Comparison of visual and automated assessment of Ki-67 proliferative activity and their impact on outcome in primary operable invasive ductal breast cancer

Background:

Immunohistochemistry of Ki-67 protein is widely used to assess tumour proliferation, and is an established prognostic factor in breast cancer. There is interest in automating the assessment of Ki-67 labelling index (LI) with possible benefits in handling increased workload, with improved accuracy and precision.

Patients and methods:

Visual and automated assessment of Ki-67 LI and survival were examined in patients with primary operable invasive ductal breast cancer. Tissue microarrays (n=379 patients) immunostained for Ki-67 were scored visually and automatically with the Slidepath Tissue IA system.

Results:

Visual and automated Ki-67 LI were in excellent agreement (ICCC=0.96, P<0.001). On univariate analysis, visual (P<0.001) and automated Ki67 LI (P<0.05) were associated with cancer-specific survival in patients with invasive ductal breast cancer overall and in patients who received endocrine therapy (Tamoxifen) (P<0.01 for visual and P<0.05 for automated scoring).

Conclusion:

Automated assessment of Ki-67 LI would appear to be comparable to visual Ki-67 LI. However, automated Ki-67 LI assessment was inferior in predicting cancer survival in patients with breast cancer, including patients who received Tamoxifen.     

Cdc20 and securin overexpression predict short-term breast cancer survival

Background:

Cdc20 is an essential component of cell division and responsible for anaphase initiation regulated by securin degradation. Cdc20 function is strongly regulated by the spindle assembly checkpoint to ensure the timely separation of sister chromatids and integrity of the genome. We present the first results on Cdc20 in a large clinical breast cancer material.

Methods:

The study was based on 445 breast cancer patients with up to 20 years of follow-up (mean 10.0 years). DNA content was determined by image cytometry on cell imprints, and Cdc20 and securin immunohistochemistry on tissue microarrays of breast cancer tissue.

Results:

In our results, high Cdc20 and securin expression was associated with aneuploid DNA content. In prognostic analyses, high Cdc20 immunoexpression alone and in combination with high securin immunoexpression indicated aggressive course of disease and up to 6.8-fold (P<0.001) risk of breast cancer death. Particularly, high Cdc20 and securin immunoexpression identified a patient subgroup with extremely short, on average 2.4 years, breast cancer survival and triple-negative breast cancer (TNBC) subtype.

Conclusions:

We report for the first time the association of high Cdc20 and securin immunoexpression with extremely poor outcome of breast cancer patients. Our experience indicates that Cdc20 and securin are promising candidates for clinical applications in breast cancer prognostication, especially in the challenging prognostic decisions of TNBC.     

Tailoring treatment for ductal intraepithelial neoplasia of the breast according to Ki-67 and molecular phenotype

Background:

The post-surgical management of ductal intraepithelial neoplasia (DIN) of the breast is still a dilemma. Ki-67 labelling index (LI) has been proposed as an independent predictive and prognostic factor in early breast cancer.

Methods:

The prognostic and predictive roles of Ki-67 LI were evaluated with a multivariable Cox regression model in a cohort of 1171 consecutive patients operated for DIN in a single institution from 1997 to 2007.

Results:

Radiotherapy (RT) was protective in subjects with DIN with Ki-67 LI ≥14%, whereas no evidence of benefit was seen for Ki-67 LI <14%, irrespective of nuclear grade and presence of necrosis. Notably, the higher the Ki-67 LI, the stronger the effect of RT (P-interaction <0.01). Hormonal therapy (HT) was effective in both Luminal A (adjusted hazard ratio (HR)=0.56 (95% CI, 0.33–0.97)) and Luminal B/Her2neg DIN (HR 0.51 (95% CI, 0.27–0.95)).

Conclusion:

Our data suggest that Ki-67 LI may be a useful prognostic and predictive adjunct in DIN patients. The Ki-67 LI of 14% could be a potential cutoff for better categorising this population of women at increased risk for breast cancer and in which adjuvant treatment (RT, HT) should be differently addressed, independent of histological grade and presence of necrosis.     

