WHO 2022 classification of penile and scrotal cancers: updates and evolution

Squamous cell carcinoma (SCC) is the most common malignant tumour of the penis. The 2022 WHO classification reinforces the 2016 classification and subclassifies precursor lesions and tumours into human papillomavirus (HPV)-associated and HPV-independent types. HPV-associated penile intraepithelial neoplasia (PeIN) is a precursor lesion of invasive HPV- associated SCC, whereas differentiated PeIN is a precursor lesion of HPV-independent SCC. Block-type positivity of p16 immunohistochemistry is the most practical daily utilised method to separate HPVassociated from HPVindependent penile SCC. If this is not feasible, the term SCC, not otherwise specified (NOS) is appropriate. Certain histologies that were previously classified as "subtypes" are now grouped, and coalesced as "patterns", under the rubric of usual type SCC and verrucous carcinoma (e.g. usual-type SCC includes pseudohyperplastic and acantholytic/pseudoglandular carcinoma, and carcinoma cuniculatum is included as a pattern of verrucous carcinoma). If there is an additional component of the usual type of invasive SCC (formerly termed hybrid histology), the tumour would be a mixed carcinoma (e.g. carcinoma cuniculatum or verrucous carcinoma with usual invasive SCC); in such cases, reporting of the relative percentages in mixed tumours may be useful. The consistent use of uniform nomenclature and reporting of percentages will inform the refinement of future reporting classification schemes and guidelines/recommendations. The classification of scrotal tumours is provided for the first time in the fifth edition of the WHO Blue book, and it follows the schema of penile cancer classification for both precursor lesions and the common SCC of the scrotum. Basal cell carcinoma of the scrotum may have a variable clinical course and finds a separate mention.

Abstract P4-08-17: Expression score (Escore) for the prediction of likelihood of recurrence of DCIS

Background: Ductal carcinoma in situ (DCIS) accounts for at least 20% of breast cancers. Factors associated with recurrence of DCIS or progression to invasive carcinoma are not well delineated. The goals of the current study were to profile the epithelial cells using the GE Cell DIVE™ immuno-fluorescent based analyses. This was coupled with semi-automated algorithms to characterize the inter-relationships between cell populations and likelihood of recurrence.

Patients and Methods: A TMA-based (total 8 TMAs) cohort of cases of DCIS with and without recurrence was obtained from Oxford University. Recurrence in this cohort was defined as ipsilateral DCIS, ipsilateral invasive, contralateral invasive and metastatic. Analysis for 31 epithelial markers (HER4, CK56, ABCG2, PTEN, S6, CKAE1, PR, ER, NaKATPase, CK19, ALDH1, CK PCK26, cMET, CD44v6, HER2, CDCP1, p53, CK15, COX2, VEGFR2, ABCb1, HTF9C, CD10, MRP4, CEACAM5, EGFR, p21, MRP5, SLC7A5, Ki67, DAPI) was performed on a single FFPE TMA section containing cases of DCIS. Briefly, FFPE sections from TMAs containing DCIS were sequentially (cyclically) stained for the markers. Each cycle entailed staining with 2-3 markers followed by imaging, dye inactivation, and re-staining. DAPI was used for nuclear demarcation and for registration of the images, while S6, pan-cadherin, Na+K+ATPase and pan-cytokeratin were used for epithelial segmentation. K-means clustering followed regression analysis was performed to identify inter-relationships between markers and association with likelihood of recurrence. Log-rank analysis was performed and the relapse-free survival data depicted using Kaplan Meier plots. Escore was developed by logistic regression model, classification model on recurrence

Results: Filtering of the expression analysis by the quality, specificity, compartment localization and fields entirely composed of DCIS, in addition to availability of clinical data resulted final analysis of 31 markers in 67 cases. Correlation analyses were performed on each of the markers to identify markers that were significantly correlated in univariate analysis. K-means cluster analysis was performed using a set of 4 markers (ER, HER2, SLC7A5 and cMET) to identify 6 clusters. High cMET (cluster 1; low HER2 and SLC7A5) and High ER (low cMET, HER2, SLC7A5; Cluster 5) were associated with low risk of recurrence (p values 0.014 and <0.0001). In contrast, Cluster 2 (High HER2, high SLC7A5, low ER) and Cluster 3 (High HER2, low ER, SLC7A5and cMET) were associated with increased risk of recurrence (P values 0.038 and 0.076). A regression analysis based algorithm was developed using these markers to calculate a numerical score which could predict likelihood of recurrence. As depicted in the KM plots, the HR for recurrence increases significantly (P-value 2.4E-05; p=0.02 with LOOCV) with increase in expression score (Escore).

Conclusions: We describe the development of an Escore using expression 4 markers to predict likelihood of recurrence. Additional ongoing studies will seek to validate the utility of the Escore in predicting likelihood of recurrence of DCIS and development of invasive carcinomas and comparison with other scoring systems.

Citation Format: Badve SS, Cho S, Gokmen-Polar Y, Zavodszky M, Sui Y, Chadwick C, Tan PH, Gerdes M, Harris AL, Ginty F. Expression score (Escore) for the prediction of likelihood of recurrence of DCIS [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-08-17.

Abstract P3-08-03: Dissecting the heterogeneity of metaplastic breast cancer: A morphological, immunohistochemical and genomic analysis of a large cohort

Although rare, Metaplastic Breast Carcinomas (MBC) account for significant global breast cancer mortality. This subgroup is extremely heterogeneous and by definition exhibits metaplastic change to squamous and/or mesenchymal elements, including but not limited to spindle, squamous, chondroid, osseous and rhabdomyoid elements. The WHO working group recognizes that the current classification is inadequate and in the interim, has suggested a purely descriptive classification. The mixed epithelial-mesenchymal morphology has led to speculation that MBC represent 'stem cell tumours'; in support of this, MBC have been shown to have a CD44+/CD24-/low phenotype. Clinically, patients present with tumours that are larger (higher stage), have increased likelihood of distant metastases at presentation and overall, have a reduced 5-year survival rate compared to Invasive Carcinoma-NST. Hence, this is a unique subtype with poor outcome but without a robust classification or understanding of the biology to aid clinical management. We present a detailed morphological, immunohistochemical and genomic analysis of a large series of MBC (n=347), as amassed through the Asia-Pacific MBC consortium. We consider our morphological dissection using the WHO subtyping guidelines and show that an increasing number of phenotypes in a mixed MBC (classified as WHO_1) significantly associates with a poor prognosis. Immunohistochemical analysis showed that a pure spindle (WHO_5) is significantly less likely to express vimentin, CK5/6, CK14, and CK19 than a mixed WHO_1 with spindle features. Similarly, a WHO_1 with chondroid features is less likely to express EGFR than WHO_1 with chondroid features and rhabdoid or osseous differentiation. Across the cohort, positivity for the AE1/3 antibody and a lack of EGFR expression both significantly associate with a better outcome. We report no significant association between patient age at diagnosis and breast cancer specific survival, nor between age and specific WHO MBC subtypes. We report a significant association between WHO_1 types and increasing tumour grade, and also between tumour size and grade, with tumour size being a highly significant prognostic indicator in this cohort. Our exome sequencing confirms a significant enrichment for TP53 and PTEN mutations in MBC, and intriguingly for concurrent mutations of TP53, PTEN and PIK3CA. A novel enrichment for NF1 mutations is also presented. In summary, we provide a thorough assessment of a large cohort of MBC, including morphology, survival, IHC and exome sequencing, and present our analysis contextualized by the WHO guidelines, extending the existing knowledge base of this rare tumour type.

