The extent of cellular heterogeneity in breast cancer could have potential impact on diagnosis and long-term outcome. However, pathology evaluation is limited to biomarker immunohistochemical ...staining and morphology of the bulk cancer. Inter-cellular heterogeneity of biomarkers is not usually assessed. As an initial evaluation of the extent of breast cancer cellular heterogeneity, we conducted quantitative and spatial imaging of Estrogen Receptor (ER), Progesterone Receptor (PR), Epidermal Growth Factor Receptor-2 (HER2), Ki67, TP53, CDKN1A (P21/WAF1), CDKN2A (P16INK4A), CD8 and CD20 of a tissue microarray (TMA) representing subtypes defined by St. Gallen surrogate classification.
Quantitative, single cell-based imaging was conducted using an Immunofluorescence protein multiplexing platform (MxIF) to study protein co-expression signatures and their spatial localization patterns. The range of MxIF intensity values of each protein marker was compared to the respective IHC score for the TMA core. Extent of heterogeneity in spatial neighborhoods was analyzed using co-occurrence matrix and Diversity Index measures.
On the 101 cores from 59 cases studied, diverse expression levels and distributions were observed in MxIF measures of ER and PR among the hormonal receptor-positive tumor cores. As expected, Luminal A-like cancers exhibit higher proportions of cell groups that co-express ER and PR, while Luminal B-like (HER2-negative) cancers were composed of ER+, PR- groups. Proliferating cells defined by Ki67 positivity were mainly found in groups with PR-negative cells. Triple-Negative Breast Cancer (TNBC) exhibited the highest proliferative fraction and incidence of abnormal P53 and P16 expression. Among the tumors exhibiting P53 overexpression by immunohistochemistry, a group of TNBC was found with much higher MxIF-measured P53 signal intensity compared to HER2+, Luminal B-like and other TNBC cases. Densities of CD8 and CD20 cells were highest in HER2+ cancers. Spatial analysis demonstrated variability in heterogeneity in cellular neighborhoods in the cancer and the tumor microenvironment.
Protein marker multiplexing and quantitative image analysis demonstrated marked heterogeneity in protein co-expression signatures and cellular arrangement within each breast cancer subtype. These refined descriptors of biomarker expressions and spatial patterns could be valuable in the development of more informative tools to guide diagnosis and treatment.
We recently established that the elastin-binding protein, which is identical to the spliced variant of β-galactosidase, forms a cell surface-targeted complex with two proteins considered “classic ...lysosomal enzymes”: protective protein/cathepsin A and neuraminidase-1 (Neu1). We also found that cell surface-residing Neu1 can desialylate neighboring microfibrillar glycoproteins and facilitate the deposition of insoluble elastin, which contributes to the maintenance of cellular quiescence. Here we provide evidence that cell surface-residing Neu1 contributes to a novel mechanism that limits cellular proliferation by desialylating cell membrane-residing sialoglycoproteins that directly propagate mitogenic signals. We demonstrated that treatment of cultured human aortic smooth muscle cells (SMCs) with either a sialidase inhibitor or an antibody that blocks Neu1 activity induced significant up-regulation in SMC proliferation in response to fetal bovine serum. Conversely, treatment with Clostridium perfringens neuraminidase (which is highly homologous to Neu1) decreased SMC proliferation, even in cultures that did not deposit elastin. Further, we found that pretreatment of aortic SMCs with exogenous neuraminidase abolished their mitogenic responses to recombinant platelet-derived growth factor (PDGF)-BB and insulin-like growth factor (IGF)-2 and that sialidosis fibroblasts (which are exclusively deficient in Neu1) were more responsive to PDGF-BB and IGF-2 compared with normal fibroblasts. Furthermore, we provide direct evidence that neuraminidase caused the desialylation of both PDGF and IGF-1 receptors and diminished the intracellular signals induced by the mitogenic ligands PDGF-BB and IGF-2.
