increased with increasing TNM stage (TNM1 vs. TNM2 p = 0.0264), increasing tumour grade (grade1 vs. grade 3 p = 0.017; grade 2 vs. grade 3 p = 0.0437; grade 1 vs. grade 2&3 p = 0.021) and Nottingham Prognostic Index (NPI) (NPI-1 vs. NPI-3 p = 0.0614; NPI-2 vs. NPI-3 p = 0.0495). Transcript levels were associated with oestrogen receptor (ER) positivity (ER(-) vs. ER(+) p = 0.046). SABT1 expression was also significantly correlated with downstream regulated genes IL-4 and MAF-1 (Pearson's correlation coefficient r = 0.21 and r = 0.162) and SATB2 (r = 0.506). After a median follow up of 10 years, there was a trend for higher SATB1 expression to be associated with shorter overall survival (OS). Higher levels of SATB2 were also found in malignant compared to background tissue (p = 0.049). SATB2 expression increased with increasing tumour grade (grade 1 vs. grade 3 p = 0.035). SATB2 was associated with ER positivity (ER(-) vs. ER(+) p = 0.0283) within ductal carcinomas. Higher transcript levels showed a significant association with poorer OS (p = 0.0433).

CONCLUSION

SATB1 mRNA expression is significantly associated with poor prognostic parameters in breast cancer, including increasing tumour grade, TNM stage and NPI. SATB2 mRNA expression is significantly associated with increasing tumour grade and poorer OS. These results are consistent with the notion that SATB1 acts as a 'master genome organizer' in human breast carcinogenesis.

Oestrogen-synthesising enzymes and breast cancer

There is a large and compelling body of epidemiological and experimental evidence that oestrogens are the fuel behind the aetiology of breast cancer. The carcinogenic effects of oestrogen are postulated to be mediated by: the stimulation of cellular proliferation through their receptor-mediated hormonal activity. Other mechanisms include; direct genotoxic effects by increasing mutation rates through a cytochrome P450-mediated metabolic activation and induction of aneuploidy. The local biosynthesis of oestrogens, especially in postmenopausal women as a result of the interactions of various enzymes, is believed to play a very important role in the pathogenesis and development of hormone dependent breast carcinoma. The over-expression of such enzymes seems to be associated with the development of a more aggressive disease process, a poorer outcome and increased local and distant recurrences.

Expression of MDA7/IL-24 human breast cancer and the molecular impact

Abstract #2060

INTRODUCTION. MDA-7 (melanoma differentiation associated gene-7), also known as IL-24, was initially identified from cancer cells and was found to be up-regulated in melanoma cells. Forced expression of MDA7 in cancer cells was found to be growth inhibitory. MDA7/IL-24 operates in cells via its receptor, MDA7R/IL-24R, which includes at least the IL-20Rα and IL-20Rβ complex and the IL-22R and IL20Rβ complex. The present study investigated the impact of MDA7 on the growth and motility of breast cancer cells and the clinical relevance of MDA7 expression in mammary tumour tissues.
 MATERIALS AND METHODS. Human breast cancer cell lines MDA MB-231 and MCF-7 were used for in vitro testing. The response of cancer cells to rhMDA7 in growth and cellular motility was determined using growth assay and ECIS (electric cell impedance sensing, and confirmed by wounding assay). Localisation of MDA7 in mammary issues was assessed using conventional immunohistochemical method. Levels of MDA7 transcript in fresh frozen breast tissues were determined using quantitative PCR analysis and analysed against clinical and pathological information.
 RESULTS. Recombinant human MDA-7 only had a marginal effect on the in vitro growth of the breast cancer cell lines used. However, rhMDA had a significant effect on the migration of breast cancer cells. Cells treated with rhMDA-7 showed a slower rate of migration (electrical resistance 80.1±24.3Ω), when compared with control cells (130±24.3Ω) (p=0.024). Normal mammary epithelial cells showed a good degree of staining of MDA-7, a staining greatly reduced in cancer cells. Using the Nottingham Prognostic Index as a predictor of prognosis, tumours from patients with poor prognosis showed a significantly lower level of MDA-7 transcript compared with tumours from those with good prognosis (p=0.049). A significant difference was seen between tumours from patients who died of breast cancer and tumours from patients who remained disease free (p=0.035), the later showing a higher levels of MDA7 transcript. Using the Kaplan-Meier survival analysis, it was revealed that low levels of MDA-7 were significantly correlated with a shorter disease free survival (mean survival for low level group 121.7 (108.5-134.9) months compared with high levels 140.4 (133.7 – 147.1, 95% CI) months, p=0.0287. ER positive tumours showed a lower but levels of MDA-7 expression compared with ER-negative tumours, although this was not statistically significant (p=0.094).
 CONCLUSIONS. MDA-7 is a potential regulator of cellular motility of breast cancer cells. The aberrant expression of the molecule is linked to the prognosis and long term survival of patients, indicating the potential clinical implication of MDA-7 in cancer therapies.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 2060.

