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.
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An empirical review on the resistance mechanisms of epidermal growth factor receptor inhibitors and predictive molecular biomarkers in colorectal cancer Sankha Bhattacharya Critical Reviews in Oncology/Hematology.2023; 183: 103916. CrossRef
Background The low prevalence of human papillomavirus (HPV) DNA and mRNA in biopsy samples of Filipinos with head and neck squamous cell carcinoma (HNSCC) has been reported previously. Here, the HPV serologic profiles of HNSCC cases were analyzed and associated with life-style and sexual practices.
Methods Serum samples were collected between May 2012 and September 2013 from HNSCC patients (n = 22) in the northwest region of the Philippines, and age- and sex-matched clinically healthy controls. Antibodies to capsid and early oncoproteins of HPV16, 18, 31, 33, 45, 52, 58, 6, and 11 were analyzed using multiplex serology.
Results Most of the cases were males with tumors of the oral cavity or larynx. Two of the cases tested positive for at least one of the early oncoproteins (E6, E7, E1, and/or E2) of HPV16, and 11 did not display reactivity to any HPV early or late oncoproteins. Of the controls, four tested positive for at least one of the HPV16 early oncoproteins, and 10 were non-reactive to all HPV types. Titers to HPV16 E6 or E7 of the seropositive cases and controls were considerably lower than those typically observed in economically developed countries.
Conclusions The low HPV titers seen here are consistent with the results of molecular analyses for this population. Hence, the seropositivity of some of the HNSCC cases is likely an indication of prior exposure to the virus and not the presence of HPV-driven tumors.
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Social determinants of sex disparities in cancer in Southeast Asia Ma. Veronica Pia N. Arevalo, Ethan Angelo S. Maslog, Katherine Donatela Manlongat, Eric David B. Ornos, Imjai Chitapanarux, Michelle Ann B. Eala, Edward Christopher Dee iScience.2023; 26(7): 107110. CrossRef