Skip to main content
Download PDF

Immunohistochemical analysis of smooth muscle actin and CD31 in feline post-injection site fibrosarcomas: association with tumour grade, vascular density, and multinucleated giant cells

BMC Veterinary Research volume 21, Article number: 191 (2025) Cite this article

Abstract

Background

Multinucleated giant cells are commonly observed in various malignancies; however their clinical and biological significance remains largely unexplored and it has been hypothesised that the cells may play a role in vascular mimicry, tumour progression and tumour survival. This study aimed to investigate the expression of smooth muscle actin and CD31 in feline post-injection site fibrosarcomas, focusing on relationships between multinucleated giant cells presence, tumour grade, and vascular density to elucidate their potential role in tumour progression.

Results

A total of 61 feline post-injection site fibrosarcomas, histologically graded into grades I, II, and III, were examined immunohistochemically. Smooth muscle actin immunoreactivity was detected in 57/61 (93.4%) cases. Multinucleated giant cells expressing CD31 were identified in 39/61 (63.9%) cases, predominantly in high-grade tumours, with a correlation observed between multinucleated giant cell presence, tumour grade, and mitotic index. Vascular density differed across tumour grades. A negative correlation between vascular density, tumour grade and necrosis score was identified. Additionally, a negative correlation was observed between multinucleated giant cells presence and vascular density.

Conclusions

The findings suggest a complex tumour microenvironment in which multinucleated giant cells and vascular mimicry may facilitate tumour survival under hypoxic conditions, potentially contributing to an aggressive tumour phenotype.

Peer Review reports

Background

Mulitinucleated giant cells (MGCs) have been recognized in various malignancies, including canine and feline mast cell tumours [1, 2], histiocytic sarcoma [3], plasma cell tumour [4], soft-tissue sarcoma, and feline post-injection site sarcoma [5]. Despite being frequently observed in tumours, their clinical and biological significance remains largely unexplored. Macrophages have been identified as the primary precursors of epithelioid cells in vitro, induced to differentiate into these cells by treatment with interleukin 4 (IL-4) [6]. This is significant as a Th2 cytokine environment is commonly linked to the enhanced activation of macrophages and recent studies have confirmed that M2 macrophages can give rise to multinucleated giant cells [7].

In the tumour microenvironment MGCs may represent a senescent cells [8] or can exhibit non–senescent CD31 + immunophenotype [9]. Additionally, these cells might form in response to chronic inflammation which may be associated with the tumour, similar as can be observed in foreign body reaction [10]. This may be supported by the theory that MGCs may form in response to an attempt to eliminate a chronic irritant [11]. Although this seems a logical suggestion, many MGCs, particularly those that are poorly differentiated, are not effective at eradicating neoplasms and are now thought to contribute to tumour progression [12,13,14]. A previous study on human papillary thyroid carcinoma has revealed that MGCs occurrence is associated with advanced malignancy stage and therefore is connected to tumour progression [14].

While MGCs can appear in the context of tumours, their presence is generally not a direct immune mechanism against the malignancies. Instead, they often reflect a complex interaction between the tumour and the immune system, where the MGCs may represent a response to chronic inflammation or be part of the tumour’s microenvironment rather than an active anti-tumour mechanism [11, 14]. Recent studies on human cancer cells have revealed that MGCs are metabolically active and may contribute to tumour heterogeneity and resistance to therapy [15].

Angiogenesis is essential for processes like wound healing; however it can be also seen in pathological conditions such as tumour growth [16]. The process is triggered by growth factors or low oxygen levels, which activate hypoxia-inducible factors [17]. During angiogenesis, previously inactive endothelial cells that line the blood vessels are prompted to proliferate, modify the extracellular matrix, migrate, and differentiate to form the structure of new vessels in response to angiogenic signals [18]. In solid tumours, the vasculature consists of endothelial-lined blood vessels and a non-endothelial microcirculatory network. This non-endothelial network is known as vascular mimicry (VM), and it is thought to arise from the differentiation of cancer stem cells into endothelial-like cells [19].

The aim of the present study was to investigate the expression of immunohistochemical markers, specifically smooth muscle actin (SMA) and CD31, in feline post-injection site fibrosarcomas. Additionally, this study sought to elucidate the relationship between tumour grade, vascular density, and the presence of multinucleated giant cells, with an emphasis on understanding these features and their potential role in tumour progression and aggressiveness.

Results

Histological examination of the tumour samples revealed a distribution across three grades, with 6 tumours classified as grade I (9.8%), 24 as grade II (39.3%), and 31 as grade III (50.8%). In all cases FISS were poorly demarcated, located in the dermis and subcutis. The cells were spindle or polyhedral with marked anisocytosis and anisokaryosis with macronucleosis, and multinucleated giant cells scattered through neoplastic mass. Mitotic count was variable. In most cases various necrotic areas in tumour mass were seen. In all tumours various degree of peripheral mostly perivascular lymphocyte and plasma cell infiltration were seen, also scattered macrophages were seen in tumour mass.

