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K L Chang

Publications and source records attributed to K L Chang.

At least 55 records · Page 3Linked to original sources
PubMed1997

The effect of decalcification on in situ hybridization.

In situ hybridization (ISH) for mRNA polyadenylated sequences was performed on 25 non-neoplastic and neoplastic decalcified, paraffin-embedded tissues using a poly d(T) oligonucleotide probe to assess the efficacy of this molecular diagnostic tool on decalcified tissue samples. Three commercially available decalcifying agents were used, including one EDTA-based solution (Versenate) and two hydrochloric acid-based solutions (S/P Decal, RBD). Before decalcification, the tissues were fixed in formalin for 6, 24, and 72 hours, respectively. The results of ISH performed on decalcified tissues were compared with the results from the nondecalcified control samples for each tissue using a numeric scoring system (0, negative; 4, strong positivity equal to control; 5, stronger than control). There was generally excellent reactivity when using Versenate (mean, 4.15), good reactivity with S/P Decal (mean, 3.17), and fair-to-poor reactivity with RBD (mean, 1.69) (all P values < .0001). The length of time in formalin did not affect the outcome of ISH on these tissues. We conclude that ISH can be performed with success on decalcified, paraffin-embedded tissues when using Versenate, an EDTA-based agent. Although accurate results might be obtained with S/P Decal and RBD, caution should be exercised when using these two hydrochloric acid-based solutions because they might produce false-negative results.

Chelating Agents↗
PubMed1997

Correlation of interleukin-1 beta, interleukin-6, and periodontitis.

In order to understand the role of IL-1 beta and IL-6 in the periodontal tissue destruction coincident to periodontitis, we assessed the levels of these two mediators in both the gingival tissue and the serum of patients with periodontal disease and of periodontally healthy subjects. In addition, production of IL-6 by six healthy human gingival fibroblast (HGF) strains in response to IL-1 beta was also investigated. The levels of IL-1 beta and IL-6 in gingival tissues and in serum were examined by ELISA. Both mediators were observed to increase in diseased tissues of patients with adult periodontitis, and there was a positively significant relationship between both mediators and clinical assessments of periodontal destruction. Moreover, a significant correlation was also noted between levels of IL-1 beta and IL-6 in gingival tissues of periodontitis patients (r = 0.4334, p < 0.01). However, there was no significant difference in the serum levels of IL-1 beta and IL-6 between periodontitis patients and periodontally healthy controls. In fibroblast cultures, confluent monolayers of HGF were incubated with recombinant human IL-1 beta for 48 h at 37 degrees C in 5% CO2 and air. At the end of the culture period, supernatants were collected and assayed for IL-6 activity by inducing proliferation in the IL-6-dependent hybridoma cell line 7TD1. A dose-dependent stimulatory effect of IL-1 beta on IL-6 production by HGF was noted, wherein 3 strains exhibited higher IL-6 activity than the other 3. These data indicate that the levels of IL-1 beta and IL-6 in gingival tissues are closely related to the severity of periodontal disease and that the IL-1 beta and IL-6 produced in gingival tissues may not reflect these two mediators levels in serum. Moreover, IL-1 beta responsiveness of HGF in IL-6 production depends on both the concentration of IL-1 beta and cells of individual subjects. Since HGF are present in periodontal lesion, it is possible that IL-6 secretion stimulated by exposure to inflammatory cell products such as IL-1 beta may participate in the destruction of periodontal tissue in periodontitis.

Adult↗
PubMed1997

Clonality in lymphocyte predominance Hodgkin's disease.

Abundant evidence has led to the clinical and biological separation of lymphocyte predominance from other types of Hodgkin's disease. However, it is still not clear whether lymphocyte predominance represents a polyclonal reactive lesion (possibly representing an abnormal immune disorder), a polyclonal or oligoclonal preneoplastic disorder or a monoclonal neoplastic disorder. The clinical and histological features are distinctive, but they do not provide clear indications of the nature of lymphocyte predominance. Some immunohistochemical and in situ hybridization studies have shown monotypic light chain restriction in the L&H cells, almost always of kappa type, implying a monoclonal process. Southern blotting studies are of limited utility, given their relatively low sensitivity and the rarity of L&H cells within involved tissues. Polymerase chain reaction studies have yielded conflicting results. Some, but not all, have demonstrated monoclonal populations in tissue extracts. Single cell PCR studies have generally not found monoclonal populations, although one case stands as an exception. Cases of large cell lymphoma complicating lymphocyte predominance have been monoclonal by polymerase chain reaction and clonospecific primers derived from these clones have demonstrated similar populations in the corresponding lymphocyte predominance tissues in some, but not all, studies.

