Fig. 1Microsatellite status is determined by size variation and the occurrence of additional bands (arrows) in the polymerase chain reaction product from tumor DNA (B) that are not observed in the analysis of DNA from normal tissue (A) from the same patients.
Fig. 2Overall survival rates according to microsatellite status for all gastric cancers (A) and intestinal-type gastric cancers (B). High-level microsatellite instability (MSI-H) gastric cancer is associated with reduced survival compared to microsatellite stable (MSS)/low-level MSI (MSI-L) gastric cancers in intestinal-type gastric cancers.
Fig. 3High-level microsatellite instability gastric cancer exhibits increased tumor-infiltrating lymphocytes (arrow) (A) and cytoplasmic positivity for MUC6 mucin expression (B).
Table 1.Primary antibodies used in this study
Primary antibody (clone) |
Source |
Dilution |
MUC2 (CLH2) |
Novocastra Laboratories, Newcastle, UK |
1 : 500 |
MUC5AC (CLH5) |
Novocastra Laboratories, Newcastle, UK |
1 : 500 |
MUC6 (Ccp58) |
Novocastra Laboratories, Newcastle, UK |
1 : 500 |
CD10 (56C6) |
Novocastra Laboratories, Newcastle, UK |
1 : 100 |
Table 2.Clinicopathologic characteristics and MSI status in 414 gastric cancers
|
No. of cases |
MSI status
|
p-value |
|
MSS/MSI-L |
MSI-H |
Age (yr) |
|
58.59 ± 11.22 |
64 ± 11.00 |
0.010 |
Gender |
|
|
|
|
Male |
288 |
270 (93.8) |
18 (6.2) |
0.419 |
Female |
126 |
121 (96.0) |
5 (4.0) |
|
Tumor size (cm) |
|
3.77 ± 2.64 |
5.18 ± 3.01 |
0.014 |
Location |
|
|
|
|
Upper/Middle |
195 |
188 (96.4) |
7 (3.6) |
0.140 |
Lower |
219 |
204 (94.4) |
15 (5.6) |
|
Invasion depth (+) |
|
|
|
|
T1 |
225 |
219 (97.3) |
6 (2.7) |
0.009a
|
T2 |
50 |
47 (94.0) |
3 (6.0) |
|
T3 |
86 |
78 (90.7) |
8 (9.3) |
|
T4 |
53 |
48 (90.6) |
5 (9.4) |
|
Gross type |
|
|
|
|
Elevated |
105 |
96 (91.4) |
9 (8.6) |
0.042 |
Flat/Depressed |
180 |
176 (97.8) |
4 (2.2) |
|
Excavated |
129 |
120 (93.0) |
9 (7.0) |
|
Histologic type |
|
|
|
|
Intestinal |
237 |
219 (92.4) |
18 (7.6) |
0.028b
|
Diffuse |
162 |
158 (98.1) |
4 (1.9) |
|
Mixed |
15 |
14 (93.3) |
1 (6.7) |
|
Lymphovascular emboli |
|
|
|
|
Negative |
261 |
252 (96.6) |
9 (3.4) |
0.027 |
Positive |
153 |
140 (91.5) |
13 (8.5) |
|
Perineural invasion |
|
|
|
|
Negative |
280 |
270 (96.4) |
10 (3.6) |
0.022 |
Positive |
134 |
122 (91.0) |
12 (9.0) |
|
Lymph node metastasis |
|
|
|
|
Negative |
246 |
236 (95.9) |
10 (4.1) |
0.170 |
Positive |
168 |
156 (92.9) |
12 (7.1) |
|
Table 3.Multivariate survival analysis with Cox regression model in intestinal type of gastric cancers
Variables |
B |
SE |
HR (95% CI) |
p-value |
Age (≤ 59 yr vs >59 yr) |
-0.213 |
0.335 |
0.808 (0.419-1.588) |
0.525 |
Depth (EGC vs AGC) |
-0.516 |
0.400 |
0.597 (0.273-1.308) |
0.198 |
Site (upper and middle vs lower) |
0.580 |
0.380 |
1.785 (0.847-3.761) |
0.128 |
LN metastasis ([+] vs [-]) |
-1.140 |
0.398 |
0.320 (0.147-0.698) |
0.004 |
MSI (MSI-H vs MSS/MSI-L) |
-0.582 |
0.451 |
0.559 (0.231-1.353) |
0.197 |
Table 4.Relationship between MSI status and histopathologic features in 414 gastric cancers
|
No. of cases |
MSI status
|
p-value |
|
MSS/MSI-L |
MSI-H |
Tumor necrosis (%) |
|
|
|
|
< 10 |