Progressive proteolytic degradation of cutaneous elastic fibers, that cannot be adequately replaced or repaired by adult dermal fibroblasts, constitutes a major feature of aging skin. Our present ...investigations, employing monolayer cultures of human dermal fibroblasts and organ cultures of skin biopsies, were aimed at testing whether the hydrophilic tannic acid (TA) and lipophilic ellagic acid (EA) would protect dermal elastin from exogenous and endogenous enzymatic degradation. Results from both culture systems indicated that dermal fibroblasts, maintained with TA or EA, deposit significantly more elastic fibers than untreated control cultures despite the fact that neither polyphenol enhanced transcription of elastin mRNA or cellular proliferation. Results of a pulse and chase experiment showed that pretreatment with both polyphenols enhanced biostability of tropoelastin and newly deposited elastin. Results of in vitro assays indicated that both polyphenols bound to purified elastin and significantly decreased its proteolytic degradation by elastolytic enzymes belonging to the serine proteinase, cysteine proteinase, and metallo-proteinase families. Importantly, both polyphenols also synergistically enhanced elastogenesis induced by selected elastogenic compounds in cultures of dermal fibroblasts. We propose that EA and TA may be useful for preventing proteolytic degradation of existing dermal elastic fibers and for enhancing more efficient elastogenesis in aged skin.
The phenotypic resemblance of patients with Costello syndrome and Hurler disease has been linked to impaired formation of elastic fibers that coincides with elevated cellular proliferation. Impaired ...elastogenesis in these diseases associates with respective abnormal accumulation of chondroitin sulfate and dermatan sulfate proteoglycans that induce cell surface shedding of elastin-binding protein (EBP) normally required for intracellular chaperoning of tropoelastin and its assembly into elastic fibers. A variant of the chondroitin sulfate proteoglycan versican, V3, which lacks chondroitin sulfate, has recently been shown to stimulate elastic fiber assembly and decrease proliferation when expressed by retroviral transduction in arterial smooth muscle cells. However, the mechanism(s) by which V3 influences this phenotype is not known. We now demonstrate that transduction of skin fibroblasts from Costello syndrome and Hurler disease patients with cDNA to versican V3 completely reverses impaired elastogenesis and restores normal proliferation of these cells. This phenotypic reversal is accompanied by loss of chondroitin sulfate from the cell surface and increased levels of EBP. Versican V3 transduction of skin fibroblasts from GM
1-gangliosidosis patients, which lack EBP, failed to restore impaired elastogenesis. These results suggest that induction of elastic fiber production by gene transfer of versican V3 in skin fibroblasts is mediated by rescue of the tropoelastin chaperone, EBP.
Clarke G M, Peressotti C, Holloway C M B, Zubovits J T, Liu K & Yaffe M J (2011) Histopathology59, 116–128
Development and evaluation of a robust algorithm for computer‐assisted detection of sentinel ...lymph node micrometastases
Aims: Increasing the sectioning rate for breast sentinel lymph nodes can increase the likelihood of detecting micrometastases. To make serial sectioning feasible, we have developed an algorithm for computer‐assisted detection (CAD) with digitized lymph node sections.
Methods and results: K‐means clustering assigned image pixels to one of four areas in a colourspace (representing tumour, unstained background, counterstained background and microtomy artefacts). Four filters then removed ‘false‐positive’ pixels from the tumour cluster. A set of 43 sections containing tumour (a total of 259 foci) and 59 sections negative for malignancy was defined by two pathologists, using light microscopy, and CAD was applied. For the clinically relevant task of identifying the largest focus in each section (micrometastasis in 22/43 sections), the sensitivity and specificity were 100%. Isolated tumour cells (ITCs) were identified in one slide initially considered to be negative. Identification of all 259 foci yielded sensitivities of 57.5% for ITCs (<0.200 mm), 89.5% for micrometastases, and 100% for larger metastases, with one false‐positive. Reduced sensitivity was ascribed to variable staining. Nine additional metastases (<0.01–0.3 mm) that were not initially identified were detected by CAD.
Conclusions: This algorithm is well suited to the task of sentinel lymph node evaluation and may enhance the detection of occult micrometastases.
Diverse topical products and injectable fillers used for correcting facial wrinkles induce rather short-lived effects because they target replacement of dermal collagen and hyaluronan, matrix ...components of limited biologic durability.
Present studies were aimed at stimulation of fully differentiated human dermal fibroblasts to resume deposition of new extracellular matrix rich of elastin, the most durable and metabolically inert component of dermal ECM.