Blotting, Southern↗
PubMed1996

The association of the Epstein-Barr virus with malignant lymphoma.

The Epstein-Barr virus, a human herpesvirus, has been found in the neoplastic cells of numerous lymphoid malignancies, including Burkitt's lymphoma, immunodeficiency-associated lymphoproliferative disorders, nasal T/NK lymphoma, and Hodgkin's disease. The available data suggest that Epstein-Barr virus contributes to the pathogenesis of many of these neoplasms but is not directly linked to the etiology of any of these lymphomas.

Herpesvirus 4, Human↗
PubMed1996

Low-energy helium-neon laser irradiation stimulates interleukin-1 alpha and interleukin-8 release from cultured human keratinocytes.

Clinical observations have suggested that low-energy lasers might promote wound healing. Evidence suggests that He-Ne laser irradiation induces an increase in the rate of keratinocyte migration and proliferation as compared with nonirradiated controls in vitro. This study sought to determine whether He-Ne laser could induce cytokine production in cultured keratinocytes. The results revealed (i) a significant increase in interleukin-1 alpha and interleukin-8 production and their respective mRNA expression in He-Ne laser-treated groups as compared with nonirradiated controls, and (ii) under 1.5 joules/cm2 irradiation, this stimulating effect of He-Ne laser treatment is concentration-dependent. Because interleukin-1 alpha induces keratinocyte migration, this finding may partially explain the stimulatory effects on the motility of keratinocytes. As both interleukin-1 alpha and interleukin-8 provoke proliferation of keratinocytes, it is not unreasonable to propose that these two cytokines play a profound role in the enhancement of keratinocyte proliferation as a result of He-Ne laser irradiation. Our findings provide further evidence of enhanced wound healing at the cellular and molecular level as a result of the He-Ne laser.

Cells, Cultured↗
PubMed1995

Immunohistochemical analysis of T cell phenotypes in patients with graft-versus-host disease following allogeneic bone marrow transplantation.

Allogeneic bone marrow transplantation has become the therapy of choice in many cases of hematologic malignancy. In both matched related donor transplants--and, to a greater degree, in unrelated donor transplant situations--a major complication of the procedure is GVHD. This problem is caused by mature T cells in the graft, which also facilitate engraftment, and mediate an antitumor effect to reduce relapse. In order to further characterize the T cells that are present at the GVHD site of injury, we have studied 134 fresh tissue biopsies using immunohistochemical methods from 50 consecutive ABMT recipients clinically suspected of having acute GVHD. Antibodies specific for T cells, T cell receptor subsets, B cells, and NK cells were used to characterize the lymphocytic infiltrate in the biopsy tissue from GVHD patients. The data showed that the majority of lymphocytes that had infiltrated the epithelium or epidermis were CD3+ T cells. Using antibodies that distinguished the alpha/beta (beta F1) from the gamma/delta TCR (TCR delta 1)-expressing T cells, we observed that the lymphocytic infiltrates from involved tissues of the gastrointestinal tract, skin, and liver are almost exclusively derived from the alpha/beta expressing T cell subset, and are of the memory cell subset of T cells (CD45RO). This is in contrast to some examples from other disease states, in which a significant proportion of the lymphocytes that infiltrate the epidermal layers are of the gamma/delta type.

Adolescent↗
PubMed1995

Infrequent association of Epstein-Barr virus with CD30-positive anaplastic large cell lymphomas from American and Asian patients.