SMA immunolabelling was detected in 93.44% of cases (Fig. 1A). Specifically, SMA expression was observed in 6 grade I tumours (10.53%), 22 grade II tumours (38.6%), and 29 grade III tumours (50.88%). SMA immunolabelling was absent in 4 cases, including 2 grade II tumours (3.28%) and 2 grade III tumours (3.28%).

Fig. 1
figure 1

Feline injection-site fibrosarcoma. (A) Tumour cells show positive expression to SMA. SMA immunostaining with DAB, counterstaining with Mayer’s haematoxylin, 200× (B) Multinucleated giant cell show positive expression to CD31. CD31 immunostaining with DAB, counterstaining with Mayer’s haematoxylin, 400×

Full size image

CD31 immunolabelling was present in multinucleated giant cells in 39 tumours (63.93%) (Fig. 1B). CD31-positive multinucleated giant cells were present in 2 grade I tumours (5.13%), 14 grade II tumours (35.9%), and 23 grade III tumours (58.97%). The mean MGCs count varied across grades, with grade I tumours showing an average of 8 ± 5 cells, grade II tumours showing 15 ± 17 cells, and grade III tumours showing 23 ± 14 cells. Statistical analysis revealed a higher count of multinucleated giant cells in grade III tumours compared to grade II (p = 0.004) and grade I (p = 0.017) (Fig. 2A). Furthermore, a positive correlation was observed between MGCs occurrence and tumour grade (r = 0.49; p = 0.000) (Fig. 2B). Additionally, the presence of MGCs varied between mitotic score (1 vs. 3 p = 0.022; 2 vs. 3 p = 0.02) (Fig. 2C), with a positive correlation between these two parameters (r = 0.441; p = 0.000) (Fig. 2D).

Fig. 2
figure 2

Feline injection-site fibrosarcoma. (A) Mean multinucleated giant cell count in grade I, II, and III tumours. Significantly higher multinucleated giant cell count was observed in grade III tumours compared to grade II (p = 0.004) and grade I (p = 0.017). (B) A positive correlation between multinucleated giant cell occurrence and tumour grade (r = 0.49; p = 0.000). (C) Mean multinucleated giant cell count compared to mitotic score. Significantly higher multinucleated giant cell count was observed in mitotic score 3 compared to mitotic score 1 (p = 0.022) and mitotic score 2 (p = 0.02). (D) A positive correlation between multinucleated giant cell count and mitotic score (r = 0.441; p = 0.000)

Full size image

Vascular density showed a mean value of 21 ± 7 in grade I tumours, 29 ± 11 in grade II, and 17 ± 6 in grade III. Comparative analysis indicated that vascular density was higher in grade II tumours compared to grade III (p = 0.000) (Fig. 3A). Furthermore, a negative correlation was found between vascular density and tumour grade (r=-0.444; p = 0.000) (Fig. 3B). Blood vessel count was highest in with necrosis score 0 and a statistically significant difference was observed between necrosis score 0 vs. 2 (p = 0.005) (Fig. 3C), with a negative correlation (r=-0.411; p = 0.001) (Fig. 3D). Moreover, a negative correlation was found between the MGCs count and vascular density (r=-0.262; p = 0.042) (Fig. 4). Comprehensive tumour characteristics are collected in Supplemental Table 1.

Fig. 3
figure 3

Feline injection-site fibrosarcoma. (A) Mean vascular density in grade I, II, and III tumours. Significantly higher vascular density was in grade II tumours compared to grade III (p = 0.000). (B) A negative correlation between vascular density and tumour grade (r=-0.444; p = 0.000). (C) Vascular density compared to necrosis score. Vascular density was significantly higher in necrosis score 0 compared to necrosis score 2 (p = 0.005). (D) A negative correlation between vascular density and necrosis score (r=-0.411; p = 0.001)

Full size image
Fig. 4
figure 4

A negative correlation between the multinucleated giant cell count and vascular density (r=-0.262; p = 0.042)

Full size image

Discussion

The histological and immunohistochemical findings of this study revealed an important insights into the tumour microenvironment and the progression of feline post-injection site fibrosarcomas. A significant correlation between MGCs presence, tumour grade, and mitotic score was observed. Additionally, the vast majority of evaluated cases were SMA positive, which aligns with previous studies reporting frequent SMA positivity in feline post-injection fibrosarcomas [20, 21].

