Non-recurrent Ones Research Articles

Clinical, Imaging, and Pathological-Molecular Characteristics Associated with Stage IA Invasive Lung Adenocarcinoma Recurrence After Sub-lobar Resection

Rationale and ObjectivesThis study aimed to investigate the association of clinical, imaging, and pathological-molecular characteristics with the prediction of patient prognosis with stage IA invasive lung adenocarcinoma (ILADC) after sub-lobar resection. Materials and MethodsThis study assessed 360 patients, including 91 and 269 with and without recurrence 3 years postoperativel, respectively, with stage IA ILADC undergoing preoperative chest computed tomography (CT) scans and subsequent sub-lobar resection at our institution. Their clinical and CT features and histological subtypes and gene mutation status were compared. Binary logistic regression analysis was conducted to identify the independent risk factors for recurrence. An external validation cohort included 113 patients, used to test the model’s efficiency. ResultsFor clinical features, old age, male gender, smokers, and high age-adjusted Charlson comorbidity index (ACCI) were frequently observed in patients with recurrence than those without (all p < 0.05). For CT features, large tumor size, solid-predominant density, spiculation, peripheral fibrosis, type II pleural tag, and pleural adhesion were more common in recurrent patients than non-recurrent ones (all p < 0.05). The regression model revealed old age, large tumor size, solid-predominant density, spiculation, type II pleural tag, and pleural adhesion as independent risk factors for recurrence, with an area under the curve (AUC) of 0.942. The external validation cohort obtained an AUC of 0.958. For phological-molecular features, miropapillary/solid-predominant growth pattern, KRAS, ALK, and NRAS mutation or fusion were more ccommon in the recurrent group, whereas EGFR mutation was more frequent in the non-recurrent group (all p < 0.05). ConclusionClinical and CT features help predict the prognosis of patients with stage IA ILADC after sub-lobar resection and decide for individualized treatment. Moreover, patients with different prognosis demonstrated different pathological-molecular features.

Assessment of vitamin D deficiency in recurrent BPPV patients: A cross-sectional study

PurposeThis study aimed to investigate the vitamin D deficiency of patients with BPPV recurrence and to evaluate the differences of 25-hydroxy vitamin D (25(OH)D) and serum calcium levels among gender and age categories. MethodsThis cross-sectional study enrolled patients with BPPV. The diagnosis of BPPV was based on positional nystagmus and vertigo induced by certain head positions (The Dix-Hallpike maneuver and head roll tests). All patients' age, serum 25(OH)D, calcium measurements and recurrence data were collected and analyzed. ResultsThe median of 25(OH)D was 15.32 (IQR 10.61, 20.90) ng/ml. The recurrent group showed lower 25(OH)D levels than that of non-recurrent group [13.28 (IQR 9.47, 17.57) ng/ml vs 16.21 (IQR 11.49, 21.13) ng/ml]. There were significant differences of 25(OH)D levels among age categories. The proportion of vitamin D deficiency in patients ≥60 years old was lower than that in the other two groups. ConclusionOur study suggested that BPPV patients had a decreased 25(OH)D level and a high incidence of vitamin D deficiency. The 25(OH)D level of recurrent BPPV patients was lower than that in non-recurrent ones. Among them, the elderly group (≥60 years) took the preponderance, which had the lowest incidence of vitamin D deficiency and the highest incidence of vitamin D sufficiency.

