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B S Mathew

Publications and source records attributed to B S Mathew.

10 recordsLinked to original sources
PubMed2001

Apoptosis, angiogenesis and proliferation: trifunctional measure of tumour response to radiotherapy for oral cancer.

Local recurrence is a significant problem following radiotherapy in oral carcinoma and hence there is a paramount need for predictive markers. This study therefore analysed the predictive value of pre-treatment status of angiogenesis, apoptosis, expression of apoptosis regulatory p53, bax and bcl-2 proteins as well as tissue proliferation in relation to tumour response to radiotherapy. Sixty-nine histologically defined invasive carcinoma lesions were included in the study. Extent of apoptosis was defined morphologically and by the TUNEL (Tdt-mediated dUTP biotin nick end labelling) assay. Expression of apoptosis regulatory p53, bax and bcl-2 proteins were evaluated by immunocytochemistry. Mutant p53 protein was detected using a mutant p53-specific ELISA. The extent of tissue proliferation was evaluated by cyclin D1 expression. Angiogenesis was evaluated by CD34 antigen expression. All patients were treated with radical radiotherapy and followed up for 36 months. High levels of p53 protein detected by immunocytochemistry were found to be associated with poor response to treatment or disease relapse. Detection of mutant p53 protein also showed significant association with poor prognosis. Low levels of angiogenesis had a correlation with recurrence status. Tumours showing less vascularisation as well as increased apoptosis had a poor prognosis. Expression of p53 and bcl-2 proteins showed direct correlation with angiogenesis. There was no correlation between clinical status and any of the experimental parameters with histopathological grades of invasive lesions. Presence of mutant p53 protein is suggestive of poor tumour response to radiotherapy. Expression of p53 and increased apoptosis in less vascularised tumours is associated with treatment resistance. A predictive assay based on these results designed to analyse individual tumour samples showed presence of apoptotic cells near the vasculature to be indicative of good prognosis, while absence of apoptotic cells or highly proliferative cells and/or expression of bcl-2 protein in cells around the vasculature to be an indicator of poor prognosis.

Aged↗
PubMed1999

De novo programmed cell death in oral cancer.

AIM: The importance of programmed cell death or apoptosis in the maintenance of tissue homoeostasis and the pathogenesis of oral cancer was analysed in relation to apoptosis regulatory proteins, tissue proliferation and tumour histology. METHODS AND RESULTS: The extent of apoptosis was defined by morphological criteria and the TUNEL (terminal deoxy nucleotidyl transferase-mediated dUTP biotin nick end labelling) assay. p53, bax, bcl-2 and cyclin D1 expression was evaluated by immunocytochemistry. The presence of mutant p53 was analysed using a mutant p53-specific ELISA. An inverse correlation was observed between TUNEL reactivity and histology of the lesion (r = -0.555, P = 0.0001). There was also correlation between TUNEL reactivity and immunoreactivity of apoptosis regulatory proteins. p53 (r = 0.641, P = 0.00023), bcl-2 (r = -0.642, P = 0.00014) and bax (r = 0.651, P = 0.00002). The presence of mutant p53 protein showed an inverse correlation to the extent of apoptosis (r = - 0.301, P = 0.00063). Significant correlation was evident between the bax/bcl-2 ratio and TUNEL (r = 0.652, P = 0.00001) as well as between cyclin D1 and TUNEL reactivity (r = 0.577, P = 0.00001). CONCLUSIONS: Results from this study suggest that apoptosis decreases as histological abnormality increases. Apoptotic regulatory proteins are also altered in a histologically dependent manner. Deregulated proliferation occurs simultaneously with decreased apoptosis during tumour progression in the oral mucosa.

Adult↗
PubMed1998

Angiogenesis during tumor progression in the oral cavity is related to reduced apoptosis and high tumor cell proliferation.

Angiogenesis, the growth of new blood vessels, is believed to aid tumor progression and metastasis. Tumor progression is also influenced by the extent of proliferation and apoptosis. This study, therefore, analyzed in lesions of the oral cavity, the significance of angiogenesis in relation to apoptosis, expression of apoptosis regulatory p53, bax and bcl-2 proteins as well as tissue proliferation defined by cyclin D1 expression. Results from this study suggest that angiogenesis increases as histological abnormality increases in the oral mucosa. The expression of apoptosis regulatory proteins also appears to be altered in a histologically dependent manner. The correlation seen between CD34 expression, cyclin D1 and TUNEL reactive cells suggests that increased angiogenesis, decreased apoptosis and deregulated proliferation occur simultaneously during tumor progression in the oral mucosa. Presence of a mutant p53, increased bcl-2 expression and altered bax expression are also involved in this complex process.