The presence of MGCs in different tumour grades, with a significant prevalence in grade III tumours, may suggest a potential link between MGCs and tumour aggressiveness. The higher MGCs count in more advanced (grade III) tumours, aligns with previous studies which suggested that MGCs may contribute to tumour progression [22,23,24,25]. In human papillary thyroid carcinoma the presence of MGCs has been associated with advanced malignancy stages [14], supporting the hypothesis that MGCs, although originating from immune cells, may foster a pro-tumorigenic environment [26, 27]. This relationship between MGCs and tumour grade may reflect the immunosuppressive properties often observed in advanced tumours, where MGCs contribute to a Th2-polarized environment that favours tumour growth and immune evasion [28,29,30]. Moreover, a significant association was observed between MGCs occurrence and mitotic score, which further strengthens the potential link between MGCs and aggressive tumour behaviour.

The identification of CD31-positive MGCs in more than half evaluated cases, particularly within higher-grade lesions, suggests an intricate relationship between vascularization and the immune microenvironment in post-injection feline fibrosarcomas. CD31, is known as a well-established endothelial marker and it is widespread used in assessing vascular characteristics in tumours [31], and when expressed on MGCs, may indicate a non-traditional form of vasculature [16, 32]. However, we recognize, that employing CD31 alone does not definitively distinguish vascular mimicry from conventional angiogenesis. Thus, while the detection of CD31‐positive MGCs suggests an endothelial‐like phenotype, these findings should be interpreted with caution. Inclusion of additional markers (e.g., vascular epithelial growth factor, VE-cadherin) and functional assays would ideally provide more robust validation of vascular mimicry [33, 34]. Due to limitations in tissue availability and the scope of the present study, such supplementary analyses were not performed, and therefore our results represent preliminary evidence that warrants further investigation into the role of MGCs in alternative vascular network formation in feline post‐injection site fibrosarcomas.

This phenomenon is in agreement with reports on VM, where non-endothelial cells acquire endothelial-like properties [19, 27]. CD31 expression in MGCs might represent an adaptive response within the tumour microenvironment to support tumour survival and progression under hypoxic conditions. The association between vascular density and tumour grade also reveals complexities in the angiogenic profile of feline post-injection site fibrosarcomas. This finding suggests that high-grade tumours may shift toward alternative mechanisms of nutrient acquisition, such as VM. The increased presence of CD31-positive MGCs in grade III tumours suggests that these cells might participate in the formation of such non-classical vascular channels, thereby facilitating tumour progression and survival within the hypoxic microenvironment characteristic of these aggressive tumours. The adaptation to hypoxia may be driven by the activation of hypoxia-inducible factor-1 (HIF-1), a key regulator of cellular responses to low oxygen levels. Under hypoxic stress conditions, HIF-1 acts as a master regulator by promoting the transcription of numerous genes involved in angiogenesis, metabolic reprogramming, and cellular survival, which are fundamental to cancer development and progression [35, 36]. Such hypoxic conditions may not only stimulate the formation of MGCs but also induce a phenotypic shift in these cells, enabling them to acquire endothelial-like characteristics, thereby contributing to the formation of non-traditional vascular channels that help sustain the tumour despite a reduction in classical blood vessels [37]. This transition is in line with the concept of VM, where tumour cells or associated cells adopt features of endothelial cells to form alternative vascular networks independent of traditional angiogenesis [38]. In our study, high-grade feline post-injection site fibrosarcomas exhibited a paradoxically lower conventional vascular density while simultaneously displaying a significantly higher count of MGCs. Above findings are important in understanding the complex interplay between tumour vascularization and the immune microenvironment. We propose that the lower vascular density in high-grade tumours may reflect a shift towards alternative nutrient acquisition mechanisms, such as VM.

Alternative interpretations of this negative correlation are also plausible. The decreased vascular density in high-grade tumours could result from extensive necrosis and the collapse of normal vasculature, conditions that may further stimulate a compensatory response leading to the recruitment or formation of MGCs. These cells might then participate in VM, serving as a mechanism to bypass the limitations imposed by reduced angiogenesis [38].

