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Cyclic Changes of Lymphatic Vessels in Human Endometrium  [PDF]
Tatsuo Tomita, Kuni Mah
Open Journal of Pathology (OJPathology) , 2014, DOI: 10.4236/ojpathology.2014.41002

Objective: The presence of lymphatic vessels in endometrium has been controversial and recent immunocytochemical studies with routinely paraffin embedded sections revealed lymphatic vessels in basalis and occasionally in functionalis. We aimed to investigate endometrial lymphatic vessels by immunocytochemical staining using cryosections, which provided better and consistent immunostaining for lymphatic vessels with a lymphatic marker, D2-40. We aimed further to explore the structure-function relationship of lymphatic vessels in the menstrual cycle. Materials and Methods: Sixteen cases of endometrium from menstrual, early-proliferative to latesecretary phase were immunostained for D2-40 and lymphatic vessels were morphometrically analyzed for functionalis, basalis and myometrium, respectively. Results: Lymphatic vessels were consistently most numerous in myometrium, followed by basalis in all phases whereas menstrual endometrium showed small, fragmented aggregates of lymphatic vessels in thin basalis. Earlyto mid-secretary endometrium revealed many lymphatic vessels in basalis and lower-functionalis with few lymphatic vessels in upper-functionalis. Late-secretary endometrium revealed more lymphatic vessels in upper-functionalis with dilated walls, which then burst at the surface of functionalis. Conclusions: These degenerating lymphatic vessels with markedly dilated lumen in upper-functionalis may contribute to lymphatic leakage in late-secretary phase. These immunostained lymphatic vessels in functionalis support proliferating and degenerating lymphatic vessel cycle synchronized with the menstrual cycle of endometrial arteries to maintain adequate fluid leakage.

Tumor-Associated Lymphatic and Venous Vessels in Medullary Thyroid Carcinomas  [PDF]
Tatsuo Tomita
Open Journal of Pathology (OJPathology) , 2015, DOI: 10.4236/ojpathology.2015.52008
Abstract: Objective: Medullary thyroid carcinomas (MTCs) invade local lymph node through lymphatic vessels and metastasize to distant organs hematogenously and account for a significant mortality. There are possibly increased lymphatic and venous vessels, through which the tumor spreads to lymph nodes and distant organs. Materials and Methods: By immunocytochemical staining for lymphatic and venous vessels, MTC lesions with adjacent normal thyroid and both normal and metastatic lymph nodes were studied for the peritumoral lymphatic and venous vessels, which were morphometrically compared with those of normal thyroid and lymph nodes. Sixteen cases of MTC cases with adjacent thyroid tissues and attached lymph nodes were immunocytochemically stained for lymphatic vessels using lymphatic vessel hyaluronan receptor (LYVE-1) and venous vessels for factor VIII (F-8). The immunostained sections of MTC lesions and metastatic lymph nodes were morphometrically compared for the number and sizes of the vessels with those of normal thyroid tissues and lymph nodes. Results: Significantly increased lymphatic vessels and markedly increased blood vessels were identified in many MTC cases at the peritumoral tissues and metastatic lymph nodes whereas a few lymphatic vessels and no venous vessels were identified in midst of MTCs. The irregular peritumoral lymphatic vessels resembled that of immature lymphatic vessels observed in papillary thyroid carcinomas and increased irregularly, entrapped venous vessels in peritumoral tissues resembled those observed in follicular thyroid carcinomas. Conclusion: The significantly increased lymphatic vessels and markedly increased venous vessels in the peritumoral thyroid tissue support a propensity of MTCs for providing an easy access of tumor cells to both lymphatic spread to the regional lymph nodes and venous spread to distant organs with further tumor spread through metastatic lymph nodes by moderately increased lymphatic and venous vessels.
