Enhanced effectiveness of conventional oncotherapy with plant immunomodulators: Overview of recent advances Tibor Hajtó 1 *, András Adámy 1 , Zoltán Langmár 2 , Angelika Kirsch 3 , Lajos Ábrahám 4 , Pál Perjési 5 and Péter Németh 1 1 Department of Immunology and Biotechnology, Clinical Centre of the University Pecs, Hungary. 2 Semmelweis University, 2nd Department of Gynecology, Budapest, Hungary. 3 Private Praxis, Paradiesstr 14, CH-4102-Binningen, Switzerland. 4 Surgical Departement, Szent János Hospital Budapest, Hungary. 5 Departement of Medical Chemistry, Medical University Pecs, Hungary. Accepted 23 July, 2013 ABSTRACT There is growing evidence that tumor-associated immune imbalance is an important prognostic factor in several types of malignancy. Results from basic research as well as several case reports on sarcoma patients suggest that immune function may be improved by plant immunomodulators. Such treatments hold promise to partially restore the impaired balance along the regulatory access of the innate immune system that may be critical for clinical outcomes. There is also some evidence that combined therapy with plant preparations such as mistletoe extract injections with fixed Viscum album lectin content (0.5 to 1.0 ng/kg twice a week), rice bran preparation with a fixed dose of arabinoxylan (12 to 45 mg/kg twice a week) and wheat germ extract with a fixed dose of 2.6-dimethoxy-p-benzoquinone (50 to 80 mg/kg four times a week) on top of conventional oncotherapy may result in complete remission of hepatic metastases. These results suggest that the combination of these plant immunomodulators with conventional oncologic treatments can render possible complete remissions which are rarely attainable by oncologic therapies only. Studies using SF-36 questionnaires reported improved quality of life in advanced stages of various malignancies with plant-derived lectin immunomodulator. Combined therapy with plant immunomodulators, which are able to bind pattern recognition receptors on effector cells of innate immune system, may improve outcomes compared to conventional oncotherapy. However, further studies are required to provide additional evidence. Keywords: Tumor, immune dysfunction, plant immunomodulator, Viscum album lectin, rice brain preparation, wheat germ extract. *Corresponding author. E-mail: drhajtot@t-online.hu. Tel: 0036-309-735-337. Fax: 0036-268 9999. INTRODUCTION The role of disturbed immune balance in the prognosis of patients with malignant tumors Within the last decade, there has been increased attention focused on the prognostic significance of immune status in malignancy. Specifically, an altered balance in the innate immune system has been identified as an important clinical predictor. Decreased activity of phagocytes and natural killer cells were identified as important features of cancer progression. Several studies were undertaken to characterize this tumor-related immune imbalance identifying important mechanisms. These include disturbed balance between Th1 and Th2 immune responses and increased activity of regulatory T cells and myeloid-derived suppressor cells (Nagtegaal et al., 2001; Ostrand-Rosenberg and Sinka, Advancement in Medicinal Plant Research Vol. 1(3), pp. 56-65, July 2013 Review