Breast cancer patients' clinical outcome measures are associated with Src kinase family member expression

Background:

This study determined mRNA expression levels for Src kinase family (SFK) members in breast tissue specimens and assessed protein expression levels of prominent SFK members in invasive breast cancer to establish associations with clinical outcome. Ki67 was investigated to determine association between SFK members and proliferation.

Methods:

The mRNA expression levels were assessed for eight SFK members by quantitative real-time PCR. Immunohistochemistry was performed for c-Src, Lyn, Lck and Ki67.

Results:

mRNA expression was quantified in all tissue samples. SRC and LYN were the most highly expressed in malignant tissue. LCK was more highly expressed in oestrogen receptor (ER)-negative, compared with ER-positive tumours. High cytoplasmic Src kinase protein expression was significantly associated with decreased disease-specific survival. Lyn was not associated with survival at any cellular location. High membrane Lck expression was significantly associated with improved survival. Ki67 expression correlated with tumour grade and nuclear c-Src, but was not associated with survival.

Conclusions:

All eight SFK members were expressed in different breast tissues. Src kinase was highest expressed in breast cancer and had a negative impact on disease-specific survival. Membrane expression of Lck was associated with improved clinical outcome. High expression of Src kinase correlated with high proliferation.     

Evaluation of FLT-PET-CT as an imaging biomarker of proliferation in primary breast cancer

Background:

[¹⁸F]fluorothymidine (FLT) has been proposed as a positron emission tomography (PET)-imaging biomarker of proliferation for breast cancer. The aim of this prospective study was to assess the feasibility of FLT-PET-CT as a technique for predicting the response to neoadjuvant chemotherapy (NAC) in primary breast cancer and to compare baseline FLT with Ki-67.

Methods:

Twenty women with primary breast cancer had a baseline FLT-PET-CT scan that was repeated before the second cycle of chemotherapy. Expression of Ki-67 in the diagnostic biopsy was quantified. From the FLT-PET-CT scans lesion maximum and mean standardised uptake values (SUV_max, SUV_mean) were calculated.

Results:

Mean baseline SUV_max was 7.3, and 4.62 post one cycle of NAC, representing a drop of 2.68 (36.3%). There was no significant association between baseline, post chemotherapy, or change in SUV_max and pathological response to NAC. There was a significant correlation between pre-chemotherapy Ki-67 and SUV_max of 0.604 (P=0.006).

Conclusions:

Baseline SUV_max measurements of FLT-PET-CT were significantly related to Ki-67 suggesting that it is a proliferation biomarker. However, in this series neither the baseline value nor the change in SUV_max after one cycle of NAC were able to predict response as most patients had a sizeable SUV_max reduction.     

HER2/neu and Ki-67 expression predict non-invasive recurrence following breast-conserving therapy for ductal carcinoma in situ

Background:

Ductal carcinoma in situ (DCIS) is a non-invasive form of breast cancer that may progress to invasive cancer. Identification of factors that predict recurrence and distinguish DCIS from invasive recurrence would facilitate treatment recommendations. We examined the prognostic value of nine molecular markers on the risks of local recurrence (DCIS and invasive) among women treated with breast-conserving therapy.

Methods:

A total of 213 women who were treated with breast-conserving therapy between 1982 and 2000 were included; 141 received breast-conserving surgery alone and 72 cases received radiotherapy. We performed immunohistochemical staining on the DCIS specimen for nine markers: oestrogen receptor, progesterone receptor, Ki-67, p53, p21, cyclinD1, HER2/neu, calgranulin and psoriasin. We performed univariable and multivariable survival analyses to identify markers associated with the recurrence.

Results:

The rate of recurrence at 10 years was 36% for patients treated with breast-conserving surgery alone and 18% for women who received breast-conserving surgery and radiotherapy. HER2/neu+/Ki-67+ expression was associated with an increased risk of DCIS recurrence, independent of grade and age (HR=3.22; 95% CI: 1.47–7.03; P=0.003). None of the nine markers were predictive of invasive recurrence.

