Correlation of BRAF and NRAS mutation status with outcome, site of distant metastasis and response to chemotherapy in metastatic melanoma.

BACKGROUND: The prognostic significance of BRAF and NRAS mutations in metastatic melanoma patients remains uncertain, with several studies reporting conflicting results, often biased by the inclusion of patients treated with BRAF and MEK (MAPK) inhibitors. We therefore interrogated a historical cohort of patients free of the confounding influence of MAPK inhibitor therapy. METHODS: Patients with available archival tissue first diagnosed with metastatic melanoma between 2002 and 2006 were analysed. Mutational analysis was performed using the OncoCarta Panel. Patient characteristics, treatment outcome and survival were correlated with BRAF/NRAS mutation status. RESULTS: In 193 patients, 92 (48%) melanomas were BRAF-mutant, 39 (20%) were NRAS-mutant and 62 (32%) were wild-type for BRAF/NRAS mutations (wt). There was no difference in response to chemotherapy based on mutation status (35-37%). The distant disease-free interval (DDFI) was significantly shorter in patients with wt melanoma (27.9 months vs 35.1 for BRAF and 49.1 for NRAS) although this was not significant in multivariate analysis. Survival from stage IV melanoma diagnosis was not significantly different based on mutation status. The DDFI was significantly shorter in patients with BRAF(V600K/R) versus BRAF(V600E) melanoma in univariate and multivariate analyses. CONCLUSIONS: BRAF and NRAS mutation status does not influence survival in metastatic melanoma.

CTC-5: A novel digital pathology approach to characterise circulating tumour cell biodiversity.

Metastatic progression and tumor evolution complicates the clinical management of cancer patients. Circulating tumor cell (CTC) characterization is a growing discipline that aims to elucidate tumor metastasis and evolution processes. CTCs offer the clinical potential to monitor cancer patients for therapy response, disease relapse, and screen 'at risk' groups for the onset of malignancy. However, such clinical utility is currently limited to breast, prostate, and colorectal cancer patients. Further understanding of the basic CTC biology of other malignancies is required to progress them towards clinical utility. Unfortunately, such basic clinical research is often limited by restrictive characterization methods and high-cost barrier to entry for CTC isolation and imaging infrastructure. As experimental clinical results on applications of CTC are accumulating, it is becoming clear that a two-tier system of CTC isolation and characterization is required. The first tier is to facilitate basic research into CTC characterization. This basic research then informs a second tier specialised in clinical prognostic and diagnostic testing. This study presented in this manuscript describes the development and application of a low-cost, CTC isolation and characterization pipeline; CTC-5. This approach uses an established 'isolation by size' approach (ScreenCell Cyto) and combines histochemical morphology stains and multiparametric immunofluorescence on the same isolated CTCs. This enables capture and characterization of CTCs independent of biomarker-based pre-selection and accommodates both single CTCs and clusters of CTCs. Additionally, the developed open-source software is provided to facilitate the synchronization of microscopy data from multiple sources (https://github.com/CTC5/). This enables high parameter histochemical and immunofluorescent analysis of CTCs with existing microscopy infrastructure without investment in CTC specific imaging hardware. Our approach confirmed by the number of successful tests represents a potential major advance towards highly accessible low-cost technology aiming at the basic research tier of CTC isolation and characterization. The biomarker independent approach facilitates closing the gap between malignancies with poorly, and well-defined CTC phenotypes. As is currently the case for some of the most commonly occurring breast, prostate and colorectal cancers, such advances will ultimately benefit the patient, as early detection of relapse or onset of malignancy strongly correlates with their prognosis.

Prediction of outcome of early ER+ breast cancer is improved using a biomarker panel, which includes Ki-67 and p53.

