Protein Phosphatase 1 Regulatory Subunit 3: A Prognostic Biomarker in Stomach Adenocarcinoma

Figures & data

Figure 1 PPP1R3B was overexpressed in STAD tissues.

Notes: PPP1R3B mRNA expression levels in different cancer samples were explored using the Oncomine (A) and UALCAN databases (B). *P<0.05, **P <0.01, ***P < 0.001.

Figure 2 PPP1R3B expression in STAD tissues. (A–F) Expression of PPP1R3B in STAD in terms of clinical variables. (G-I) Images of immunohistochemical staining showing PPP1R3B protein expression in STAD from The Human Protein Atlas. ***P < 0.001.

Table 1 Correlation Between OS and Clinicopathologic Features of GC Patients

Variables	Events/Total (n=351)	MST (Months)	HR (95% CI)	Log-Rank P-value
PPP1R3B	144/351	29		<0.001
Low	57/175	60	1
High	87/176	22	2.012(1.431–2.828)
Age (years)	144/348	29		0.022
<60	36/108	60	1
≥60	108/240	26	1.549(1.061–2.263)
Missing	3
Gender	144/351	29		0.178
Male	100/226	29	1
Female	44/125	35	0.784(0.551–1.118)
Missing	0
Tumor location	138/337	29		0.919
Cardia	36/84	26	1
Body	50/123	28	0.916(0.596–1.407)
Antrum	52/130	35	0.936(0.611–1.432)
Missing	14
HP infection	66/161	43		0.304
Positive	6/18	58	1
Negative	60/143	43	1.552(0.667–3.614)
Missing	190
Histologic type	144/350	29		0.057
Intestinal	64/160	38	1
Diffuse	24/61	60	1.001(0.625–1.603)
Signet ring cell	8/11	13	2.515(1.204–5.251)
Others	48/118	26	1.287(0.884–1.875)
Missing	1
Histologic grade	140/342	29		0.169
G1	2/9	NA	1
G2	48/127	43	1.666(0.405–6.862)
G3	90/206	26	2.217(0.546–9.008)
Missing	9
MSI status	144/350	29		0.225
MSI-H	99/240	28	1
MSI-L	22/51	29	1.263(0.794–2.007)
MMS	23/59	35	0.756(0.481–1.191)
Missing	1
Pathological M	138/336	29		0.012
M1	13/23	12	1
M0	125/313	35	0.486(0.274–0.861)
Missing	15
Pathological N	139/341	29		0.004
N0	28/103	60	1
N+	111/238	25	1.826(1.206–2.764)
Missing	10
Pathological T	140/347	31		0.009
T1/T2	28/91	70	1
T3/T4	112/256	26	1.730(1.138–2.269)
Missing	4
TNM stage	136/338	29		<0.001
Stage I	11/47	73	1
Stage II	34/109	56	1.608(0.813–3.182)
Stage III	69/147	26	2.435(1.286–4.610)
Stage IV	22/35	16	3.789(1.836–7.819)
Missing	13
Cancer status	121/324	37		<0.001
No	35/206	NA	1
Yes	86/118	17	5.526(3.695–8.264)
Missing	27
Radiation therapy	135/328	31		0.001
Yes	19/62	NA	1
No	116/266	26	2.322(1.418–3.802)
Missing	23
Targeted therapy	134/326	31		0.022
Yes	56/151	43	1
No	78/175	26	1.489(1.055–2.100)
Missing	25

Abbreviations: PPP1R3B, protein phosphatase 1 regulatory subunit 3B; HR, hazard ratio; MST, median survival time; OS, overall survival; GC, gastric cancer; G1, highly differentiated; G2, moderately differentiated; G3, poorly differentiated; MSI-H, microsatellite instability-altitude; MSI-L, Microsatellite instability-altitude.

Table 2 Multivariate Analyses of the PPP1R3B in the Prediction of Gastric Cancer Overall Survival

Variables	HR (95% CI)	P-value
PPP1R3B (high vs low)	1.792(1.193–2.692)	0.005
Age (years) (≥60 vs <60)	1.574 (1.023–2.422)	0.039
Pathological M (M0 vs M1)	1.168 (0.418–3.266)	0.767
Pathological T (T3/4 vs T1/2)	1.454 (0.743–2.847)	0.275
Pathological N (N+ vs N0)	1.889 (0.885–4.031)	0.100
TNM stage
Stage II vs Stage I	1.400 (0.453–4.328)	0.559
Stage III vs Stage I	1.142 (0.286–4.568)	0.851
Stage IV vs Stage I	1.574 (0.359–6.903)	0.548
Radiation therapy (No vs Yes)	1.215 (0.637–2.319)	0.554
Targeted molecular therapy (No vs Yes)	1.667 (1.049–2.648)	0.030
Cancer status (Yes vs No)	5.319 (3.320–8.523)	<0.001

Abbreviations: PPP1R3B, protein phosphatase 1 regulatory subunit 3B; HR, hazard ratio; CI, confidence interval; T, tumor; N, node; M, metastasis.