Conclusion:

Women with a HER2/neu/neu+/Ki67+ DCIS have a higher risk of developing DCIS local recurrence after breast-conserving surgery.     

Targeting focal adhesion turnover in invasive breast cancer cells by the purine derivative reversine

Background:

The dynamics of focal adhesion (FA) turnover is a key determinant for the regulation of cancer cell migration. Here we investigated FA turnover in a panel of breast cancer models with distinct invasive properties and evaluated the impact of reversine on this turnover in relation to cancer cell invasion in in vitro and in vivo conditions.

Methods:

Live imaging and immunofluorescence assays were used to investigate FA turnover in breast cancer cells. Biochemical studies were used to investigate the impact of reversine on FA signalling and turnover. In vivo activity was investigated using orthotopic breast cancer mouse models.

Results:

Accelerated FA disassembly from plasma membrane protrusions was observed in invasive compared with non-invasive breast cancer cells or non-immortalised mammary epithelial cells. Reversine significantly inhibited FA disassembly leading to stable FAs, which was associated with reduced cell motility and invasion. The inhibitory effect of reversine on FA turnover accounted for a large part on its capacity to interfere with FAK function on regulating its downstream targets. In orthotopic breast cancer mouse models, reversine revealed a potent inhibitory activity on tumour progression to metastasis.

Conclusion:

These results support the utility of targeting FA turnover as a therapeutic approach for invasive breast cancer.     

An increase in cancer stem cell population after primary systemic therapy is a poor prognostic factor in breast cancer

Background:

The cancer stem cell (CSC) hypothesis has important clinical implications for cancer therapeutics because of the proposed role of CSCs in chemoresistance. The aim of this study was to investigate changes in the CSC populations before and after primary systemic therapy (PST) and their prognostic role in human breast cancer.

Methods:

Paired samples (before and after PST) of breast cancer tissue were obtained from clinical stage II or III patients (n=92) undergoing PST with the regimen of doxorubicin plus docetaxel (AD) (n=50) or doxorubicin plus cyclophosphamide (AC) (n=42) and subsequent breast resection. The proportions of putative CSCs with CD44+/CD24− or aldehyde dehydrogenase 1+ (ALDH1+) phenotypes were determined by immunohistochemistry.

Results:

A higher proportion of CD44+/CD24− tumour cells and ALDH1 positivity in pre-chemotherapy tissue was correlated with higher histologic grade, oestrogen receptor (ER) negativity, high Ki-67 proliferation index and basal-like subtype of breast cancer. Aldehyde dehydrogenase 1 positivity in pre-chemotherapy biopsy was also associated with a higher rate of pathologic complete response following PST. In comparisons of putative CSC populations before and after PST, the proportions of CD44+/CD24− and ALDH1+ tumour cells were significantly increased after PST. The cases with increased CD44+/CD24− tumour cell populations after PST showed high Ki-67 proliferation index in post-chemotherapy specimens and those with increased ALDH1+ tumour cell population after PST were associated with ER negativity and p53 overexpression. Furthermore, cases showing such an increase had significantly shorter disease-free survival time than those with no change or a reduced number of CSCs, and the survival difference was most notable with regard to the changes of ALDH1+ tumour cell population in the patients who received AC regimen.

Conclusion:

The present study provides the clinical evidence that the putative CSCs in breast cancer are chemoresistant and are associated with tumour progression, emphasising the need for targeting of CSCs in the breast cancer therapeutics.     

Can shear-wave elastography predict response to neoadjuvant chemotherapy in women with invasive breast cancer?

Background:

Response of invasive breast cancer to neoadjuvant chemotherapy (NAC) is variable, and prediction of response is imperfect. We aimed to ascertain whether tissue stiffness in breast cancers, as assessed by shear-wave elastography (SWE) before treatment, is associated with response.