BACKGROUND: The aim of this study is to determine whether immunohistochemical (IHC) assessment of Ki67 and p53 improves prognostication of oestrogen receptor-positive (ER+) breast cancer after breast-conserving therapy (BCT). In all, 498 patients with invasive breast cancer from a randomised trial of BCT with or without tumour bed radiation boost were assessed using IHC. METHODS: The ER+ tumours were classified as 'luminal A' (LA): ER+ and/or PR+, Ki-67 low, p53-, HER2- or 'luminal B' (LB): ER+ and/or PR+and/or Ki-67 high and/or p53+ and/or HER2+. Kaplan-Meier and Cox proportional hazards methodology were used to ascertain relationships to ispilateral breast tumour recurrence (IBTR), locoregional recurrence (LRR), distant metastasis-free survival (DMFS) and breast cancer-specific survival (BCSS). RESULTS: In all, 73 patients previously LA were re-classified as LB: a greater than four-fold increase (4.6-19.3%) compared with ER, PR, HER2 alone. In multivariate analysis, the LB signature independently predicted LRR (hazard ratio (HR) 3.612, 95% CI 1.555-8.340, P=0.003), DMFS (HR 3.023, 95% CI 1.501-6.087, P=0.002) and BCSS (HR 3.617, 95% CI 1.629-8.031, P=0.002) but not IBTR. CONCLUSION: The prognostic evaluation of ER+ breast cancer is improved using a marker panel, which includes Ki-67 and p53. This may help better define a group of poor prognosis ER+ patients with a greater probability of failure with endocrine therapy.

Extended thromboprophylaxis post gynaecological cancer surgery; the effect of weight adjusted and fixed dose LMWH (Tinzaparin).

OBJECTIVE: Gynaecological cancer surgery is associated with high rates of venous thromboembolism (VTE) despite recommended prophylaxis. We sought to investigate the impact of extended prophylaxis with fixed dose and weight based LMWH in patients undergoing gynaecological cancer surgery. METHODS: VTE rates were recorded in patients who received LMWH prophylaxis (4500 IU Tinzaparin once daily) for the duration of hospital stay (2006-2012) (n = 610) and were compared with VTE rates in patients who underwent surgery after the introduction of extended prophylaxis (3500/4500 IU Tinzaparin for patients with BMI < 40kg/m2 and 75 IU/kg for BMI > 40 kg/m2) (2012-2017) (n = 651). Peak (4 h) anti-Xa levels in a subset of patients were also evaluated. RESULTS: 73 (5.7%) cases of VTE were recorded during 1 year of follow-up. 20 cases occurred during hospital stay. There was no significant difference in the rate of VTE between the extended prophylaxis cohort and the standard prophylaxis cohort. 23/24 patients who developed VTE in the extended prophylaxis cohort received a fixed (4500 units) dose of Tinzaparin. 63% of patients who received a fixed LMWH dose had peak anti-Xa levels below the target range (0.2-0.4 IU/ml). Peak anti-Xa was lower in patients who subsequently developed VTE compared with those who received either fixed dose (P = 0.041) and weight adjusted Tinzaparin (P = 0.0006). CONCLUSIONS: Extended prophylaxis with Tinzaparin does not significantly reduce VTE rates in gynaecological cancer patients post surgery. Peak anti-Xa levels may be suboptimal in many patients receiving a fixed LMWH dose. Further studies are required to determine whether weight adjusted doses of Tinzaparin may provide more effective prophylaxis following gynaecological cancer surgery.

BAG-1 predicts patient outcome and tamoxifen responsiveness in ER-positive invasive ductal carcinoma of the breast.

BAG-1 (bcl-2-associated athanogene) enhances oestrogen receptor (ER) function and may influence outcome and response to endocrine therapy in breast cancer. We determined relationships between BAG-1 expression, molecular phenotype, response to tamoxifen therapy and outcome in a cohort of breast cancer patients and its influence on tamoxifen sensitivity in MCF-7 breast cancer cells in vitro. Publically available gene expression data sets were analysed to identify relationships between BAG-1 mRNA expression and patient outcome. BAG-1 protein expression was assessed using immunohistochemistry in 292 patients with invasive ductal carcinoma and correlated with clinicopathological variables, therapeutic response and disease outcome. BAG-1-overexpressing MCF-7 cells were treated with antioestrogens to assess its effects on cell proliferation. Gene expression data demonstrated a consistent association between high BAG-1 mRNA and improved survival. In ER+ cancer (n=189), a high nuclear BAG-1 expression independently predicted improved outcome for local recurrence (P=0.0464), distant metastases (P=0.0435), death from breast cancer (P=0.009, hazards ratio 0.29, 95% CI: 0.114-0.735) and improved outcome in tamoxifen-treated patients (n=107; P=0.0191). BAG-1 overexpression in MCF-7 cells augmented antioestrogen-induced growth arrest. A high BAG-1 expression predicts improved patient outcome in ER+ breast carcinoma. This may reflect both a better definition of the hormone-responsive phenotype and a concurrent increased sensitivity to tamoxifen.

