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Grace Guzman

Publications and source records attributed to Grace Guzman.

12 recordsLinked to original sources
PubMed2006

The deficiency of Akt1 is sufficient to suppress tumor development in Pten+/- mice.

The tumor suppressor PTEN is frequently inactivated in human cancers. A major downstream effector of PTEN is Akt, which is hyperactivated via PTEN inactivation. It is not known, however, whether diminished Akt activity is sufficient to inhibit tumorigenesis initiated by Pten deficiency. Here we showed that the deficiency of Akt1 is sufficient to dramatically inhibit tumor development in Pten+/- mice. Akt1 deficiency had a profound effect on endometrium and prostate neoplasia, two types of human cancer, in which PTEN is frequently mutated, and also affected thyroid and adrenal medulla tumors and intestinal polyps. Even haplodeficiency of Akt1 was sufficient to markedly attenuate the development of high-grade prostate intraepithelial neoplasia (PIN) and endometrial carcinoma. These results have significant implications for cancer therapy.

Adrenal Gland Neoplasms↗
PubMed2006

Alpha-methylacyl-CoA racemase (AMACR/P504S) can distinguish hepatocellular carcinoma and dysplastic hepatocytes from benign nondysplastic hepatocytes.

Immunohistochemical staining with alpha-methylacyl-CoA racemase AMACR (P504S) has been described in a number of normal tissues and was found to be useful for detecting malignancies including hepatocellular carcinoma (HCC). Our aim was to determine whether AMACR is differentially expressed in benign nondysplastic liver tissue, hepatocellular dysplasia, and HCC. The study material consisted of paraffin blocks containing primary HCC and surrounding liver tissue from 20 patients who underwent hepatectomy at the time of liver transplantation. Immunohistochemical stains were performed with anti-AMACR by standard methods. Staining features were characterized on the basis of the pattern and distribution of reactivity. A positive AMACR immunostain was defined as either finely stippled or coarsely granular in pattern, in a diffuse or parabasal cytoplasmic distribution. A negative AMACR immunostain was defined as absence of reactivity. Anti-AMACR immunostains were positive in malignant, dysplastic, and benign nondyplastic hepatocytes in all cases. The staining pattern was the same in malignant and dysplastic hepatocytes. It consisted of coarsely granular reactivity in a parabasal or diffuse cytoplasmic distribution. In contrast, benign nondysplastic hepatocytes were distinguished by weak, finely stippled diffuse cytoplasmic staining. Malignant and dysplastic hepatocytes showed an identical pattern of immunostaining for AMACR that was distinct from benign hepatocytes. Prospective studies are needed to determine whether staining for AMACR can distinguish HCC or dysplasia in cytologic and small histologic specimens.

Carcinoma, Hepatocellular↗
PubMed2006

Nectin-1 expression in the normal and neoplastic human uterine cervix.

CONTEXT: Nectin-1 is an immunoglobulin-like adhesion molecule that is widely expressed in epithelial tissues and participates in the formation of adherens junctions. Reduced expression of nectin-1 has been reported in invasive carcinomas of the human skin. OBJECTIVE: To determine the pattern of nectin-1 expression in the normal, dysplastic, and neoplastic human uterine cervix. DESIGN: This retrospective study was performed using immunohistochemistry of specimens of normal mucosa (n = 18) and preneoplastic and neoplastic conditions of the human uterine cervix including squamous dysplasia and invasive uterine cervical squamous carcinoma (n = 23). All specimens were graded according to intensity of cytoplasmic staining (0 = no staining; 4 = strongest intensity). RESULTS: Strong widespread cytoplasmic nectin-1 reactivity was found in normal uterine cervical squamous and endocervical mucosa (mean grade = 2.63). In contrast, uterine cervical and endocervical stroma showed minimal to absent staining (mean grade = 0.58). There was a significant difference in staining intensity between normal mucosa versus stroma (P < .001, Wilcoxon matched pairs- signed ranks test). All squamous dysplasia and carcinoma specimens displayed strong cytoplasmic nectin-1 staining (mean grade = 3.08). The advancing edge of these carcinomas demonstrated significantly decreased or absent expression of nectin-1 (mean grade = 1.39) with significant difference in staining intensity at the center of invasive tumors versus the advancing edge (P = .004, Wilcoxon matched pairs-signed ranks test). CONCLUSIONS: Normal squamous mucosa, dysplasia, and invasive carcinomas of the human uterine cervix stain strongly with nectin-1, and this staining is reduced or absent in the advancing edge of invasive tumors. These findings suggest that down-regulation of nectin-1 may be associated with the loss of cell-to-cell adhesion at the advancing edge of invasive squamous carcinomas of the human uterine cervix.