Methods:

We retrospectively compared pre-treatment tumour mean tissue stiffness, with post-treatment Residual Cancer Burden (RCB) scores and its components in 40 women with breast cancer treated by NAC using Pearson''s correlation coefficient (CC), a general linear model and multiple linear regression. Subgroup analysis was carried out for luminal, HER2-positive and basal immuno-histochemical subtypes.

Results:

Statistically significant correlations were shown between stiffness and RCB scores and between stiffness and percentage tumour cellularity. The correlation between stiffness and percentage cellularity was strongest (CC 0.35 (P<0.0001) compared with CC 0.23 (P=0.004) for the RCB score). The results of a general linear model show that cellularity and RCB score maintain independent relationships with stiffness. By multiple linear regression, only cellularity maintained a significant relationship with stiffness.

Conclusion:

Pre-treatment tumour stiffness measured by SWE, has a statistically significant relationship with pathological response of invasive breast cancer to NAC.     

Disabled-2 downregulation promotes epithelial-to-mesenchymal transition

Background:

Metastatic tumour cells are characterised by acquisition of migratory and invasive properties; properties shared by cells, which have undergone epithelial-to-mesenchymal transition (EMT). Disabled-2 (Dab2) is a putative tumour suppressor whose expression has been shown to be downregulated in various cancer types including breast cancer; however, its exact function in suppressing tumour initiation or progression is unclear.

Methods:

Disabled-2 isoform expression was determined by RT–PCR analysis in human normal and breast tumour samples. Using shRNA-mediated technology, Dab2 was stably downregulated in two cell model systems representing nontumourigenic human mammary epithelial cells. These cells were characterised for expression of EMT markers by RT–PCR and western blot analysis.

Results:

Decreased expression of the p96 and p67 isoforms of Dab2 is observed in human breast tumour samples in comparison to normal human breast tissue. Decreased Dab2 expression in normal mammary epithelial cells leads to the appearance of a constitutive EMT phenotype. Disabled-2 downregulation leads to increased Ras/MAPK signalling, which facilitates the establishment of an autocrine transforming growth factor β (TGFβ) signalling loop, concomitant with increased expression of the TGFβ2 isoform.

Conclusion:

Loss of Dab2 expression, commonly observed in breast cancer, may facilitate TGFβ-stimulated EMT, and therefore increase the propensity for metastasis.     

Ubiquitin D is correlated with colon cancer progression and predicts recurrence for stage II-III disease after curative surgery

Background:

Our recent study observed that the expression of ubiquitin D (UBD), a member of ubiquitin-like modifier family, was upregulated in colon cancer parenchymal cells. The present study further investigated the clinical signicance of UBD in colon cancer.

Methods:

Using quantitative PCR, tissue microarray (TMA), western blot analysis and immunohistochemical stain, we evaluated UBD mRNA and protein levels in tumour tissues from patients with colon cancer at different stages and in paired adjacent normal epithelium.

Results:

Immunohistochemical detection of UBD on a TMA containing 203 paired specimens showed that increased cytoplasmic UBD was signicantly associated with depth of cancer invasion, lymph node metastasis, distant metastasis, tumour histologic grade, advanced clinical stage and Ki-67 proliferative index. Patients with UBD-positive tumours had a significantly higher disease recurrence rate and poorer survival than patients with UBD-negative tumours after the radical surgery. Stratification analysis according to tumour stage revealed UBD as an independent predictor for tumour recurrence in patients with stage II and III tumours.

Conclusion:

UBD may contribute to the progression of colon carcinogenesis and function as a novel prognostic indicator of forecasting recurrence of stage II and III patients after curative operations.     

Elevated expression of myosin X in tumours contributes to breast cancer aggressiveness and metastasis

Background:

Myosin X (MYO10) was recently reported to promote tumour invasion by transporting integrins to filopodial tips in breast cancer. However, the role of MYO10 in tumours remains poorly defined. Here, we report that MYO10 is required in invadopodia to mediate invasive growth and extracellular matrix degradation, which depends on the binding of MYO10''s pleckstrin homology domain to PtdIns(3,4,5)P3.

