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Biomedical subjects

Y T Jin

Publications and source records attributed to Y T Jin.

At least 37 records · Page 2Linked to original sources
PubMed1999

Immunolocalization of BRCA1 protein in normal breast tissue and sporadic invasive ductal carcinomas: a correlation with other biological parameters.

AIM: BRCA1, a nuclear phosphoprotein, normally functions as a negative regulator of the cell cycle and may be an active inhibitor of neoplastic progression. Mutation of the BRCA1 gene has been demonstrated in 80% of familial breast cancer. Decreased mRNA levels or aberrant subcellular locations of BRCA1 have been identified in breast cancer lines and in sporadic cases of breast cancer tissues. The expression of BRCA1 in large series of variously differentiated breast carcinomas with correlation with other biological parameters has not been clarified. METHODS AND RESULTS: The BRCA1 expression in normal breast tissue (n = 15) and in sporadic cases of invasive ductal carcinoma (n=108) was determined using immunohistochemistry. BRCA1 expression was correlated with other prognostic parameters including p53, c-erbB-2, bcl-2, oestrogen receptor (ER), histological grade, tumour size, axillary lymph node status and age. BRCA1 was exclusively (100%) localized in the nuclei of normal ductal and lobular epithelia. However, this nuclear expression pattern was variable in breast carcinoma (76.8%). Loss of nuclear BRCA1 expression (22 of 108 cases, 20.4%) correlated well with high histological grade (P<0.025) and bcl-2-negative tumours (P<0.05) and frequently in ER-negative tumours. CONCLUSION: BRCA1 nuclear expression could be considered to represent the normal or physiological phenotype. Complete loss of BRCA1 nuclear expression in breast cancer and its correlation with other poor prognostic markers suggest that BRCA1 expression may play an important role in the pathogenesis and prognosis of sporadic breast carcinoma. Altered BRCA1 phenotype may therefore provide an additional prognostic parameter for breast cancer.

Adult↗
PubMed1999

Disseminated Mycobacterium genavense infection in a patient with acquired immunodeficiency syndrome: first case report in Taiwan.

Mycobacterium genavense is a recently described fastidious mycobacterium identified as a pathogen causing disseminated infection in patients with advanced human immunodeficiency virus (HIV) disease. In this report, we describe the first reported case of disseminated M. genavense infection in a patient with acquired immunodeficiency syndrome (AIDS) in Taiwan. A 22-year-old Chinese man was found to be seropositive for HIV at age 18, in 1993. In 1997, he presented with abdominal pain, weight loss, low CD4 lymphocyte count, hepatomegaly, and generalized lymphadenopathy. Microscopic examination of a biopsy specimen from an inguinal lymph node showed both ill- and well-formed noncaseating granulomas. Numerous acid-fast bacilli were present in the histiocyte cytoplasm. Although the organism did not grow on conventional solid media used in our laboratory, two molecular biology techniques, including polymerase chain reaction (PCR) followed by sequencing of 16S rRNA, and PCR together with restriction enzyme fragment polymorphism analysis, confirmed the M. genavense infection. The patient's abdominal symptoms responded well to a chemotherapy regimen that included ethambutol, ciprofloxacin, and clarithromycin, and he survived more than 6 months after diagnosis. However, the lymphadenopathy was still present at his final follow-up. Our report indicates that disseminated infection with M. genavense should be added to the list of differential diagnoses of secondary infections in advanced AIDS patients in Taiwan.

AIDS-Related Opportunistic Infections↗
PubMed1998

Epstein-Barr virus-associated nonsmall cell lung carcinoma: undifferentiated "lymphoepithelioma-like" carcinoma as a distinct entity with better prognosis.