Biomarkers, Tumor↗
PubMed2005

p53, Ki-67, and serum alpha feto-protein as predictors of hepatocellular carcinoma recurrence in liver transplant patients.

Patients with hepatocellular carcinoma who undergo orthotopic liver transplantation (OLT) are at risk for post-transplant tumor recurrence. The aim of this study was to evaluate whether expression of p53 and Ki-67 in hepatocellular carcinoma lesions present in explanted liver tissue was associated with time to tumor recurrence after OLT. Subjects consisted of 20 consecutive patients who underwent OLT and were found to have hepatocellular carcinoma in the liver explant. Immunostaining for p53 and Ki-67 was performed by standard methods. The presence of nuclear immunostaining in >10% of the tumor tissue was considered positive. Time to recurrence of hepatocellular carcinoma after OLT was compared between patients with positive and negative immunostaining by the log rank test. Multivariate analysis was performed using a Cox regression model to control for potentially confounding clinical factors. Time to post-transplant hepatocellular carcinoma recurrence was significantly more rapid in p53+ (P=0.0007) and Ki-67+ cases (P=0.001). These associations remained significant in multivariate analysis. Furthermore, time to recurrent hepatocellular carcinoma was significantly shorter in patients with a serum alpha feto-protein (AFP) level >or=100 ng/ml at time of diagnosis, compared to those with an AFP level <100 ng/ml (P=0.003). In conclusion, expression of p53 and Ki-67 in hepatocellular carcinoma lesions, and a serum AFP level >or=100 ng/ml were associated with more rapid recurrence of hepatocellular carcinoma after OLT. Identification of patients at risk for early post-transplant recurrence could be used to guide surveillance and adjuvant treatment strategies.

Biomarkers, Tumor↗
PubMed2005

High-grade pelvic osteosarcoma with intravascular extension to the right side of the heart: a case report and review of the literature.

We describe a rare case of high-grade osteosarcoma with intravascular extension to the right atrium and right ventricle in a 23-year-old woman. Osteosarcomas rarely metastasize to the heart, and only a few cases have been reported in the literature thus far. Diagnoses in some of these cases were made during investigation for severe cardiac failure and in most of these cases at autopsy. We describe a unique case of intravascular extension of the tumor embolus in a cordlike fashion from the left femoral vein to the right side of the heart that morphologically resembled a chondrosarcoma.

Adult↗
PubMed2004

Glossal angiomyoma: imaging findings and endovascular treatment.

BACKGROUND: An angiomyoma is an uncommon, benign tumor characterized by numerous vascular channels intermixed with bundles of smooth muscle cells. Oral manifestations are quite rare. We describe for the first time the CT, MRI, and angiographic imaging features and successful preoperative endovascular embolization of an angiomyoma of the tongue. The pathologic findings before and after embolization are also described. METHODS AND RESULTS: A 25-year-old man was seen with a rapidly enlarging tongue mass. Imaging studies revealed the extent and hypervascular nature of this tumor. The diagnosis of angiomyoma was confirmed by histologic examination. Preoperative embolization proved to be helpful in the surgical management of this lesion. CONCLUSIONS: Angiomyoma should be considered in the differential diagnosis of any well-circumscribed, hypervascular, soft tissue tumor in the mouth. In addition, endovascular embolization may be a useful adjunct that facilitates resection.

Adult↗
PubMed2004

Clear cell sarcoma: an institutional review.

Clear cell sarcoma of the tendons and aponeuroses (CCSTA) is an aggressive, rare soft-tissue tumor representing approximately 1 per cent of all soft tissue sarcomas. Although it appears to be histogenetically related to melanoma, its clinical behavior resembles soft tissue sarcoma with a propensity for lymph node metastases. We report our experience at a tertiary referral center. Eight cases of CCSTA evaluated at the University of Illinois at Chicago's Medical Center between 1980 and 2002 were retrospectively reviewed. Patient data analyzed included age, gender, anatomic location, size of tumor, development of local, regional, and distant recurrence, and patient status at last follow-up. Local recurrence did not develop in any patient. Metastases developed in three patients with median time to presentation of metastases of 23 months (range, 8-36 months) from the time of initial diagnosis. Two of these three patients died of their disease with an average interval until death of 22 months from the time of initial diagnosis. The disease-free 2- and 5-year survivals were 68 per cent and 50 per cent, respectively. The overall 2- and 5-year survivals were 86 per cent and 68 per cent, respectively. CCSTA is an aggressive tumor of the soft tissues. These tumors present a high risk for development of distant disease and therefore warrant aggressive surgical management and treatment. Neither aggressive multiagent chemotherapy nor radiotherapy appeared to have an impact on outcome.

Adult↗