Combining natural products with chemotherapy and/or radiotherapy may increase the efficacy of cancer treatment. It has been hypothesized that natural products may inhibit DNA repair and sensitize cancer cells to DNA damage-based cancer therapy. However, the molecular mechanisms underlying these activities remain unclear. In this study, we found that diallyl disulfide (DADS), an organosulfur compound, increased the sensitivity of yeast cells to DNA damage and has potential for development as an adjuvant drug for DNA damage-based cancer therapy. We induced HO endonuclease to generate a specific DNA double-strand break (DSB) by adding galactose to yeast and used this system to study how DADS affects DNA repair. In this study, we found that DADS inhibited DNA repair in single-strand annealing (SSA) system and sensitized SSA cells to a single DSB. DADS impaired DNA repair by inhibiting the protein levels of the DNA resection-related proteins Sae2 and Exo1. We also found that the recruitment of MRX and the Mec1-Ddc2 complex to a DSB was prevented by DADS. This result suggests that DADS counteracts G2/M DNA damage checkpoint activation in a Mec1 (ATR)- and Tel1 (ATM)-dependent manner. Only by elucidating the molecular mechanisms by which DADS influences DNA repair will we be able to discover new adjuvant drugs to improve chemotherapy and/or radiotherapy. 相似文献
The Pancoast syndrome (PS) has been termed after Henry Pancoast. Its neurologic core symptoms include pain, radicular sensory and motor syndromes, and Horner syndrome. A PS is often the presenting sign of lung cancer and bears a grim prognosis.
Methods
This case report describes an atypical onset of a lung tumor causing a PS. Electrophysiological examination was not conclusive. The diagnosis was confirmed by MRI, CT scan, and biopsy. The intervention consisted of preoperative chemo- and radiotherapy and was followed by an extensive surgical approach with histologically confirmed perineural invasion of the brachial plexus.
Results
The postoperative period was dominated by neuropathic pain. Despite considerable loss of distal sensorimotor function of the right hand, the patient uses the extremity and has returned to professional life.
Discussion
This observation triggered by the advances in general oncology and surgery also demonstrates the management of a lesion of the peripheral nervous system caused by cancer. 相似文献
Risk of recurrence is a major problem in breast cancer management. Currently available prognostic markers have several disadvantages including low sensitivity and specificity, highlighting the need for new prognostic techniques. One of the candidate techniques is serum‐based Raman spectroscopy (RS). In this study, feasibility of using RS to distinguish ‘pre’ from ‘post’ breast tumor resection serum in rats was explored. Spectral analysis suggests change in proteins and amino acid profiles in ‘post’ compared to ‘pre‐surgical’ group. Principal‐Component‐Linear‐Discriminant‐Analysis shows 87% and 91% classification efficiency for ‘pre’ and ‘post‐surgical’ groups respectively. Thus, the study further supports efficacy of RS for theranostic applications.