BACKGROUND: Epstein-Barr virus (EBV) infection in nonsmall cell lung carcinoma (NSCLC) has been demonstrated in some ethnic groups. The pathobiology and the role of EBV and oncoprotein expression in these tumors have not been studied extensively. In this study, the authors investigated EBV-encoded RNA-1 (EBER1) transcripts by in situ hybridization and the expression of latent membrane protein-1 (LMP-1) and bcl-2 protein by immunohistochemistry in NSCLC patients from Taiwan, where nasopharyngeal carcinoma is endemic. METHODS: A total of 127 cases of NSCLC (43 cases of squamous cell carcinoma [SCC], 67 cases of adenocarcinoma [AD], 12 cases of large cell carcinoma [LCC], and 5 cases of lymphoepithelioma-like carcinoma [LE]) were included. A sensitive polymerase chain reaction-derived, digoxigenin-labeled DNA probe for in situ detection of EBER1 transcripts was performed for the detection of EBV. Immunohistochemistry using the avidin-biotin-immunoperoxidase method was also performed to evaluate the expression of bcl-2 and LMP-1. RESULTS: EBER1 was detected in 11 of the 127 NSCLC cases (8.7%; 6 SCC cases and 5 LE cases). All 5 LE cases were EBV-positive, whereas only 6 of the 43 SCC cases (14%), 0 of 67 AD cases, and 12 LCC cases were EBV-positive (P < 0.05). All five LE cases showed diffuse, strong, positive staining of tumor cells; five of the six SCC cases showed diffuse but weak staining. Among the nontumor epithelial cells, there was no EBER1 staining of any of the 11 EBER1-positive cases. The mean age of the LE patients was 10 years younger than that of the patients with other histological types. All 5 LE patients were nonsmokers, whereas 3 of the 6 patients with EBER1-positive SCC (50%) were smokers. EBER1 expression did not correlate with the 2-year survival rate of overall cases, but all 5 LE patients were alive without clinical evidence of disease at last follow-up. Gender, lymph node or distant metastasis, and clinical stage were not found to have any correlation with EBER1 expression (P > 0.05). All LE cases had bcl-2 oncoprotein expression (100%). This frequency was significantly different from other histologic types (P < 0.05). The LMP-1 detection rate was low and demonstrated no correlation with bcl-2 expression. CONCLUSIONS: In this study, the authors found that the primary LE of the lung is associated with young age, a history of not smoking, high bcl-2 immunoreactivity, and better survival rate. These characteristics demonstrate that EBV-associated LE of the lung is a unique entity. The findings of the current study suggest that EBV infection may play a different role in the tumorigenesis of primary LE of the lung than it does in other EBER1-positive NSCLCs.

Adult↗
PubMed1998

The prognostic significance of the biomarkers p21WAF1/CIP1, p53, and bcl-2 in laryngeal squamous cell carcinoma.

BACKGROUND: The clinical course of laryngeal squamous cell carcinoma (LSCC) varies considerably among patients. New biologic markers are needed to facilitate the stratification of individual patients within the conventional clinicopathologic stages of LSCC. METHODS: Eighty-three LSCCs from an equal number of patients who received at least 10 years of follow-up were investigated for p53, p21WAF1/CIP1, and bcl-2 protein expression by immunohistochemical techniques. The results were correlated with various clinicopathologic parameters, DNA content, and patient outcome by univariate and multivariate statistical analyses. RESULTS: Stage IV disease, large tumor size (>3 cm), positive lymph node status, extranodal extension, and p53 overexpression (in > 75% of cells) correlated significantly with prognosis in univariate analysis. There was no correlation between patient outcome and age, gender, race, histologic differentiation, or expression of bcl-2 or p21WAF1/CIP1. In multivariate analysis, lymph node status and p53 overexpression were the only factors significantly associated with survival. CONCLUSIONS: High p53 expression and positive lymph node status were independent predictors of the outcomes of patients with LSCC. These factors may assist in prognostication and better classification of patients for treatment.

Adult↗
PubMed1998

Epstein-Barr virus detection in nasopharyngeal tissues of patients with suspected nasopharyngeal carcinoma.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is strongly associated with Epstein-Barr virus (EBV). Detection of EBV in biopsy specimens may serve as a tumor marker. METHODS: To assess the sensitivity and specificity of the polymerase chain reaction (PCR) and in situ hybridization in the diagnosis of NPC, formalin fixed, paraffin embedded nasopharyngeal biopsies from patients in Taiwan suspected of having NPC were studied. RESULTS: In specimens from 107 patients with NPC, EBV was detected by PCR in 97 cases (90.7%) and by EBER in situ hybridization in 105 cases (98.1%). In specimens from 61 patients without neoplasia, EBV was detected by PCR in 7 cases (11.5%) and by EBER in situ hybridization in 0 cases. CONCLUSIONS: These results suggest that although EBV DNA may occasionally be detected in nonneoplastic nasopharyngeal tissues, cells expressing EBER are not. EBER in situ hybridization may therefore prove to be a useful adjunct in the diagnosis of NPC.