Estimation and early prediction of grip force based on sEMG signals and deep recurrent neural networks

Hands are used for communicating with the surrounding environment and have a complex structure that enables them to perform various tasks with their multiple degrees of freedom. Hand amputation can prevent a person from performing their daily activities. In that event, finding a suitable, fast, and reliable alternative for the missing limb can affect the lives of people who suffer from such conditions. As the most important use of the hands is to grasp objects, the purpose of this study is to accurately predict gripping force from surface electromyography (sEMG) signals during a pinch-type grip. In that regard, gripping force and sEMG signals are derived from 10 healthy subjects. Results show that for this task, recurrent networks outperform nonrecurrent ones, such as a fully connected multilayer perceptron (MLP) network. Gated recurrent unit (GRU) and long short-term memory (LSTM) networks can predict the gripping force with R-squared values of 0.994 and 0.992, respectively, and a prediction rate of over 1300 predictions per second. The predominant advantage of using such frameworks is that the gripping force can be predicted straight from preprocessed sEMG signals without any form of feature extraction, not to mention the ability to predict future force values using larger prediction horizons adequately. The methods presented in this study can be used in the myoelectric control of prosthetic hands or robotic grippers.

Exome sequencing as first-tier test for fetuses with severe central nervous system structural anomalies.

ABSTRACTObjectivePrenatally detected central nervous system (CNS) anomalies present a diagnostic challenge. In this study, we compared the diagnostic yield of exome sequencing (ES) and chromosomal microarray analysis (CMA) in fetuses with a major CNS anomaly.MethodsThis was a retrospective study of 114 cases referred for genetic evaluation following termination of pregnancy (TOP) due to a major CNS anomaly detected on prenatal ultrasound. All fetuses were first analyzed by CMA. All CMA‐negative cases were offered ES. CMA‐positive cases were reanalyzed using ES to assess its ability to detect copy‐number variants (CNVs).ResultsCMA identified a pathogenic or likely pathogenic (P/LP) CNV in 11/114 (10%) cases. Eighty‐six CMA‐negative cases were analyzed using ES, which detected P/LP sequence variants in 38/86 (44%). Among recurrent cases (i.e. cases with a previously affected pregnancy), the incidence of P/LP sequence variants was non‐significantly higher compared with non‐recurrent ones (12/19 (63%) vs 26/67 (39%); P = 0.06). Among the 38 cases with an ES diagnosis, 20 (53%) were inherited and carried a significant risk of recurrence. Reanalysis of 10 CMA‐positive cases by ES demonstrated that the bioinformatics pipeline used for sequence variant analysis also detected all P/LP CNVs, as well as three previously known non‐causative CNVs.ConclusionsIn our study, ES provided a high diagnostic yield (> 50%) in fetuses with severe CNS structural anomalies, which may have been partly due to the highly selected case series that included post‐TOP cases from a specialist referral center. These data suggest that ES may be considered as a first‐tier test for the prenatal diagnosis of major fetal CNS anomalies, detecting both P/LP sequence variants and CNVs. This is of particular importance given the time constraints of an ongoing pregnancy and the risk of recurrence in future pregnancies. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Progesterone Receptor Expression in Meningiomas: Pathological and Prognostic Implications.

BackgroundThe progesterone receptor (PR) is variably expressed in most meningiomas and was found to have prognostic significance. However, the correlation with patient age, tumor location, time to recurrence, and pattern of regrowth has scarcely been discussed.MethodsA surgical series of 300 patients with meningiomas is reviewed. The PR expression was classified as: 0. absent; 1. low (<15%); 2. moderately low (16–50%); 3. moderately high (51–79%); 4. high (≥80%). The PR values were correlated with the patient age and sex, meningioma location, WHO grade, Ki-67 MIB1, recurrence rate, pattern of recurrence (local-peripheral versus multicentric diffuse), and time to recurrence.ResultsThe PR expression has shown lower rate of high expression in the elderly group (p = 0.032) and no sex difference (including premenopausal versus postmenopausal women), higher expression in medial skull base and spinal versus other locations (p = 0.0036), inverse correlation with WHO grade and Ki67-MIB1 (p < 0.0001). Meningiomas which recurred showed at initial surgery higher rates of low or moderately low PR expression than the non-recurrent ones (p = 0.0004), whereas the pattern of regrowth was not significant. Higher rates of PR values ≥80% were found in cases with time to recurrence >5 years (p = 0.036).ConclusionThe higher PR expression in medial skull base meningiomas, the significant correlation with the time to recurrence, the lack of difference of PR expression between premenopausal and postmenopausal women and between local-peripheral versus multicentric-diffuse recurrences are the most relevant unreported findings of this study. The rate of PR expression must be included in the routine pathological diagnosis of meningiomas because of its prognostic significance.

