Oral mucosa and lung cancer: Are genetic changes in the oral epithelium associated with lung cancer?

Aim: To compare genetic aberrations in the oral epithelium of lung cancer patients with those without cancer.Subjects and Methods: Buccal smears were performed to collect oral epithelium from each of the participants (smoker cancer patients n = 50, smoker control subjects n = 40, and nonsmoker control subjects n = 25). Cytogenetic changes in the samples were detected by micronuclei assay, whereas p53 and murine double minute 2 (MDM2) polymorphisms were genotyped using polymerase chain reaction‑restriction fragment length polymorphism.Results: p53 codon 72 polymorphism was seen in 44% of cancer patients versus 12.5% in smokers and 12% in nonsmokers of the control group. Similarly, MDM2 single nucleotide polymorphism 309 polymorphism was seen in 34% of patients with lung cancer as opposed to 12.5% of smokers (P = 0.038) and 8% of nonsmokers (P = 0.019) of the control group.Conclusion: A higher proportion of individuals with lung cancer demonstrate genetic damage to oral mucosa compared to those without cancer.Keywords: Lung cancer, murine double minute 2, oral epithelium, p53, polymorphis

Craniodental Allometry, Prenatal Growth Rates, and the Evolutionary Loss of the Third Molars in New World Monkeys

A growing body of literature demonstrates that genetic patterning mechanisms underlie the relative proportions of the mammalian postcanine dentition with the third molar being key to understanding variation within the molar row. With this relatively recent insight, there has been renewed interest in mammalian taxa that have lost the third molars. Within platyrrhines, the marmosets and tamarins (Callitrichidae family) are characterized by small body size, claw‐like nails, twinning, and reduced molar number. Small body size is hypothesized to have resulted in the third molar being crowded out of the jaws leading to its evolutionary loss in this family. To further explore this hypothesis, we measured the cranium and dentition of 142 individuals spanning all five platyrrhine families. These data reveal that callitrichids have a significantly smaller proportion of mandibular postcanine tooth row length relative to other platyrrhines, refuting the “crowding out” hypothesis. However, postcanine tooth row length is significantly correlated with mandibular length and cranial length (P < 0.01) across all platyrrhines providing evidence for a strong allometric association between postcanine tooth row length and body size more generally. The small body size that characterizes callitrichids results in part from slower prenatal growth rates. Given the allometric relationship between postcanine tooth row length and body size, reported here and in previous studies, we hypothesize that the evolutionary loss of the third molars in callitrichids results from the inhibition of third molar development as a consequence of the slower prenatal growth rates associated with small body size in this family. Anat Rec, 2018. © 2018 Wiley Periodicals, Inc