Methods:

The expression of MYO10 and its associations with clinicopathological and biological factors were examined in breast cancer cells and breast cancer specimens (n=120). Cell migration and invasion were investigated after the silencing of MYO10. The ability of cells to form invadopodia was studied using a fluorescein isothiocyanate-conjugated gelatin degradation assay. A mouse model was established to study tumour invasive growth and metastasis in vivo.

Results:

Elevated MYO10 levels were correlated with oestrogen receptor status, progesterone receptor status, poor differentiation, and lymph node metastasis. Silencing MYO10 reduced cell migration and invasion. Invadopodia were responsible for MYO10''s role in promoting invasion. Furthermore, decreased invasive growth and lung metastasis were observed in the MYO10-silenced nude mouse model.

Conclusions:

Our findings suggest that elevated MYO10 expression increases the aggressiveness of breast cancer; this effect is dependent on the involvement of MYO10 in invadopodial formation.     

Validation of UBE2C protein as a prognostic marker in node-positive breast cancer

Background:

We recently identified and validated UBE2C RNA as a prognostic marker in 252 node-positive (N+) breast cancers by means of a microarray study. The aim of this study was to validate UBE2C protein as a prognostic marker in N+ breast cancer by immunohistochemistry (IHC).

Methods:

To this end, 92 paraffin-embedded blocks were used. The impact of UBE2C IHC value on metastasis-free survival (MFS) and overall survival (OS) was evaluated and compared with Ki-67 and Nottingham prognostic index (NPI) performances.

Results:

In accordance with genomic data, UBE2C IHC had a significant impact both on MFS and OS (hazard ratio=6.79 – P=0.002; hazard ratio=7.14 – P=0.009, respectively). Akaike information criterion proved that the prognostic power of UBE2C IHC was stronger than that of Ki-67 (and close to that of NPI). Furthermore, multivariate analyses with NPI showed that, contrary to Ki-67 IHC, UBE2C IHC remained an independent factor, both for MFS (adjusted P=0.02) and OS (adjusted P=0.04).

Conclusion:

We confirmed that UBE2C protein measured by IHC could be used as a prognostic marker in N+ breast cancer. The potential predictive interest of UBE2C as a marker of proteasome activity needs further investigations.     

Assessment of breast cancer opportunistic screening by clinical�Cpathological indicators: a population-based study

Background:

Although some clinical–pathological features of breast cancers, such as the incidence of ductal cancer in situ (DCIS) and the diameter of invasive tumours, are sensitive indicators of early detection, comprehensive population-based studies of opportunistic screening are needed.

Methods:

Cases of DCIS or invasive breast cancer diagnosed in 1996–2007 were identified from the Ticino Cancer Registry (south of Switzerland). Time trends of age-adjusted incidence and mortality, as well as main clinical–pathological features, such as tumour diameter, AJCC stage and histological grade, were analysed.

Results:

A total of 3047 incident cases of female breast cancer were identified. The proportion of DCIS with respect to invasive cases increased from 5.8% in the period 1996–2001 to 6.4% in the period 2002–2007. The median tumour size of invasive cancers decreased from 20 mm in 1996–2001 to 18 mm in 2002–2007 (P<0.0001). An increase in well/moderately differentiated invasive tumours, from 67% in the period 1996–2001 to 73% in 2002–2007 (P<0.001), was detected and resulted in an Annual Percentage Change of incidence of 2.8 (95% confidence interval: 1.3; 4.3).

Conclusion:

An opportunistic screening strategy can lead to an improvement of prognostic features at diagnosis, but these features are still less favourable than those achieved by organised screening programmes.     

Modified primary tumour/vessel tumour/nodal tumour classification for patients with invasive ductal carcinoma of the breast

Background:

We previously reported that the primary tumour/vessel tumour/nodal tumour (PVN) classification is significantly superior to the UICC pTNM classification and the Nottingham Prognostic Index for accurately predicting the outcome of patients with invasive ductal carcinoma of the breast in a manner that is independent of the nodal status and the hormone receptor status.