Cancer-Associated Lymphatic and Venous Vessels in Colonic Carcinomas  [PDF]
Tatsuo Tomita
Open Journal of Pathology (OJPathology) , 2014, DOI: 10.4236/ojpathology.2014.43016

Objective: Colonic carcinomas spread to regional lymph nodes and liver. There are cancer-associated lymphatic and venous vessels at the margin of colonic carcinomas, which facilitate spreading carcinoma through lymphatic and venous vessels. This study aimed to examine cancer-associated lymphatic and venous vessels in TNM T1 to T3 carcinomas using lymphatic vessel hyaluronan receptor for lymphatic vessels and von Willebrand factor for venous vessels by immunocytochemical staining. Materials and Methods: A total of 40 cases of moderately differentiated colonic carcinoma were studied using routinely formalin-fixed and paraffin-embedded sections. The cases consisted of 10 cases of TNM T1, 15 cases each of T2 and T3 cases. Immunocytochemical staining was performed using goat antihuman LYVE-1for lymphatic vessels and rabbit antihuman von Willebrand factor for venous vessels. Results: In TNM T1 carcinoma, increased, irregular and narrow lymphatic and venous vessels were present in the adjacent normal mucosa to the carcinoma, some of which penetrated cancerous lesion. There were no tumor emboli in lymphatic and venous vessels. In TNM T2 carcinoma, there were few lymphatic and venous vessels in midst of the carcinoma whereas numerous small lymphatic and venous vessels were present within muscle layers adjacent to the invading carcinoma. Extramural tumor embolus

Follicular thyroid carcinoma invades venous rather than lymphatic vessels
Xiaoqi Lin, Bing Zhu, Yulin Liu, Jan F Silverman
Diagnostic Pathology , 2010, DOI: 10.1186/1746-1596-5-8
Abstract: Follicular thyroid carcinoma (FTC) accounts for 10 - 17% of clinically evident thyroid malignancies [1-4]. It is more common in women, and tends to occur in patients in the fifth decade[1]. Survival is better in women and in patients younger than 40 years for male and 50 years for female [4-6]. Separation of FTC from follicular thyroid adenoma (FTA) is based on detection of vascular and/or capsular invasion[1]. The vascular invasion is almost never evident grossly[7]. Microscopically, the vessels should be located in or immediately outside the capsule (rather than within the tumor), and contain one or more clusters of tumor cells attached to the wall with protrusion into the lumen[1,7]. Often, the intravascular tumor foci are covered by endothelium, in a fashion similar to that of an ordinary thrombus[7]. The endothelial markers, such as CD31, factor VIII-related antigen, and Ulex europaeus, have been used in identifying vascular invasion [8-10]. When vascular invasion is identified in FTCs, there is a prognostic significance based on the number of vessels involved (< 4 or ≥ 4 vascular invasion)[7,11-15].Clinically, FTC tends to spread via blood stream, especially to the bones and lungs, and rarely to regional lymph nodes[1,16-20]. The skeletal metastases are usually multicentric but have a predilection for the shoulder girdle, sternum, skull, and iliac bone[21,22]. These metastases are common in the FTCs demonstrating extensive vascular invasion, but occur in fewer than 5% FTCs with minimal vascular invasion, and develop in less than 1% of the tumors diagnosed as carcinoma only on the basis of minimal capsular invasion[14,23,24]. Thirteen percentage of FTC smaller than 3 cm, 19% FTC between 3 to 6 cm, and 33% FTC > 6 cm show vascular invasion[25]. Up to 10 % of patients with follicular or Hurthle cell carcinoma have tumors that aggressively invade structures in the neck or produce distant metastasis[26]. The metastases may exhibit a better differentiated appearance
Dilated Thin-Walled Blood and Lymphatic Vessels in Human Endometrium: A Potential Role for VEGF-D in Progestin-Induced Break-Through Bleeding  [PDF]
Jacqueline F. Donoghue, C. Jay McGavigan, Fiona L. Lederman, Leonie M. Cann, Lulu Fu, Eva Dimitriadis, Jane E. Girling, Peter A. W. Rogers
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0030916
Abstract: Progestins provide safe, effective and cheap options for contraception as well as the treatment of a variety of gynaecological disorders. Episodes of irregular endometrial bleeding or breakthrough bleeding (BTB) are a major unwanted side effect of progestin treatment, such that BTB is the leading cause for discontinued use of an otherwise effective and popular medication. The cellular mechanisms leading to BTB are poorly understood. In this study, we make the novel finding that the large, dilated, thin walled vessels characteristic of human progestin-treated endometrium include both blood and lymphatic vessels. Increased blood and lymphatic vessel diameter are features of VEGF-D action in other tissues and we show by immunolocalisation and Western blotting that stromal cell decidualisation results in a significant increase in VEGF-D protein production, particularly of the proteolytically processed 21 kD form. Using a NOD/scid mouse model with xenografted human endometrium we were able to show that progestin treatment causes decidualisation, VEGF-D production and endometrial vessel dilation. Our results lead to a novel hypothesis to explain BTB, with stromal cell decidualisation rather than progestin treatment per se being the proposed causative event, and VEGF-D being the proposed effector agent.