Expression of cartilage oligomeric matrix protein in the synovial chondromatosis of the temporomandibular joint

OBJECTIVE To detect the expression of cartilage oligomeric matrix protein (COMP) in the synovial chondromatosis of the temporomandibular joint (TMJSC), and to discuss the possible interactions between COMP, transforming growth factor (TGF)-β3, TGF-β1 and bone morphogenetic protein-2 (BMP-2) in the development of this neoplastic disease. METHODS Patients in Peking University School and Hospital of Stomatology from January 2011 to February 2020 were selected, who had complete medical records, TMJSC was verified histologically after operation. The expressions of COMP, TGF-β3, TGF-β1 and BMP-2 in the TMJSC of the temporomandibular joint were detected by immunohistochemistry and quantitative real-time PCR (RT-PCR) at the protein level and mRNA level respectively, compared with the normal synovial tissue of temporomandibular joint. The histological morphology, protein expression and distribution of TMJSC tissues were observed microscopically, and the positive staining proteins were counted and scored. SPSS 22.0 statistical software was used to analyze the expression differences between the related proteins in TMJSC tissue and the normal synovial tissue of temporomandibular joint and to compare their differences. P < 0.05 indicated that the difference was statistically significant. RESULTS Immunohistochemical results showed that the positive expression of COMP in TMJSC tissues was mostly found in synovial tissues and chondrocytes adjacent to synovial tissues, and the difference was statistically significant, compared with the normal temporomandibular joint synovial tissues. The positive expression of COMP was significantly different between recurrent TMJSC and non-recurrent ones. The positive expressions of TGF-β3, TGF-β1 and BMP-2 were higher than the normal synovial tissue, and were also mostly found in the synovial cells and adjacent chondrocytes, which was further confirmed by Western blot. According to the RT-PCR results, the expressions of COMP, TGF-β3, TGF-β1 and BMP-2 in TMJSC were higher than those in the normal synovial tissue. CONCLUSION The expression of COMP in TMJSC of temporomandibular joint increased significantly, compared with the normal synovial tissue. There may be interactions between COMP and cytokines related to the proliferation and differentiation, like TGF-β3, TGF-β1 and BMP-2, which may play a potential role in the pathogenesis of TMJSC.

Prognostic outcome prediction by semi-supervised least squares classification

Although great progress has been made in prognostic outcome prediction, small sample size remains a challenge in obtaining accurate and robust classifiers. We proposed the Rescaled linear square Regression based Least Squares Learning (RRLSL), a jointly developed semi-supervised feature selection and classifier, for predicting prognostic outcome of cancer patients. RRLSL used the least square regression to identify the scale factors and then rank the features in available multiple types of molecular data. We applied the unlabeled multiple molecular data in conjunction with the labeled data to develop a similarity graph. RRLSL produced the constraint with kernel functions to bridge the gap between label information and geometry information from messenger RNA and microRNA expression profiling. Importantly, this semi-supervised model proposed the least squares learning with L2 regularization to develop a semi-supervised classifier. RRLSL suggested the performance improvement in the prognostic outcome prediction and successfully discriminated between the recurrent patients and non-recurrent ones. We also demonstrated that RRLSL improved the accuracy and Area Under the Precision Recall Curve (AUPRC) as compared to the baseline semi-supervised methods. RRLSL is available for a stand-alone software package (https://github.com/ShiMGLab/RRLSL). A short abstract We proposed the Rescaled linear square Regression based Least Squares Learning (RRLSL), a jointly developed semi-supervised feature selection and classifier, for predicting prognostic outcome of cancer patients. RRLSL used the least square regression to identify the scale factors to rank the features in available multiple types of molecular data. RRLSL produced the constraint with kernel functions to bridge the gap between label information and geometry information from messenger RNA and microRNA expression profiling. Importantly, this semi-supervised model proposed the least squares learning with L2 regularization to develop the semi-supervised classifier. RRLSL suggested the performance improvement in the prognostic outcome prediction and successfully discriminated between the recurrent patients and non-recurrent ones.