CD30 (Ki-1)-positive anaplastic large cell lymphoma (CD30+ ALCL) is a morphologically and immunophenotypically distinct subset of non-Hodgkin's lymphoma. Although the presence of Epstein-Barr virus (EBV) has been well documented in a significant proportion of cases of Hodgkin's disease, another CD30+ malignancy, few studies have examined the association of EBV with CD30+ ALCL. These latter studies have produced conflicting findings. To further investigate the existence of a putative association of EBV with CD30+ ALCL, and whether this association, if present, shows geographic variation, we examined 34 formalin-fixed, paraffin-embedded specimens from cases of CD30+ ALCL from the United States and Hong Kong. Immunophenotypically, 15 cases were of B lineage, 15 cases were of T lineage, one case expressed both B- and T-cell markers, and three were of null lineage. A highly sensitive in situ hybridization method was performed with use of an antisense oligonucleotide probe to the EBV-encoded RNA (EBER-1). EBV-RNA was identified in 3 of 14 CD30+ ALCL specimens from Hong Kong patients and in 1 of 20 from the American patients. The EBER-1 signal was present in all or virtually all of the tumor cell nuclei in the three EBV-RNA-positive CD30+ ALCL Hong Kong cases, but was only focally present in the single EBV-positive American case. The latent membrane protein-1 (LMP1) of EBV was identified in only one of the four positive cases, a Hong Kong case. Our results suggest that in contrast to Hodgkin's disease, EBV has no significant association with CD30+ ALCL.

Adolescent↗
PubMed1995

Pathologic features of nodular lymphocyte predominance Hodgkin's disease in extranodal sites.

We describe the gross and histologic features of nodular lymphocyte predominance Hodgkin's disease (NLPHD) occurring in extranodal sites. Fifty-one specimens of NLPHD from 16 patients were studied. The sites of involvement were the spleen, liver, tonsil, salivary glands, skin, colon, soft tissue, and bone marrow, and the morphologic features were similar to those described in node-based NLPHD, including characteristic lymphocytic and/or histiocytic (L&H) cells that were easily identified in a background of a nodular proliferation of small lymphocytes and histiocytes. In the spleen, the normal architecture was generally preserved, and the tumor was found predominantly in the white pulp; the red pulp was rarely involved. In the liver, the tumor involved both the portal and parenchymal areas. In the tonsil, the lympohproliferation closely resembled the typical appearance of NLPHD in a lymph node. In all specimens with materials available for immunohistochemical studies, there were demonstrable L&H cells with an immunophenotype similar to node-based NLPHD, that is, CD45-positive, CD20-positive, and CD15-negative. The unique morphologic and immunologic characteristics of NLPHD are preserved in extranodal sites and allow its distinction from classic Hodgkin's disease and other lymphoproliferative malignancies that may occur in extranodal sites.

Adolescent↗
PubMed1995

Malignant lymphomas that mimic benign lymphoid lesions: a review of four lymphomas.

Lymphomas that may be misdiagnosed as benign lymphoid lesions are described and illustrated in this review. Differential diagnoses are considered, and the use of specialized techniques in diagnostic pathology are discussed. The four lymphomas selected for review include follicular lymphoma, mantle cell lymphoma with mantle zone pattern, interfollicular Hodgkin's disease, and nodular lymphocyte predominance Hodgkin's disease.

Diagnosis, Differential↗
PubMed1994

Polymorphic reticulosis: a reappraisal.

We studied 18 patients (15 men and three women) evaluated for a destructive sinonasal lesion that had been diagnosed as "polymorphic reticulosis." The histologic features of each lesion were those of angiocentric immunoproliferative lesions," characterized by atypical lymphoid infiltrates with polymorphous, angiocentric, and necrotic features; 13 were grade 2 and five were grade 3. The neoplastic cells in each patient had a T-cell phenotype. Epstein-Barr virus RNA was detected in the neoplastic cells of 17 of the 18 T-cell lesions. Initial treatment consisted of local radiation therapy in each patient, chemotherapy in two patients, and prednisone in another patient. Two patients were lost to follow-up and the other 16 had a median follow-up of 14 years, 2 months (range, 4 months to 32 years, 5 months). Four patients are alive and disease free, four patients died not of disease or complication of therapy, and eight patients died of disease. The Kaplan-Meier estimate of survival was 63% at 5 years and 50% at 15 years. Histologic progression of angiocentric immunoproliferative lesions from grade 2 to grade 3 was observed in two patients, and a correlation between angiocentric immunoproliferative grade and survival could not be detected. These data suggest that polymorphic reticulosis is an Epstein-Barr virus-related angiocentric T-cell lymphoma.

Adult↗
PubMed1994

Detection of Epstein-Barr viral RNA in sinonasal undifferentiated carcinoma from Western and Asian patients.