Citation Format: McCart Reed AE, Kalaw E, Nones K, Bettington M, Lim M, Bennett J, Johnstone K, Kutasovic JR, Kazakoff S, Xu QC, Saunus JM, Reid LE, Black D, Niland C, Ferguson K, Gresshoff I, Raghavendra A, Liu JC, Kalinowski L, Reid AS, Davidson M, Pearson JV, Yamaguchi R, Harris G, Tse G, Papadimos D, Pathmanathan R, Pathmanathan N, Tan PH, Fox S, O'Toole S, Waddell N, Simpson PT, Lakhani SR. Dissecting the heterogeneity of metaplastic breast cancer: A morphological, immunohistochemical and genomic analysis of a large cohort [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-08-03.

Abstract P1-06-02: Impact of heterogeneity of DCIS on immune cell infiltrations

Background: Ductal carcinoma in situ (DCIS) accounts for at least 20% of breast cancers. Factors associated with recurrence of DCIS or progression to invasive carcinoma are not well delineated. The goals of the current study were to profile the epithelial and immune cells using the MultiOmyx hyperplexed immuno-fluorescent based analyses. This was coupled with semi-automated algorithms to characterize the inter-relationships between cell populations within individual DCIS lesions.

Patients and Methods: Analysis for 15 antibody markers (EGFR, Her2, Her4, S6, pMTOR, PCAD, CD44v6, NaKATPase, SLC7A5, CD4, CD8, CD20, CD68, and CD10) was performed on a single FFPE section containing 10-20 distinct ducts from 13 cases of DCIS. Briefly, approximately 40 fields of view (FOV) from digitized sections containing DCIS or normal tissue were sequentially (cyclically) stained for the 15 markers. Each cycle entailed staining with 2-3 markers followed by imaging, dye inactivation, and re-staining. DAPI was used for nuclear demarcation and for registration of the images, while S6, pan-cadherin, Na+K+ATPase and pan-cytokeratin were used for epithelial segmentation. K-means clustering was used to determine patterns of co-expression of markers at the single cell, duct, and patient levels. These clusters were then correlated with immune marker expression by tumor infiltrating lymphocytes (TILs) by marker type (CD4, CD8, and CD20) and tumor compartment (stromal versus intraepithelial).

Results: Analysis of the epithelial component in each of 13 cases of DCIS (n= 415 ducts) revealed 8 distinct expression patterns (clusters) using a panel of 7 markers (EGFR, Her2, Her4, pmTOR, CD44v6, SLC7A5, and CD10). The frequency and distribution of clusters, annotated at the single cell level, showed that 4 DCIS's were dominated (>80%) by a single cell phenotype represented by cluster groups 3 and 7 (high Her2), cluster 6 (High Her4 and SLC7A5 and low Her2), or cluster 4 (non-descript). In 5 pts, the pattern was more heterogeneous consisting of mixture of cell populations with 50-70% of the cells belonging to cluster 1 (moderate to high levels for all markers except EGFR and CD10). The remaining pts had a strong representation of cluster 4 and 5 (CD44v6 and phospho-mTOR) cells. The distribution of both intra-epithelial and stromal TILs in DCIS cases were either consisted of a mixed B-cell (CD20+) and T-cell response (n=4), or one dominated by T-cells. Cluster 2 (High EGFR and CD10) was associated with a largely T-cell response (rs = 0.83, P value = 0.0004), while Cluster 7 (strong HER2) was associated with a B-cell response (rs = 0.68, P value = is 0.009).

Conclusions: Analysis 15 markers and use of K-means clustering algorithm, shows prominent inter-tumoral (but not intra-tumoral) heterogeneity in DCIS. Furthermore, epithelial cell specific clusters (high HER2 or EGFR) were associated with distinct B or T cell infiltration by TILs. Additional ongoing studies will determine the clinical significance of the clusters with respect to recurrence of DCIS and development of invasive carcinomas.

Citation Format: Badve S, Gökmen-Polar Y, Harris AL, Sui Y, Sevinsky C, Santamaria-Pang A, Ginty F, Tan PH, Gerdes MJ. Impact of heterogeneity of DCIS on immune cell infiltrations [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-06-02.

ERRATUM: Phyllodes tumours of the breast: retrospective analysis of a University Hospital's experience

No abstract available.

Evolving role of adiponectin in cancer-controversies and update

Adiponectin (APN), an adipokine produced by adipocytes, has been shown to have a critical role in the pathogenesis of obesity-associated malignancies. Through its receptor interactions, APN may exert its anti-carcinogenic effects including regulating cell survival, apoptosis and metastasis via a plethora of signalling pathways. Despite the strong evidence supporting this notion, some work may indicate otherwise. Our review addresses all controversies critically. On the whole, hypoadiponectinaemia is associated with increased risk of several malignancies and poor prognosis. In addition, various genetic polymorphisms may predispose individuals to increased risk of obesity-associated malignancies. We also provide an updated summary on therapeutic interventions to increase APN levels that are of key interest in this field. To date efforts to manipulate APN levels have been promising, but much work remains to be done.

Phyllodes tumours of the breast: retrospective analysis of a University Hospital's experience

Taking cognizance of the purported variation of phyllodes tumours in Asians compared with Western populations, this study looked at phyllodes tumours of the breast diagnosed at the Department of Pathology, University of Malaya Medical Centre over an 8-year period with regards to patient profiles, tumour parameters, treatment offered and outcome. Sixty-four new cases of phyllodes tumour were diagnosed during the period, however only 30 (21 benign, 4 borderline and 5 malignant) finally qualified for entry into the study. These were followed-up for 4-102 months (average = 41.7 months). Thirteen cases (8 benign, 3 borderline, 2 malignant) were Chinese, 9 (all benign) Malay, 7 (4 benign, 1 borderline, 2 malignant) Indian and 1 (malignant) Indonesian. Prevalence of benign versus combined borderline and malignant phyllodes showed a marginally significant difference (p=0.049) between the Malays and Chinese. Patients' ages ranged from 21-70 years with a mean of 44.9 years with no significant difference in age between benign, borderline or malignant phyllodes tumours. Except for benign phyllodes tumours (mean size = 5.8 cm) being significantly smaller at presentation compared with borderline (mean size = 12.5 cm) and malignant (mean size = 15.8 cm) (p<0.05) tumours, history of previous pregnancy, breast feeding, hormonal contraception and tumour laterality did not differ between the three categories. Family history of breast cancer was noted in 2 cases of benign phyllodes. Local excision was performed in 17 benign, 2 borderline and 3 malignant tumours and mastectomy in 4 benign, 2 borderline and 2 malignant tumours. Surgical clearance was not properly recorded in 10 benign phyllodes tumours. Six benign and all 4 borderline and 5 malignant tumours had clearances of <10 mm. Two benign tumours recurred locally at 15 and 49 months after local excision, however information regarding surgical clearance was not available in both cases. One patient with a malignant tumour developed a radiologically-diagnosed lung nodule 26 months after mastectomy, was given a course of radiotherapy and remained well 8-months following identification of the lung nodule.

