The described invention provides pharmaceutical compositions, systems, and methods directed to the treatment of non-small cell lung cancer (NSCLC) solid tumors comprising tumor cell populations. The method comprises administration of a therapeutic amount of a polypeptide having the amino acid sequence YARAAARQARAKALARQLGVAA (SEQ ID NO: 1) or a functional equivalent thereof, and a pharmaceutical composition comprising a pharmaceutically acceptable carrier, wherein the therapeutic amount of the polypeptide is Inhibition of kinase activity in tumor cell populations and reduction of cancer cell growth, reduction of tumor size, reduction of tumor burden, induction of tumor cell death, overcoming tumor chemoresistance, enhancement of tumor chemosensitivity, Or it is effective for a combination thereof. [Selection] Figure 1記載の発明は、腫瘍細胞集団を含む非小細胞肺癌(NSCLC)固形腫瘍の治療を目的とする医薬組成物、システム、及び方法を提供する。方法は、アミノ酸配列YARAAARQARAKALARQLGVAA(配列識別番号1)を有するポリペプチドまたはその機能的同等形態の治療量、及び医薬的に許容可能な担体を含む医薬組成物の投与を含み、ポリペプチドの治療量は、腫瘍細胞集団におけるキナーゼ活性の阻害、及び癌細胞の増殖低減、腫瘍サイズの低減、腫瘍負荷の低減、腫瘍細胞死の誘導、腫瘍の化学療法抵抗性の克服、腫瘍の化学療法感受性の増進、またはそれらの組み合わせに有効である。【選択図】図1