Methods:

The purpose of the present study was to compare the outcome predictive power of a modified PVN classification to that of the newly devised pathological UICC pTNM classification and the reclassified Nottingham Prognostic Index in a different group of patients with invasive ductal carcinoma (n=1042) using multivariate analyses by the Cox proportional hazard regression model.

Results:

The modified PVN classification clearly exhibited a superior significant power, compared with the other classifications, for the accurate prediction of tumour recurrence and tumour-related death among patients with invasive ductal carcinoma in a manner that was independent of the nodal status, the hormone receptor status, and adjuvant therapy status.

Conclusion:

The modified PVN classification is a useful classification system for predicting the outcome of invasive ductal carcinoma of the breast.     

Molecular characteristics of screen-detected vs symptomatic breast cancers and their impact on survival

Background:

Several recent studies have shown that screen detection remains an independent prognostic factor after adjusting for disease stage at presentation. This study compares the molecular characteristics of screen-detected with symptomatic breast cancers to identify if differences in tumour biology may explain some of the survival benefit conferred by screen detection.

Methods:

A total of 1379 women (aged 50–70 years) with invasive breast cancer from a large population-based case–control study were included in the analysis. Individual patient data included tumour size, grade, lymph node status, adjuvant therapy, mammographic screening status and mortality. Immunohistochemistry was performed on tumour samples using 11 primary antibodies to define five molecular subtypes. The effect of screen detection compared with symptomatic diagnosis on survival was estimated after adjustment for grade, nodal status, Nottingham Prognostic Index (NPI) and the molecular markers.

Results:

Fifty-six per cent of the survival benefit associated with screen-detected breast cancer was accounted for by a shift in the NPI, a further 3–10% was explained by the biological variables and more than 30% of the effect remained unexplained.

Conclusion:

Currently known biomarkers remain limited in their ability to explain the heterogeneity of breast cancer fully. A more complete understanding of the biological profile of breast tumours will be necessary to assess the true impact of tumour biology on the improvement in survival seen with screen detection.     

Immunological subtypes in breast cancer are prognostic for invasive ductal but not for invasive lobular breast carcinoma

Background:

Classical patient and tumour characteristics are the benchmark of personalised breast cancer (BC) management. Recent evidence has demonstrated that immune and molecular profiling of BC may also play an important role. Despite evidence of differences between invasive ductal (IDC) and lobular (ILC) BC, they are infrequently accounted for when making treatment decisions for individual patients. The purpose of this study was to investigate the relevance of the tumour immune response in the major histological subtypes of BC. We also assessed the relationship between immune responses and molecular subtypes and their prognostic potential.

Methods:

Immunostains were done for HLA-I, HLA-E, HLA-G, Tregs, NK cells and CTLs for the composition of the immune profiles and Ki67, EGFR, CK5/6, ER, PR and HER2 for molecular profiles in 714 breast cancer patients who underwent primary surgery.

Results:

No significant association was found between IDC (90.6%) and ILC (9.4%) and tumour immune subtypes (P=0.4) and molecular subtypes (P=0.4). However, for the relapse-free period (RFP) tumour immune subtyping was prognostic (P=0.002) in IDC, but not ILC. Contrary to ILC, IDC patients frequently expressed higher cleaved caspase-3 and Ki67, which was prognostic. Intermediate immune-susceptible IDC expressing high cleaved caspase-3 or Ki67 showed worse RFP than those with low expression (caspase-3: P=0.004; Ki67: P=0.002); this was not seen for ILC or in high or low immune-susceptible tumour types for either IDC or ILC.

Conclusions:

Tumour immune characteristics and host immune responses are prognostic in IDC, but not ILC. In addition, tumour immune profiles are only prognostic in Luminal A tumours.     

Angiogenesis and lymphangiogenesis are downregulated in primary breast cancer

Background:

Angiogenesis and lymphangiogenesis are considered to play key roles in tumour growth, progression and metastasis. However, targeting tumour angiogenesis in clinical trials showed only modest efficacy. We therefore scrutinised the concept of tumour angiogenesis and lymphangiogenesis by analysing the expression of crucial markers involved in these processes in primary breast cancer.

