The negative charge derived from acidic glycosaminoglycans (AGAG), the important component in the ground substance of the connective tissue, seems to correlate with a reduction in the adhesiveness of the tumor cells and the appearance of early metastases. In addition, the transformation of normal to malignant cells seems to be accompanied by an increase in the negative electrical charge carried by the structural components of the cell membranes, one of which is sialic acids (SA). Therefore, both AGAG and SA extracted from the tissue of head and neck cancer were analyzed and were compared to those in chronic maxillary sinusitis and in normal tissues.AGAG were qualitatively and quantitatively analyzed by electrophoretic separation and densitometric quantitation, while SA were done by thiobarbituric acid assay and spectrophotometric qualitation and quantitation.The results for AGAG were as follows:1) Hyaluronic acid, dermatan sulfate (DS) and chondroitin sulfate A were the main components of AGAG in maxillary cancer. However, small amounts of heparan sulfate and chondroitin sulfate C were also detected. The components detected in chronic maxillary sinusitis were the same, although there were some differences in contents.2) In the tissue of maxillary cancer, the total amount of AGAG increased slightly. However, there were quantitative differences in AGAG, depending on the grade of differentiation; in the case of moderately differentiated squamous cell carcinoma, they were prominently increased.3) The characteristic differences in AGAG between such squamous cell carcinoma as maxillary and laryngeal cancers and such adenocarcinoma as thyroidal cancer was that the amount of DS was smaller in the former and larger in the latter compared to that of normal tissues.4) X-rays and Bleomycin were presumed to activate the stroma, while BUdR and 5-FU were presumed to suppress the stroma.5) When bio-reaction to tumor was biochemically investigated, DS was found to be closely involved, and a large amount of DS in the tissue surrounding the tumor seemed to be keeping the tumor confined via fibrosis. Therefore, the increase or deccrease of DS in the tissue surrounding the tumor seemed to be a possible parameter for the host-tumor relationship.The results for SA were as follows:1) Contrary to the expectation derived from previous reports, the total amount of SA in the tissue of maxillary cancer per dry weight did not show any conspicuous change compared to that in the normal maxillary sinus mucosa.2) In the case of malignant tumor, a higher histological malignancy was associated with a lower SA/DNA; and metabolic disorder of SA at the malignant cell membrane was strongly suggested.3) The edematous type of chronic maxillary sinusitis contained significantly larger amounts of SA/DNA than normal. This suggested that the edematous type of chronic sinusitis was an early stage of chronic inflammation.Analysis and comparison of AGAG and SA with regard to maxillary cancer and mucosae in chronic maxillary sinusitis suggested a possible correlation between chronic supprative maxillary sinusitis and maxillary cancer.