In many cervical cancers, human papillomavirus type 16 (HPV-16) DNA genomes are found to be integrated into the host chromosome. In this study, we demonstrate that integration of HPV-16 DNA leads to increased steady-state levels of mRNAs encoding the viral oncogenes E6 and E7. This increase is shown to result, at least in part, from an increased stability of E6 and E7 mRNAs that arise specifically from those integrated viral genomes disrupted in the 3' untranslated region of the viral early region. Further, we demonstrate that the A+U-rich element within this viral early 3' untranslated region confers instability on a heterologous mRNA. We conclude that integration of HPV-16 DNA, as occurs in cervical cancers, can result in the increased expression of the viral E6 and E7 oncogenes through altered mRNA stability.Human papillomaviruses (HPVs) are small DNA viruses that infect epithelial cells. About 70 different genotypes have been identified to date, among which only a subset are associated with cervical cancers. More than 90% of cervical cancers contain these "high-risk" HPVs . In these cancers, two viral transforming genes, E6 and E7, are consistently expressed (1). The E6 and E7 proteins have been shown to interact with and inactivate the tumor-suppressor gene products p53 and pRb, respectively (34), and to immortalize human epithelial and fibroblastic cells as well as rodent fibroblasts (2-4). In transgenic mouse systems, expression of these genes leads to tumor formation (5)(6)(7)(8). These studies have demonstrated the likely importance of E6 and E7 in cervical carcinogenesis.The viral DNA genome of HPV-16 or -18 is often found integrated into the host chromosomes in cervical cancers (9)(10)(11). This viral DNA integration has been hypothesized to result in increased expression of E6 and E7 (12). To test this hypothesis, we have isolated a series of human cervical epithelial cell populations that harbor either extrachromosomal or integrated HPV-16 DNA (35). These cell populations were derived from a parental cell population, W12, that had been established from an HPV-16-positive cervical biopsy (13).Using these reagents, we have demonstrated that HPV-16 DNA integration correlates with increased expression of the viral E7 protein and with a selective growth advantage over cells harboring extrachromosomal HPV-16 DNA (35).In the current study, we have sought to define a mechanism by which integration leads to increased expression of papillomaviral transforming genes. We demonstrate that the high levels of E7 protein seen in the integrated clones correlate with increased steady-state levels of E6-and E7-specific mRNAs, at least in part as a result of changes in their stability. This increased stability appears to be the result of the integrative The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. §1734 solely to indicate this fact. S1 Nuclease Mapping Analysis. The E6/E7-specific cDN...

Integration of human papillomavirus type 16 (HPV-16) DNA into a host chromosome has been hypothesized to result in altered expression of two viral transforming genes, E6 and E7, in cervical cancers. In order to investigate the role that changes in viral genomic state and gene expression play in cervical carcinogenesis, we have derived clonal populations of human cervical epithelial cells which harbor multiple copies of either extrachromosomal or integrated viral DNA. The clonal populations harboring extrachromosomal HPV-16 DNA stably maintained approximately 1,000 viral copies for at least 15 passages (approximately 100 cell doublings), which contrasted with the unstable HPV-16 replicons in the parental counterpart. In the clonal populations harboring integrated viral DNA, 3 to 60 copies of HPV-16 DNA were found integrated in either of two forms: type 1, in which all the copies of HPV-16 DNA were disrupted in the E2 open reading frame upon integration, and type 2, in which intact viral copies were flanked by disrupted viral copies and cellular sequences. Despite the lower HPV-16 DNA copy number, the clonal populations with integrated viral DNA had levels of E7 protein that were in most cases higher than those found in the clonal populations harboring extrachromosomal viral DNA. Irrespective of viral genomic state, the clonal populations were capable of undergoing terminal differentiation and unable to form colonies in soft agar, which is indicative of the nontumorigenic nature of these cells. Importantly, a cell population with integrated viral DNA was found to outgrow another with extrachromosomal DNA when these cells were cocultured over a period of time. Thus, integration of human papillomaviral DNA correlates with increased viral gene expression and cellular growth advantage. These observations are consistent with the hypothesis that integration provides a selective advantage to cervical epithelial precursors of cervical carcinoma.

A stretchable multisensor system is successfully demonstrated with an integrated energy-storage device, an array of microsupercapacitors that can be repeatedly charged via a wireless radio-frequency power receiver on the same stretchable polymer substrate. The integrated devices are interconnected by a liquid-metal interconnection and operate stably without noticeable performance degradation under strain due to the skin attachment, and a uniaxial strain up to 50%.

Two-photon absorption (TPA) cross sections of four representative series of octupolar molecules are theoretically investigated. The general structure--TPA-property relationship is described by using the effective four-state valence-bond three-charge-transfer model. As the charge-transfer character of the ground electronic state increases due to the strong donors or acceptors, (i) the transition dipole matrix elements between the ground and 2-fold degenerate excited states increase, (ii) the energy gap decreases, and consequently (iii) the TPA transition amplitude monotonically increases. Thus, the design strategy to maximize the TPA cross section of the octupolar molecule is established. On the basis of the four-state model, the first hyperpolarizability of the octupolar molecule is found to be linearly proportional to the TPA cross section. This theoretical relationship is confirmed by using the ab initio calculation results. The Hammett correlation analysis of the TPA cross section and first hyperpolarizability is also presented.

Two-photon absorption (TPA) properties of 1,3,5-tricyano-2,4,6-tris(styryl)benzene derivatives have been investigated. Comparison of the absorption and fluorescence spectra reveals that these compounds show large Stokes shifts, which increase gradually as the conjugation length increases. One-photon absorption and excitation spectra are similar except that the latter exhibit several peaks near lambda(max). It is also found that the one- and two-photon-induced fluorescence excitation spectra are quite similar, which indicates that the one- and two-photon allowed-excited states are the same. The peak TPA cross section values (delta(max)) measured with nanosecond pulses by the two-photon-induced fluorescence method are in the range (50-2620) x 10(-50) cm4 s/photon. The delta(max) value increases as the donor strength and conjugation length increase. A linear relationship is observed between delta(max) and beta, and this delta-beta relationship is found to serve as a useful synthetic strategy for the design of novel TPA dyes with the octupolar structure.