Overall, the observed negative correlation underscores the adaptive strategies tumours may employ under hypoxic stress and highlights the potential role of MGCs in facilitating alternative vascularization. Future studies are warranted to further explore these mechanisms, which could ultimately lead to the identification of novel therapeutic targets for managing aggressive malignancies. In human malignancies VM was correlated with high tumour grade, cancer cell invasion, cancer cell metastasis, and reduced survival of cancer [39]. This inverse relationship between vascular density and tumour grade may imply a dynamic vascular remodelling process, where tumours progress toward an increasingly aggressive phenotype by reducing reliance on traditional angiogenesis and adopting alternative vascular strategies. This observation aligns with reports from other malignancies, where declining vascularity accompanies increased necrosis and hypoxia in higher-grade tumours [40]. Elevated levels of HIF-1α, frequently observed in hypoxic tumours or resulting from genetic changes, correlate with poorer patient outcomes across various cancer types [41, 42]. The findings not only highlight the plasticity of the tumour microenvironment but also underscore the potential for MGCs to facilitate tumour survival when conventional angiogenic mechanisms are insufficient. This is noteworthy since as the formation of MGCs in tumours is driven by cellular stress factors such as hypoxia, chemotherapy, radiotherapy, reactive oxygen species production, viral infections, and other factors [27, 43, 44]. Although the exact mechanism underlying MGCs induction remains unclear, other studies point to pathways analogous to those involved in VM [45, 46]. Key processes contributing to MGCs formation are connected with the HIF-1 pathway activation and DNA damage [43, 45].

Furthermore, the association of vascular density with the necrosis score strengthens the link between reduced vascularity and tumour progression. Tumours with high necrosis score exhibit pronounced hypoxic environment, what was previously reported in different malignancy types [42, 47].

The observed positive correlation between MGCs and the mitotic score supports the hypothesis that MGCs could contribute to an environment that promotes cellular proliferation. It is hypothesized that MGCs may secrete various cytokines and growth factors, such as interleukin-6 (IL-6), tumour necrosis factor-alpha (TNF-α), and vascular endothelial growth factor (VEGF), which can modulate the tumour microenvironment and stimulate proliferative signalling pathways. This pro-inflammatory milieu may not only enhance the proliferative capacity of tumour cells but also facilitate further tumour progression and invasion [48]. This association could result from chronic inflammation, which may stimulate both the recruitment of immune cells and the proliferation of tumour cells, contributing to tumour growth and heterogeneity [11]. Moreover, the correlation between MGCs occurrence and tumour grade aligns with the theory, that MGCs not only indicate, but may actively contribute to the malignant progression, potentially by modulating the inflammatory microenvironment or enhancing resistance to immune clearance [27].

Above findings are important in understanding the complex interplay between vascularization and the immune microenvironment in post-injection feline fibrosarcomas. However, a limitation of our study is the absence of comprehensive follow-up data, including parameters such as tumour recurrence, metastasis, and overall survival. Due to limitations in the available follow-up information for the cases studied, we were unable to correlate our histological findings with clinical outcomes. Future studies should aim to incorporate such clinical data to better assess the prognostic significance of these histopathological markers and to enhance the clinical relevance of these observations.

Conclusion

In summary, our study demonstrates that higher-grade feline post-injection site fibrosarcomas exhibit a lower conventional vascular density alongside an increased presence of CD31-positive MGCs. A significant positive correlation between MGC counts and mitotic scores was observed, suggesting that MGCs may be linked to increased cellular proliferation, potentially through alternative vascular mechanisms such as VM. Although the data indicate that MGCs might play a pivotal role in promoting tumour proliferation, the complexity of the tumour microenvironment precludes the identification of a single element as solely responsible for this process. We conclude that MGCs appear to play a special role in tumour proliferation; however, additional studies employing further markers and functional assays are needed to fully elucidate their precise contribution. Overall, our findings highlight the complex interplay between immune, vascular, and stromal components in feline post-injection site fibrosarcomas and underscore the need for further investigation into the roles of MGCs and vascular mimicry in tumour progression. Future studies focusing on the molecular pathways that drive MGC formation and VM could yield valuable insights into therapeutic targets, potentially improving outcomes for feline patients diagnosed with feline post-injection site fibrosarcoma.

Methods

Study design

The study included surgically excised cutaneous tumours collected from 61 cats, 32 (52%) males and 29 (48%) females, aged 4–22 (mean: 12 ± 4 years). The samples were fixed in 10% neutral buffered formalin, processed routinely, embedded in paraffin wax, cut and stained with Mayer’s haematoxylin and eosin (HE). The inclusion criteria included morphological features described previously [49,50,51]. The tumours were located at typical injection sites: flank (34.4%; 21/61 cases), interscapular region (26.2%; 16/61 cases), lumbar area (18%; 11/61 cases), thigh (11.5%; 7/61 cases), dorsal area of the neck (8.2%; 5/61 cases), and shoulder (1.6%; 1/61 cases). Histologically, the tumours were graded into grade I, II and III, according to the grading system proposed by Dobromylskyj et al. [52] for feline soft tissue sarcomas and described previously [51].