SATB1: a 'master genome organizer' in mammary carcinogenesis

Abstract #3070

Background: SATB1 is a nuclear protein that has been recently reported to be a 'genome organizer' that delinates specific epigenetic modifications at target gene loci, directly up-regulating metastasis-associated genes while down-regulating tumor-suppressor genes. This study aimed to examine the level of mRNA expression of SATB1 gene in normal and malignant breast tissue and correlate the level to the clinico-pathological parameters.
 Material and Methods: One hundred and fifteen breast cancer tissue and 31 normal breast tissues were analyzed. Levels of transcription of SATB1 were determined using real-time quantitative PCR and were analyzed against TNM stage, nodal involvement, tumor grade and clinical outcome.
 Results: The levels of SATB1 mRNA were significantly higher in malignant compared with normal breast tissue (p=0.0167). The expression of SATB1 mRNA was demonstrated to increase with increasing TNM stage (TNM1 vs. TNM2, p=0.0264; TNM2 vs. TNM3, p=0.024) and increasing tumor grade (grade 1 vs. grade 3, p=0.017; grade 2 vs. grade 3, p=0.0437; grade 1 vs. grade 2&3, p=0.021). After a median follow up of 10 years, there was a trend for tumors with higher SATB1 expression levels to be associated with shorter overall survival times.
 Discussion: These results are consistent with the notion that SATB1 acts as the 'master genome organizer' in tumorigenesis of human breast cancer.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 3070.

Prognostic utility of glycosyltransferase expression in breast cancer

BACKGROUND

The post-translational modification of proteins, including glycosylation, is known to differ between normal and tumour cells. In this study, the expression profile of two glycosyltranferases, UDP-N-acetyl-D-galactosamine: polypeptide N-acetylgalactosaminyltransferase-6 (ppGalNAc-T6) and alpha6-sialyl-transferase-I (ST6GalNAc-I) was assessed, in a cohort of women with breast cancer.

PATIENTS AND METHODS

Breast cancer tissues (n=127) and normal background tissues (n=33) were collected immediately after excision during surgery. Following RNA extraction, reverse transcription was carried out and transcript levels were determined using real-time quantitative PCR and normalized against glyceraldehyde-3-phosphate dehydrogenase (GAPDH) expression. Transcript levels within the breast cancer specimens were compared to the normal background tissues and analyzed against conventional pathological parameters and clinical outcome over a 10 year follow-up period.

RESULTS

Significantly higher levels of ppGalNAc-T6 were found in the breast cancer specimens compared to the background tissue (p=0.015). There was a non-significant trend for levels to increase with the Nottingham Prognostic Index (NPI) and TNM stage and those who died from breast cancer. ST6GalNAc-I expression was associated with better prognosis, reaching significance when comparing patients who remained disease free to those with distant recurrence (p=0.0096). The relationship approached significance when comparing NPI 2 to NPI 3 (p=0.058) and disease free patients to non-disease free patients (p=0.052) or those who died of breast cancer (p=0.060). For both enzymes a significant association with ductal type was found.

CONCLUSION

Expression of ppGalNAc-T6 is significantly higher in breast cancer compared to 'normal'/benign breast tissue samples. ST6GalNAc-I expression in breast cancer is associated with better prognosis.

Osteopontin expression profiles predict pathological and clinical outcome in breast cancer

BACKGROUND

Osteopontin (OPN) overexpression in breast cancer has been associated with adverse pathological and clinical outcomes. In this study, the OPN expression profiles were examined in a cohort of breast cancer patients.

PATIENTS AND METHODS

RNA extraction and reverse transcription were performed on breast carcinomas (n = 127) and normal tissues (n = 33). Transcript levels were determined using real-time PCR.

RESULTS

The OPN-a levels decreased with increasing TNM stage and worse clinical outcome. The OPN-b levels increased with tumour grade and Nottingham Prognostic Index (NPI) stage, were higher in patients who died of breast cancer than in those who were disease-free after 10 years and predicted disease-free survival. The OPN-c expression was associated with tumour grade and poor prognosis. Furthermore, the expression levels predicted local recurrence, disease-free survival and bone metastases.

CONCLUSION

OPN expression profiles are significantly associated with tumour grade, stage and patient prognosis in breast cancer. OPN-c is likely to be of particular utility as a prognostic marker and should be included in future validation studies.

