1. Field of the Invention
The invention relates to a method for peptide histochemical diagnosis, and in particular, to a method for peptide histochemical diagnosis of the formalin-fixed paraffin-embedded surgical specimens.
2. The Prior Arts
Currently, some targeted peptides for the targeted chemotherapy in cancers have been reported. However, it is difficult to identify whether the peptides can be used to bind to the peptide binding protein in cancer cells by staining the formalin-fixed paraffin-embedded surgical specimens, to confirm the peptides for the targeted chemotherapy in cancers has efficacy in patients before clinical use. Although the patients suffer the same type of cancer, it is still unknown that the peptides for the targeted chemotherapy in different patient cancers can really bind to the individual cancer cells of the patients due to the individual difference. Therefore, to identify whether the peptide can bind to the cancer cells of each patient before chemotherapy, it will be extremely beneficial for the efficacy of peptide-targeted chemotherapy.
Thus, it is the key to evaluate therapy effects of the patient before peptide-targeted chemotherapy, and the main problem is to identify whether the targeted peptide can directly bind to the surgical tumor specimens from the patient. Moreover, the peptides have the following characteristics: a. The peptides can bind to different and undifferentiated nasopharyngeal carcinoma (NPC) or other cancer cells; b. The peptides targeted chemotherapy can make tumor shrink; c. The peptides can not bind to the normal cells in the normal organ tissue. It has been reported that biotin can be directly linked to the peptide to form a biotin-peptide, the biotin-peptide can also bind to cancer cells, but it has poor result in the paraffin-embedded surgical specimens. The biotin-peptide can bind to the small surgical specimens a little, and the binding capability is very weak than that of general antibodies, especially, biotin-peptide almost can not bind to more than 1 cm in diameter of the surgical specimens. The main reason is that the surgical specimens are formalin-fixed paraffin-embedded surgical sections, and there are only three amino acids of the biotin-peptide can bind to the cancer cells embedded in the surgical sections, the binding ability between the peptide and formalin-fixed paraffin-embedded surgical section is very weak, so almost no binding phenomenon can be observed. It is impossible to anticipate the efficacy of chemotherapy for cancer patient after surgery using this method. Currently, there is not yet a method of pathological diagnosis for targeted peptide to bind to formalin-fixed paraffin-embedded specimens in surgical sections.