Clinical and immunohistochemical analysis of diffuse tenosynovial giant cell tumour of the temporomandibular joint

The objective of this study was to summarize diagnostic points and treatment strategies for diffuse tenosynovial giant cell tumours (D-TSGCTs) of the temporomandibular joint (TMJ), and to evaluate the expression of proteins related to bone destruction and recurrence. The clinical and histopathological characteristics of 24 cases were analysed retrospectively. TRAP staining and immunohistochemical staining for MMP-9, MMP-13, and Ki-67 were performed. The median age of the patients was 45.5 years; the female to male ratio was 1.7:1. In 11 cases (45.8%), skull base destruction seen on computed tomography was confirmed by surgery. Computer-assisted navigation was performed in six cases. Four patients received adjuvant radiotherapy after first surgery. Five patients had recurrent lesions. Multinucleated giant cells were positive for TRAP, MMP-9, and MMP-13. The average Ki-67 index of the recurrent cases was significantly higher than that of the non-recurrent ones (P<0.05). This study demonstrates the aggressive and recurrent nature of D-TSGCT occurring in the TMJ. Computer-assisted navigation is helpful to protect vital structures and determine margins. Adjuvant postoperative radiotherapy is recommended for local control of residual or recurrent tumour. In conclusion, MMP-9 and MMP-13 may play a role in bone destruction of D-TSGCT, and the Ki-67 index has predictive significance for recurrence.

Comprehensive analysis of 204 sporadic hydatidiform moles: revisiting risk factors and their correlations with the molar genotypes.

Hydatidiform mole (HM) is an aberrant human pregnancy characterized by excessive trophoblastic proliferation and abnormal embryonic development. HM has two morphological types, complete (CHM) and partial (PHM), and non-recurrent ones have three genotypic types, androgenetic monospermic, androgenetic dispermic, and triploid dispermic. Most available studies on risk factors predisposing to different types of HM and their malignant transformation mainly suffer from the lack of comprehensive genotypic analysis of large cohorts of molar tissues combined with accurate postmolar hCG follow-up. Moreover, 10-20% of patients with one HM have at least one non-molar miscarriage, which is higher than the frequency of two pregnancy losses in the general population (2-5%), suggesting a common genetic susceptibility to HM and miscarriages. However, the underlying causes of the miscarriages in these patients are unknown. Here, we comprehensively analyzed 204 HM, mostly from patients referred to the Quebec Registry of Trophoblastic Diseases and for which postmolar hCG monitoring is available, and 30 of their non-molar miscarriages. We revisited the risk of maternal age and neoplastic transformation across the different HM genotypic categories and investigated the presence of chromosomal abnormalities in their non-molar miscarriages. We confirm that androgenetic CHM is more prone to gestational trophoblastic neoplasia (GTN) than triploid dispermic PHM, and androgenetic dispermic CHM is more prone to high-risk GTN and choriocarcinoma (CC) than androgenetic monospermic CHM. We also confirm the association between increased maternal age and androgenetic CHM and their malignancies. Most importantly, we demonstrate for the first time that patients with an HM and miscarriages are at higher risk for aneuploid miscarriages [83.3%, 95% confidence interval (CI): 0.653-0.944] than women with sporadic (51.5%, 95% CI: 50.3-52.7%, p value = 0.0003828) or recurrent miscarriages (43.8%, 95% CI: 40.7-47.0%, p value = 0.00002). Our data suggest common genetic female germline defects predisposing to HM and aneuploid non-molar miscarriages in some patients.