Evidence of a tumour suppressive function of E2F1 gene in human breast cancer

BACKGROUND

The E2F family of transcription factors are key regulators of genes involved in cell cycle progression, cell fate determination, DNA damage repair and apoptosis. E2F1 is unique in that it contributes both to the control of cellular proliferation and cellular death. Furthermore, unlike other E2Fs, E2F1 responds to various cellular stresses. This study aimed to examine the level of mRNA expression of E2F1 gene in normal and malignant breast tissue and correlate the level of expression to tumour stage.

MATERIALS AND METHODS

One hundred and twenty-seven breast cancer tissue and 33 normal tissues were analyzed. Levels of transcription of E2F1 were determined using real-time quantitative PCR, normalized against CK19. Levels of expression were analyzed against TNM stage, nodal involvement, tumour grade and distant metastasis.

RESULTS

The levels of E2F1 mRNA were lower in malignant tissues. They declined further with increasing TNM stage. This became statistically significant when TNM stages 3 and 4 were compared to TNM stages 1 and 2 disease (TNM1 vs. TNM3 p = 0.032; TNM1 vs. TNM4 p = 0.032; TNM2 vs. TNM3 p = .019; TNM2 vs. TNM4 p = 0.021). The levels of E2F1 also fell with increasing tumour grade, when comparing grade 2 and 3 with grade 1, however, the differences were not statistically significant.

CONCLUSION

These results are highly suggestive of the role of E2F1 as a tumour suppressive gene in human breast cancer.

The role of Herceptin in early breast cancer

Herceptin is widely regarded as the most important development in the treatment of breast cancer since Tamoxifen and the development of the multidisciplinary team (MDT). It is particularly exciting from an oncological polint of view as it represents success in the emerging field of specific targeted therapies to specific molecular abnormalities in tumour cells. This review will focus on the nature of the Her2 overexpression and the role of herceptin in the treatment of early breast cancer.

Paraneoplastic cerebellar degeneration as a presentation of breast cancer - a case report and review of the literature

Paraneoplastic cerebellar degeneration is part of a rare spectrum of neurological syndromes whereby gynaecological, lung or breast cancers present primarily with neurological manifestations. The presence of onconeural antibodies and PET scanning help in the challenging diagnosis of these conditions but despite the treatment of the primary cancer, the prognosis for the neurological symptoms is poor.

The clinical significance of sentinel lymph node micrometastasis in breast cancer

INTRODUCTION

The advent of sentinel lymph node biopsy (SLNB) and improvements in histopathological and molecular analysis have increased the rate at which micrometastases (MM) are identified. However, their significance has been the subject of much debate. In this article we review the literature concerning axillary lymph node (ALN) MM, with particular reference to SLNB. The controversies regarding histopathological assessment, clinical relevance and management implications are discussed.

METHODS

Literature review facilitated by Medline and PubMed databases.

RESULTS

Published studies have reported divergent results regarding the significance and implications of ALN MM in general and sentinel lymph node (SLN) MM in particular. Some studies demonstrate no associations, whilst others have found these to be indicators of poor prognosis, associated with non-SLN involvement, in addition to local and distant failure. Absolute consensus regarding the optimal analytical technique for SLNs has yet to be reached, particularly concerning immunohistochemical (IHC) techniques targeting cytokeratins and the utility of contemporary molecular analysis.

CONCLUSION

SLN MM are likely to represent an incremental detriment to prognosis and increased risk of non-SLN involvement, despite only modest up-staging within current classification systems. In the absence of level-1 guidance concerning the management of women with SLN MM, each case requires discussion with regard to other tumour and patient related factors in the context of the multidisciplinary team. Randomized studies are required to evaluate the prognostic significance and optimal management of each category of tumour burden within the SLN. The identification of MM remains highly dependent on the analytical technique employed and there exists potential for stage migration and impact on management decisions.

Lymphangiogenesis and lymph node metastasis in breast cancer

Introduction

There have been few studies on lymphangiogenesis in the past due to the lack of specific lymphatic endothelial markers, and lymphatic-specific growth factors. Recently, these limitations have been relieved by the discovery of a small number of potential lymphatic-specific markers. The relationship between lymphangiogenesis and regional or distant metastasis has not previously been investigated in humans. Using these lymphatic markers, it is possible to explore the relationship between lymphangiogenesis and tumour metastasis. This study indirectly quantified lymphangiogenesis by measuring mRNA expression of all seven lymphatic markers described above in breast cancers and correlated these markers with lymphatic involvement and survival.