We have created a novel proteolytic digest of bovine ligamentum nuchae (ProK-60), and tested its potential biological effect on dermal fibroblasts derived from females of different ages. Northern blots, quantitative immunohistochemistry and metabolic assays were used to assess effects of ProK-60 on proliferation and matrix production in primary cultures of dermal fibroblasts, in cultures of skin explants and after implantation of stimulated fibroblasts into the skin of athymic nude mice.
ProK-60 increased proliferation (25–30%) of cultured dermal fibroblasts and significantly enhanced their production of new elastic fibers (>250%) and collagen fibers (100%). These effects were mostly mediated by stimulation of cellular elastin receptor. In contrast, ProK-60 inhibited production of fibronectin (−30%) and chondroitin sulfate proteoglycans (−50%). ProK-60 also activated proliferation of dermal fibroblasts, mostly derived from the
stratum basale and induced deposition of elastic fibers in cultures of skin explants. Moreover, human fibroblasts pre-treated with ProK-60 produced abundant elastic fibers after their injection into the skin of athymic nude mice.
The described biological effects of ProK-60, including its unique elastogenic property, encourage use of this compound in cosmetic formulations stimulating rejuvenation of aged skin.
In this study we evaluate the antifibrotic properties of PG-490-88, a water-soluble derivative of triptolide. Triptolide is an oxygenated diterpene that is derived from a traditional Chinese herb ...that has potent immunosuppressive and antitumor activity. We used the intratracheal bleomycin mouse model and found that PG490-88 inhibits fibrosis in the bleomycin group when given the same day or 5 days after bleomycin. PG490-88 also markedly reduced the number of myofibroblasts in the bleomycin treatment group. An enzyme-linked immunosorbent assay of transforming growth factor (TGF)-β in the bronchoalveolar lavage fluid showed a significant decrease in TGF-β in the PG490-88-treated groups compared to the bleomycin-treated group. Additionally, triptolide blocked bleomycin-induced increase in TGF-β mRNA in cultured normal human lung fibroblasts. The efficacy of PG490-88 when administered late after bleomycin installation suggests a potential role in the treatment of idiopathic pulmonary fibrosis.
Syndecan-1 (CD138), a cell-surface heparan sulfate proteoglycan, is involved in cell–cell, cell-matrix interaction and growth factor binding. Loss of expression of syndecan-1 in tumor cells leads to ...decreased intercellular cohesion, increased potential for tumor invasiveness, and metastatic spread. Furthermore, induction of syndecan-1 expression in the tumor stroma has been postulated to promote tumor angiogenesis via its binding to growth factors such as basic fibroblast growth factor. Although syndecan-1 expression within tumor cells has been investigated in head and neck squamous cell carcinoma, stromal expression has not been studied in detail. We analyzed 38 cases of head and neck squamous cell carcinoma by immunohistochemical staining for syndecan-1 expression within the stroma. The expression of syndecan-1 within tumor cells of various histologic grades of differentiation, squamous cell carcinoma in situ cells, and benign squamous epithelium was also determined. Variable levels of diminished syndecan-1 expression were noted within the dysplastic cells of 9 of 16 (60%) squamous cell carcinoma in situ lesions and in all 38 (100%) invasive squamous cell carcinoma. In general, higher levels of syndecan-1 expression were observed in the well-differentiated tumors, in contrast to significant reduction of expression seen in poorly differentiated tumors. Syndecan-1 expression was observed within the stroma (in fibroblasts) surrounding infiltrating carcinoma cells in 28 of 38 (74%) cases. The intensity of syndecan-1 staining within the stroma showed generally an inverse correlation with the degree of tumor cell differentiation. Syndecan-1 expression was not detected in the stroma beneath normal squamous epithelium or adjacent to areas of squamous cell carcinoma in situ. We conclude that induced expression of syndecan-1 in the stroma surrounding tumor cells of invasive head and neck squamous cell carcinoma is a frequent event. The increased stromal syndecan-1 expression, coupled with its loss from the surface of carcinoma cells, may contribute to tumor cell invasion and the development of metastases.