Biopsy↗
PubMed1998

Differentiation of BCG-induced lymphadenitis from tuberculosis in lymph node biopsy specimens by molecular analyses of pncA and oxyR.

Without culture, differentiation of bacille Calmette-Guérin-induced lymphadenitis (BCG-LA) from tuberculosis (TB) is sometimes difficult by histology, but is important because of different treatment schemes. The purpose of this study was to investigate the feasibility of differentiating BCG-LA from TB in lymph nodes (LNs) by molecular analyses of two recently identified genes, pncA and oxyR. In both genes, a single tuberculosis difference exists between Mycobacterium bovis and M. tuberculosis. M tuberculosis complex (MTC) DNA was first detected in nine of ten formalin-fixed, paraffin-embedded LNs from patients aged under 20 years with suspected mycobacterial infections, using polymerase chain reaction (PCR) for IS6110, an insertion sequence specific for MTC species. PCR, together with direct DNA sequencing and PCR-restriction fragment length polymorphism (RFLP) assay, was then performed to identify polymorphic nucleotide in pncA and oxyR, respectively. For comparison, 37 adult cases of tuberculous lymphadenitis were also analysed by PCR-single strand conformation polymorphism (SSCP) assay for pncA and by PCR-RFLP for oxyR. The results revealed that five of the nine IS6110-positive child cases had a G residue at nucleotide 169 in pncA, and also had a three-band pattern after digesting the amplified oxyR segment with AluI, suggesting BCG-LA. The remaining four child cases, as well as all adult cases with detectable IS6110, showed no motility shift in pncA PCR-SSCP and had the same one-band pattern as M. tuberculosis in oxyR PCR-RFLP, suggesting TB lymphadenitis. The data from molecular analyses showed a good correlation with the vaccination history and clinicopathological findings, except for one case. This study indicates that molecular assay of either oxyR or pncA could be a rapid and useful tool to distinguish BCG-LA from TB.

Adolescent↗
PubMed1998

Role of streptococcal pyrogenic exotoxin B in the mouse model of group A streptococcal infection.

Streptococcal pyrogenic exotoxin B (SPE B) is a cysteine protease produced by Streptococcus pyogenes. In this study, the differences in virulence between protease-positive clinical isolates and their protease-negative mutants were examined in a mouse model. Isogenic protease-negative mutants were constructed by homologous recombination, using integrational plasmids to disrupt the speB gene. These mutants caused less mortality and tissue damage than protease-positive strains when inoculated into BALB/c mice via air pouch, suggesting that SPE B cysteine protease plays an important role in the pathogenesis of S. pyogenes infection. Reconstitution of SPE B in the air pouches increased the mortality of mice receiving the speB mutant strain. Infiltrated cell numbers in the exudates from the air pouches of mice infected with SPE B-producing S. pyogenes were higher than those from mice infected with protease-negative mutants at 12 h. However, despite pretreatment with vinblastine to deplete neutrophils, injection of protease-positive bacteria still resulted in severe tissue injury, indicating that neutrophil infiltration may not be the major factor involved in SPE B-enhanced tissue damage. The role of SPE B was further confirmed by demonstrating that SPE B immunization of mice conferred protection from challenge with a lethal dose of protease-positive bacteria.

Animals↗
PubMed1998

Application of endoscopic sinus surgery to primary atrophic rhinitis? A clinical trial.

The aetiology of primary atrophic rhinitis (AR) is still unclear. Based on the sinus infection theories, endoscopic sinus surgery (ESS) was applied to treat AR. ESS was performed on 14 patients following Stammberger's techniques along with middle turbinectomy. Patients were evaluated using clinical symptoms, radiological sinus images, saccharine time tests, bacterial cultures and mucosal ultrastructures, before and 2 years after ESS. Three patients had good recoveries, 6 had partial recoveries and another 5 had persistent disease. Good recovery patients showed clear nasal cavities and mucociliary transport system normalisation. Patients possess in meagre infectious signs or crusting extending to their nasopharynx had poor outcomes. Patients with evidence of obvious infections (cloudy sinus images, mucopus presence in the sinuses and positive culture for Klebsiella ozaenae) had good recoveries following ESS. Candidate selection is critical for the success of ESS treatment in AR. Although further clinical trials are required to prove this strategy.