Genetic Interactions Between TRPC6 and NPHS1 Variants Affect Posttransplant Risk of Recurrent Focal Segmental Glomerulosclerosis

Individuals with TRPC6 mutations have variable phenotypes, ranging from healthy carrier to focal segmental glomerulosclerosis (FSGS) leading to renal failure. Here, we describe a family where six members had a novel TRPC6 p.R68W (c.202C>T) mutation, two of whom had renal failure from FSGS, and one had proteinuria. One healthy carrier donated a kidney to her sister. Both donor and recipient had no proteinuria at 20 years posttransplant. Two synonymous NPHS1 polymorphisms, rs2285450 (c.294C>T) and rs437168 (c.2289C>T) segregated with renal failure in this family. These variants had higher allele frequencies in 97 unrelated patients with nephrotic syndrome or FSGS compared to 224 controls. Using patch-clamp experiments in HEK293 and podocytes, we showed that the p.R68W mutation increased TRPC6 current amplitudes, which may be explained by enhanced TRPC6 surface expression. Additionally, while wild-type nephrin suppressed TRPC6 currents, this ability was lost in the presence of NPHS1 c.294C>T polymorphism. When cells were transfected according to combined TRPC6 and NPHS1 genotypes in the family, those representing the donor had lower TRPC6 currents than cells representing the recipient, suggesting that interactions between TRPC6 and NPHS1 variants could possibly account for the variable penetrance of TRPC6 mutations and the absence of recurrence in the graft.

Prognostic factors in metaplastic carcinoma of the breast: a multi-institutional study

Background:

Metaplastic breast carcinoma (MBC) is a rare type of breast cancer that has basal-like characteristics and is perceived to have poorer prognosis when compared with conventional no specific type/ductal carcinomas (ductal/NST). However, current data on MBC are largely derived from small case series or population-based reports. This study aimed to assess the clinicopathological features and outcome of MBC identified through an international multicentre collaboration.

Methods:

A large international multicentre series of MBC (no=405) with histological confirmation and follow-up information has been included in this study. The prognostic value of different variables and outcome has been assessed and compared with grade, nodal status and ER/HER2 receptor-matched ductal/NST breast carcinoma.

Results:

The outcome of MBC diagnosed in Asian countries was more favourable than those in Western countries. The outcome of MBC is not different from matched ductal/NST carcinoma but the performance of the established prognostic variables in MBC is different. Lymph node stage, lymphovascular invasion and histologic subtype are associated with outcome but tumour size and grade are not. Chemotherapy was associated with longer survival, although this effect was limited to early-stage disease. In this study no association between radiotherapy and outcome was identified. Multivariate analysis of MBC shows that histologic subtype is an independent prognostic feature.

Conclusions:

This study suggests that MBC is a heterogeneous disease. Although the outcome of MBC is not different to matched conventional ductal/NST breast carcinoma, its behaviour is dependent on the particular subtype with spindle cell carcinoma in particular has an aggressive biological behaviour. Management of patients with MBC should be based on validated prognostic variables.

Adiponectin receptor signaling on dendritic cells blunts antitumor immunity

Immune escape is a fundamental trait of cancer. Dendritic cells (DC) that interact with T cells represent a crucial site for the development of tolerance to tumor antigens, but there remains incomplete knowledge about how DC-tolerizing signals evolve during tumorigenesis. In this study, we show that DCs isolated from patients with metastatic or locally advanced breast cancer express high levels of the adiponectin receptors AdipoR1 and AdipoR2, which are sufficient to blunt antitumor immunity. Mechanistic investigations of ligand-receptor interactions on DCs revealed novel signaling pathways for each receptor. AdipoR1 stimulated IL10 production by activating the AMPK and MAPKp38 pathways, whereas AdipoR2 modified inflammatory processes by activating the COX-2 and PPARγ pathways. Stimulation of these pathways was sufficient to block activation of NF-κB in DC, thereby attenuating their ability to stimulate antigen-specific T-cell responses. Together, our findings reveal novel insights into how DC-tolerizing signals evolve in cancer to promote immune escape. Furthermore, by defining a critical role for adiponectin signaling in this process, our work suggests new and broadly applicable strategies for immunometabolic therapy in patients with cancer.

Validation of a nomogram in the prediction of local recurrence risks after conserving surgery for Asian women with ductal carcinoma in situ of the breast

AIMS

At our centre, ductal carcinoma in situ (DCIS) was commonly treated with breast-conservation therapy (BCT). Local recurrence after BCT is a major concern. The aims of our study were to review the outcomes of DCIS treatment in our patients and to evaluate a nomogram from Memorial Sloan Kettering Cancer Centre (MSKCC) for predicting ipsilateral breast tumour recurrence (IBTR) in our Asian population.

MATERIALS AND METHODS

Chart reviews of 716 patients with pure DCIS treated from 1992 to 2011 were carried out. Univariable Cox regression analyses were used to evaluate the effects of the 10 prognostic factors of the MSKCC nomogram on IBTR. We constructed a separate National Cancer Centre Singapore (NCCS) nomogram based on multivariable Cox regression via reduced model selection by applying the stopping rule of Akaike's information criterion to predict IBTR-free survival. The abilities of the NCCS nomogram and the MSKCC nomogram to predict IBTR of individual patients were evaluated with bootstrapping of 200 sets of resamples and the NCCS dataset, respectively. Harrell's c-index was calculated for each nomogram to evaluate the concordance between predicted and observed responses of individual subjects.

RESULTS

Study patients were followed up for a median of 70 months. Over 95% of patients received adjuvant radiotherapy. The 5 and 10 year actuarial IBTR-free survival rates for the cohort were 95.5 and 92.6%, respectively. In the multivariate analysis, independent prognostic factors for IBTR included use of adjuvant endocrine therapy, presence of comedonecrosis and younger age at diagnosis. These factors formed the basis of the NCCS nomogram, which had a similar c-index (NCCS: 0.696; MSKCC: 0.673) compared with the MSKCC nomogram.

CONCLUSION

The MSKCC nomogram was validated in an Asian population. A simpler NCCS nomogram using a different combination of fewer prognostic factors may be sufficient for the prediction of IBTR in Asians, but requires external validation to compare for relative performance.

Carrier and polarization dynamics in monolayer MoS2

In monolayer MoS2, optical transitions across the direct band gap are governed by chiral selection rules, allowing optical valley initialization. In time-resolved photoluminescence (PL) experiments, we find that both the polarization and emission dynamics do not change from 4 to 300 K within our time resolution. We measure a high polarization and show that under pulsed excitation the emission polarization significantly decreases with increasing laser power. We find a fast exciton emission decay time on the order of 4 ps. The absence of a clear PL polarization decay within our time resolution suggests that the initially injected polarization dominates the steady-state PL polarization. The observed decrease of the initial polarization with increasing pump photon energy hints at a possible ultrafast intervalley relaxation beyond the experimental ps time resolution. By compensating the temperature-induced change in band gap energy with the excitation laser energy, an emission polarization of 40% is recovered at 300 K, close to the maximum emission polarization for this sample at 4 K.

Abstract P4-05-10: PIK3CA mutations are enriched in invasive lobular carcinomas and invasive mammary carcinomas with lobular features: Results from a TCGA sub-analysis

Background: Aberrant signaling via the PI3K pathway is a common alteration in breast cancer (BC), with frequent activating mutations in the PIK3CA gene helical (exon 9) and catalytic (exon 20) domains. These mutations occur across all BC subtypes with an overall incidence of 36%, with the highest frequency (∼45%) in luminal A/ER+ tumors. Lobular phenotype is common among luminal A tumors. We examined associations between lobular histology and molecular features among BC samples submitted for comprehensive molecular analyses for The Cancer Genome Atlas (TCGA).