Immunohistochemical evaluation

The sections for immunohistochemistry were mounted on silanized glass slides. Heat-induced antigen retrieval was performed in Tris-EDTA buffer pH 9.0 (EnVisionℱ Flex Target Retrieval Solution High pH, DAKO, Glostrup, Denmark) for 20 min at 96 °C using a PT-Link module (Dako, Glostrup, Denmark). Immunohistochemical examination of each tumour was performed using primary antibodies: α-SMA (monoclonal mouse anti-human, clone 1A4, dilution 1:50, incubation time: 30 min in a humid chamber at room temperature; Dako, Glostrup, Denmark) and CD31 (monoclonal mouse anti-human, clone JC70A, dilution 1:20, incubation time: overnight in a humid chamber at 4℃; Dako, Glostrup, Denmark) and a visualisation system based on the immunoperoxidase method, with 3,3-diaminobenzidine (DAB) as a substrate (EnVision + System-HRP, Mouse, Dako, Glostrup, Denmark). The slides were counterstained with Mayer’s haematoxylin. Positive and negative control slides were processed together with the evaluated slides. For the negative control, the primary antibody was replaced by the isotype-matched mouse IgG (Dako) at the appropriate dilution. For the positive control, normal tissues were processed in the similar manner as the evaluated slides (for α-SMA and CD31– feline intestine). Brown precipitate at the antigen site was regarded as a positive reaction. The slides were evaluated under a light microscope (BX63, Olympus, Tokyo, Japan) using CellSense (Olympus, Tokyo, Japan) software.

Vascular density evaluation

Vascular “hot spots” were selected for each tumour under low magnification (×100). Subsequently, vessels were quantified within a 2.37 mm2 area at ×400 magnification. Any brown-stained endothelial cell or endothelial cell cluster that was clearly separated form adjacent microvessels, tumour cells, and surrounding connective tissue was considered as a single, countable vessel. The presence of vessel lumens, though typically observable, was not requisite for microvessel designation, nor was the presence of red blood cells within lumens considered a defining criterion. Mean values (with standard deviation) were calculated for groups with grades I, II and III.

Multinucleated giant cells evaluation

Multinucleated giant cells “hot spots” within tumour parenchyma were selected for each tumour grade under low magnification (×100). Subsequently, the cells were quantified within a 2.37 mm2 area at ×400 magnification. Mean values (with standard deviation) were calculated for groups with grades I, II and III.

Statistical analysis

Differences in vascular density and multinucleated giant cell in groups with grade I, II and III were analysed using Kruskal‒Wallis H test (one-way ANOVA on ranks) followed by Dunn’s post-hoc test. Correlations between tumour grade, MGCs count, vascular density and mitotic index were examined using Spearman’s rank correlation (r: Spearman’s rank correlation coefficient); p ≀ 0.05 was considered statistically significant, and p ≀ 0.001 as highly significant. The statistical analysis was performed using Statistica 14 software (StatSoft Inc., Tulsa, OK, USA).

Data availability

Data used in this study are available from the corresponding author on reasonable request.

References

  1. Sabattini S, Bettini G. Grading cutaneous mast cell tumors in cats. Vet Pathol. 2019;56(1):43–9.

    Article  PubMed  Google Scholar 

  2. de Nardi AB, Dos Santos Horta R, Fonseca-Alves CE, de Paiva FN, Linhares LCM, Firmo BF, et al. Diagnosis, prognosis and treatment of canine cutaneous and subcutaneous mast cell tumors. Cells. 2022;11(4):618.

    Article  PubMed  PubMed Central  Google Scholar 

  3. Mullin C, Clifford CA. Histiocytic sarcoma and hemangiosarcoma update. Vet Clin North Am Small Anim Pract. 2019;49(5):855–79.

    Article  PubMed  Google Scholar 

  4. Hughes KL, Rout ED, Avery PR, Pavuk AA, Avery AC, Moore AR. A series of heterogeneous lymphoproliferative diseases with CD3 and MUM1 co-expressed in cats and dogs. J Vet Diagn Invest. 2023;35(1):22–33.

    Article  CAS  PubMed  Google Scholar 

  5. Dobromylskyj M. Feline soft tissue sarcomas: A review of the classification and histological grading, with comparison to human and canine. Animals. 2022;12(20):2736.

    Article  PubMed  PubMed Central  Google Scholar 

  6. Wang HW, Joyce JA. Alternative activation of tumor-associated macrophages by IL-4: priming for protumoral functions. Cell Cycle. 2010;9(24):4824–35.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  7. Miron RJ, Bosshardt DD. Multinucleated giant cells: good guys or bad guys? Tissue Eng Part B Rev. 2018;24(1):53–65.

    Article  PubMed  Google Scholar 

  8. Bharadwaj D, Mandal M. Senescence in polyploid giant cancer cells: A road that leads to chemoresistance. Cytokine Growth Factor Rev. 2020;52:68–75.