The key hypoxia regulated gene CAIX is upregulated in basal-like breast tumours and is associated with resistance to chemotherapy.

Basal-like tumours account for 15% of invasive breast carcinomas and are associated with a poorer prognosis and resistance to therapy. We hypothesised that this aggressive phenotype is because of an intrinsically elevated hypoxic response. Microarrayed tumours from 188 patients were stained for hypoxia-inducible factor (HIF)-1alpha, prolyl hydroxylase (PHD)1, PHD2, PHD3 and factor inhibiting HIF (FIH)-1, and carbonic anhydrase (CA) IX stained in 456 breast tumours. Tumour subtypes were correlated with standard clincopathological parameters as well as hypoxic markers. Out of 456 tumours 62 (14%) tumours were basal-like. These tumours were positively correlated with high tumour grade (P<0.001) and were associated with a significantly worse disease-free survival compared with luminal tumours (P<0.001). Fifty percent of basal-like tumours expressed HIF-1alpha, and more than half expressed at least one of the PHD enzymes and FIH-1. Basal-like tumours were nine times more likely to be associated with CAIX expression (P<0.001) in a multivariate analysis. Carbonic anhydrase IX expression was positively correlated with tumour size (P=0.005), tumour grade (P<0.001) and oestrogen receptor (ER) negativity (P<0.001). Patients with any CAIX-positive breast tumour phenotype and in the basal tumour group had a significantly worse prognosis than CAIX-negative tumours when treated with chemotherapy (P<0.001 and P=0.03, respectively). The association between basal phenotype and CAIX suggests that the more aggressive behaviour of these tumours is partly due to an enhanced hypoxic response. Further, the association with chemoresistance in CAIX-positive breast tumours and basal-like tumours in particular raises the possibility that targeted therapy against HIF pathway or downstream genes such as CAs may be an approach to investigate for these patients.

OC-12 - Peri operative venous thromboembolism prophylaxis in gynaecological cancer patients. A survey of current practice.

INTRODUCTION: Gynaecological cancer is associated with some of the highest rates of venous thromboembolism (VTE) with some subtypes of ovarian cancer associated with rates as high as 20%. VTE prophylaxis is an important part of post-operative management in gynaecological cancer patient care. Despite the evidence base and guidelines recommending extended VTE prophylaxis for patients undergoing major cancer surgery, adherence to best practice guidelines has been found to be low. AIM: The aim of this study is to assess gynaecological oncologist's awareness of the guidelines surrounding VTE prophylaxis for post-operative gynaecological cancer patients and to determine the type and duration of VTE prophylaxis implemented by gynaecological oncologists. MATERIALS AND METHODS: The study used the European Society Gynaecology Oncology (ESGO) membership as the population studied. ESGO is a multidisciplinary, non-profit association, founded in 1983. ESGO consisit of more than 1800 professional of different specialities dealing with gynaecological oncology. The e mail address of 650 member were avilable on the ESGO website. We send a Survey Monkey link to the questionnaire by email to a total of 650 ESGO member whose email addresses were obtained from the ESGO directory. 205 e mails returned back as the email used was invalied, only 445 e mail successfully delivered. The survey remained open for 44 days. Results were analysed on Survey Monkey. RESULTS: A 59.3% of respondents said that they decided upon appropriate VTE prophylaxis for a patient according to national/international best practice guidelines. A further 39.4% respondents said that they made their choice based upon clinical judgement. 59.8% of respondents said that they begin VTE prophylaxis pre-operatively for the high risk patients. 6.1% said that they begin prophylaxis in the operating theatre, 18.9% begin prophylaxis 6 hours post-operatively and 9.1% begin prophylaxis 12 hours post-operatively. The remaining respondents said that they begin VTE more than 24 hours post operatively 44.7% said that they prescribe VTE prophylaxis for 4 weeks. A further 15.9% said that they prescribe VTE prophylaxis for 6 weeks and 4.75% for longer than 6 weeks. CONCLUSIONS: In conclusion, the adherence to current guidelines for VTE prophylaxis in the peri-operative period for gynaecological oncology patients is still poor. Awareness needs to be raised in order to decrease the morbidity/mortality of VTE in this high risk group of patients. The adoption of multidiscplinary approach to manage gynaecological cancer patients, which includes the involvment of thrombosis specialist, may reduce post operative VTE rates and improve cancer care.