Antigens, CD34↗
PubMed1998

Renal metastasis from squamous cell carcinoma of the lung.

Symptomatic renal metastases from primary malignancy elsewhere in the body is an uncommon feature in disseminated cancer. Postmortem diagnosis is more frequent. A case is reported here of a patient with renal metastasis from lung carcinoma who presented with haematuria.

Carcinoma, Squamous Cell↗
PubMedDate not supplied

Malignant phyllodes tumor.

The study aims to evaluate the survival and prognosis of patients with malignant phyllodes tumor. Between 1982 and 1998, 37 women with malignant phyllodes tumor were treated at the Regional Cancer Center, Trivandrum. Twelve patients were recurrent. Survival was estimated using the Kaplan-Meier method. Patient, disease, and treatment factors were compared using log-rank test. The Cox-proportional hazard model was employed to identify the prognostic factors. Thirty-six patients had surgery. Twenty-five patients received postoperative radiotherapy, and 2 received chemotherapy in addition. The median follow-up was 43 months (range 1-170 months). Eight patients failed locally, and 7 of these were successfully salvaged by surgery. The 5-year overall survival was 74.2% (95% CI, 0.44 to 0.89), whereas 5-year disease-free survival was 59.6% (95% CI, 0.39 to 0.7). The margin of surgical excision was found to be the only independent prognostic factor (p=0.003). However, patients with tumor size more than 5 cm (hazard ratio 2.9) were found to have increased hazard, whereas those receiving adjuvant radiotherapy (hazard ratio 0.6), married women (hazard ratio 0.4), and those women over the age of 35 years (hazard ratio 0.7) showed a decreased hazards. Cystosarcoma phyllodes is a rare malignancy of the female breast. Surgery with adequate margins is the primary treatment. Adjuvant radiotherapy appears to improve the disease-free survival.

Adult↗
PubMedDate not supplied

Testicular germ cell tumors in prepubertal children.

Pediatric testicular germ cell tumors are rare. Fifteen children, all less than 5 years of age, were evaluated and treated during February 1987 to July 1996. The median age was 18 months (range, 4-60 months). All were staged according to the Pediatric Oncology Group/Children's Cancer Study Group staging system. Seven patients had stage III disease. Histologically, 9 patients had pure endodermal sinus tumor, 1 had endodermal sinus tumor with embryonal carcinoma, 1 had embryonal carcinoma alone, 2 had immature teratoma, and 2 had mature teratoma. Six children were kept on surveillance. All others received chemotherapy with cisplatin, bleomycin, and vinblastine. The 10-year actuarial overall survival rate was 86.7%.

Antineoplastic Combined Chemotherapy Protocols↗
PubMedDate not supplied

Primary choriocarcinoma of the ovary. Report of two cases.

Primary choriocarcinoma of the ovary (PCO) is rare. This can be gestational (GCO) or nongestational (NGCO) in origin. It is difficult to differentiate between CGO and NGCO. NGCO carries a worse prognosis than GCO. We present two cases of metastatic GCO who were treated successfully with combination chemotherapy and are alive and disease free at the time of reporting.

Adult↗
PubMedDate not supplied

A six-hour extrapolated sampling strategy for monitoring mycophenolic acid in renal transplant patients in the Indian subcontinent.

BACKGROUND: Therapeutic drug monitoring for mycophenolic acid (MPA) is increasingly being advocated. The present therapeutic range relates to the 12-hour area under the serum concentration time profile (AUC).However, this is a cumbersome, tedious, cost restricting procedure. Is it possible to reduce this sampling period? AIM: To compare the AUC from a reduced sampling strategy with the full 12-hour profile for MPA. SETTINGS AND DESIGN: Clinical Pharmacology Unit of a tertiary care hospital in South India. Retrospective, paired data. MATERIALS AND METHODS: Thirty-four 12-hour profiles from post-renal transplant patients on Cellcept were evaluated. Profiles were grouped according to steroid and immunosuppressant co-medication and the time after transplant. MPA was estimated by high performance liquid chromatography with UV detection. From the 12-hour profiles the AUC up to only six hours was calculated by the trapezoidal rule and a correction factor applied. These two AUCs were then compared. STATISTICAL ANALYSIS: Linear regression, intra-class correlations (ICC) and a two-tailed paired t-test were applied to the data. RESULTS: Comparing the 12-hour AUC with the paired 6-hour extrapolated AUC, the ICC and linear regression(r2) were very good for all three groups. No statistical difference was found by a two-tailed paired t-test. No bias was seen with a Bland Altman plot or by calculation. CONCLUSION: For patients on Cellcept with prednisolone +/- cyclosporine the 6-hour corrected is an accurate measure of the full 12-hour AUC.

Adolescent↗