Adolescent↗
PubMed1997

High prevalence of human papillomavirus types 16 and 18 in middle-ear carcinomas.

Chronic suppurative otitis media, averaging 20 or more years of duration, has been associated with cancer in this region in 40%-80% of cases. Although human papillomaviruses (HPV) have been implicated in many human squamous-cell neoplasms, their role in the pathogenesis of middle-ear malignancies remains unexplored. In this study, we investigated the presence and subtypes of HPV in middle-ear carcinomas. Formalin-fixed and paraffin-embedded tumor tissues were sampled for DNA extraction. PCR was done with consensus primers, capable of detecting HPV 16, 18, 31, 33, 52b and 58. Typing of the products generated by consensus primers was performed with restriction enzyme digestion. It was found that a resulting 89% (8/9) of the middle-ear carcinomas contained HPV DNA. Coexistence of HPV 16 and 18 was detected in 3 squamous-cell carcinomas. HPV 16 was detected in 4 squamous-cell carcinomas and 1 adenocarcinoma. The high prevalence of high-risk-type HPV in carcinomas of the middle ear suggests that viral infection may be an important etiologic component in the carcinogenic process.

Adenocarcinoma↗
PubMed1997

Kaposi's sarcoma-associated herpesvirus-like DNA sequences (KSHV/HHV-8) in oral AIDS-Kaposi's sarcoma: a PCR and clinicopathologic study.

Recently, a new human herpesvirus (KSHV/HHV-8) has been identified in classic, transplant, endemic, and AIDS Kaposi's sarcoma that may be involved in the pathogenesis of Kaposi's sarcoma. The purpose of this study was to evaluate oral AIDS-Kaposi's sarcoma for detection of KSHV/HHV-8 DNA. DNA extracted from 54 oral AIDS-Kaposi's sarcoma lesions (47 initial, 7 postvinblastine treated), 5 non-Kaposi's sarcoma HIV-positive lesions, and 3 non-Kaposi's sarcoma HIV-negative lesions was evaluated by polymerase chain reaction (KS330(233bp)amplicon) for KSHV/HHV-8. The AIDS-Kaposi's sarcoma study population consisted of 52 patients (51:1, men:woman; 92% men having sex with men, 8% heterosexual; mean age, 38 years; mean, CD4 59/mm3) Opportunistic infections occurred in 88% (candidiasis, 65%; Pneumocystis carinii pneumonia, 31%; nonoral Kaposi's sarcoma, 25%; mycobacterium avium-intracellulare (MAI), 16%; cytomegalovirus, 14%; herpes simplex virus, 14%). Sexually transmitted diseases occurred in 73% (gonorrhea, 37%; syphilis, 23%; condyloma, 22%; HSV, 16%). Most frequent lesion sites were palate (74%) and gingiva (17%). Most common lesion types were purple nodular (48%) and macular (42%). Histopathologic subtypes were nodular (71%), plaque (27%), and patch (2%). Polymerase chain reaction analysis detected KSHV/HHV-8 DNA in 53 of 54 AIDS-Kaposi's sarcoma lesions (47 of 47 initial, 6 of 7 postvinblastine treatment). KSHV/HHV-8 DNA was not detected in non-Kaposi's sarcoma lesions in HIV-positive or HIV-negative persons. KSHV/HHV-8 DNA sequence is present in a high proportion of oral AIDS-Kaposi's sarcoma lesions. Whether KSHV/HHV-8 is an etiologic agent or a cofactor in the development of this vascular neoplasm is uncertain and remains to be proven. Polymerase chain reaction analysis for KSHV/HHV-8 DNA sequence detection may be helpful in identifying Kaposi's sarcoma in early vascular proliferations, when the characteristic histopathologic features are not present.

AIDS-Related Opportunistic Infections↗
PubMed1997

Prevalence of human papillomavirus in middle ear carcinoma associated with chronic otitis media.