PO-24 - Determinants of thrombin generation in gynaecological malignancies.

INTRODUCTION: Increased thrombin production is associated with malignancy and is a marker for venous thromboembolism (VTE). Our group has shown that thrombin generation is increased in gynaecological malignancies. Although tumour derived Tissue Factor (TF) has been implicated, the precise mechanism by which thrombin production is increased is not fully understood. Our group has shown that gynaecological cancers can alter tumour expression of cogulation proteases. These changes may be implicated in the increased thrombin generation observed. Previous studies in normal control patients by other groups have shown that multiple coagulation factors are implicated in thrombin generation and that the effects depend on assay conditions however free Tissue Factor Pathway Inhibitor (TFPI), Factors V, VIIIc and protein S, were significant determinants of thrombin generation. AIM: The aim of this study was to determine the effect of factor V factor, VIIIc, TFPI and free protein S on the thrombin generation in patients with endometrial and ovarian cancer compared with benign controls. MATERIALS AND METHODS: Patients with a gynaecological malignancy (n=43) (ovarian or endometrial) were matched with patients with a benign tumour (n=43) gave full and informed consent. Venous blood samples were obtained prior to surgery and chemotherapy. Thrombin generation was was measured using a fluorogenic assay. Lag time, peak thrombin and area under the thrombin generation curve (ETP) was determined and reported for each sample. Free protein S, free TFPI and factor V were determined using ELISA. Factor VIIIc was determined using a hromogenic assay. RESULTS: Factor V and factor VIIIc were significantly increased in the malignant group compared with the benign group (P<0.03; P<0.006). Increased free TFPI levels were also observed in the malignant group but this did not reach significance (P<0.06). There was no difference in free Protein S levels between the groups. Highest levels of peak thrombin generation were observed in the high grade serous and clear cell ovarian cancer patients. Changes were less marked in the endometrial patients. Free TFPI, factor V and factor VIIIc were important determinants of thrombin generation in the malignant group. CONCLUSIONS: Coagulation factors V and VIIIc and free TFPI are altered in patients with gynaecological malignancies and contribute to the increased thrombin generation found in these cancer patients. We have previously found increased expression of factor V in tumours from patients with ovarian cancer in addition to increased TF expression. These changes may explain the high rate of venous thromboembolism found in these patients.

PO-14 - Tumour expression of coagulation proteases of the aPC pathway - a role in the pathogenesis of gynaecological cancers?