Verrucous Carcinoma of Oral Cavity: Experience of North Indian Tertiary Care Institution

Oral verrucous carcinoma is a rare and special form of well-differentiated squamous cell carcinoma with specific clinical and histological features. This tumor grows slowly and locally and is invasive in nature and unlikely to metastasize. It appears as a painless, thick white plaque resembling a cauliflower. The most common sites of oral mucosal involvement include the buccal mucosa, followed by the mandibular alveolar crest, gingiva, and tongue. Surgery has been the first choice of treatment for these lesions, and radiotherapy is controversial; however, surgery combined with radiotherapy is the next most preferable treatment and may have benefits, particularly in cases of extensive lesions. Recurrence rate is high in cases in which either irradiation or surgery alone is performed. The aim of this study is to retrospectively review the cases of oral verrucous carcinoma treated in the last 4 years at a tertiary medical facility of northern India about the demographics, treatment offered, outcome and re-reviewing the pathological findings in recurrent lesions as compared to nonrecurrent ones.

MicroRNAs as prognostic markers in prostate cancer

Prostate cancer (PCa) is the most commonly diagnosed malignancy in men who are especially over the age of 50 years in the western countries. Currently used therapeutic modalities mostly fail to give positive clinical outcomes and nearly 30% of the PCa patients eventually develop clinical recurrence. Therefore, understanding the underlying mechanisms of PCa progression is of paramount importance to help determining the course of disease. In this study, we aimed at profiling the differentially expressed microRNAs in recurrent PCa samples. We profiled the microRNA expression of 20 recurrent and 20 non-recurrent PCa patients with microRNA microarray, and validated the differential expression of significantly deregulated microRNAs in 40 recurrent and 39 non-recurrent PCa specimens using quantitative reverse-transcription PCR (qRT-PCR). Data were statistically analyzed using two-sided Student's t-test, Pearson Correlation test, Receiver operating characteristic (ROC) analysis. Our results demonstrated that a total of 682 probes were significantly deregulated in recurrent versus non-recurrent PCa specimen comparison. Among those, we confirmed the significant downregulation of miR-424 and upregulation of miR-572 with further qRT-PCR analysis in a larger sample set. Further ROC analysis showed that these microRNAs have enough power to distinguish recurrent specimens from non-recurrent ones on their own. Here, we report that differential expression of miR-424 and miR-572 in recurrent PCa specimens can serve as novel biomarkers for prediction of PCa progression.

Role of CDKN2A/p16 expression in the prognostication of oral squamous cell carcinoma

ObjectiveCDKN2A/p16 is a known tumor suppressor gene with a homologous deletion in Oral Squamous cell carcinoma. CDKN2A/p16 is found to be inactivated in a broad spectrum of solid tumors and in more than 80% of OSCC. Molecular alteration of CDKN2A/p16 in progression of OSCC can pose an important tool for the prognosis of squamous cell carcinoma. Material and methodSystematic network analysis was carried out to obtain involvement of CDKN2A/p16 in oral cancer by polysearch and FunDO. In the present study we have screened 104 OSCC patients from eastern region of India for CDKN2A/p16 expression in recurrent and non-recurrent OSCC. The observation was validated by Comparative Genomic Hybridisation and Next generation sequencing in recurrent cases. ResultSystematic analysis revealed direct involvement of CDKN2A/p16 in oral cancer. There was a consistent downregulated expression of CDKN2A/p16 in the recurrent cases. The gene expression study confirmed a >5-fold downregulation of CDKN2A/p16 in recurrent tumors as compared to non-recurrent ones. Array CGH analysis revealed a copy number deletion in the recurrent case. Furthermore, next generation sequencing validated deletion of CDKN2A/p16 and reported it asa common variant with a nonsense mutation having stop /loss of function of the gene in recurrent cases. Recurrent cases with deleted CDKN2A/p16 expression had poor prognosis and low survival rate. ConclusionCDKN2A/p16 frequently alters in oral cancer progression with a deletion/loss of function in the recurrent cases displaying its role in aiding several molecular events for the malignant transformations occurring throughout disease progression.