The cDNA from 153 frozen archived breast samples were analysed with Q-PCR for all seven lymphangiogenic markers. This was correlated with various prognostic factors as well as patient survival.

Results

There was significantly greater expression of all 7 markers in malignant compared to benign breast tissue. In addition, there was greater expression in lymph node positive/grade 3 tumours when compared to lymph node negative/grade 1 tumours. In 5 of the markers, there was a greater expression in poor NPI prognostic tumours when compared to favourable prognostic tumours which was not statistically significant. There was no association between recurrence risk and lymphangiogenic marker expression.

Conclusion

In summary, the findings from this study show that lymphangiogenesis, measured by specific lymphatic marker expression, is higher in breast cancers than in normal breast tissue. Secondly, breast cancers which have metastasised to the regional lymphatics show higher expression compared to those which have not, although the individual differences for all five markers were not statistically significant.

The utility of MRI for the screening and staging of breast cancer

INTRODUCTION & BACKGROUND

Contrast-enhanced magnetic resonance imaging (MRI) of the breast has been recently introduced as a potential clinical tool for the detection, diagnosis, staging and management of breast cancer. In this article, we consider the established and evolving roles of MRI with particular reference to screening in high risk women and staging of the primary tumour. Controversies are discussed in the context of the tumour biology and natural history of breast cancer.

METHODS

Articles were identified by searches of PubMed and MEDLINE up to October 2007.

RESULTS

Contrast-enhanced MRI is an effective tool for screening women at high risk of breast cancer. However, randomized trials have yet to demonstrate a reduction in mortality. MRI can also facilitate local staging, in particular, the evaluation of ipsilateral multicentric or multifocal lesions and synchronous contralateral disease which may be 'missed' by conventional imaging. However, efficacy with respect to clinically relevant and patient oriented end-points has yet to be addressed in the context of clinical trials.

CONCLUSIONS

In women at high risk of breast cancer, screening MRI should be used in conjunction with published guidelines. In women with newly diagnosed breast cancer, the utility of MRI is less clearly defined and should be restricted to selected cases within the multidisciplinary setting.

Expression of the cell to cell adhesion molecule, ALCAM, in breast cancer patients and the potential link with skeletal metastasis

The activated leukocyte cell adhesion molecule (ALCAM) is involved in cell migration and adhesion. Decreased levels of ALCAM expression in breast cancer tissue are known to correlate with poor prognosis. The current study specifically investigated the ALCAM expression in tumours which developed skeletal metastasis. Fresh frozen primary breast cancer tissues (n=234) and non-neoplastic mammary tissue (n=34) were used. The distribution and location of ALCAM was assessed using immunohistochemical methods and the level of ALCAM was determined using quantitative RT-PCR. The results were analysed against the clinical and pathological data. ALCAM staining was largely membranous and cytoplasmic in normal epithelial cells and is significantly stronger than in cancer cells (p=0.023) and patients who develop skeletal metastasis (p=0.048). The ALCAM transcript levels were lowest in patients with skeletal metastasis (p=0.0048) but were also significantly lower in patients who developed local recurrence (p=0.040) and in those who died from breast cancer (p=0.0075). Patients with moderate and poor prognostic indices have a lower level than those with a good index (p=0.05 and p=0.0089 respectively) and ER-positive tumours show a lower level than ER-negative (p=0.043). Ductal carcinomas, 86% of the cohort, have a similar pattern of changes with skeletal metastasis patients having significantly lower levels (p=0.015). This study has, for the first time, shown that patients who develop skeletal metastasis tend to have the lowest levels of ALCAM transcripts in their breast cancers, a finding potentially useful for clinical practice.

Mammographic breast density by area of residence: possible evidence of higher density in urban areas

OBJECTIVES

A comparison of mammographic breast densities of women living in London with those of women living in rural and suburban areas.

DESIGN AND METHODS

Using the standard four American College of Radiology Breast Imaging Reporting and Data System (BIRADS) categories of mammographic density, 318 mammograms of women from London and 654 mammograms of women from outside the capital aged 27-87 years who had received mammography at the Princess Grace Hospital, London, were assessed for density. The association between having any dense tissue and area of residence was assessed using both ordered and standard logistic regression, giving odds ratio estimates of relative risk of dense tissue adjusting for age.

RESULTS

Adjusting for age, London residents had significantly higher levels of density (OR = 1.32, 95% CI 1.04-1.70, p = 0.02). The major difference occurred in the age group 45-54 years and was most strongly manifested as a higher rate in London for density of 25% or more (BIRADS categories 2-4) as compared to almost entirely fatty (BIRADS 1) (OR = 2.22, 95% CI 1.05-4.68, p = 0.035).

