Breast carcinomatous tumoral emboli can result from encircling lymphovasculogenesis rather than lymphovascular invasion

Initiation of tumor dormancy by the lymphovascular embolus

Cancer dormancy followed by recurrence remains an enigma in cancer biology. Since both local and systemic recurrences are thought to emanate from dormant micrometastasis which take origin from lymphovascular tumor emboli we wondered whether the process of dormancy might initiate within lymphovascular emboli. This study combines experimental studies with a patient-derived xenograft (PDX) of inflammatory breast cancer (Mary-X) that spontaneously forms spheroids in vitro and budding lymphovascular tumor emboli in vivo with observational studies utilizing tissue microarrays (TMAs) of human breast cancers. In the experimental studies, Mary-X during both lymphovascular emboli formation in vivo and spheroidgenesis in vitro exhibited decreased proliferation, a G0/G1 cell cycle arrest and decreased mTOR signaling. This induction of dormancy required calpain-mediated E-cadherin proteolysis and was mediated by decreased P13K signaling, resulting in decreased mTOR activity. In observational human breast cancer studies, increased E-cadherin immunoreactivity due to increased E-cad/NTF-1 but both decreased Ki-67 and mTOR activity was observed selectively and differentially within the lymphovascular tumor emboli. Both our experimental as well as observational studies indicate that in vivo lymphovascular tumor emboli and their in vitro spheroid equivalent initiate dormancy through these pathways.

Geometric tumor embolic budding characterizes inflammatory breast cancer

PURPOSE

Inflammatory breast cancer (IBC) is characterized by numerous tumor emboli especially within dermal lymphatics. The explanation remains a mystery.

METHODS

This study combines experimental studies with two different IBC xenografts with image algorithmic studies utilizing human tissue microarrays (TMAs) of IBC vs non-IBC cases to support a novel hypothesis to explain IBC's sina qua non signature of florid lymphovascular emboli.

RESULTS

In the human TMAs, compared to tumor features like nuclear grade (size), mitosis and Ki-67 immunoreactivity which show that IBC is only modestly more proliferative with larger nuclei than non-IBC, what really sets IBC apart is the markedly greater number of tumor emboli and distinctly smaller emboli whose numbers indicate geometric or exponential differences between IBC and non-IBC. In the experimental xenograft studies, Mary-X gives rise to tight spheroids in vitro which exhibit dynamic budding into smaller daughter spheroids whereas Karen-X exhibits only loose non-budding aggregates. Furthermore Mary-X emboli also bud dramatically into smaller daughter emboli in vivo. The mechanism that regulates this involves the generation of E-cad/NTF1, a calpain-mediated cleavage 100 kDa product of 120 kDa full length membrane E-cadherin. Inhibiting this calpain-mediated cleavage of E-cadherin by blocking either the calpain site of cleavage (SC) or the site of binding (SB) with specific decapeptides that both penetrate the cell membrane and mimic either the cleavage site or the binding site on E-cadherin, inhibits the generation of E-cad/NTF1 in a dose-dependent manner, reduces spheroid compactness and decreases budding.

CONCLUSION

Since E-cad/NFT1 retains the p120ctn binding site but loses the α-and β-catenin sites, promoting its 360° distribution around the cell's membrane, the vacilating levels of this molecule trigger budding of both the spheroids as well as the emboli. Recurrent and geometric budding of parental emboli into daughter emboli then would account for the plethora of emboli seen in IBC.

Crosstalks Among Cancer Stem Cells and Histopathologic Features in Determining Prognosis in Canine Mammary Gland Carcinomas

The purpose of the present work was the evaluation of the prognostic potential of histopathologic features, cancer stem cells (CSCs), and epthelial-mesenchymal transition (EMT) in relation to lymph node status and lymphovascular invasion (LVI) in canine mammary gland carcinomas (CMGCs). CSCs are proposed as the main cause of tumorigenesis, therapy failure, and recurrence which form a small fraction of tumor bulk. We evaluated presence of micropapillary growth pattern (MGP), infiltration into surrounding tissues (IST), and vasculogenic mimicry (VM) in H&E stained slides of 26 paraffin-embedded tumor samples. Lymph nodes of all cases were assessed. Additionally, they were examined immunohistochemically in terms of vimentin expression as an indicator of EMT which is a well-known mechanism for metastasis, and CD44, CD24, and ALDH1 for CSCs detection. Data analyses showed significant relationships between MGP and CSCs (P = 0.037), VM and CSCs (P = 0.013), lymph node status and CSCs (P = 0.0001), lymph node status and EMT (P = 0.003), IST and LVI (P = 0.05), VM and LVI (P = 0.01), VM and lymph node status (P = 0.007), and LVI and lymph node status (P = 0.04). Results indicated the prognostic value of MGP, VM, and CSCs with respect to confirmed prognostic markers, including LVI and lymph node involvement, in CMGCs.