Recurrent chimeric fusion RNAs in non-cancer tissues and cells.

Gene fusions and their products (RNA and protein) were once thought to be unique features to cancer. However, chimeric RNAs can also be found in normal cells. Here, we performed, curated and analyzed nearly 300 RNA-Seq libraries covering 30 different non-neoplastic human tissues and cells as well as 15 mouse tissues. A large number of fusion transcripts were found. Most fusions were detected only once, while 291 were seen in more than one sample. We focused on the recurrent fusions and performed RNA and protein level validations on a subset. We characterized these fusions based on various features of the fusions, and their parental genes. They tend to be expressed at higher levels relative to their parental genes than the non-recurrent ones. Over half of the recurrent fusions involve neighboring genes transcribing in the same direction. A few sequence motifs were found enriched close to the fusion junction sites. We performed functional analyses on a few widely expressed fusions, and found that silencing them resulted in dramatic reduction in normal cell growth and/or motility. Most chimeras use canonical splicing sites, thus are likely products of ‘intergenic splicing’. We also explored the implications of these non-pathological fusions in cancer and in evolution.

MiR-1 and miR-133b are differentially expressed in patients with recurrent prostate cancer.

Prostate cancer (PCa) is currently the most frequently diagnosed malignancy in the western countries. It is more prevalent in older men with 75% of the incident cases above 65 years old. After radical prostatectomy, approximately 30% of men develop clinical recurrence with elevated serum prostate-specific antigen levels. Therefore, it is important to unravel the molecular mechanisms underlying PCa progression to develop novel diagnostic/therapeutic approaches. In this study, it is aimed to compare the microRNA (miRNA) profile of recurrent and non-recurrent prostate tumor tissues to explore the possible involvement of miRNAs in PCa progression. Total RNA from 41 recurrent and 41 non-recurrent PCa tissue samples were used to investigate the miRNA signature in PCa specimens. First of all, 20 recurrent and 20 non-recurrent PCa samples were profiled using miRNA microarray chips. Of the differentially expressed miRNAs, miR-1, miR-133b and miR-145* were selected for further validation with qRT-PCR in a different set of 21 recurrent and 21 non-recurrent PCa samples. Data were statistically analyzed using two-sided Student's t-test, Pearson Correlation test, Receiver operating characteristic analysis. Our results demonstrated that miR-1 and mir-133b have been significantly downregulated in recurrent PCa specimens in comparison to non-recurrent PCa samples and have sufficient power to distinguish recurrent specimens from non-recurrent ones on their own. Here, we report that the relative expression of miR-1 and mir-133b have been significantly reduced in recurrent PCa specimens in comparison to non-recurrent PCa samples, which can serve as novel biomarkers for prediction of PCa progression.

EMPTY INTERIOR RECURRENCE FOR CONTINUOUS FLOWS ON SURFACES

In this paper we characterize topologically the empty interior subsets of a compact surface S which can be ω-limit sets of recurrent orbits (but not of nonrecurrent ones) of continuous flows on S. This culminates the classification of ω-limit sets for surface flows initiated in [Jiménez &amp; Soler, 2001; Soler, 2003; Jiménez &amp; Soler, 2004a, 2004b]. We also show that this type of ω-limit sets can always be realized (up to topological equivalence) by smooth flows but cannot be realized by analytic flows.