Design: Experts in breast pathology reviewed digital slides of breast cancer samples submitted for comprehensive molecular profiling to the TCGA. Tumors were graded, subtyped and scored for additional histopathologic features. We tested pairwise associations between lobular features and components of grade, PAM50-derived molecular subtype and mutational status for BRAC1/2, PIK3CA, TP53 and CDH1 by performing Chi-Square analysis for comparisons with a categorical variable and the Mann-Whitney test for comparisons with an ordinal variable

Results: A total of 1132 images were scored from 589 unique cases in TCGA. For cases with multiple scorers (43% of cases), we summarized scores by taking the median (for ordinal variables) or the consensus diagnosis (for categorical variables). A total of 567 cases had a consensus diagnosis for lobular features, all of which had pathological information on components of histologic grade and 540 of which had data for TP53, CDH1, and PIK3CA mutations. 110/567 (19%) of cases were classified as invasive lobular or invasive mammary carcinoma with lobular features. The lobular cases had significantly less nuclear pleomorphism (p = 3.3 e -12), lower mitotic index (p = 3.4e-16), less tubule formation (p = 3.9e-8), increased association with lobular carcinoma in situ (p &lt; 2.2 e-16), decreased stromal inflammation (p = 1.5e-7), and decreased necrosis (p = 4.4e-11) compared with cases without lobular features. Cases with lobular features were highly enriched for CDH1 mutations with 19% of cases with lobular features having CDH1 mutations, compared with only 1% of cases without lobular features (p = 2.4 e-14). The lobular features cases were more likely to have PIK3CA mutations (p = 0.01), with 33% of the lobular features cases having PIK3CA mutations, compared with 21% of the non-lobular cases. The lobular features cases were less likely to have TP53 mutations (p = 0.02), with 13% of lobular features cases having TP53 mutations as compared with 24% of the non-lobular feature cases. Lobular status was associated with PAM50 molecular subtype (Chi-square p = 0.002) with the lobular cases significantly less likely to be basal molecular subtype and more likely to be Luminal-A.

Conclusions: PIK3CA mutations are enriched in invasive lobular carcinomas and invasive mammary carcinomas with lobular features. These associations point to the possibility that PIK3CA mutations as well as CDH1 alterations are important drivers of invasive lobular carcinomas.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-05-10.

Abstract P4-05-15: Breast cancers with BRCA1 and BRCA2 mutations are associated with specific pathologic features and molecular profiles: Results from a TCGA sub-analysis

Background: Previous studies have found that particular pathologic features are more common in breast cancers arising in BRCA mutation carriers. However, the biologic and molecular bases for the morphologic associations are not clear. This study is conducted to analyze pathologic and molecular features in tumors stratified by BRCA1 or BRCA2 mutation status using the breast cancer samples that have comprehensive molecular portraits characterized by the Cancer Genome Atlas (TCGA).

Methods: The digital slides of breast cancer samples submitted for comprehensive molecular profiling to the TCGA were reviewed by expert breast pathologists, who were unaware of the BRCA status or other molecular signatures. Each tumor was evaluated and scored for histologic type, nuclear pleomorphism, tubule formation, mitosis, stromal inflammation, and necrosis. 562 cases had both pathology and tumor exome sequencing data available and constituted the current study population. We determined the association of somatic BRCA1 and BRCA2 mutation status with pathologic features and molecular characteristics (mutation of PIK3CA and TP53, and molecular subtypes defined by PAM50 mRNA data) using the Fisher exact test for categorical variables and the Wilcoxon test for ordinal variables.

Results: Of the 562 tumors, 514 had no BRCA1 or BRCA2 mutation, while 48 (8.5%) of tumors were found to harbor a BRCA1 mutation (n = 16, 3%), BRCA2 mutation (n = 30, 5%), or mutation in both (n = 2, 0.3%). BRCA1 and BRCA2 mutational status showed no significant association with lobular features, tubule formation, nuclear pleomorphism, or stromal inflammation (all p &gt; 0.05), although there was a trend for increased nuclear pleomorphism in BRCA2 mutant cases (p = 0.07). The lack of significant association of BRCA1/2 mutational status with these features may be due to our study's relatively small number of BRCA1/2 mutant cases. Both BRCA1 and BRCA2 mutations were associated with a higher mitotic count (p = 0.03 and 0.04, respectively). BRCA2 mutation showed no association with necrosis (p = 1), while BRCA1 mutation status was associated with increased necrosis (OR = 2.7, p = 0.04). BRCA2 mutation status showed no significant association with PAM50 subtype (p = 0.37), while BRCA1 mutation status was significantly associated with PAM50 molecular subtype (p = 0.005), with the greatest enrichment among Basal-like (7/70 Basal-like with BRCA1 mutation, 10%) and depletion among Luminal-B (0/79 Luminal-B with BRCA1 mutation, 0%). Neither BRCA1 nor BRCA2 mutations were significantly association with PIK3CA mutations (p = 0.39, 0.08, respectively). BRCA2 mutation status was not associated with TP53 mutations (p = 0.65), while BRCA1 mutation status was associated with increased TP53 mutations (OR = 4.0, p = 0.005).

Conclusion: Tumors with BRCA1 and BRCA2 alterations are associated with specific pathologic and molecular features. However, there is molecular and morphologic heterogeneity within these cancers. These factors need to be considered when designing algorithms for BRCA testing and targeted therapy in BRCA-related cancers.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-05-15.

Abstract P4-05-06: Host inflammation and breast cancer molecular subtypes: Updated results from a TCGA sub-analysis

Background: There is increasing evidence that the presence of a host inflammatory response to breast cancer may influence outcomes. Utilizing inflammation scores on the histology of breast cancer samples submitted for comprehensive molecular analyses for The Cancer Genome Atlas (TCGA), we provide an updated look at associations between the presence of host inflammation and breast cancer molecular and pathologic features.

Design: Experts in breast pathology reviewed the digital slides of breast cancer samples submitted for comprehensive molecular profiling to the TCGA and scored each case for the level of inflammation present (high/moderate vs mild/minimal). We tested pairwise associations between host inflammation and molecular subtypes (DNA copy-number, RNA expression, RPPA defined subtypes, miRNA subtypes, methylation subtypes) and pathological features by performing Chi-Square analyses. Multiple hypothesis testing correction was performed using the Bonferroni method.

Results: 598 breast cancer cases with TCGA molecular profiling data were scored by the expert breast pathologists for morphological features (including inflammation). 195 (33%) of these were scored as high/moderate inflammation. Cases with inflammation had a significantly higher rate of TP53 mutations (p = 9.0e-8) with 64 of 118 (54.2%) p53 mutant cases with inflammation. Inflammation was also significantly associated with PAM50 molecular subtypes (p = 2.2e-11), with the greatest enrichment among basal-like (64.5% of 70 basal-like cases had inflammation) and the greatest depletion among Luminal A (18.1% of 166 Luminal A cases had inflammation). Cases with inflammation were significantly less likely to be lobular (p = 1.5e-7), had less tubule formation (p = 0.0006), increased mitoses (p &lt;2.2 e-16), increased nuclear pleomorphism (p = 2.9e-15), and increased necrosis (p = 2.9e-14).

Conclusions: There are strong associations between breast cancer molecular and pathological features and the host inflammatory response.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-05-06.

Mesenchymal stem cells differentially mediate regulatory T cells and conventional effector T cells to protect fully allogeneic islet grafts in mice

AIMS/HYPOTHESIS

Limited information is available on the cellular interactions between regulatory T (T(reg)) cells and mesenchymal stem cells (MSCs). In particular, a direct effect of MSCs on the survival and proliferation of T(reg) cells has not been demonstrated.

METHODS

We investigated the effects of MSCs on effector T (T(eff)) cells and T(reg) cells, and the molecular mechanisms involved in the distinct regulation of these two cell populations by MSCs in vivo and in vitro.