Morphogenesis, structure and properties of lymphatic vessels  [PDF]
Anna Ratajska,Ewa Jankowska-Steifer,El?bieta Czarnowska,Aleksandra Flaht
Post?py Higieny i Medycyny Do?wiadczalnej , 2012,
Abstract: In this paper, we present literature results related to structure and various manners of lymphatic vessel formation during embryonic development and in pathological events, such as tumorigenesis, wound healing, and other diseases. The functions of the lymphatic system include the collection of fluids that enter tissues from the circulation, absorption of lipids and lipid-soluble vitamins from the intestine and their subsequent transport, participation in antigen, dendritic cell, and lymphocyte migration. The lymphatic system is also a route for tumor cell and inflammatory cell transport. Native lymphatic capillaries differ from blood capillaries by having an irregular lumen, a discontinuous basement membrane, absence of pericytes, and a strong anchorage of their endothelial cells to the extracellular matrix via microfibrils built of emilin and fibrillin. Lymphatic endothelial cells express surface antigens such as Lyve-1, podoplanin, VEGFR3 (Flk4) and transcription factor Prox-1, as well as molecules which are common for blood endothelial cells and lymphatic endothelial cells (CD31, CD34, Flk-1, Tie-1, Tie-2, neuropilin 2). Lymphatic vessel formation during embryonic development starts with the occurrence of lymphatic sacs sprouting from systemic jugular veins and/or by co-option of lymphangioblasts or hematopoietic-derived cells. It can also proceed by dedifferentiation of venous endothelial cells after their detachment from the venous system, migration to the target places within the body and assembly in the lymphatic lumen. Mechanisms of lymphatic vessel formation during embryonic development and in pathological conditions, such as tumorigenesis, wound healing, and metastasis, is regulated by a plethora of growth factors and molecules, among which the most important are VEGF-C, VEGF-D, HGF, FGF, retinoic acid, IL-3, and IL-7. Macrophages and cells bearing CD45 phenotype seem to take part in the formation of lymphatics. Macrophages might act as a source of growth factors and/or as modulators playing a role in vessel caliber regulation during lymphangiogenesis. We discuss the most important diseases of the lymphatic system, their molecular basis and tumors derived from lymphatic vessels.
Cyclic Changes of Nerve Fibers in Human Endometrium  [PDF]
Tatsuo Tomita, Kuni Mah
Open Journal of Pathology (OJPathology) , 2014, DOI: 10.4236/ojpathology.2014.42011

Objective: The presence of nerve fibers in human endometrium remains unsettled but recent immunocytochemical studies have shown that there was increased innervation in the endometrium from women with endometriosis and some nerve fibers in the normally cycling human endometrium. In the current study, we used uterine tissue cryosections from normal cycling women, which previously provided better immunocytochemical staining for lymphatic vessels than in paraffin sections. Materials and Methods: A total of 16 cases from normally cycling women were included representing menstrual, early proliferative, early to late secretary phase. Neurofilament and CD 56 were used as immunocytochemical markers for nerve fibers with cryosections. Results: There were consistent presence of nerve fibers in myometrium and basalis. Few small nerve fibers were identified in early proliferative endometrium and more nerve fibers were present in lower-half functionalis from mid-secretary phase. Late-secretary functionalis showed less nerve fibers in the upper-half than the lower-half functionalis, implying growing nerve fibers from lower functionalis to upper functionalis in late-secretary phase. Conclusion: Nerve fibers appeared to cyclically grow from basalis to lower functionalis and then from lower functionalis to upper functionalis concomitantly with blood vessels in normally cycling human endometrium. These cycling endometrial nerve fibers consisted mostly of nonmyelinated small nerve fibers, which may transmit pelvic pain in the normally cycling women.

Pathological Steps of Cancer-Related Lymphedema: Histological Changes in the Collecting Lymphatic Vessels after Lymphadenectomy  [PDF]
Makoto Mihara, Hisako Hara, Yohei Hayashi, Mitsunaga Narushima, Takumi Yamamoto, Takeshi Todokoro, Takuya Iida, Naoya Sawamoto, Jun Araki, Kazuki Kikuchi, Noriyuki Murai, Taro Okitsu, Iori Kisu, Isao Koshima
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0041126
Abstract: Introduction To date, an electron microscopy study of the collecting lymphatic vessels has not been conducted to examine the early stages of lymphedema. However, such histological studies could be useful for elucidating the mechanism of lymphedema onset. The aim of this study was to clarify the changes occurring in collecting lymphatic vessels after lymphadenectomy. Methods The study was conducted on 114 specimens from 37 patients who developed lymphedema of the lower limbs after receiving surgical treatment for gynecologic cancers and who consulted the University of Tokyo Hospital and affiliated hospitals from April 2009 to March 2011. Lymphatic vessels that were not needed for lymphatico venous anastomosis surgery were trimmed and subsequently examined using electron microscopy and light microscopy. Results Based on macroscopic findings, the histochemical changes in the collecting lymphatic vessels were defined as follows: normal, ectasis, contraction, and sclerosis type (NECST). In the ectasis type, an increase in endolymphatic pressure was accompanied by a flattening of the lymphatic vessel endothelial cells. In the contraction type, smooth muscle cells were transformed into synthetic cells and promoted the growth of collagen fibers. In the sclerosis type, fibrous elements accounted for the majority of the components, the lymphatic vessels lost their transport and concentrating abilities, and the lumen was either narrowed or completely obstructed. Conclusions The increase in pressure inside the collecting lymphatic vessels after lymphadenectomy was accompanied by histological changes that began before the onset of lymphedema.
