ABSTRACT
Background@#Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA) mutations have been reported in many cancers, including head and neck squamous cell carcinoma (HNSCC). The frequency of these mutations varies among tumor locations and might be relevant to treatment outcomes among HNSCC. In this study, we examined the frequency of PIK3CA mutations in the different subsites of HNSCC. @*Methods@#Ninety-six fresh biopsy specimens were investigated for mutations in PIK3CA exons 4, 9, and 20 using allele-specific real-time polymerase chain reaction. Patient characteristics and survival were analyzed and compared between specimens with or without PIK3CA mutations. @*Results@#The study included primary tumors originating from the oral cavity (n=63), hypopharynx (n=23), and oropharynx (n=10). We identified mutations in 10.4% of patients (10 of 96 specimens). The overall mutational frequency was 17.4% (4/23) and 9.5% (6/63) in the hypopharynx and oral cavity, respectively. No patients with oropharyngeal carcinoma had mutations. Among the 10 mutant specimens, five were missense mutations (exon 9 [E545K] in two samples and exon 20 [H1047R] in three samples) and five were silent mutations in exon 20 (T1025T). Mutations were not found in exon 4. Among 84 patients with available clinical data, we found no significant differences in clinical characteristics and survival based on the presence or absence of PIK3CA mutations. @*Conclusions@#The results indicate that PIK3CA mutations are involved in HNSCC carcinogenesis, and the hypopharynx should be considered a primary site of interest for future studies, particularly in Southeast Asian populations.
ABSTRACT
Background: Charcoalproduction workers work in conditions involving a high level of wood smoke. Wood smoke exposure in humans causes respiratory symptoms.Objective: To study the pulmonary function and respiratory symptoms of charcoal plant workers, andcompare their pulmonary function with rubber planters.Materials and methods: A comparative study was conducted to compare the pulmonary function andrespiratory symtoms between charcoal workers and rubber planters.Results: This study examined a total of 50 charcoal workers and 50 rubber planters. The charcoal workers were found to have signifi cantly more coughs (84%), sputum production (82%), dyspnea (42%), wheezing (32%), nasal irritation (80%), and nasal congestion (26%) than the control group. The mean + SD values of ratio between the forced expiratory volume in one second and forced vital capacity (FEV1/FVC%) and Peak expiratory fl ow (PEF%) as determined by spirometer test in the charcoal workers were significantly lower than in the control group. The mean + SD value of Peak expiratory fl ow (PEF) by peak fl owmeter test in the charcoal workers.Conclusion: The present study showed an association between wood smoke exposure in charcoal workers with respiratory symptoms and decreased pulmonary function, because the charcoal production process requires lengthy periods of curing during which a large amount of wood smoke is generated, which is breathed by the workers.