Informatics Publishing Limited

P. Kanagaraj ¹, M. R. Vijayababu ¹, B. Ravisankar ¹, J. Anbalagan ¹, M. M. Aruldhas ¹, J. Arunakaran ¹

Affiliations
1 Department of Endocrinology, Dr ALM Post-Graduate Institute of Basic Medical Sciences, University of Madras, Taramani, Chennai - 600 113, IN

Abstract

Prostate cancer is the second most common cancer that leads to death in elderly men. The risk of prostate cancer prevalence is often associated with elevated level of insulin-like growth factor I (IGF-I) and decreased level of IGF-binding protein 3 (IGFBP-3). Lycopene, a carotenoid, reduces the proliferation of cancer cells and, thus, induces apoptosis. Hence, higher intake of lycopene can be associated with a lower risk of prostate cancer. However, the mechanism of action of lycopene in prostate cancer is still unclear. The present study was carried out to find the effects of lycopene on the components of IGF system and apoptosis in an androgen-independent prostate cancer cell (PC-3). PC-3 cells were treated with various concentrations of lycopene, 20, 40 and 60 μM, each for 24, 48, 72 and 96 h, IGF-1, IGFBP-3 and IGF-I receptor (IGF-IR) levels and indication of apoptosis were evaluated. The proliferation of lycopene-treated PC-3 cells decreased significantly. At a concentration of 40 μM lycopene treatment significantly increased the level of IGFBP-3. Lycopene-induced apoptosis was indicated in annexin V and PI binding. Lycopene-induced DNA fragmentation was not detectable after 24 h after the treatment whereas the same was observed after 48 h treatment. There was a significant decrease in the IGF-IR expression after the cells were treated with lycopene and IGF-I. The data obtained suggest that the components of the IGF system may act as a positive regulator for lycopene-induced apoptosis in PC-3 cells. The results obtained are encouraging and may lead to the development of lycopene as a potential therapy for prostate cancer.

Keywords

Lycopene, IGFBP-3, IGF-I, IGF-IR, Prostate Cancer.

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Chittaranjan Das ¹, Arun Kumar Bhaduri ², V. Thomas Paul ², S. K. Albert ², M. Vijayalakshmi ², Krishnam Raju ³, B. Ravisankar ⁴

Affiliations
1 Indira Gandhi Centre for Atomic Research, Kalpakkam 60310, IN
2 Indira Gandhi Centre for Atomic Research, IN
3 National Institute of Technology, Tiruchirapalli 62001, IN
4 Indira Gandhi Centre for Atomic Research, Kalpakkam 603102, IN

Abstract

Modified 9Cr-1Mo steel is extensively used for high temperature applications due to its good thermo-physical, weldability, fabricability and high temperature properties. While Type IV cracking is of concern during service of weld joints, toughness of its weldmetal is an important consideration during qualification of weld joints, especially for those made by SMAW process. The weldmetal toughness is significantly influenced by deposition process and sequence, and temperature and duration of PWHT. For a special-purpose mod.9Cr-1Mo steel weldmetal, containing intentional addition of 2.4wt% of nickel and manganese, the A and A transformation temperatures, calculated using ThermoCalc software, was found as 945 and 1065K, respectively. To understand its tempering behavior, the weldmetal was subjected to PWHT at 1013, 1033 and 1053K for different durations. The weldmetal hardness decreased significantly on PWHT at 1013K compared to that at 1033 and 1053K. The weldmetal toughness increased monotonically with PWHT temperature; from 27J for 923K PWHT to 32J and 132J for 973K and 1023K PWHTs, respectively, and then decreased marginally to 113J on PWHT at 1153K. These results suggested formation of fresh martensite during PWHT at 1053K. Bright-field transmission electron microscopic examination revealed formation of lath martensite in the weldmetal, with the lath sizes being finer than those reported in other mod. 9Cr-1Mo steel weldmetal prepared using similar process. Hence, detailed microstructural analyses was carried out to investigate this anomalous variation in mechanical properties, as also to study the effect of temperature and duration of PWHT on the microstructure and toughness of this modified 9Cr-1Mo steel weldmetal.

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