Undifferentiated carcinoma of the nasopharynx has a well-known association with Epstein-Barr virus (EBV), but only an inconsistent relationship has been identified in undifferentiated carcinomas occurring at other sites. We investigated 22 formalin-fixed, paraffin-embedded cases of sinonasal undifferentiated carcinomas (SNUCs) occurring in Western and Asian patients. A highly sensitive in situ hybridization method was performed using an antisense oligonucleotide probe to the EBER1 gene of EBV. We identified EBV RNA in seven of 11 SNUCs from Asian patients, but in none of the Western SNUC patients (0/11). The EBER1 signal was present in all or virtually all of the tumor cell nuclei in the seven EBV-RNA-positive Asian SNUCs. The latent membrane protein-1 (LMP1) of EBV was not identified in any of the five positive cases tested. Our results suggest that genetic predisposition or environmental/geographical cofactors play an important role in determining the strength of the association of SNUC with EBV.

Adult↗
PubMed1994

Follicular small lymphocytic lymphoma.

We herein provide evidence for the existence of a distinct morphologic form of small lymphocytic lymphoma (SLL) that we term follicular small lymphocytic lymphoma (FSLL). Nine specimens of FSLL from eight patients were studied. The lymphomas in this study showed a true follicular pattern that was independent of tissue planes; the cytologic composition was identical to that seen in SLL. All six of the specimens (from five patients) for which paraffin tissue was available marked as B cell phenotype and were positive for bcl-2 protein. Polymerase chain reaction studies performed on deparaffinized tissue sections showed bcl-2 major breakpoint region rearrangements in four of five cases for which study tissue was available. Clinical information was available for all eight patients. All patients presented with lymph node disease, and three patients also had extranodal involvement at the time of presentation. Three of the patients had a relapse of disease after 33-95 months, and two of these patients died soon after relapse. Another two of the eight patients never responded to chemotherapy and died of their disease after 2 and 8 months, respectively. Two patients died of causes unrelated to their lymphoma and unrelated to any lymphoma therapy. Only one patient remains disease-free, after 65 months; this patient had a relapse at 44 months. The finding of bcl-2 rearrangements suggests that the pathogenesis of FSLL is more closely related to follicular small cleaved cell lymphoma than to classic SLL.

Aged↗
PubMed1994

Increased production of tumor necrosis factor-alpha and release of soluble CD4 and CD8 molecules, but decreased responsiveness to phytohemagglutinin in patients with nasopharyngeal carcinoma.

Twelve patients with nasopharyngeal carcinoma (NPC) were studied for spontaneous and phytohemagglutin (PHA)-stimulated production of cytokines, soluble markers and [3H] thymidine incorporation by mononuclear cells. The same number of patients with skin cancer and healthy subjects were used as control groups. Our results showed that the NPC group produced much more tumor necrosis factor-alpha (TNF alpha), soluble CD4 (sCD4) and CD8 (sCD8) in PHA-stimulated mononuclear cell supernatants than those in the other two groups. The levels of soluble interleukin-2 receptor (sIL-2R) and gamma-interferon (IFN gamma) in PHA-stimulated supernatants were at the same high level in the NPC and healthy subjects groups while the concentrations were much lower in the skin cancer group. We also noticed that the early stage group in NPC patients had higher levels of interleukin-1 alpha (IL-1 alpha), TNF alpha, IFN gamma and sIL-2R in both spontaneous and PHA-stimulated mononuclear cell supernatants. The stimulation index of PHA-responsiveness was 155, 5.2 and 37, respectively, in the healthy subjects, skin cancer and NPC groups. The PHA-responsiveness was depressed in both the NPC and skin cancer groups. It seems that cancer patients have an impaired T cell mitogenic response after mitogen stimulation. NPC patients had better immune response than skin cancer patients in immune factor release or PHA-responsiveness.

Adolescent↗
PubMed1993

Prognostic significance of immunohistochemical analysis of cathepsin D in low-stage breast cancer.