Lymphovascular Invasion as a Prognostic Factor in Non-Metastatic Adenocarcinoma of Esophagogastric Junction After Radical Surgery

Purpose

Tumors with lymphovascular invasion (LVI) are thought to be associated with lymph node metastasis and to lead to a worse prognosis. However, the effect of LVI on the prognosis of adenocarcinoma of esophagogastric junction (AEG) is still unclear.

Patients and Methods

We retrospectively analyzed 224 consecutive patients with non-metastatic AEG who underwent radical surgery in our hospital from 2004 to 2018. Inverse probability weighting (IPW) analysis was used to eliminate the selection bias. IPW-adjusted Kaplan–Meier curves and Cox proportional hazards models were used to compare disease-specific survival (DSS) and overall survival (OS) between patients with and without LVI.

Results

A total of 224 patients with non-metastatic AEG who underwent radical resection were included in the study and 96 (42.9%) patients developed LVI. Survival analysis showed that LVI were associated with worse DSS (hazard ratio (HR) = 3.12; 95% CI: 1.93–5.03) and worse OS (HR = 2.33; 95% CI: 1.61–3.38). The results were consistent across subgroups stratified by pathologic N stage. Subgroup analysis demonstrated that Siewert type III (HR= 3.20, 95% CI: 1.45–7.06) was associated with worse DSS, but not Siewert type I/II (HR= 1.46, 95% CI: 0.94–2.31, P-interaction=0.047).

Conclusion

LVI are associated with worse prognosis in AEG. LVI had a worse effect on DSS in Siewert type III AEG than Siewert type I/II AEG.

In vitro vascularized tumor platform for modeling tumor-vasculature interactions of inflammatory breast cancer

Inflammatory breast cancer (IBC), a rare form of breast cancer associated with increased angiogenesis and metastasis, is largely driven by tumor-stromal interactions with the vasculature and the extracellular matrix (ECM). However, there is currently a lack of understanding of the role these interactions play in initiation and progression of the disease. In this study, we developed the first three-dimensional, in vitro, vascularized, microfluidic IBC platform to quantify the spatial and temporal dynamics of tumor-vasculature and tumor-ECM interactions specific to IBC. Platforms consisting of collagen type 1 ECM with an endothelialized blood vessel were cultured with IBC cells, MDA-IBC3 (HER2+) or SUM149 (triple negative), and for comparison to non-IBC cells, MDA-MB-231 (triple negative). Acellular collagen platforms with endothelialized blood vessels served as controls. SUM149 and MDA-MB-231 platforms exhibited a significantly (p < .05) higher vessel permeability and decreased endothelial coverage of the vessel lumen compared to the control. Both IBC platforms, MDA-IBC3 and SUM149, expressed higher levels of vascular endothelial growth factor (p < .05) and increased collagen ECM porosity compared to non-IBCMDA-MB-231 (p < .05) and control (p < .01) platforms. Additionally, unique to the MDA-IBC3 platform, we observed progressive sprouting of the endothelium over time resulting in viable vessels with lumen. The newly sprouted vessels encircled clusters of MDA-IBC3 cells replicating a key feature of in vivo IBC. The IBC in vitro vascularized platforms introduced in this study model well-described in vivo and clinical IBC phenotypes and provide an adaptable, high throughput tool for systematically and quantitatively investigating tumor-stromal mechanisms and dynamics of tumor progression.

