Angioarchitecture of squamous cell carcinoma from hamster buccal pouch: a scanning electron microscopy study

Abstract

Tumoral angiogenesis has been widely studied by histochemical analysis but little has been done regarding morphology of these new vessels. The objective of this study was to perform a qualitative analysis of the angiogenic response to chemical induction with dimethylbenzanthracene (DMBA) and carbamide peroxide of squamous cell carcinoma in pouches of Syrian hamsters after different periods of treatment. Twenty-four Syrian golden hamsters, divided into three groups of eight animals each, had their right jugal pouches treated with a 5% DMBA solution three times a week and a 10% carbamide peroxide two times a week for 55, 70 and 90 days. The left pouch was considered the control. After tumor induction, five animals in each group had their pouches prepared for analysis under scanning electron microscopy and three animals for analysis under light microscopy. The control pouches showed a vascular system composed by few main vessels running parallel to the longest axis of the pouch with some branches. In the pouches submitted to tumor induction, a well-differentiated squamous cell carcinoma was present since 55 days induction in all samples. The new vascular system showed the presence of many tortuous vessels and the majority of them were veins and capillaries. Terminal loops were extremely sinuous adopting a glomerular or corkscrew shape. These tumor vessels are different from normal vessels, presenting irregular diameters, outpouchings and constrictions. Angiogenesis of sprouting and intussusceptive kind could be identified in the tumor pouches, and they were more frequent as the tumor developed.

Sunitinib Improves Some Clinical Aspects and Reverts DMBA-Induced Hyperplasic Lesions in Hamster Buccal Pouch

“…Next to the connective tissue, there is a striated muscle layer mixed with soft connective tissue [21]. This histological characteristic is found in all the control groups (Figure 4).…”

“…To produce the precancerous lesions, we used a protocol that is very similar to other well-described protocols to induce OSCC in HBP [13, 21, 27, 28]. The switch to an angiogenic phenotype in hamster buccal pouch carcinogenic model is a less discrete event that occurs between the third and fifth week after the beginning of the induction protocol [11].…”

“…Oliveira et al [21] showed that, even in the initial phase of tumor induction protocol (55 days and 70 days), a rich new vascular network was formed. This network is necessary to allow tumor growth.…”

Morphological characterization of sprouting and intussusceptive angiogenesis by SEM in oral squamous cell carcinoma

“…In a previous study, we described the angioarchitecture of squamous cell carcinoma in the Syrian hamster cheek pouch (De Oliveira et al ., ). Now we performed a detailed analysis of the structural characteristics of sprouting and IA after 90 days of tumor induction.…”

Induction of neoplastic cells in rat skin

“…It originates from burning agricultural plantations, metallurgical, mineral coal and burning of petroleum products, cigarette smoke, plastics, pesticides and paints. Can still be found in smoked foods, fruits, grains and vegetables, due to atmospheric deposition on them 2 . Biomolecular and epidemiological data suggest an association between sun exposure and skin cancer development.…”