Figure 3 Prognostic model of PPP1R3B in patients with STAD.

Notes: (A) From up to down are risk score plot, survival status scatter plot, and heat map of the expression of PPP1R3B for low‐and high‐risk groups. (B) Kaplan–Meier survival curves for PPP1R3B gene in STAD of TCGA cohort. (C) Receiver operating characteristic curve for predicting overall survival in STAD patients by the PPP1R3B.

Table 3 Stratified Analysis of PPP1R3B Gene and OS in GC Patients

Group	Low		High	Crude HR (95% CI)	Crude P-value	Adjusted HR (95% CI)	Adjusted P-value^a
Age(years)
<60	55	53		2.701(1.335–5.465)	0.006	5.000(2.012–12.425)	0.001
≥60	118	122		1.711(1.161–2.521)	0.007	2.029(1.324–3.109)	0.001
Pathological T
T 1/2	40	51		3.012(1.224–7.413)	0.016	3.175(1.004–10.040)	0.049
T 3/4	134	122		1.918(1.313–2.800)	0.001	2.062(1.372–3.098)	0.001
Pathological N
N0	51	52		1.881(0.859–4.118)	0.114	2.371(1.007–5.583)	0.048
N+	122	116		1.978(1.345–2.909)	0.001	2.063(1.356–3.139)	0.001
Pathological M
M1	12	11		1.976(0.626–6.234)	0.245	12.766(1.719–94.803)	0.013
M0	158	155		1.950(1.356–2.803)	<0.001	2.051(1.390–3.030)	<0.001
TNM stage
Stage I	19	28		1.886(0.496–7.172)	0.352	20.000(0.791–505.604)	0.069
Stage II	59	50		2.258(1.109–4.597)	0.025	2.217(1.079–4.556)	0.030
Stage III	73	74		1.986(1.220–3.232)	0.006	2.025(1.205–3.403)	0.008
Stage IV	18	17		1.987(0.814–4.848)	0.131	3.799(1.064–13.572)	0.040
Radiation therapy
Yes	39	23		4.406(1.709–11.358)	0.002	4.078(1.369–12.147)	0.012
No	125	141		1.725(1.177–2.528)	0.005	2.037(1.352–3.070)	0.001
Targeted therapy
Yes	74	77		3.912(2.160–7.084)	<0.001	3.573(1.903–6.708)	<0.001
No	88	87		1.408(0.894–2.217)	0.140	1.694(1.024–2.804)	0.040
Cancer status
No	120	86		1.641(0.840–3.205)	0.147	1.995(0.967–4.116)	0.062
Yes	45	73		1.681(1.052–2.685)	0.030	1.873(1.144–3.066)	0.013

Notes: ^aAdjusted for age, TNM stage, radiation therapy and targeted molecular therapy; The missing patients of these clinical parameters are the same as Table 1.

Abbreviations: PPP1R3B, protein phosphatase 1 regulatory subunit 3B; HR, hazard ratio; OS, overall survival; GC, gastric cancer.

Table 4 Joint Effects Survival Analysis of Clinical Factors and the PPP1R3B Expression with OS

Group	PPP1R3B	Variables	Events/Total	MST (Months)	Crude HR (95% CI)	Crude P-value	Adjusted HR (95% CI)	Adjusted P-value^a
Histologic grade
A	Low expression	G1 + G2	15/65	70	1		1	1
B	Low expression	G3 + G4	41/108	47	2.069(1.144–3.742)	0.016	1.647(0.798–3.397)	0.177
C	High expression	G1 + G2	35/71	24	3.139(1.706–5.774)	<0.001	3.409(1.639–7.090)	0.001
D	High expression	G3 + G4	49/98	20	3.402(1.894–6.108)	<0.001	3.277(1.610–6.667)	0.001
Radiation therapy
A	Low expression	Yes	7/39	NA	1	1		1
B	Low expression	No	46/125	56	3.429(1.541–7.629)	0.003	3.233(1.236–8.458)	0.017
C	High expression	Yes	12/23	43	4.149(1.630–10.564)	0.003	4.456(1.592–12.473)	0.004
D	High expression	No	70/141	21	5.945(2.693–13.126)	<0.001	6.831(2.724–17.130)	<0.001
Radical resection
I	Low expression	R0	39/144	70	1	1		1
II	Low expression	R1+R2	6/11	16	2.975(1.256–7.048)	0.013	2.879(1.061–7.814)	0.038
III	High expression	R0	61/144	26	2.123(1.410–3.197)	<0.001	2.571(1.641–4.029)	<0.001
IV	High expression	R1+R2	15/17	10	6.355(3.468–11.644)	<0.001	4.379(2.016–9.511)	<0.001
Targeted molecular therapy
I	Low expression	Yes	16/74	70	1	1		1
II	Low expression	No	36/88	47	2.564(1.421–4.627)	0.002	1.859(0.864–4.002)	0.113
III	High expression	Yes	40/77	22	3.605(2.008–6.472)	<0.001	3.381(1.702–6.717)	0.001
IV	High expression	No	42/87	23	3.791(2.115–6.795)	<0.001	3.564(1.669–7.612)	0.001
Stage
E	Low expression	I + II	18/78	73		1		1
F	Low expression	III+IV	37/91	47	1.878(1.068–3.300)	0.029	2.858(1.373–5.950)	0.005
G	High expression	I + II	27/78	35	1.946(1.066–3.553)	0.030	3.047(1.432–6.458)	0.004
H	High expression	III+IV	54/91	18	3.813(2.226–6.531)	<0.001	5.965(2.895–12.290)	<0.001