Lymphatic vessels assessment in feline mammary tumours
Giuseppe Sarli, Francesco Sassi, Barbara Brunetti, Antonio Rizzo, Laura Diracca, Cinzia Benazzi
BMC Cancer , 2007, DOI: 10.1186/1471-2407-7-7
Abstract: Samples were taken from six normal mammary glands (NMG), ten benign (BT) and 32 malignant (MT) tumours. Immunohistochemical laminin/VEGFR-3 double stain, VEGF-C and CD44 stains were applied to 4 μm-thick sections, and their expression evaluated in intratumoral/extratumoral and intramammary/extramammary fields.All groups revealed a higher number of lymphatics in the extratumoral/extramammary areas. VEGF-C expression in the epithelium paralleled the number of positive vessels in the NMG, BT and MT, whereas VEGF-C higher expression was noted in the intratumoral fields only in infiltrating MT. CD44 score was lower in extratumoral than intratumoral fields in tumours and showed a significant increase in extramammary/extratumoral fields from NMG to MT. Pearson test showed a significant and inversely proportional correlation between CD44 expression and the number of lymphatic vessels with VEGFR-3 in malignant infiltrating tumours.The number of both VEGFR-3 positive and negative lymphatics in the extratumoral and extramammary stroma was significantly higher than intratumoral and intramammary fields respectively in the NMG, BT and MT. This suggests a scant biological importance of intratumoral lymphatics while their higher number is due to the concentration of existing vessels following compression of the extratumoral stroma in spite of a non demonstrable increase from NMG to MT. The tumour model employed provided no evidence of lymphangiogenesis, and metastasis in the regional lymph node develops following the spread through the pre-existing lymphatic network.The lymphatic vessels play a crucial role in a variety of human cancers since tumour cell lymphatic invasion and subsequent development of lymph node metastases significantly influences prognosis. Therefore the lymphatic pathway is an integral part of tumour staging [1].It is well established that for many carcinomas transport of tumour cells via the lymphatics is the most common pattern of initial dissemination. Howeve
An Important Role of Blood and Lymphatic Vessels in Inflammation and Allergy  [PDF]
Silvana Zgraggen,Alexandra M. Ochsenbein,Michael Detmar
Journal of Allergy , 2013, DOI: 10.1155/2013/672381
Abstract: Angiogenesis and lymphangiogenesis, the growth of new vessels from preexisting ones, have received increasing interest due to their role in tumor growth and metastatic spread. However, vascular remodeling, associated with vascular hyperpermeability, is also a key feature of many chronic inflammatory diseases including asthma, atopic dermatitis, psoriasis, and rheumatoid arthritis. The major drivers of angiogenesis and lymphangiogenesis are vascular endothelial growth factor- (VEGF-)A and VEGF-C, activating specific VEGF receptors on the lymphatic and blood vascular endothelium. Recent experimental studies found potent anti-inflammatory responses after targeted inhibition of activated blood vessels in models of chronic inflammatory diseases. Importantly, our recent results indicate that specific activation of lymphatic vessels reduces both acute and chronic skin inflammation. Thus, antiangiogenic and prolymphangiogenic therapies might represent a new approach to treat chronic inflammatory disorders, including those due to chronic allergic inflammation. 1. Introduction According to the World Allergy Organization, allergic disorders affect 30–40% of the world’s population, and the prevalence is escalating to epidemic proportions. Much of the pathology of chronic allergic disorders such as atopic dermatitis and asthma is the long-term result of chronic allergic inflammation at the site of allergen exposure [1]. Thus, to explore additional possibilities to treat chronic allergic disorders, it is of importance to understand the distinct pathomechanisms and properties of chronic inflammation. Inflammation in general is the response of tissues to harmful stimuli such as infectious agents, antigens, or physical and chemical damage. Besides the increased inflammatory cell infiltration into the inflamed tissue, it has become clear in the recent years that acute and chronic inflammatory processes are associated with pronounced vascular remodeling. Angiogenesis and lymphangiogenesis, the growth of new blood vessels and of lymphatic vessels from preexisting ones, are involved in a number of physiological and pathological conditions such as wound healing, tumor growth, and metastatic spread [2–5]. Angiogenesis and lymphangiogenesis also occur in several chronic inflammatory conditions, including rheumatoid arthritis, inflammatory bowel disease, asthma, chronic airway inflammation, atopic dermatitis, and psoriasis [6–9]. Even though blood and lymphatic vessels are key players in acute and chronic inflammatory processes, and thus might serve as new therapeutic targets
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