Evaluating Synergistic Anti-Cancer Efficacy of Graviola Plant Extracts

癌症仍然是全球最严重的健康风险和死亡原因之一。国际癌症研究机构（IARC）记录了2012年全球超过1400万例新发癌症病例和超过800万例癌症死亡，预测2030年全球超过2100万例新发病例和1300万例新发癌症死亡（Ferlay et al，2015）。世界卫生组织（WHO）和GLOBOCAN均报告2018年全球有960万例癌症相关死亡，与2012年数据相比，死亡率增加了20%（Stewart，2014和Ferlay et al，2018）。高治疗成本、副作用、多病因学和复杂的癌症病理生理学（包括内在和获得性耐药性）对于传统临床干预措施来说越来越成问题（Yuan et al，2015，2017 and 2019）。与植物提取物（PE）相关的协同作用特征已被证明可以有效地利用协同多靶点效应、药代动力学/理化特性以及拮抗耐药性和消除或中和体外和体内不良作用物质的机制来解决上述问题（瓦格纳和Ulrich-Merzenic，2009和南迪等人，2019）。PE的协同效力通常通过广泛使用的Berenbaum等效线法测定，该方法能够定量比较测定相互作用组分相对于PE的各分离单组分总和的药理学和治疗优效性程度（Berenbaum 1997）。在与感染性疾病、肿瘤和免疫炎性疾病相关的常规临床干预方面，常见的方法是在资本密集型模式指导下广泛应用配体特异性单靶点药物。虽然在许多情况下非常成功，但已注意到有效性下降（Petrelli和Giordano，2008和瓦格纳，2010）。多组分联合治疗提供了一种新的替代或补充方法，其中PE特别值得关注，因为某些癌症类型已经显示出对化疗药物的多药耐药性（MDR），占治疗期间癌症死亡的90%（Rather et al 2013：Cercek et al 2020）。来自番荔枝的种子、叶、果肉和树皮提取物，也称为Graviola、guanabana或soursop（除其他名称外），已显示对恶性细胞具有临床显著的抗癌作用，在甚至对化疗药物耐药的癌症中成功诱导细胞死亡/凋亡（Chang et al，2001和Moghadamtousi，et al 2015）。粗Graviola PE（GPE）和部分分级的GPE在体外和体内对乳腺癌、前列腺癌、胰腺癌、皮肤癌和肝癌细胞表现出细胞毒性作用。许多关于GPE中近100种化合物的纯化和表征的报告显示，GPE富含类黄酮、异喹啉、生物碱和番荔枝内酯（Moghadamtousi et al 2015，Sawant and Dongre 2014）。Chan et al 2019，在对Graviola叶提取物（GLE）进行系统性安全性和耐受性审查后，得出了有利的安全性和耐受性特征。番荔枝内酯被认为是GPE中主要通过抑制线粒体复合物1诱导培养细胞细胞毒性的主要植物化学物质组（McLaughlin 2008）。然而，从GPE获得的许多其他化合物尚未在功能上详细说明。值得注意的是，GPE开发为新药实体受到其神经毒性作用和提取/分离过程中某些体内药效作用丧失的限制（Luna Jde等人，2006）。此外，使用单一或几种GPE衍生的乙酸配基导致毒副作用，并最终导致细胞死亡，尽管表现出更大的功效（Sun等人，2014）。然而，这只是燃料的需要，协同研究的GPE，其中黄酮类化合物的存在下，最近已被证明有更大的显着

Cancer remains one of the most serious health risks and cause of death worldwide. The International Agency Research for Cancer (IARC) documented over 14 million new cancer cases and over 8 million cancer deaths worldwide for 2012, forecasting over 21 million new cases and 13 million new cancer deaths worldwide for 2030 (Ferlay et al, 2015). World Health Organisation (WHO) and GLOBOCAN both reported 9.6 million cancer related deaths worldwide for 2018, showing a 20% increase in mortality as compared with 2012 data (Stewart, 2014 and Ferlay et al, 2018). High treatments costs, side-effects, multicausal etiology and the complex pathophysiology of cancer inclusive of an intrinsic and acquired resistance are becoming increasingly problematic for conventional clinical interventions (Yuan et al, 2015, 2017 and 2019). Characteristics of synergy relative to plant extracts (PEs) have been shown to combat the above-mentioned problem effectively utilizing synergistic multi-target effects, pharmacokinetic/physiochemical properties, alongside mechanisms that antagonize resistance and eliminate or neutralize adversely acting substances in vitro and in vivo (Wagner and Ulrich-Merzenic, 2009 and Nandi et al, 2019). The synergistic efficacy of PEs is commonly determined by the widely used Berenbaum's isobole method, able to comparatively determine quantitatively the degree of pharmacological and therapeutic superiority of interacting components relative to the sum of the respective isolate mono constituent of the PEs (Berenbaum 1997). In terms of conventional clinical interventions relative to infectious disease, oncology and immunoinflammatory disease - the common approach is widespread application of ligand specific single target drugs directed by a capital-intensive model. Although highly successful in many cases, a decreasing effectiveness has been noted (Petrelli and Giordano, 2008 and Wagner 2010). Multi component combination therapy provides a novel alternative or complementary approach, where PEs are of particular interest as some cancer types have already shown multi drug resistance (MDR) to chemotherapeutics accounting for 90% of cancer deaths during treatment (Rather et al 2013: Cercek et al 2020). Seed, leaf, fruit-pulp and bark extracts from Annona muricata otherwise known as Graviola, guanabana or soursop (amongst other names) have been shown to possess clinically significant anticancer effects against malignant cells, successful at inducing cell death/apoptosis in cancers resistant to even chemotherapeutic drugs (Chang et al, 2001 and Moghadamtousi, et al 2015). Crude Graviola PEs (GPEs) and partially fractionated GPEs exhibit cytotoxic effects on breast, prostate, pancreas, skin and liver cancer cells in-vitro and in-vivo. Many reports on the purification and characterisation of almost 100 compounds from GPEs are available shown GPEs to be rich in in flavonoids, isoquinoline, alkaloids and annonoaceous acetogenins (Moghadamtousi et al 2015, Sawant and Dongre 2014). Chan et al 2019, after a systematic safety and tolerability review of Graviola leaf extract (GLE) concluded favourable safety and tolerability profile. Annonaceous acetogenins are considered to be the major groups of phytochemicals in GPEs that induce cytotoxicity in cultured cells, mainly via inhibition of mitochondrial complex 1 (McLaughlin 2008). However, many other compounds obtained from GPEs have not been functionally detailed. To note, GPEs development into new drug entities is restricted by its neurotoxic effects and loss in some pharmacotherapeutic effects in vivo effects during extraction/separation processes (Luna Jde et al, 2006). Also use of single or several GPE derived acetogenins lead to toxic side effects and eventually cell death despite expressing greater efficacy (Sun et al, 2014). However, this only fuels the need to synergistic studies on GPEs where flavonoids in presence of acetogenins have recently been shown to have greater significant