Squamous cell carcinoma of the middle ear (MESCC) is an uncommon tumor and is associated with a history of long-term chronic otitis media (COM) in most cases. Although the human papillomaviruses (HPVs) have been implicated in many human neoplasms, its role in the pathogenesis of MESCC has not been studied. Polymerase chain reaction (PCR) using consensus primers for the detection of HPV types 6, 11, 16, 18, 31, 33, 52b, and 58 was applied in screening fourteen cases of MESCC from archival material. Further subtyping was performed by restriction enzyme digestion of PCR products and by in situ hybridization method on tissue sections. Of the fourteen cases of MESCC, eleven were found to have HPV DNA. HPV-16 was detected in all positive cases. Five cases revealed both HPV-16 and -18. A history of long-term COM (> 3 years) was found in thirteen of the cases. This is the first report to localize HPV-16/18 in MESCC on both the tissue level and the molecular level. The high prevalence of HPV in COM-associated MESCC therefore provides a good model to explain the pathogenesis of chronic-inflammation-related human malignancies.

Adult↗
PubMed1996

Expression of EBER1 in primary and metastatic nasopharyngeal carcinoma tissues using in situ hybridization. A correlation with WHO histologic subtypes.

BACKGROUND: The association of Epstein-Barr virus (EBV) with nasopharyngeal carcinoma (NPC) is well documented. Previous studies reported abundant expression of EBER1 in primary NPC and tumors metastatic to lymph nodes. However, a large series of case studies correlating World Health Organization (WHO) histologic subtypes with EBER1 is needed. METHODS: The authors applied the EBER1 in situ hybridization to investigate the expression of EBER1 in 140 primary NPCs, 11 metastatic tumors to lymph nodes, 6 metastatic tumors to bone marrow, and 2 metastatic tumors to the liver. All 19 metastatic tumors had paired specimens from their primary NPCs for comparison. The in situ hybridization method was performed on paraffin embedded tissues by using polymerase chain reaction-derived, digoxigenin-labelled EBER1 DNA probes. RESULTS: The EBER1 signal was identified in nuclei of malignant epithelial cells in 135 of 140 (96.4%) primary NPCs, including 4 of 5 (80%) WHO-I histologic subtypes, 71 of 73 (97.3%) WHO-II histologic subtypes, and 60 of 62 (96.8%) WHO-III histologic subtypes (P > 0.05). However, the positive hybridization signal in WHO-I NPC was less in proportion to malignant cells, usually limited to basal cells, than in other histologic types of NPC. In 10 of 11 specimens with metastases to the lymph nodes, hybridization was always limited to the malignant cells and not associated with lymphocytes. All 10 paired primary NPCs also demonstrated positive EBER1 hybridization. Only one paired specimen showed negative EBER1 in primary NPC and a metastases to a lymph node. Eight distant metastases, all EBER1-positive in their primary NPC, also demonstrated positive EBER1 hybridization signals in the malignant cells. The proportion of EBER1 positivity in metastatic NPC is higher than that in primary lesions as observed in paired specimens from the same patient. CONCLUSIONS: Because of abundant expression of EBER1 in primary NPC as well as in metastatic malignant cells, it is recommended that EBER1 in situ hybridization be performed on routinely processed specimens whenever NPC is suspected.

Base Sequence↗
PubMed1996

Studies on promoting activity of Taiwan betel quid ingredients in hamster buccal pouch carcinogenesis.

Previous studies indicated that Taiwan betel quid is a promoter rather than an initiator during the carcinogenesis of hamster buccal pouch carcinoma. The maximum promoting activity can be demonstrated 24 weeks after betel quid implantation, following an initial application of 0.5% DMBA (7,12-dimethyl benzanthracene) three times per week for 4 weeks. In the present study, components of Taiwan betel quid and its additives (dry betel nut fibre, piper betel, slaked lime, cold aqueous extract, and hot aqueous extract) were applied respectively or in various combinations to investigate their promoting activity. One hundred and thirty Syrian hamsters were divided into 13 groups based on different combinations of the betel quid ingredients applied. The incidence of tumours in the hamster buccal pouch was significantly higher in groups exposed to dry betel nut fibre (P < 0.01) and cold aqueous extract (P < 0.05). The results indicate that betel nut fibre and cold aqueous extract are the major components of betel quid that may promote carcinogenesis in the hamster buccal pouch.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed1996

Detection of bcl-2 and p53 in thymoma: expression of bcl-2 as a reliable marker of tumor aggressiveness.