Methods:

We analysed the expression of angiogenic, lymphangiogenic or antiangiogenic factors, their respective receptors and specific markers for endothelial and lymphendothelial cells by quantitative real-time RT-PCR in primary breast cancer and compared the expression profiles to non-cancerous, tumour-adjacent tissues and breast tissues from healthy women.

Results:

We found decreased mRNA amounts of major angiogenic and lymphangiogenic factors in tumour compared to healthy tissues, whereas antiangiogenic factors were upregulated. Concomitantly, angiogenic and lymphangiogenic receptors were downregulated in breast tumours. This antiangiogenic, antilymphangiogenic microenvironment was even more pronounced in aggressive tumours and accompanied by reduced amounts of endothelial and lymphatic endothelial cell markers.

Conclusion:

Primary breast tumours are not a site of highly active angiogenesis and lymphangiogenesis. Selection for tumour cells that survive with minimal vascular supply may account for this observation in clinical apparent tumours.     

Nuclear osteopontin-c is a prognostic breast cancer marker

Background:

Although Osteopontin has been known as a marker for cancer progression, the elevated production of this cytokine is not specific for cancer. We have identified the splice variant Osteopontin-c as being absent from healthy tissue but associated with about 75% of breast cancer cases. However, in previous studies of Osteopontin-c, follow-up information was not available.

Methods:

Here we have analysed 671 patients, comprising a cohort of 291 paraffin blocks plus a population-based case-control study of 380 arrayed breast tumor tissues.

Results:

We find that high staining intensity of nuclear Osteopontin-c is strongly associated with mortality in patients with early breast cancer. Cytosolic staining for exon 4, reflective of Osteopontin-a and -b also predicts poor outcome. By contrast, total Osteopontin does not correlate with prognosis. These diverse assessments of Osteopontin also do not correlate with each other, suggesting distinct expression patterns for the variant forms. Consistent with its role in tumor progression, not tumor initiation, Osteopontin-c is not correlated with proliferation markers (Ki-67, cyclin A, cyclin B, cyclin E and cyclin D), neither is it correlated with ER, PR or HER2.

Conclusions:

The addition of Osteopontin-c immunohistochemistry to standard pathology work-ups may have prognostic benefit in early breast cancer diagnosis.     

Measuring the biological effect of presurgical metformin treatment in endometrial cancer

Background:

Preclinical studies in endometrial cancer (EC) show that metformin reduces cellular proliferation by PI3K-AKT-mTOR inhibition. We tested the hypothesis that short-term presurgical metformin reduces cellular proliferation in atypical endometrial hyperplasia (AEH) and endometrioid EC, and assessed the feasibility of using phosphorylated PI3K-AKT-mTOR proteins as tissue end points.

Methods:

Women with AEH or EC received metformin 850 mg twice a day or no drug in the presurgical window between diagnosis and hysterectomy. Before and after the window, tissue samples were obtained; serum markers of insulin resistance (e.g. homeostasis model of assessment of insulin resistance index) were determined; and anthropometrics measured (e.g. BMI). Cell proliferation (Ki-67) and PI3K-AKT-mTOR phosphostatus were assessed by immunohistochemistry and scored blinded to treatment.

Results:

Twenty-eight metformin-treated and 12 untreated patients, well matched for age and BMI, completed the study. Metformin treatment (median 20 days, range 7–34) was associated with a 17.2% reduction in tumour Ki-67 (95% CI −27.4, −7.0, P=0.002), in a dose-dependent manner. Tumour PI3K-AKT-mTOR protein phosphostatus varied but the effects were not significant after adjusting for changes in controls.

Conclusions:

Short-term metformin was associated with reduced Ki-67 expression in EC. Changes in tumour PI3K-AKT-mTOR protein phosphostatus were seen in both groups. Future studies should address the variability attributed to different sampling techniques including devascularisation of the uterus at hysterectomy.