Importance of knowledge of tumor biology

Using the words “tumor biology” I did a Google search  on one of my  other websites namely   <docSamBlog>  and found 3 posts. I refer the reader to the one which discusses the importance of formal courses in tumor biology  and nutrition for medical students as well as for practicing doctors- especially oncologists.  We all know that pathogenic bacteria can develop resistance to specific antibiotics . I wonder whether  the poor response in some patients with cancers  to  specific antitumor drugs , and/or the development of remissions are related to the ability of cancer cells to undergo  heteroploid transformation and specific selection of a karyotype. I recall from my research as a cell biologist with the Dept of Cancer Research at the University of Saskatchewan in Saskatoon (1961-1965 period) where I demonstrated that if a single cancer cell  from a cell line was isolated and then allowed to undergo numerous cell divisions in cell culture -I used the tumor cell line called HeLa- that chromosome analysis of many cells from this population showed cells with varying number of chromosomes-ranging from the low 50s to 70’s with a stem cell line in the early 60’s(Hrushovetz, S.B. Importance of heteroploid transformation in the etiology of neoplasia. Proceedings of the 17th Western Regional Group MRC/NCI. 1963).This phenomenon is called heteroploid transformation.For my Master’s degree in Biochemistry from the U. of Alberta  (see publication Phytopathology 47:261-264.1957 )I had earlier shown that the addition of specific amino acids to the culture medium on which the cereal plant pathogen called Helminthosporium sativum was  sub cultivated could alter the virulence of this pathogen in producing root rot disease . Alternatively these experiments could be interpreted  as  demonstrating that for a pathogen to retain its virulence it required the presence in their environment of specific nutrients