Deceleration of the rotational velocities of sunspot groups during their evolution

Using the Greenwich Photoheliographic Results for the years 1874–1976 the daily rotational velocities for 955 recurrent and 13169 non-recurrent sunspot groups from the first day of their appearance and during their evolution have been determined. The rotational velocities were divided in six latitude strips with a width of five degrees and grouped according to the age of the groups. It was established that the rotational velocities of recurrent and non-recurrent sunspot groups decrease with time in all studied latitude strips. At their birth the recurrent spot groups rotate faster by about 0.15° day−1 than the non-recurrent ones and settle, within the errors of measurements, to an about 0.5° day−1 slower velocity value during the second disc passage. A comparison of our results with helioseismology measurements indicates that in the frame of the anchoring hypothesis, the recurrent sunspot groups at their birth could be coupled to the fast rotating layer at about r=0.93 R⊙.

Prognostic value of Ki-67, CD31 and epidermal growth factor receptor expression in basal cell carcinoma.

Recurrence of basal cell carcinoma following treatment is common, and the majority of recurrences appear in the first 3 years. We examined the original tumors of 26 basal cell carcinoma cases, 14 of whom had a recurrence after an average of 3.7 years, and 12 of whom had no recurrence during an average of 4.4 years follow-up. Using immunohistochemistry, we tested for Ki-67, CD31 and epidermal growth factor receptor expressions in the tumor tissue. The percentages of expression for Ki-67, CD31 and epidermal growth factor receptor were significantly higher in the recurrent tumors than in the non-recurrent ones. Expression of Ki-67 and CD31 was 271.57 +/- 17.91 and 58.1 +/- 9.37 for the recurrent group and 187.08 +/- 21.48 and 23.9 +/- 5.45 for non-recurrent group respectively (p<0.0001; p<0.0001). Expression of epidermal growth factor receptor was positive in all basal cell carcinoma cells. The staining intensity was strong in 57% of recurrent and 8.3% of non-recurrent tumors (p=0.014). These results show that Ki-67, CD31 and epidermal growth factor receptor expression differ between basal cell carcinomas which later recur and those that do not recur.

Allelic imbalance on the long arm of chromosome 21 in human oral squamous cell carcinoma: relationship between allelic imbalances (LOH and MSI) and clinicopathologic features.

Frequent allelic imbalances, including loss of heterozygosity (LOH) and microsatellite instability (MSI), have been found on the long arm of chromosome 21 (21q) in several types of human cancer. This study was designed to identify the tumor suppressor locus (or loci) associated with oral squamous cell carcinoma (SCC) on 21q. In order to understand the details of genetic alterations on chromosome 21, we performed polymerase chain reaction analysis of microsatellite polymorphisms corresponding to ten loci on this chromosome. We examined forty primary tumor tissues, forty corresponding normal tissues, and seven lymph node metastatic tissues. We identified novel tumor suppressor loci in this region in primary oral SCCs. To further determine the role of 21q deletions in oral cavity carcinogenesis, forty oral SCCs were examined for allelic imbalances (LOH or MSI) at 21q using ten microsatellite markers. Among these forty patients, twenty-six (65%) showed LOH at one or more loci. Deletion mapping of these tumors revealed four discrete, commonly deleted regions on the chromosome arm. Furthermore, we detected MSI in seventeen of those tested cases (42.5%). We compared our results with the clinicopathologic features. A number of sites displaying LOH at 21q could be detected in early stage lesions, and the frequencies of LOH tended to be higher in later clinical stages, but no statistical correlation was observed. Our results strongly suggest that allelic imbalances on 21q are involved in the development of oral SCC and that at least four different putative tumor suppressor genes contributing to the pathogenesis of this disease are present on 21q. Furthermore, allelic loss on 21q appears to be a useful indicator for evaluating the malignancy and prognosis of oral SCC, because the LOH of recurrent cases was more frequent than that of non-recurrent ones.

Determination of the levels of expression of sarcolectin and calcyclin and of the percentages of apoptotic but not proliferating cells to enable distinction between recurrent and nonrecurrent cholesteatomas.