BACKGROUND: Cathepsin D is an estrogen-regulated lysosomal protease that may be overexpressed in breast cancer. Several studies based on biochemical analysis of tumor cytosol have shown that high levels of cathepsin D are associated with poor outcome in patients with breast cancer. In contrast, a few immunohistochemical studies have shown that cathepsin D positivity in breast cancer cells indicates a favorable prognostic outcome or is of no prognostic significance. METHODS: Because of the current controversy, the authors studied, using immunohistochemistry, the distribution (0 to 3) and intensity (0 to 3) of cathepsin D in Stage I and II infiltrating ductal carcinoma of the breast from 245 patients treated at the City of Hope National Medical Center, Duarte, California, from 1970 to 1986. A commercially available rabbit antiserum to purified human cathepsin D and the standard avidin-biotin complex method were used. Statistical analysis was based on a combined low (0 or 2) or high (3 to 6) score. RESULTS: A high cathepsin D score was associated with Stage II disease (P = 0.007), positive lymph nodes (P = 0.019), high nuclear grade (P = 0.005), and c-erbB-2 oncogene amplification (P = 0.013). Cathepsin D positivity was not an independent prognostic indicator of disease-free survival (DFS) or overall survival (OS). In a subgroup analysis, the presence of cathepsin D had only a modest association with predicting a shorter DFS in patients with negative lymph nodes (P = 0.072) or positive progesterone receptors (PR) (P = 0.086). CONCLUSIONS: Immunohistochemical analysis of cathepsin D, with the antiserum used in this study, is not an independent predictor of outcome in patients with breast cancer because of its strong associations with several well-established prognostic indicators.

Adult↗
PubMed1993

High prevalence of Epstein-Barr virus in the Reed-Sternberg cells of Hodgkin's disease occurring in Peru.

The Epstein-Barr virus (EBV) has been implicated in the pathogenesis of Hodgkin's disease (HD). This study was undertaken to determine whether the association of EBV with HD showed geographical variation, as in Burkitt's lymphoma. We studied 32 formalin-fixed, paraffin-embedded cases of HD occurring in Peru. EBV DNA-RNA in situ hybridization was performed using a 30-base biotinylated antisense oligonucleotide complementary to the EBER1 gene of EBV. EBV immunohistochemistry was also performed, using a monoclonal antibody (MoAb) to the latent membrane protein (LMP1) of EBV. Identification of the precise cellular subset staining with EBV was accomplished via double-labeling with MoAbs directed against Reed-Sternberg cells (LeuM1/CD15) and B cells (L26/CD20). EBV RNA was identified in all or virtually all of the Reed-Sternberg cells and variants in 30 of the 32 (94%) cases of HD by in situ hybridization. LMP1 expression was identified in 83% of the EBER1-positive cases. Double-labeling studies confirmed the localization of EBV RNA to CD15-expressing Hodgkin's cells. This study found an extremely high prevalence of EBV in Peruvian HD, in contrast to the much lower percentage of EBV-associated cases of HD occurring in "Western" patients.

Adolescent↗
PubMed1993

Lack of evidence of Epstein-Barr virus in hairy cell leukemia and monocytoid B-cell lymphoma.

An association between the Epstein-Barr virus (EBV) and hairy cell leukemia (HCL) has been reported. Due to the similarities between HCL and monocytoid B-cell lymphoma (MBCL), an association between EBV and MBCL has been postulated. To address these issues we studied 27 spleens from cases with HCL and 13 tissue specimens from cases with MBCL from various sites for evidence of EBV DNA and RNA by in situ hybridization. Using a genomic EBV internal repeat probe and an oligonucleotide probe directed against the EBER1 gene, we were unable to identify EBV DNA or RNA, respectively, in the tumor cells of any of the cases. The results of our study suggest that EBV may not be strongly linked with either HCL or MBCL.

DNA, Viral↗
PubMed1993

The bone marrow agar section: a morphologic and immunohistochemical evaluation.

A technique for agar embedding of bone marrow aspirate particles is compared with the conventional aspirate smear and bone marrow biopsy by reviewing 503 consecutive bone marrow specimens. Immunohistochemical studies were performed on both agar sections and bone marrow biopsies on 43 paired specimens to compare the results between the two preparations. The results were also compared with traditional clot sections from ten control cases. Of the 382 cases with agar sections, 97.7% contained material in the agar that was diagnostic alone or supportive of the diagnosis made with the biopsy and aspirate smear. In two cases (0.4%), focal involvement by lymphoma was identified on the agar section but not in the biopsy sections or aspirate smears. The immunohistochemical studies showed superior immunoreactivity in agar sections by lymphoproliferative disorders when compared with bone marrow biopsy sections. Similar results between agar and conventional biopsy sections were found in cases of metastatic carcinoma and plasma cell dyscrasias.

Adolescent↗