388 |
370 (95.4) |
18 (4.6) |
0.041 |
≥ 10 |
26 |
22 (84.6) |
4 (15.4) |
|
Crohn’s-like reaction |
|
|
|
|
Absent |
208 |
199 (95.7) |
9 (4.3) |
0.368 |
Present |
206 |
193 (93.7) |
13 (6.3) |
|
Extracellular mucin (%) |
|
|
|
|
< 10 |
366 |
345 (94.3) |
21 (5.7) |
0.289 |
≥ 10 |
48 |
47 (97.9) |
1 (2.1) |
|
Tumor infiltrating lymphocytes |
|
|
|
|
< 2/HPF |
337 |
327 (97.0) |
10 (3.0) |
< 0.001 |
≥ 2/HPF |
77 |
65 (84.4) |
12 (15.6) |
|
Growth pattern |
|
|
|
|
Expanding+mixed |
179 |
162 (90.5) |
17 (9.5) |
0.038 |
Infiltrative |
103 |
100 (97.1) |
3 (2.9) |
|
Table 5.Relationship between MSI status and mucin phenotypes and mucin expression in 414 gastric cancers
|
No. of cases |
MSI status
|
p-value |
|
MSS/MSI-L |
MSI-H |
MUC2 (%) |
|
|
|
|
< 10 |
267 |
254 (95.1) |
13 (4.9) |
0.586 |
≥ 10 |
147 |
138 (93.9) |
9 (6.1) |
|
MUC5AC (%) |
|
|
|
|
< 10 |
135 |
131 (97.0) |
4 (3.0) |
0.138 |
≥ 10 |
279 |
261 (93.5) |
18 (6.5) |
|
MUC6 (%) |
|
|
|
|
< 10 |
228 |
221 (96.9) |
7 (3.1) |
0.024 |
≥ 10 |
186 |
170 (91.9) |
16 (8.1) |
|
CD10 (%) |
|
|
|
|
< 10 |
329 |
309 (93.9) |
20 (6.1) |
0.275 |
≥ 10 |
85 |
83 (97.6) |
2 (2.4) |
|
Mucin phenotype |
|
|
|
|
GCGP |
248 |
230 (92.7) |
18 (7.3) |
0.031 |
GCIP+null |
168 |
162 (97.6) |
4 (2.4) |
|
Table 6.Histopathologic features associated with MSI-H gastric cancers
Variables |
B |
SE |
OR (95% CI) |
p-value |
Tumor necrosis ( ≥ 10% vs < 10%) |
1.415 |
0.657 |
4.118 (1.135-14.937) |
0.031 |
TILs ( ≥ 2/HPF vs < 2/HPF) |
1.877 |
0.472 |
6.535 (2.591-16.486) |
<0.001 |
Lauren classification (intestinal+mixed vs diffuse) |
1.597 |
0.647 |
4.938 (1.388-17.566) |
0.014 |
Mucin phenotypes (GC-GP vs GC-IP+null) |
1.356 |
0.583 |
3.881 (1.238-12.170) |
0.020 |
Table 7.Reproted datasets on the microsatellite instability and survival in gastric cancer
Authors (yr) |
n |
Markers |
Methods |
MSI-H (%) |
Survival |
Present study |
414 |
BAT25, BAT26, D5S346, D2S123, D17S250 |
Fluorescence |
5.6 |
MSI-H have poor survival in intestinal type gastric cancer |
An et al. [25] (2012) |
1,990 |
BAT25, BAT26, D5S346, D2S123, D17S250 |
Fluorescence |
8.5 |
No correlation |
Oki et al. [24] (2009) |
240 |
D2S123, D5S107, D10S197, D11S904, D13S175 |
Fluorescence |
9.4 |
No correlation |
Seo et al. [12] (2009) |
328 |
BAT25, BAT26, D5S346, D2S123, D17S250 |
Fluorescence |
8.2 |
No correlation |
Falchetti et al. [6] (2008) |
159 |
BAT25, BAT26, D1S104, D2S123,D3S1611, D5S107, D17S261, D18S342 |
Fluorescence |
17.0 |
MSI-H have good survival in gastric cancer |
Beghelli et al. [7] (2006) |
510 |
BAT25, BAT26 |
Fluorescence |
16 |
MSI-H have good survival in gastric cancer |
An et al. [13] (2006) |
83 |
BAT25, BAT26, D5S346, D2S123, D17S250 |
Fluorescence |
19 |
No correlation |
Lee et al. [5] (2002) |
327 |
BAT25, BAT26 |
Fluorescence |
9.5 |
MSI-H have good survival in advanced gastric cancer |
Yamamoto et al. [4] (1999) |
205 |
BAT25, AP△3, D1S158, D8S199, D5S421 |
Radiolabelled |
14 |
MSI-H have good survival in advanced gastric cancer |
Wirtz et al. [14] (1998) |
126 |
BAT25, BAT26, D2S119, D2S123, D5S107, D5S346, D10S197, D11S904, D17S261, D18S34 |
Radiolabelled |
12.8 |
No correlation |