Tetraploidization of Immortalized Myoblasts Induced by Cell Fusion Drives Myogenic Sarcoma Development with DMD Deletion

Whole-genome doubling is the second most frequent genomic event, after TP53 alterations, in advanced solid tumors and is associated with poor prognosis. Tetraploidization step will lead to aneuploidy and chromosomic rearrangements. The mechanism leading to tetraploid cells is important since endoreplication, abortive cytokinesis and cell fusion could have distinct consequences. Unlike processes based on duplication, cell fusion involves the merging of two different genomes, epigenomes and cellular states. Since it is involved in muscle differentiation, we hypothesized that it could play a role in the oncogenesis of myogenic cancers. Spontaneous hybrids, but not their non-fused immortalized myoblast counterparts they are generated from, induced tumors in mice. Unstable upon fusion, the hybrid genome evolved from initial mitosis to tumors with a highly rearranged genome. This genome remodeling finally produced targeted DMD deletions associated with replicative stress, isoform relocalization and metastatic spreading, exactly as observed in human myogenic sarcomas. In conclusion, these results draw a model of myogenic oncogenesis in which cell fusion and oncogene activation combine to produce pleomorphic aggressive sarcomas.

Inflammatory breast cancer biology: the tumour microenvironment is key

Inflammatory breast cancer (IBC) is a rare and aggressive disease that accounts for ~2-4% of all breast cancers. However, despite its low incidence rate, IBC is responsible for 7-10% of breast cancer-related mortality in Western countries. Thus, the discovery of robust biological targets and the development of more effective therapeutics in IBC are crucial. Despite major international efforts to understand IBC biology, genomic studies have not led to the discovery of distinct biological mechanisms in IBC that can be translated into novel therapeutic strategies. In this Review, we discuss these molecular profiling efforts and highlight other important aspects of IBC biology. We present the intrinsic characteristics of IBC, including stemness, metastatic potential and hormone receptor positivity; the extrinsic features of the IBC tumour microenvironment (TME), including various constituent cell types; and lastly, the communication between these intrinsic and extrinsic components. We summarize the latest perspectives on the key biological features of IBC, with particular emphasis on the TME as an important contributor to the aggressive nature of IBC. On the basis of the current understanding of IBC, we hope to develop the next generation of translational studies, which will lead to much-needed survival improvements in patients with this deadly disease.

Predictors of lymphovascular invasion identified from pathological factors in Chinese patients with breast cancer

This study aimed to evaluate correlations between lymphovascular invasion (LVI) and the expression of estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor-2 (HER-2), Ki-67, CK5/6, epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), E-cadherin, BCL11A and P53 in invasive breast cancer and to identify predictors of LVI based on these pathological factors. In all, 392 paraffin-embedded tissues from consecutive patients with primary operable invasive breast cancer were included. Immunohistochemistry (IHC) was retrospectively performed using a tissue microarray (TMA) of the paraffin-embedded tissues. LVI-positive rates were compared using the χ² test. Correlations between pathological factors were assessed using Spearman's test. Binary logistic regression was employed in multivariate analyses of statistically significant factors. The results showed that LVI positivity was significantly higher in patients with HER-2-positive expression or high Ki-67 expression. HER-2 expression was weakly positively correlated with Ki-67 expression. HER-2-positive expression and high Ki-67 expression were found to be risk factors for LVI, and associations between LVI and other pathological factors were not significant. Therefore, HER-2-positive expression and high Ki-67 expression are predictors of LVI, whereas the expression of ER, PR, CK5/6, EGFR, VEGF, E-cadherin, BCL11A and P53 is not associated with LVI in invasive breast cancer.

Interleukin-30 Promotes Breast Cancer Growth and Progression

The inflammatory tissue microenvironment that promotes the development of breast cancer is not fully understood. Here we report a role for elevated IL30 in supporting the breast cancer cell viability and invasive migration. IL30 was absent in normal mammary ducts, ductules, and acini of histologically normal breast and scanty in the few stromal infiltrating leukocytes. In contrast, IL30 was expressed frequently in breast cancer specimens where it was associated with triple-negative and HER2⁺ molecular subtypes. In stromal leukocytes found in primary tumors or tumor-draining lymph nodes, which included mainly CD14⁺ monocytes, CD68⁺ macrophages, and CD33⁺/CD11b⁺ myeloid cells, IL30 levels increased with disease stage and correlated with recurrence. A negative correlation was determined between IL30 expression by nodal stromal leukocytes and overall survival. In vitro studies showed that human recombinant IL30 upregulated expression of a pro-oncogenic program, including especially IL6 in both triple-negative and HER2⁺ breast cancer cells. In triple-negative breast cancer cells, IL30 boosted a broader program of proliferation, invasive migration, and an inflammatory milieu associated with KISS1-dependent metastasis. Silencing of STAT1/STAT3 signaling hindered the regulation of the primary growth and progression factors in breast cancer cells. IL30 administration in vivo fostered the growth of triple-negative breast cancer by promoting proliferation and vascular dissemination of cancer cells and the accumulation of intratumoral CD11b⁺/Gr1⁺ myeloid cell infiltrates. Overall, our results show how IL30 regulates breast cancer cell viability, migration, and gene expression to promote breast cancer growth and progression and its impact on patient outcome. Cancer Res; 76(21); 6218-29. ©2016 AACR.

