針對熱休克蛋白與熱傷害表現最適化雷射治療設計

Abstract

雷射熱治療是一種藉由雷射產生高溫來破壞腫瘤細胞的癌症治療方式，但其治療效果卻會因為熱休克蛋白(heat shock protein，簡稱HSP)的形成而受到影響。HSP為生物體受熱時，由體內細胞所合成的一種保護性蛋白質，具有幫助生物體恢復已變性之蛋白質以及增加細胞之耐熱性等功能。一般來說，健康細胞與腫瘤細胞在受熱後皆會產生HSP，因此，若能透過適當的模型來探討生物體內之HSP表現情況，將有助於雷射熱治療在臨床上的應用。 本研究分別以單點雷射與多點雷射的方式進行三個不同樣本之模擬。經由最適化的過程找出符合該樣本之最佳治療模式，不僅有效抑制腫瘤細胞之HSP表現使其受到預期的熱傷害，而且盡可能地促進健康細胞之HSP表現以減低其損傷。樣本一為外部雷射治療規則形狀之腫瘤，樣本二為內部雷射治療規則形狀之腫瘤，樣本三則為外部雷射治療不規則形狀之腫瘤。三個樣本的治療結果均顯示出腫瘤細胞已確實破壞，然而健康細胞所受到的熱傷害與其HSP表現則會因為不同的雷射操作方式而有所差異。在大部分的情況下，多點雷射的治療效果要比單點雷射來得好，尤其是對於不規則形狀之腫瘤時，使用多點雷射的方式較容易掌握溫度分佈進而控制熱傷害程度以及細胞之HSP表現。

Hyperthermia therapy is a type of cancer treatment on the use of laser to generate high temperature to damage and kill the tumor cells. Nevertheless, the curative effect of such therapy is influenced by the formation of heat shock proteins (HSP). HSP are a group of protective proteins produced by cells while the body is exposed to elevated temperatures, which have the functions to restore the denatured proteins and enhance the heat resistance of cells. Generally speaking, both healthy cells and tumor cells will synthesis HSP under heat, and therefore it is contributive to the clinical application of hyperthermia therapy to investigate and analyze the expression of HSP in body tissues by an adequate model. This work presents the simulations for three different examples by means of single laser and multi-laser, respectively. Through the procedure of optimization, the optimal treatments for corresponding examples are found, which not only restrain the expression of HSP in tumor cells to cause them the anticipant thermal damage, but also encourage the expression of HSP in healthy cells to mitigate their injury. The first two examples are about the external and internal laser treatments for a regular-shaped tumor, whereas the third example involves the external laser treatment for an irregular -shaped tumor. Results of those three examples have all shown that the tumor cells are effectively damaged while the thermal damage to healthy cells is varied with different operating modes of laser treatment. In the main, the curative effect of multi-laser is better than that of single laser, especially for the irregular-shaped tumors. It is because the use of multi-laser is easier to govern the temperature distribution as well as the damage degree and the expression of HSP in body cells.