Note: ^aAdjusted for histologic grade, radiation therapy, radical resection, targeted molecular therapy and stage.

Abbreviations: PPP1R3B, protein phosphatase 1 regulatory subunit 3B; GC, gastric cancer; HR, hazard ratio; MST, median survival time; OS, overall survival; CI, confidence interval.

Table 5 The Prognostic Value of the mRNA Expression of PPP1R3B in Various Clinical Features from KM-Plotter

Group	Low	High	HR (95% CI)	P-value
All	317	314	1.74 (1.4 − 2.17)	5e−07
Histology
Intestinal	134	135	2.51 (1.72 − 3.68)	9.3e−07
Diffuse	120	120	1.28 (0.91 − 1.8)	0.16
Mixed	14	15	0.43 (0.14 − 1.32)	0.13
TNM stage
Stage I	31	31	2.25 (0.67 − 7.51)	0.18
Stage II	69	66	1.85 (0.97 − 3.52)	0.058
Stage III	99	98	1.96 (1.34 − 2.86)	0.00044
Stage IV	70	70	1.33 (0.89 − 1.98)	0.16
Treatment
Surgery	190	190	1.14 (0.86 − 1.52)	0.37
5-FU	17	17	3.94 (1.39 − 11.17)	0.0058
HER2 status
Negative	215	214	1.62 (1.24 − 2.12)	0.00036
Positive	101	101	1.31 (0.9 − 1.91)	0.15
Differentiation
Poorly	60	61	1.27 (0.78 − 2.05)	0.34
Moderately	34	33	0.84 (0.44 − 1.6)	0.59
Well	2	3	NA	0.41

Abbreviations: PPP1R3B, protein phosphatase 1 regulatory subunit 3B; HR, hazard ratio; OS, overall survival; GC, gastric cancer; T, tumour; N, node; M, metastasis.

Figure 4 Joint effects analysis of overall survival stratified by PPP1R3B and STAD clinical parameters.

Notes: Joint effects analysis stratified by PPP1R3B and following clinical parameters: histologic grade (A), radiation therapy (B), radical resection (C), targeted molecular therapy (D), stage (E). Group A, B, a, b, I, II, I, ii, E, F PPP1R3B Low expression. Group C, D, c, d, III, IV, iii, iv, G, H PPP1R3B High expression.

Figure 5 Prognostic value of PPP1R3B (1552670_a_at) expression determined by Kaplan–Meier plotter database.

Notes: Overall survival curves for all patients (A), stage I (B), stage II (C), stage III (D), stage IV (E), HER2 positive (F), HER2 negative (G), 5-Fu treatment (H), surgery treatment(I), intestinal-type (J), diffuse-type (K), mixed-type (L), poor differentiation (M), moderate differentiation (N), well differentiation (O).

Figure 6 GO and KEGG analysis of genes co-expressed with PPP1R3B.

Notes: (A) GO enrichment analysis. (B) KEGG enrichment analysis.

Abbreviations: PPP1R3B, protein phosphatase 1 regulatory subunit 3. GO, Gene Ontology. KEGG, Kyoto Encyclopedia of Genes and Genomes.

Figure 7 GSEA analysis of PPP1R3B in STAD patients using the TCGA database.

Notes: (A–C) GSEA results of C2 reference gene sets for high PPP1R3B expression groups; (D–I) GSEA results of C5 reference gene sets for low PPP1R3B expression groups.

Abbreviations: NES, normalized enrichment score; FDR, false discovery rate; GSEA, gene set enrichment analysis; PPP1R3B, protein phosphatase 1 regulatory subunit 3.