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Biomedical subjects

V G Chellam

Publications and source records attributed to V G Chellam.

At least 19 recordsLinked to original sources
PubMed2002

Apoptosis in epithelial ovarian tumors.

It is now recognized that apoptosis plays an important role in the pathogenesis of tumors. This study evaluated the extent of apoptosis in different grades of ovarian tumors and correlated it with the expression of apoptosis regulatory genes, p53 and bcl-2 and with the total proliferative compartment of the tumor defined by the expression of the proliferating cell nuclear antigen (PCNA). Apoptosis was evaluated by the TUNEL (Tdt-mediated dUTP biotin nick end labelling) assay. Expressions of p53, bcl-2 and PCNA were analyzed by immunohistochemistry. A negative correlation was observed between the expression of bcl-2 and the extent of apoptosis (r = -0.3336, p = 0.019). P53 accumulation directly correlated with the extent of apoptosis (r = 0.485, p = 0.00041). The labelling index of PCNA also showed correlation with expression of p53 (r = 0.49, p = 0.00000). Apoptosis was significantly higher in poorly differentiated tumors when compared to the well- and moderately-differentiated tumors (r = 0.49152, p = 0.00034). Such poorly-differentiated tumors also showed high p53 overexpression and loss of bcl-2 expression. The present study thus provides evidence that dysregulation of apoptosis and its regulatory genes is associated with increasing malignant potential and may thus contribute to the pathogenesis of ovarian tumors.

Adenocarcinoma, Mucinous↗
PubMed2000

In situ apoptosis in the thyroid.

Recent evidence has emphasized the importance of programmed cell death, or apoptosis, in the maintenance of tissue homeostasis and pathogenesis of tumors. This study analyzed the significance of apoptosis in relation to the expression of p53 and bcl-2 proteins, tissue proliferation defined by Ki-67 expression, and tissue histology in thyroid tissue. Extent of apoptosis was defined by morphological criteria and the terminal deoxynucleotidyl transferase-mediated deoxy uridine triphosphate (dUTP) biotin nick end labeling (TUNEL) assay. Immunocytochemistry was performed for p53, bcl-2, and Ki-67 expression. There was good correlation between TUNEL-reactive cells and morphological evaluation criteria for apoptosis. The extent of apoptosis was significantly associated with the type of thyroid lesion (r = 0.66990, p = 0.000012), both proliferative (namely multinodular goiter) and neoplastic (benign and malignant). A higher extent of apoptosis was evident in medullary and anaplastic carcinomas. Apoptosis also correlated to p53 protein accumulation (r = 0.485, p = 0.00041) and Ki-67 immunoreactivity (r = 0.435, p = 0.001). An inverse correlation was observed between bcl-2 expression and the extent of apoptosis (r = -0.33369, p = 0.01912). A direct correlation was also observed between p53 expression and Ki-67 immunoreactivity (r = 0.623, p = 0.0002). By inhibiting apoptosis, bcl-2, may cause a shift in tissue kinetics toward the preservation of genetically aberrant cells, thereby facilitating tumor progression. These results imply that rapidly proliferating tumors appear to have a high cell turnover state in which there may be increased chance of apoptosis among the proliferating cells. The ability of apoptosis to occur in the presence of a possibly mutant p53 protein suggest the existence of at least two p53 dependent apoptotic pathways, one requiring activation of specific target genes and the other independent of it. However, keeping in mind the limited number of subjects studied in each subgroup and the rather low correlation coefficients, these possibilities would have to be substantiated in a larger study population.

Adult↗
PubMed1999

Disseminated Langerhans cell histocytosis in children: treatment outcome.

Langerhans cell histiocytosis is an interesting disorder with a variety of presentations and variable outcomes. This study evaluates response to treatment, recurrence, and survival in disseminated Langerhans cell histiocytosis treated at Regional Cancer Centre, Trivandrum, India from 1983 through 1994. Thirty-five patients with disseminated Langerhans cell histiocytosis were seen. Six had group A disease, 21 had group B disease, and eight had group C disease. In group A, five of six patients are disease free at a median follow-up of 48 months. Two had recurrence after initial treatment, which was salvaged. In group B, 13 of 15 patients had complete response after chemotherapy, nine of whom experienced recurrence later. Three of five patients who received irradiation alone experienced recurrence. One died of progressive disease. Two patients were lost to follow-up. Seventeen of 20 are alive with median follow-up of 67 months. In group C, one of eight patients are alive after multiple recurrences. Of the surviving patients, 29% had significant sequelae. In summary, group A and B patients do well with treatment, and most of the recurrences can be salvaged. A significant proportion of patients have sequelae. Newer aggressive protocols must be developed for treating group C patients. Measures to prevent sequelae must also be developed.

