1,454 research outputs found
Exploiting the circuit breaker cancer evolution model in human clear cell renal cell carcinoma
The incessant interactions between susceptible humans and their respective macro/microenvironments registered throughout their lifetime result in the ultimate manifestation of individual cancers. With the average lifespan exceeding 50 years of age in humans since the beginning of 2
Genomic landscape and evolution of metastatic chromophobe renal cell carcinoma
Chromophobe renal cell carcinoma (chRCC) typically shows ~7 chromosome losses (1, 2, 6, 10, 13, 17, and 21) and ~31 exonic somatic mutations, yet carries ~5%-10% metastatic incidence. Since extensive chromosomal losses can generate proteotoxic stress and compromise cellular proliferation, it is intriguing how chRCC, a tumor with extensive chromosome losses and a low number of somatic mutations, can develop lethal metastases. Genomic features distinguishing metastatic from nonmetastatic chRCC are unknown. An integrated approach, including whole-genome sequencing (WGS), targeted ultradeep cancer gene sequencing, and chromosome analyses (FACETS, OncoScan, and FISH), was performed on 79 chRCC patients including 38 metastatic (M-chRCC) cases. We demonstrate that TP53 mutations (58%), PTEN mutations (24%), and imbalanced chromosome duplication (ICD, duplication of ≥ 3 chromosomes) (25%) were enriched in M-chRCC. Reconstruction of the subclonal composition of paired primary-metastatic chRCC tumors supports the role of TP53, PTEN, and ICD in metastatic evolution. Finally, the presence of these 3 genomic features in primary tumors of both The Cancer Genome Atlas kidney chromophobe (KICH) (n = 64) and M-chRCC (n = 35) cohorts was associated with worse survival. In summary, our study provides genomic insights into the metastatic progression of chRCC and identifies TP53 mutations, PTEN mutations, and ICD as high-risk features
Noise effect on Grover algorithm
The decoherence effect on Grover algorithm has been studied numerically
through a noise modelled by a depolarizing channel. Two types of error are
introduced characterizing the qubit time evolution and gate application, so the
noise is directly related to the quantum network construction. The numerical
simulation concludes an exponential damping law for the successive probability
of the maxima as time increases. We have obtained an allowed-error law for the
algorithm: the error threshold for the allowed noise behaves as Eth(N) ~ 1/N1.1
(N being the size of the data set). As the power of N is almost one, we
consider the Grover algorithm as robust to a certain extent against
decoherence. This law also provides an absolute threshold: if the free
evolution error is greater than 0.043, Grover algorithm does not work for any
number of qubits affected by the present error model. The improvement in the
probability of success, in the case of two qubits has been illustrated by using
a fault-tolerant encoding of the initial state by means of the [[7,1,3]]
quantum code.Comment: Accepted to be published in Eur. Phys. J. D (2008
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