INTRODUCTION: The close relationship between coagulation, thrombosis and cancer has long been established. Gynaecological cancers, in particular ovarian cancers, carry a high risk of thrombosis but coagulation activation is also thought to play a role in tumorigenesis and metastasis. In experimental animal models of metastasis, mice with a genetic procoagulant phenotype are prone to develop metastasis and anticoagulant therapy dramatically reduces pulmonary metastasis in these models. The aPC pathway is a key natural anticoagulant pathway, in addition to its role in venous thrombosis, dysregulation of this pathway is also thought to play a role in the pathogenesis of some cancers. No data exists in ovarian and endometrial cancers. AIM: The aim of this study is to determine the expression of key proteins of the activated protein C pathway in endometrial and ovarian malignant tumours compared to benign tumours and to assess their role in patient survival. MATERIALS AND METHODS: RNA was extracted from 78 (54 malignant and 24 benign) fresh frozen ovarian and endometrial tumours samples. Tumour biopsies were mRNA expression of endothelial protein C receptor (EPCR), protein S (PS), protein C (PC), thrombomodulin (TM), Factor V (FV) and VIII (FVIII) and PAR-1 and PAR-2 was measured using TaqMan Low Density Arrays. mRNA fold change relative to benign expression was determined using the 2 -delta delta Ct method with 18s as internal standard. All patients gave full and informed consent and the study had the approval of the hospital ethics committee. Total cell protein was extracted from ovarian tumour tissue. Enzyme-linked immunosorbent assay (ELISA) was used to measure protein plasma expression RESULTS: EPCR (P<0.001), protein S (P<0.0001) and Factor VIII (P<0.003) mRNA expression was significantly downregulated in malignant tumours compared with benign. Factor V and PAR-2 were significantly upregulated (P<0.001; P<0.004). Protein C was not consistently expressed. Reduced EPCR and TM protein expression was also observed in malignant tumours with increased plasma levels of Factor V. Reduced protein S and increased FV were associated with decreased survival. Plasma levels of Factor V were related to grade in the endometrial cancer group. PAR-2 mRNA expression was increased in ovarian tumours (P<0.001) however PAR-1 expression remained unchanged. CONCLUSIONS: Our results show reduced expression of key proteins associated with activation of protein C combined with increased expression in FV in gynaecological malignancies. These changes may contribute to local thrombin production and tumour progression and metastasis. Further work is required to determine the precise mechanisms involved.

ASCT2/SLC1A5 controls glutamine uptake and tumour growth in triple-negative basal-like breast cancer.

Alanine, serine, cysteine-preferring transporter 2 (ASCT2; SLC1A5) mediates uptake of glutamine, a conditionally essential amino acid in rapidly proliferating tumour cells. Uptake of glutamine and subsequent glutaminolysis is critical for activation of the mTORC1 nutrient-sensing pathway, which regulates cell growth and protein translation in cancer cells. This is of particular interest in breast cancer, as glutamine dependence is increased in high-risk breast cancer subtypes. Pharmacological inhibitors of ASCT2-mediated transport significantly reduced glutamine uptake in human breast cancer cell lines, leading to the suppression of mTORC1 signalling, cell growth and cell cycle progression. Notably, these effects were subtype-dependent, with ASCT2 transport critical only for triple-negative (TN) basal-like breast cancer cell growth compared with minimal effects in luminal breast cancer cells. Both stable and inducible shRNA-mediated ASCT2 knockdown confirmed that inhibiting ASCT2 function was sufficient to prevent cellular proliferation and induce rapid cell death in TN basal-like breast cancer cells, but not in luminal cells. Using a bioluminescent orthotopic xenograft mouse model, ASCT2 expression was then shown to be necessary for both successful engraftment and growth of HCC1806 TN breast cancer cells in vivo. Lower tumoral expression of ASCT2 conferred a significant survival advantage in xenografted mice. These responses remained intact in primary breast cancers, where gene expression analysis showed high expression of ASCT2 and glutamine metabolism-related genes, including GLUL and GLS, in a cohort of 90 TN breast cancer patients, as well as correlations with the transcriptional regulators, MYC and ATF4. This study provides preclinical evidence for the feasibility of novel therapies exploiting ASCT2 transporter activity in breast cancer, particularly in the high-risk basal-like subgroup of TN breast cancer where there is not only high expression of ASCT2, but also a marked reliance on its activity for sustained cellular proliferation.

Procoagulant activity in gynaecological cancer patients; the effect of surgery and chemotherapy.

