Collagen gel droplet-embedded culture drug sensitivity testing in squamous cell carcinoma cell lines derived from human oral cancers: Optimal contact concentrations of cisplatin and fluorouracil

Abstract

Abstract. The collagen gel droplet-embedded culture drug sensitivity test (CD-DST) is an anticancer drug sensitivity test that uses a method of three-dimensional culture of extremely small samples, and it is suited to primary cultures of human cancer cells. It is a useful method for oral squamous cell carcinoma (OSCC), in which the cancer tissues available for testing are limited. However, since the optimal contact concentrations of anticancer drugs have yet to be established in OSCC, CD-DST for detecting drug sensitivities of OSCC is currently performed by applying the optimal contact concentrations for stomach cancer. In the present study, squamous carcinoma cell lines from human oral cancer were used to investigate the optimal contact concentrations of cisplatin (CDDP) and fluorouracil (5-FU) during CD-DST for OSCC. CD-DST was performed in 7 squamous cell carcinoma cell lines derived from human oral cancers (Ca9-22, HSC-3, HSC-4, HO-1-N-1, KON, OSC-19 and SAS) using CDDP (0.15, 0.3, 1.25, 2.5, 5.0 and 10.0 µg/ml) and 0.9, 1.8, 3.8, 7.5,15.0 and 30.0 µg/ml), and the optimal contact concentrations were calculated from the clinical response rate of OSCC to single-drug treatment and the in vitro efficacy rate curve. The optimal concentrations were 0.5 µg/ml for CDDP and 0.7 µg/ml for 5-FU. The antitumor efficacy of CDDP at this optimal contact concentration in CD-DST was compared to the antitumor efficacy in the nude mouse method. The T/C values, which were calculated as the ratio of the colony volume of the treatment group and the colony volume of the control group, at the optimal contact concentration of CDDP and of the nude mouse method were almost in agreement (P<0.05) and predicted clinical efficacy, indicating that the calculated optimal contact concentration is valid. Therefore, chemotherapy for OSCC based on anticancer drug sensitivity tests offers patients a greater freedom of choice and is likely to assume a greater importance in the selection of treatment from the perspectives of function preservation and quality of life, as well as representing a treatment option for unresectable, intractable or recurrent cases.

Clinical study on collagen gel droplet-embedded culture drug sensitivity test for multidrug combination chemotherapy and super selective intra-arterial infusion chemoradiotherapy in oral squamous cell carcinoma

“…On the other hand, the CD-DST that we performed in this study had a potential for a high success rate on initial culture, needed a small number of cells, and used serum-free culture medium and image colorimetry to eliminate the influence of fibroblasts. The CD-DST has the advantage of using an anticancer drug contact concentration that is comparable to the clinical therapeutic dose (5,6,10,25). In fact, the primary measurement success rate of the CD-DST was reported to be 87.5% in colorectal cancer, 79.2% in lung cancer, and 84.3% in breast cancer (11,26,27).…”

Identification of the optimal cetuximab concentration that is effective against oral squamous cell carcinoma in collagen gel droplet embedded culture drug sensitivity testing

“…The CD-DST we performed in the present study has a potentially high success rate, based on initial culture, needs a small number of cells, and uses serum-free culture medium and image colorimetry to eliminate the influence of fibroblasts. The CD-DST has the advantage of using an anticancer drug concentration comparable to the clinical therapeutic dose (5,6,9,10).…”

“…After 1 h, DF medium supplemented with 10% fetal bovine serum was added to each well; the plates were placed in a CO 2 incubator overnight at 37˚C. The following final concentrations of the anticancer drugs were added: 0.5 µg/ml cisplatin (CDDP; Randa Injection 50 mg/100 ml; Nippon Kayaku, Tokyo, Japan) (9); and 0.7 µg/ml fluorouracil (5-FU injection 250 Kyowa ® ; Kyowa Hakko, Tokyo, Japan) (9). The cancer cells were incubated for 24 h. In addition, cetuximab (Erbitux ® Injection 100 mg/20 ml; Merck Serono, Tokyo, Japan) was added at 250 µg/dl and incubated for 144 h as reported by Ryuki et al (10) (Table II).…”

Optimal Cetuximab Contact Concentration Using a Collagen Gel Droplet- Embedded Culture Drug Chemosensitivity Test in Human Oral Squamous Carcinoma Cell Lines

“…The study evaluated six concentrations of cetuximab (10, 50, 250, 500, 750, and 1,000 μg/ml), with the upper limit of 1,000 μg/ ml representing approximately 200% of the mean maximum plasma concentration under clinical dosing and a lower limit of 10 μg/ml, representing approximately 20% of the mean plasma concentration. Cells were contacted to these concentrations in individual wells for 144 h. Single wells were also contacted to CDDP and 5-FU concentrations of 0.5 μg/ml and 0.7 μg/ml for 24 h according to the method described by Sakuma et al [16]. After contact, wells were washed with phosphatebuffered saline (PBS; TAKARA BIO INC., Shiga, Japan) to remove all residual anticancer drugs, and then the cells were cultured in serum-…”