RESULTS

We show that MSCs are capable of selectively suppressing T(eff) cells and fostering the generation of T(reg) cells. T(eff) cells, but not T(reg) cells, fail to respond to IL-2 and undergo profound apoptosis in the presence of MSCs. The differential regulations of these two T cell subsets by MSCs are associated with their distinct expressions of CD25, with MSCs specifically reducing the expression of CD25 on T(eff) and sparing T(reg) cells intact. In vivo, the administration of MSCs significantly delays the rejection of allogeneic islet grafts in adaptive transferred recipients by favouring the induction of T(reg) cells. In this model, MSCs inhibit the proliferation and development of alloreactive T(eff) but potently enhance the induction of T(reg) cells.

CONCLUSIONS/INTERPRETATION

We demonstrate that MSCs are capable of regulating T(eff) and T(reg) cells differentially in vitro. MSCs inhibit T(eff) cells by inducing apoptosis and impairing the proliferative response to IL-2 in T(eff) cells, but favour the survival and expansion of T(reg) cells. This result is further demonstrated in mice that have undergone allogeneic islet transplantation, in which MSCs suppress alloreactive T(eff) cells while favouring the induction of T(reg) cells, thus protecting the islet allografts from rejection.

The shear mode of multilayer graphene

The quest for materials capable of realizing the next generation of electronic and photonic devices continues to fuel research on the electronic, optical and vibrational properties of graphene. Few-layer graphene (FLG) flakes with less than ten layers each show a distinctive band structure. Thus, there is an increasing interest in the physics and applications of FLGs. Raman spectroscopy is one of the most useful and versatile tools to probe graphene samples. Here, we uncover the interlayer shear mode of FLGs, ranging from bilayer graphene (BLG) to bulk graphite, and suggest that the corresponding Raman peak measures the interlayer coupling. This peak scales from ~43 cm(-1) in bulk graphite to ~31 cm(-1) in BLG. Its low energy makes it sensitive to near-Dirac point quasiparticles. Similar shear modes are expected in all layered materials, providing a direct probe of interlayer interactions.

Short small-interfering RNAs produce interferon-α-mediated analgesia

BACKGROUND

There is increasing interest in RNA interference in pain research using the intrathecal route to deliver small-interfering RNA (siRNA). An interferon (IFN) response is a common side-effect of siRNA. However, the IFN response in the spinal cord after intrathecal administration of siRNA remains unknown. We hypothesized that high doses of siRNAs can elicit off-target analgesia via releasing IFN-α. We investigated the IFN response and its role in regulating pain sensitivity in the spinal cords after intrathecal administration of siRNAs.

METHODS

Male Sprague-Dawley rats were given intrathecal injections of non-targeting (NT) siRNAs or IFN-α and tested for complete Freund's adjuvant (CFA)-induced mechanical allodynia and heat hyperalgesia. IFN-α in the spinal cord after injection of NT siRNAs was measured by western blotting and immunohistochemical staining.

RESULTS

IFN-α was up-regulated in the spinal cord after intrathecal treatment of NT siRNAs. Intrathecal injection of NT siRNAs, at high doses of 10 or 20 μg, reduced CFA-induced inflammatory pain (P<0.05). Intrathecal application of IFN-α inhibited pain hypersensitivity in inflamed rats and produced analgesia in naïve rats (P<0.05). Notably, the anti-nociceptive effects elicited by NT siRNAs and IFN-α were reversed by IFN-α neutralizing antibody and naloxone.

CONCLUSIONS

Our data suggest that (i) intrathecal administration of high doses of siRNA (≥ 10 μg) induced up-regulation of IFN-α in the spinal cord and produced analgesic effects through IFN-α, and (ii) IFN-α's analgesic effect is mediated via opioid receptors. Caution must be taken to avoid IFN-α-mediated analgesic effects of siRNAs in pain research.

Vascular endothelial growth factor receptors and the therapeutic targeting of angiogenesis in cancer: where do we go from here?

Abstract Vascular Endothelial Growth Factor receptors (VEGFRs), the interactions with their ligands and the subsequent signalling pathways are known to play a vital role in tumour angiogenesis. Initial clinical trials of VEGFR inhibitors were disappointing but over the past decade some therapies have been successfully brought to market. At present, VEGFR inhibitors appear to be most promising as adjuvants to conventional chemotherapy. However, several interacting signalling molecules and downstream pathways have recently been shown to interact with VEGFR signalling and provide promising novel targets, such as the platelet-derived growth factor (PDGF), epithelial growth factor (EGF), human epithelial receptor-2, (HER-2) Tie-2 and oestrogen receptors. Elucidation of this web of signalling pathways may identify new therapeutic strategies which may be used in combination with VEGFR inhibitors to augment the efficacy of anti-angiogenic cancer treatments. This review assesses the role of modulating VEGFR activity in cancer and systematically examines current evidence and trials in this area.

Controlling the cost of breast cancer

Breast cancer management is an important part of the health-care system. In the current harsh economic climate, these costs have to be controlled, and achieving this without compromising quality of care is a daunting challenge. This article discusses the need to find effective and well-targeted chemotherapeutic regimens, which, when combined with appropriate implementation of novel strategies, will provide the optimum treatment for patients while maintaining economic viability.

Gefitinib, cisplatin, and concurrent radiotherapy for locally advanced head and neck cancer: EGFR FISH, protein expression, and mutational status are not predictive biomarkers

BACKGROUND

Gefitinib was demonstrated to be synergistic with cisplatin and radiotherapy (RT) in in vitro studies. Biomarkers predictive of response to gefitinib in squamous cell head and neck cancer is still lacking.

METHODS

Thirty-one patients with locally advanced and easily accessible primary tumor sites for biopsies were recruited. Gefitinib was started 3 weeks before the start of cisplatin/concurrent radiotherapy (CTRT) and continued during the CTRT phase and thereafter for 4 months as consolidation phase. Two baselines and a repeat tumor sample were taken after 2 weeks of gefitinib alone to study its impact on tumor gene expression. Epidermal growth factor receptor (EGFR) protein expression, FISH and mutational status, and matrix metallopeptidase 11 (MMP11) protein expression were correlated with response and survival outcome.

RESULTS

The overall response rate to gefitinib alone was 9.7%. The survival outcome is as follows: median disease free 1.3 years, median survival time 2.4 years, 3-year disease free 42.9%, and 3-year overall survival 48.4%. EGFR FISH, protein expression, and mutational status did not predict for response nor survival outcome of patients. Although MMP11 overexpression did not predict for response, it predicted significantly for a poorer survival outcome.

CONCLUSIONS

Gefitinib can be combined safely with cisplatin/RT. More studies are needed to uncover predictive biomarkers of benefit to gefitinib.

Induction of pathogenic cytotoxic T lymphocyte tolerance by dendritic cells: a novel therapeutic target

IMPORTANCE OF THE FIELD

Dendritic cells (DCs) have an important role, both direct and indirect, in controlling the expansion and function of T cells. Of the different subsets of T cells, cytotoxic T lymphocytes (CTLs/CD8(+) T cells) have been implicated in the pathogenesis and development of many diseases, including various forms of autoimmunity and transplant rejection. It may therefore be of therapeutic benefit to control the function of CTL in order to modulate disease processes and to ameliorate disease symptoms. Currently, pharmacological approaches have been employed to either directly or indirectly modulate the function of T cells. However, these treatment strategies have many limitations. Many experimental data have suggested that it is possible to alter CTL activity through manipulation of DC.