BACKGROUND: Gynaecological cancers are associated with high rates of venous thromboembolism (VTE). Studies on ambulatory cancer patients do not support thromboprophylaxis during chemotherapy. Approximately 6-7% of gynaecological cancer patients suffer a postoperative VTE despite Low Molecular Weight Heparin prophylaxis (LMWH). Large cancer studies have shown that Calibrated Automated Thrombogram (CAT) and Microparticles (MP) assays may be useful in predicting VTE but data on gynaecological cancer patients is scarce. OBJECTIVE: Our objective was to identify whether the CAT assay and MP functional assays have potential as biomarkers predictive of VTE in gynaecological cancer patients. PATIENTS AND METHODS: Gynaecological cancer patients were investigated before surgery (n=146) and at 5, 14 and 42days post-surgery (n=78). Fourteen additional patients were investigated before chemotherapy and after 3 and 6 cycles of therapy. Thrombin generation was measured before and after addition of thrombomodulin. RESULTS: Patients with clear cell cancer (CCC) of the ovary and patients with endometrial cancer had higher ETP and peak thrombin compared with patients with benign disease. Patients who developed VTE (n=8) following surgery had enhanced thrombin generation prior to surgery which persisted during the post-operative period despite LMWH prophylaxis. Both neoadjuvant and adjuvant chemotherapy showed increased thrombin generation following addition of thrombomodulin. There were no differences in MP levels during the study. CONCLUSIONS: CAT assay shows potential as a promising biomarker for the prediction of VTE in gynaecological cancer patients. The identification of high risk patients combined with individualised LMWH prophylaxis might reduce VTE in this high risk group.

Alterations of insulin-like growth factor-1 receptor gene copy number and protein expression are common in non-small cell lung cancer.

AIMS: Insulin-like growth factor-1 receptor (IGF1R) is a tyrosine kinase membrane receptor involved in tumourigenesis that may be a potential therapeutic target. We aimed to investigate the incidence and prognostic significance of alterations in IGF1R copy number, and IGF1R protein expression in resected primary non-small cell lung cancer (NSCLC), and lymph node metastases. METHODS: IGF1R gene copy number status was evaluated by chromogenic silver in situ hybridisation and IGF1R protein expression was evaluated by immunohistochemistry in tissue microarray sections from a retrospective cohort of 309 surgically resected NSCLCs and results were compared with clinicopathological features, including EGFR and KRAS mutational status and patient survival. RESULTS: IGF1R gene copy number status was positive (high polysomy or amplification) in 29.2% of NSCLC, and 12.1% exhibited IGF1R gene amplification. High IGF1R expression was found in 28.3%. There was a modest correlation between IGF1R gene copy number and protein expression (r=0.2, p<0.05). Alterations of IGF1R gene copy number and protein expression in primary tumours were significantly associated with alterations in lymph node metastases (p<0.01). High IGF1R gene copy number and protein expression was significantly higher in squamous cell carcinomas (SCC) compared with other subtypes of NSCLC (p<0.05). There were no other associations between IGF1R status and other clinicopathological features including patient age, gender, smoking status, tumour size, stage, grade, EGFR or KRAS mutational status or overall survival. CONCLUSIONS: High IGF1R gene copy number and protein overexpression are frequent in NSCLC, particularly in SCCs, but they are not prognostically relevant.

c-Myc and Her2 cooperate to drive a stem-like phenotype with poor prognosis in breast cancer.

The HER2 (ERBB2) and MYC genes are commonly amplified in breast cancer, yet little is known about their molecular and clinical interaction. Using a novel chimeric mammary transgenic approach and in vitro models, we demonstrate markedly increased self-renewal and tumour-propagating capability of cells transformed with Her2 and c-Myc. Coexpression of both oncoproteins in cultured cells led to the activation of a c-Myc transcriptional signature and acquisition of a self-renewing phenotype independent of an epithelial-mesenchymal transition programme or regulation of conventional cancer stem cell markers. Instead, Her2 and c-Myc cooperated to induce the expression of lipoprotein lipase, which was required for proliferation and self-renewal in vitro. HER2 and MYC were frequently coamplified in breast cancer, associated with aggressive clinical behaviour and poor outcome. Lastly, we show that in HER2(+) breast cancer patients receiving adjuvant chemotherapy (but not targeted anti-Her2 therapy), MYC amplification is associated with a poor outcome. These findings demonstrate the importance of molecular and cellular context in oncogenic transformation and acquisition of a malignant stem-like phenotype and have diagnostic and therapeutic consequences for the clinical management of HER2(+) breast cancer.

EGFR mutant-specific immunohistochemistry has high specificity and sensitivity for detecting targeted activating EGFR mutations in lung adenocarcinoma.