Inflammatory breast cancer: unique biological and therapeutic considerations

Through the concerted efforts of many patients, health-care providers, legislators, and other supporters, the past decade has seen the development of the first clinics dedicated to the care of patients with inflammatory breast cancer in the USA and other countries. Together with social networking, advocacy, and education, a few specialised centres have had substantial increases in patient numbers (in some cases ten times higher), which has further expanded the community of science and advocacy and increased the understanding of the disease process. Although inflammatory breast cancer is considered rare, constituting only 2-4% of breast cancer cases, poor prognosis means that patients with the disease account for roughly 10% of breast cancer mortality annually in the USA. I propose that the unique presentation of inflammatory breast cancer might require specific, identifiable changes in the breast parenchyma that occur before the tumour-initiating event. This would make the breast tissue itself a tumour-promoting medium that should be treated as a component of the pathology in multidisciplinary treatment and should be further studied for complementary targets to inhibit the pathobiology that is specific to inflammatory breast cancer.

The presence of extensive retraction clefts in invasive breast carcinomas correlates with lymphatic invasion and nodal metastasis and predicts poor outcome: a prospective validation study of 2742 consecutive cases

We previously reported that the presence of extensive retraction clefts (RC) in breast cancers correlates with increasing tumor size and grade as well as lymphatic tumor spread and predicts poor outcome. This study is a prospective validation of our prior results. Consecutive cases of invasive breast carcinoma (n=2742) were reviewed to determine the diagnoses, including histologic type, grade, presence of lymphovascular invasion (LVI), and extent of RC. No differences were found in the extent of RC between corresponding core needle biopsy and surgical samples. Extent of RC showed a significant correlation with tumor size, grade, LVI, and nodal metastasis in both core needle biopsy and surgical specimens. These associations remained significant in subset analyses of small (≤1 cm), node-negative and node-positive tumors. Extensive RC predicted poor recurrence-free (P<0.0001) and overall (P<0.0001) survival and remained significant in subset analyses of node-negative (P=0.0015 and 0.0021, respectively) and node-positive (P=0.0039 and 0.0214, respectively) cases. Carcinomas without LVI but extensive RC were associated with better outcome than carcinomas with LVI but worse than those without LVI and low RC. This prospective study confirms that the presence of extensive RC in invasive breast carcinomas correlates with aggressive tumor features and lymphatic tumor spread. Extensive RC appears to be an independent factor predictive of poor outcome in node-negative and node-positive disease. Our results support the hypothesis that RCs are the morphologic reflection of biological changes in tumor cells playing a role in lymphatic tumor spread and likely represent an early stage of LVI with similar clinical implications.

The significance of combined CK5/6 and p63 immunohistochemistry in predicting the risks of subsequent carcinoma development in intraductal papilloma of the breast

Prediction of subsequent risks of breast carcinoma (BC) development in intraductal papilloma (IDP) has remained controversial with the exception of atypical papilloma (AP). The potential value of immunohistochemistry (IHC) of cytokeratin 5/6 [CK5/6] and p63 have been proposed but its standardization has also remained controversial. We studied 17 patients initially diagnosed as IDP or AP who subsequently developed BC with 34 age-matched controls. We compared histological features, results of IHC (estrogen receptor [ER], progesterone receptor [PR], human epidermal growth factor receptor 2 [HER2], p63, CK5/6, Ki67), and ultrasound findings. Univariate conditional logistic regression analysis revealed that the status of both CK5/6 and p63/CK5/6 were significantly associated with subsequent BC development (P < 0.05). BC development in CK5/6 positive patients was 17.9% and p63/CK5/6 double positive patients 8.6%, respectively. Ultrasound evaluation was not significantly associated with any of the parameters examined and subsequent carcinoma development. Despite CK5/6 positivity, the subsequent incidence of BC development was nearly 20%. However p63/CK5/6 double positive status could predict a significantly lower subsequent carcinoma incidence, indicating a more accurate prognostic utility. Combining p63/CK5/6 with histological findings could be easily applied and could predict the subsequent BC development of the patients diagnosed as IDP at biopsy.