AREAS COVERED IN THIS REVIEW

Novel strategies that condition DCs to influence disease outcome through manipulation of CTL activity, both directly and indirectly. This includes the modulation of co-stimulation, negative co-stimulation, as well as manipulation of the cytokine milieu during CTL generation. Furthermore, DCs may also impact CTL activity through effects on effector and regulatory cells, along with manipulation of bioenergetic regulation, apoptotic-cell mediated tolerance and through the generation of exosomes. The implications of related interventions in the clinical arena are in turn considered.

WHAT THE READER WILL GAIN

Insight into such indirect methods of controlling CTL activity allows for an understanding of how disease-specific T cells may be regulated, while also sparing other aspects of adaptive immunity for normal physiological function. Such an approach towards the treatment of disease represents an innovative therapeutic target in the clinical arena.

TAKE HOME MESSAGE

There are numerous innovative methods for using DCs to control CTL responses. Manipulation of this interaction is thus an attractive avenue for the treatment of disease, particularly those of immune dysregulation, such as seen in autoimmunity and transplantation. With the number of studies moving into clinical stages constantly increasing, further advances and successes in this area are inevitable.

Good outcomes with mycophenolate-cyclosporine-based induction protocol in children with severe proliferative lupus nephritis

The outcomes of children with severe proliferative lupus nephritis (LN) were examined using a new mycophenolate and cyclosporine-based (MMF-CSA) induction protocol. Sixteen children with LN (WHO class III and IV), 31.3% of whom required dialysis at induction, were retrospectively studied. Median MMF dose was 942 mg/m( 2)/day. Thirteen patients (81%) with persistent proteinuria received CSA. Clinical and laboratory parameters were compared at pre-induction, 6 and 12 months. Treatment outcome was defined by Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), renal function, haematuria, proteinuria and serological markers (complements C3, C4 and anti-dsDNA). Comparing these parameters at induction, 6 months and 12 months, respectively, SLEDAI (25.4 +/- 8.7 versus 3.2 +/- 2.9 versus 2.9 +/- 2.8), serum C3 (47 +/- 21 versus 107 +/- 27 versus 111 +/- 38 mg/dl), C4 (12 +/- 14 versus 23 +/- 14 versus 22 +/- 11 mg/dl) and urine protein (6.97 +/- 7.09 versus 0.98 +/- 1.56 versus 0.21 +/- 0.13 g/ day/1. 73 m(2)) improved significantly (p < 0.05). Anti-dsDNA titres decreased in 73% by 6 and 12 months (p < 0.05). Complete renal remission was achieved in 7/16 (43.8%) at 6 months and 12/16 (75%) at 12 months, the rest achieving partial remission with no treatment failures. In conclusion, a combination MMF-CSA protocol is an effective therapeutic alternative for induction of children with severe proliferative LN, resulting in significant clinical and serological improvement with minimal adverse effects.

Manipulation of indoleamine 2,3 dioxygenase; a novel therapeutic target for treatment of diseases

BACKGROUND

The discovery of indoleamine 2,3-dioxygenase (IDO) as a modulator for the maintenance of fetomaternal immuno-privileged state has been heralded as a significant step in further defining the role of IDO in immunobiology. IDO is an IFN-inducible, intracellular enzyme that catalyzes the initial and rate-limiting step in the degradation of the essential amino acid, tryptophan. It has been suggested that IDO has the capacity to regulate the immune system via two discrete mechanisms; firstly the deprivation of tryptophan, which is essential for T cell proliferation and via the cytotoxic effects of tryptophan metabolites on T(H)1 cell survival.

METHODS

The sources of information used to prepare the paper are published work on Pubmed/Medline. In this review, we examine the therapeutic role of modulating IDO activity a variety of disease states including tumour tolerance, chronic infection, transplant rejection, autoimmunity and asthma. We propose that IDO represents a novel therapeutic target for the treatment of these diseases. We also explore the diverse strategies which are being employed, either to augment or to inhibit IDO activity in order to modify various disease processes. The limitations associated with these strategies are also scrutinized.

LARG at chromosome 11q23 has functional characteristics of a tumor suppressor in human breast and colorectal cancer

Deletion of 11q23-q24 is frequent in a diverse variety of malignancies, including breast and colorectal carcinoma, implicating the presence of a tumor suppressor gene at that chromosomal region. We examined a 6-Mb region on 11q23 by high-resolution deletion mapping, using both loss of heterozygosity analysis and customized microarray comparative genomic hybridization. LARG (leukemia-associated Rho guanine-nucleotide exchange factor) (also called ARHGEF12), identified from the analysed region, is frequently underexpressed in breast and colorectal carcinomas with a reduced expression observed in all breast cancer cell lines (n=11), in 12 of 38 (32%) primary breast cancers, 5 of 10 (50%) colorectal cell lines and in 20 of 37 (54%) primary colorectal cancers. Underexpression of the LARG transcript was significantly associated with genomic loss (P=0.00334). Hypermethylation of the LARG promoter was not detected in either breast or colorectal cancer, and treatment of four breast and four colorectal cancer cell lines with 5-aza-2'-deoxycytidine and/or trichostatin A did not result in a reactivation of LARG. Enforced expression of LARG in breast and colorectal cancer cells by stable transfection resulted in reduced cell proliferation and colony formation, as well as in a markedly slower cell migration rate in colorectal cancer cells, providing functional evidence for LARG as a candidate tumor suppressor gene.

Manipulation of indoleamine 2,3-dioxygenase (IDO) for clinical transplantation: promises and challenges

BACKGROUND

Since the discovery that indoleamine 2,3-dioxygenase (IDO) is a modulator for maintenance of fetomaternal immuno-privilege state, it has been implicated in tumour tolerance, autoimmune diseases and asthma. IDO is an IFN-gamma-inducible, intracellular enzyme that catalyzes the initial and rate-limiting step in the degradation of tryptophan. It has been suggested that IDO can regulate the immune system either through deprivation of tryptophan that is essential for T cell proliferation or via cytotoxic effects of kynurenine pathway metabolites on T cell survival.

METHODS

The sources of information used were obtained through Pubmed/Medline.

RESULTS/CONCLUSION

While IDO emerges as a regulator of immunity, its role in controlling allo-response is unfolding. IDO can control T cell responses to allo-antigens and induce generation of allo-specific regulatory T cells. Exploiting IDO as a modulator of transplant rejection, many groups have manipulated its activity to prolong allograft survival in transplantation models. Despite the initial promise, its application to clinical transplantation may be limited. We therefore examine the potentials and limitations associated with clinical translation of IDO into a therapeutic.

Interaction of current cancer treatments and the immune system: implications for breast cancer therapeutics

Early diagnosis and treatment of breast cancer may account for the current improvement in the mortality of breast cancer. However, achieving a complete 'cure' is the holy grail of cancer medicine and, in many cases, cancer patients still succumb to their ultimate fate. There is therefore a need to devise innovative therapies to overcome this problem. To this end, many emerging therapies utilizing the immune system to eradicate the residues of disease have been described in the preclinical and clinical arenas. However, there is very little work examining the impact of immunotherapy on the existing natural immunity. The relationship between antitumor immunity, in the form of immunotherapy (either passive or active), and current strategies of treatment also needs to be explored. If we are to improve the success of cancer treatment, we must understand how current therapies interact with the immune system and with the emerging immunotherapies. For breast-cancer treatment to be successful, therapeutics should be tailored towards antitumor immunity; they should also avoid tumor-specific tolerance. The sources of information used to prepare this paper were obtained through published work on Pubmed/Medline and materials published on the US/UK governmental agencies' websites.

