A Rare Case of Intravascular Papillary Endothelial Hyperplasia of the Hypopharynx: A Case Report and Literature Review.

Intravascular papillary endothelial hyperplasia (IPEH), also known as Masson's hemangioma, is a rare benign vascular lesion characterized by an unusual pattern of endothelial proliferation within a thrombosed vessel. Histologically, IPEH is defined by prominent intraluminal papillary structures composed of a single layer of enlarged endothelial cells, lacking cytologic atypia, mitotic activity, and necrosis. Here, we report a rare case of IPEH identified in the hypopharynx of a 56-year-old male patient, incidentally, on imaging for evaluation of unrelated upper back pain.

Navigating the diagnostic maze: the challenge of sclerosing pneumocytoma in frozen sections.

Pulmonary Sclerosing Pneumocytoma (PSP) represents a rare benign tumor that exhibits a predisposition towards females. Often asymptomatic, its identification usually occurs incidentally through imaging modalities. Histologically, PSP demonstrates features consistent with pneumocytic differentiation and possesses a dual-cell population.

MYOD1 as a prognostic indicator in rhabdomyosarcoma.

Background/objectives: Rhabdomyosarcoma (RMS) is characterized by the expression of the myogenic regulatory protein MYOD1. Histologic types include alveolar, embryonal (ERMS), and spindle cell sclerosing RMS (SRMS). SRMS harbors MYOD1 mutations in a subset of adult cases in association with poor prognosis.

Bi-directional exosome-driven intercommunication between the hepatic niche and cancer cells.

Background: Our understanding of the multiple roles exosomes play during tumor progression is still very poor and the contribution of the normal tissue derived exosomes in distant seeding and tumor outgrowth has also not been widely appreciated.

Methods: Using our all-human liver microphysiological system (MPS) platform as a model to closely recapitulate the early metastatic events, we isolated exosomes from both tumor cells and liver microenvironment.

Results: We observed that while priming of the hepatic niche (HepN) with MDA-231 breast cancer derived exosomes facilitated seeding of the cancer cells in the liver, subsequent tumor outgrowth was diminished; this was consistent with increased entry into dormancy.

Phosphatase PP2A is requisite for the function of regulatory T cells.

Homeostasis of the immune system depends on the proper function of regulatory T cells (T(reg) cells). Compromised suppressive activity of T(reg) cells leads to autoimmune disease and graft rejection and promotes anti-tumor immunity. Here we report a previously unrecognized requirement for the serine-threonine phosphatase PP2A in the function of T(reg) cells.

p53 antagonizes the unfolded protein response and inhibits ground glass hepatocyte development during endoplasmic reticulum stress.

The unfolded protein response (UPR) is triggered during stress of the endoplasmic reticulum (ER) and facilitates tissue homeostasis. Considering the role of p53 tumor suppressor gene in the interpretation of stress-inducing stimuli, in this study, we explored whether p53 modulates UPR. We found that p53 ablation resulted in a profound sensitivity to tunicamycin that was associated with liver dysfunction, ground glass hepatocyte (GGH) development and nuclear atypia/dysplasia.

Growth hormone-releasing hormone receptor splice variant 1 is frequently expressed in oral squamous cell carcinomas.

The expression of growth hormone-releasing hormone (GHRH) splice variant 1 (SV1) receptor in neoplastic lesions of the oral cavity was assessed. The sensitivity of HaCaT keratinocytes to GHRH analogs was also evaluated. Thirty-three benign precancerous oral lesions and 27 squamous cell carcinomas of the oral cavity were evaluated by immunohistochemistry for SV1 expression.

p21/waf1 and smooth-muscle actin α expression in stromal fibroblasts of oral cancers.

Background: Concerted alterations between stromal fibroblasts and neoplastic cells underline the carcinogenic process. Activation of alpha-smooth muscle actin (SMA) expression, a cytoskeleton protein normally expressed only in myoepithelial cells, is considered a landmark for the activation of stromal fibroblasts with little however being known regarding the mechanism governing the expression of SMA in the stroma.

Methods: We have evaluated by immunohistochemistry the expression of SMA in the stroma of oral malignant and pre-malignant lesions, in association with the expression of p53 and p21 tumor suppressors that were shown previously to be deregulated and/or mutated in stromal fibroblasts of various cancers.

p21/waf1 and smooth-muscle actin α expression in stromal fibroblasts of oral cancers.

Background: Concerted alterations between stromal fibroblasts and neoplastic cells underline the carcinogenic process. Activation of alpha-smooth muscle actin (SMA) expression, a cytoskeleton protein normally expressed only in myoepithelial cells, is considered a landmark for the activation of stromal fibroblasts with little however being known regarding the mechanism governing the expression of SMA in the stroma.

Methods: We have evaluated by immunohistochemistry the expression of SMA in the stroma of oral malignant and pre-malignant lesions, in association with the expression of p53 and p21 tumor suppressors that were shown previously to be deregulated and/or mutated in stromal fibroblasts of various cancers.

Acceleration of wound healing by growth hormone-releasing hormone and its agonists.

Despite the well-documented action of growth hormone-releasing hormone (GHRH) on the stimulation of production and release of growth hormone (GH), the effects of GHRH in peripheral tissues are incompletely explored. In this study, we show that GHRH plays a role in wound healing and tissue repair by acting primarily on wound-associated fibroblasts. Mouse embryonic fibroblasts (MEFs) in culture and wound-associated fibroblasts in mice expressed a splice variant of the receptors for GHRH (SV1).