Adolescent↗
PubMed1999

Langerhans cell histiocytosis in children less than 2 years of age.

OBJECTIVE: To study the clinical profile and outcome of langerhans cell histiocytosis in children upto 2 years of life. DESIGN: Retrospective analysis. METHODS: Medical records of Children upto 2 years of age with a diagnosis of langerhans cell histiocytosis (LCH) were analyzed. Their clinical pattern, treatment modalities and outcome were studied. The patients Were categorized into 2 groups according to their clinical presentation: (i) Subject without organ dysfunction; and (ii) cases with organ dysfunction. Treatment considered of surgical intervention, radiotherapy, chemotherapy or combination of all these modalities depending upto the extent of disease. RESULTS: There were 20 children upto 2 years of age with histiocytosis during the 12 year period (January 1983 - December 1994). The median age at diagnosis was 18 months (range 52 days - 24 months). Of the twenty patients,13 patients didn't have organ dysfunction and 7 had organ dysfunction. Out of the 13 children without organ dysfunction eleven patients received treatment and all of them are alive free of disease with a median follow up of 62 months. But all children with organ dysfunction succumbed to disease within a few weeks. CONCLUSION: Children under 2 years of age with localised and or multifocal LCH without organ dysfunction have a good prognosis and they should not be exposed to aggressive form of treatment. All children with organ dysfunction require multi-agent chemotherapy.

Age Factors↗
PubMed1998

Spontaneous programmed cell death in infiltrating duct carcinoma: association with p53, BCL-2, hormone receptors and tumor proliferation.

Recent evidence has emphasized the importance of programmed cell death or apoptosis in the maintenance of tissue homeostasis and pathogenesis of tumors. This study, analyzed in breast cancer, investigates the significance of apoptosis in relation to the expression of p53 and bcl-2 proteins, tissue proliferation defined by Ki-67 expression, hormone receptors and tumor grade. The extent of apoptosis was defined by morphological criteria and the TUNEL (Tdt-mediated dUTP biotin nick end labelling) assay. Immunocytochemistry was performed for p53, bcl-2, estrogen receptor, progesterone receptor and Ki-67 expression. Mutant p53 protein was detected using a mutant specific ELISA. Immunoreactivity of p53 significantly correlated with the presence of mutant p53 protein detected by ELISA (r = 0.654, p = 0.00001). An inverse correlation was observed between bcl-2 expression and the extent of apoptosis (r = -0.33369, p = 0.01912). The extent of apoptosis directly correlated with p53 protein accumulation (r = 0.485, p = 0.00041), Ki-67 immunoreactivity (r = 0.435, p = 0.001), histopathological grade (r = 0.492, p = 0.0003), tumor size (r = 0.326, p = 0.023) and lymph node status (r = 0.287, p = 0.047). A direct correlation was also observed between p53 expression and Ki-67 immunoreactivity (r = 0.623, p = 0.0002). There was no statistically significant association between estrogen and progesterone receptor status and apoptosis. In addition, the TNM stage of the disease correlated with immunoreactivity of p53 (r = 0.572, p = 0.00012) and Ki-67 (r = 0.3744, p = 0.00818). Bcl-2, by inhibiting apoptosis, may cause a shift in tissue kinetics towards the preservation of genetically aberrant cells, thereby facilitating tumor progression. These results imply that rapidly proliferating tumors appear to have a high "cell turnover state" in which there may be an increased chance of apoptosis amongst the proliferating cells. The ability of apoptosis to also occur in the presence of mutant p53 protein suggests the existence of at least two p53-dependent apoptotic pathways, one requiring activation of specific target genes and the other independent of it.

Adult↗
PubMed1998

Pattern and outcome of neuroblastoma. A 10 year study.

OBJECTIVE: To determine the clinical pattern and outcome of children with neuroblastoma. DESIGN: Retrospective analysis. SETTING: Hospital based information from the case sheets. SUBJECTS: 91 children with age upto 14 years treated in the Regional Cancer Center, Trivandrum. METHODS: Clinical presentation, metastatic pattern and treatment outcome were analyzed. RESULTS: Median age of the study group was 2.5 years with a male:female ratio of 1.6:1. Fifteen per cent children had early stage disease and 85% advanced disease. Five children with stage III and 22 with stage IV disease did not receive may active treatment. The remaining 64 children were evaluated for this analysis with a survival rate of 25%. Two of the four (50%) stage I, four of the six (83.3%) stage II, five of the 18 (27.7%) stage III, three of the 32 (9%) stage IV and two of the four (50%) stage IVs patients are long term survivors. CONCLUSIONS: Majority of the children (> 80%) presented with advanced disease and outcome remained poor. Only 27% of stage III and 9% of stage IV patients are long term survivors in our series. In future, approaches to detect disease at an early stage and aggressive therapeutic strategies in selected patients may improve survival.