The role of immunohistochemistry in the differential diagnosis of papillary lesions of the breast

Papillary lesions of the breast represent a heterogeneous group with differing biological behaviour. Correct diagnosis is crucial but may be difficult, as many benign and malignant papillary lesions have similar appearances. Immunohistochemistry plays a useful role in their differentiation. Myoepithelial markers can help in differentiating papilloma from papillary carcinoma, as the former usually shows a continuous layer of myoepithelial cells. In intracystic papillary carcinoma, there is controversy as to the presence of a complete myoepithelial cell layer around these lesions. p63 is the marker of choice as the staining is nuclear, cross-reactivity is minimal, and sensitivity is high. Papilloma may frequently be complicated by superimposed different types of epithelial hyperplasia, which range from usual to atypical or even ductal carcinoma in situ, and they many be morphologically similar. Basal cytokeratins (CKs) are useful to differentiate these entities; as usual hyperplasia is positive for basal CKs with a mosaic staining pattern. CK5/6 is probably the best marker. Neuroendocrine markers (chromogranin A and synaptophysin) may be positive in papillary carcinoma, particularly in the solid type, and there may be some overlap with the ductal carcinoma in situ with spindle cells or endocrine ductal carcinoma in situ. A panel of CK5/6, p63 and neuroendocrine markers can be useful in the diagnostic investigation of problematic papillary lesions of the breast. As the experience with these markers remains rather limited, it is too early to recommend basing treatment choices on these marker studies alone. Complete removal of lesion is probably still the treatment of choice.

Adenoid cystic carcinoma of the breast

Adenoid cystic carcinoma of the breast is a rare neoplasm that constitutes less than one percent of all mammary carcinomas. To date, there have been about 140 cases reported in the literature. It is a rare variant of adenocarcinoma that usually occurs in the salivary glands. In contrast to the aggressive nature of adenoid cystic carcinoma that occurs in the head and neck region, adenoid cystic carcinoma of the breast has a very favourable prognosis. Little has been published to date on its radiological features. We describe a 63-year-old woman with adenoid cystic carcinoma detected on mammography in our national breast screening programme, the radiological findings at presentation, the surgical management and a review of the literature.

Imaging of painful solitary lesions of the sacrum

In patients with sacral pain, the painful symptoms may be caused by a variety of bony and soft tissue lesions. Benign lesions include giant cell tumour, neurogenic tumour, insufficiency fracture, infection and giant bone island. Malignant lesions include primary bone tumours, Ewing sarcoma, plasmacytoma, lymphoma and chordoma. Soft tissue tumours adjacent to or involving the sacrum may cause painful symptoms. A multimodality approach to imaging is required for full assessment of these lesions. This pictorial essay describes a range of common solitary sacral lesions that may cause pain, with emphasis on imaging features.

Photoluminescence spectroscopy of carbon nanotube bundles: evidence for exciton energy transfer

We investigate photoluminescence of nanotube bundles. Their spectra are explained by exciton energy transfer between adjacent tubes, whereby excitation of large gap tubes induces emission from smaller gap ones. The consequent relaxation rate is faster than nonradiative recombination, leading to enhanced photoluminescence of acceptor tubes.

Mucinous breast lesions: diagnostic challenges

Breast lesions with mucin represent a broad spectrum of entities, ranging from benign fibrocystic changes with luminal mucin to mucocele-like lesions (MLL), which can be associated with banal epithelial alterations, atypical ductal hyperplasia or ductal carcinoma in situ. Occasionally invasive mucinous carcinoma can be identified in contiguity with MLL. Diagnostic challenges are enumerated, histological differentials are discussed, and a practical approach towards resolving some of these issues is provided. In addition to these lesions with abundant extracellular mucin, there are also conditions that feature stromal mucinous or myxoid material, as well as rare entities that demonstrate both epithelial extracellular and stromal mucin.

Changing viral tropism using immunoliposomes alters the stability of gene expression: implications for viral vector design

Many strategies for redirecting the tropism of murine Moloney leukemia virus (MMLV) have been described. Preformed virion-liposome complexes, termed virosomes, have been reported to be relatively stable. Virosomes mediate envelope-independent transduction that allows efficient superinfection of resistant cell lines; however, virosome-mediated transduction behaves in a non-target-specific manner. We developed a novel method using antibodies to direct MMLV to vascular endothelium. We have given the term immunovirosomes to the complexes formed between viruses, liposomes, and antibodies. These immunovirosomes improve the transduction efficiency of the viruses and alter their tropism. We have shown improved transduction when immunovirosomes were targeted at the endocytic receptors CD71 and CD62E/P and rather less good delivery when targeted at CD106. The enhancement of the transduction efficiency was transient, however, suggesting that rerouting the entry pathway of viruses alters the expression properties of the viruses.

Changing viral tropism using immunoliposomes alters the stability of gene expression: implications for viral vector design

Many strategies for redirecting the tropism of murine Moloney leukemia virus (MMLV) have been described. Preformed virion-liposome complexes, termed virosomes, have been reported to be relatively stable. Virosomes mediate envelope-independent transduction that allows efficient superinfection of resistant cell lines; however, virosome-mediated transduction behaves in a non-target-specific manner. We developed a novel method using antibodies to direct MMLV to vascular endothelium. We have given the term immunovirosomes to the complexes formed between viruses, liposomes, and antibodies. These immunovirosomes improve the transduction efficiency of the viruses and alter their tropism. We have shown improved transduction when immunovirosomes were targeted at the endocytic receptors CD71 and CD62E/P and rather less good delivery when targeted at CD106. The enhancement of the transduction efficiency was transient, however, suggesting that rerouting the entry pathway of viruses alters the expression properties of the viruses.

Gene delivery to vascular endothelium using chemical vectors: implications for cardiovascular gene therapy

The vascular endothelium is an attractive target for gene therapy because of its accessibility and its importance in the pathophysiology of a wide range of cardiovascular conditions. In general, viral methods have been shown to be very effective at delivering genes to endothelium. The immunogenicity and pathogenicity associated with viral vectors have led increased efforts to seek alternative means of 'ferrying' therapeutic genes to endothelium or to decrease the short-comings of viral vectors. This paper reviews developments in non-viral technology. In addition, discussion also covers the mechanisms whereby existing chemical vectors deliver DNA to cells. Understanding the pathways of vector internalisation and intracellular traffic is important in developing strategies to improve vector technology. The authors propose that the chemical vector may represent a robust and versatile technology to 'ferry' therapeutic genes to vascular endothelium in order to modify the endothelial dysfunction associated with many cardiovascular diseases.

Prevention of postoperative nausea and vomiting after intrathecal morphine for Cesarean section: a randomized comparison of dexamethasone, droperidol, and a combination

BACKGROUND

Intrathecal morphine provides good analgesia after cesarean delivery but the side effects include nausea and vomiting. Low-dose droperidol (0.625 mg) combined with dexamethasone 4 mg is postulated to have an additive antiemetic effect with less side effects. We therefore compared single doses of dexamethasone and droperidol alone with a low-dose combination of the two, to prevent spinal morphine-induced nausea and vomiting after cesarean section.

METHODS

In a double-blind study, 120 women undergoing elective cesarean section under spinal anesthesia (using 0.5% bupivacaine 10 mg and morphine 0.2 mg) were allocated randomly to receive dexamethasone 8 mg, droperidol 1.25 mg, dexamethasone 4 mg and droperidol 0.625 mg, or placebo, before the end of surgery. The incidences of nausea and vomiting, sedative score, pain score, and side effects were recorded.