The distinction between noninvasive and invasive or malignant thymoma has been severely compromised by a lack of objective morphological criteria. A reliable marker of tumor aggressiveness is, therefore, mandatory for predicting the tumor behavior. Forty thymic epithelial tumors, including 5 noninvasive thymomas, 18 invasive thymomas, and 17 thymic carcinomas (Rosai's classification) were investigated for expression of bcl-2 and p53 proteins by immunohistochemistry. The thymic epithelial cells showed positive immunostain for bcl-2 in 0, 7, and 16 of these categories, respectively. Thymic carcinomas had a significantly higher proportion of bcl-2 expression than thymomas (P < .0001). A significantly higher expression of bcl-2 protein was also shown in thymoma-associated myasthenia gravis (P < .05). However, p53 showed no correlation with the histological subtypes nor clinical aggressiveness. Bcl-2 expression appeared to be positively correlated with p53 immunoreactivity, but this result was not statistically significant (P = .07). In conclusion, these data indicate that bcl-2 expression correlates with aggressiveness in thymic epithelial neoplasms.

Biomarkers, Tumor↗
PubMed1996

Autologous pericranial graft resurfacing after high condylectomy and discectomy of the temporomandibular joint in rabbits.

PURPOSE: This study tested the effects of an autologous pericranial graft placed over the condyle on healing after high condylectomy and discectomy. MATERIALS AND METHODS: Sixteen young adult New Zealand white rabbits were divided into four test groups and a control group. Three animals from the test group and one control animal were killed at 2, 4, 8, and 12 weeks postoperatively. Each experimental animal received a high condylotomy and discectomy bilaterally. In addition, on one side a pericranial graft was placed on the shaved bone and immobilized with a tissue adhesive. RESULTS: The results showed better healing of the articular defects in the joints where grafts had been placed, including earlier and more complete soft tissue covering, more substantial neochondrogenesis, and better organization of the regenerated articular cartilage. CONCLUSION: Pericranial grafts may be helpful in facilitating healing after high condylectomy. However, technical improvements in the method of tissue fixation may be necessary.

Animals↗
PubMed1996

Presence of human herpesvirus-like DNA sequence in oral Kaposi's sarcoma. A preliminary PCR study.

DNA sequences closely related to herpesvirus-like sequences have been found in AIDS-associated Kaposi's sarcoma. Subsequent studies indicate that these DNA sequences may be consistently found in AIDS Kaposi's sarcoma and non-AIDS Kaposi's sarcoma from different geographic regions. Oral Kaposi's sarcoma is rare and the specificity of this viral DNA in oral Kaposi's sarcoma and in other oral neoplasms has not been examined. A total of 77 oral neoplasms, including 3 Kaposi's sarcoma specimens from 2 patients with AIDS, were analyzed by polymerase chain reaction for the presence of this herpesvirus-like DNA sequence with the 330-233 primers. All three specimens of oral AIDS-Kaposi's sarcoma from two patients were positive for this DNA sequence. All of the other intraoral lesions including hemangioma, pyogenic granuloma, and various types of epithelial neoplasms, however, had negative reactions. Our results further confirm that oral Kaposi's sarcoma appears to be associated with this herpesvirus-like DNA sequence.

AIDS-Related Opportunistic Infections↗
PubMed1996

Immunohistochemical localization of Mcl-1 and bcl-2 proteins in thymic epithelial tumours.

Mcl-1 protein is a new member of the bcl-2 protein family. It is believed to be a blocker of apoptosis but might be different from bcl-2 in the control of apoptosis. Using immunostaining of formalin-fixed, paraffin-embedded sections, we investigated the expression of Mcl-1 in 42 thymic epithelial tumours: three medullary thymomas, five mixed thymomas, seven cortical thymomas, eight well-differentiated thymic carcinomas, 14 squamous cell carcinomas, four lymphoepithelioma-like carcinomas and one undifferentiated carcinoma, bcl-2 immunocytochemical localization was also performed for comparison. High-grade thymic carcinomas, especially squamous cell carcinomas, revealed more intense Mcl-1 immunoreactivity as compared to other subtypes (P < 0.001). In cases that co-expressed Mcl-1 and bcl-2, the less differentiated cells had more intense expression of bcl-2, while the more differentiated cells displayed stronger Mcl-1 immunoreactivity. The differential expression of Mcl-1 and bcl-2 in neoplastic cells provides evidence that these proteins may play different roles in the processes of programmed cell death in thymic neoplasms. The finding that thymic carcinomas have stronger immunoreactivity for Mcl-1 indicates that this protein could be a useful marker to differentiate aggressive thymic epithelial tumours from indolent ones.

Carcinoma↗