Table 2.
Mismatch repair dysfunction in sporadic gastrointestinal tract cancer
|
(a) Frequencies of MSI observed in gastric, stomach, and colorectal cancer | |||
|---|---|---|---|
| MSI † | Reference no. | Frequencies cited in the literature ‡ | |
| (i) Esophagus | 8% | ( 26 ) | 5–25% |
| (MSI‐L 8%) | |||
| (MSI‐H 0%) | |||
| (ii) Stomach | 24% | ( 24 ) | 13–44% |
| (MSI‐L 13%) | |||
| (MSI‐H 11%) | |||
| (iii) Colon | 34.7% | ( 25 ) | 15–50% |
| (MSI‐L 23.1%) | |||
| (MSI‐H 11.6%) | |||
|
(b) Involvement of MMR genes in esophageal, gastric, and colorectal cancer | |||
|---|---|---|---|
| MMR gene | Proportion | Method used for analysis | Reference no. of alteration |
| (i) Esophagus | |||
| MSH2, MLH1, MSH6 | 14% | In vitro MMR assay′ | ( 31 ) |
| MSH3, PMS2 | |||
| MLH1 | 33% | MSP | ( 32 ) |
| MSH2, MLH1 | 28.7% | IHC | ( 33 ) |
| (ii) Stomach | |||
| MLH1 | 31% | MSP, IHC, RT‐PCR | ( 36 ) |
| MLH1 | 32% | MSP, IHC, WB | ( 37 ) |
| MSH2, MLH1 | 0% | IHC | ( 40 ) |
| MSH2, MLH1 | 32–36% | IHC | ( 39 ) |
| (iii) Colon | |||
| MSH2, MLH1 | 7% | Mutation or LOH | ( 43 ) |
| (among MSI) | |||
| MLH1 | 25–64% | IHC (64%), MSP (42%) | ( 46 ) |
| (among MSI‐H,MSS) | Mutation (26%) | ||
| MSH2 (among MSI) | <1% | Mutation | ( 44 ) |
| MSH2, MLH1 | 12% | IHC | ( 45 ) |
| MSH6 (among MSI‐L) | 7–17% | IHC (17%) | ( 47 ) |
| Mutation (7%) | |||
| MSH2, MLH1, MSH6 | 0–12% | IHC | ( 48 ) |
| PMS2 | |||
†
MSI is analyzed using fluorescent primers and an auto sequencer.( 13 )
‡
Frequencies of MSI are reviewed in the article.( 24 ) MSI, microsatellite instability.
IHC, immunohistochemistry; LOH, loss of heterozygosity; MMR, mismatch repair; MSI, microsatellite instability; MSP, methylation‐specific PCR; RT‐PCR, reverse transcription‐polymerase chain reaction; WB, western blotting.