AIM: We assessed the diagnostic accuracy of epidermal growth factor receptor (EGFR) mutant-specific antibodies for detecting two common activating EGFR mutations. METHODS: Immunohistochemical expression of mutation-specific antibodies against EGFR exon 19 deletion E746-A750 ((c.2235_2249del15 or c.2236_2250del15, p. Glu746_Ala750del) and exon 21 L858R point mutation (c.2573T>G, p.Leu858Arg) were assessed in a cohort of 204 resected early stage node negative lung adenocarcinomas, and protein expression was compared with DNA analysis results from mass spectrometry analysis. RESULTS: Of seven cases with L858R point mutation, six were positive by immunohistochemistry (IHC). There were three false positive cases using L858R IHC (sensitivity 85.7%, specificity 98.5%, positive predictive value 66.7%, negative predictive value 99.5%). All seven E746-A750 exon 19 deletions identified by mutation analysis were positive by IHC. Four additional cases were positive for exon 19 IHC but negative by mutation analysis. The sensitivity of exon 19 IHC for E746-A750 was 100%, specificity 98.0%, positive predictive value 63.6% and negative predictive value 100%. CONCLUSIONS: Mutant-specific EGFR IHC has good specificity and sensitivity for identifying targeted activating EGFR mutations. Although inferior to molecular genetic analysis of the EGFR gene, IHC is highly specific and sensitive for the targeted EGFR mutations. The antibodies are likely to be of clinical value in cases where limited tumour material is available, or in situations where molecular genetic analysis is not readily available.

Identification of PUMA as an estrogen target gene that mediates the apoptotic response to tamoxifen in human breast cancer cells and predicts patient outcome and tamoxifen responsiveness in breast cancer.

Recognition of the pivotal role of estrogen in the aetiology of breast cancer has led to the development of antiestrogens (AE), such as tamoxifen (TAM) as effective therapies for the treatment and prevention of this disease. However, despite their widespread clinical efficacy, response to AEs is often short-lived, and acquired or innate therapeutic resistance remains a major obstacle in the successful treatment of breast cancer. Thus, delineating the intracellular pathways that mediate the cellular response to estrogen could potentially lead to new, more effective approaches to the treatment of breast cancer, particularly endocrine-resistant disease. Here, we have identified the BCL-2 homology 3 (BH3)-only, pro-apoptotic regulator, PUMA (p53 upregulated modulator of apoptosis) as an estrogen target gene that is acutely downregulated in response to estrogen in breast cancer cell lines, independently of their p53 status. PUMA is transcriptionally upregulated following treatment with TAM, and knock down of PUMA expression in these cells attenuates the apoptotic response to TAM. Furthermore, low PUMA expression in breast carcinomas is significantly associated with breast cancer-specific death (P=0.0014 and P=0.0115, for mRNA and protein, respectively), and worse outcome in TAM-treated patients (mRNA, P=1.49e-05). These findings suggest that the dysregulation of apoptotic signaling pathways such as those executed through PUMA, can significantly impact on both the progression and therapeutic responsiveness of breast cancer. Moreover, they provide a convincing rationale for exploring new therapeutic approaches involving endocrine and non-endocrine therapies that target apoptotic pathways as an effective strategy for tackling endocrine refractory disease.

Cyclin D1b protein expression in breast cancer is independent of cyclin D1a and associated with poor disease outcome.

Aberrant expression of cyclin D1 protein is a common feature of breast cancer. However, the CCND1 gene encodes two gene products, cyclin D1a and cyclin D1b, which have discrete mechanisms of regulation and impact on cell behavior. A polymorphism at nucleotide 870 in the CCND1 gene, rs603965, influences the relative production of the encoded proteins and can impart increased risk for tumor development. Here, the impact of both the G/A870 polymorphism and cyclin D1b protein production on breast cancer risk, disease phenotype and patient outcome was analysed. In a large multiethnic case-control study, the G/A870 polymorphism conferred no significant risk for breast cancer overall or by stage or estrogen receptor (ER) status. However, the cyclin D1b protein was found to be upregulated in breast cancer, independent of cyclin D1a levels, and exhibited heterogeneous levels in breast cancer specimens. High cyclin D1a expression inversely correlated with the Ki67 proliferation marker and was not associated with clinical outcome. In contrast, elevated cyclin D1b expression was independently associated with adverse outcomes, including recurrence, distant metastasis and decreased survival. Interestingly, cyclin D1b was particularly associated with poor outcome in the context of ER-negative breast cancer. Thus, specific cyclin D1 isoforms are associated with discrete forms of breast cancer and high cyclin D1b protein levels hold prognostic potential.

