World J Oncol

World Journal of Oncology, ISSN 1920-4531 print, 1920-454X online, Open Access

Article copyright, the authors; Journal compilation copyright, World J Oncol and Elmer Press Inc

Journal website https://www.wjon.org

Original Article

Volume 13, Number 2, April 2022, pages 84-95

The Diverse Analysis Identifies Mutated KRAS Associated With Radioresistance in Non-Small Cell Lung Cancer

Figure 1. Local tumor progression in a patient with stage III adenocarcinoma lung cancer. (a) Positron emission tomography (PET) image from diagnosis. (b) Intensity-modulated photon radiation therapy plan with isodose lines and planning target volume (PTV) in green colorwash. (c) Post-treatment PET scan shows local tumor progression inside the PTV.

Figure 2. Kaplan-Meier plots of local progression-free survival (LPFS) according to EGFR and KRAS mutation status. (a) LPFS curves for patients with KRAS mutation (red line; krasm = 1), KRAS wild-type (WT; blue line (krasm = 0), P = 0.129). (b) LPFS curves for patients with EGFR mutation (red line; egfr = 1), EGFR WT (blue line; egfr = 0) P = 0.099. EGFR: epidermal growth factor receptor; KRAS: V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog.

Figure 3. (a) Clonogenic assays showed that cell lines with KRAS mutation (H460 and A549) are more resistant than wild-type cells (H1299 and H661) to radiation. (b) H460 (KRAS mutation) and (c) H1299 (KRAS wild-type) treated with 4 Gy X-ray for 1, 8, and 24 h. Cells were then fixed and immune stained for γH2AX foci (red). Nuclei were counterstained with DAPI (blue). (d) For each time point, five to 10 images were captured and used for quantification of γH2AX foci number. The graph represents an average of three independent experiments ± SD. KRAS: V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog; DAPI: 4’,6-diamidino-2-phenylindole; SD: standard deviation.

Figure 4. TCGA LUAD data show differentially expressed genes in the ERK1/2 pathway, phosphatidylinositol I3 kinase (PI3K)/mTOR, p38 MAPK pathway, cell cycle checkpoint signaling, and DNA damage. The repair and EGFR/PKC/AKT pathways presented with differential expression in patients (a) and cell lines (b) with KRAS mutations compared with the wild-type group. Y: patients or cell line with mutation; N: patients or cell line without mutation. TCGA LUAD: The Cancer Genome Atlas for Lung Adenocarcinoma.

**Table 1.** Patient Characteristics
Characteristic	All	Local progression	No local progression	P value
EGFR: epidermal growth factor receptor; KRAS: V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog; WT: wild-type; NSCLC: non-small cell lung cancer.
KRAS status
WT	187	46	141	0.843
Mutation	54	14	40
EGFR status
WT	252	62	190	0.376
Mutation	32	5	27
Age, years, mean ± SD	63.9 ± 10.4	61.9 ± 9.7	64.6 ± 10.6	0.034
Sex
Male	144	38	106	0.296
Female	142	30	112
Race
Other	31	9	22	0.467
White	255	59	196
Karnofsky performance status
> 80	120	26	94	0.476
≤ 80	166	42	124
Disease stage
I - II	34	9	25	0.694
III	252	59	193
Tumor histology
Squamous cell	67	21	46	0.122
Adenocarcinoma	177	35	142
NSCLC, other	42	12	30
Smoking status
No smoking	42	11	31	0.242
Former	178	37	141
Current	61	19	42
Dose, mean ± SD, Gy or Gy (RBE)	68.7 ± 6.2	68.1 ± 5.1	68.7 ± 6.5	0.785
Radiation modality
Photon	173	50	123	0.012
Proton	113	18	95
Chemotherapy
No induction chemotherapy	185	36	149	0.02
Induction chemotherapy	101	32	69
No concurrent chemotherapy	24	8	16	0.251
Concurrent chemo	262	60	202
Gross tumor volume, cm³	122.0 ± 128.1	120.2 ± 120.5	122.5 ± 130.7	0.852

Table 1. Patient Characteristics

Characteristic

All

Local progression

No local progression

P value

EGFR: epidermal growth factor receptor; KRAS: V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog; WT: wild-type; NSCLC: non-small cell lung cancer.

