Ionizing radiation is one of the most effective tools in cancer therapy. In a previous study, we reported that protein tyrosine kinase (PTK) inhibitors modulate the radiation responses in the human chronic myelogenous...Ionizing radiation is one of the most effective tools in cancer therapy. In a previous study, we reported that protein tyrosine kinase (PTK) inhibitors modulate the radiation responses in the human chronic myelogenous leukemia (CML)cell line K562. The receptor tyrosine kinase inhibitor, genistein, delayed radiation-induced cell death, while non-recepter tyrosine kinase inhibitor, herbimycin A (HMA) enhances radiation-induced apoptosis. In this study, we focused on the modulation of radiation-induced cell death by genistein and performed PCR-select suppression subtractive hybridization(SSH) to understand its molecular mechanism. We identified human thymidine kinase 1 (TK1), which is cell cycle regulatory gene and confirmed expression of TK1 mRNA by Northern blot analysis. Expression of TK1 mRNA and TK 1enzymatic activity were parallel in their increase and decrease. TK1 is involved in G1-S phase transition of cell cycle progression. In cell cycle analysis, we showed that radiation induced G2 arrest in K562 cells but it was not able to sustain. However, the addition of genistein to irradiated cells sustained a prolonged G2 arrest up to 120 h. In addition,the expression of cell cycle-related proteins, cyclin A and cyclin B 1, provided the evidences of G1/S progression and G2-arrest, and their relationship with TK1 in cells treated with radiation and genistein. These results suggest that the activation of TK1 may be critical to modulate the radiation-induced cell death and cell cycle progression in irradiated K562 cells.展开更多
BACKGROUND One of the causes of foot drop is compression of the common peroneal nerve caused by space-occupying lesions such as a synovial cyst or a ganglion cyst.Most previous reports have involved compressive common...BACKGROUND One of the causes of foot drop is compression of the common peroneal nerve caused by space-occupying lesions such as a synovial cyst or a ganglion cyst.Most previous reports have involved compressive common peroneal neuropathy by intraneural ganglion cysts and synovial cysts.Compression of the peroneal nerve by extraneural ganglion cysts is rare.We report a rare case of compressive common peroneal neuropathy by an extraneural ganglion cyst.CASE SUMMARY A 46-year-old man was hospitalized after he reported a right foot drop for 1 mo.Manual muscle testing revealed scores of 1/5 on dorsiflexion of the right ankle.Hypoesthesia and paresthesia on the right lateral leg and foot dorsum were noted.He was diagnosed with a popliteal cyst by using electrophysiologic study and popliteal ultrasound(US).To facilitate common peroneal nerve(CPN)decompression,2 cc of sticky gelatinous material was aspirated from the cyst under US guidance.Electrical stimulation and passive and assisted active ROM exercises of the right ankle and strengthening exercises for weak muscles using elastic band were prescribed based on the change of muscle power.A posterior leaf spring ankle-foot orthosis was prescribed to assist the weak dorsiflexion of the ankle.Follow-up US revealed that the cystic lesion was growing and magnetic resonance imaging demonstrated compression of the CPN by the cystic mass.The cyst was resected to prevent impending compression of the CPN.CONCLUSION Precise diagnosis and immediate treatment are important in cases of compressive common peroneal neuropathy caused by an extraneural cyst.展开更多
文摘Ionizing radiation is one of the most effective tools in cancer therapy. In a previous study, we reported that protein tyrosine kinase (PTK) inhibitors modulate the radiation responses in the human chronic myelogenous leukemia (CML)cell line K562. The receptor tyrosine kinase inhibitor, genistein, delayed radiation-induced cell death, while non-recepter tyrosine kinase inhibitor, herbimycin A (HMA) enhances radiation-induced apoptosis. In this study, we focused on the modulation of radiation-induced cell death by genistein and performed PCR-select suppression subtractive hybridization(SSH) to understand its molecular mechanism. We identified human thymidine kinase 1 (TK1), which is cell cycle regulatory gene and confirmed expression of TK1 mRNA by Northern blot analysis. Expression of TK1 mRNA and TK 1enzymatic activity were parallel in their increase and decrease. TK1 is involved in G1-S phase transition of cell cycle progression. In cell cycle analysis, we showed that radiation induced G2 arrest in K562 cells but it was not able to sustain. However, the addition of genistein to irradiated cells sustained a prolonged G2 arrest up to 120 h. In addition,the expression of cell cycle-related proteins, cyclin A and cyclin B 1, provided the evidences of G1/S progression and G2-arrest, and their relationship with TK1 in cells treated with radiation and genistein. These results suggest that the activation of TK1 may be critical to modulate the radiation-induced cell death and cell cycle progression in irradiated K562 cells.
文摘BACKGROUND One of the causes of foot drop is compression of the common peroneal nerve caused by space-occupying lesions such as a synovial cyst or a ganglion cyst.Most previous reports have involved compressive common peroneal neuropathy by intraneural ganglion cysts and synovial cysts.Compression of the peroneal nerve by extraneural ganglion cysts is rare.We report a rare case of compressive common peroneal neuropathy by an extraneural ganglion cyst.CASE SUMMARY A 46-year-old man was hospitalized after he reported a right foot drop for 1 mo.Manual muscle testing revealed scores of 1/5 on dorsiflexion of the right ankle.Hypoesthesia and paresthesia on the right lateral leg and foot dorsum were noted.He was diagnosed with a popliteal cyst by using electrophysiologic study and popliteal ultrasound(US).To facilitate common peroneal nerve(CPN)decompression,2 cc of sticky gelatinous material was aspirated from the cyst under US guidance.Electrical stimulation and passive and assisted active ROM exercises of the right ankle and strengthening exercises for weak muscles using elastic band were prescribed based on the change of muscle power.A posterior leaf spring ankle-foot orthosis was prescribed to assist the weak dorsiflexion of the ankle.Follow-up US revealed that the cystic lesion was growing and magnetic resonance imaging demonstrated compression of the CPN by the cystic mass.The cyst was resected to prevent impending compression of the CPN.CONCLUSION Precise diagnosis and immediate treatment are important in cases of compressive common peroneal neuropathy caused by an extraneural cyst.