To investigate in a series of cholesteatomas 1. whether subgroups of cholesteatomas with specific proliferative/apoptotic features exhibit distinct differentiation markers and 2. whether these different subgroups identified at the biological level relate to specific groups of clinically identified cholesteatomas. Analysis of 55 cholesteatomas resected by the same surgeon, by means of canal wall up and canal wall down surgical procedures. Two differentiation markers were used: biotinylated sarcolectin (to identify sarcolectin-binding sites) and a monoclonal antibody directed against calcyclin (which is the S100A6 protein). The growth pattern in cholesteatomas was characterized at three distinct levels: 1. the cell proliferation level determined by means of the MIB-1 antibody, which enables the Ki-67 cell-cycle-related antigen to be identified on archival material; 2. the apoptosis level determined by means of the in situ labeling of nuclear DNA fragmentation (TUNEL staining); and 3. the p53 tumor suppressor gene-related product determined by means of p53 immunohistochemistry. The cholesteatomas that exhibited the highest proportion of apoptotic cells were those which exhibited the highest level of sarcolectin-binding sites (i.e., sialic acids). In contrast, the cholesteatomas exhibiting the lowest level of both proliferation and apoptosis showed the highest level of calcyclin. Recurrent cholesteatomas can be identified from nonrecurrent ones on the basis of three features, namely, the level of apoptotic cells, the way in which the apoptotic cells are distributed (i.e., homogeneously vs. heterogeneously), and the percentage of calcyclin-positive cells. The present data emphasize the existence of distinct subgroups of cholesteatomas identifiable at both cell kinetic and differentiation levels. Some of the biological variables used here to identify distinct biological subgroups of cholesteatomas in turn enabled some biological variables to be identified, so making it possible to classify the cholesteatomas in terms of recurrence versus nonrecurrence.

Ganglioglioma

Ganglioglioma is a rare, mixed neuronal-glial neoplasm of the central nervous system that occurs in young patients and has a benign clinical course. To define the immunophenotypic and morphologic features of ganglioglioma precisely, 27 specimens were studied by routine histochemistry, 21 specimens by immunochemistry, and 14 specimens were examined at the ultrastructural level. The age of the 27 patients, 14 males and 13 females, ranged from 3 to 52 years (mean, 22 years). The most commonly affected site was the temporal lobe (13 patients). Three patients experienced a local recurrence. Microscopically, the tumors were comprised of well differentiated, somewhat abnormal neurons as well as glial cells, the latter including astrocytes of fibrillary (59%) and pilocytic (41%) type. Scant mitotic activity was observed in 2 tumors (7%). Glial cells of all tumors were immunoreactive for glial fibrillary acidic protein, S-100 protein, and vimentin. Ki-67 labeling indices (LI) ranged from 0.6 to 10.5% (mean, 2.7%) and p53 LI from 1.1 to 42.4% (mean, 15.6%). Ki-67 and p53 LI in recurrent tumors were significantly higher than those of nonrecurrent ones (P = 0.036 and 0.026, respectively). No examples of anaplastic transformation were encountered. Immunohistochemically, many neuronal cells were positive for synaptophysin (100%), Class 3 beta-tubulin (100%), neurofilament protein (90%), and chromogranin A (86%), in addition to S-100 protein (71%) and, occasionally, vimentin (24%). Ultrastructural characteristics of neuronal cells included the presence of numerous, 100-230-nanometer dense core granules within both perikarya and cell processes, well developed rough endoplasmic reticulum, microtubules within cell processes, and synapses associated with clear vesicles. Astrocytic cells usually contained abundant intermediate filaments; their cell membranes, when abutting the stroma, were covered by basal lamina. Gangliogliomas are comprised of well differentiated neuronal cells and glial cells that are very often of pilocytic type. No cells with features intermediate between neurons and glia were observed. Neuronal cells are characterized by prominent neurosecretory features distinct from those of normal neurons in the central nervous system. Higher Ki-67 and p53 LI may indicate more aggressive behavior.