KRAS status

187

141

0.843

Mutation

EGFR status

252

190

0.376

Mutation

Age, years, mean ± SD

63.9 ± 10.4

61.9 ± 9.7

64.6 ± 10.6

0.034

Sex

Male

144

106

0.296

Female

142

112

Race

Other

0.467

White

255

196

Karnofsky performance status

> 80

120

0.476

≤ 80

166

124

Disease stage

I - II

0.694

III

252

193

Tumor histology

Squamous cell

0.122

Adenocarcinoma

177

142

NSCLC, other

Smoking status

No smoking

0.242

Former

178

141

Current

Dose, mean ± SD, Gy or Gy (RBE)

68.7 ± 6.2

68.1 ± 5.1

68.7 ± 6.5

0.785

Radiation modality

Photon

173

123

0.012

Proton

113

Chemotherapy

No induction chemotherapy

185

149

0.02

Induction chemotherapy

101

No concurrent chemotherapy

0.251

Concurrent chemo

262

202

Gross tumor volume, cm³

122.0 ± 128.1

120.2 ± 120.5

122.5 ± 130.7

0.852

**Table 2.** Univariate Analysis of Independent Predictors of Local Progression
	HR	95% CI	P value
EGFR: epidermal growth factor receptor; KRAS: V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog; WT: wild-type; NSCLC: non-small cell lung cancer; HR: hazard ratio; CI: confidence interval.
KRAS status
WT (reference)
Mutation	1.585	0.865 - 2.901	0.135
EGFR status
WT (reference)
Mutation	0.475	0.190 - 1.119	0.113
Age, years	0.986	0.961 - 1.012	0.301
Sex
Male (reference)
Female	0.754	0.462 - 1.229	0.258
Race
Non-white (reference)
White	0.97	0.479 - 1.96	0.933
Karnofsky performance status
> 80 (reference)
≤ 80	1.149	0.698 - 1.891	0.585
Disease stage
I - II (reference)
III	0.966	0.476 - 1.957	0.923
Tumor histology
Squamous cell (reference)
Adenocarcinoma	0.783	0.452 - 1.355	0.382
NSCLC, other	0.78	0.383 - 1.588	0.494
Smoking status
No smoking (reference)
Former	0.886	0.449 - 1.748	0.727
Current	1.217	0.578 - 2.564	0.605
Radiation dose, Gy or Gy (RBE)	1.012	0.969 - 1.057	0.574
Radiation modality
Photon (reference)
Proton	0.772	0.449 - 1.326	0.348
Chemotherapy
No induction chemotherapy (reference)
Induction chemotherapy	1.091	0.673 - 1.768	0.724
No concurrent chemotherapy (reference)
Concurrent chemotherapy	0.385	0.182 - 0.815	0.013
Gross tumor volume, cm³	1.002	0.999 - 1.004	0.058

Table 2. Univariate Analysis of Independent Predictors of Local Progression

95% CI

P value

EGFR: epidermal growth factor receptor; KRAS: V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog; WT: wild-type; NSCLC: non-small cell lung cancer; HR: hazard ratio; CI: confidence interval.

KRAS status

WT (reference)

Mutation

1.585

0.865 - 2.901

0.135

EGFR status

WT (reference)

Mutation

0.475

0.190 - 1.119

0.113

Age, years

0.986

0.961 - 1.012

0.301

Sex

Male (reference)

Female

0.754

0.462 - 1.229

0.258

Race

Non-white (reference)

White

0.97

0.479 - 1.96

0.933

Karnofsky performance status

> 80 (reference)

≤ 80

1.149

0.698 - 1.891

0.585

Disease stage

I - II (reference)

III

0.966

0.476 - 1.957

0.923

Tumor histology

Squamous cell (reference)

Adenocarcinoma

0.783

0.452 - 1.355

0.382

NSCLC, other

0.78

0.383 - 1.588

0.494

Smoking status

No smoking (reference)

Former

0.886

0.449 - 1.748

0.727

Current

1.217

0.578 - 2.564

0.605

Radiation dose, Gy or Gy (RBE)

1.012

0.969 - 1.057

0.574

Radiation modality

Photon (reference)

Proton

0.772

0.449 - 1.326

0.348

Chemotherapy

No induction chemotherapy (reference)

Induction chemotherapy

1.091

0.673 - 1.768

0.724

No concurrent chemotherapy (reference)

Concurrent chemotherapy

0.385

0.182 - 0.815

0.013

Gross tumor volume, cm³

1.002

0.999 - 1.004

0.058

Table 3. Multivariate Analysis of Independent Predictors of Local Progression

KRAS status

EGFR status

HR (95% CI)

P value

HR (95% CI)

P value

EGFR: epidermal growth factor receptor; KRAS: V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog; WT: wild-type; HR: hazard ratio; CI: confidence interval.

KRAS status

WT (reference)

1.961 (1.062 - 3.622)

0.031

Mutation

EGFR status

WT (reference)

0.601 (0.237 - 1.52)

0.283

Mutation

Chemotherapy

No concurrent chemotherapy (reference)

0.301 (0.132 - 0.683)

0.004

0.352 (0.156 - 0.798)

0.012

Concurrent chemotherapy

Gross tumor volume, cm³

1.003 (1.000 - 1.004)

0.013

1.002 (1.000 - 1.005)

0.017