Autochthonous tumors

Key words Metastasis, autochthonous tumors, genetically engineered tumor models, orthotopic... 

One of the most important questions concerning the antitumor effect of these polysaccharides is whether they can inhibit the growth of autochthonous tumors. Transplanted tumors, be they syngeneic or allogeneic, are artifacts produced in the laboratory, and are not necessarily truly comparable with tumors that arise spontaneously within the body of the host (autochthonous tumors). 

Despite the fact that all of the so-called antitumor polysaccharides hitherto discovered proved totally without effect on autochthonous, animal tumors, some relationships may exist between the mechanism of allogeneic, transplanted-tumor rejection and the suppression of autochthonous tumors, as indicated by experiments of Tokuzen and Nakahara.253,254... 

The polysaccharides so far examined, although strongly active in suppressing transplanted tumors, do not seem eligible for clinical trial in human cancer therapy. Therefore, to search for new polysaccharides more strongly antitumor-active than those thus far discovered, and, especially, ones that may have an inhibiting action on autochthonous tumors, stands as a challenge for further studies on antitumor polysaccharides. 

Lentinan exerts prominent antitumor effects on various syngeneic and autochthonous tumors induced by 3-methylcholanthrene as well as on allogeneic tumors, as shown in Table 3 [5-8]. Carcinogenesis induced by 3-methylcholanthrene in SWM/Ms and DBA/2 mice is also suppressed by lentinan from 83% to 33%, and... 

As mentioned, Tokuzen223 examined local, cellular reactions around Sarcoma 180 grafts during the process of regression under polysaccharide treatment, and found a massive outpouring of lymphoid cells one week after tumor implantation. Autochthonous grafts of spontaneous, mammary tumors, not at all inhibited by polysaccharides, called forth no local, lymphoid-cell infiltration.252... 

Pollard M, Luckert PH, Schmidt MA. The suppressive effect of piroxicam on autochthonous intestinal tumors in the rat. Cancer Lett. 21 (1983) 57-61. 

Mitomycin C - Human sarcoma cells exposed to mitomycin C stimulated DNA synthesis in autochthonous lymphocytes. Preexposure of the tumor cells to autochthonous serum abrogated lymphocyte stimulation. 22 The use of mitomycin C in combination with cycle-phase specific drugs that may block cell repair, or with agents having a different mode of action has been suggested, 23 but preliminary combinations with phenylalanine mustardj and vincristine in the treatment of osteogenic sarcoma was without much... 

Andersson, U., Leighton, B., Young, M.E., et al., 1998. Inactivation of aconitase and oxoglutarate dehydrogenase in skeletal muscle in vitro by superoxide anions and/or nitric oxide. Biochem. Biophys. Res. Commun. 249, 512-516. Anikin, I.V., Goncharov, N.V., Tyndyk, M.L., et al., 2013. Effect of sodium fluoroacetate on growth of Ehrlich solid tumor and autochthonous mouse sarcoma. Vopr. Oncol. 59 (6), 777-780. Article in Russian. 

Autochthonous lymphocytes activated vitro with phytohemaglutinin (PHA) and applied to subcutaneous metastatic nodules resulted in a greater percent regression than non-activated lymphocytes but the degree of regression in those nodules which were affected was not significantly different from the control group.This study reemphasized the need for effector lymphocytes at the site of the tumor. 

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