Adolescent↗
PubMed1997

p53 tumor suppressor protein and tissue proliferative fraction in infiltrating duct carcinoma.

BACKGROUND AND OBJECTIVES: Breast cancer continues to frustrate oncologists worldwide. In India, it is the second most common neoplasm among women and is increasing in incidence. Several molecular markers have been associated with a poor prognosis in patients with breast cancer, and the presence of these markers is often thought to provide information on the biological behavior of the malignant breast tumor. Much attention has recently been focused on the tumor suppressor gene p53. Mutation or alteration in this gene leads to the loss of negative growth regulation and hence to rapid cell proliferation. The present study was designed to evaluate the connection between expression of the p53 protein and its relation to the tissue proliferative compartment as measured by expression of the proliferating cell nuclear antigen (PCNA). METHODS: Expression of p53 and PCNA were detected by immunocytochemistry in paraffin-embedded sections of infiltrating duct carcinoma and control breast tissue (normal tissue and adenoma). RESULTS: A significant correlation was observed between expression of p53 and PCNA. A significant correlation was also observed between expression of p53 and grade of tumor and stage of disease. CONCLUSIONS: Our results support the hypothesis that accumulation of p53 is associated with a high tumor proliferation rate an association that might be expected in view of the role of wild p53 as a negative regulator of cell proliferation.

Adenoma↗
PubMed1997

Late recurrence of clear cell sarcoma of the kidney.

Clear cell sarcoma of the kidney (CCSK) is a rare pediatric neoplasm with particular propensity for bone metastasis that requires aggressive therapy. We report a patient with CCSK who was misreported as having Wilm's tumour at the time of initial diagnosis and received only minimal therapy. The disease recurred locally-after 8 years, with no evidence of distant metastasis. Important clinical and histologic features of CCSK are described, along with a review of the literature.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1997

Endodermal sinus tumors in the head and neck region.

Extragonadal germ cell tumors of the head and neck region account for only 5% of all benign and malignant germ cell tumors. Endodermal sinus tumors (EST) of the head and neck region are rare. We report three patients with EST of head and neck region over a period of 10 years; the primary sites of tumor were orbit, maxillofacial region and retroauricular region. Histopathological examination revealed malignant teratoma with predominant endodermal sinus pattern in two, and pure EST in one patient. Serum alpha fetoprotein (AFP) was elevated in all three patients. Two patients had initial surgery but did not receive adjuvant chemotherapy, as the parents refused it. Partial remission was achieved in the other patient who received chemotherapy (cisplatin, bleomycin and vinblastin) and the patient died of infection after four courses of chemotherapy.

Endodermal Sinus Tumor↗
PubMed1997

Expression of the antiapoptotic protein bcl-2 is not dependent on the tumor suppressor p53 protein in Indian breast carcinoma.

Tissue homeostasis and the maintenance of cell populations depend on a delicate balance between the rates of cell proliferation and cell death. Programmed cell death or apoptosis is believed to play a major role in physiological processes which, when defective, could contribute to the pathogenesis and progression of tumors. A role for altered programmed cell death in cancer stems from the description of alterations on tumor-associated genes involved in the regulation of apoptosis such as p53 and bcl-2. The p53 gene promotes apoptosis in cells with genetic damage, while bcl-2 is an antiapoptotic gene. It is therefore possible that the balance between p53 and bcl-2 may have significant implications for the pathobiology of breast cancer. This study was therefore undertaken to evaluate the expression of these two proteins with opposite functions and their relation to the total growth fraction of the tumor as measured by PCNA immunoreactivity. A significant correlation was observed between expression of p53 and PCNA. In contrast, bcl-2 expression did not correlate with the expression of p53. There was also no correlation observed between expression of bcl-2 and PCNA. A significant correlation was observed between expression of p53 and the grade of the tumor and stage of the disease. Our results thus support the hypothesis that accumulation of p53 is associated with a high tumor proliferation rate, an association that might be expected in view of the role of wild-type p53 as a negative regulator of cell proliferation. Another important observation was the lack of relationship between bcl-2 expression and PCNA immunoreactivity, supporting the hypothesis that bcl-2 is not a major regulator of proliferation.

Apoptosis↗
PubMed1997

Early diagnosis of bone biopsies--the role of sediment cytology.

This study analyses the role of the cytological examination of the sediment of the formalin in which bone biopsy specimens are received, in the early diagnosis of bone lesions. Of the one hundred lesions studied using this technique, twenty six of thirty three malignant lesions (seventy nine percent) could be diagnosed as malignant when relevant clinical and radiological data were considered. Sixty six benign lesions yielded sparsely cellular smears with benign cell. There was one false positive for malignancy. This simple rapid diagnostic technique can be used to advantage in the early diagnosis, and treatment planning of bone lesions.

