中文版谷歌中文翻譯（90% 準確率) | English translation
Buy/Sell Your Domains Here。在這裡購買/出售您的域名
Contact Dr. Lu for information about cancer treatments。聯繫盧博士，獲取有關癌症治療資訊。
Press-pulse: a novel therapeutic strategy for the metabolic management of cancer 癌症代謝管理的新治療策略
Contact Dr. Lu for information about cancer treatments。聯繫盧博士，獲取有關癌症治療資訊。
Background
According to the paleobiologists, Arens and West, the simultaneous occurrence of “Press-Pulse” disturbances was considered the mechanism responsible for the extinction of organic populations during prior evolutionary epochs [1]. A “press” disturbance was considered a chronic environmental stress on all organisms in an ecological community. The press disturbance promoted extinction through habitat loss, reduced reproduction, and restriction of range and resources. Press disturbances would force a biological community into a new equilibrium where previously important species become non-viable. A press disturbance would shift the adaptive landscape to favor the fittest species while eliminating the weakest species. In contrast to the press disturbances, “pulse” disturbances were considered acute events that disrupted biological communities to produce high mortality [1]. Through extensive mortality in the immediate aftermath of the event, a pulse disturbance could cause extinction. However, survival of some species could occur following a pulse disturbance, as the physical and biotic environments would eventually recover to their pre-disturbance equilibria [1]. It was only when both the press and the pulse disturbances coincided that mass extinction of species, without recovery, was possible. We describe how a modification of the press-pulse concept can be adopted as a therapeutic strategy for the possible eradication of tumor cells. The press-pulse concept should be best considered in light of current views on the origin of cancer.
The origin of cancer
Cancer is a systemic disease involving multiple time- and space-dependent changes in the health status of cells and tissues that ultimately lead to malignant tumors [2]. Neoplasia involving dysregulated cell growth is the biological endpoint of the disease [3, 4]. Tumor cell invasion into surrounding tissues and their spread (metastasis) to distant organs is the primary cause of morbidity and mortality of most cancer patients [5, 6, 7, 8, 9]. Data from the American Cancer Society show that the rate of increase in cancer deaths/year (3.4%) was two-fold greater than the rate of increase in new cases/year (1.7%) from 2013 to 2017 [10, 11]. Indeed, cancer is predicted to overtake heart disease as the leading cause of death in Western societies. The failure to clearly define the origin of cancer is responsible in large part for the failure to significantly reduce the cancer death rate from treatments and in developing cancer prevention strategies [12].
Cancer is generally considered a genetic disease where random somatic mutations underlie the origin and progression of the disease [4, 13, 14, 15, 16]. This general view is now under serious reconsideration in light of major inconsistencies with the gene theory [2, 3, 12, 14, 17, 18, 19, 20, 21,22, 23, 24]. Emerging evidence from the cancer genome projects shows that most malignant tumors are remarkably heterogeneous [2, 15, 16, 25, 26, 27]. This degree of heterogeneity will confound attempts to exploit genomic defects for effective therapies. Moreover, the majority of genetic mutations are considered downstream epiphenomena of dysregulated energy metabolism [2, 20,28]. In contrast to the extensive genetic heterogeneity seen in tumors, most if not all neoplastic cells within tumors share the common metabolic malady of aerobic fermentation that arises ultimately from dysregulated oxidative phosphorylation [2, 17, 29, 30, 31, 32, 33]. In light of these findings, cancer can also be recognized as a metabolic disease.
Methods
Aerobic fermentation: a common metabolic malady of tumor cells
Most cells of the body oxidize glucose to CO2 and water for energy production. Before entering the mitochondria for complete oxidation, glucose is first split into two molecules of pyruvate through the Embden–Meyerhof–Parnas glycolytic pathway in the cytosol. As most cells are bathed in oxygen, the production of pyruvate occurs through aerobic glycolysis [34]. Under hypoxia, however, much of the pyruvate is reduced to lactic acid in order to maintain cell ATP production. Aerobic fermentation, on the other hand, involves the production of lactic acid under normoxic conditions. As the Pasteur effect should reduce lactic acid fermentation under normoxia, persistent lactic acid production in the presence of adequate oxygen is indicative of abnormal respiration [35]. Otto Warburg first proposed that all cancers arise from damage to cellular respiration. As a result, cancer cells increase their capacity to produce lactic acid even in the presence of oxygen in order to compensate for their insufficient respiration [31, 36].
Although Warburg’s hypothesis on the origin of cancer has created confusion and controversy [37,38, 39, 40], his hypothesis has never been disproved. The Crabtree effect and the high oxygen consumption rate seen in some tumor cells have confused the picture of defective oxidative phosphorylation in tumor cells. The Crabtree effect is an artifact of the in vitro environment and involves the glucose-induced suppression of respiration with a corresponding elevation of lactic acid production even under hyperoxic (pO2 = 120–160 mmHg) conditions associated with cell culture, [41,42]. Also, the oxygen consumption seen in tumor cells is not always linked to ATP production through oxidative phosphorylation and cannot therefore be used alone as evidence of normal respiration [29, 43, 44, 45, 46, 47, 48]. It can be difficult to accurately measure mitochondrial respiratory function in cultured cells unless appropriate controls are used, as the in vitro environment can alter mitochondrial function [41, 49]. These issues have confounded the interpretation of Warburg’s findings despite his attempts to clarify the issues [32, 48, 50]. Nevertheless, the Warburg theory of insufficient aerobic respiration remains as the most credible explanation for the origin of tumor cells [2, 37, 51, 52, 53, 54, 55, 56, 57].
刘 大卫
Trust God, not sinful people. Worship God, but not things/people. Let God lead you, but not let others lead you. 相信上帝，而不是有罪的人。 敬拜神，而不是事/人。 讓上帝帶領你，但不要讓別人帶領你。