Clinicopathological significance of 'atypical ductal proliferation' in core needle biopsy of the breast

Atypical ductal proliferation or ADP has been used in histopathological diagnosis of core needle biopsy (CNB) but its details have not been well studied. Therefore, we examined the clinicopathological characteristics of the initial CNB cases diagnosed as 'ADP ' who subsequently turned out to be malignant, and compared the findings to those that did not. Among 101 cases initially diagnosed as ADP in CNB, the second biopsy revealed no carcinoma (38), ductal carcinoma in situ (DCIS) (45) and invasive carcinoma (18). Significant differences were detected between those which turned out to be carcinoma and those that did not, in the status of myoepithelial cells identified by p63 immunohistochemistry (P = 0.026) and ultrasound (US) categories (P < 0.001). We further compared the histopathological characteristics of those initially diagnosed as ADP and subsequently as DCIS or invasive ductal carcinoma (IDC) with those initially diagnosed as such. DCIS or IDC cases initially diagnosed as ADP had significantly lower Ki67 labeling index (P < 0.01, P < 0.01) and histological grade using Van nuys prognostic index (P < 0.01) or Nottingham histological grades (P < 0.01) respectively than those initially as DCIS or IDC. An assessment of myoepithelial components with US findings might contribute to determine the subsequent clinical algorithm of the patients diagnosed as ADP at initial CNB.

Inflammatory breast cancer: New factors contribute to disease etiology: A review

Inflammatory breast cancer (IBC) is a highly metastatic and fatal form of breast cancer. In fact, IBC is characterized by specific morphological, phenotypic, and biological properties that distinguish it from non-IBC. The aggressive behavior of IBC being more common among young women and the low survival rate alarmed researchers to explore the disease biology. Despite the basic and translational studies needed to understand IBC disease biology and identify specific biomarkers, studies are limited by few available IBC cell lines, experimental models, and paucity of patient samples. Above all, in the last decade, researchers were able to identify new factors that may play a crucial role in IBC progression. Among identified factors are cytokines, chemokines, growth factors, and proteases. In addition, viral infection was also suggested to participate in the etiology of IBC disease. In this review, we present novel factors suggested by different studies to contribute to the etiology of IBC and the proposed new therapeutic insights.

The membrane-cytoskeletal protein 4.1N is involved in the process of cell adhesion, migration and invasion of breast cancer cells

Protein 4.1N belongs to the protein 4.1 superfamily that links transmembrane proteins to the actin cytoskeleton. Recent evidence has shown that protein 4.1 is important in tumor suppression. However, the functions of 4.1N in the metastasis of breast cancer are largely unknown. In the present study, MCF-7, T-47D and MDA-MB-231 breast cancer cell lines with various metastatic abilities were employed. Protein 4.1N was found to be expressed in poorly metastatic MCF-7 and middle metastatic T-47D cell lines, and was predominantly associated with cell-cell junctions. However, no 4.1N expression was detected in the highly metastatic MDA-MB-231 cells. Moreover, re-expression of 4.1N in MDA-MB-231 cells inhibited cell adhesion, migration and invasion. The results suggest that protein 4.1N is a negative regulator of cell metastasis in breast cancer.

Tumor-selective, adenoviral-mediated GFP genetic labeling of human cancer in the live mouse reports future recurrence after resection

We have previously developed a telomerase-specific replicating adenovirus expressing GFP (OBP-401), which can selectively label tumors in vivo with GFP. Intraperitoneal (i.p.) injection of OBP-401 specifically labeled peritoneal tumors with GFP, enabling fluorescence visualization of the disseminated disease and real-time fluorescence surgical navigation. However, the technical problems with removing all cancer cells still remain, even with fluorescence-guided surgery. In this study, we report imaging of tumor recurrence after fluorescence-guided surgery of tumors labeled in vivo with the telomerase-dependent, GFP-containing adenovirus OBP-401.. Recurrent tumor nodules brightly expressed GFP, indicating that initial OBP-401-GFP labeling of peritoneal disease was genetically stable, such that proliferating residual cancer cells still express GFP. In situ tumor labeling with a genetic reporter has important advantages over antibody and other non-genetic labeling of tumors, since residual disease remains labeled during recurrence and can be further resected under fluorescence guidance.