CONCLUSION

The higher density is likely to be due to a different prevalence of risk factors in the London population. This study cannot ascertain the reason for the higher density in this urban population, but the result is a cause for concern given that screening uptake is lower in London. Increased attention to screening in urban areas and attention to screening quality for dense breast tissue might be prudent.

Cyclooxygenase-2 mRNA expression correlates with aromatase expression in human breast cancer

INTRODUCTION

The cyclooxygenase-2 (COX-2), responsible for the conversion of arachidonic acid into prostaglandin (PG) E2, is known to increase intracellular cAMP and estrogen production in malignant breast tissue. The aromatase enzyme complex is responsible for local production of estrogens in breast cancer. Increasing evidence supports a role for COX-2 in upregulation of aromatase activity. The aim of this study was to examine the relationship between COX-2 and aromatase mRNA expression in human breast cancer.

METHODS

A total of 160 breast samples (127 tumor tissues and 33 normal tissues) were analyzed. Levels of transcription were determined using real-time quantitative PCR. COX-2 and aromatase mRNA expression were normalized against CK19. Levels of expression of COX-2 were correlated with those of aromatase using Pearson's correlation method.

RESULTS

Levels of expression of COX-2/CK19 of both benign and malignant tissues were positively correlated with aromatase/CK19 transcript levels (correlation coefficient = +0.536, P < 0.0001). When we compared levels of expression of both genes in malignant samples only, there was a highly significant positive correlation (r = +0.611, P < 0.00001).

CONCLUSION

This study demonstrates a strong positive relationship between COX-2 and aromatase mRNA expression, and lends further support to the hypothesis that COX-2 is an upregulator of aromatase in breast tissue.

Current management of DCIS: a review

Ductal carcinoma in-situ (DCIS) is a heterogeneous disease, in terms of its radiological characteristics, histological morphology and molecular attributes. This diversity is reflected in its natural history and influences optimal treatment strategy. A significant proportion of DCIS lesions behave in a clinically benign fashion and do not progress to invasive disease. Reliable identification of these patients could allow treatment to be less radical or safely omitted. Management should be tailored to the individual within the context of a multidisciplinary team. Approaches such as biological profiling and molecular analysis represent an opportunity to improve our understanding of the tumour biology of this condition and rationalise its treatment. This article reviews the management strategies for DCIS in the context of recent randomized trials, including the role of sentinel lymph node biopsy, adjuvant radiotherapy and tamoxifen.

Evidence for a tumour suppressive function of IGF1-binding proteins in human breast cancer

The role of the insulin like growth factor (IGF) system in various human malignancies has been well established. The aim of this study was to determine the levels of mRNA expression of insulin-like growth factor-binding protein (IGFBP)-1, -3 and -7 genes in benign and malignant breast tissue and explore their relationship with various prognostic parameters.

MATERIALS AND METHODS

Breast cancer tissue (n=127) and normal background tissue (n-33) were prospectively collected and analysed for levels of IGFBP-1, -3 and -7 mRNA using real-time Q-PCR. mRNA levels were then analysed against tumour grade, nodal status, Nottingham prognostic index (NPI)/TNM stage and tumour type.

RESULTS

For IGFBP-1 and -3, mRNA expression was higher in normal tissue. This was significant for IGFBP-1 when comparing NPI 3 with NPI 1 (p=0.050) and the normal group (p=0.040). With respect to TNM analysis, there was less IGFBP-1 mRNA when comparing TNM 3 with normal (p=0.017), TNM 1 (p=0.047) and TNM 2 (p=0.019) tumours. This was also found when comparing TNM 4 samples with normal tissue (p=0.017), TNM 1 (p=0.046) and TNM 2 (p=0.019). For IGFBP-3 mRNA, there was less mRNA when comparing TNM 3 with TNM 1 (p= 0.017) and TNM 2 (p=0.050), and also less mRNA expression when comparing TNM 4 with TNM 1 (p=0.030). For IGFBP-7 mRNA, both TNM 1 (p=0.0077) and TNM 2 (p=0.015) had significantly more expression than TNM 3 samples.

CONCLUSION

This study supports the role of IGFBP-1, -3 and -7 as potential tumour suppressor genes in human breast cancer.

The role of cyclooxygenase-2 in breast cancer: review

There is a growing body of evidence that COX-2 expression s a fundamental step in breast cancer pathogenesis acting through prostaglandin-dependent and independent mechanisms. Epidemiological studies suggest that NSAIDs confer a moderate degree of benefit against breast cancer. However further work is required to establish how this enzyme system can be best manipulated for therapeutic benefit.