    Article  CAS  PubMed  Google Scholar 

  9. Tan GF, Goh S, Lim AH, Liu W, Lee JY, Rajasegaran V, et al. Bizarre giant cells in human angiosarcoma exhibit chemoresistance and contribute to poor survival outcomes. Cancer Sci. 2021;112(1):397–409.

    Article  CAS  PubMed  Google Scholar 

  10. Al-Maawi S, Wang X, Sader R, Götz W, Motta A, Migliaresi C, et al. Multinucleated giant cells induced by a silk fibroin construct express Proinflammatory agents: an Immunohistological study. Materials. 2021;14(14):4038.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  11. Ahmadzadeh K, Vanoppen M, Rose CD, Matthys P, Wouters CH. Multinucleated giant cells: current insights in phenotype, biological activities, and mechanism of formation. Front Cell Dev Biol. 2022;10:873226.

    Article  PubMed  PubMed Central  Google Scholar 

  12. Rosai J. Liver cell carcinoma with osteoclast-like giant cells: nonepitheliogenic giant cells in diverse malignancies. Hepatology. 1990;12(4 Pt 1):782–3.

    Article  CAS  PubMed  Google Scholar 

  13. Jösten M, Rudolph R. Methods for the differentiation of giant cells in canine and feline neoplasias in paraffin sections. Zentralbl Veterinarmed A. 1997;44(3):159–66.

    Article  PubMed  Google Scholar 

  14. Gulubova MV, Ivanova KV. The expression of Tumor-Associated macrophages and multinucleated giant cells in papillary thyroid carcinoma. Open Access Maced J Med Sci. 2019;7(23):3944–9.

    Article  PubMed  PubMed Central  Google Scholar 

  15. Mirzayans R, Andrais B, Murray D. Roles of polyploid/multinucleated giant Cancer cells in metastasis and disease relapse following anticancer treatment. Cancers. 2018;10(4):118.

    Article  PubMed  PubMed Central  Google Scholar 

  16. Barnett FH, Rosenfeld M, Wood M, Kiosses WB, Usui Y, Marchetti V, et al. Macrophages form functional vascular mimicry channels in vivo. Sci Rep. 2016;6(1):36659.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  17. Lv X, Li J, Zhang C, Hu T, Li S, He S, et al. The role of hypoxia-inducible factors in tumor angiogenesis and cell metabolism. Genes Dis. 2017;4(1):19–24.

    Article  PubMed  Google Scholar 

  18. Potente M, Gerhardt H, Carmeliet P. Basic and therapeutic aspects of angiogenesis. Cell. 2011;146(6):873–87.

    Article  CAS  PubMed  Google Scholar 

  19. Kim HS, Won YJ, Shim JH, Kim HJ, Kim J, Hong HN, et al. Morphological characteristics of vasculogenic mimicry and its correlation with EphA2 expression in gastric adenocarcinoma. Sci Rep. 2019;9(1):3414.

    Article  PubMed  PubMed Central  Google Scholar 

  20. Hendrick MJ, Brooks JJ. Postvaccinal sarcomas in the Cat: histology and immunohistochemistry. Vet Pathol. 1994;31(1):126–9.

    Article  CAS  PubMed  Google Scholar 

  21. Munday JS, Banyay K, Aberdein D, French AF. Development of an injection site sarcoma shortly after meloxicam injection in an unvaccinated Cat. J Feline Med Surg. 2011;13(12):988–91.

    Article  PubMed  PubMed Central  Google Scholar 

  22. Weihua Z, Lin Q, Ramoth AJ, Fan D, Fidler IJ. Formation of solid tumors by a single multinucleated cancer cell. Cancer. 2011;117(17):4092–9.

    Article  PubMed  Google Scholar 

  23. Zhang L, Wu C, Hoffman RM. Prostate Cancer heterogeneous High-Metastatic Multi-Organ-Colonizing Chemo-Resistant variants selected by serial metastatic passage in nude mice are highly enriched for multinucleate giant cells. PLoS ONE. 2015;10(11):e0140721.

    Article  PubMed  PubMed Central  Google Scholar 

  24. Hasegawa K, Suetsugu A, Nakamura M, Matsumoto T, Aoki H, Kunisada T, et al. Imaging the role of multinucleate pancreatic Cancer cells and Cancer-Associated fibroblasts in peritoneal metastasis in mouse models. Anticancer Res. 2017;37(7):3435–40.