Abstract
The extent of intra-tumoral heterogeneity - the variation in the composition of cells in a given tumor and those in the local tumor microenvironment - could have potential impact on ...diagnosis, treatment planning and subsequent response to treatment. To evaluate the extent of cancer cellular heterogeneity, we conducted quantitative protein marker multiplex imaging to study the variations in protein marker expression patterns on individual cells and spatial localizations. A multiplexed immunofluorescence imaging platform (MxIF, Cell DIVE) was used to measure the cellular expression of Estrogen Receptor (ER), Progesterone Receptor (PR), Epidermal Growth Factor Receptor 2 (HER2), Ki67, p53, p21WAF1 and p16INK4A in cancer epithelium. Analysis was conducted on a tissue microarray (TMA) representing subtypes classified as Luminal A-like, Luminal B-like (HER2-negative), Luminal B-like (HER2-positive), HER2-positive (non-luminal) or Triple-negative based on tumor grade and immune activity according to the St. Gallen surrogate classification. Of the 101 cores from 59 cases studied, high levels of heterogeneity were observed in ER and PR expression among the hormonal receptor-positive tumors. As expected Luminal A-like cancers exhibited higher proportions of individual cells co-expressing ER and PR, while cells in Luminal B-like, HER2-negative cancers showed ER expression only. Luminal B-like, HER2-positive cores were composed of cells with strong HER2 staining, and some cells co-expressing PR and HER2. Single cells with strong ER and HER2 labelling were rarely observed. Spatial visualizations illustrated that cells with similar expression signatures tend to be clustered together. Among cases which showed p53 overexpression with immunohistochemistry, the overall MxIF-measured p53 level was highest in TNBC compared to HER2+ and Luminal B-like cases. TNBC exhibited the highest proliferative fraction and most incidence of abnormal p53 and p16. We did not observe an association of p21 expression to P53 or P16 patterns, yet a slightly higher proportion of Luminal B-like cancers showed increased P21 levels compared to the other subtypes. Our study demonstrated the application of protein marker multiplexing and quantitative image analysis in measuring heterogeneity of protein co-expression signatures within breast cancer subtypes. Our next step is to apply the methods developed here to study a cohort where molecular profiling and radiomics were conducted (Bayani et al.) to reveal the extent of heterogeneity of breast cancer with a multi-omics approach.
Citation Format: Alison M. Cheung, Dan Wang, Kela Liu, Fiona Ginty, Sharon Nofech-Mozes, Jane Bayani, John M.S. Bartlett, Anne Martel, Martin J. Yaffe. Protein marker heterogeneity in breast cancer subtypes measured using immunofluorescence protein multiplexing and quantitative, single cell image analysis abstract. In: Proceedings of the AACR Virtual Special Conference on Tumor Heterogeneity: From Single Cells to Clinical Impact; 2020 Sep 17-18. Philadelphia (PA): AACR; Cancer Res 2020;80(21 Suppl):Abstract nr PO-084.
Tumour-associated macrophages are linked with poor prognosis and resistance to therapy in Hodgkin lymphoma; however, there are no suitable preclinical models to identify macrophage-targeting ...therapeutics. We used primary human tumours to guide the development of a mimetic cryogel, wherein Hodgkin (but not Non-Hodgkin) lymphoma cells promoted primary human macrophage invasion. In an invasion inhibitor screen, we identified five drug hits that significantly reduced tumour-associated macrophage invasion: marimastat, batimastat, AS1517499, ruxolitinib, and PD-169316. Importantly, ruxolitinib has demonstrated recent success in Hodgkin lymphoma clinical trials. Both ruxolitinib and PD-169316 (a p38 mitogen-activated protein kinase (p38 MAPK) inhibitor) decreased the percent of M2-like macrophages; however, only PD-169316 enhanced the percentage of M1-like macrophages. We validated p38 MAPK as an anti-invasion drug target with five additional drugs using a high-content imaging platform. With our biomimetic cryogel, we modeled macrophage invasion in Hodgkin lymphoma and then used it for target discovery and drug screening, ultimately identifying potential future therapeutics.
•Hodgkin lymphoma cells promote macrophage invasion and an M2-like phenotype.•JAK1/2 inhibitor ruxolitinib decreases Hodgkin lymphoma cell-induced macrophage invasion.•p38 MAPK is identified as a novel target against Hodgkin lymphoma-induced macrophage invasion.•p38 MAPK inhibitor PD-169316 repolarizes macrophages toward an M1-like phenotype.•Hodgkin lymphoma subtype dictates extracellular matrix composition of collagens, fibronectin, and glycosaminoglycans.