Perception of young adults toward hookah use in Mumbai.

BACKGROUND: The use of tobacco has been on the rise globally including in India, posing a grave public health problem. Recently, tobacco use through hookah smoking has increased among young adults in India, Middle East, Southwest Asia, Africa, Europe and North America. Hookah prevalence of 0.4‑15% has been reported in India. AIM: The aim of the study was to understand perception of hookah use among young adults in Mumbai. MATERIALS AND METHODS: A total of 500 college students, with/without hookah habit, were given a self‑administered questionnaire to indicate their perception of hookah use, using yes/no responses. The responses were analyzed in the users/non‑users and considered significantly different at P < 0.05. RESULTS: Responses were received from 122 hookah users and 325 non‑users. The perception of hookah use between users and non‑users and males and females, showed significant differences (P < 0.05), with respect to hookah being injurious to health, causes cancer, is addictive, influence of a close friend, flavors, curiosity toward hookah use and willingness to prepare hookah at home. Whereas, differences in the groups perception of hookah as safer than cigarettes, harmful air quality, ambience, cool look and means of socializing, was not observed. CONCLUSION: The perception of young adults in Mumbai, toward hookah use, indicates an increased trend to use hookah. We recommend deterrents for hookah use by display of health warnings on hookah assembly and the tobacco products, implementation of government policies on hookah and tobacco use and punitive measures for offenders.

RET gene mutations and polymorphisms in medullary thyroid carcinomas in Indian patients.

Germline mutations of RET gene are pathognomonic of multiple endocrine neoplasia (MEN; MEN 2A/MEN 2B) and familial medullary thyroid carcinoma (FMTC), constituting 25% of medullary thyroid carcinomas (MTCs). We investigated RET gene mutations and polymorphisms at exons 10, 11, 13, 14, 15 and 16 in 140 samples, comprising 51 clinically diagnosed MTC patients, 39 family members of patients and 50 normal individuals. The method of choice was PCR and direct nucleotide sequencing of the PCR products. RET gene mutations were detected in 15 (29.4%) patients, with MEN 2A/FMTC in 13 patients and MEN 2B in 2 patients. Further, 39 family members of seven index cases were analysed, wherein four of the seven index cases showed identical mutations, in 13 of 25 family members. We also examined single nucleotide polymorphisms (SNPs) in RET gene exons in 101 unrelated samples. Significant differences in the allelic frequencies of SNPs at codons 691, 769, 836 and 904 between patient and control groups were not observed. However, SNP frequencies were significantly different in the Indian group as compared with other European groups. We identified two novel, rare and unique SNPs separately in single patients. Our study demonstrated presence of MEN 2A/MEN 2B/FMTC-associated mutations in accordance with the reported literature. Thus, RET gene mutations in exons 10, 11, 13, 14, 15 and 16 constitute a rapid test to confirm diagnosis and assess risk of the disease in familial MEN 2A/MEN 2B/FMTC.

Induction of lymphomas on implantation of human oral squamous cell carcinomas in nude mice.

Cancer cells from five oral cancer patients and pleomorphic adenoma cells from one individual were inoculated as single cell suspension into subcutis of 30 Swiss nude mice and tail vein of additional 30 mice. Further, tumor tissue pieces from three oral cancer patients were xenografted s.c. in 18 nude mice, and 10 mice were kept as controls. In animals implanted with tumor pieces, 7/18 (39%) mice, developed squamous cell carcinoma at the site of inoculation within 8-15 days, while tumors were not observed in mice inoculated with single cell suspension, up to 60/90 days. In 8/68 (12%) mice, white foci were observed in several tissues, with hepatomegaly and splenomegaly noted in 27/68 (39%) mice. Histopathological examination of various tissues revealed presence of large cell lymphoma in several organs in 14/68 (21%) mice. No regional or distant metastasis of the implanted oral tumor cells was detected. Mice injected with cells from pleomorphic adenoma, also demonstrated large cell lymphoma in 2/10 (20%) mice, whereas none of the 10 control animals showed any gross abnormalities or microscopic abnormalities in several organs. 2/16 (12%) lymphomas exhibited positive reaction with mouse B cell antibodies illustrating the murine origin of the lymphomas, and these were immunophenotyed as B cell lymphomas. The lymphomas were also examined with mouse T cell antibodies and none reacted positively with the mouse T cell antibodies. The lymphomas also failed to react with human T cell, B cell and human Leucocyte common antigen (LCA) antibodies, indicating that the induced lymphomas were not of human origin. The tumor specimens from seven of eight oral cancer patients and the pleomorphic adenoma patient induced lymphomas in nude mice. Thus it appears that xenografting oral tumor cells into nude mice may cause induction of the murine lymphomas, and this needs further investigation.

Loss of p53 gene as a biomarker of high risk oral leukoplakias.

We have investigated loss of heterozygosity of p53 tumor suppressor gene in Indian oral cancer patients, individuals with premalignant leukoplakia lesions, and corresponding normal mucosa, to study the status of p53 alleles in oral cancer pathogenesis. Fifty oral cancers, and 42 oral leukoplakia lesions and corresponding clinically normal oral mucosa from 18 individuals, were analysed. Peripheral blood cells (PBCs) from all the individuals and 47 normal healthy volunteers were also included in the study. Polymerase chain reaction(PCR) of p53 Exon4, followed by restriction enzyme digestion with AccII due to the enzyme polymorphic site at Exon4 codon72, was used to detect homozygosity/heterozygosity of p53 alleles, and compared with the allelic pattern in the corresponding PBC. The PCR product subjected to AccII digestion detected 259 bp, 160/99 bp fragments indicating heterozygosity of p53 alleles in 69% of the 139 individuals. On comparison of the p53 allelic distribution in the lesions or tumour tissues, and corresponding PBC, LOH was observed in 20.5% oral tumors and 22% leukoplakias. However, there was no evidence of LOH in the clinically normal mucosa available from 16 individuals with leukoplakia. Our studies demonstrated LOH of p53 allele in early and advanced stages of oral cancers, as well as leukoplakias, perhaps indicating p53 LOH as one of the early events in oral carcinogenesis. Thus, p53 LOH may be useful as a biomarker in defining a certain population of high risk leukoplakias that may progress to oral cancer.

Restriction fragment length polymorphisms of the human N-myc gene in normal healthy individuals and oral cancer patients in India.

Southern blot hybridization with N-myc oncogene probes coding for different regions of the N-myc gene demonstrated three polymorphic restriction sites in the Indian population. The SphI and PvuII polymorphic pattern due to the SphI polymorphic site in the second intron and the PvuII polymorphic site in the 3'-region of the human N-myc oncogene respectively, was similar to that reported in the Japanese population. The allelic frequency distribution for SphI polymorphism did not differ significantly for the S1 and S2 alleles representing presence (allele S1) or absence (allele S2) of a SphI site. However, the allelic frequency distribution was distorted in the case of PvuII polymorphism, as the frequency of P1 allele (0.7) indicating presence of PvuII site, was higher than the P2 allele (0.3) indicating absence of PvuII site, in the Indian population. An additional polymorphic HindIII site localised in the second intron of the N-myc gene was also observed in both the Indian oral cancer patients and the normal healthy individuals, indicating that this RFLP was not tumor associated and may perhaps represent N-myc alteration in the Indian population.