Biopsy↗
PubMed1997

Tumor proliferative fraction in infiltrating duct carcinoma.

Deregulated cell proliferation is a key factor in malignancy and therefore may be of prognostic significance. Both Proliferating Cell Nuclear Antigen (PCNA) and silver binding Argyrophilic Nucleolar Organizer Regions (AgNORs) have been established as a valuable reflection of the tissue proliferative compartment and hence could be of value in studying the biologic behavior of malignant cells. In the present study, we evaluated the proliferative activity of 120 infiltrating duct carcinomas by analysing for PCNA and AgNOR expression in relation to pathologic variables. The AgNOR scores were significantly greater in the malignant tissue than in benign lesions. Expression of PCNA was also found to be increased in malignant breast tumors, when compared to controls. A strong positive correlation between PCNA immunoreactivity and AgNORs was evident. There was also a positive correlation between histologic grading and AgNOR score in breast cancer (r = 0.92, p = 0.000). Tumor with elevated AgNOR counts were often poorly differentiated. It is therefore apparent that evaluation of AgNORs and PCNA may help in the elaboration of histopathologic grading of infiltrating duct carcinoma and may be of prognostic significance.

Breast Neoplasms↗
PubMed1996

Chemotherapy in Hodgkin's disease.

OBJECTIVE: To assess the efficacy of primary chemotherapy in patients with clinically staged Hodgkin's disease. DESIGN: Non randomized study. SETTING: Pediatric Oncology Division of Regional Cancer Center. SUBJECTS: Twenty nine children with Hodgkin's disease. INTERVENTIONS: Chemotherapy was given to 21 patients whose parents agreed for the same. Sixteen children received COPP regimen and 5 received MOPP regimen. RESULTS: Complete remission was achieved in 19 patients. The relapse free survival and overall survival in these patients were 76% and 86%, respectively at 5 years. There was no death related to chemotherapy toxicity. CONCLUSION: Combination chemotherapy is an effective modality of treatment for children with Hodgkin's disease.

Adolescent↗
PubMed1994

Neuroblastoma with testicular metastasis. Review of literature and report of a case.

Eventhough neuroblastoma presents with wide spread tumour dissemination, metastasis to testes had rarely been reported. We report a case of Stage IV neuroblastoma who developed metastasis to both testes. He had massive infra-diaphragmatic disease with involvement of left supraclavicular lymph node at presentation. Treatment received by him was not adequate and five months later he developed metastasis to both testes. Hematogenous spread might have been the possibility in this case.

Abdominal Neoplasms↗
PubMed1989

Hepatoblastoma in siblings.

Two infants, a brother and sister, with hepatoblastoma of the right lobe of the liver were treated and are alive and lead normal lives. Only three other familial occurrences of this tumor have so far been documented.

Carcinoma, Hepatocellular↗
PubMed1989

Clear cell sarcoma of kidney (CCSK)--a clinicopathological study of 4 cases.

The clinical and histopathological features of four cases of clear cell sarcoma of kidney (CCSK) or Bone metastasising renal tumour of childhood (BMRTC) are presented. These cases were identified among 107 primary renal tumours in childhood over a period of 15 years (1973-1987) in the Trivandrum Medical College. Of the 107 cases 96 (89.7 percent) were nephroblastomas and 7 (6.6 percent) were Mesoblastic Nephromas. The incidence of Clear cell sarcoma was 3.7 percent. Abdominal mass and haematuria were the most common clinical features. All the four cases occurred in male children with no predilection for the right or the left kidney. At the time of presentation bone metastasis was not present in any of the four cases. Metastasis to scapula and skull was detected ten months after nephrectomy in one case. Of the four patients three were in stage I disease at the time of diagnosis. All the four cases showed the typical gross morphology and the classic microscopic pattern of Clear Cell sarcoma kidney. The treatment was similar in all the four cases with Surgery followed by radiotherapy and chemotherapy (Vincristine, Adriamycin Actinomycin D and cyclophosphamide). Only one of the four patients is alive and well 12 months after surgery. The literature is reviewed along with a discussion of the gross pathology, histology and histogenesis of clear cell sarcoma of kidney.

Child, Preschool↗
PubMed1988

Rhabdomyomatous dysplasia of the lung: a case report with review of the literature.

The occurrence of rhabdomyomatous dysplasia of the lung in a macerated term baby with multiple congenital anomalies is described. The hypoplastic right lung revealed abundant striated muscle in the alveolar septa and bronchial walls of the middle and lower lobes. A brief review of the literature is followed by a discussion of the pathogenesis of this rare pulmonary malformation.

Bronchopulmonary Dysplasia↗