RESULTS

The incidence of nausea and vomiting within 6 h postoperatively was lower and incidence of no nausea and vomiting for 24 h postoperatively was significantly higher for the combination group compared to the placebo group and the dexamethasone only group. Sedation scores within 3 h postoperatively and incidence of restlessness for the combination group were significantly lower than in the droperidol only group.

CONCLUSION

An additive antiemetic effect and no significant side effects were shown for the combination of dexamethasone 4 mg and droperidol 0.625 mg. This combination was more effective than either dexamethasone 8 mg or droperidol 1.25 mg alone in preventing nausea and vomiting after spinal anesthesia using 0.5% bupivacaine and morphine 0.2 mg.

Preoperative and intraoperative diagnosis of low-grade adenosquamous carcinoma of the breast: potential diagnostic pitfalls

AIMS

Low-grade adenosquamous carcinoma (LGAC), a rare variant of metaplastic breast cancer, may mimic benign or other low-grade malignant lesions histologically. Diagnostic difficulty may be encountered when evaluating breast cytology, core needle biopsy or intraoperative frozen section specimens.

METHODS AND RESULTS

Pathology reports, cytology aspirates and histological slides of LGAC diagnosed at the Department of Pathology, Singapore General Hospital, were reviewed. Four cases of LGAC were analysed. Cytology from the first case showed atypical cells and the subsequent surgical excision specimen showed a complex sclerosing lesion with LGAC. The second and third cases were investigated by core needle biopsies: the preoperative histological features were suggestive of but not diagnostic of LGAC, until further excision biopsies were performed. The fourth case entailed a frozen section specimen, for which definitive diagnosis was deferred to paraffins. The patients remained well with no evidence of recurrent disease to date.

CONCLUSIONS

When limited material, in the form of needle aspirates, core biopsy specimens or frozen sections, is submitted for histology, making a diagnosis of LGAC is not only challenging, but may be impossible. In difficult cases, careful pathological assessment, clinicopathological correlation and follow-up or complete excision biopsy may prove invaluable in establishing a definitive diagnosis.

The Transplantation Society--new key opinion leaders of tomorrow 2006

One of the new initiatives taken by the immediate past president of The Transplantation Society, KJ Wood, is to introduce a new series of meetings named 'New Key Opinion Leaders of Tomorrow'. The Transplantation Society invites the leading young investigators in the field of transplantation to participate in this meeting together with the present leaders of the field. The key objective of this meeting is to identify the potential key opinion leaders of tomorrow. Each presentation during the meeting was jointly given by the senior and junior investigators. The meeting in Buenos Aires covered six main topics on clinical, translational and basic transplantation. These included: innate immunity and inflammation; transplant infectious diseases; tumour and transplantation; medical and ethical aspects of transplantation; dendritic cells (stimulating and manipulating the immune response to a transplant); and ABO incompatible donor recipient pairs. This report focuses on the emerging biological therapeutics and their ramifications on clinical transplantation.

Cytology is useful in breast screening: results and long-term follow-up of the Singapore Breast Screening Pilot Project

OBJECTIVE

The Singapore Breast Screening Pilot Project (SBSPP) was embarked upon (1994-1997) to determine if mammography was useful in early breast cancer detection among Asian women.

PATIENTS AND MEASUREMENTS

Of 28 231 women screened, fine needle aspiration cytology (FNAC) was performed in 232 individuals as part of the triple assessment.

RESULTS

Absolute and complete sensitivities for the diagnosis of carcinoma were 46.7% and 82.2%, respectively, based on the results of FNAC. Specificity was 63.3%. The inadequate rate was 31%. Five women who were considered cancer-free on triple assessment and, in two cases open diagnostic biopsy during the SBSPP, subsequently developed breast cancer after a median follow-up of 6 years.

CONCLUSION

Although our FNAC results compared relatively well with international standards, they reflect a small cohort, and may face additional difficulties in a larger programme.

World Transplant Congress. Boston, Massachusetts, USA, 22-27 July 2006

The World Transplant Congress (WTC) is the first joint international transplant meeting co-organised by the Transplantation Society, the American Society of Transplantation (AST) and the American Society of Transplant Surgeons (ASTS). It was the first meeting of this calibre that was being held by three world-renowned authorities in the field of transplantation. Under the direction of the congress president, AB Cosimi, the attendance of this meeting is a 'must' for all working in the field of transplantation. The congress had provided an important forum for the exchange of new scientific and clinical information that is relevant to solid organ and tissue transplantation. In addition, it also created an arena for the interchange of ideas regarding the care and management of transplant recipients. There were many sessions that were engineered in order to facilitate the discussion of socioeconomic, ethical and regulatory issues related transplantation. On the whole, the meeting has set a very high standard for any future transplant congresses to match-providing the delegates with updates on transplantation with the new scientific prospectives in T cell costimulation, innate immunity (dendritic cells), anatomy of immune response and regulatory T cell biology. More importantly, it has highlighted the potentials of harnessing these new findings for future biological therapies in preventing rejection and inducing tolerance.

Aspirin-treated human DCs up-regulate ILT-3 and induce hyporesponsiveness and regulatory activity in responder T cells

Mature dendritic cells (mDCs) are potent antigen presenting cells, but immature DCs (iDCs) have been shown to have reduced antigen stimulatory capacity. Different strategies have been investigated to augment the tolerogenic capacity of dendritic cells (DCs). We demonstrate that in aspirin-treated human DCs, there is reduced expression of CD1a, HLA-DR and CD86, up-regulation of ILT-3 expression and marginal increases in PDL-1. Aspirin-treated DCs are partially resistant to phenotypic changes following maturational stimuli, such as lipopolysaccharide (LPS) or TNFalpha, IL-1alpha and PGE2. Aspirin-treated DCs demonstrate normal endocytic function, but have a reduced ability to stimulate allogeneic T cells, which is comparable to iDCs. Furthermore, they induce hyporesponsiveness and regulatory activity in responder naïve and memory T cells; for naïve T cells this is achieved more quickly and efficiently than with iDCs. We investigated the mechanism of this regulatory activity and found that both cell-cell contact and inhibitory cytokine activity are involved, although no one cytokine predominates in importance. Blocking ILT-3 or IL-12 does not diminish the capacity of these DCs to induce regulation or Foxp3 expression on the regulatory T cells. Results demonstrate that aspirin-treated DCs display tolerogenic potential, which is of interest in their therapeutic potential in reducing chronic allograft rejection.

Knockdown of mouse VCAM-1 by vector-based siRNA

Graft rejection is critically dependent on the recruitment of leukocytes via adhesion molecules on the endothelium, and inhibition of these interactions can prolong graft survival. We have therefore developed an approach using siRNA to inhibit the expression of VCAM-1 in endothelial cells. We transfected siRNA constructs into murine corneal and vascular endothelium and looked at expression of VCAM-1 and other surface molecules by flow cytometry. Adhesion assays (both static and under flow) were used to determine the effect of VCAM-1 inhibition. The activation of cellular stress responses was assessed by RT-PCR. Constructs encoding siRNA can block expression of VCAM-1 in both corneal and vascular endothelial cells (in the latter case after cytokine stimulation). Inhibition of VCAM-1 expression reduced the ability of T cells to adhere to endothelium. However, there were non-specific effects of siRNA expression, including upregulation of (Programmed Death Ligand 1) PDL1 and decreased cell growth. Analysis of stress pathways showed that the endothelial cells transfected with siRNA had upregulated molecules associated with cell stress. While these data are supportive of a potential therapeutic role for siRNA constructs in blocking the expression of adhesion molecules, they also highlight potential non-specific effects of siRNA that must be carefully considered in any application of this technology.