    CAS  PubMed  Google Scholar 

  25. Shu Z, Row S, Deng WM, Endoreplication. The good, the bad, and the ugly. Trends Cell Biol. 2018;28(6):465–74.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  26. Kloc M, Uosef A, Subuddhi A, Kubiak JZ, Piprek RP, Ghobrial RM. Giant multinucleated cells in aging and Senescence-An abridgement. Biology. 2022;11(8):1121.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  27. Krotofil M, Tota M, Siednienko J, Donizy P. Emerging paradigms in Cancer metastasis: ghost mitochondria, vasculogenic mimicry, and polyploid giant Cancer cells. Cancers. 2024;16(20):3539.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  28. Anderson S, Shires VL, Wilson RA, Mountford AP. Formation of multinucleated giant cells in the mouse lung is promoted in the absence of interleukin-12. Am J Respir Cell Mol Biol. 1999;20(3):371–8.

    Article  CAS  PubMed  Google Scholar 

  29. Kim SK, Cho SW. The evasion mechanisms of Cancer immunity and drug intervention in the tumor microenvironment. Front Pharmacol. 2022;13:868695.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  30. Hild V, Mellert K, Möller P, Barth TFE. Giant cells of various lesions are characterised by different expression patterns of HLA-Molecules and molecules involved in the cell cycle, bone metabolism, and lineage affiliation: an immunohistochemical study with a review of the literature. Cancers. 2023;15(14):3702.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  31. ran Guo C, Han R, Xue F, Xu L, Ren W, gang, Li M, et al. Expression and clinical significance of CD31, CD34, and CD105 in pulmonary ground glass nodules with different vascular manifestations on CT. Front Oncol. 2022;12:956451.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  32. Jennings RN, Miller MA, Ramos-Vara JA. Comparison of CD34, CD31, and factor VIII-related antigen immunohistochemical expression in feline vascular neoplasms and CD34 expression in feline nonvascular neoplasms. Vet Pathol. 2012;49(3):532–7.

    Article  CAS  PubMed  Google Scholar 

  33. Guzman G, Cotler SJ, Lin AY, Maniotis AJ, Folberg R. A pilot study of vasculogenic mimicry immunohistochemical expression in hepatocellular carcinoma. Arch Pathol Lab Med. 2007;131(12):1776–81.

    Article  PubMed  PubMed Central  Google Scholar 

  34. Wechman SL, Emdad L, Sarkar D, Das SK, Fisher PB. Vascular mimicry: triggers, molecular interactions and in vivo models. Adv Cancer Res. 2020;148:27–67.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  35. Semenza GL. Targeting HIF-1 for cancer therapy. Nat Rev Cancer. 2003;3(10):721–32.

    Article  CAS  PubMed  Google Scholar 

  36. Semenza GL. Hypoxia-Inducible factors in physiology and medicine. Cell. 2012;148(3):399–408.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  37. Maniotis AJ, Folberg R, Hess A, Seftor EA, Gardner LMG, Pe’er J, et al. Vascular channel formation by human melanoma cells in vivo and in vitro: vasculogenic mimicry. Am J Pathol. 1999;155(3):739–52.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  38. Hendrix MJC, Seftor EA, Hess AR, Seftor REB. Vasculogenic mimicry and tumour-cell plasticity: lessons from melanoma. Nat Rev Cancer. 2003;3(6):411–21.

    Article  CAS  PubMed  Google Scholar 

  39. Delgado-Bellido D, Oliver FJ, Vargas Padilla MV, Lobo-Selma L, ChacĂłn-Barrado A, DĂ­az-Martin J, et al. VE-Cadherin in Cancer-Associated angiogenesis: A deceptive strategy of blood vessel formation. Int J Mol Sci. 2023;24(11):9343.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  40. Lugano R, Ramachandran M, Dimberg A. Tumor angiogenesis: causes, consequences, challenges and opportunities. Cell Mol Life Sci. 2020;77(9):1745–70.

    Article  CAS  PubMed  Google Scholar 

  41. Keith B, Johnson RS, Simon MC. HIF1α and HIF2α: sibling rivalry in hypoxic tumor growth and progression. Nat Rev Cancer. 2011;12(1):9–22.

    Article  PubMed  PubMed Central  Google Scholar 

  42. Chen Z, Han F, Du Y, Shi H, Zhou W. Hypoxic microenvironment in cancer: molecular mechanisms and therapeutic interventions. Signal Transduct Target Ther. 2023;8(1):70.

    Article  PubMed  PubMed Central  Google Scholar 

  43. Liu Y, Shi Y, Wu M, Liu J, Wu H, Xu C, et al. Hypoxia-induced polypoid giant cancer cells in glioma promote the transformation of tumor-associated macrophages to a tumor-supportive phenotype. CNS Neurosci Ther. 2022;28(9):1326–38.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  44. Zhou X, Zhou M, Zheng M, Tian S, Yang X, Ning Y, et al. Polyploid giant cancer cells and cancer progression. Front Cell Dev Biol. 2022;10:1017588.