Potential predictors of chemotherapy response in ovarian cancer--how do we define chemosensitivity?

OBJECTIVE: The aim of this study was to assess whether microvessel density (measured by CD31), vascular endothelial growth factor (VEGF) or multidrug resistance (MDR1) could determine the response to chemotherapy or act as prognostic factors in ovarian cancer. METHODS: Seventy-nine ovarian specimens were immunostained. Pearson correlation, 1-way ANOVA and chi-square were used for univariate analysis. Kaplan Meier survival curves were used, log-rank was used for univariate analysis and a Cox proportional hazards regression model was used for multivariate evaluation. Response to chemotherapy was assessed after 6 months and again after 1 year. RESULT: Quantifying VEGF proved to be a valuable independent prognostic indicator in progression-free survival (PFS) (p<0.05) and overall survival (OS) (p<0.0001). VEGF correlated with response to chemotherapy at the 6-month interval (r=0.446, p<0.001) but failed to correlate at the 1-year interval. Increased staining with CD31 was associated with decreased PFS (p<0.01) and OS (p<0.01) in univariate but not multivariate analysis. MDR1 failed to act as a prognostic marker or as a predictor of response to chemotherapy. CONCLUSION: VEGF correlates with response to chemotherapy at the 6-month but not the 12-month interval. What should our criteria be for determining sensitivity to chemotherapy? CD31, VEGF and MDR1 do play a role in some ovarian malignancies but other factors are likely to be involved and perhaps molecular profiling will determine which factors will be important for determining the response to chemotherapy.

Genome-wide analysis of deoxyribonucleic acid in endometrial cancer using comparative genomic hybridization microarrays.

The aim of this study was to identify amplified oncogenes in endometrial cancer using array-based comparative genomic hybridization (array CGH). Despite its prevalence, the molecular mechanisms of endometrial carcinogenesis are still poorly understood. The selected array CGH allows the simultaneous examination of 58 oncogenes commonly amplified in human cancers and is capable of achieving increased mapping resolution compared with conventional CGH. A subset of 8 specimens from a bank of 60 malignant and normal specimens was selected for array analysis to identify potential genes of interest. TaqMan polymerase chain reaction was carried out on the 60 specimens to examine if aberrations at the genomic level correlated with gene expression and to compare expression in normal and malignant samples. Oncogenes amplified in the endometrial cancers included AR, PIK3CA, MET, HRAS, NRAS, D17S1670, FGFR1, CTSB, RPS6KB1, LAMC2, MYC, PDGFRA, FGF4/FGF3, PAKI, and FGR. Three genes were examined at the messenger RNA level. AR and PIK3CA were higher in normal specimens, and MET was higher in malignant samples, suggesting a role for MET in endometrial cancer. Newer arrays examining more genes and larger sample numbers are necessary to elucidate the carcinogenic pathway in endometrial cancer.

Serous papillary adenocarcinomas of the ovary display heterogeneity in their response to chemotherapy.

The response of ovarian serous papillary adenocarcinomas to various cytotoxic drugs was examined using the (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium, inner salt) (MTS) cytotoxicity assay. Thirty tumors were collected and organized into four groups according to histologic grade and FIGO stage: stage III, grade 2; stage III, grade 3; stage IV, grade 2; and stage IV, grade 3. The MTS chemosensitivity assay was performed on each tumor to examine the response to cisplatin, paclitaxel, hycamtin and the combination of cisplatin and paclitaxel. Ovarian adenocarcinomas of similar stage and grade displayed varying responses to the same drug. A lower concentration of the drug was often as effective as the peak plasma concentration. For some specimens combination therapy was more effective for inhibiting tumor growth, and for others single-agent therapy gave a better response. A chemosensitivity/resistance profile is recommended before deciding on appropriate chemotherapy.