FAM98A promotes proliferation of non-small cell lung cancer cells via the P38-ATF2 signaling pathway

Figures & data

Figure 1 FAM98A expression in NSCLC specimens and cell lines.

Notes: (A) and (B) Protein expression of FAM98A in NSCLC tissues was considerably higher than in noncancerous tissues. *Mean p<0.05. (C) Results showed low FAM98A expression in (a) normal bronchial epithelial cells and (b) normal alveolar epithelial. However, FAM98A was highly expressed in (c) lung squamous cell carcinoma and (d) adenocarcinoma. (D) FAM98A was expressed in different cell lines. (E) FAM98A was localized in the cytoplasm of A549 and SPC cells.

Abbreviations: DAPI, 4′,6-diamidino-2-phenylindole; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; FITC, fluorescein isothiocyanate; NSCLC, non-small cell lung cancer; HBE, human bronchial epithelial.

Table 1 Correlation of FAM98A expression with clinicopathologic features in 131 cases of lung cancer

Factors	N	FAM98A
		Negative	Positive	p-value
Total	131	45	86
Age (years)				0.215
≤60	68	26	42
>60	63	19	44
Gender				0.576
Male	102	35	67
Female	29	10	19
Histological type				0.714
Squamous cell carcinoma	60	18	42
Adenocarcinoma	62	23	39
Others	9	4	5
Differentiation				0.654
Well	15	5	10
Moderate	59	18	41
Poor	57	22	35
TNM stage				0.017
I and II	90	65	25
III	41	20	21
Lymph node metastasis				<0.001
No	73	36	37
Yes	58	9	49

Table 2 The comparison of FAM98A levels in the NSCLC and corresponding adjacent tissues

Group	N	FAM98A		χ^2	p-value
		Negative	Positive
NSCLC	128	20	108	106.61	<0.001a
Adjacent tissues	128	118	10

Note:

a Mean that p<0.05 was statistically significant.

Abbreviation: NSCLC, non-small cell lung cancer.

Figure 2 FAM98A promoted the proliferation of A549 and SPC cells.

Notes: (A) Transfection efficiencies after FAM98A overexpression and depletion by siRNA treatment in A549 and SPC cells were determined by Western blotting. (B) and (C) The proliferation and colony-formation abilities of A549 and SPC cells increased after overexpressing FAM98A and decreased when treated with siRNA targeting FAM98A. The assays were replicated 3 times. *Mean p<0.05; **mean p<0.01.

Abbreviation: NC, negative control.

Figure 3 FAM98A increased cyclin D1 expression and enhanced proliferation via promoting P38-ATF2 phosphorylation.

Notes: (A) The expression of p-P38, p-ATF2, and cyclin D1 were determined after FAM98A overexpression or knockdown in A549 and SPC cells. (B) The expressions of p-P38, p-ATF2, and cyclin D1 were measured after SB203580, a P38 inhibitor, was added to the culture media of A549 and SPC cells with or without FAM98A overexpression. DMSO was used as negative control. (C) The colony formation assay was performed after SB203580, a P38 inhibitor, was added to the culture media of A549 and SPC cells with or without FAM98A overexpression. DMSO was used as negative control. The assays were replicated 3 times.

Abbreviations: DMSO, dimethyl sulfoxide; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; p-ATF2, phosphorylated ATF2; p-P38, phosphorylated P38; NC, negative control.

Figure S1 The protein expressions related to signal pathway and cell cycle after FAM98A overexpression and depletion by siRNA treatment in A549 and SPC cells.

Abbreviations: FAK, focal adhesion kinase; ERK, extracellular signal-regulated kinase; GAPDH, glyceraldehyde-3-phosphate dehydrogenase; JNK, c-Jun N-terminal kinase; NC, negative control.