    Article  PubMed  PubMed Central  Google Scholar 

  45. Saini G, Joshi S, Garlapati C, Li H, Kong J, Krishnamurthy J, et al. Polyploid giant cancer cell characterization: new frontiers in predicting response to chemotherapy in breast cancer. Semin Cancer Biol. 2022;81:220–31.

    Article  CAS  PubMed  Google Scholar 

  46. Liu P, Wang L, Yu H. Polyploid giant cancer cells: origin, possible pathways of formation, characteristics, and mechanisms of regulation. Front Cell Dev Biol. 2024;12:1410637.

    Article  PubMed  PubMed Central  Google Scholar 

  47. Nordsmark M, Overgaard J. Tumor hypoxia is independent of hemoglobin and prognostic for loco-regional tumor control after primary radiotherapy in advanced head and neck cancer. Acta Oncol. 2004;43(4):396–403.

    Article  PubMed  Google Scholar 

  48. Coussens LM, Werb Z. Inflammation and cancer. Nature. 2002;420(6917):860–7.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  49. Dean RS, Pfeiffer DU, Adams VJ. The incidence of feline injection site sarcomas in the united Kingdom. BMC Vet Res. 2013;9:17.

    Article  PubMed  PubMed Central  Google Scholar 

  50. Doddy FD, Glickman LT, Glickman NW, Janovitz EB. Feline fibrosarcomas at vaccination sites and non-vaccination sites. J Comp Pathol. 1996;114(2):165–74.

    Article  CAS  PubMed  Google Scholar 

  51. Mikiewicz M, PaĆșdzior-Czapula K, Fiedorowicz J, Gesek M, Otrocka-DomagaƂa I. Metallothionein expression in feline injection site fibrosarcomas. BMC Vet Res. 2023;19(1):42.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  52. Dobromylskyj MJ, Richards V, Smith KC. Prognostic factors and proposed grading system for cutaneous and subcutaneous soft tissue sarcomas in cats, based on a retrospective study. J Feline Med Surg. 2021;23(2):168–74.

    Article  PubMed  Google Scholar 

Download references

Acknowledgements

We would like to thank Dominika Piech and Cezary ZwoliƄski for preparing the archival specimens.

Funding

Project financially supported by the Minister of Science under the Regional Initiative of Excellence Program; the National Science Centre, project No. 2021/05/X/NZ4/00037.

Author information

Authors and Affiliations

  1. Department of Pathological Anatomy, Faculty of Veterinary Medicine, University of Warmia and Mazury in Olsztyn, Oczapowskiego 13 St, Olsztyn, Poland

    Mateusz Mikiewicz & Iwona Otrocka-DomagaƂa

Authors
  1. Mateusz Mikiewicz
    View author publications

    You can also search for this author inPubMed Google Scholar

  2. Iwona Otrocka-DomagaƂa
    View author publications

    You can also search for this author inPubMed Google Scholar

Contributions

MM: writing manuscript, project administration, methodology, investigation, funding acquisition, conceptualization, validation, resources. IO-D: supervision.

Corresponding author

Correspondence to Mateusz Mikiewicz.

Ethics declarations

Consent for publication

Not applicable.

Competing interests

The authors declare no competing interests.

Ethical approval and consent to participate

Ethics approval is not applicable under the Act of 15 January 2015 on the protection of animals used for scientific or educational purposes– Journal of Laws of the Republic of Poland (Journal of Laws 2015 item 266) and Local Ethics Committee for Animal Experiments. The study used archival specimens collected in the Department of Pathological Anatomy. Written informed consent was obtained from the owner or legal custodian of all animals described in this work for the procedures undertaken in this retrospective study. No animals or humans are identifiable within this publication, and therefore additional informed consent for publication was not required.

Additional information

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Electronic Supplementary Material

Below is the link to the electronic supplementary material.

Supplementary Material 1

: Supplementary Table 1. Detailed characteristics of evaluated feline injection-site fibrosarcomas.

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License, which permits any non-commercial use, sharing, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if you modified the licensed material. You do not have permission under this licence to share adapted material derived from this article or parts of it. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc-nd/4.0/.

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Mikiewicz, M., Otrocka-DomagaƂa, I. Immunohistochemical analysis of smooth muscle actin and CD31 in feline post-injection site fibrosarcomas: association with tumour grade, vascular density, and multinucleated giant cells. BMC Vet Res 21, 191 (2025). https://doiorg.publicaciones.saludcastillayleon.es/10.1186/s12917-025-04637-8

Download citation

  • Received:

  • Accepted:

  • Published:

  • DOI: https://doiorg.publicaciones.saludcastillayleon.es/10.1186/s12917-025-04637-8

Keywords

BMC Veterinary Research

ISSN: 1746-6148

Contact us